2002 Fiscal Year Annual Research Report

超高集積化した相互非干渉型磁性メモリセル

Research Project

Project/Area Number	14102029
Research Institution	Osaka University
Principal Investigator	山本雅彦大阪大学, 大学院・工学研究科, 教授 (30029160)
Co-Investigator(Kenkyū-buntansha)	遠藤恭大阪大学, 大学院・工学研究科, 助手 (50335379) 中谷亮一大阪大学, 大学院・工学研究科, 助教授 (60314374)
Keywords	情報記憶デバイス / 磁性メモリ / 静磁結合 / 磁化状態 / 漏洩磁束 / 情報記録層 / 環状メモリセル / 還流磁区
Research Abstract	新世代の情報記憶メモリであるMRAM(Magnetic Random Access Memory)の記憶容量を飛躍的に大きくするための基礎技術を確立することを目的として、サブミクロンオーダー以下の大きさの閉磁路構造を有する磁性メモリセルの磁化過程および磁化状態について検討を行った。 (1)リング状のメモリセルに対する記録方法について検討を行った。従来のリング構造のメモリセルでは、膜面垂直方向に電流を流すことにより、時計回りあるいは反時計回りの磁界を発生しなければ、記録を行うことができなかった。これに対し、Ni-20at%Feからなる直径500-1000nmの円形のリング状のメモリセルの一部を削り、若干の漏洩磁束を生じる構造にすることにより、面内の電流による面内磁界により記録可能であることをマイクロマグネティクス・シミュレーションにより明らかにした。 (2)"(1)"の構造のNi-Fe(10-20nm)リングメモリセル要素素子を形成し、面内の磁界により記録を行い、磁界の向きにより「0」、「1」の2値の記録が可能であることを、磁気力顕微鏡を用いた磁化状態の観察により明らかにした。 (3)リング状のメモリセルに対する記録磁界を低減する新構造を実験およびマイクロマグネティクス・シミュレーションの両面より探索した。これらの検討により、リング部の下に円形磁性層を形成したカップ型メモリセル構造は、非常に低い磁界により記録可能であることを見出した。 (4)"(3)"の構造のカップ型メモリセル材料についての検討を行い、高保磁力のCo-Pt系合金は一方向の磁化状態を維持するためにメモリセルには適さず、低保磁力のNi-Fe系合金は、時計回り・反時計回りの記録状態を容易に実現できるため、メモリセルに適していることを見出した。

Research Products

(14 results)

All Other

All Publications (14 results)

[Publications] Ryoichi Nakatani, Masahiko Yamamoto: "Magnetization Reversal with In-Plane Magnetic Field in Asymmetric Ring Dots"Jpn. J. Appl. Phys.. 42・1. 100-101 (2003)
[Publications] Ryoichi Nakatani, Noritsugu Takahashi, Tetsuo Yoshida, Masahiko Yamamoto: "Magnetic States and Magnetization processes of Ni-Fe/Hf Annular Dots as Candidates of Non-Volatile Memory Cells"Jpn. J. Appl. Phys.. 41・12. 7359-7366 (2002)
[Publications] Ryoichi Nakatani, Takayuki Kusano, Hirotaka Yakame, Masahiko Yamamoto: "Magnetic and Electric Properties in C/Mn/C/Si Multilayers"Jpn. J. Appl. Phys.. 41・10. 5978-5981 (2002)
[Publications] Gyu Bong Cho, Masahiko Yamamoto, Yasuhiro Kamada: "Morphology of Fe Film Grown on Self-Organized SrTiO_3 (001) Substrate with Inclined Angle"Jpn. J. Appl. Phys.. 41・9. 5713-5718 (2002)
[Publications] Yu Shiratsuchi, Masahiko Yamamoto, Yasuhiro Kamada: "Surface Structure of Self-Organised Sapphire (0001) Substrates with Various Inclined Angle"Jpn. J. Appl. Phys.. 41・9. 5719-5725 (2002)
[Publications] Ryoichi Nakatani, Hirotaka Yakame, Yasushi Endo, Masahiko Yamamoto: "Magnetic Properties in Mn/Si-O/Si(100)-substrate systems and Mn/Si-O/Si trilayers"Jpn. J. Appl. Phys.. 42(印刷中). (2003)
[Publications] Yasuhiro Kamada, Akihiro Itoh, Daisuke Takama, Masahiko Yamamoto: "Effects of Hydrogenation on Structure, Transport and Magnetic Properties of the Multilayers Composed of Transition Metals and Rare-Earth Metals"Trans. Mag. Soc. Jpn.. 2・2. 69-75 (2002)
[Publications] Toshiki Kingetsu, Yasuhiro Kamada, Masahiko Yamamoto: "Structure and Magnetic Properties of Metallic Strained Superlattices"J. Magn. Soc. Jpn.. 26・4. 181-187 (2002)
[Publications] Ryoichi Nakatani, Noritsugu Takahashi, Hana Asoh, Yoshio Kawamura, Masahiko: "Fabrication of Ring Dot Arrays as a Candidate of Memory Cells"17th International Colloquium on Magnetic Films and Surfaces. 178-179 (2002)
[Publications] Ryoichi Nakatani, Takayuki Kusano, Hirotaka Yakame, Hideo Hoshiyama, Masahiko Yamamoto: "Ferromagnetism in Multilayers Including Mn Layers"17th International Colloquium on Magnetic Films and Surfaces. 290-291 (2002)
[Publications] Yasuhiro Kamada, Akihiro Itoh, Daisuke Takama, Masahiko Yamamoto: "Effects of Hydrogenation on Structure, Transport and Magnetic Properties of Multilayers Composed of Transition Metals and Rare-Earth Metals"17th International Colloquium on Magnetic Films and Surfaces. 386-387 (2002)
[Publications] Gyu Bong Cho, Masahiko Yamamoto, Yasuhiro Kamada: "Shape-Induced Anisotropy in Fe Films Grown on Inclined StTiO_3 (001) Substrate Made by the Self-Organization Phenomena"17th International Colloquium on Magnetic Films and Surfaces. 36-37 (2002)
[Publications] Toshiki Kingetsu, Yasuhiro Kamada, Masahiko Yamamoto: "Ternary Metallic Strained Superlattices"17th International Colloquium on Magnetic Films and Surfaces. 234-235 (2002)
[Publications] Masahiko Yamamoto, Naoto Sumida, Hitoshi Tampo: "Crossectional TEM observation of metallic superlattices Co/Pt with perpendicular magnetization"Practical electron microscopy and its application to materials. 216 (2002)

