PHOTO

Kazushi Ishiyama
Section
Research Institute of Electrical Communication
Job title
Professor
Degree
  • 博士(工学)(東北大学)

Professional Memberships 5

  • 機械学会

  • IEEE

  • 金属学会

  • 電気学会

  • 応用磁気学会

Research Areas 2

  • Manufacturing technology (mechanical, electrical/electronic, chemical engineering) / Electronic devices and equipment / micromachine

  • Manufacturing technology (mechanical, electrical/electronic, chemical engineering) / Electric/electronic material engineering / Magnetic Material

Papers 164

  1. Orientation-dependent two-dimensional magnonic crystal modes in an ultralow-damping ferrimagnetic waveguide containing repositioned hexagonal lattices of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" overflow="scroll"><mml:mi>Cu</mml:mi></mml:math> disks

    Kanta Mori, Takumi Koguchi, Toshiaki Watanabe, Yuki Yoshihara, Hibiki Miyashita, Dirk Grundler, Mitsuteru Inoue, Kazushi Ishiyama, Taichi Goto

    Physical Review Applied 21 (1) 2024/01/30

    Publisher: American Physical Society (APS)

    DOI: 10.1103/physrevapplied.21.014061  

    eISSN:2331-7019

  2. Estimation of Material Characteristics of Film-Type Noise Suppressor Using Equivalent Circuit Modeling and Genetic Algorithm Peer-reviewed

    Takahiro Mikami, Sho Muroga, Motoshi Tanaka, Yasushi Endo, Masayuki Naoe, Shuichiro Hashi, Kazushi Ishiyama

    IEEE Transactions on Magnetics 2023/06/26

    DOI: 10.1109/TMAG.2023.3289188  

    ISSN:0018-9464

    eISSN:1941-0069

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    An estimation method of material characteristics of a magnetic film-type noise suppressor on a microstrip line (MSL) was investigated. First, the electrical equivalent circuit of the MSL with a magnetic film was obtained. A resistance due to the ferromagnetic resonance loss was calculated by using the magnetic circuit. A resistance due to the eddy current loss was estimated by the least squares method for regression prediction. Next, the material parameters of the film were estimated by using the genetic algorithm in order to obtain high noise suppression effect at 5, 7, 10 GHz and low insertion loss at 1 GHz. The conductive noise suppression effect by the magnetic film with estimated parameters was calculated by using electromagnetic field simulator. In result, the noise suppression was maximized around each target frequency and low insertion loss at 1 GHz was successfully obtained. The results indicate that the proposed estimation method has the potential for material and geometry design of magnetic noise suppressor in order to obtain required noise suppression effect at the circuit design stage.

  3. Vibration Power Generation Property of U-Shaped Unimorph Device Using Grain-Oriented Electrical Steel Peer-reviewed

    Taku Okada, Shun Fujieda, Shuichiro Hashi, Kazushi Ishiyama, Shigeru Suzuki, Satoshi Seino, Takashi Nakagawa, Takao A. Yamamoto

    MATERIALS TRANSACTIONS 62 (12) 1798-1801 2021/12/01

    Publisher: Japan Institute of Metals

    DOI: 10.2320/matertrans.mt-m2021079  

    ISSN:1345-9678

    eISSN:1347-5320

  4. High-performance vibration power generation using polycrystalline Fe–Co-based alloy due to large inverse magnetostrictive effect Peer-reviewed

    S. Inoue, T. Okada, S. Fujieda, F. Osanai, S. Hashi, K. Ishiyama, S. Suzuki, S. Seino, T. Nakagawa, T. A. Yamamoto

    AIP Advances 11 (3) 035021-035021 2021/03/01

    Publisher: AIP Publishing

    DOI: 10.1063/5.0038903  

    eISSN:2158-3226

  5. Estimation of Noise Suppression in MSL with Co-Zr-Nb Film Considering Impedance Matching

    Takahiro Mikami, Sho Muroga, Motoshi Tanaka, Yasushi Endo, Shuichiro Hashi, Kazushi Ishiyama

    IEEE Transactions on Magnetics 58 (2) 2021

    DOI: 10.1109/TMAG.2021.3087257  

    ISSN:0018-9464

    eISSN:1941-0069

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    An equivalent electrical circuit of a microstrip line (MSL) with a magnetic film was proposed. The estimation method of its circuit parameters was investigated in order to clarify a design guideline for noise suppression sheet (NSS) which was placed on the traces in electronic devices. Firstly, the effect of the complex permeability of the magnetic film on the circuit parameters was investigated by magnetic circuit analysis of the cross section of the line. Secondly, an MSL with a Co-Zr-Nb film was designed as a test bench considering the impedance matching in the signal frequency range (below 1 GHz). Then, its transmission coefficients and the conducted noise suppression was estimated. The result shows that impedance matching was successfully maintained below 1 GHz. The estimated transmission coefficients and the conducted noise suppression almost agreed with the measured ones below the effective FMR frequency of the Co-Zr-Nb film. The results indicate that the proposed equivalent circuit has the potential to estimate circuit parameters and transmission characteristics of the MSL with the magnetic film at the circuit design stage. It is also useful to clarify the design guidelines for NSS placed on the traces in electronic devices.

  6. Magneto-impedance properties of thin-film type sensors using CoNbZr/SiO2 multilayer films Peer-reviewed

    Hiroo Yokoyama, Kosuke Kusunoki, Yoshiaki Hayashi, Shuichiro Hashi, Kazushi Ishiyama

    Journal of Magnetism and Magnetic Materials 478 38-42 2019/01

    DOI: 10.1016/j.jmmm.2019.01.066  

  7. Crosstalk suppression of magnetic films covered by two parallel microstrip lines Peer-reviewed

    Sho Muroga, Jingyan Ma, Yasushi Endo, Shuichiro Hashi, Masayuki Naoe, Motoshi Tanaka, Hiroo Yokoyama, Kazushi Ishiyama

    Japanese Journal of Applied Physics 58 (8) 2019

    DOI: 10.7567/1347-4065/ab2d8d  

    ISSN:0021-4922

    eISSN:1347-4065

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    © 2019 The Japan Society of Applied Physics. This paper demonstrated crosstalk suppressions of three-type noise suppressors using Co-Zr-Nb, Ni-Fe, and (Co-Pd)-CaF2 soft magnetic films. Simple two parallel microstrip lines (MSLs) with the line width of 95 μm were fabricated and used as a test bench to evaluate crosstalk suppression. The films placed on the MSLs suppressed both near- and far-end crosstalks around effective ferromagnetic resonance (FMR) frequencies. By applying an external magnetic field to the films, the FMR contribution to crosstalk suppressions was clarified. These results indicate usefulness of the magnetic films to increase a design freedom of IC chips and packages.

  8. Analysis of Magnetic-Film-Type Noise Suppressor Integrated on Transmission Lines for On-Chip Crosstalk Evaluation

    Jingyan Ma, Sho Muroga, Yasushi Endo, Shuichiro Hashi, Hiroo Yokoyama, Yoshiaki Hayashi, Kazushi Ishiyama

    IEEE Transactions on Magnetics 54 (6) 2018/06

    DOI: 10.1109/TMAG.2018.2812846  

    ISSN:0018-9464

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    © 1965-2012 IEEE. This paper discusses the distribution of magnetic flux density inside a magnetic film covered on a microstrip line for developing a design rule of the magnetic-film-type noise suppressor. The measured and simulation results of the magnetic field distribution and conduction loss agree with each other. The distribution of magnetic flux density B inside the magnetic film can be confirmed numerically through the theoretical calculation of the characteristic length including the complex permeability of the magnetic film. These results demonstrate that the complex permeability of the magnetic film leads to a complex characteristic length and distributed magnetic poles and results in the alternated distribution of B vectors along the distance. These results also suggest that these distributed magnetic poles are required when the inductive crosstalk and conduction loss are considered in the design of patterned magnetic-film-type noise suppressor. Based on these results, this paper could be of great use for the quantitative evaluation of crosstalk between the aggressor and victim lines.

  9. Noise suppression and crosstalk analysis of on-chip magnetic film-type noise suppressor

    Jingyan Ma, Sho Muroga, Yasushi Endo, Shuichiro Hashi, Masayuki Naoe, Hiroo Yokoyama, Yoshiaki Hayashi, Kazushi Ishiyama

    AIP Advances 8 (5) 2018/05/01

    DOI: 10.1063/1.5007315  

    eISSN:2158-3226

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    © 2017 Author(s). This paper discusses near field, conduction and crosstalk noise suppression of magnetic films with uniaxial anisotropy on transmission lines for a film-type noise suppressor in the GHz frequency range. The electromagnetic noise suppressions of magnetic films with different permeability and resistivity were measured and simulated with simple microstrip lines. The experimental and simulated results of Co-Zr-Nb and CoPd-CaF2 films agreed with each other. The results indicate that the higher permeability leads to a better near field shielding, and in the frequency range of 2-7 GHz, a higher conduction noise suppression. It also suggests that the higher resistivity results in a better crosstalk suppression in the frequency range below 2 GHz. These results can support the design guidelines of the magnetic film-type noise suppressor used in the next generation IC chip.

  10. Measurement and Countermeasure Methodologies to Deal with Broadening Unnecessary Radio Wave Invited Peer-reviewed

    Masahiro YAMAGUCHI, Satoshi TANAKA, Shigeyoshi YOSHIDA, Kazushi ISHIYAMA, Makoto NAGATA, Koichi KONDO, Yasuyuki OKIYONEDA, Mitsuharu SATO, Yasunori MIYAZAWA, Kensuke HATAKEYAMA

    IEICE Trans. Commun. J101-B (3) 204-211 2018/03

    DOI: 10.14923/transcomj.2017PEI0001  

  11. Development of Strain and Vibration Sensor using Magnetostriction of Magnetic Thin Film

    久保結人, 枦修一郎, 横井甫, 荒井薫, 石山和志

    電気学会論文誌 E 138 (4) 153‐158(J‐STAGE) 2018

    DOI: 10.1541/ieejsmas.138.153  

    ISSN:1341-8939

  12. Influence of demagnetizing field on thin-film GMI magnetic sensor elements with uniaxial magnetic anisotropy Peer-reviewed

    Kikuchi Hiroaki, Kamata Shingo, Nakai Tomoo, Hashi Shuichiro, Ishiyama Kazushi

    SENSORS AND ACTUATORS A-PHYSICAL 230 142-149 2015/07/01

    DOI: 10.1016/j.sna.2015.04.027  

    ISSN:0924-4247

  13. Electrochemical fabrication of nanocomposite films containing magnetic metal nanoparticles Peer-reviewed

    Y. Hayashi, S. Hashi, H. Kura, T. Yanai, T. Ogawa, K. Ishiyama, M. Nakano, H. Fukunaga

    Japanese Journal of Applied Physics 54 (7) #075201-75201 2015/06

    Publisher: Institute of Physics

    DOI: 10.7567/JJAP.54.075201  

    ISSN:0021-4922

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    Controlling the structure composed of soft and hard magnetic phases at the nanoscale is the key to fabricating nanocomposite magnets with efficient exchange coupling. In our previous study, nanocomposite films containing ferrite nanoparticles were fabricated by a combination of electrophoretic deposition and electroplating to show one possibility of controlling the structure of nanocomposite magnets three-dimensionally by applying self-assembly of magnetic nanoparticles. To expand this combination method to the fabrication of nanocomposite magnets, the use of magnetic metal nanoparticles is desired. In this paper, we attempted to fabricate nanocomposite films composed of Fe–Co nanoparticles in a Fe–Pt matrix by this combination method. Through cross-sectional observation and XRD analysis, a nanostructure composed of Fe–Co nanoparticles embedded in a L1<inf>0</inf>Fe–Pt matrix was confirmed. These results indicate that this method is capable of producing composite materials containing metal magnetic nanoparticles.

  14. 誘導磁気異方性を有する薄膜のAMR特性

    本多 章人, 石山 和志, 枦 修一郎, 横井 甫

    電気関係学会東北支部連合大会講演論文集 2015 139-139 2015

    Publisher: 電気関係学会東北支部連合大会実行委員会

    DOI: 10.11528/tsjc.2015.0_139  

  15. Basic Study of Fabricating High Sensitive Strain Sensor Using Magnetostrictive Thin Film on Si Wafer Peer-reviewed

    Miwa Yasuyuki, Shin Jaewon, Hayashi Yoshiaki, Hashi Shuichiro, Ishiyama Kazushi

    IEEE TRANSACTIONS ON MAGNETICS 51 (1) 2015/01

    DOI: 10.1109/TMAG.2014.2349895  

    ISSN:0018-9464

  16. Enhancement of Sensitivity on Miniaturized Thin-film Magnetoimpedance with Ellipsoidal Element Peer-reviewed

    Kikuchi Hiroaki, Oe Suguru, Uetake Hiroaki, Yabukami Shin, Nakai Tomoo, Hashi Shuichiro, Ishiyama Kazushi

    20TH INTERNATIONAL CONFERENCE ON MAGNETISM, ICM 2015 75 1271-1278 2015

    DOI: 10.1016/j.phpro.2015.12.141  

    ISSN:1875-3892

  17. In Vivo Robot on Magnetic Motion Control

    ISHIYAMA Kazushi

    IEEJ Transactions on Sensors and Micromachines 133 (2) 86-88 2013/02/01

    Publisher: The Institute of Electrical Engineers of Japan

    DOI: 10.1541/ieejjournal.133.86  

    ISSN:1340-5551

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    This article has no abstract.

  18. Measurement for Magnetic-field Distribution Using Pulsed Laser with Magneto-optical Effect Peer-reviewed

    J. Takahashi, S. Hashi, K. Ishiyama

    Journal of the Magnetics Society of Japan Vol. 37 (No. 2) 24-28 2013/01

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/msjmag.1303R004  

    ISSN:1882-2924

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    Electromagnetic interference (EMI) is a serious problem in integrated circuits. The ability to accurately measure low-intensity electromagnetic fields is necessary to overcome this problem. We developed in a previous study a system to make magneto-optical measurements that use short laser pulses and a stroboscopic method to measure magnetic-field waveforms. In this study, we considered the spatial resolution of the system and measured the magnetic field distribution around magnetic heads. The overall results suggest that the system of measurement is capable of measuring EMI if we use a thinner garnet and a higher power laser.

  19. Downsizing of LC Markers for a Wireless Magnetic Position Detection System Peer-reviewed

    S. Hashi, S. Yabukami, K. Ishiyama, K. I. Arai

    Sensor Letters Vol. 11 (No. 1) 98-101 2013/01

    DOI: 10.1166/sl.2013.2789  

  20. Magnetic Properties of Nanostructured Film Composed of Co-Ferrite Nanoparticles and Metal Co Prepared by Combination of Electrophoretic Deposition and Electroplating Peer-reviewed

    Hayashi Yoshiaki, Hashi Shuichiro, Ishiyama Kazushi

    IEEE TRANSACTIONS ON MAGNETICS 48 (11) 3170-3173 2012/11

    DOI: 10.1109/TMAG.2012.2199480  

    ISSN:0018-9464

  21. Wireless Magnetic Sensing System for Bioengineering Application Peer-reviewed

    S. Hashi, K. Ishiyama

    2012 IEEE SENSORS PROCEEDINGS 107-110 2012

    Publisher: IEEE

    ISSN:1930-0395

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    A wireless temperature sensing system for isolated areas such as those in an organism is proposed. The sensor does not need a power supply within it and is only composed of a temperature-sensitive ferrite core, a wound coil and a chip capacitor. Therefore, the sensor is designed as an LC series circuit. The sensor is driven and signals from the sensor are received by using the loop coil with electromagnetic induction. The system can measure the temperature by receiving a field at the resonant frequency corresponding to the temperature of the sensor. As the inductance of the sensor coil changes with the temperature, the resonant frequency is varied. In addition, we proposed magnetic motion-sensing system using same LC resonant sensor. The magnetic signal of the sensor is detected by pick-up coil array. It can be assumed that the flux density from the sensor is a magnetic dipole field. Therefore, the position and orientation of the sensor can be calculated by solving an inverse problem.

  22. Wireless magnetic position sensing system using optimized pick-up coils for high accuracy Peer-reviewed

    S. Hashi, S. Yabukami, H. Kanetaka, K. Ishiyama, K. I. Arai

    IEEE TRANSACTIONS ON MAGNETICS 47 (10) 3542-3545 2011/10

  23. Magnetic Field Waveform Measurement Using Pulsed Laser

    那須野弘, 枦修一郎, 石山和志, 安達信泰

    J Magn Soc Jpn 35 (3) 273-276 (J-STAGE)-276 2011

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/msjmag.10R076zF  

    ISSN:1882-2924

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    Electromagnetic interference(EMI) is a serious problem in integrated circuits, and many studies on EMI measurement have been done. Generally, a metal probe is used to measure the electromagnetic wave, however, the metal probe disarranges the state of the electromagnetic wave. Another problem is that high resolution measurement is required. Because the operating frequency of the integrated circuit is very high, a very high frequency magnetic field measurement is required. To solve these problems, measurement using the magneto-optical effect is suitable. Magneto-optical materials have a smaller effect than that using the metal probe, and the optical measurement is advantageous in the undeformed magnetic field measurement. To achieve high resolution we used a pulsed laser with a short pulse width and propose the stroboscopic method of measurement. The stroboscopic method is advantageous in that it is possible to measure a magnetic field in an arbitrary phase because it synchronizes laser pulses with the magnetic field. In measurements of magnetic field waveforms, it was clarified that the stroboscopic method was effective for measuring magnetic field waveforms and distributions at an arbitrary phase.

  24. Far-Infrared Ferromagnetic Resonance of Magnetic Garnet for High Frequency Electromagnetic Sensor Peer-reviewed

    Nobuyasu Adachi, Daisuke Uematsu, Toshitaka Ota, Masanori Takahashi, Kazushi Ishiyama, Katsumi Kawasaki, Hiroyasu Ota, Kenichi Arai, S. Fujisawa, Susumu Okubo, Hitoshi Ohta

    IEEE TRANSACTIONS ON MAGNETICS 46 (6) 1986-1989 2010/06

    Publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

    DOI: 10.1109/TMAG.2010.2041328  

    ISSN:0018-9464

    eISSN:1941-0069

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    For the sensor probe of high frequency magnetic field in GHz region, (BiLu)(3)Fe5O12 films were prepared by liquid phase epitaxy technique and ferromagnetic resonances were investigated in high frequency region. Magneto-optical ( MO) effect of magnetic garnet was utilized for the imaging sensor of the magnetic field distribution. However, for the application to the characterization of high frequency magnetic field in the GHz frequency region, usual MO measurements are difficult to detect the magnetic filed as the decreasing of the permeability of magnetic garnet. Magnetic resonance is an effective way to induce magnetic moment and enhance the magnetooptical effect in high frequency region of GHz order. In order to understand the possibility of magnetic field sensor of high frequency in detail, far-infrared magnetic resonances were measured at the high frequencies up to 315 GHz in pulsed high magnetic field. Taking account into sensitivity of MO signals and magnetic resonance intensities, magnetooptical method using a garnet film is effective at the frequencies below 100 GHz.

  25. Analysis and improvement of detection accuracy for a wireless motion sensing system using integrated coil component Peer-reviewed

    S. Hashi, S. Yabukami, H. Kanetaka, K. Ishiyama, K. I. Arai

    JOURNAL OF APPLIED PHYSICS 107 (9) 2010/04

  26. Study on the LC marker composed of laminated amorphous ribbon core for a wireless magnetic motion capture system Peer-reviewed

    S. Hashi, S. Yabukami, H. Kanetaka, K. Ishiyama, Y. Okazaki, K. I. Arai

    Journal of Physics: Conference Series 200 92008 2010/02

  27. Study on impedance change of strain sensor using magnetostrictive film

    諏訪靖明, 我妻成人, 枦修一郎, 石山和志

    J Magn Soc Jpn 34 (3) 342-346 (J-STAGE)-346 2010

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/msjmag.1003R010  

    ISSN:1882-2924

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    The strain sensor using inverse magnetostriction effect has very high sensitivity with strain. In oreder to improve the sensitivity, the study on the energy behavior of the strain sensor is very important. Therefore we fabricated the sensor with magnetostrictive film and tried to examine the relationships between magnetoelastic energy and anisotropy energy in this study. In particular, we focused on the magnetic domain change by magnetoelastic energy and Zeeman energy. Moreover, we examined impedance property of the strain sensor applied strain and magnetic property with strain. As a result, using magnetic domain change observation, we could observe the anisotropy energy change by applied magnetoelastic energy and discuss the relationships between magnetoelastic energy and anisotropy energy.

