2001 Fiscal Year Annual Research Report

高品位微小トンネル接合へのスピン注入

Research Project

Project/Area Number	13305001
Research Institution	Tohoku University
Principal Investigator	宮崎照宣東北大学, 大学院・工学研究科, 教授 (60101151)
Co-Investigator(Kenkyū-buntansha)	余澤中東北大学, 大学院・工学研究科, 特別研究員久保田均東北大学, 大学院・工学研究科, 助手 (30261605) 安藤康夫東北大学, 大学院・工学研究科, 助教授 (60250726) 鈴木義茂産業技術総合研究所, エレクトロニクス部門, 主任研究員
Keywords	強磁性トンネル接合 / スピン注入 / ナノサイズ / パルス磁界 / 電子線リソグラフィ / 伝導性AFM / コプレーナ / 強磁性共鳴
Research Abstract	1.ナノサイズ強磁性トンネル接合素子の作製と構造解析電子線リソグラフィを用いて最小50nm×50nmのドット状の強磁性トンネル接合を作製した.また,コンタクトホール,リード電極の作製を行わずに,伝導性AFMを用いて伝導特性を測定する新しい方法を開発した.100nm以上の接合ではS/N比が良く,多数回の磁界のスイープに対して再現性のよい磁気抵抗曲線を得た.一方,サイズの小さい接合ではループが正磁界側にシフトし,形状も左右非対称になった.これらはそれぞれ,フリー層-ピン層間の静磁気的結合,および,エッジ付近のドメイン構造の不均一性によると結論した. 2.サブナノ秒パルス磁界応答測定システムの構築強磁性トンネル接合にサブナノ秒のパルス磁界を印加し,強磁性電極の磁化反転に伴うトンネル電流の応答信号を測定する装置を製作した.測定システムはパルスジェネレータ,高速オシロスコープ,高帯域プローブにより構成した.伝送系のインピーダンス整合をとるために,接合からの電極およびパルス磁界印加用のコプレーナ線路を電子線リソグラフィを用いて加工した.これを用いて,印加磁界の立ち上がり時間が550ps,このパルス磁界によるトンネル接合の磁化反転時間6nsを観測することに成功した.また,さらに短い時間の磁化の動的運動を測定するために,極短パルスレーザを用いた磁気カー効果測定システムを設計した. 3.強磁性電極からのスピン波伝搬 Cu/FeNi/Cu/Pt積層膜の強磁性共鳴スペクトル測定した.共鳴線幅は中間Cu層厚の減少とともに増大した.スペクトルの線幅は,強磁性体のスピン緩和項と界面の構造に起因する項より表されると仮定してフィッティングを行い,Cu層厚減少に伴う線幅の増大はFeNi層で励起されたスピン波がCu層内に注入,伝搬し,対面のPt層との界面で緩和することに起因すると結論した.

Research Products

(21 results)

All Other

All Publications (21 results)

