1999 Fiscal Year Annual Research Report

スピン偏極電子トンネル型大容量・高速ランダムアクセスメモリー

Research Project

Project/Area Number	09305024
Research Institution	Tokyo Institute of Technology
Principal Investigator	直江正彦東京工業大学, 工学部, 教授 (40016465)
Co-Investigator(Kenkyū-buntansha)	松下伸広東京工業大学, 工学部, 助手 (90229469) 金田久美子東京工業大学, 工学部, 助手 (10108227) 中川茂樹東京工業大学, 工学部, 助教授 (60180246)
Keywords	スピンバルブ / 巨大磁気抵抗効果 / トンネル効果 / 交換バイアス磁界 / 反強磁性層 / Si下地層 / Co / Cu多層膜
Research Abstract	本年度はトンネル型スピンバルブ素子の交換バイアス磁界印加用反強磁性FeMn層の作製条件のさらなる最適化を行うとともに、Si下地層によるCo膜の配向促進効果を利用して。Co/Cu薄膜の結晶性を高め、膜全体の抵抗率を下げるとともに、適度なアニール処理を施すことで多層膜の周期性を向上させ、多層膜内のユニット層の磁化の反強磁性的結合を促進させることにより、スピン依存散乱効果の差を大きくすることで全体の磁気抵抗効果を増大させることに成功した。主な成果は下記のとおりである。 1.FeMn層の配向制御 Si下地層厚を変化させたSi/Ni-Fe/Fe-Mn三層膜においてNi-Fe層に印加される交換結合磁界HexはSi下地層を用いない場合ではNi-Fe層がランダム配向した微結晶組織となってしまい、Fe-Mn層の(111)配向が得られず結合磁界が観測されなかったが、20ÅのSi下地層をもちることでFe-Mn層の(111)配向が著しく向上し、最大で90Oeの交換結合磁界を得ることに成功した。 2.Co/Cu多層膜のGMR特性改善効果 a-Si層をCo/Cu多層膜の下地層として用いると、他の下地層材料を用いるよりもはるかに良好な結晶配向性が誘導されることを見出した。例えば、Ta下地層もCo(111)面の結晶配向を促進する特性を有しており、Co単層膜においてはSi下地層よりも良好な結果が得られるが、Co/Cu多層膜の下地層として使った場合には、Si地層を使った場合の6分の1程度のピーク強度となる。Co/Cuの層数が大きくなるほどピーク強度に大きな差が現れる傾向があった。 3.トンネル型スピンバルブ素子の作成 Siスパッタ層を窒化して絶縁層としてトンネル型スピンバルブ素子の作製を試みたところ、トンネル電流による非線形電流電圧特性を確認することに成功した。FeMn反強磁性層による交換バイアス磁界の印加にも成功した。

Research Products
(24 results)

All Other

All Publications (24 results)