  28. Numerical Study on the Improvement of Detection Accuracy for a Wireless Motion Capture System Peer-reviewed

    S. Hashi, S. Yabukami, H. Kanetaka, K. Ishiyama, K. I. Arai

    IEEE TRANSACTIONS ON MAGNETICS 45 (6) 2736-2739 2009/06

  29. Basic Study of Dispersion of Magnetic Particles with Rotational Magnetic Field

    中村治貴, 枦修一郎, 石山和志

    J Magn Soc Jpn 33 (3) 319-323 (J-STAGE)-323 2009

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/msjmag.0903RG8056  

    ISSN:1882-2924

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    Magnetic particles that are used in the human body need to be dispersed to prevent from blocking the blood flow. In this paper, we propose a new method for the dispersion by using magnetic particles with magnetic anisotropy and applying a rotational magnetic field. To estimate a suitable size for the particles and a rotational frequency to disperse of the particles, theoretical formulas were obtained according to a condition where the state of two magnets changed from aggregated to isolated. We confirmed the condition for the aggregated two magnets to become isolated experimentally by changing the thickness of the coating of the magnet and the frequency of the applied rotational magnetic field. The experimental and theoretical results agreed well. This confirmed that the proposed method could be used to disperse magnetic particles. The size of particles and the rotational frequency for isolation were estimated from these formulas.

  30. Study about a Magnetic Film Structure of a High-Frequency Carrier-Type Magnetic Field Sensor Using Shape Anisotropy

    KATO T., ISHIYAMA K.

    Transactions of the Magnetics Society of Japan 32 (3) 371-375 2008/04/01

    Publisher: The Magnetics Society of Japan (MSJ)

    DOI: 10.3379/msjmag.32.371  

    ISSN:1882-2924

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    We attempted to control the magnetic anisotropy of a high-frequency carrier-type magnetic field sensor by means of shape anisotropy. We examined the size of element necessary to realize low anisotropy strength both experiment ally and theoretically. The theoretical results agreed well with the experimental ones, and we were able to calculate the size of an element with low anisotropy strength theoretically.

  31. Comparison with film substrates of polyimide and Ni for cantilevered magnetic actuators Peer-reviewed

    Chikako Yokota, Kazushi Ishiyama, Ken Ichi Arai

    IEEJ TRANSACTIONS ON ELECTRICAL AND ELECTRONIC ENGINEERING 2 (4) 436-439 2007/07

    Publisher: WILEY

    DOI: 10.1002/tee.20185  

    ISSN:1931-4973

    eISSN:1931-4981

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    This paper describes a cantilevered actuator driven by magnetostriction in a low magnetic field. The dimensions of the two-layer actuator were 1 mm x 5 mm, and amorphous FeSiB was used as the positive magnetostrictive material. The theoretical formulas for the amount of displacement and force of the actuator were obtained. In the experiment, a nonmagnetic polyimide film material and a negative magnetostrictive Ni film material were used as the substrates. The change in the characteristics of the actuator caused by changing the substrate was examined with theoretical formulas and experiments. It is shown that the actuator with Ni as the substrate was designed to obtain the largest displacement and the largest force. (c) 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.

  32. Wireless magnetic motion capture system - Compensatory tracking of positional error caused by mutual inductance Peer-reviewed

    Hashi Shuichiro, Toyoda Masaharu, Yabukami Shin, Ishiyama Kazushi, Okazaki Yasuo, Arai Ken Ichi

    IEEE TRANSACTIONS ON MAGNETICS 43 (6) 2364-2366 2007/06

    DOI: 10.1109/TMAG.2007.892874  

    ISSN:0018-9464

  33. Review of Fabrication and Characterization of Nd-Fe-B Thick Films for Magnetic Micromachines Peer-reviewed

    M. Nakano, S. Sato, F. Yamashita, T. Honda, J. Yamasaki, K. Ishiyama, M. Itakura, J. Fidler, T. Yanai, H. Fukunaga

    IEEE Transactions on Magnetics 43 (6) 2672-2676 2007/06

    Publisher: Institute of Electrical and Electronics Engineers

    DOI: 10.1109/TMAG.2007.893778  

    ISSN:0018-9464

  34. Anisotropy Control of a High-Frequency Carrier-Type Magnetic Field Sensor by Shape Anisotropy

    KATO T., ISHIYAMA K., ARAI K. I.

    Journal of the Magnetics Society of Japan 31 (3) 227-230 2007/05/01

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.31.227  

    ISSN:0285-0192

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    We tried to control the magnetic anisotropy of a high-frequency carrier-type magnetic field sensor by varying the shape of the magnetic film instead of the induced anisotropy. We confirmed that the impedance of the sensor was changed by applying a magnetic field, and showed that the properties of the sensor could be controlled through the design of the magnetic film' s shape.

  35. Magnetic Field Measurement Using a Step-Like GMI Sensor Combined with a Differential Circuit

    NAKAI T., TAKADA K., ABE H., HOSHI N., SUZUKI H., ISHIYAMA K., ARAI K. I.

    Journal of the Magnetics Society of Japan 31 (3) 216-220 2007/05/01

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.31.216  

    ISSN:0285-0192

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    A giant magnetoimpedance sensor with a step-like impedance property was obtained in the case of amorphous Co<sub>85</sub>Nb<sub>12</sub>Zr<sub>3</sub> soft magnetic thin film in a rectangle shape with an in-plane uniaxial easy axis in a direction nearly 60 degrees relative to the width direction of the element. It was shown experimentally that the magnetic field in which the step-like impedance change occurs has an almost constant value with a standard deviation in the microtesra (μT) range. The magnetic field in which the step-like change occurs includes information on the external magnetic field. To realize a magnetic field sensor with an accuracy of nT/Hz<sup>1/2</sup> by using this step-like phenomenon, a differential circuit was studied in combination with an alternating bias field in the kilohertz (kHz) frequency range. The aim of the differential circuit was to make the driving circuit into a digital logic circuit, by using pulse signals timed to coincide with the step-like changes. The alternating bias field increases the sampling number, because of the step-like changes in the bias frequency. The aim of the ac bias is to improve the sensor accuracy by using an averaging effect. This paper reports a first trial of the method. As a result, a high-linearity sensor without hysteresis was obtained, which had a linearity error of less than 0.5% in the range of ±100 μT. A measurement accuracy of 460 nT was achieved with a 20 Hz time constant of the output low pass filter (LPF).

  36. Development of magnetic motion capture system for multi-position detection Peer-reviewed

    Hashi Shuichiro, Toyoda Masaharu, Yabukami Shin, Ohya Masashi, Ishiyama Kazushi, Okazaki Yasuo, Arai Ken Ichi

    SENSOR LETTERS 5 (1) 300-303 2007/03

    DOI: 10.1166/sl.2007.008  

    ISSN:1546-198X

  37. Cantilevered Actuator Driven by Magnetostriction in a Low Magnetic Field

    Yokota C., Yamazaki A., Sendoh M., Agatsuma S., Ishiyama K., Arai K. I.

    Journal of the Magnetics Society of Japan 31 (2) 131-134 2007

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.31.131  

    ISSN:0285-0192

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    This paper describes a cantilevered magnetic actuator driven by magnetostriction in a low magnetic field. The dimensions of the two-layered actuator were 1 mm × 5 mm. Amorphous FeSiB was used as the magnetostrictive material, and polymide film with a thickness of 30 μm was used as the substrate for the experiment. The theoretical formulas for the amount of the displacement and for the force of the actuator were obtained. The calculated values of the displacement and the force were compared with experimental values, and were found to be in close agreement with them. It was also found that the obtained formulas were suitable for the design of the cantilevered actuator.

  38. High-Frequency Carrier-Type Magnetic Field Sensor with a Sub-pT Resolution Using a Magnetic Film and a Transmission Line Peer-reviewed

    Murayama Y., Ozawa T., Yabukami S., Ishiyama K., Arai K.I.

    Journal of the Magnetics Society of Japan 31 (1) 17-22 2007

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.31.17  

    ISSN:0285-0192

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    We developed a very sensitive high-frequency carrier-type magnetic field sensor with a sub-pT resolution using a resonating transmission line. Meander-type sensor elements using amorphous CoNbZr films were fabricated. We obtained a magnetic field resolution of 7.4 x 10<sup>-13</sup> T/Hz<sup>1/2</sup> at 501 kHz. The detectable magnetic field was limited bythe noise caused by nonlinear magnetic excitation. We analyzed the quality factor of the resonance for enhancementof the signal-to-noise ratio.

  39. Wireless magnetic motion capture system for multi-marker detection Peer-reviewed

    Shuichiro Hashi, Masaharu Toyoda, Shin Yabukami, Kazushi Ishiyama, Yasuo Okazaki, Ken Ichi Arai

    IEEE TRANSACTIONS ON MAGNETICS 42 (10) 3279-3281 2006/10

    Publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

    DOI: 10.1109/TMAG.2006.880737  

    ISSN:0018-9464

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    A wireless multi-motion capture system using five LC resonant magnetic markers has been developed and is demonstrated. Each marker has an individual resonant frequency, 157, 201, 273, 323, and 440 kHz, respectively. A new measuring technique is applied in order to reduce the acquisition time. In this new technique the markers are excited by a superposed wave corresponding to the all resonant frequencies while the voltage signals induced through pick-up coils are separated in a frequency spectrum by FFT analysis. Regardless of the number of markers, the voltage amplitude for each resonant frequency can be easily obtained simultaneously and thus the proposed system can detect multiple markers. The positional accuracy for five markers is less than 2 mm within 100 mm of the pick-up coil array.

  40. Magnetic motion capture system using LC resonant magnetic marker composed of Ni-Zn ferrite core Peer-reviewed

    S. Hashi, S. Yabukami, M. Toyoda, M. Ohya, K. Ishiyama, Y. Okazaki, K. I. Arai

    JOURNAL OF APPLIED PHYSICS 99 (8) 08B312 2006/04

  41. Chaotic noise increase in high-frequency carrier-type thin-film sensor Peer-reviewed

    S. Yabukami, Y. Murayama, K. Ishiyama, K. Arai, H. Okuno

    INTERMAG 2006 - IEEE International Magnetics Conference 689 2006

    DOI: 10.1109/INTMAG.2006.376413  

  42. Development of wireless magnetic motion capture system for multi-marker detection Peer-reviewed

    S. Hashi, M. Toyoda, S. Yabukami, K. Ishiyama, Y. Okazaki, K. Arai

    INTERMAG 2006 - IEEE International Magnetics Conference 524 2006

    DOI: 10.1109/INTMAG.2006.376248  

  43. Highly accurate position sensing system for a slim LC resonated marker using phase information Peer-reviewed

    S. Yabukami, T. Kato, S. Hashi, K. Ishiyama, K. Arai, Y. Okazaki

    INTERMAG 2006 - IEEE International Magnetics Conference 527 2006

    DOI: 10.1109/INTMAG.2006.376251  

  44. High-Sensitivity AC Magnetic Field Measurement Based on the Reflection Signal of a High-Frequency Carrier-Type Magnetic Field Sensor Peer-reviewed

    NAKAI T., SENDOH M., YABUKAMI S., ISHIYAMA K., ARAI K. I.

    Journal of the Magnetics Society of Japan 30 (6) 550-554 2006

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.30.550  

    ISSN:0285-0192

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    The high-frequency carrier-type (HFC-type) magnetic field sensor realizes very high sensitivity without any cooling apparatus for the sensor element. An important technique for obtaining high sensitivity is the use of a high-frequency current applied to the sensor element. The maximum sensitivity is obtained at frequencies up to the ferromagnetic resonance of the sensor magnetic thin film; for example, hundreds of megahertz for amorphous CoNbZr films. It is becoming important to study high-frequency circuits for driving HFC-type magnetic field sensors in order to achieve any practical applications such as nondestructive testing or biomedical applications. In this paper, a method of reflection signal measurement is studied in order to measure alternating magnetic fields with very small magnitude. A theoretical formula based on an equivalent circuit model was obtained for the relation between the sensor property and measurement sensitivity. An experimental confirmation was carried out by comparing this formula with experimental results. Finally, the measurement of a small alternating magnetic fields was effected by combining reflection signal measurement with the carrier-suppressing method.

  45. 熱処理温度制御による高周波キャリア型薄膜磁界センサの高感度化 Peer-reviewed

    村山芳隆, 小澤哲也, 堀越直, 薮上信, 石山和志, 荒井賢一

    日本応用磁気学会 30 (2) 237-242 2006

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.30.237  

    ISSN:0285-0192

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    通研インポート200703

  46. スパイラル型磁気マイクロマシンを用いたディスポーザブルポンプシステム Peer-reviewed

    日本応用磁気学会

    久富伸一、山崎彩、石山和志、我妻成人、仙道雅彦、荒井賢一 30 (2) 306-310 2006

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.30.306  

    ISSN:0285-0192

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    通研インポート200703

  47. 磁性薄膜を用いた片持ち梁型磁気アクチュエータに関する検討 Peer-reviewed

    横田周子, 山崎彩, 仙道雅彦, 我妻成人, 師岡ケイ子, 石山和志, 荒井賢一

    日本応用磁気学会 30 (2) 302-305 2006

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.30.302  

    ISSN:0285-0192

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    通研インポート200703

  48. 3次元泳動特性解析法を用いたらせん型磁気マイクロマシンの形状設計 Peer-reviewed

    山崎彩, 仙道雅彦, 石山和志, 早瀬敏幸, 荒井賢一

    日本機械学会論文集C 72 (723) 3555-3560 2006

    Publisher: The Japan Society of Mechanical Engineers

    DOI: 10.1299/kikaic.72.3555  

    ISSN:0387-5024

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    通研インポート200703

  49. 磁気トルクを利用したマイクロマシンの小型化に関する検討 Peer-reviewed

    山崎彩, 仙道雅彦, 石山和志, 荒井賢一

    電気学会論文誌E 126 (11) 590-595 2006

    DOI: 10.1541/ieejsmas.126.590  

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    通研インポート200703

  50. 泳動型マイクロマシンの推力に関する研究 Peer-reviewed

    菊地健司, 山崎彩, 仙道雅彦, 石山和志, 荒井賢一

    日本応用磁気学会 30 (2) 294-297 2006

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.30.294  

    ISSN:0285-0192

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    通研インポート200703

  51. 複数LC共振型磁気マーカを用いた多点位置検出システム Peer-reviewed

    豊田征治, 枦修一郎, 薮上信, 大矢雅志, 石山和志, 岡崎靖雄, 荒井賢一

    日本応用磁気学会 30 (3) 391-395 2006

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.30.391  

    ISSN:0285-0192

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    通研インポート200703

  52. 端部磁性体を配置した高周波キャリア型磁界センサの感度向上に関する研究 Peer-reviewed

    仙道雅彦, 中居倫夫, 橘奈緒子, 星則光, 鈴木秀夫, 堀越直, 薮上信, 石山和志, 荒井賢一

    日本応用磁気学会 30 (2) 225-228 2006

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.30.225  

    ISSN:0285-0192

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    通研インポート200703

  53. Wireless magnetic micromachine of planar structure with magnetic thin film Peer-reviewed

    A Yamazaki, M Sendoh, K Ishiyama, KI Arai

    IEEE TRANSACTIONS ON MAGNETICS 41 (10) 4021-4023 2005/10

    Publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

    DOI: 10.1109/TMAG.2005.855156  

    ISSN:0018-9464

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    Magnetic micromachines are driven by a magnetic field. They require no power supply cables, no batteries, and no controlling systems on the body of the machine. The magnetic micromachine of planar structure was fabricated with magnetic thin film. The size of this micromachine is 30 x 60 x 12 mu m. The micromachine swam at the rotational frequency of 1-10 Hz in the water with a kinematic viscosity of 1 mm(2)/s and a Reynolds number of 0.1-1. The magnetic torque required for rotating the micromachine was very small, and it was clarified that the value could be realized with a magnetic thin film.

  54. Fabrication of a spiral type magnetic micromachine for trailing a wire Peer-reviewed

    K Kikuchi, A Yamazaki, M Sendoh, K Ishiyama, KI Arai

    IEEE TRANSACTIONS ON MAGNETICS 41 (10) 4012-4014 2005/10

    Publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

    DOI: 10.1109/TMAG.2005.855155  

    ISSN:0018-9464

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    A magnetic micromachine capable of trailing a wire was fabricated. The micromachine was constructed of a permanent magnet, a copper tube, and a spiral shape made of a tungsten wire. The magnet was magnetized to the diametrical direction. When a rotational magnetic field was applied, the machine rotated and moved in a silicone oil. It was experimentally found that the blade angle of the machine that produced the largest thrust force was 45 degrees. The micromachine was able to trail a wire in a narrow waterway simulating a blood vessel. These results show that the magnetic micromachine has great potential for navigating medical catheters.

  55. Development of Real-time and Highly Accurate Wireless Motion Capture System Utilizing Soft Magnetic Core Peer-reviewed

    S. Hashi, Y. Tokunaga, S. Yabukami, M. Toyoda, K. Ishiyama, Y. Okazaki, K. I. Arai

    IEEE TRANSACTIONS ON MAGNETICS 41 (10) 4191-4193 2005/10

  56. Direction Control of a Magnetic Micromachine Capable of Moving in a Liver

    SOMA M., SENDOH M., ISHIYAMA K., SHOJI K., ATANABE H., ARAI K. I.

    Journal of the Magnetics Society of Japan 29 (5) 594-597 2005/05/01

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.29.594  

    ISSN:0285-0192

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    A magnetic micromachine for driving in a liver was fabricated. It consisted of a cylindrical permanent magnet, a cutting tip at the end of the magnet, and a spiral structure around the magnet. The magnet was magnetized in the direction of its diameter. When a rotating magnetic field was applied, the magnet was rotated by the magnetic torque, and the spiral structure produced a thrust force perpendicular to the rotation plane of the field. The micromachine was able to penetrate the liver of a swine and a bovine to a depth of 40-45 mm in 20-40 seconds. In addition, it was demonstrated that the driving direction of the micromachine could be controlled by changing the direction of the rotating magnetic field. The radius of a turn was 25 mm. These results show that the micromachine has great potential for medical applications such as local hyperthermia.

  57. Moving of a Magnetic Actuator for a Capsule Endoscope in the Intestine of a Pig

    CHIBA A., SENDOH M., ISHIYAMA K., ARAI K. I.

    Journal of the Magnetics Society of Japan 29 (3) 343-346 2005/03/01

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.29.343  

    ISSN:0285-0192

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    Application of a magnetic actuator to a capsule endoscope is proposed. Capsule-type magnetic actuators were fabricated and their motion properties were investigated in a silicone tube and in the intestine of a pig. The dummy capsule is 11 mm in diameter and 40 mm in length. This magnetic actuator is composed of a permanent magnet inside the dummy capsule and spiral structures outside it. The permanent magnet is magnetized in the direction of the diameter. When a rotational magnetic field is applied, the magnetic actuator rotates and moves wirelessly. The velocity of capsules with top spirals was examined in a silicone tube. In addition, a motion test was conducted in the intestine of a pig. The actuator can pass through the small and the large intestines over distances of 450 mm and 400 mm, respectively, in less than 150 s. The capsule can pass out of the bag-shaped section of the large intestine. This result shows that the actuator has the potential to be used in the guidance system of a capsule endoscope.

  58. Fabrication of a Magnetic Micromachine Trailing a Wire

    KIKUCHI K., YAMAZAKI A., SENDOH M., ISHIYAMA K., ARAI K. I.

    Journal of the Magnetics Society of Japan 29 (2) 176-179 2005/02/01

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.29.176  

    ISSN:0285-0192

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    A magnetic micromachine capable of trailing a wire was fabricated. The micromachine was constructed of a permanent magnet, a copper tube, and a spiral shape made from a tungsten wire. The magnet was magnetized in the direction of its diameter. When a rotational magnetic field was applied, the machine rotated and moved in silicone oil. Experiments showed that a spiral shape produced the largest thrust force. The micromachine was able to trail a wire in a small waterway created to simulate a blood vessel. These results show that the micromachine has great potential for navigating medical catheters.

  59. Fabrication of Magnetic Micro-Machine of Planar Structure

    YAMAZAKI A., SENDOH M., ISHIYAMA K., MOROOKA K., ARAI K. I.

    Journal of the Magnetics Society of Japan 29 (2) 157-160 2005/02/01

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.29.157  

    ISSN:0285-0192

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    Magnetic micro-machines are driven by a magnetic field. They require no power-supply cables, no batteries, and no control systems on the body of the machine. We fabricated a magnetic micro-machine with a planar structure. In the experiment, the micro-machine swam at a speed of 0.1 to 3 mm/s and had Reynolds numbers between 10<sup>-3</sup> and 1. This result indicates that the shape of this micro-machine is suitable for miniature swimming machines.

  60. Micropump with a Spiral-Type Magnetic Micromachine

    HISATOMI S., YAMAZAKI A., SENDOH M., ISHIYAMA K., ARAI K. I.

