1997 Fiscal Year Annual Research Report

巨大磁気抵抗効果を用いた電気機械変換薄膜素子の開発

Research Project

Project/Area Number	08455165
Research Institution	HIROSHIMA UNIVERSITY
Principal Investigator	本多茂男広島大学, 工学部, 助教授 (00034405)
Co-Investigator(Kenkyū-buntansha)	縄手雅彦島根大学, 地球共同研究センター, 助教授 (10198400)
Keywords	反強磁性MnPt膜 / FeCoフリー層 / 軟磁性Fe-SiO_2 / スピンバルブ膜 / 交換磁場 / 比抵抗 / ブロッキング温度 / 熱的安定性
Research Abstract	電気機械変換薄膜素子の基盤となるスピンバルプ膜の開発・研究を行い,以下の成果を得た. 1)MnPt/FeCo積層膜において,大きな交換磁場(H_<ex>)を得た. i)glass/Cu(80Å)/Fe_<19>Co_<81>(100Å)/MnPt(100Å)積層膜において,Mn組成が51at.%の積層膜を熱処理したとき,最大のH_<ex>がら得られた.このとき,Mn_<51>Pt_<49>の比抵抗は約265μΩ・cm,ブロッキング温度は300〜370℃であった. ii)Fe_<19>Co_<81>(100Å)/Mn_<51>Pt_<49>(300Å)積層膜を熱処理したとき,230℃からCuAu-I型fct構造に規則化することによりH_<ex>は増加し始め,320℃で最大値286〜356 Oeを示す.しかし,350℃以上の熱処理でFeCo層とMnPt層の界面でのミキシングが起こり,H_<ex>は減少し始める.このミキシング過程を実際にRBSにより確認した.このミキシングを防ぐためにFeとCoの両方に対して完全非固溶であるAgをFeCo層とMnPt層との間に挟むことにより,30℃だけ耐熱性を改善することができた. 2.耐熱性に優れた高感度スピンバルブ膜FeCo/Cu/FeCo/MnPtの作製した. i)RFマグネトロンスパッタ法によりガラス基板上に堆積したFeCo(50Å)/Cu(t_<Cu>)/FeCo(35Å)/MnPt(300Å)膜の熱処理効果:290℃で熱処理したとき,t_<Cu>=30Åで最大MR比6.2%が得られた.t_<Cu>が35Å以下では幾分熱的安定性に欠けるが,40Å以上では320℃まで安定で,この温度での熱処理によりMR比は寧ろ増加する. ii)磁場感度の増大:軟磁性Fe-SiO_2グラニュラー膜を,フリーFeCo層の上に堆積することにより,フリー層の保磁力を低減し,感度の向上を図ることに成功した.

Research Products
(14 results)

All Other

All Publications (14 results)

[Publications] 本多茂男: "Magnetic structure and perpendicular magnetic anisotropy of rare-earth(Nd,Pr,Gd)/Fe multilayers" Journal of Applied Physics. 79. 365-372 (1996)
[Publications] 縄手雅彦: "Pseudo-granular giant magnetoresistance in NiFe/Ag multilayers" Journal of Magnetism and Magnetic Materials. 156. 383-384 (1996)
[Publications] 坂本勲: "CEMS study of the magnetic properties of Au/Fe multilayers" Proceeding of ICAME-95. 635-638 (1996)
[Publications] 本多茂男: "Giant magnetoresistance of perpendicular magnetic Co/Au multilayers" Journal of Applied Physics. 80. 5175-5182 (1996)
[Publications] 本多茂男: "Tunneling giant magnetoresistance in Fe-SiO_2 multilayered and alloyed films" Journal of Magnetism and Magnetic Materials. 165. 153-156 (1996)
[Publications] 坂本勲: "CEMS study of Au/Fe multilayers in annealing process" Journal of Magnetism and Magnetic Materials. 165. 208-211 (1996)
[Publications] 本多茂男: "Size effect on giant magnetoresistance of Co-Ag films" Journal of Magnetism and Magnetic Materials. 165. 326-329 (1996)
[Publications] 本多茂男: "Giant magnetoresistance and superparamagnetic grains in Co-Ag granular films" Journal of Applied Physics. 82. 764-771 (1997)
[Publications] 本多茂男: "Magnetic properties and giant magnetoresistance of Fe/Au multilayers" Journal of Applied Physics. 82. 4428-4434 (1997)
[Publications] 本多茂男: "Tunneling giant magnetoresistance in heterogeneous Fe-SiO_2 granular films" Physical Revew. B56. 14566-14573 (1997)
[Publications] 本多茂男: "Perpendicular magnetic anisotropy and giant magnetoresistance of Co-Au alloyed films" Proceeding of 4th Perpendicular Magn.Reco.Conf.363-366 (1997)
[Publications] 坂本勲: "Magnetic and structural changes of Au/Fe multilayers induced by Ar ion irradiation and thermal annealing" Proceeding of IUMRS International Conference. (印刷中).
[Publications] 本多茂男: "Tunneling magnetoresistance in FeCo-SiO_2 granular films" Proceeding of IUMRS International Conference. (印刷中).
[Publications] 本多茂男: "Giant magnetoresistance of pseudo-granular Co-Au and Co-Ag films" Proceeding of IUMRS International Conference. (印刷中).