[Publications] Shigemi Mizukami: "The study on Ferromagnetic Resonance Linewidth for NM/80/NiFe/NM (NM=Cu, Ta, Pd and Pt) Films"Jpn. J. Appl. Phys.. 40. 580-585 (2001)
[Publications] Andrew C.C.Yu: "High resolution electron microscopy of Al-oxide barriers in magnetic tunnel junctions"Japanese Journal of Applied Physics. 40. 5058-5060 (2001)
[Publications] Andrew C.C.Yu: "Direct observation of domain structure and magnetization reversal of magnetic thin films using Lorentz transmission electron microscopy"Japanese Journal of Applied Physics. 40. 4891-4895 (2001)
[Publications] Andrew C.C.Yu: "Lorentz transmission electron microscopy and magnetic force microscopy characterization of NiFe/Al-oxide/Co films"Journal of Applied Physics. 91. 780-782 (2002)
[Publications] Andrew C.C.Yu: "Microstructural and magnetic characteristics of IrMn exchange-biased tunnel junction"Journal of Magnetism and Magnetic Materials. (in press).
[Publications] Andrew C.C.Yu: "Effect of Ti seed layer on the magnetization reversal process of Co/NiFe/Al-oxide/NiFe junction films"Journal of Applied Physics. (in press).
[Publications] X.F.Han: "Fabrication and magnetoelectrc properties of high-magnetoresistance tunnel junctions"J. Magn. Soc. Jpn.. 25. 707-710 (2001)
[Publications] 林将光: "強磁性トンネル接合のスピン依存局所伝導特性"日本応用磁気学会誌. 25. 759-762 (2001)
[Publications] 矢尾板和也: "プラズマ酸化法による低抵抗強磁性トンネル接合の作製"日本応用磁気学会誌. 25. 771-774 (2001)
[Publications] 大坊忠臣: "中間層にAlを用いた二重トンネル接合の磁気抵抗効果"日本応用磁気学会誌. 25. 767-770 (2001)
[Publications] T.Siripongsakul: "二重強磁性トンネル接合におけるスピン依存伝導特性"日本応用磁気学会誌. 25. 763-766 (2001)
[Publications] X, F.Han: "A self-consistent calculation and an Anisotropic Wavelength Cutoff Energy of Spin-wave Spectrum in Magnetic Tunnel Junctions"J. Mater. Sci. Technol.. 17. 197-202 (2001)
[Publications] Shigemi Mizukami: "The study on Ferromagnetic Resonance Linewidth for NM/80NiFe/NM (NM=Cu, Ta, Pd, and Pt) Films"Jpn. J. Appl. Phys.. 40. 580-585 (2001)
[Publications] Andrew C.C.Yu: "High resolution electron microscopy of Al-oxide barriers in magnetic tunnel junctions"Japanese Journal of Applied Physics. 40. 5058-5060 (2001)
[Publications] Andrew C.C.Yu: "Direct observation of domain structure and magnetization reversal of magnetic thin films using Lorentz transmission electron microscopy"Japanese Journal of Applied Physics. 40. 4891-4895 (2001)
[Publications] Andrew C.C.Yu: "Lorentz transmission electron microscopy and magnetic force microscopy characterization of NiFe/Al-oxide/Co films"Journal of Applied Physics. 91. 780-782 (2002)
[Publications] X.F.Han: "Analysis of intricsic magnetoelectric properties in spin-valve-type tunnel junctions with high magnetoresutance and low resistance"Physical Review B. 63. 224404-1-224404-7 (2001)
[Publications] H.Kubota: "Magnetoresistance and Dipole Shift of Ultrasmall Magnetic Tunnel Junctions Characterized by Conducting Atomic Force Microscopy"Jpn. J. Appl. Phys.. 41. L180-L182 (2002)
[Publications] Andrew C.C.Yu: "Microstructural and magnetic characteristics of IrMn exchange-biased tunnel junction"Journal of Magnetism and Magnetic Materials. (in press). (2002)
[Publications] Andrew C.C.Yu: "Effect of Ti seed layer on the magnetization reversal process of Co/NiFe/Al-oxide/NiFe junction films"Journal of Applied Physics. (in press). (2002)
[Publications] X.F.Han: "A self-consistent calculation of intrinsic magnetoelectric properties in magnetic tunnel junctions"J. Magn. Magn. Matter.. (in press). (2002)

2001 Fiscal Year Annual Research Report

高品位微小トンネル接合へのスピン注入

Principal Investigator

宮崎 照宣 東北大学, 大学院・工学研究科, 教授 (60101151)

Research Products

[Publications] Shigemi Mizukami: "The study on Ferromagnetic Resonance Linewidth for NM/80/NiFe/NM (NM=Cu, Ta, Pd and Pt) Films"Jpn. J. Appl. Phys.. 40. 580-585 (2001)

[Publications] Andrew C.C.Yu: "High resolution electron microscopy of Al-oxide barriers in magnetic tunnel junctions"Japanese Journal of Applied Physics. 40. 5058-5060 (2001)