    Journal of the Magnetics Society of Japan 29 (2) 161-164 2005/02/01

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.29.161  

    ISSN:0285-0192

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    A micropump with a spiral-type magnetic micromachine was fabricated. The magnetic micromachine was composed of a permanent magnet and a spiral coil. When a rotating magnetic field was applied, the machine rotated and produced a thrust force in a liquid. However, the machine remained still and pumped the liquid at the point of equilibrium between the thrust force and a force created by the field gradient. We experimentally examined the basic properties of the pump, such as the flow rate and pressure. As a result, we found that the latter two properties can be controlled by adjusting the frequency of the rotating magnetic field. The pump was able to produce a maximum pressure of 116 Pa and a flow rate of several ml/min.

  61. 345 Design of Spiral Magnetic Micro-machine with Three-Dimensional Analysis of Swimming Properties

    Yamazaki A., Sendoh M., Ishiyama K., Hayase T., Arai K. I.

    Proceedings of the JSME Bioengineering Conference and Seminar 2004 337-338 2005

    Publisher: The Japan Society of Mechanical Engineers

    DOI: 10.1299/jsmebs.2004.17.0_337  

  62. Design of a High-Frequency-Carrier-Type Thin-Film Magnetic Field Sensor Peer-reviewed

    HORIKOSHI N., YABUKAMI S., MURAYAMA Y., OZAWA T., ISHIYAMA K., ARAI K. I.

    Journal of the Magnetics Society of Japan 29 (4) 472-476 2005

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.29.472  

    ISSN:0285-0192

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    We designed high-frequency-carrier-type thin-film sensors to obtain high sensitivity. We consider the relation between the sensor form and the sensor to be characteristic. When the sensor area was fixed to 5 mm × 5 mm, and the sensor interval was 30 μm, the width of the sensor with the best sensitivity was set to 200-400 μm. We fabricated a meander-type sensor element, and compared the calculated and measured result. It was found that-they mostly in agreed.

  63. Development of an Enhanced-Phase-Detection-Type Magnetic Field Sensor using a High-Frequency-Carrier Peer-reviewed

    Ozawa T., Yokota C., Horikoshi N., Yabukami S., Ishiyama K., Arai K. I.

    Journal of the Magnetics Society of Japan 29 (6) 663-666 2005

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.29.663  

    ISSN:0285-0192

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    The impedance of a magnetic thin film changes when a magnetic field is applied. The high-frequency-carrier magnetic field sensor, also called a GMI sensor, employs this phenomenon as its principle. We directed our attention to the change in the phase characteristic, and measured the magnetic field by measuring the phase of the high-frequency-carrier magnetic field sensor as a phase difference. Although the high-frequency-carrier magnetic field sensor is optimized for impedance detection, it is not appropriate for measuring the magnetic field by detecting the phase difference. To improve its resolution and sensitivity in this respect, we developed an enhanced-phase-difference-detection-type magnetic field sensor. As a result, we obtained a best rate of change of 63.5 degree/Oe and a resolution of 2.6 × 10<sup>-7</sup> Oe/Hz<sup>1/2</sup>.

  64. Development of an AC Magnetic Field Measurement System Using Phase Difference Detection of a High-Frequency-Carrier Magnetic Field Sensor Peer-reviewed

    Ozawa T., Mawatari H., Yabukami S., Ishiyama K., Arai K. I.

    Journal of the Magnetics Society of Japan 29 (8) 831-837 2005

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.29.831  

    ISSN:0285-0192

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    The impedance and phase characteristic of a magnetic thin film changes when a magnetic field is applied. The high-frequency-carrier magnetic field sensor, also called a GMI sensor, employs this phenomenon as its principle. We directed our attention to the change in the phase characteristic, and measured the dc magnetic field by measuring the phase as a phase difference, using the dual-mixer time-difference method. We optimized the method and the continuous sampling condition to measure the phase difference, and developed an efficient system for measuring the continuous sampling phase difference with low noise. The system was successfully used to measure the ac magnetic field by continuous sampling of the phase difference of a high-frequency-carrier magnetic field sensor.

  65. Wireless motion capture system using magnetically coupled LC resonant marker Peer-reviewed

    S. Hashi, Y. Tokunaga, S. Yabukami, T, Kohno, T. Ozawa, Y. Okazaki, K. Ishiyama, K. I. Arai

    Journal of Magnetism and Magnetic Materials 290-291 1330-1333 2005/01

  66. Wireless micro swimming machine with magnetic thin film

    Aya Yamazaki, Masahiko Sendoh, Kazushi Ishiyama, Ken Ichi Arai, Ryutaro Kato, Masaki Nakano, Hirotoshi Fukunaga

    Journal of Magnetism and Magnetic Materials 272-276 (1) 1741-1742 2004/05/01

    DOI: 10.1016/j.jmmm.2003.12.337  

    ISSN:0304-8853

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    As the magnetic micro-machines are driven by a magnetic field, they require no power supply cables, no batteries, and no controlling systems on the machine body. We fabricated the spiral-type micro-machine (outer diameter; 0.14 mm, length; 1.0 mm) by a tungsten wire (φ 20 μm). NdFeB film magnet was deposited on the spiral-machine by the PLD method. In the experiment, the wireless micro-machine swam at the speed of 0.2-1.6mm/s. This result indicated that the spiral shape was suitable for miniature swimming machine. © 2003 Elsevier B.V. All rights reserved.

  67. Magnetic Biased HFC-Type Magnetic Field Sensor with a Coplanar Thin-Film Magnet

    Nakai T., Yamaguchi M., Ishiyama K., Arai K.I.

    Journal of the Magnetics Society of Japan 28 (2) 132-135 2004

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.28.132  

    ISSN:0285-0192

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    A high-frequency carrier-type (HFC-type) thin-film magnetic field sensor (or giant magneto-impedance, GMI, sensor) needs a bias magnetic field of Oe order for magnetic field measurement. In this report, a thin-film magnetic bias with coplanar layout is proposed for dc bias supply. The merits of the coplanar thin-film magnetic bias are as follows. Magnetic property degradation caused by both lamination of magnetic thin-films and heat treatment is avoided. The heat treatment is indispensable for realizing uniaxial anisotropy in a Co<sub>85</sub>Nb<sub>12</sub>Zr<sub>3</sub> amorphous sensor element. Since a thin-film fabrication process is suitable for creating a coplanar pattern with precise dimensions, a precise dc bias field is obtained. An additional new structure proposed in this report uses a low-resistivity thin-film magnet for the current path of the sensor element. An SmCo<sub>5</sub> amorphous thin-film magnet was proposed for this structure. This conductive metal bias magnet with coplanar layout is suitable for both the return path of the carrier current, which simplifies the sensor structure, and the impedance-matching ground plane for high-frequency carriers. We confirmed the properties of these proposed structures by experiment. The temperature property and 85°C 85% RH treatment property of the sensor were also measured. The results show the effectiveness of coplanar magnetic bias in an SmCo<sub>5</sub> amorphous thin-film magnet.

  68. Three-dimensional analysis of swimming properties of a spiral-type magnetic micro-machine Peer-reviewed

    Aya Yamazaki, Masahiko Sendo, Kazushi Ishiyama, Toshiyuki Hayase, Kenichi Arai

    Sensors and Actuators A、105 103-108 2003/06

    DOI: 10.1016/S0924-4247(03)00069-4  

  69. Effective Area of Hyperthermia Using Implanted Heaters Peer-reviewed

    清水潤一, 佐藤文博, 松木英敏, 佐藤忠邦, 仙道雅彦, 石山和志, 荒井賢一

    日本応用磁気学会誌 27 (4) 456-459 2003/04/01

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.27.456  

    ISSN:0285-0192

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    Hyperthermia is a well-known treatment for cancer. When the tumor volume is somewhat large, a temperature difference occurs between the tumor core and the near edge. High-temperature hyperthermia is proposed to keep the temperature of the heaters high. The soft-heating method used excites a thermosensitive magnetic heater in a high-frequency magnetic field. The temperature distribution when two or more heaters were used was measured for a hybrid heater composed of thermosensitive magnetic material and a metal ring, and the effective area for hyperthermia was examined.

  70. Fabrication of Magnetic Micromachine for Local Hyperthermia Peer-reviewed

    Masahiko Sendo, Kazushi Ishiyama, Ken Ichi Arai, Masayuki Jojo, Fumihiro Sato, Hidetoshi Matsuki

    IEEE TRANSACTIONS ON MAGNETICS 38 (5) 3359-3361 2002/09/01

    DOI: 10.1109/TMAG.2002.802305  

  71. Nanostructured metallic cores with extremely low loss and controlled permeability Peer-reviewed

    H Fukunaga, T Yanai, H Tanaka, M Nakano, K Takahashi, Y Yoshizawa, K Ishiyama, KI Arai

    IEEE TRANSACTIONS ON MAGNETICS 38 (5) 3138-3140 2002/09

    Publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

    DOI: 10.1109/TMAG.2002.802421  

    ISSN:0018-9464

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    Magnetic anisotropy perpendicular to the ribbon axis was induced in nanocrystalline FeCuNbSiB ribbons by crystallization under tensile stress, and the relative permeability of the ribbon was approximately 250. Toroidal cores for a choke coil were prepared from the ribbons. The magnetic loss decreased with increasing the core diameter and it was found that deterioration of magnetic properties due to formation of a toroidal core was suppressed by making the core diameter larger than the critical diameter determined from the values of magnetostriction and induced anisotropy. As a result, toroidal cores with extremely low loss were achieved. The permeability of the cores developed was kept constant up to 1 MHz and their magnetic loss was much smaller than the loss values reported previously for nanostructured and amorphous cores with low permeability. The measured magnetic loss agreed with the calculated classical eddy current loss. In addition, the permeability and magnetic loss were kept constant up to the dc bias field, being three times higher than that applicable to a ferrite cut core with the same permeability value.

  72. Effect of Cu precipitation from metastable crystalline BCC-Fe(Cu) films on magnetic properties Peer-reviewed

    XF Bi, SK Gong, HB Xu, K Ishiyama, K Arai

    JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS 241 (2-3) 157-161 2002/03

    Publisher: ELSEVIER SCIENCE BV

    DOI: 10.1016/S0304-8853(02)00030-6  

    ISSN:0304-8853

    eISSN:1873-4766

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    Fe-Cu films with various contents of Cu were prepared by using the RF sputtering method. followed by an annealing treatment in vacuum at different temperatures for 2 min. X-ray diffraction analysis was made to identify the structural change of the films after annealing. It A as found that, when the Cu content was no more than 50 at, G, the coercivity decreased after annealing at 523 K, owing to the reduction of internal stress induced during the sputtering process, The coercivity, however, increased after annealing at 773 K, caused by the precipitation of Cu from the metastable BCC-Fe(Cu) solid solution. Furthermore, the increase of Cu content in the BCC-Fe decreased the temperatures at which the coercivity began to increase. The effects of increased annealing temperatures caused a decrease in lattice parameter of BCC-Fe accompanied by a slight decrease in saturation magnetization, M-s for all Cu concentrations. (C) 2002 Elsevier Science B.V. All rights reserved.

  73. Nanostructured cores with extremely low loss and controlled permeability Peer-reviewed

    Hirotoshi Fukunaga, H. Tanaka, Takeshi Yanai, Masaki Nakano, Ken Takahashi, Yoshihito Yoshizawa, Kazushi Ishiyama, Ken Ichi Arai

    Digests of the Intermag Conference 2002

    ISSN:0074-6843

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    The nanostructured cores with extremely low loss and controlled permeability were discussed. The deterioration of magnetic properties due to formation of a toroidal core was suppressed by controlling the core diameter and/or magnetostriction. It was found that the superior magnetic properties were due to the large saturation magnetization and magnetization process due to rotation of magnetization as well as the nanostructure of the cores.

  74. Trial Production and Evaluation of Guide-wire Bending by MagneticTorque Peer-reviewed

    Kazushi Ishiyama, Ken Ichi Arai

    Trans.IEE of Japan 122-A (3) 343-347 2002

  75. Fabrication of Magnetic Micro-Machine with Heating Device Peer-reviewed

    M.Sendoh, K.Ishiyama, K.I.Arai, M.Jojo, F.Sato, H.Matsuki

    J.Mag.Soc.Jpn 26 (4) 629-632 2002

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.26.629  

    ISSN:0285-0192

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    A magnetic micro-machine with a heating device, which can run in gel, was fabricated. The machine is composed of a screw tip, a rod-shaped NdFeB magnet, and a rod-shaped permalloy unit. The machine is 2 mm in diameter and 19 mm in length. The NdFeB magnet is magnetized to the direction of the diameter. When a rotational magnetic field with rotation frequency of 10 Hz is applied, the machine rotates and moves in agar. In addition, a machine placed in an alternating magnetic field, at 100kHz, produces heat by iron loss. It was demonstrated that the machine can move 20 mm and be heated above 50°C. This means a wireless heating mechanism could be obtained using an alternating magnetic field and a rotational magnetic field. This machine has the great possibilities for local medical operations for cancer.

  76. Analysis of Swimming Properties of Magnetic Micro-machine of 0.5mm in Diameter Peer-reviewed

    A.Yamazaki, M.Sendoh, K.Ishiyama, T.Hayase, K.I.Arai

    J.Mag.Soc.Jpn 26 (4) 645-648 2002

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.26.645  

    ISSN:0285-0192

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    The swimming properties of miniature magnetic micro-machines with spiral structures were analyzed theoretically employing a two-dimensional finite volume method. Based on the analysis results, a miniature machine was fabricated. The miniature machine was found to be able to swim in a fluid with Reynolds numbers of 10<sup>-5</sup> to 0.2. This result shows that the machine is suitable as a micro-size swimming machine. Good agreement was obtained between experimental and theoretical results. This method made it possible to design an optimum machine structure.

  77. Fabrication and Individual Control of Magnetic Micro-machine Moving in a Gel Peer-reviewed

    M.Sendoh, K.Ishiyama, K.I.Arai

    J.Mag.Soc.Jpn 26 (4) 649-652 2002

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.26.649  

    ISSN:0285-0192

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    Magnetic micro-machines capable of boring into gel were fabricated. The micro-machines are composed of rod-shape NdFeB magnets and screw-shaped tips. The magnet is magnetized in the direction of the diameter. The diameters of all machines are 0.8 mm. A medical injector can insert this size machine. When a rotational magnetic field is applied, the machine rotates and moves in agar. When the frequency of the external rotational field exceeds the step-out frequency, the machine cannot synchronize to the field and thus stops. The velocity varies greatly with changes in the machine shape. A test using two machines that have different velocities and step-out frequencies, we demonstrated that multiple machines can work individually.

  78. Starting Characteristics of Spiral-Type Magnetic Micro-Machine Peer-reviewed

    M.Sendoh, K.Ishiyama, M.Yamaguchi, K.I.Arai

    J.Mag.Soc.Jpn 26 (4) 653-656 2002

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.26.653  

    ISSN:0285-0192

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    Magnetic micro-machines composed of cylindrical bodies with magnets and spiral blades, can be made to swim in liquid when a rotational magnetic field is applied. In this study, starting characteristics of a micro-machine were examined theoretically and experimentally. The starting characteristics depended on the kinematic viscosity of the liquid and the machine's moment of inertia. We demonstrated that the micro-machine could start in a liquid having a kinematic viscosity of 5 mm<sup>2</sup>/s despite sudden application of an external rotational field of 125 Hz, because the machine's moment of inertia was very small.

  79. Magnetic micromachines for medical applications Peer-reviewed

    K. Ishiyama, M. Sendoh, K. I. Arai

    Journal of Magnetism and Magnetic Materials 242-245 1163-1165 2002

    DOI: 10.1016/S0304-8853(01)01181-7  

  80. Smart actuator with magneto-elastic strain Peer-reviewed

    K. Ishiyama, K. Imamura, K. I. Arai

    Journal of Magnetism and Magnetic Materials 242-245 41-46 2002

    DOI: 10.1016/S0304-8853(01)01293-8  

  81. Swimming micro-machine driven by magnetic torque Peer-reviewed

    K Ishiyama, M Sendoh, A Yamazaki, KI Arai

    SENSORS AND ACTUATORS A-PHYSICAL 91 (1-2) 141-144 2001/06

    Publisher: ELSEVIER SCIENCE SA

    DOI: 10.1016/S0924-4247(01)00517-9  

    ISSN:0924-4247

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    Magnetic micro-machines capable of swimming through liquid or gel were fabricated. The micro-machines were driven by an external rotating magnetic field and featured a screw-shaped structure and permanent magnet. The machines could swim under condition of a Reynolds number (Re) of 10(-7) and were able to run through agar or a bovine tissue sample using the same principle. Their running behavior was dependent on the frequency and strength of the external field, and on the surrounding media. These machines have great potential for medical applications in the human body. (C) 2001 Elsevier Science B.V. All rights reserved.

  82. 柔軟基板上に形成した磁気弾性歪みセンサ Peer-reviewed

    ISHIYAMA Kazushi

    日本応用磁気学会誌 25 (4) 983-986 2001

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.25.983  

    ISSN:0285-0192

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    Micro-strain sensors using the magnetostrictive properties of FeCeSiB films were investigated. To avoid the effects of the rigidity of the substrate on the stress sensitivity, a sensor was formed on thin polyimide ribbons (50 μm thick), which have superior heat resistance, wide elastic region, and excellent flexibility. By using the large difference in the coefficient of thermal expansion between FeCoSiB and polyimide, the residual stress in the magnetostrictive FeCoSiB patterned film was controlled. The sensor was formed under optimized conditions, and had an extremely high value of the figure of merit F = (ΔZ/Z)/Δε (change in film impedance Z per unit ε) of about 1500 at a carrier current frequency of 700 MHz. In addition, the point of stress representing the largest sensitivity of the sensor was controlled by controlling the field annealing conditions.

  83. 磁気を利用したワイヤレス温度計測 Peer-reviewed

    ISHIYAMA Kazushi

    日本応用磁気学会誌 25 (4) 1043-1046 2001

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.25.1043  

    ISSN:0285-0192

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    A wireless temperature sensing system for isolated local areas such as those in an organism was investigated. The sensor does not need an internal power supply, and is composed only of a ferrite rod (1x1x10 mm) with low Curie temperature, a chip capacitor, and a wound coil. It was therefore possible to reduce the volume of the sensor to less than that of a medicine capsule, and the sensor is designed as an LC series circuit. As the inductance of the coil changes with the temperature, the resonance frequency is varied. The temperature around the sensor can be measured by measuring the resonance frequency. The sensor was driven and signals from the sensor were received by using the loop coil with electromagnetic induction.<BR>It was found that a temperature signal can be detected at a distance of 300 mm.

  84. 極低レイノルズ数における磁気マイクロマシンの泳動 Peer-reviewed

    ISHIYAMA Kazushi

    日本応用磁気学会誌 25 (4) 1223-1226 2001

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.25.1223  

    ISSN:0285-0192

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    The swimming properties of a magnetic micro-machine with a spiral structure were examined experimentally and theoretically under very low Reynolds number conditions. It was demonstrated that the micro-machine could swim in a highly viscous fluid with a Reynolds number of 10<sup>-7</sup>. This result suggests that the micro-machine has a great potential for medical applications. It was found that the optimum blade shape of the micro-machine varied with the Reynolds number condition.

  85. Remote temperature sensing system using reverberated magnetic flux Peer-reviewed

    YH Kim, S Hashi, K Ishiyama, KI Arai, M Inoue

    IEEE TRANSACTIONS ON MAGNETICS 36 (5) 3643-3645 2000/09

    Publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

    DOI: 10.1109/20.908927  

    ISSN:0018-9464

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    A remote temperature sensing system was investigated. The system can measure the temperature by applying an external magnetic flux to the sensor and by receiving a flux at the resonant frequency corresponding to the temperature at the sensor. The sensor does not need a power supply within it and is only composed of a temperature sensitive ferrite core and a wound coil. The inductance of the core varied from about 8-18 mH in the temperature region of 35-55 degreesC, The induced voltage, DeltaV by the sensor was about 10 mV for a 260 mm length between the transmitter and receiver. The system was successfully operated in our investigation.

  86. Development of magnetic micro-machine system for use in medical applications

    ISHIYAMA Kazushi, SENDOH Masahiko, YABUKAMI Shin, YAMAZAKI Aya, YAMAGUCHI Masahiro, ARAI KenIchi, HAYASE Toshiyuki

    The proceedings of the JSME annual meeting 2000 309-310 2000

    Publisher: The Japan Society of Mechanical Engineers

    DOI: 10.1299/jsmemecjo.2000.1.0_309  

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    To develop micro-machines for use in medical application, two kinds of spiral-type magnetic micro-machine, which is driven by an external rotational magnetic field, were fabricated. These machines constructed by permanent magnets and spiral blade. It was demonstrated that changing the direction of the rotation planet of the external rotational field could control swimming direction of the swimming type magnetic micro-machine. The radius of the bend depended on the viscosity of the fluid and on the frequency of the external field. The another magnetic micro-machine could run in a gel and even in bovine meat. Running behavior of the machine depend on a frequency and strength of the external field. In addition, it can be detected where position of the magnetic micro-machine by a magnetic motion capture system.

