1994 年度実績報告書

巨大磁気抵抗効果を用いたスピンバルブ型スタティックメモリー素子の開発

研究課題

研究課題/領域番号	06452213
研究機関	東京工業大学
研究代表者	直江正彦東京工業大学, 工学部, 教授 (40016465)
研究分担者	松下伸広東京工業大学, 工学部, 助手 (90229469) 中川茂樹東京工業大学, 工学部, 助手 (60180246)
キーワード	スピンバルブ / 巨大磁気抵抗効果 / 多層膜 / メモリー素子 / Ni-Fe / Cu多層膜 / イオンビームスパッタ
研究概要	通常の磁気記録のような接触走行部を持たずに大容量の記録・再生が可能である「スピンバルブ型磁気メモリー素子」についての研究として本年度は「巨大磁気抵抗効果多層膜の作製およびスピンバルブ素子の試作」を行った。巨大磁気抵抗効果を発現するNi-Fe/Cu多層膜をイオンビームスパッタ装置で作製し、その磁気抵抗変化率(MR比)、磁界感度を増し、飽和磁界を減少するための作製条件や下地配向度の制御などを行った。この結果、より大きな磁界感度を得るためにはNi-Fe/Cu多層膜中の結晶配向を(100)配向にする必要があり、このためにFeバッファー層を(100)配向にする必要があることを見い出した。(100)配向膜を得るためにはイオンビームスパッタ法のような制御範囲の広いスパッタ法を適用することが望ましい。また、多層膜形成時に成膜面に百数十V程度のエネルギーのイオンを照射することにより、さらに(100)配向が促進出来ることを見い出した。よって本年度は、Ni-Fe本来の軟磁気特性を生かした巨大磁気抵抗多層膜の特性改善のための指針を得ることができたといえる。一方、スピンバルブ素子として、Ni-Fe/Cu/Ni-Feサンドイッチ膜に反強磁性Fe-Mn層による交換バイアスを与える研究を行った。Fe-Mn層によって磁界バイアスを与えるためには、Fe-Mn(111)配向面上に磁性層を接合しなければならないことを見い出し、あらかじめ(111)配向した極薄のNi-Fe層あるいはCu層を堆積し、そのうえにFe-Mn層を作製し(111)配向を助長したスピンバルブ素子において良好な磁界バイアス効果が観測された。また、比較的良好なMR特性も観測している。スピンバルブ素子の集積デバイス化については若干の遅れがあるが、これはリソグラフィー技術とエッチング技術についての最適化が遅れているためであり、次年度以降に精力的に押し進める予定である。

研究成果

(18件)

すべてその他

すべて文献書誌 (18件)

[文献書誌] Nobuhiro MATSUSHITA: "Preparation of Co-Zn ferrite films at low substrate temperature by plasma-free DC sputtering for magnetic recording media" J. Appl. Phys.75[10]. 5975-5977 (1994)
[文献書誌] Akimitsu MORISAKO: "Low-Temperature deposition of hexagonal ferrite films by sputtering" J. Appl. Phys.75[10]. 5969-5971 (1994)
[文献書誌] Kiyoshi KUGA: "Improvement of anisotropy of perpendicular magnetic recoding tape by Ta addition and Kr sputtering gas" J. Appl. Phys.75[10]. 5987-5987 (1994)
[文献書誌] Kibong SONG: "Magnetic and optical characteristics of bilayered films composed of Tb-Fe-Co layer with overlayers of Co-Cr, Ni-Fe, Ta and C" J. Appl. Phys.75[10]. 6357-6359 (1994)
[文献書誌] Takakazu TAKAHASHI: "Structural and magretic characteristics of Co_<31>Cr_<19>/Al multilayers deposited by plasma-free sputtring with Kr gas" J. Appl. Phys.75[10]. 6509-6509 (1994)
[文献書誌] Masahiko NAOE: "Preparation of Ni-Fe/Cu multilayers with low coercivity and GMR effect by ion beam sputtering." J. Appl. Phys.75[10]. 6525-6527 (1994)
[文献書誌] Shigeki NAKAGAWA: "Preparation and magnetic properties of Mn_4N films by reactive facing targets sputtering" J. Appl. Phys.75[10]. 6568-6570 (1994)
[文献書誌] Nobuhiro MATSUSHITA: "Preparation and magnetic properties of BaM films with excellent crystallinity by Xe sputtering" J. Appl. Phys.75[10]. 7131-7133 (1994)
[文献書誌] Shigeki NAKAGAWA: "Methods to control internal stress in Co-Cr sputtered films on polymer tape for curl-free recording tape" J. Magn. Magn. Mater.134. 354-361 (1994)
[文献書誌] Masahiko NAOE: "Physics and technolgy of sputtering for depositing magnetic films" J. Magn. Magn. Mater.134. 395-402 (1994)
[文献書誌] Akimitsu MORISAKO: "The effects of Pb addition on crystal structure and magnetic properties of Ba-ferrite sputtered films" J. of Magn. Soc. of Jpn.18[S2]. 69-72 (1994)
[文献書誌] Shigeki NAKAGAWA: "Dual track complimentary type of thin film recording heads for perpendicular magnetic recording" J. of Magn. Soc. of Jpn.18[S2]. 213-216 (1994)
[文献書誌] Masahiko NAOE: "Voidless grainboundary growth process of Co-Cr thin films" J. of Magn. Soc. of Jpn.18[S2]. 331-334 (1994)
[文献書誌] Yasuyoshi MIYAMOTO: "Enhancement in MR field sensitivity of [Ni_<81>Fe_<19>/Cu] Multilayers by control of crysiallite orientation in Fe buffer layer" J. of Magn. Soc. of Jpn.18[S2]. 409-412 (1994)
[文献書誌] Kenji NOMA: "Preparation and recording characteristics of rigid disks using Co-Zn ferrite sputtered films for high density magnetic recording with perpendicular anisotropy" J. of Magn. Soc. of Jpn.18[S2]. 447-450 (1994)
[文献書誌] Masahiko NAOE: "Control of microstructure of Co-Cr thin films by adjusting sputtering condition" J. of Magn. Soc. of Jpn.18[S2]. 479-484 (1994)
[文献書誌] Nobuhiro MATSUSHITA: "Structure and magnetic properties of a hexagonal type ferrite thin films prepared by facing targets sputtering" Proc. the first Magneto-Electronics Int. Symp.11-14 (1994)
[文献書誌] Shigeki NAKAGAWA: "Strict control of C-axis orientation and magnetic anisotropy in Co-Cr thin films for perpendicular magnetic recording media" Proc. the first Magneto-Electronics Int. Symp.15-18 (1994)