[Publications] Shigeki Nakagawa,Kazuhisa Takayama,Atsushi Sato and Masahiko Naoe: "Study of Magnetization Reversal Mechanism of Very Thin Film with Perpendicular Magnetic Anisotropy by Means of the Anomalous Hall Effect"J. Appl. Phys.. 85,[8]. 4592-4594 (1999)
[Publications] Shigeki Nakagawa,Koichi Nishimura,Yutaka Shimizu and Masahiko Naoe: "Ultra-Thin Si Buffer Laycrs to Improve the Exchange Bias Between Ni-Fe and Fe-Mn Layers"J. Appl. Phys.. 85,[8]. 4934-4936 (1999)
[Publications] Jie Feng,Nobuhiro Matsushita,Ko Watanabe,Shigeki Nakagawa and Masahiko Naoe: "Al Substituted Ba Ferrite Films with High Coercivity and Excellent Squareness for Low Noise Perpendicular Recording Layer"J. Appl. Phys.. 85,[8]. 6139-6141 (1999)
[Publications] Shigeki Nakagawa,Masaru Hatakeyama,Kazuhisa Takayama and Masahiko Naoe: "Study of Initial Growth Region of Co83Cr17 in Co83Cr17/Co67Cr33/Cr Trilayered Films for Longitudinal Recording Media"J. Magn. Magn. Mater.. 193. 63-67 (1999)
[Publications] Nobuhiro Matsushita,Makoto Ichinose,Shigeki Nakagawa and Masahiko Naoe: "Co-Zn Ferrite Films Prepared by Faching Targets Sputtering System for Longitudinal Recording Layer"J. Magn. Magn. Mater.. 193. 68-70 (1999)
[Publications] Kohki Noda,Takashi Kawanabe and Masahiko Naoe: "Recording Characteristics and Magnetic Grains of Rigid Disks Using Silicon Substrate Deposited by Facing Targets Sputtering"J. Magn. Magn. Mater.. 193. 71-74 (1999)
[Publications] Akimitsu Morisako,Mitsunori Matsumoto and Masahiko Naoe: "Properties of c-axis Oriented Ba-Ferrite Sputtered Films"J. Magn. Magn. Mater.. 193. 110-113 (1999)
[Publications] Sadao Kadokura and Masahiko Naoe: "Perpendicular Co-Cr Thin Films Using a new Sputtering Plasma Generating Apparatus"J. Magn. Magn. Mater.. 193. 114-116 (1999)
[Publications] Nobuhiro Matsushita,Jie Feng,Tomoyosi Siosawa,Shigeki Nakagawa and Masahiko Naoe: "Relationship between Coersivity and Deposition Conditions of Ba Ferrite Films Prepared by Facing Targets Sputtering Apparatus"J. Magn. Magn. Mater.. 193. 121-123 (1999)
[Publications] Jie Feng,Nobuhiro Matsushita,Tomohiro Murakoso,Shigeki Nakagawa and Masahiko Naoe: "Effect of Al Substitution for Fe in Ba Ferrite Thin Films"J. Magn. Magn. Mater.. 193. 152-154 (1999)
[Publications] Masahiko Naoe and Sadao Kadokura: "Preparation of Co-Cr-Ta Films with Nano-Size Magnetic Domains for 1000 kfci Media"J. Magn. Magn. Mater.. 193. 185-191 (1999)
[Publications] Kiyoshi Kuga,Yoshiro Yoneda,Junji Numazawa and Masahiko Naoe: "Large Output and High Density Recording Tape with Perpendicular Magnetic Co-Cr-Ta Film for VCR"
[Publications] Shigeki Nakagawa,Kazuhisa Takayama,Atsushi Sato and Masahiko Naoe: "Study of Perpendicular Magnetic Anisotropy in Ultra-Thin Co-Cr Films Evaluated by Anomalous Hall Effect"IEEE Trans. Magn.. 35巻5号. 2739-2741 (1999)
[Publications] Atsushi Sato,Masaru Hatakeyama,Shigeki Nakagawa and Masahiko Naoe: "Deposition of Paramagnetic Co4Cr2 Seed Layer for Ferromagnetic Co5Cr1 Recording Layer in High Density Perpendicular Media"IEEE Trans. Magn.. 35巻5号. 2742-2744 (1999)
[Publications] Kiyoshi Kuga,Yoshiro Yoneda,Junji Numazawa and Masahiko Naoe: "Magnetic Properties and Recording Characteristics of Co-Cr-Ta-Mo Perpendicular Recording Media"IEEE Trans. Magn.. 35巻5号. 2745-2747 (1999)
[Publications] Tatsuo Namikawa,Kumiko Kaneta,Nobuhiro Matsushita,Shigeki Nakagawa and Masahiko Naoe: "Annealing Effect of Magnetic Characteristics of (La, Sr) MnO3 Sputtered Films"IEEE Trans. Magn.. 35巻5号. 2850-2852 (1999)
[Publications] Shigeki Nakagawa,Koichi Nishimura,Yutaka Shimizu and Masahiko Naoe: "Improvement of Crystallinity and Exchange Bias Field in Reverse Type Ni-Fe/FeMn Bilayers Using Si/Ni-Fe Composite Type of Underlayers"IEEE Trans. Magn.. 35巻5号. 2970-2972 (1999)
[Publications] Masahiko Naoe,Nobuhiro Matsushita,Kou Watanabe,Makoto Ichinose and Shigeki Nakagawa: "Deposition of c-axis Oriented BaM Ferrite Layers with Low Surface Roughness on Textured Undelayers"IEEE Trans. Magn.. 35巻5号. 3016-3018 (1999)
[Publications] Shigeki Nakagawa,Kazunari Hiraide and Masahiko Naoe: "Development of High Density Perpendicular Magnetic Recording System Using a Probe Head of Sharpened Optical Fiber"IEEE Trans. Magn.. 35巻5号. 3130-3132 (1999)
[Publications] Susumu Abe,Akira Matsushita,Kiyoshi Negishi,Yasuhisa Baba and Masahiko Noae: "Generation of large Barkhausen Jump with Bilayered Thin Film"IEEE Trans. Magn.. 35巻5号. 3634-3636 (1999)
[Publications] 佐藤厚、高山和久、酒巻直人、中川茂樹、直江正彦: "Co-Cr垂直磁化膜の異常ホール効果測定と磁気特性の評価"日本応用磁気学会論文誌. 23巻[4-2]. 1181-1185 (1999)
[Publications] 一瀬誠、村社智宏、松下伸広、中川茂樹、直江正彦: "Pt および Au下地層を使用したBaフェライト薄膜の作製"日本応用磁気学会論文誌. 23巻[4-2]. 1205-1208 (1999)
[Publications] 馮潔、渡部康、松下伸広、中川茂樹、直江正彦: "Al置換BaMフェライト薄膜の磁気特性"日本応用磁気学会論文誌. 23巻[4-2]. 1213-1216 (1999)
[Publications] 中川茂樹、佐藤厚、佐々木一郎、直江正彦: "Pt 下地層上の超薄 Co-Cr 合金垂直磁化膜の特性改善"日本応用磁気学会論文誌. 23巻[S2]. 59-62 (1999)