  87. Spiral-type micro-machine for medical applications Peer-reviewed

    K Ishiyama, KI Arai, M Sendoh, A Yamazaki

    MHS 2000: PROCEEDINGS OF THE 2000 INTERNATIONAL SYMPOSIUM ON MICROMECHATRONICS AND HUMAN SCIENCE 65-69 2000

    Publisher: IEEE

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    The spiral-type magnetic micro-machine, which is driven by a rotating magnetic field, is characterized by their wireless operation for swimming. The machine have to swim under the lower Reynolds number (Re) environment, when the machine is downsized and work inside the human body. In this study, using various silicone oils whose kinematic viscosity ranged from 1 to 5x10(6) mm(2)/s, swimming performance of the machine on low Reynolds number was examined. The machine composed of a cylindrical NdFeB magnet could swim in the oils under condition of Re=10(-7). This Reynolds number is same as that of a micro-machine with micron size swimming in the water In addition, the machine could turn by controlling the external rotational magnetic field, therefore the swimming direction of the machine could be controlled. Using these principles, a magnetic micromachine, which can run in a gel, was also fabricated.

  88. 感温フェライトを用いた遠隔温度計測システム Peer-reviewed

    ISHIYAMA Kazushi

    日本応用磁気学会誌 24 (4) 887-890 2000

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.24.887  

    ISSN:0285-0192

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    A remote temperature sensing system was investigated for use, local such as inside the human body. The system was divided into a magnetic generating part, temperature sensing and temperature information generating part, and temperature information receiving part. A ferrite having a low Curie temperature was used in the temperature sensing part. To receive and transmit the temperature information effectively, LC resonance circuits were used in the system. The resonance frequency of 145 kHz to 220 kHz was varied in the range of 58°C to 66°C. From this experiment, we determined that temperature could be measured at the local site using this system.

  89. スパイラル型磁気マイクロマシンのワイヤレス泳動方向制御 Peer-reviewed

    ISHIYAMA Kazushi

    電気学会論文誌A 120-A 2000

  90. Analysis of Swimming Properties and Design of the Spiral-Type Magnetic Micro-Machine Peer-reviewed

    ISHIYAMA Kazushi

    J.Robotics and Mechatronics 12 2000

  91. Strain Effect on Magnetic Properties of Fe-rich Amorphous Films Peer-reviewed

    ISHIYAMA Kazushi

    Ferrites : Proceedings of The Eighth International Conference on Ferrites, The Japan Society of Powder and Powder metallurgy 716-718 2000

  92. Magnetic Actuators for Medical Applications Peer-reviewed

    ISHIYAMA Kazushi

    Ferrites : Proceedings of The Eighth International Conference on Ferrites, The Japan Society of Powder and Powder metallurgy 1099-1101 2000

  93. Wireless Temperature Sensing System Using Temperature Sensitive Ferrite Peer-reviewed

    ISHIYAMA Kazushi

    Ferrites : Proceedings of The Eighth International Conference on Ferrites, The Japan Society of Powder and Powder metallurgy 1114-1116 2000

  94. Effect of rolling direction on magnetic properties in thin silicon sheets

    NAKANO M, ISHIYAMA K, ARAI K. I, FUKUNAGA H

    23 335-335 1999/10

  95. Thin 3% (100) textured silicon steel sheet with low loss Peer-reviewed

    M Nakano, T Kadotani, H Fukunaga, Y Yamashiro, K Ishiyama, KI Arai

    IEEE TRANSACTIONS ON MAGNETICS 35 (5) 3367-3369 1999/09

    Publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

    DOI: 10.1109/20.800526  

    ISSN:0018-9464

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    Magnetic properties of thin 3% (100) textured silicon steel sheets with low loss were investigated. Annealing act 1200 degrees C in sulfur atmosphere enabled us to obtain the thin sheets containing only (100) grains and consequently the coercive force reached 10 A/m. We, further, advanced the production method of thin (100) textured silicon sheets by using sulfur in solution instead of a sulfur atmosphere.

  96. (110) grain growth and magnetic properties of thin grain-oriented 3% silicon steel sheets Peer-reviewed

    M Nakano, H Fukunaga, K Ishiyama, KI Arai

    IEEE TRANSACTIONS ON MAGNETICS 35 (5) 3379-3381 1999/09

    Publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

    DOI: 10.1109/20.800530  

    ISSN:0018-9464

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    (110) grain growth and magnetic properties in thin grain-oriented silicon sheets with ultimately low loss were investigated. A final-annealing at 1150 degrees C for 20min enables us to obtain the thin sheets covered with only (110) grains and consequently the magnetic induction at 800 A/m, B-8, reached 1.9 T.

  97. Magnetic properties of CoZrNb thin films deposited on amorphous SmCo Peer-reviewed

    YH Kim, K Ishiyama, KI Arai

    IEEE TRANSACTIONS ON MAGNETICS 35 (5) 3394-3396 1999/09

    Publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

    DOI: 10.1109/20.800535  

    ISSN:0018-9464

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    Amorphous CoZrNb, thin films were deposited on amorphous SmCo thin films. The amorphous SmCo layer generated magnetic bias field for the soft film, and this bias field was increased as the length of easy direction was reduced. The bias field of 60Oe mas measured for the sample with the dimension 3mm X 0.5mm. The magnetization process of the biased soft film was different from that of a single layer film.

  98. Effect of machine shape on swimming properties of the spiral-type magnetic micro-machine Peer-reviewed

    M Sendoh, N Ajiro, K Ishiyama, M Inoue, KI Arai, T Hayase, J Akedo

    IEEE TRANSACTIONS ON MAGNETICS 35 (5) 3688-3690 1999/09

    Publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

    DOI: 10.1109/20.800632  

    ISSN:0018-9464

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    Effect of a machine shape on swimming propel-ties of the spiral-type magnetic micro-machine was examined by using a finite volume method. The optimum design of the blade shape was obtained by using the results of the simulation. According to the optimum design, the micro-machine was fabricated by a stereolithography. The swimming properties of the machine were agreed well with the analyzed results.

  99. Sensitive Magnetic Field Sensor for Intelligent Ttansportation System Composed of Soft Magntic Film and Integrated Thin-Film Bias Magnet Peer-reviewed

    M.Yamaguchi, M.Takezawa, K.Ishiyama, M.Baba, K.I.Arai, Y.H.Kim, N.Wako, I.Abe

    Transducers'99 Digest of Technical Papers, (1) 602-605 1999/06

  100. Relationship between rolling direction and texture in thin grain-oriented 3% silicon sheets Peer-reviewed

    M Nakano, K Ishiyama, KI Arai, H Fukunaga

    JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS 196 344-345 1999/05

    Publisher: ELSEVIER SCIENCE BV

    DOI: 10.1016/S0304-8853(98)00741-0  

    ISSN:0304-8853

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    We investigated the effect of the rolling direction and the texture of a mother material on the texture of thin sheets. It was found that the [001] orientation of thin silicon sheets is affected by a rolling direction rather than by a texture of the mother material. (C) 1999 Elsevier Science B.V. All rights reserved.

  101. Ultra-low iron loss in new non-oriented silicon steel sheets Peer-reviewed

    M Nakano, T Okamoto, H Fukunaga, Y Yamashiro, K Ishiyama, KI Arai

    JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS 196 341-343 1999/05

    Publisher: ELSEVIER SCIENCE BV

    DOI: 10.1016/S0304-8853(98)00740-9  

    ISSN:0304-8853

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    We report a new method of preparing 30 mu m-thick non-oriented 3% silicon steel sheets covered with only (100) grains. The iron loss at 1.0 T, 50 Hz, was 0.61 W/kg. This value is less than the iron loss of the highest grade conventional non-oriented 3% silicon steels with the thickness 350 mu m (Nippon Steel Corporation 35H270) by approximately 40%. (C) 1999 Elsevier Science B.V. All rights reserved.

  102. Thin 3% (100) silicon steel sheets with ultimate low loss Peer-reviewed

    M. Nakano, T. Kadotani, H. Fukunaga, Y. Yamashiro, K. Ishiyama, K. L. Arai

    Digests of the Intermag Conference 1999

    ISSN:0074-6843

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    Discussed is the successful development of thin (100) silicon steel sheets with ultimate low iron loss. The magnetic loss at 1.0 T and 50 Hz in 0.1 mm-thickness-sheets (0.32 W/kg) is less than that of the conventional one by about 70%.

  103. "スパイラル形状を基本とした泳動型磁気マイクロマシンの泳動特性," Peer-reviewed

    ISHIYAMA Kazushi

    日本応用磁気学会誌 23 (4-2) 1657-1660 1999

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.23.1657  

    ISSN:0285-0192

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    The fundamental swimming properties of spiral-type magnetic micro-machines were investigated in detail by constructing four micro-machines with different structures. These micro-machines are able to swim in various liquids with kinematic viscosities ranging from 1.37 to 1000 mm<sup>2</sup>/s. This result suggests that the micro-machines have potential medical uses. In particular, they can swim against the stream in a liquid whose the velocity is comparable to the that of venous blood.

  104. "有限体積法による磁気マイクロマシン特性の2次元解析," Peer-reviewed

    ISHIYAMA Kazushi

    日本応用磁気学会誌 23 (4-2) 1665-1668 1999

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.23.1665  

    ISSN:0285-0192

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    The swimming properties of magnetic micro-machines with spiral structures were analyzed theoretically by employing the two-dimensional finite volume method. Good agreement between the experimental and theoretical results was obtained. It was demonstrated that the swimming properties of machines depend strongly on the operational environment, including the state of the flow field and machine structure. Thus, there exists an optimum machine structure corresponding to the operation environment, which can be determined from the present analytical results.

  105. Integration of high-frequency carrier-type thin-film magnetic field sensor with SmCo thin-film bias magnet Peer-reviewed

    ISHIYAMA Kazushi

    IEEE Trans.Magnetics 35 (3682-3684) 1999

    DOI: 10.1109/20.800630  

  106. リモート動作可能な磁気アクチュエータの医用応用 Peer-reviewed

    ISHIYAMA Kazushi

    日本AEM学会誌 7 373-378 1999

  107. High frequency carrier type bridge-connected magnetic field sensor Peer-reviewed

    M Takezawa, H Kikuchi, K Suezawa, M Yamaguchi, K Ishiyama, KI Arai

    IEEE TRANSACTIONS ON MAGNETICS 34 (4) 1321-1323 1998/07

    Publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

    DOI: 10.1109/20.706535  

    ISSN:0018-9464

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    This paper discusses the enhancement of the sensitivity of high frequency carrier type magnetic field sensors by using bridge connection of the sensor elements. A high sensitivity of 2.0 V/Oe was achieved at a carrier frequency of 15 MHz.

  108. Effect of rolling condition on textures and magnetic properties in thin grain-oriented silicon steel sheets Peer-reviewed

    M Nakano, K Ishiyama, KI Arai, H Fukunaga

    JOURNAL DE PHYSIQUE IV 8 (P2) 543-546 1998/06

    Publisher: E D P SCIENCES

    ISSN:1155-4339

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    We investigated the effect of rolling conditions on the textures and magnetic properties in order to advance the reduction of iron loss in thin grain-oriented silicon steel sheets which can be produced by using the three-stage rolling method. In this contribution, it was clarified that the sheets are completely covered with highly oriented (110) grains when the amount of the rolling reductions become more than 50 % in all the rolling processes. Consequently, thin silicon steel sheets with the highest value of B-s (the magnetic induction at 800 A/m) can be produced under the same optimum condition.

  109. Trial on-silicon micromagnetoelastic devices Peer-reviewed

    M Takezawa, M Yamaguchi, K Ishiyama, KI Arai

    JOURNAL OF APPLIED PHYSICS 83 (11) 7303-7305 1998/06

    Publisher: AMER INST PHYSICS

    DOI: 10.1063/1.367759  

    ISSN:0021-8979

    eISSN:1089-7550

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    This paper discusses two new kinds of micromagnetoelastic devices made on silicon wafer whose function is to control the permeability of magnetostrictive soft magnetic thin films by voltage-controlled elastic strain. One is piezoelectric type and the other is electrostatic type. Structure, fabrication process, characteristics, and maximum possible output are discussed. The feasibility of these devices has been clarified although the fate of obtained permeability change was less than 1%. These device characteristics could be improved to 11% for piezoelectric type and to 80% for electrostatic type by the optimization of device dimensions and reduction of process damage to the magnetic film. (C) 1998 American Institute of Physics.

  110. "(100)けい素鋼単結晶板の磁わい," Peer-reviewed

    ISHIYAMA Kazushi

    日本応用磁気学会誌 22 (4-2) 645-648 1998

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.22.645  

    ISSN:0285-0192

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    One of the main factors in the acoustic noise of power transformers is thought to be magnetostriction of the cores, because the magnetic flux deviates from the easy axes at the corners of the cores. Therefore, we measured the magnetostriction and observed the domain structure in single crystals of (100) Si-Fe sheets when the easy axes deviated from the exciting direction. Complicated behaviors involving shrinkage and expansion were observed in the measured magnetostriction. In the demagnetized state, 180° domain walls parallel to the [001] direction were observed. When a small field was applied, a [010] domain was generated at the edge of the sample. The [001] and the [010] domains are partitioned by a 90° domain wall, whose movement caused large shrinkage. In a larger field, rotation of the magnetization caused large expansion. Thus, it became clear that large vibrations with magnetostriction were generated at the corners of the core, even if the cube-textured Si-Fe was used as the core's material.

  111. "薄けい素鋼板の磁気特性に及ぼす中間熱処理の条件の影響," Peer-reviewed

    ISHIYAMA Kazushi

    日本応用磁気学会誌 22 (4-2) 653-656 1998

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.22.653  

    ISSN:0285-0192

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    We found that in the three-stage rolling method, control of the intermediate annealing temperatures improves the [001] orientation and makes it possible to reduce the iron loss in silicon steels. The measured iron loss <i>W</i><sub>13/50</sub> for an applied tensile strength of 2 kg/mm<sup>2</sup> was 0.28 W/kg, which is about 50% less than that of conventional (300-μm) grain-oriented silicon steels.

  112. Micro magnetic thin-film sensor using LC resonance Peer-reviewed

    M Takezawa, H Kikuchi, K Ishiyama, M Yamaguchi, KI Arai

    IEEE TRANSACTIONS ON MAGNETICS 33 (5) 3400-3402 1997/09

    Publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

    DOI: 10.1109/20.617957  

    ISSN:0018-9464

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    This paper reports the performance of a new micro magnetic thin-film magnetic field sensor, which makes use of LC resonance of the sensor element as well as the impedance change due to the permeability change of the magnetic film. A large impedance change of 105% was achieved at a carrier frequency of 100 MHz. The large change was realized when the LC resonance frequency of the sensor element was lower than the frequency at which the eddy-current losses increased.

  113. Reduction of iron loss in thin grain-oriented silicon steel sheets Peer-reviewed

    M Nakano, K Ishiyama, KI Arai, H Fukunaga

    IEEE TRANSACTIONS ON MAGNETICS 33 (5) 3754-3756 1997/09

    Publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

    DOI: 10.1109/20.619561  

    ISSN:0018-9464

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    We investigated the effect of the intermediate annealing conditions on the grain textures and the magnetic properties in thin grain-oriented silicon steel sheets produced by the three-stage rolling method. It was found that the lower the intermediate annealing temperature it;, the better the [001] orientation is achieved. In addition, the reduction of the intermediate annealing temperatures improves dc magnetic properties (B-8, He) and enables to reduce the iron loss in thin silicon steels. The measured iron loss W13/50 under the applied tensile strength of 2 kg/mm(2) was 0.28 W/kg, which is less than that of the conventional (300 mu m) grain-oriented silicon steels by;about 50 %.

  114. New production method of 100-mu m-thick grain-oriented 3% silicon steel sheets Peer-reviewed

    M Nakano, K Ishiyama, KI Arai, H Fukunaga

    JOURNAL OF APPLIED PHYSICS 81 (8) 4098-4100 1997/04

    Publisher: AMER INST PHYSICS

    DOI: 10.1063/1.365093  

    ISSN:0021-8979

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    We report a new method of preparing highly oriented 3% silicon steel sheets with a thickness of 100 mu m, which enables us to realize the mass production with existing manufacturing facility. In our new method, a hot-rolled silicon steel is thinned to 100 mu m by a three-step rolling process with intermediate annealings and the (110)[001] is created by the final annealing taking advantage of surface energy. The obtained 100-mu m-thick sheets had the Goss texture and superior soft magnetic properties (the magnetic induction at 800 A/m, B-8 is approximately equal to 1.9 T, the coercive force &lt;4 A/m). In addition, the iron loss W 15/50 at 1.5 T, 50 Hz under the applied tensile strength of 2 kg/mm(2) was 0.53 W/kg. This value is less than that of the conventional (300 mu m) grain-oriented silicon steels by about 37%. (C) 1997 American Institute of Physics.

  115. "100μm厚けい素鋼板の高方位集積化," Peer-reviewed

    ISHIYAMA Kazushi

    日本応用磁気学会誌, 21 (4-2) 593-596 1997

    Publisher: None

    DOI: 10.3379/jmsjmag.21.593  

    ISSN:0285-0192

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    We propose a new method of preparing highly oriented silicon steel sheets with a thickness of 100 μm. Our new method consists of a three-step rolling process and a twostep intermediate annealing process. The final annealing to form a (110) [001] texture takes advantage of the surface energy. The magrietic induction at 800 A/m, B_8 is about 1.9 T, and the coercive force is less than 4 A/m.

  116. "2 方向性けい素鋼単結晶板の磁区構造と磁わい," Peer-reviewed

    ISHIYAMA Kazushi

    日本応用磁気学会誌, 21 (4-2) 597-600 1997

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.21.597  

    ISSN:0285-0192

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    Cube-textured Si-Fe would be useful for applications in which magnetic flux is rotated, because it has two magnetic easy axes that are perpendicular to each other in the steel plane. We measured magnetostriction in the magnetization process for this material when the magnetic easy axis deviated from the exciting direction. Large contraction was observed in larger field than the changing point of inclination of the <i>B-H</i> loop. In addition, when we observed the magnetic domain structure, using Lorentz micrography, a supplementary domain appeared at edge of the sample at the point. We investigated the occurrence of this supplementary domain in detail.

  117. "LC 共振を利用した高感度薄膜磁気センサの可能性," Peer-reviewed

    ISHIYAMA Kazushi

    日本応用磁気学会誌, 21 (4-2) 661-664 1997

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.21.661  

    ISSN:0285-0192

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    This paper reports the performance of a LC resonant magnetic thin-film sensor. The impedance of the sensor changes according to the magnetic field dependence of the permeability and LC resonance of the sensor at high frequencies. To obtain high sensitivity, the conductor layer was covered with insulating layers and magnetic layers. As a result, a large impedance change of 105% was achieved.

  118. Improvement of grain orientation in 100 μm thick silicon steels

    NAKANO M, ISHIYAMA K, ARAI K. I, FUKUNAGA H

    20 331-331 1996/09

  119. The relationship of microstructure and magnetic properties in cold-rolled 6.5% Si-Fe alloy Peer-reviewed

    XF Bi, Y Tanaka, K Sato, KI Arai, K Ishiyama, Y Yamashiro

    IEEE TRANSACTIONS ON MAGNETICS 32 (5) 4818-4820 1996/09

    Publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

    DOI: 10.1109/20.539162  

    ISSN:0018-9464

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    The effect of microstructures on the magnetic properties in the 6.5% Si-Fe alloy was studied. The alloy was subjected to two patterns of heat treatments, and the microstructures were observed by means of TEM. The alloy after an appropriate treatment has shown excellent soft magnetic properties, with the maximum permeability of 7.25x10(4) and the core loss W-10/50 of 0.39 W/kg. The corresponding microstructure was characterized by the extremely fine domains of DO3 order phase existing in B2 order phase. However, the coarsening of the DO3 domains was found to reduce the maximum permeability and increase the core loss of the alloy. It is suggested that the coarsening of the DO3 domains be accompanied with the formation of magnetic contrast around the boundary of the DO3 and B2 phases. Therefore, it is assumed that the phase boundary tends to oppose the displacement of magnetic domain walls due to the existence of the magnetic contrast.

  120. Study on the deformation of 3% Si-Fe single crystal with magnetic field being deviated from [001] Peer-reviewed

    S Hashi, K Ishiyama, KI Arai, M Kawasaki, Y Yamashiro

    IEEE TRANSACTIONS ON MAGNETICS 32 (5) 4848-4850 1996/09

    Publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

    DOI: 10.1109/20.539172  

    ISSN:0018-9464

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    We have investigated the magnetostriction and the magnetization process of 3%Si-Fe single crystal with (110) parallel to the surface, when the direction of magnetization is deviated from [001]. It was found that large contraction and expansion occurred as a result of magnetostriction in the magnetization process, even if the deviation angle was small. Complicated magnetic domain structures were observed with external field being applied. The behavior of magnetostriction corresponds to changes of magnetic domain structure. On the basis of the principle that no magnetic pole appears at domain walls, a model of domain structure is proposed. Using the model, the deformation behavior was explained well.

