| Project/Area Number |
12555250
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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 | 展開研究 |
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| Research Field |
無機工業化学
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| Research Institution | Hokkaido University |
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Principal Investigator |
KIKKAWA Shinichi Hokkaido Univ., Grad. School of Eng., Prof., 大学院・工学研究科, 教授 (10127219)
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| Co-Investigator(Kenkyū-buntansha) |
TAKAHASHI Masao Osaka Univ., Inst. Sci. Ind. Res., Assoc. Prof., 産業科学研究所, 助教授 (00188054)
SAEKI Isao Muroran Inst. Tech., Dept. of Master. Sci. and Eng., Assoc. Prof., 材料物性工学科, 助教授 (50235090)
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| Project Period (FY) |
2000 – 2002
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| Project Status |
Completed (Fiscal Year 2002)
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| Budget Amount *help |
¥12,700,000 (Direct Cost: ¥12,700,000)
Fiscal Year 2002: ¥1,900,000 (Direct Cost: ¥1,900,000)
Fiscal Year 2001: ¥1,700,000 (Direct Cost: ¥1,700,000)
Fiscal Year 2000: ¥9,100,000 (Direct Cost: ¥9,100,000)
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| Keywords | giant magnetization / iron nitride / fine crystal / thin film / low temperature nitridation / giant magneto resistance / 高周波スパッタ |
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| Research Abstract |
(1) Well crystallized Fe__<16>N__2 was obtained in high purity by low temperature nitridation of α-Fe fine powder in 100nm crystallite size at 130℃ for 100hour. The product had a saturation magnetization of 225emu/g at room temperature. The value was 16% larger than that for α-Fe starting powder. There were three kinds of ferromagnetic components in its Mossbauer spectrum. Their average magnetic moment was 2.52μB. Giant magnetization of 270emu/g can be calculated by assuming that 19% of superparamagnetic impurity will turn to be ferromagnetic.
(2) No iron nitride was detected after a nitridation below 220℃ of the sputter deposited α-Fe thin film. The film was deposited for 60mintute and its film thickness was 360nm. Formation temperature of iron nitrides such as Fe_3N became lower in the thinner α-Fe films deposited in shorter duration. Α-Fe crystal lattice expanded and its crystallite size became smaller in the thinner films. Scanning probe microscope showed that the α-Fe thinner film was composed with a linkage of smaller α-Fe particles. These three factors may affect the experimental result that the thinner films were nitrided in lower temperature.
(3) Ferromagnetic thin films for spin tunnel junction using A1N as an insulating layer were sputter deposited from either 75Fe-25Ni composite or alloy targets. Α-(Fe, Ni) with 30〜40at%Ni was observed in the former film and γ-(Fe, Ni) with 40〜55at%Ni was in the latter film, respectively. The former showed a large saturation magnetization of around 200emu/g. There was an enough difference in magnetic coercivity between the films deposited at 100W of rf-power(55Oe) and at 250W(30Oe).
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