1997 Fiscal Year Final Research Report Summary
Fundamental Study on magnetic-granular films with fine structures
| Project/Area Number |
08455142
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| Research Category |
Grant-in-Aid for Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Electronic materials/Electric materials
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| Research Institution | Nagoya University |
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Principal Investigator |
TANJI Takayoshi Nagoya university, Center for Integrated Research in Science and Engineering Associate Professor, 理工科学総合研究センター, 助教授 (90125609)
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| Co-Investigator(Kenkyū-buntansha) |
MUROOKA Yoshie Nagoya university, School of Engineering Research Associate, 工学研究科, 助手 (40273263)
TANAKA Sigeyasu Nagoya university, School of Engineering Research Associate, 工学研究科, 助手 (70217032)
KIMURA Keiko Nagoya university, Center for Integrated Research in Science and Engineering Res, 理工科学総合研究センター, 助手 (60262862)
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| Project Period (FY) |
1996 – 1997
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| Keywords | fine magnetic structure / granular film / Lorentz microscopy / electron beam annealing |
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| Research Abstract |
The theme of this research is to make fine structures of magnetic granular thin films. Magnetic granular films have been remarked as one of new magnetic substances. Specifically, it has been aimed to produce fine magnetic-granular areas less than a few tens nanometers in an amorphous thin film. No method to investigate the magnetic state in such small region bad been confirmed, so far. Therefore, first of all, we had to realized the observation of the magnetism of fine particles less than 10 nm. In order to make a pattern of granular area, the original matrix is required to be amorphous or a poly-crystal of ultra fine grains less than 1 nm in diameter.
Following results have been obtained in this project ;
i) We have found the condition to make an amorphous film of Fe_8Mo_2 using a DC magnetron sputtering method.
ii) By Lorentz electron microscopy using a transmission electron microscope instrument equipped with a field emission electron gun and a magnetically shielded electron lens, we observed successfully the magnetic states of fine particles less than 10 nm which have single magnetic domains in the case of Fe particles embedded in a MgO single crystal and Fe particles precipitated in a Fe_8Mo_2 amorphous film.
iii) We have realized to precipitate partially fine particles in the Fe_8Mo_2 amorphous film by 200 keV electron irradiation with an assist of a heating stage for transmission electron microscopy. A character "N" of granular area wi th the width less than 100 nm was drown in the amorphous film. Some particles in such area was found to have self magnetization by Lorentz microscopy, and small area x-ray analysis confirmed that the atomic concentration of Fe in such particles is la rger than 80% on the matrix.
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