  121. Micro swimming mechanisms propelled by external magnetic fields Peer-reviewed

    T Honda, KI Arai, K Ishiyama

    IEEE TRANSACTIONS ON MAGNETICS 32 (5) 5085-5087 1996/09

    Publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

    DOI: 10.1109/20.539498  

    ISSN:0018-9464

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    A new type of micro swimming mechanism is proposed for microrobots working in water. It is composed of a small magnet attached to a spiral wire. An external alternating magnetic field causes the magnet to rotate due to magnetic torque. As a result, the mechanism can swim propelled by waves traveling along the spiral. The swimming velocity increases linearly with increasing excitation frequency, and the increasing rate depends on the shape of the spiral. The experimental velocity agreed with the calculation result based upon Lighthill's theory.

  122. Magnetic Properties of 100μm Thick Thin Silicon Steels

    NAKANO Masaki, ISHIYAMA Kazushi, ARAI Ken Ichi, FUKUNAGA Hirotoshi

    1996 (117) 49-56 1996/08

  123. Magnetostriction and Domain Structure of Grain Oriented Silicon Steel Sheets Invited Peer-reviewed

    K. Ishiyama, S. Hashi, M. Kawasaki, K. I. Arai

    Materials Transactions JIM 37 (3) 469-472 1996

    ISSN:0916-1821

  124. "6.5%Si-Fe合金の磁気特性に及ぼす不規則相の影響," Peer-reviewed

    ISHIYAMA Kazushi

    日本応用磁気学会誌, 20 (2) 417-420 1996

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.20.417  

    ISSN:0285-0192

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    A series of heat treatments and TEM observations were performed on a 6.5% Si-Fe alloy. The magnetic properties are dependent on the volume fraction and morphology of the two ordered phases, B2 and DO<sub>3.</sub> The maximum permeability of the specimen reached as high as 7.25 × 10<sup>4</sup> after an appropriate quenching treatment. The microstructure was characterized by the extremely fine DO<sub>3</sub> phase distributed in the B2 phase matrix, with no sharp boundary appearing. It is assumed that a sharp boundary inhibits the movement of the magnetic domain walls.

  125. "方向性珪素鋼板の磁化過程での磁わい," Peer-reviewed

    ISHIYAMA Kazushi

    日本応用磁気学会誌, 20 (2) 441-444 1996

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.20.441  

    ISSN:0285-0192

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    Acoustic noise from power transformers is thought to be produced at the corners of their laminated cores, because the direction of the magnetization vector is not parallel to its [001] axis. To make clear the reason for this problem, we investigated magnetostriction in the magnetization process for grain-oriented silicon steels when the longitudinal direction of sample deviated from [001]. It was found that large contraction or expansion occurred as a result of magnetostriction, even if the deviation angle was small. This behavior was explained as due to reordering of the magnetic domain structure.

  126. "100μm厚珪素鋼板の(110)[001]組織形成," Peer-reviewed

    ISHIYAMA Kazushi

    日本応用磁気学会誌, 20 (2) 445-448 1996

    DOI: 10.3379/jmsjmag.20.445  

  127. "高抵抗Fe-Al-O薄膜の透磁率特性," Peer-reviewed

    ISHIYAMA Kazushi

    日本応用磁気学会誌, 20 (2) 461-464 1996

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.20.461  

    ISSN:0285-0192

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    Fe-Al-O films with a nano-granular structure were fabricated by RF magnetron sputtering. The films exhibit good magnetic softness together with high electrical resistivity.However, they have relatively large deterioration of the initial permeability at high frequencies. In an attempt to explain this peculiar behavior, dispersion of magnetic anisotropy in the films was measured by biaxial Vibrating Sample Magnetometer (VSM), but a theoretical calculation taking account of this anisotropy dispersion resulted in poor agreement with the experiments. Other possibilities such as the existence of a weak ferromagnetic phase, which may dominate the initial permeability, or strong damping of the spin precession, which may occur in the nanogranular structure, were also investigated, but none explained the peculiar behavior of the permeability. The results of this investigation suggest that the dielectric property of the granular film should be studied as a possible cause of this peculiar behavior.

  128. "異方性分散を持つ軟磁性薄膜の磁気特性評価," Peer-reviewed

    ISHIYAMA Kazushi

    日本応用磁気学会誌, 20 (2) 493-496 1996

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.20.493  

    ISSN:0285-0192

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    We used bi-axial VSM to evaluate the anisotropy dispersion of a rotational-field-annealed CoZrNb thin film that shows an almost isotropic <i>M-H</i> curve. It was demonstrated that the isotropic properties of this film resulted from wideangle dispersion of the anisotropy. Using the measured <i>H</i><sub>k</sub> of the film, we calculated the frequency dependence of the permeability, and found that the calculated value agrees well with the measured one. We also calculated the magnetic torque curve, using the measured magnetic anisotropy dispersion of a CuMo-permalloy film. The calculated curve also agrees well with the measured curve.

  129. "Factors affecting grain growth of very thin silicon steel sheets, " Peer-reviewed

    ISHIYAMA Kazushi

    Mater・Sci・forum 204-206 133-142 1996

  130. PRODUCTION OF ULTRA-THIN GRAIN-ORIENTED SILICON STEEL SHEETS Peer-reviewed

    M NAKANO, K ISHIYAMA, KI ARAI

    IEEE TRANSACTIONS ON MAGNETICS 31 (6) 3886-3888 1995/11

    Publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

    DOI: 10.1109/20.489805  

    ISSN:0018-9464

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    Grain texture and magnetic properties of ultra thin silicon steel sheets were investigated. The sheets were produced using two kinds of starting materials. One was conventional grain oriented silicon sleet sheet and the other was hot rolled silicon steel, Ultra thin sheets were obtained by cold rolling with intermediate annealing, ny annealing in a high vacuum a recrystallization using surface energy occurred and very sharp (110)[001] texture was obtained in sheets of 5-8 mu m thick. The B-8 of the ultra thin silicon steel sheets obtained were over 1.95 T.

  131. FABRICATION OF SMALL FLYING MACHINES USING MAGNETIC THIN-FILMS Peer-reviewed

    KI ARAI, W SUGAWARA, K ISHIYAMA, T HONDA, M YAMAGUCHI

    IEEE TRANSACTIONS ON MAGNETICS 31 (6) 3758-3760 1995/11

    Publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

    DOI: 10.1109/20.489762  

    ISSN:0018-9464

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    A small flying machine based upon a new mechanism was realized. The flying machine driven by magnetic torque had hard magnetic films as wings and a soft magnetic wire as a body, respectively. The wing has two hinges, which create different drag during up and down strokes, and produced lifting force. Shape magnetic anisotropy of the body stabilized the attitude. The flying machine new without power supply cables and guides when the alternating magnetic field of more than 400 Oe around 12 Hz was applied.

  132. MEASUREMENT OF ANISOTROPY DISPERSION IN SOFT-MAGNETIC FILMS WITH QUANTITATIVE ESTIMATION Peer-reviewed

    K ISHIYAMA, A TOYODA, KI ARAI, K OKITA

    IEEE TRANSACTIONS ON MAGNETICS 31 (6) 3841-3843 1995/11

    Publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

    DOI: 10.1109/20.489790  

    ISSN:0018-9464

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    A new method of measuring magnetic anisotropy dispersion rising a biaxial VSM was presented. This method made it possible to measure the magnitude and angular dispersion of magnetic anisotropy independently and quantitatively by measuring a reversal of magnetization perpendicular to a magnetic field. Adopting the measured anisotropy dispersion, frequency dependence of permeability for soft magnetic thin film has been calculated.

  133. Measuring Anisotropy Dispersion by Using Biaxial VSM and Estimation of the Permeability. Peer-reviewed

    ISHIYAMA Kazushi

    Journal of Magnetic Society of Japan 19 (20329-332) 1995

    DOI: 10.3379/jmsjmag.19.329  

  134. Recrystallization and Magnetic Properties of Thin Silicon Steels Peer-reviewed

    ISHIYAMA Kazushi

    Journal of Magnetic Society of Japan 19 (2) 433-436 1995

    DOI: 10.3379/jmsjmag.19.433  

  135. Fabricating Microactuators by Using Magnetic Thin Films Peer-reviewed

    ISHIYAMA Kazushi

    Journal of Magnetic Society of Japan 19 (2) 501-504 1995

    DOI: 10.3379/jmsjmag.19.501  

  136. EFFECT OF ANNEALING ATMOSPHERE ON MICROSTRUCTURE AND MAGNETIC-PROPERTIES OF HIGH SI-FE ALLOYS Peer-reviewed

    JM KOO, K ISHIYAMA, KI ARAI

    JOURNAL OF THE JAPAN INSTITUTE OF METALS 58 (5) 571-575 1994/05

    Publisher: JAPAN INST METALS

    DOI: 10.2320/jinstmet1952.58.5_571  

    ISSN:0021-4876

    eISSN:1880-6880

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    Structure and magnetic properties of rapidly solidified 6.5 mass%Si-Fe alloy ribbons were studied by controlling the atmosphere during heat treatment. The ribbons were annealed in three kinds of atmosphere listed as below. (1) in the vacuum atmosphere for 3.6 ks at 1448 K (2) in the sulfur atmosphere for 3.6 ks at 1448 K (3) in the vacuum atmosphere for 180 s at 1373 K and the sulfur atmosphere for 3.6 ks at 1448 K The structure of ribbon, which were showed random structure at as prepared state, was developed into (110) texture by the heat treatment (1). On the contrary, the structure was developed into (100) texture by the heat treatment (2). In the case of the heat treatment (3), the structure of ribbon was also developed into (100) texture and the grain size was large such as 2.5-5 mm, as compared with heat treatment (1) and (2). The coercive force decreased to 2-4 A/m remarkably.

  137. RECENT DEVELOPMENTS OF NEW SOFT-MAGNETIC MATERIALS Peer-reviewed

    KI ARAI, K ISHIYAMA

    JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS 133 (1-3) 233-237 1994/05

    Publisher: ELSEVIER SCIENCE BV

    DOI: 10.1016/0304-8853(94)90534-7  

    ISSN:0304-8853

    eISSN:1873-4766

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    This paper reports three large topics for recent soft magnetic materials: ultrathin grain-oriented silicon steels, nanocrystalline magnetic materials and 6.5 wt% Si-Fe alloy sheets. The ultrathin grain-oriented silicon steels are known to have extremely low iron loss. Recently it has reported the domain width of ultrathin grain-oriented silicon steels can be controlled by changing the grain size, so that very low iron losses can be realized without an additional domain-refining technique. The nanocrystalline magnetic materials are made by recrystallizing amorphous materials. Since the grain size is about 10 nm, the effective magnetic anisotropy is small, so the nanocrystalline materials have fine soft magnetic properties. The 6.5 wt% Si-Fe alloy has small magnetostriction, but has not been manufactured because of its poor ductility. Recently the sheets have been commercially developed and used for high-frequency transformers.

  138. EDDY-CURRENT LOSSES AND NUMBER OF DOMAIN-WALLS WITH RESPECT TO TOTAL NUMBER OF LAYERS FOR VERY THIN 3-PERCENT SI-FE STRIP-WOUND CORES Peer-reviewed

    KI ARAI, YH KIM, M YAMAGUCHI, K ISHIYAMA

    JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS 133 (1-3) 198-200 1994/05

    Publisher: ELSEVIER SCIENCE BV

    DOI: 10.1016/0304-8853(94)90524-X  

    ISSN:0304-8853

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    The relation between the domain wall motion and the eddy current losses of very thin (110)[001] 3% Si-Fe strip-wound cores were investigated. The measured eddy current losses were larger than those estimated using a modified Pry and Bean model in the frequency region 50-500 Hz. It is known that the domain walls of thick (110)[001] 3% Si-Fe strips move nonuniformly in the low-frequency range (0.1-100 Hz), but this frequency range is lower than that usually used for very thin strips. By measuring the flux voltage in every layer, we found that the voltage waveforms were not sinusoidal, even if the secondary voltage waveform of the core was sinusoidal, and the magnitude of the voltage in each layer was not uniform. These results indicate that the domain wall motion of very thin strips is not uniform, even at 50-500 Hz. The nonuniformity of the domain wall motion makes the eddy current losses larger than those estimated by means of the modified Pry and Bean model.

  139. (110) [001] Grain Growth in Silicon Steel Sheets of 30 µm Thickness

    M. Nakano, S. Agatsuma, K. Ishiyama, K. I. Arai

    IEEE Translation Journal on Magnetics in Japan 9 67-72 1994/01/01

    DOI: 10.1109/TJMJ.1994.4565796  

    ISSN:0882-4959

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    Thin grain-oriented silicon steel sheets have the lowest iron loss at a thickness of 30 µm. We observed the recrystallization behavior and magnetic properties of 30 µm thick silicon steel sheets, and compared the results with those of 60 µm thick silicon steel sheets. The recrystallization processes in the two types of sheet were found to be different. The primary recrystallized 30 µm thick silicon steel sheets did not have a strong (110) [001] texture or other orientation; consequently secondary recrystallization did not occur. However, at annealing temperatures above 1050°C, (110) [001] grains grew selectively. Thus we were able to obtain very thin grain-oriented silicon steel sheets with a thickness of 30 µm. © 1994, IEEE. All rights reserved.

  140. Impurity Effect on Cold Roll and Recrystallization Textures of Thin Silicon Steel Sheets. Peer-reviewed

    ISHIYAMA Kazushi

    Journal of Japan Institute of Metals 57 (1) 108 1993

    DOI: 10.2320/jinstmet1952.57.1_108  

  141. Effect of Impurities on Tertiary Recrystallization in Thin 3% Silicon Steel Sheets. Peer-reviewed

    ISHIYAMA Kazushi

    Journal of Japan Institute of Metals 57 (1) 114 1993

    DOI: 10.2320/jinstmet1952.57.1_114  

  142. Factors Affecting Tertiary Recrystallization of Thin Silicon Steel Sheets Peer-reviewed

    ISHIYAMA Kazushi

    Journal of Japan Institute of Metals 57 (1) 119 1993

    DOI: 10.2320/jinstmet1952.57.1_119  

  143. Dynamic Properties of Very Thin 3%Si-Fe Cores in Relation to the Number of Layers Peer-reviewed

    ISHIYAMA Kazushi

    Journal of Magnetic Society of Japan 17 (2) 229 1993

    DOI: 10.3379/jmsjmag.17.229  

  144. Grain Size and Domain Width of a Very Thin 3%Si-Fe Sheet Peer-reviewed

    ISHIYAMA Kazushi

    Journal of Magnetic Society of Japan 17 (2) 225 1993

    DOI: 10.3379/jmsjmag.17.225  

  145. Very Thin Silicon Steel Tertiary Recrystallized by Continuous Annealing Method Peer-reviewed

    ISHIYAMA Kazushi

    Journal of Magnetic Society of Japan 17 (2) 221 1993

    DOI: 10.3379/jmsjmag.17.221  

  146. (110)[001] Grain Growth in Silicon Steel Sheets of 30μm Thickness Peer-reviewed

    ISHIYAMA Kazushi

    Journal of Magnetic Society of Japan 17 (2) 233 1993

    DOI: 10.3379/jmsjmag.17.233  

  147. Magnetostriction of Sputtered Sm-Fe Thin Films Peer-reviewed

    ISHIYAMA Kazushi

    IEEE Transactions on Magnetics 29 (6) 3126 1993

    DOI: 10.1109/20.280878  

  148. Dependence of Magnetostriction of Sputtered Tb-Fe Films on Preparation Conditions. Peer-reviewed

    ISHIYAMA Kazushi

    IEEE Transactions on Magnetics 29 (6) 3129 1993

    DOI: 10.1109/20.280877  

  149. Iron Loss of Grain Size Controlled Very Thin Grain Oriented Silicon Steels Peer-reviewed

    ISHIYAMA Kazushi

    IEEE Transactions on Magnetics 29 (6) 3535 1993

    DOI: 10.1109/20.281221  

  150. EFFECT OF STRESS ON TERTIARY RECRYSTALLIZED SILICON-IRON Peer-reviewed

    A SAITO, K YAMAMOTO, K ISHIYAMA, K ARAI

    JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS 112 (1-3) 229-231 1992/07

    Publisher: ELSEVIER SCIENCE BV

    DOI: 10.1016/0304-8853(92)91160-U  

    ISSN:0304-8853

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    The effects of stress on the magnetization change for tertiary recrystallized silicon iron has been investigated. The processes of magnetization change due to tensile stress at various points on the hysteresis curve have been made clear. This material has an extremely small volume portion of 90-degrees domains compared with high-grade commercial grain-oriented silicon iron sheet.

  151. Relationship between grain size and iron loss of very thin grain oriented silicon steels Peer-reviewed

    ISHIYAMA Kazushi

    The Transactions of the Institute of Electrical Engineers of Japan 112 (6) 1992

    DOI: 10.1541/ieejfms1990.112.6_521  

  152. MAGNETIC-PROPERTIES OF CO-FE ELECTRODEPOSITED ALUMITE FILMS Peer-reviewed

    KI ARAI, HW KANG, K ISHIYAMA

    IEEE TRANSACTIONS ON MAGNETICS 27 (6) 4906-4908 1991/11

    Publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

    DOI: 10.1109/20.278694  

    ISSN:0018-9464

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    The magnetic properties of alumite film in which Co-Fe alloy electrodeposited are investigated with regard to the alloy composition and the geometric structure of the magnetic films. The Co-Fe particles electro-deposited in the alumite film are single phase alloy particles. The Co-Fe alloy electrode-posited films with small pore diameter (150 angstrom) have a large maximum magnetic energy product (BHmax) of about 1.44 MGOe due to the high coercive force, high saturation magnetization and good squareness of the M-H curve. Therefore the Co-Fe alloy electrodeposited film has good possibility for perpendicular magnetic recording media of magnetic rotary encoders.

  153. Special issue/Magnetic recording media by means of wet processes. Perpendicular magnetic recording media using alumite films.