1999 Fiscal Year Annual Research Report

スピン偏極電子トンネル型大容量・高速ランダムアクセスメモリー

Principal Investigator

直江 正彦 東京工業大学, 工学部, 教授 (40016465)

Research Products

[Publications] Shigeki Nakagawa,Kazuhisa Takayama,Atsushi Sato and Masahiko Naoe: "Study of Magnetization Reversal Mechanism of Very Thin Film with Perpendicular Magnetic Anisotropy by Means of the Anomalous Hall Effect"J. Appl. Phys.. 85,[8]. 4592-4594 (1999)

[Publications] Shigeki Nakagawa,Koichi Nishimura,Yutaka Shimizu and Masahiko Naoe: "Ultra-Thin Si Buffer Laycrs to Improve the Exchange Bias Between Ni-Fe and Fe-Mn Layers"J. Appl. Phys.. 85,[8]. 4934-4936 (1999)

[Publications] Jie Feng,Nobuhiro Matsushita,Ko Watanabe,Shigeki Nakagawa and Masahiko Naoe: "Al Substituted Ba Ferrite Films with High Coercivity and Excellent Squareness for Low Noise Perpendicular Recording Layer"J. Appl. Phys.. 85,[8]. 6139-6141 (1999)

[Publications] Shigeki Nakagawa,Masaru Hatakeyama,Kazuhisa Takayama and Masahiko Naoe: "Study of Initial Growth Region of Co83Cr17 in Co83Cr17/Co67Cr33/Cr Trilayered Films for Longitudinal Recording Media"J. Magn. Magn. Mater.. 193. 63-67 (1999)

[Publications] Nobuhiro Matsushita,Makoto Ichinose,Shigeki Nakagawa and Masahiko Naoe: "Co-Zn Ferrite Films Prepared by Faching Targets Sputtering System for Longitudinal Recording Layer"J. Magn. Magn. Mater.. 193. 68-70 (1999)

[Publications] Kohki Noda,Takashi Kawanabe and Masahiko Naoe: "Recording Characteristics and Magnetic Grains of Rigid Disks Using Silicon Substrate Deposited by Facing Targets Sputtering"J. Magn. Magn. Mater.. 193. 71-74 (1999)

[Publications] Akimitsu Morisako,Mitsunori Matsumoto and Masahiko Naoe: "Properties of c-axis Oriented Ba-Ferrite Sputtered Films"J. Magn. Magn. Mater.. 193. 110-113 (1999)

[Publications] Sadao Kadokura and Masahiko Naoe: "Perpendicular Co-Cr Thin Films Using a new Sputtering Plasma Generating Apparatus"J. Magn. Magn. Mater.. 193. 114-116 (1999)

[Publications] Nobuhiro Matsushita,Jie Feng,Tomoyosi Siosawa,Shigeki Nakagawa and Masahiko Naoe: "Relationship between Coersivity and Deposition Conditions of Ba Ferrite Films Prepared by Facing Targets Sputtering Apparatus"J. Magn. Magn. Mater.. 193. 121-123 (1999)

[Publications] Jie Feng,Nobuhiro Matsushita,Tomohiro Murakoso,Shigeki Nakagawa and Masahiko Naoe: "Effect of Al Substitution for Fe in Ba Ferrite Thin Films"J. Magn. Magn. Mater.. 193. 152-154 (1999)

[Publications] Masahiko Naoe and Sadao Kadokura: "Preparation of Co-Cr-Ta Films with Nano-Size Magnetic Domains for 1000 kfci Media"J. Magn. Magn. Mater.. 193. 185-191 (1999)

[Publications] Kiyoshi Kuga,Yoshiro Yoneda,Junji Numazawa and Masahiko Naoe: "Large Output and High Density Recording Tape with Perpendicular Magnetic Co-Cr-Ta Film for VCR"