1997 Fiscal Year Annual Research Report

巨大磁気抵抗効果を用いた電気機械変換薄膜素子の開発

Principal Investigator

本多 茂男 広島大学, 工学部, 助教授 (00034405)

Research Products

[Publications] 本多茂男: "Magnetic structure and perpendicular magnetic anisotropy of rare-earth(Nd,Pr,Gd)/Fe multilayers" Journal of Applied Physics. 79. 365-372 (1996)

[Publications] 縄手雅彦: "Pseudo-granular giant magnetoresistance in NiFe/Ag multilayers" Journal of Magnetism and Magnetic Materials. 156. 383-384 (1996)

[Publications] 坂本勲: "CEMS study of the magnetic properties of Au/Fe multilayers" Proceeding of ICAME-95. 635-638 (1996)

[Publications] 本多茂男: "Giant magnetoresistance of perpendicular magnetic Co/Au multilayers" Journal of Applied Physics. 80. 5175-5182 (1996)

[Publications] 本多茂男: "Tunneling giant magnetoresistance in Fe-SiO_2 multilayered and alloyed films" Journal of Magnetism and Magnetic Materials. 165. 153-156 (1996)

[Publications] 坂本勲: "CEMS study of Au/Fe multilayers in annealing process" Journal of Magnetism and Magnetic Materials. 165. 208-211 (1996)

[Publications] 本多茂男: "Size effect on giant magnetoresistance of Co-Ag films" Journal of Magnetism and Magnetic Materials. 165. 326-329 (1996)

[Publications] 本多茂男: "Giant magnetoresistance and superparamagnetic grains in Co-Ag granular films" Journal of Applied Physics. 82. 764-771 (1997)

[Publications] 本多茂男: "Magnetic properties and giant magnetoresistance of Fe/Au multilayers" Journal of Applied Physics. 82. 4428-4434 (1997)

[Publications] 本多茂男: "Tunneling giant magnetoresistance in heterogeneous Fe-SiO_2 granular films" Physical Revew. B56. 14566-14573 (1997)

[Publications] 本多茂男: "Perpendicular magnetic anisotropy and giant magnetoresistance of Co-Au alloyed films" Proceeding of 4th Perpendicular Magn.Reco.Conf.363-366 (1997)

[Publications] 坂本勲: "Magnetic and structural changes of Au/Fe multilayers induced by Ar ion irradiation and thermal annealing" Proceeding of IUMRS International Conference. (印刷中).

[Publications] 本多茂男: "Tunneling magnetoresistance in FeCo-SiO_2 granular films" Proceeding of IUMRS International Conference. (印刷中).

[Publications] 本多茂男: "Giant magnetoresistance of pseudo-granular Co-Au and Co-Ag films" Proceeding of IUMRS International Conference. (印刷中).

本多茂男広島大学, 工学部, 助教授 (00034405)