    ARAI Ken-ichi, KANG Hee Woo, ISHIYAMA Kazushi

    Jitsumu Hyomen Gijutsu 42 (3) 291-296 1991

    Publisher: The Surface Finishing Society of Japan

    DOI: 10.4139/sfj.42.291  

    ISSN:0915-1869

  154. Recrystallization and magnetic properties of purfied 3% silicon steels Peer-reviewed

    ISHIYAMA Kazushi

    Journal of Applied Physics 70 (10) 1991

    DOI: 10.1063/1.349986  

  155. MAGNETIC-PROPERTIES OF CO AND CO-FE ELECTRODEPOSITED ALUMITE FILMS Peer-reviewed

    KI ARAI, HW KANG, K ISHIYAMA

    IEEE TRANSACTIONS ON MAGNETICS 26 (5) 1635-1637 1990/09

    Publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

    DOI: 10.1109/20.104472  

    ISSN:0018-9464

  156. MAGNETIC-PROPERTIES OF FE ELECTRODEPOSITED ALUMITE FILMS Peer-reviewed

    KI ARAI, HW KANG, K ISHIYAMA, T KAMIGAKI, TOKUNAGA, I, S YANAGITA, S TONEGAWA, K HAYASAKA

    IEEE TRANSACTIONS ON MAGNETICS 26 (5) 2295-2297 1990/09

    Publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

    DOI: 10.1109/20.104702  

    ISSN:0018-9464

  157. Dynamic domain wall movement of surface scratched silicon steels Peer-reviewed

    ISHIYAMA Kazushi

    IEEE Transactions of Magnetics 26 1990

    DOI: 10.1109/20.104584  

  158. Tertiary recrystallzation and iron loss of ultra thin silicon steels Peer-reviewed

    ISHIYAMA Kazushi

    IEEE Transactions of Magnetics 26 1990

    DOI: 10.1109/20.104585  

  159. Magnetic properties of cobalt electrodeposited anodic oxide magnetic films Peer-reviewed

    Ken Ichi Arai, Yohsuke Ohoka, Kazushi Ishiyama, Hee Woo Kang

    Electronics and Communications in Japan (Part II: Electronics) 73 (6) 100-105 1990

    DOI: 10.1002/ecjb.4420730612  

    ISSN:1520-6432 8756-663X

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    A magnetic film was fabricated by electrodeposition of cobalt in the pores of an aluminum anodic oxide. The dependence of coercive force and magnetic anisotropy energy on the packing density and diameter of the cobalt particles was investigated when the pore diameter was kept constant. The dependence of coercive force on the electrodeposition condition of cobalt was also investigated. The coercive force perpendicular to the film surface decreased when the packing density increased because the c‐axis, which is the axis of easy magnetization in a cobalt crystal, tended to incline to the film surface direction when the packing density increased. Magnetic anisotropy energy depended strongly on packing density. When the packing density was less than 0.26, the direction perpendicular to the film surface became the axis of easy magnetization. The perpendicular magnetic anisotropy energy was smaller than the calculated value of the magnetostatic energy because of the in‐plane orientation of the c‐axis. In a magnetic film with a pore diameter of 200 Å, the perpendicular coercive force was varied from 2000 to 1200 Oe by controlling the pH and the temperature of the cobalt electro‐depositing bath. Copyright © 1990 Wiley Periodicals, Inc., A Wiley Company

  160. Effect of scratching on iron loss of tertiary recrystallized silicon steel Peer-reviewed

    ISHIYAMA Kazushi

    Anales de Fisica B 86 1990

  161. "コバルトを析出させた陽極酸化磁性膜の磁気特性," Peer-reviewed

    ISHIYAMA Kazushi

    電子通信情報学会論文誌C-II, J72C-II (8) 790-794 1989

  162. Iron loss of tertiary recrystallized silicon steel Peer-reviewed

    ISHIYAMA Kazushi

    IEEE Transactions on Magnetics 25 1989

    DOI: 10.1109/20.42487  

  163. Magnetic properties of alumite magnetic films, " Peer-reviewed

    ISHIYAMA Kazushi

    J. Phys. Colloq C8. , 49 1977-1978 1988

  164. Rolled texture and magnetic properties of 3% silicon steel Peer-reviewed

    ISHIYAMA Kazushi

    Journal of Applied Physics 64 (10) 1988

    DOI: 10.1063/1.342369  

Show all ︎Show first 5

Misc. 116

  1. Effect of Negative Permeability of Co-Zr-Nb Film on Crosstalk between Microstrip Lines

    小林拓真, 室賀翔, 田中元志, 遠藤恭, 枦修一郎, 石山和志, 直江正幸

    電子情報通信学会技術研究報告(Web) 121 (6(EMCJ2021 1-6)) 2021

    ISSN:2432-6380

  2. Wireless Magnetic Position-Detection System With Four Excitation Coils

    Yutaro Osaki, Shuichiro Hashi, Shin Yabukami, Hiroyasu Kanetaka, Kazushi Ishiyama

    IEEE SENSORS JOURNAL 17 (14) 4412-4419 2017/07

    Publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

    DOI: 10.1109/JSEN.2017.2707388  

    ISSN:1530-437X

    eISSN:1558-1748

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    For tracking position or motion of objects in small or shielded spaces, our wireless position-detection system using an LC resonant marker is considered to be effective. Generally, detection of the accurate position of the marker is difficult when reduction of the S/N ratio occurs due to the marker posture. To solve this problem, we propose a system with four excitation coils to generate four-directional magnetic fields whose components are different from each other. To evaluate this system, simulations and experiments were conducted for a single excitation coil and for four excitation coils. In the single excitation coil system, position detection was difficult for some postures of the LC marker due to the greatly reduced excitation efficiency of the marker. In contrast, in the four excitation coil system, the excitation strength of the marker was kept for every marker posture, and position detection was performed with high accuracy even when the marker was placed where the excitation was weakest. Therefore, it is possible to detect the position of the marker accurately regardless of its posture by using four excitation coils. By this improvement, our position-detection system is considered to be useful for tracking finger motion in some applications.

  3. Magnetic Noise Suppressor to Facilitate Compatibility Between Power Electronic System and Next Generation RF IC for Telecommunication (Invited) (電磁環境 マグネティックス合同研究会 EMC一般(EMC Joint Workshop, 2017, Singapore))

    Yamaguchi Masahiro, Tanaka Satoshi, Nagata Makoto, Ishiyama Kazushi, Kondo Koichi, Okiyoneda Yasuyuki

    電気学会研究会資料. EMC = The papers of technical meeting on electromagnetic compatibility, IEE Japan 2017 (12) 39-43 2017/05/18

    Publisher: 電気学会

  4. Effects of direction of easy axis and of shape of edge on MI properties

    KIKUCHI Hiroaki, TAKAHASHI Kenta, ONODERA Yuki, TAKAHASHI Yosuke, NAKAI Tomoo, HASHI Shuichiro, ISHIYAMA Kazushi

    2013 (28) 37-41 2013/06/20

  5. Measurement of magnetic field distribution around magnetic head by magneto-optical effect

    TAKAHASHI Junya, HASHI Shuichiro, ISHIYAMA Kazushi

    2012 (81) 83-87 2012/09/24

  6. Application for wireless pump of magnetic actuator

    ISHIYAMA Kazushi, HASHI Shuichiro, KIM SungHoon, AGATSUMA Shigeto

    2012 (81) 55-59 2012/09/24

  7. Composite Film Including Co-ferrite Nanoparticles Prepared by Combination of Electrophoretic Deposition and Electroplating

    HAYASHI Yoshiaki, HASHI Shuichiro, KIM Sung Hoon, ISHIYAMA Kazushi

    2012 (70) 37-41 2012/08/07

  8. Fabrication of GHz band Magnonic crystals with SmCo thin film magnets for magnetic field sensing

    UENO Tomomi, NODA Josho, KANAZAWA Naoki, TAKAGI Hiroyuki, ISHIYAMA Kazushi, INOUE Mitsuteru

    2011 (91) 33-36 2011/11/24

  9. Medical application of wireless pump

    ISHIYAMA Kazushi, KIM SungHoon, HASHI Shuichiro

    2011 (91) 17-21 2011/11/24

  10. Flexible magnetic actuator based biomimetics robots

    KIM Sung Hoon, HASHI Shuichiro, ISHIYAMA Kazushi

    2009 (201) 29-34 2009/12/15

  11. Discussions in the Technical Committee of Micro Magnetic Drive Technology and Applications

    ISHIYAMA Kazushi

    2009 (201) 1-4 2009/12/15

  12. A study of strain sensor using magnetostrictive film

    SUWA Yasuaki, AGATSUMA Shigeto, HASHI Syuichiro, ISHIYAMA Kazushi

    2009 (168) 69-72 2009/12/01

  13. Magnetic Sensors and Actuators for Micro-Robots

    ISHIYAMA Kazushi

    23 (1) 35-36 2008/06/01

    ISSN:0915-6089

  14. Putting Things in the Right Place for Micromachines

    ISHIYAMA K.

    Magnetics Japan 2 (12) 602-605 2007/12/01

    Publisher: 日本磁気学会

    ISSN:1880-7208

  15. Study of the substrates for cantilevered actuators driven by magnetostriction

    YOKOTA Chikako, ISHIYAMA Kazushi, ARAI K. I.

    2006 (167) 85-88 2006/12/19

  16. Study on positional accuracy of wireless motion capture system using LC resonant magnetic marker

    TOYODA M., HASHI S., OHYA M., OKAZAKI Y., YABUKAMI S., ISHIYAMA K., ARAI K. I.

    2006 (167) 61-66 2006/12/19

  17. Trial of the high frequency carrier-type magnetic field sensor using a shape anisotropy

    KATO Tomoki, ISHIYAMA Kazushi, ARAI Ken-Ichi

    2006 (167) 67-71 2006/12/19

  18. Study of a Cantilevered Magnetic Actuator

    YOKOTA Chikako, YAMAZAKI Aya, SENDOH Masahiko, AGATSUMA Shigeto, ISHIYAMA Kazushi, ARAI K. I.

    2006 (88) 47-50 2006/08/03

  19. Enhancement of High-Frequency-Carrier Type Magnetic Field Sensors

    MURAYAMA Yoshitaka, YABUKAMI Shin, OZAWA Tetsuya, ISHIYAMA Kazushi, ARAI Ken-Ichi

    2006 (19) 51-56 2006/03/09

  20. 医療応用を目指した磁気マイクロマシン研究

    荒井賢一, 石山和志

    まぐね 1 65-69 2006

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    通研インポート200703

  21. Examination concerning scaling law of the rotating and driving micro-machine

    ISHIYAMA K., YAMAZAKI A., SENDOH M., ARAI K. I.

    2005 (174) 63-68 2005/12/12

  22. Examination about controlling the low flow rate using Micropump with Magnetic Machine

    HISATOMI Shinichi, YAMAZAKI Aya, ISHIYAMA Kazushi, AGATSUMA Shigeto, SENDOH Masahiko, ARAI Ken Ichi

    2005 (174) 121-125 2005/12/12

  23. Study on Swimming Type Magnetic Micromachine Working inside the Human Body

    KIKUCHI Kenji, YAMAZAKI Aya, ISHIYAMA Kazushi, ARAI Ken Ichi, SENDOH Masahiko

    2005 (174) 127-131 2005/12/12

  24. Basic Properties of Micropump with Magnetic Micromachine

    HISATOMI Shinichi, YAMAZAKI Aya, ISHIYAMA Kazushi, SENDOH Masahiko, YABUKAMI Shin, AGATSUMA Shigeto, MOROOKA Keiko, ARAI Ken Ichi

    2005 (124) 119-123 2005/12/05

  25. High-Frequency-Carrier Type Thin Film Magnetic Field Sensor by controlling annealing temperature and cross sectional shape

    MURAYAMA Y., OZAWA T., YABUKAMI S., ISHIYAMA K., ARAI K. I.

    2005 (50) 13-16 2005/07/14

  26. Micro-Robots for Medical Applications

    ISHIYAMA Kazushi

    142 13-18 2005/05/24

    ISSN:1340-7562

  27. Magnetic Micromachine Moving in a Liver(<Special Issue>the 13th MAGDA Conference)

    SOMA Munehisa, SENDOH Masahiko, ISHIYAMA Kazushi, ARAI Ken-Ichi, Munehisa SOMA, Masahiko SENDOH, Kazushi ISHIYAMA, KenIchi ARAI

    Journal of the Japan Society of Applied Electromagnetics and Mechanics 12 (4) 286-291 2005/02/28

    Publisher: 日本AEM学会

    ISSN:0919-4452

  28. Basic Characteristics of a Magnetic Actuator for Capsule Endoscope

    CHIBA Atsushi, SENDOH Masahiko, ISHIYAMA Kazushi, ARAI KenIchi

    Transactions of the Japanese Society for Medical and Biological Engineering : BME 42 (4) 313-317 2004/12/10

    Publisher: Japanese Society for Medical and Biological Engineering

    ISSN:1347-443X

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    In this paper, the authors propose applying a magnetic actuator to a capsule endoscope. We fabricated a capsule-type magnetic actuator and investigated its moving properties in a silicone tube and in pig intestines. The device consists of a dummy capsule measuring 11 mm in diameter and 40 mm in length, a magnetic actuator composed of a permanent magnet inside the dummy capsule and a 1-mmφ spiral structure outside the capsule. The permanent magnet is magnetized in the direction of the diameter. When a rotational magnetic field is applied, the magnetic actuator rotates and moves wirelessly. In this study, we measured the effect of the spiral shape on the velocity and thrust properties. According to our experimental results using the silicone tube, the optimal actuator was formed with 4 spirals set at a spiral angle of 45 degrees. In the subsequent moving test performed in pig intestines, the actuator traveled a distance of 450 mm to its destination in the large intestine in 150 s, and a distance of 400 mm to its destination in the small intestine in 110s. This result confirms the potential applicability of the actuator as a guidance system for capsule endoscopes.

  29. Fundamental Experiment of a Magnetic Micromachine Capable of Moving in a Liver

    SOMA Munehisa, SENDOH Masahiko, ISHIYAMA Kazushi, SHOJI Koichi, WATANABE Hiroshi, ARAI KenIchi

    Transactions of the Japanese Society for Medical and Biological Engineering : BME 42 (4) 307-312 2004/12/10

    Publisher: Japanese Society for Medical and Biological Engineering

    ISSN:1347-443X

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    Magnetic micromachines are driven by magnetic fields and can be operated wirelessly. The devices themselves require no batteries and no controlling parts or machinery. Given these advantages, micromachines are expected to be applied widely in the medical field. As one example, a micromachine equipped with a heating element for hyperthermia and capable of maneuvering within the human body can be used to provide a new cancer therapy for local hyperthermia. In this study, we fabricated a magnetic micromachine capable of moving in the liver, one of the targets of local hyperthermia. The machine consisted of a cutting tip to cut the liver tissue, a cylindrical permanent magnet and a spiral structure made with a tungsten wire. The magnet was magnetized in the direction of its diameter. The machine was designed with a small diameter of only 0.9mm in order to permit the insertion of an 18G injector. When a rotational magnetic field was applied, the magnet rotated and the spiral structure produced thrust force. The micromachine was able to move a distance of 40 mm in a porcine liver and 45mm in a bovine liver. These results confirm that the micromachine has excellent potential for medical applications.

  30. Wireless Magnetic Actuator for Colon Endoscope Navigation System

    ISHIYAMA K., CHIBA A.

    Journal of Magnetics Society of Japan 28 (11) 1067-1073 2004/11/01

    Publisher: 日本応用磁気学会

    ISSN:0285-0192

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    Recently, medical actuators of various kinds have been reported. We have particularly reported actuators for colon endoscope navigation. Magnetic actuators have the unique feature that they can be moved wirelessly, using external magnetic fields. The magnetic actuator consists of a permanent magnet and a spiral structure. When a rotational magnetic field is applied, the actuator rotates and moves without wired connection. The actuator therefore has a potential use for colon endoscope navigation. In this paper, we show some results compared with other navigation systems.

  31. Fabrication of Micropump with Spiral Magnetic Micromachine

    HISATOMI Shin Ichi, YAMAZAKI Aya, ISHIYAMA Kazushi, ARAI Ken Ichi

    28 546-546 2004/09/21

  32. A Design of High-Frequency-Carrier Type Thin Film Magnetic Field Sensor

    HORIKOSHI N., YABUKAMI S., MURAYAMA Y., OZAWA T., MAWATARI H., ISHIYAMA K., ARAI K. I.

    28 208-208 2004/09/21

  33. Measurement of Low frequency magnetic field using High Frequency carrier-type magnetic sensor

    MURAYAMA Y., OZAWA T., YABUKAMI S., ISHIYAMA K., AGATSUMA S., ARAI K. I.

    28 209-209 2004/09/21

  34. Moving of Magnetic Actuator for a Capsule Endoscope in Intestines of a Pig

    CHIBA A., SENDOH M., ISIYAMA K., ARAI K. I.

    28 332-332 2004/09/21

  35. Fabrication of magnetic micromachine pulling a wire

    KIKUCHI K., YAMAZAKI A., ISHIYAMA K., ARAI K. I.

    28 333-333 2004/09/21

  36. Swimming Properties of Spiral-Type Magnetic Micro-Machines with magnetic thin film

    YAMAZAKI A., SENDOH M., ISHIYAMA K., ARAI K. I.

    2004 (8) 23-27 2004/01/16

  37. Fabrication of a Magnetic Micromachine Capable of Moving in a Liver

    SOMA M., SENDOH M., ISHIYAMA K., ARAI K. I.

    Journal of the Magnetics Society of Japan 28 (3) 441-444 2004

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.28.441  

    ISSN:0285-0192 1880-4004

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    A magnetic micromachine capable of moving in a liver was fabricated. It consisted of a stainless steel tip, a permanent magnet, and a spiral shape made with a tungsten wire. The magnet was magnetized in the direction of its diameter. The diameter of the machine was 0.9 mm, small enough for it to be inserted by means of a medical injector. When a rotational magnetic field was applied, the machine rotated and moved in a liver. According to our experimental results, the strongest force could be exerted by using two spirals, each with an angle of 60°. The micromachine was able to move a distance of 40 mm in a pig's liver. It thus has great potential for medical applications.

  38. Effect of Machine Length on Swimming Properties of Spiral Magnetic Micro-Machine

    Yamazaki A., Sendoh M., Ishiyama K., Arai K. I.

    Journal of the Magnetics Society of Japan 28 (4) 632-635 2004

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.28.632  

    ISSN:0285-0192 1880-4004

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    In previous studies, we examined a magnetic micro-machine composed a magnet and spiral structure. As the magnet was magnetized in the diameter direction, the micro-machine rotated in synchronism with the rotating magnetic field. This time, we fabricated two types of spiral magnetic micro-machines. One had the magnet and the wire of the spiral structure (head type). The other had the wire of the spiral structure (spiral type). We examined the influence of the micro-machine length. As a result, we found that the swimming velocity of the head type micro-machine depended on the machine length. The swimming velocity of the spiral type micro-machine does not depend on the machine length.

  39. Colon endoscope navigation by magnetic actuator and intestine observations

    CHIBA A., SENDOH M., ISHIYAMA K., SUDA Y., ARAI K. I., KOMARU T., SHIRATO K.

    Journal of the Magnetics Society of Japan 28 (3) 433-436 2004

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.28.433  

    ISSN:0285-0192 1880-4004

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    A magnetic actuator for colon endoscope navigation was fabricated. We conducted motion tests of the actuator in the small intestine of a pig and the large intestine of a living dog. The actuator is composed of a permanent magnet and a spiral structure, and is attached to the pointed end of an imitation endoscope. When a rotational magnetic field is applied, the actuator rotates and moves in the intestine. It was able to draw the imitation endoscope forward without injuring and changing the shape of the intestine. This result shows that the actuator has the potential to be use for colon endoscope navigation.

  40. Ferrite films plated on actuators

    NISHIMURA KAZUHIRO, SENDO MASAHIKO, ISHIYAMA KAZUSHI, ARAI KEN'ICHI, UCHIDA HIROHISA, INOUE MITSUTERU

    電気学会マグネティックス研究会資料 MAG-03 (146-151) 29-34 2003/10/31

  41. Colon endoscope navigation by magnetic actuator and intestine observations

    CHIBA A., SENDOH M., ISIYAMA K., SUDA Y., ARAI K. I.

    27 543-543 2003/09/01

    ISSN:1340-8100

  42. Fabrication of magnetic micromachine moving in a liver

    SOMA M., SENDOH M., ISHIYAMA K., ARAI K. I.

    27 131-131 2003/09/01

    ISSN:1340-8100

  43. Swimming Properties of a Spiral-Type Magnetic Micro-Machine to Length

    YAMAZAKI A., SENDOH M., ISHIYAMA K., ARAI K. I.

    27 135-135 2003/09/01

    ISSN:1340-8100

  44. Magnetic biased HFC-type magnetic field sensor with coplanar thin film magnet

    NAKAI T., YAMAGUCHI M., ISHIYAMA K., ARAI K. I.

    27 320-320 2003/09/01

    ISSN:1340-8100

  45. High Frequency Carrier Type Magnetic Field Sensor with Thick Film

    MAWATARI H., MURAYAMA Y., OZAWA T., YABUKAMI S., ISHIYAMA K., ARAI K. I.

    27 318-318 2003/09/01

    ISSN:1340-8100

  46. Fabrication of magnetic actuator for use in a capsule endoscope

    M Sendoh, K Ishiyama, KI Arai

    IEEE TRANSACTIONS ON MAGNETICS 39 (5) 3232-3234 2003/09

    Publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

    DOI: 10.1109/TMAG.2003.816731  

    ISSN:0018-9464

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    In this paper, the authors propose applying a magnetic actuator to a capsule endoscope. Capsule-shaped magnetic actuators were fabricated and in vitro tests were examined. The magnetic actuator was composed of a capsule dummy, a permanent magnet inside the capsule, and a spiral structure. The actuator was rotated and propelled wirelessly by applying an external rotational magnetic field. It was demonstrated that the actuator with 1-mm height spiral could move at 5 mm/s. In addition, the torque required to start rotation was measured. The actuator has great potential for wireless operation of the capsule endoscope.

  47. 電磁エネルギーの実用技術と設計 医用マイクロロボットとそのコントロールシステム

    荒井 賢一, 石山 和志, 仙道 雅彦

    EMC 16 (4) 106-114 2003/08

    Publisher: ミマツコーポレーション

    ISSN:0916-2275

  48. スパイラル型磁気マイクロマシンの3次元泳動特性解析

    山崎 彩, 仙道 雅彦, 石山 和志, 早瀬 敏幸, 荒井 賢一

    日本応用磁気学会誌 27 (3) 142-145 2003

    DOI: 10.3379/jmsjmag.27.142  

    ISSN:0285-0192 1880-4004

  49. Magnetic Actuator Assists in Guiding a Colonoscope

    SENDOH M., ISHIYAMA K., SUDA Y., ARAI K. I.

    Journal of the Magnetics Society of Japan 27 (3) 138-141 2003

    Publisher: The Magnetics Society of Japan

    DOI: 10.3379/jmsjmag.27.138  

    ISSN:0285-0192 1880-4004

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    A magnetic actuator for colonoscope navigation was fabricated. We then examined a motion test using the intestine of a pig. The actuator was composed of a tubular permanent magnet and a spiral structure made of rubber. The magnet was magnetized in the direction of its diameter. The actuator was attached to the end of a simulated endoscope. When a rotational magnetic field is applied, the actuator rotates and moves in the intestine tube. The magnetic actuator can trail two flexible silicone tubes in the small and large intestines of a pig without changing the shape of the intestines. This result suggests that the actuator has great potential for colonoscope navigation.