[Publications] Shigeki Nakagawa,Kazuhisa Takayama,Atsushi Sato and Masahiko Naoe: "Study of Perpendicular Magnetic Anisotropy in Ultra-Thin Co-Cr Films Evaluated by Anomalous Hall Effect"IEEE Trans. Magn.. 35巻5号. 2739-2741 (1999)

[Publications] Atsushi Sato,Masaru Hatakeyama,Shigeki Nakagawa and Masahiko Naoe: "Deposition of Paramagnetic Co4Cr2 Seed Layer for Ferromagnetic Co5Cr1 Recording Layer in High Density Perpendicular Media"IEEE Trans. Magn.. 35巻5号. 2742-2744 (1999)

[Publications] Kiyoshi Kuga,Yoshiro Yoneda,Junji Numazawa and Masahiko Naoe: "Magnetic Properties and Recording Characteristics of Co-Cr-Ta-Mo Perpendicular Recording Media"IEEE Trans. Magn.. 35巻5号. 2745-2747 (1999)

[Publications] Tatsuo Namikawa,Kumiko Kaneta,Nobuhiro Matsushita,Shigeki Nakagawa and Masahiko Naoe: "Annealing Effect of Magnetic Characteristics of (La, Sr) MnO3 Sputtered Films"IEEE Trans. Magn.. 35巻5号. 2850-2852 (1999)

[Publications] Shigeki Nakagawa,Koichi Nishimura,Yutaka Shimizu and Masahiko Naoe: "Improvement of Crystallinity and Exchange Bias Field in Reverse Type Ni-Fe/FeMn Bilayers Using Si/Ni-Fe Composite Type of Underlayers"IEEE Trans. Magn.. 35巻5号. 2970-2972 (1999)

[Publications] Masahiko Naoe,Nobuhiro Matsushita,Kou Watanabe,Makoto Ichinose and Shigeki Nakagawa: "Deposition of c-axis Oriented BaM Ferrite Layers with Low Surface Roughness on Textured Undelayers"IEEE Trans. Magn.. 35巻5号. 3016-3018 (1999)

[Publications] Shigeki Nakagawa,Kazunari Hiraide and Masahiko Naoe: "Development of High Density Perpendicular Magnetic Recording System Using a Probe Head of Sharpened Optical Fiber"IEEE Trans. Magn.. 35巻5号. 3130-3132 (1999)

[Publications] Susumu Abe,Akira Matsushita,Kiyoshi Negishi,Yasuhisa Baba and Masahiko Noae: "Generation of large Barkhausen Jump with Bilayered Thin Film"IEEE Trans. Magn.. 35巻5号. 3634-3636 (1999)

[Publications] 佐藤 厚、高山 和久、酒巻 直人、中川 茂樹、直江正彦: "Co-Cr垂直磁化膜の異常ホール効果測定と磁気特性の評価"日本応用磁気学会論文誌. 23巻[4-2]. 1181-1185 (1999)

[Publications] 一瀬 誠、村社智宏、松下伸広、中川茂樹、直江正彦: "Pt および Au下地層を使用したBaフェライト薄膜の作製"日本応用磁気学会論文誌. 23巻[4-2]. 1205-1208 (1999)

[Publications] 馮 潔、渡部 康、松下伸広、中川茂樹、直江正彦: "Al置換BaMフェライト薄膜の磁気特性"日本応用磁気学会論文誌. 23巻[4-2]. 1213-1216 (1999)

[Publications] 中川茂樹、佐藤 厚、佐々木一郎、直江正彦: "Pt 下地層上の超薄 Co-Cr 合金垂直磁化膜の特性改善"日本応用磁気学会論文誌. 23巻[S2]. 59-62 (1999)

直江正彦東京工業大学, 工学部, 教授 (40016465)

[Publications] 佐藤厚、高山和久、酒巻直人、中川茂樹、直江正彦: "Co-Cr垂直磁化膜の異常ホール効果測定と磁気特性の評価"日本応用磁気学会論文誌. 23巻[4-2]. 1181-1185 (1999)

[Publications] 一瀬誠、村社智宏、松下伸広、中川茂樹、直江正彦: "Pt および Au下地層を使用したBaフェライト薄膜の作製"日本応用磁気学会論文誌. 23巻[4-2]. 1205-1208 (1999)

[Publications] 馮潔、渡部康、松下伸広、中川茂樹、直江正彦: "Al置換BaMフェライト薄膜の磁気特性"日本応用磁気学会論文誌. 23巻[4-2]. 1213-1216 (1999)

[Publications] 中川茂樹、佐藤厚、佐々木一郎、直江正彦: "Pt 下地層上の超薄 Co-Cr 合金垂直磁化膜の特性改善"日本応用磁気学会論文誌. 23巻[S2]. 59-62 (1999)