[Publications] Andrew C.C.Yu: "Direct observation of domain structure and magnetization reversal of magnetic thin films using Lorentz transmission electron microscopy"Japanese Journal of Applied Physics. 40. 4891-4895 (2001)

[Publications] Andrew C.C.Yu: "Lorentz transmission electron microscopy and magnetic force microscopy characterization of NiFe/Al-oxide/Co films"Journal of Applied Physics. 91. 780-782 (2002)

[Publications] Andrew C.C.Yu: "Microstructural and magnetic characteristics of IrMn exchange-biased tunnel junction"Journal of Magnetism and Magnetic Materials. (in press).

[Publications] Andrew C.C.Yu: "Effect of Ti seed layer on the magnetization reversal process of Co/NiFe/Al-oxide/NiFe junction films"Journal of Applied Physics. (in press).

[Publications] X.F.Han: "Fabrication and magnetoelectrc properties of high-magnetoresistance tunnel junctions"J. Magn. Soc. Jpn.. 25. 707-710 (2001)

[Publications] 林将光: "強磁性トンネル接合のスピン依存局所伝導特性"日本応用磁気学会誌. 25. 759-762 (2001)

[Publications] 矢尾板和也: "プラズマ酸化法による低抵抗強磁性トンネル接合の作製"日本応用磁気学会誌. 25. 771-774 (2001)

[Publications] 大坊忠臣: "中間層にAlを用いた二重トンネル接合の磁気抵抗効果"日本応用磁気学会誌. 25. 767-770 (2001)

[Publications] T.Siripongsakul: "二重強磁性トンネル接合におけるスピン依存伝導特性"日本応用磁気学会誌. 25. 763-766 (2001)

[Publications] X, F.Han: "A self-consistent calculation and an Anisotropic Wavelength Cutoff Energy of Spin-wave Spectrum in Magnetic Tunnel Junctions"J. Mater. Sci. Technol.. 17. 197-202 (2001)

[Publications] Shigemi Mizukami: "The study on Ferromagnetic Resonance Linewidth for NM/80NiFe/NM (NM=Cu, Ta, Pd, and Pt) Films"Jpn. J. Appl. Phys.. 40. 580-585 (2001)

[Publications] Andrew C.C.Yu: "High resolution electron microscopy of Al-oxide barriers in magnetic tunnel junctions"Japanese Journal of Applied Physics. 40. 5058-5060 (2001)

[Publications] Andrew C.C.Yu: "Direct observation of domain structure and magnetization reversal of magnetic thin films using Lorentz transmission electron microscopy"Japanese Journal of Applied Physics. 40. 4891-4895 (2001)

[Publications] Andrew C.C.Yu: "Lorentz transmission electron microscopy and magnetic force microscopy characterization of NiFe/Al-oxide/Co films"Journal of Applied Physics. 91. 780-782 (2002)

[Publications] X.F.Han: "Analysis of intricsic magnetoelectric properties in spin-valve-type tunnel junctions with high magnetoresutance and low resistance"Physical Review B. 63. 224404-1-224404-7 (2001)

[Publications] H.Kubota: "Magnetoresistance and Dipole Shift of Ultrasmall Magnetic Tunnel Junctions Characterized by Conducting Atomic Force Microscopy"Jpn. J. Appl. Phys.. 41. L180-L182 (2002)

[Publications] Andrew C.C.Yu: "Microstructural and magnetic characteristics of IrMn exchange-biased tunnel junction"Journal of Magnetism and Magnetic Materials. (in press). (2002)

[Publications] Andrew C.C.Yu: "Effect of Ti seed layer on the magnetization reversal process of Co/NiFe/Al-oxide/NiFe junction films"Journal of Applied Physics. (in press). (2002)

[Publications] X.F.Han: "A self-consistent calculation of intrinsic magnetoelectric properties in magnetic tunnel junctions"J. Magn. Magn. Matter.. (in press). (2002)

宮崎照宣東北大学, 大学院・工学研究科, 教授 (60101151)