  50. Fabrication of Micropump With Spiral-Type Magnetic Micromachine

    YAMAZAKI A, SENDOH M, ISHIYAMA K, ARAI K, HAYASE T

    IEEE Trans.Magn. 39 (5,Pt.2) 3289-3291 2003

    DOI: 10.1109/TMAG.2003.816748  

    ISSN:0018-9464

  51. An application of spiral-type magnetic actuator for a guide of a colon endoscope

    ISHIYAMA K., SENDOH M., ARAI K. I.

    2002 180-180 2002/09/11

  52. Recent Progress of Soft and Hard Magnetic Materials : Overview(<The Special Issue> on Recent Progress of Soft and Hard Magnetic Materials)

    ARAI Kenichi, ISHIYAMA Kazushi, Kenichi ARAI, Kazushi ISHIYAMA

    10 (3) 253-256 2002/09/10

    Publisher: 日本AEM学会

    ISSN:0919-4452

  53. Futures of micro-magnetic technology for medical and welfare field

    ARAI K. I., ISHIYAMA K., YABUKAMI S., YAMAGUCHI M.

    26 78-79 2002/09/01

    ISSN:1340-8100

  54. Calefactory area of hyperthermia using two or more heaters

    SHIMIZU J., SATO F., MATSUKI H., SATO T., SENDOH M., ISHIYAMA K., ARAI K.

    26 367-367 2002/09/01

    ISSN:1340-8100

  55. Fabrication of magnetic actuator assists a colon endoscope in guiding

    SENDOH M., ISHIYAMA K., SUDA Y., ARAI K. I.

    26 324-324 2002/09/01

    ISSN:1340-8100

  56. Application of magnetic micro-machine by low temperature ferrite plating technique

    NISHIMURA K, SENDOH M, ISHIYAMA K, ARAI K, INOUE M

    26 360-360 2002/09/01

    DOI: 10.3379/jmsjmag.27.681  

    ISSN:1340-8100

  57. Application of Spiral-Type Magnetic Actuator for Colonoscope Navigation

    ISHIYAMA Kazushi, SENDOH Masahiko, SUDA Yuji, ARAI Ken Ichi

    2002 (101) 25-30 2002/08/27

  58. Development of magnetic micro-machine coated by ferrite plating

    NISHIMURA Kazuhiro, SENDOH Masahiko, ISHIYAMA Kazushi, ARAI Ken Ichi, INOUE Mitsuteru

    2002 (101) 31-36 2002/08/27

  59. Application of ferromagnetic film to micromachines Invited

    M. Yamaguchi, K. Ishiyama, K. I. Arai

    Materials Science and Technology 39 (4) 146-149 2002/08

  60. Magnetic micromachines for medical field applications

    ISHIYAMA K., ARAI K. I.

    123 95-100 2002/02/07

    ISSN:1340-7562

  61. Application of micro-machine by ferrite plating technique II

    NISHIMURA Kazuhiro, SENDOH Masahiko, ISHIYAMA Kazushi, ARAI Ken Ichi, ABE Masanori, INOUE Mitsuteru

    2002 (9) 29-32 2002/02/01

  62. 応用事例 高周波キャリア型センサー/MEMS (特集 応用広がる磁性材料)

    荒井 賢一, 石山 和志

    工業材料 49 (12) 52-55 2001/12

    Publisher: 日刊工業新聞社

    ISSN:0452-2834

  63. Analysis of properties of miniature magnetic swimming machine

    ISHIYAMA K., YAMAZAKI A., SENDOH M., HAYASE T., ARAI K. I.

    2001 431-431 2001/09/21

  64. Fabrication of Magnetic Micro-Machine with heating device

    SENDOH M., ISHIYAMA K., ARAI K. I., SATO F., JOJO M., MATSUKI H.

    25 203-203 2001/09/01

    ISSN:1340-8100

  65. Bending of guide-wire by magnetic torque

    ISHIYAMA K., ARAI K. I.

    25 321-321 2001/09/01

    ISSN:1340-8100

  66. Fabrication and multi-driving of Magnetic Micro-Machine running in a gel

    SENDOH M., ISHIYAMA K., ARAI K. I.

    25 320-320 2001/09/01

    ISSN:1340-8100

  67. Analysis of swimming properties of the miniature magnetic micromachine

    YAMAZAKI A., SENDOH M., ISHIYAMA K., HAYASE T., ARAI K. I.

    25 318-318 2001/09/01

    ISSN:1340-8100

  68. Starting Characteristics of Swimming Type Magnetic Micro-Machine

    SENDOH M., ISHIYAMA K., YAMAGUCHI M., ARAI K. I.

    25 319-319 2001/09/01

    ISSN:1340-8100

  69. Anisotropy control by inverse magnetostrictive effect and application of the strain sensor

    IMAMURA K., ISHIYAMA K., ARAI K. I.

    2000 (326) 23-28 2000/12/20

  70. Wireless temperature sensing system utilizing magnetic field

    HASHI Shuichiro, ISHIYAMA Kazushi, ARAI Ken Ichi, KIM Young Hak, INOUE Mitsuteru, OKAZAKI Yasuo, YANASE Shunji

    2000 (283) 57-61 2000/12/07

  71. A study on miniaturization of spiral-type magnetic micro-machine

    SENDOH M., YAMAZAKI A, ISHIYAMA K., ARAI K. I., INOUE Mitsuteru, HAYASE Toshiyuki

    2000 (283) 39-44 2000/12/07

  72. Starting characteristics of spiral-type magnetic micro-machine

    SENDOH M., ISHIYAMA K., YAMAGUCHI M., ARAI K. I.

    2000 (237) 55-60 2000/11/08

  73. Application of the strain sensor by magneto-elastic effect

    IMAMURA K., SHIN K. H., ISHIYAMA K., INOUE M., ARAI K. I.

    2000 (187) 21-26 2000/09/28

  74. Magnetoelastic strain sensor onto flexible substrates

    IMAMURA K., SHIN K. H., ISHIYAMA K., INOUE M., ARAI K. I.

    24 206-206 2000/09/01

    ISSN:1340-8100

  75. Swimming of the magnetic micromachine in low Reynolds number

    SENDOH M., YAMAZAKI A., ISHIYAMA K., INOUE M., HAYASE T., ARAI K. I.

    24 349-349 2000/09/01

    ISSN:1340-8100

  76. Swimming properties of the spiral-type magnetic micro-machines on high viscosity

    YAMAZAKI A., SENDOH M., ISHIYAMA K., ARAI K. I., INOUE M., HAYASE T.

    2000 (75) 13-18 2000/04/26

  77. Controlling of the swimming direction and motion in the gel of the spiral-type magnetic micro-machines

    SENDOH M., YAMAZAKI A., ISHIYAMA K., ARAI K. I., INOUE M.

    2000 (62) 67-72 2000/03/07

  78. Sensor Applications of Fe-base Amorphous Films

    SHIN Kwang-Ho, IMAMURA Kouki, MAWARITATE Takuma, ISHIYAMA Kazushi, INOUE Mitsuteru, ARAI Ken-Ichi

    2000 (1) 13-18 2000/02/07

  79. Fabrication of Transmissive Small-Sized High Efficiency Magnetic AC Marker

    AJIRO Noriyuki, HASHI Syuichiro, YABUKAMI Shin, ISHIYAMA Kazushi, YAMAGUCHI Masahiro, ARAI KenIchi

    Conference on Information, Intelligence and Precision Equipment : IIP 120-124 2000

    Publisher: The Japan Society of Mechanical Engineers

    More details Close

    We design small magnetic AC markers and investigate its external magnetic field around a marker. We fabricate several AC markers (12.5mm-length, cross sectional are of marker was 15(mm)^2). Measured field of markers is agreed with theoretical field calculated by Biot-Savart's low. External field was about (10)^<-3> Oe, when we applied 1.5V at 425kHz and the distance between marker and sensor was 100mm.

  80. Remote Temperature sensing system

    KIM Y. H., ISHIYAMA K., INOUE M., ARAI K. I.

    23 157-157 1999/10/01

  81. Steering properties of spiral-type magnetic micro-machine

    SENDOH M., YAMAZAKI A., ISHIYAMA K., ARAI K. I., INOUE M.

    23 160-160 1999/10/01

  82. Thermo-magnetic properties of FeRhIr/Ag/Fe multilayer thin films

    HASHI S., ISHIYAMA K., INOUE M., ARAI K. I.

    1999 381-381 1999/09/08

  83. Remote measurement system of temperature

    KIM Y. H., ISHIYAMA K., INOUE M., ARAI K. I.

    1999 399-399 1999/09/08

  84. Magnetic Properties of FeRhIr/Ag/Fe/Ag Multilayer Films (2)

    HASHI Shuichiro, INOUE Mitsuteru, ISHIYAMA Kazushi, ARAI Ken Ichi

    1999 (81) 39-44 1999/07/30

  85. Controlling of the swimming direction and motion in the gel of the spiral-type magnetic micro-machines

    SENDOH M., YAMAZAKI A., ISHIYAMA K., ARAI K. I., INOUE M.

    1999 (36) 55-60 1999/05/25

  86. Effect of machine shape on swimming properties of the spiral-type magnetic micro machine

    SENDOH M., AJIRO N., ISHIYAMA K., INOUE M., ARAI K. I., HAYASE T.

    1998 (238) 1-6 1998/12/15

  87. Control of Bias Field to High Frequency Carrier Type Thin-Film Magnetic Field Sensor by Using SmCo Thin-Film Magnet

    TAKEZAWA M., KIM Y. H., ISHIYAMA K., BABA M., YAMAGUCHI M., ARAI K. I., WAKO N., ABE I.

    1998 (238) 71-76 1998/12/15

  88. Magnetic properties and structures of sputtered SmCo films

    KIM Young Hak, ISHIYAMA Kazushi, ARAI Ken Ichi

    1998 (216) 33-36 1998/12/02

  89. 医用磁気マイクロマシンと超高感度磁界センサ Invited

    荒井賢一, 井上光輝, 山口正洋, 石山和志

    日本応用磁気学会研究会資料 107 41-48 1998/11

    ISSN:1340-7562

  90. Fundamental properties of spiral-type magnetic micro-machines

    SENDOH M., ISHIYAMA K., INOUE M., ARAI K. I.

    22 294-a-294-b 1998/09/01

  91. Magnetization Process of Fe-Si Single Crystal sheets

    HASHI Shuichiro, ISHIYAMA Kazushi, AGATSUMA Shigeto, ARAI Ken Ichi, YAMASHIRO Yasumasa

    MAG 1998 (53) 15-20 1998/06/12

  92. Medical Applications of Magnetic Micro-machines, Aiming for a Realization of Intelligent Magnetic Micro-robots for Medicine and Surgery

    ARAI K. I., INOUE M., YAMAGUCHI M., ISHIYAMA K., YAMADA S., TAKAHASHI A., ISHIBASHI T., TAKAI Y.

    1997 (171) 47-51 1997/11/25

  93. High frequency carrier type sensor using bridge circuit

    TAKEZAWA M., KIKUCHI H., SUEZAWA K., ISHIYAMA K., YAMAGUCHI M., ARAI K. I.

    21 103-103 1997/10/01

  94. Magnetostriction of(100)Si-Fe single crystal with magnetic field being applied

    HASHI S., ISHIYAMA K., AGATSUMA S., ARAI K. I., YAMASHIRO Y.

    21 143-143 1997/10/01

  95. 研究グループ紹介 東北大学電気通信研究所 物性機能デバイス研究部門 スピンエレクトロニクス研究分野

    荒井 賢一, 山口 正洋, 石山 和志, 本田 崇

    電気学会論文誌. A, 基礎・材料・共通部門誌 = The transactions of the Institute of Electrical Engineers of Japan. A, A publication of Fundamentals and Materials Society 117 (3) 337-337 1997/03

    ISSN:0385-4205

  96. Relationship Between Atmosphere Annealing and Magnetic Properties of Non-oriented Silicon Steel

    HUAN Bo Ying, TOHMA Tsugutaka, ARAKAKI Yoshifumi, YAMAMOTO Ken-ichi, YAMASHIRO Yasumasa, KAIDO Tsutumu, HASHI Shu-ichiro, ISHIYAMA Kazuhsi, ARAI Ken Ichi

    1996 (235) 1-10 1996/12/09

  97. Domain structure of (100) textured Si-Fe single crystals

    HASHI Shuichiro, ISHIYAMA Kazushi, ARAI Ken Ichi, YAMASHIRO Yasumasa, ARAI Satoshi

    1996 (235) 11-20 1996/12/09

  98. Sensitive magnetic thin film sensor using LC resonance

    TAKEZAWA M., NAKAGAWA H., KIKUCHI H., AGATSUMA S., ISHIYAMA K., YAMAGUCHI M., ARAI K. I.

    20 45-45 1996/09/01

  99. Magnetostriction and domain structure of cube-oriented Si-Fe with magnetic field being applied

    HASHI S., ISHIYAMA K., AGATSUMA S., ARAI K. I., YAMASHIRO Y., ARAI S.

    20 332-332 1996/09/01

  100. Change of Coercivity with the Formation of Ordering Phases in High-Si Content Fe-Si Alloys

    BI Xiao-fang, ISHIYAMA Kazushi, ARAI Ken Ichi

    1996 (117) 57-64 1996/08/02

  101. 超磁歪材料 (特集 磁性体セラミックス)

    荒井 賢一, 石山 和志

    ニュ-セラミックス 9 (6) 1-4 1996/06

    Publisher: ティ-・アイ・シィ-

    ISSN:0916-4057

  102. Magnetic properties of 3%Si-Fe thin sheets annealed in Ar atmosphere

    Y Yamashiro, A Yonesu, S Hashi, K Ishiyama, KI Arai

    JOURNAL OF APPLIED PHYSICS 79 (8) 4574-4574 1996/04

    Publisher: AMER INST PHYSICS

    ISSN:0021-8979

  103. 蝶のように,精子のように,カニのように--磁性材料を用いたマイクロロボット (<特集>材料と人間のスマ-トな関係(中))

    荒井 賢一, 石山 和志, 本田 崇

    バウンダリ- 12 (4) 10-13 1996/04

    Publisher: コンパス社

    ISSN:0916-2402

  104. 飛行型磁気アクチュエータの寸法と飛行動作

    菅原 渉, 本田 崇, 荒井 賢一, 石山 和志

    電気学会研究会資料. MAG, マグネティックス研究会 1995 (150) 19-25 1995/11/30

  105. 高磁歪薄膜を用いた微小走行機構に関する研究

    本田 崇, 荒井 賢一, 石山 和志

    電気学会研究会資料. MAG, マグネティックス研究会 1995 (150) 11-18 1995/11/30

  106. Magnetoelastic device using magnetic and dielectric films

    TAKEZAWA M., ISHIYAMA K., ARAI K. I.

    19 425-425 1995/09/01

  107. Measurement of large angler magnetic anisotropy dispersion

    ISHIYAMA K., TOYODA A., ARAI K. I.

    19 376-376 1995/09/01

  108. Construction of (110)[001] texture in 100μm thick silicon steels

    NAKANO M., ISHIYAMA K., ARAI K. I., FUKUNAGA H.

    19 70-70 1995/09/01

  109. Effect of ordering on the magnetic properties of 6.5%Si-Fe alloys

    BI X. F., TANAKA Y., SATO K., ARAI K. I., ISHIYAMA K.

    19 67-67 1995/09/01

  110. Magnetostriction of 3%Si-Fe with magnetic field being applied

    HASHI S., KAWASAKI M., ARAI K. I., ISHIYAMA K., BI X. F.

    19 68-68 1995/09/01

  111. 2軸VSMで測定された異方性分散と磁気トルク曲線との関係

    石山 和志, 荒井 賢一

    電気学会研究会資料. MAG, マグネティックス研究会 1995 (80) 1-6 1995/07/18

  112. マイクロ磁気アクチュエ-タの開発-コ-ドレスで歩く,飛ぶ-

    荒井 賢一, 石山 和志, 山口 正洋

    日本機械学会誌 98 (918) 421-421 1995/05/05

    Publisher: 一般社団法人日本機械学会

    ISSN:0021-4728

  113. 3%Si-Fe(110)単結晶板の磁化過程と磁歪

    河崎 正利, 石山 和志, 荒井 賢一

    電気学会研究会資料. MAG, マグネティックス研究会 1995 (12) 57-65 1995/01/27

  114. Grain growth and magnetic properties of thin silicon steels

    NAKANO M., ISHIYAMA K., ARAI K. I.

    1995 (1) 77-83 1995/01/26

  115. マグネスティックスの動向と将来展望--スピニクス特別研究会から

    荒井 賢一, 一ノ倉 理, 石山 和志

    東北大学電通談話会記録 62 (2) p292-294 1994/03

    Publisher: 東北大学電気通信研究所工学研究会

    ISSN:0385-7719

  116. 薄珪素鋼板の3次再結晶と磁気特性

    荒井 賢一, 石山 和志

    日本金属学会会報 31 (5) p429-435 1992/05

    Publisher: 日本金属学会

    ISSN:0021-4426

Show all ︎Show first 5

Research Projects 22

  1. Control of spin flow using three-dimensional artificial magnetic lattice and its application to spin wave integrated devices

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (B)

    Institution: Tohoku University

    2023/04/01 - 2026/03/31

  2. Flow control of spin wave using two-dimensional magnonic crystals and application of integrated spin wave circuits

    Inoue Mitsuteru

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (A)

    Institution: Toyohashi University of Technology

    2019/04/01 - 2022/03/31

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    Magnetic materials with artificial structures on the nanometer scale are called artificial magnetic lattices, and a method to control spin waves flowing in the magnetic materials is expected to create the next generation of computing devices. In this study, we fabricated a device called a two-dimensional magnonic crystal in the artificial magnetic lattices. The planned operation was observed, and the plan for further efficiency and miniaturization of spin-wave devices was also presented.

  3. Developement and application of wireless haptic interface using magnetics

    HASHI SHUICHIRO

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (B)

    Institution: Tohoku University

    2018/04/01 - 2021/03/31

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    By combining the 3D magnetic field vector control system and the infrared motion sensor, we constructed a wireless haptic system that can feedback-control the frequency and magnetic field strength of the magnetic field vector according to the movement of the finger attached with a small magnet. In addition, for purpose of presenting the surface roughness feeling by the system, the roughness feeling was presented by reproducing the displacement of the finger surface when the finger traces a certain surface by the magnet vibration. By detecting the speed of the finger and feeding it back, a magnetic field with a frequency proportional to it was output, and a surface with a virtually constant roughness was reproduced. As a result, when the finger was moved so that the output magnetic field was 20 to 50 Hz, a feeling of surface roughness could be felt.

  4. New measuring system for low-invasive high frequency magnetic field

    ISHIYAMA Kazushi

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Challenging Research (Exploratory)

    Institution: Tohoku University

    2017/06/30 - 2019/03/31

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    I worked on the method using the magneto-optical effect as a new measurement method of removing metals from the vicinity of the measurement object. Here, in order to improve the sensitivity, I proposed a new modulation scheme of pulse laser and obtained high sensitivity. Using this method, we succeeded in visualizing the leakage magnetic field in the vicinity of the power amplifier chip. In addition, I made a portable prototype, and demonstrated it at the exhibition.

  5. Enhancement of electromagnetic nondestructive evaluation technique using thin-film magnetoimpedance sensor with domain wall motion at low frequency

    Kikuchi Hiroaki, ISHIYAMA kazushi, HASHI shuichiro, YABUKAMI shin, TAKEZAWA masaaki

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (B)

    Institution: Iwate University

    2016/04/01 - 2019/03/31

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    The anomalous phenomena appeared on thin-film magnetoimpedance sensor element at a relatively lower frequency was analyzed theoretically based on a domain wall equation and discussed by combined with experimental results, which clarified that the phenomena is attributed to domain wall resonance. Moreover, we demonstrated the potential of high sensitive magnetic field sensor at lower frequency using the phenomena. Related to thin-film magnetoimpedance sensor, we also clarified that a bias direct current is effective to improve sensitivity. The bias direct current induces asymmetric impedance properties, which is explained by the effects of cross sectional shape of an element.

  6. Anisotropy control by inverse magnetostriction for electrical steel for motors with low loss

    ishiyama kazushi

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (B)

    Institution: Tohoku University

    2014/04/01 - 2017/03/31

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    In order to reduce the iron loss of electrical steel for motors, we have to control the magnetic easy axes which orient to thick-direction of the electrical steels due to random orientation of crystal grains. An in-plane eddy current loss associated with thick-direction change of magnetic flux will be reduced when the thick-direction components of the magnetization can be turned toward in-plane of the electrical steels. Therefore, to obtain a basic relation, we investigated magnetic properties of electrical steels under uniform in-plane stress.As a result, it is clearly observed that the magnetization increases with tensile stress, and decreases with compressive stress. It is expected that the magnetizations of thick-direction were rotated to in-plane by applying tensile stress. These results shows the proposed method can reduce the iron loss of the electrical steels.