1994 年度 実績報告書

巨大磁気抵抗効果を用いたスピンバルブ型スタティックメモリー素子の開発

研究代表者

直江 正彦 東京工業大学, 工学部, 教授 (40016465)

研究成果

[文献書誌] Nobuhiro MATSUSHITA: "Preparation of Co-Zn ferrite films at low substrate temperature by plasma-free DC sputtering for magnetic recording media" J. Appl. Phys.75[10]. 5975-5977 (1994)

[文献書誌] Akimitsu MORISAKO: "Low-Temperature deposition of hexagonal ferrite films by sputtering" J. Appl. Phys.75[10]. 5969-5971 (1994)

[文献書誌] Kiyoshi KUGA: "Improvement of anisotropy of perpendicular magnetic recoding tape by Ta addition and Kr sputtering gas" J. Appl. Phys.75[10]. 5987-5987 (1994)

[文献書誌] Kibong SONG: "Magnetic and optical characteristics of bilayered films composed of Tb-Fe-Co layer with overlayers of Co-Cr, Ni-Fe, Ta and C" J. Appl. Phys.75[10]. 6357-6359 (1994)

[文献書誌] Takakazu TAKAHASHI: "Structural and magretic characteristics of Co_<31>Cr_<19>/Al multilayers deposited by plasma-free sputtring with Kr gas" J. Appl. Phys.75[10]. 6509-6509 (1994)

[文献書誌] Masahiko NAOE: "Preparation of Ni-Fe/Cu multilayers with low coercivity and GMR effect by ion beam sputtering." J. Appl. Phys.75[10]. 6525-6527 (1994)

[文献書誌] Shigeki NAKAGAWA: "Preparation and magnetic properties of Mn_4N films by reactive facing targets sputtering" J. Appl. Phys.75[10]. 6568-6570 (1994)

[文献書誌] Nobuhiro MATSUSHITA: "Preparation and magnetic properties of BaM films with excellent crystallinity by Xe sputtering" J. Appl. Phys.75[10]. 7131-7133 (1994)

[文献書誌] Shigeki NAKAGAWA: "Methods to control internal stress in Co-Cr sputtered films on polymer tape for curl-free recording tape" J. Magn. Magn. Mater.134. 354-361 (1994)

[文献書誌] Masahiko NAOE: "Physics and technolgy of sputtering for depositing magnetic films" J. Magn. Magn. Mater.134. 395-402 (1994)

[文献書誌] Akimitsu MORISAKO: "The effects of Pb addition on crystal structure and magnetic properties of Ba-ferrite sputtered films" J. of Magn. Soc. of Jpn.18[S2]. 69-72 (1994)

[文献書誌] Shigeki NAKAGAWA: "Dual track complimentary type of thin film recording heads for perpendicular magnetic recording" J. of Magn. Soc. of Jpn.18[S2]. 213-216 (1994)

[文献書誌] Masahiko NAOE: "Voidless grainboundary growth process of Co-Cr thin films" J. of Magn. Soc. of Jpn.18[S2]. 331-334 (1994)

[文献書誌] Yasuyoshi MIYAMOTO: "Enhancement in MR field sensitivity of [Ni_<81>Fe_<19>/Cu] Multilayers by control of crysiallite orientation in Fe buffer layer" J. of Magn. Soc. of Jpn.18[S2]. 409-412 (1994)

[文献書誌] Kenji NOMA: "Preparation and recording characteristics of rigid disks using Co-Zn ferrite sputtered films for high density magnetic recording with perpendicular anisotropy" J. of Magn. Soc. of Jpn.18[S2]. 447-450 (1994)

[文献書誌] Masahiko NAOE: "Control of microstructure of Co-Cr thin films by adjusting sputtering condition" J. of Magn. Soc. of Jpn.18[S2]. 479-484 (1994)

[文献書誌] Nobuhiro MATSUSHITA: "Structure and magnetic properties of a hexagonal type ferrite thin films prepared by facing targets sputtering" Proc. the first Magneto-Electronics Int. Symp.11-14 (1994)

[文献書誌] Shigeki NAKAGAWA: "Strict control of C-axis orientation and magnetic anisotropy in Co-Cr thin films for perpendicular magnetic recording media" Proc. the first Magneto-Electronics Int. Symp.15-18 (1994)

1994 年度実績報告書

直江正彦東京工業大学, 工学部, 教授 (40016465)