  7. Development of miniaturized magnetic field sensor with higher sensitivity using inclined magnetic domain and its application for detection of localized weak field

    Kikuchi Hiroaki, ISHIYAMA KAZUSHI, HASHI SHUICHIRO, MATSUO TETSUJI, TAKEZAWA MASAAKI

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (B)

    Institution: Iwate University

    2013/04/01 - 2016/03/31

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    We tried to improve the sensitivity of a magnetic field sensor using thin-filmed ferromagnetic material and to miniaturize the sensor element. The effects of the anisotropy direction on the sensor behaviors were investigated, and the mechanism of discontinuous jump which is observed on the elements having inclined magnetic domain was clarified. The influence of demagnetizing effect was also investigated; the optimum shape was obtained and then the element having 30 micro-meters long were demonstrated. For the applications of nondestructive testing, the behaviors of transformations into ferromagnetic on SUS304 steel and Inconel600 alloy were clarified. The obtained results indicate a potential of local nondestructive testing using magnetism.

  8. Proposal of new technique to disperse magnetic beads

    ISHIYAMA KAZUSHI

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Challenging Exploratory Research

    Institution: Tohoku University

    2013/04/01 - 2015/03/31

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    I proposed and experimentally confirmed the new technique to scatter magnetic beads (fine particles) that expected to use in vivo for drug delivery. As a result, I succeeded in scattering beads using the individual rotary torque of each bead by applying a rotating magnetic field using a material of large magnetic anisotropy as the beads and found the new technique could control the dispersion of the beads for the first time.

  9. Establishment of anisotropy control method of the magnetostrictive thin film using stress induced by difference in thermal expansion and their application for highly sensitive strain sensor.

    HASHI Shuichiro, ISHIYAMA Kazushi

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Challenging Exploratory Research

    Institution: Tohoku University

    2012/04/01 - 2014/03/31

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    In this study, for a soft magnetostrictive thin film (FeSiB), uniaxial anisotropy control method using a difference of thermal expansion coefficients of layered structure composed of other nonmagnetic film (Mo) was studied for realizing high sensitive strain sensor. When the film is subjected to annealing to release a residual stress, the differences of the thermal expansion coefficient of the magnetic film and nonmagnetic film produce an inner stress to each other. The inner stress can induce anisotropy of the magnetic film to arbitrary direction due to the inverse magnetostriction effect. It is found that the uniaxial anisotropy is induced to width direction of the rectangular Mo layer. In addition, it was observed that as the major axis of the rectangular Mo under layer was lengthened, the in-plane uniaxial anisotropy of the FeSiB film was gradually strengthened. Furthermore, the anisotropy of FeSiB induced radially of a ring shape sample using this method was observed.

  10. Development of contactless 3D wireless track-pad

    HASHI Shuichiro, ISHIYAMA Kazushi

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (B)

    Institution: Tohoku University

    2011/04/01 - 2014/03/31

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    In this study, we proposed and developed a wireless magnetic position sensing system that uses LC resonant magnetic markers (LC markers), which is considered as a useful candidate of an input device of fingers motion for a virtual environment. The measurement apparatus composed of multi channels A/D convertors, which has 32 simultaneous analog inputs at 4 MS/s per channel with 16-bit resolution, was constructed. According to evaluation result, the total capturing speed of the system was around 100 Hz (one capturing per second) for two markers detection under synchronized operation of 32 A/D convertors. In addition, the capturing speed are 53 Hz for five LC markers and 20 Hz for ten LC markers.

  11. Study on the interaction between magnetic domains and lattice defects and development of measurement technique for domain movement and magnetic flux changes

    KIKUCHI HIROAKI, ISHIYAMA Kazushi, HASHI Shuichiro

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Challenging Exploratory Research

    Institution: Iwate University

    2011 - 2013

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    In this study, a simultaneous measurement system for observation of domain wall movement and detection of induced voltage at pickup coil was developed. On the other hand, the relationships between magnetic domains and lattice defects were clarified experimentally when the micro lattice defects were introduced into the specimen. The defects pinned domain walls and affect the configurations of magnetic domains and behaviors of domain wall movements. The feasibility of controlling the local domain structures and local magnetic characteristics was indicated.

  12. Development of the human motor function support system

    HASHI Shuichiro, ISHIYAMA Kazushi, YABUKAMI Shin, ARAI Ken ichi

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (B)

    2007 - 2009

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    Basic way for controlling robot arms from wireless motion capture system using LC resonant magnetic marker was established. The prototype system was also developed. A remarkable feature is that the developed technique can detect the motion of a living body without stress and pain. The technique, which will bring about progress on controllability and operationality of a machine, is considered to be useful for various technical fields.

  13. Development of Motion Capture System of Wireless Markers for Irradiation

    YABUKAMI Shin, TAKAI Yoshihiro, KANETAKA Hiroyasu

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (B)

    Institution: Tohoku Gakuin University

    2006 - 2008

  14. High sensitive magnetic field sensing system for measurement of bio-magnetic signal at room temperature

    ARAI Ken ichi, ISHIYAMA Kazushi, YABUKAMI Shin, IMAE Michito, HANADO Yuko

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (A)

    Institution: Tohoku University

    2004 - 2005

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    A highly sensitive magnetic field sensor operating at room temperature shows promise for non-destructive, biomagnetic measurement (such as MCG or MEG). High frequency carrier type sensors have potential for high sensitivity, as in SQUID (Superconducting Quantum Interference Devices). In the present study we developed a very sensitive high-frequency carrier-type magnetic field sensor with a sub-pT resolution using a resonating transmission line-type sensor element since high impedance change can be obtained with such a sensor. The CoNbZr film was deposited by RF sputtering, and a low anisotropy field of 0.8 Oe was applied by annealing. The CoNbZr film thickness of 4 micro m was found to be the optimum value by which to obtain the highest impedance change (dZ/dH). Carrier current flows in the Cu meander pattern, not in CoNbZr film, so the sensor is different from conventional GMI senors in that point. A small AC magnetic field was applied to the sensor element and a very small AM signal was detected using a carrier suppressing circuit. The experiments were carried out in a magnetically shielded room. A resolution of 0.7pT per square root Hz was obtained at 501kHz. The detectable magnetic field was limited by the chaotic noise caused by nonlinear magnetic excitation. A resolution of about 2pT per squire root Hz was obtained at 1kHz and a resolution of about 80pT per square root Hz was obtained at 45Hz.

  15. PLD法によるNdFeB厚膜磁石の低温プロセス作製と医療用マイクロマシンへの応用

    中野 正基, 福永 博俊, 石山 和志, 荒井 賢一

    Offer Organization: 日本学術振興会

    System: 科学研究費助成事業

    Category: 萌芽研究

    Institution: 長崎大学

    2003 - 2004

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    本研究は、レーザアブレーション法を用いたNd-Fe-B系磁石厚膜の作製において、例えば「プラズマ」のような熱エネルギー以外のエネルギーを利用した「低温プロセス」による試料の作製を、検討した。本研究を進めるに当たり、具体的には以下の2点を主に考慮した。 (1)酸素含有量・チェンバ内壁からのガス流失を極力抑制し、活性の高いNd元素の酸化を抑制するため、「200mm径の小型チェンバ」を設計作製するとともに、「超高純度のArガス雰囲気中」でプラズマを誘起し、そのプラズマ内をNd-Fe-B系磁石膜の構成粒子を通過させることにより、低温プロセスでのNd-Fe-B系磁石膜の結晶化ならびに磁気特性の向上について検討した。 (2)更に上述したNd-Fe-B厚膜磁石の「磁気特性」・「微細構造」などを以下の装置を用い評価・観察した。 @磁気特性の評価(本研究室既存:VSM装置) @結晶構造の測定(本学既存:X線回折装置) @微細構造の観察(本学既存:SEM,TEM) @組成分析(本学既存:ESCA,他機関:ICP) 現在のところ、プラズマを利用した上記の作製において、優れた硬磁気特性の発現には至っていない。この原因として、ターゲットから飛び出した原子・イオンなどの粒子が、光励起とともに熱的にも励起されており、チェンバ内の微量な酸素原子と容易に結びつく(酸化する)ためと考えられる。しかしながら、その一方で、一部の手法において、熱処理を施すことなく結晶化する試料も観測され、今後、基板上への成膜室と低温プロセスを実現する部屋の分割化などを鑑みて、本研究の更なる発展を試みる予定である。

  16. 極微小・高Q集積化RF強磁性薄膜インダクタ

    山口 正洋, ぺい 碩, 池田 愼治, 金 基ひょん, 薮上 信, 石山 和志, 荒井 賢一

    Offer Organization: 日本学術振興会

    System: 科学研究費助成事業

    Category: 特定領域研究

    Institution: 東北大学

    2001 - 2003

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    まず,昨年度完成し製品化も実現した9GHz帯域薄膜透磁率測定装置の性能に関し,アメリカ国立標準技術研究所(NIST)およびフランス原子力研究所(CEA)と試料交換測定によるデータ検証を実施し,10%以内の誤差で測定結果(共鳴周波数)が一致するという結果を得た.これは,本装置の性能の高さを実証したものである. 次に,昨年度のシミュレーション結果に基づいて,閉磁路型スパイラルインダクタを試作した.これは,スパイラルコイルの上下に2枚の磁性薄膜を配置しその端部を接触させた構造を有している.プロセス上のポイントは,上下の磁性薄膜間の絶縁層となるSiO2にテーパエッチングを施し,30〜45°の緩やかな角度で下部磁性膜に接触させたことである.結果として,コイル幅/間隔=10/3μmと10/5μmの設計でかつコイル表面と磁性膜との距離が1μmにおいてQ=12@1GHzが得られた.1GHzにおけるQ値としてはこれまで報告された磁性薄膜インダクタの中で最も高い値であり,RF集積化磁性薄膜インダクタの実用性を実証できた. 以上の特性解析にあたり,ダブルπ型等価回路を考案し,その16個の回路定数導出法も構築した.収束計算のコスト関数としてはZ-パラメータの対数を用いることが最適である.この解析から,1-2GHzでは,磁性薄膜をインダクタに導入してもその浮遊容量に伴うLC共振周波数の低下は生じないよう設計でき,実用上必須の条件の一つが満足できることもわかった. 磁性薄膜インダクタの作製プロセスと設計法を応用し,低抵抗のCoZrNbアモルファス膜,高抵抗のCo-Zr-Oグラニュラー膜,磁気異方性が高いCo-Pd-Al-Oグラニュラー膜などを薄膜コプレーナ線路に集積化したところ,共鳴損失と渦電流損失によって4〜20GHzまで広帯域な減衰特性を示した.この帯域の減衰量はCo-Pd-Al-Oで15dBに達した一方で,1GHz以下での挿入損失は1dB以下と良好であった.インピーダンス整合を大きく乱すことなく,高周波ノイズ成分だけを低減できている事が明らかになり,IT機器内電磁干渉対策技術のロードマップから数年以内に必要とされる集積化電磁雑音対策素子のニーズに応えうるデバイスとしての可能性を明らかにできた.

  17. Development of GHz-Drive Magnetic Thin Film Inductors for Integrated Circuits

    YAMAGUCHI Masahiro, YABUKAMI Shin, ISHIYAMA Kazushi, ARAI Ken-ichi, SHIMADA Yutaka

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (A)

    Institution: Tohoku University

    2000 - 2002

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    A new GHz-band permeameter has been developed to find out the CoNbZr, FeAlO and (CoFeB)SiO_2 Thin-film materials as the possible candidates for GHz-drive inductors. A new technique on raise the ferromagnetic resonance (FMR) frequency has also been developed; Microfabricate narrow slits along the easy axis of magnetization and apply RE magnetic field along the hard axis. Then magnetic losses at 2GHz can be negligible through the optimum slit design method we established. An integrated spiral inductor with 0.1-1.0μm-thick silted CoNbZr film on the top exhibited L=8nH and Q=5 at 2GHz, Its size was 330x330μm^2. Provided that the silted CoNbZr magnetic film are installed below and on the spiral (sandwich type inductor), L=7.9nH and Q=13 has been achieved is the 200x400μm^2 size. This is worth achieving main objective of this work. An RE magnetic near field probe has been developed to analyze leakage flux from the integrated inductor to semiconductor circuit. The probe exhibited world-highest spatial resolution of 40μm at 1GHz. It is estimated that the electromagnetic interference to the integrated circuit would be negligible. An extensive application of integrated ferromagnetic film has been proposed to suppress RF in-line electromagnetic noise by means of FMR losses. Insertion loss at 1GHz was only 0.4dB while is reached 15dB as 20GHz. Thus this work has been concluded, showing a practical possibility of ferromagnetic integrated inductors as well as to pioneering a new technology field of "soft magnetic applications in the GHz range for IT." The first and second international symposium on "High Frequency Micromagnetic Devices and Materials" has been initiated by the investigators.

  18. リモート温度計測システム

    石山 和志

    Offer Organization: 日本学術振興会

    System: 科学研究費助成事業

    Category: 奨励研究(A)

    Institution: 東北大学

    2000 - 2001

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    ワイヤレス・バッテリーレスで温度計測を行うシステムの開発を目標として表記の研究を遂行した。平成13年度は、平成12年度の研究において明らかになったセンサユニットの設計指針を用いて、コアに要求される磁気特性、送信・受信回路の容量と感度、等を明確にするとともに、超小型のセンサユニットを試作し、温度計測精度ならびに最大計測距離に関する検討を行なった。これらの検討により、磁界からのワイヤレスエネルギー供給機構と、感温磁性材料を用いた温度情報のLC共振周波数への変換機構を用いて、リモート温度計測システムを構築することに成功し、プロトタイプの試作に成功した。このプロトタイプリモート温度計測システムは、0.1Kの温度精度と500mmを超える距離での遠隔動作が可能であることを明らかにした。このシステムで用いるセンサユニットとして、いくつかの方式を検討した結果、LC素子のみからなる単純な回路を用いることで、もっとも小型で高性能のセンサユニットが実現できた。このユニットは医薬品服用に用いるカプセル内に納めることができるサイズとなったため、人間がセンサユニットを服用して、体内の温度をリアルタイムモニタすることが可能となった。従来、電池を内蔵した服用型体内温度センサが宇宙飛行士用に用いられているが、親指大のサイズのセンサユニットが必要となり、本研究で開発したセンサユニットにより、画期的な小型化が実現したことになる。 以上のように作成したプロトタイプシステムの特性は、研究目標を充分に達成するものとなった。今後は現在100mmφの大きさとなっている送信・受信コイルの小型化を図るとともに、温度計測範囲を様々変えたセンサユニットを製作し、医療分野のみならず、工業分野への適用を目指した研究の進展が期待される。

  19. マイクロアクチュエータ用磁石薄膜の開発

    石山 和志

    Offer Organization: 日本学術振興会

    System: 科学研究費助成事業

    Category: 奨励研究(A)

    Institution: 東北大学

    1998 - 1999

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    磁気力を動力源としてコードレスで動く1mm程度の大きさのロボットが、特に医療応用の立場から期待されている。本研究は、この磁気を利用した微小なアクチュエータ(磁気マイクロアクチュエータ)を実現する上で必要不可欠な薄膜形状でかつ強力な磁石材料を実現することを目的に実験・検討を行った。薄膜磁石の特性向上のためには従来の磁石材料の開発とは全く異なる視点からの開発が必要であり、保磁力や最大エネルギー積よりも、角型比や異方性磁界に着目して開発すべきである。本研究では特に薄膜磁石の異方性制御を行うことによりその性能を向上させることを目標とし、材料としてSmCo系アモルファス材料を選び、検討を行った。その結果、薄膜作成時に印加する磁界により異方性を大幅に制御でき、それにより材料の角型比を高め、異方性磁界を大きくすることが可能であることを明らかにした。得られた角型比は0.95以上、異方性磁界は800kA/m、飽和磁化が1.2Tとなり、従来にない優れた材料の開発に成功した。この薄膜磁石は、1mm程度に加工すると、外部に1kA/m以上の磁界を発生させ得ることが理論計算と実験の両面から実証され、当初予定していたアクチュエータ用磁石としてのみならず、マイクロ磁気デバイスに局所磁界を印加するための微小素子としても極めて有効であることを明らかにした。加えて、様々な形状のマイクロアクチュエータに適用することを目的として、ポリイミドなどの柔軟基板上への成膜を検討し、基礎検討において行ってきたシリコン基板やガラス基板上に成膜したものと同等の特性を実現し得ることを明確にした。これらの成果により薄膜磁石材料の様々なデバイスヘの適用範囲を大きく広げる結果となった。 これらの成果は電気学会マグネティックス研究会(平成10年12月仙台)、電気学会全国大会(平成11年3月山口)、INTERMAG国際会議(平成11年5月韓国)で発表するとともに、原著論文にまとめ、公表した。

  20. Domain refinement technique for very thin silicon steel sheets

    ARAI Kenichi, KATOU Yoshinori, OHTSUKI Etsuo, BI Xisao-fang, ISHIYAMA Kazushi, YAMAGUCHI Masahiro

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Developmental Scientific Research (B)

    Institution: Tohoku University

    1994 - 1995

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    Electric energy loss at power transformers is 1.5*10^<10>kWh/year in Japan. To reduce the power loss, it is necessary to obtain a new material for the power transformer core. The purpose of this research work is to develop new grain oriented silicon steel sheets with very low loss. We did examination of effects for domain refining by grooving on the surface of the thin grain oriented silicon steel sheets, dynamic domain observation, clarifying relation between domain movement and eddy current losses, estimation of the loss of domain refined samples. We found the magneto-static energy make the domain width narrow by grooving the surface. The mechanism of generating the eddy current loss by domain wall movement were clarified. The loss value of a 32mu m thickness sample obtained by this work is extremely low as 0.21W/kg at 50Hz, 1.7T.This value is 1/5 compare with the loss of the conventional grain oriented silicon steel sheets. In conclusion, this work succeed to obtain the new material for reducing the electric power loss at the transformers. In addition, new mechanism for domain refinement are developed and the relation of domain movement and the eddy current loss were clarified.

  21. YIG単結晶薄膜を用いたマイクロインダクタの超高周波特性とその理論的解析

    山口 正洋, 石山 和志, 荒井 賢一

    Offer Organization: 日本学術振興会

    System: 科学研究費助成事業

    Category: 一般研究(B)

    Institution: 東北大学

    1993 - 1993

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    近年半導体を始め種々の電子デバイスの集積化が著しく進歩し、電子機器の小型化・軽量化が急速に実現しつつある。しかしインダクタンスを含む回路は集積化から取り残されている。このような状況に対し、最近高性能磁性薄膜の研究も大きな進展を見せ、微細加工技術を併用して小型で高周波帯域で使用可能なマイクロインダクタの開発が試みられるようになってきた。 本研究は優れた絶縁特性を有し、超高周波帯域でも高い透磁率を示すことで知られる化学量論的組成を持つYIG単結晶の薄膜を、GGG基板上に厚さ約50μm程度エピタキシャル成長させ、薄膜面上に直接銅の平面コイルを微細加工技術を駆使して構成することにより、超高周波帯でも高いインダクタンス値を示す新型のマイクロインダクタを実現するとともにその設計指針を明らかにし、更にこれに関連する測定技術、高周波解析技術等についても併せて開発することを目的とした。 その結果、まず導体幅30μm、導体厚1μm、導体間隔20μmの15往復のつづら折れコイルを膜厚20μm以上のYIGでサンドイッチした構造の磁性薄膜インダクタでは1μHに匹敵する高いインダクタンスが得られることを明らかにした。これはつづら折れコイルを用いた薄膜インダクタとしては極めて大きな値である。次いで、薄膜インダクタ中の磁束分布を簡便に表示可能なT型及びπ型等価回路を導出し、YIG単結晶膜による磁性薄膜インダクタのみならず、合金磁性薄膜インダクタについても適用可能であることを実験との対比から確認した。最後に以上の結果に基づき、YIG単結晶薄膜を用いたマイクロインダクタにおける特性の理論限界を求め、1mm角の大きさで、インダクタンスが0.5μH、100MHzにおけるQが100以になるとの注目すべき予測結果を得た。 以上のように本研究は、ほぼ所期の目的を達成することができた。

  22. Direct observation of dynamic domain behavior and core loss in ultra thin grain oriented silicon steel.

    ARAI Kenichi, ISHIYAMA Kazushi, YAMAGUCHI Masahiro

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for General Scientific Research (B)

    Institution: Tohoku University

    1991 - 1992

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    The object in this study is to observe directly the magnetic domain behavior in a toroidal core of ultra thin grain oriented silicon steel under applying rf magnetic field and to make clear the effect of domain wall number and velocity of the domain wall movement on the coarse loss. (1) We can observe the dynamic domain behavior up to 10kHz on the core surfaces and obtain the domain wall number and the velocity of domain wall movement from this observation. (2) By forming grooves perpendicular to the roll direction on the steel surface, the domain wall number in increased and the core loss is decreased.

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