2002 Fiscal Year Annual Research Report

超高集積化した相互非干渉型磁性メモリセル

Principal Investigator

山本 雅彦 大阪大学, 大学院・工学研究科, 教授 (30029160)

Research Products

[Publications] Ryoichi Nakatani, Masahiko Yamamoto: "Magnetization Reversal with In-Plane Magnetic Field in Asymmetric Ring Dots"Jpn. J. Appl. Phys.. 42・1. 100-101 (2003)

[Publications] Ryoichi Nakatani, Noritsugu Takahashi, Tetsuo Yoshida, Masahiko Yamamoto: "Magnetic States and Magnetization processes of Ni-Fe/Hf Annular Dots as Candidates of Non-Volatile Memory Cells"Jpn. J. Appl. Phys.. 41・12. 7359-7366 (2002)

[Publications] Ryoichi Nakatani, Takayuki Kusano, Hirotaka Yakame, Masahiko Yamamoto: "Magnetic and Electric Properties in C/Mn/C/Si Multilayers"Jpn. J. Appl. Phys.. 41・10. 5978-5981 (2002)

[Publications] Gyu Bong Cho, Masahiko Yamamoto, Yasuhiro Kamada: "Morphology of Fe Film Grown on Self-Organized SrTiO_3 (001) Substrate with Inclined Angle"Jpn. J. Appl. Phys.. 41・9. 5713-5718 (2002)

[Publications] Yu Shiratsuchi, Masahiko Yamamoto, Yasuhiro Kamada: "Surface Structure of Self-Organised Sapphire (0001) Substrates with Various Inclined Angle"Jpn. J. Appl. Phys.. 41・9. 5719-5725 (2002)

[Publications] Ryoichi Nakatani, Hirotaka Yakame, Yasushi Endo, Masahiko Yamamoto: "Magnetic Properties in Mn/Si-O/Si(100)-substrate systems and Mn/Si-O/Si trilayers"Jpn. J. Appl. Phys.. 42(印刷中). (2003)

[Publications] Yasuhiro Kamada, Akihiro Itoh, Daisuke Takama, Masahiko Yamamoto: "Effects of Hydrogenation on Structure, Transport and Magnetic Properties of the Multilayers Composed of Transition Metals and Rare-Earth Metals"Trans. Mag. Soc. Jpn.. 2・2. 69-75 (2002)

[Publications] Toshiki Kingetsu, Yasuhiro Kamada, Masahiko Yamamoto: "Structure and Magnetic Properties of Metallic Strained Superlattices"J. Magn. Soc. Jpn.. 26・4. 181-187 (2002)

[Publications] Ryoichi Nakatani, Noritsugu Takahashi, Hana Asoh, Yoshio Kawamura, Masahiko: "Fabrication of Ring Dot Arrays as a Candidate of Memory Cells"17th International Colloquium on Magnetic Films and Surfaces. 178-179 (2002)

[Publications] Ryoichi Nakatani, Takayuki Kusano, Hirotaka Yakame, Hideo Hoshiyama, Masahiko Yamamoto: "Ferromagnetism in Multilayers Including Mn Layers"17th International Colloquium on Magnetic Films and Surfaces. 290-291 (2002)

[Publications] Yasuhiro Kamada, Akihiro Itoh, Daisuke Takama, Masahiko Yamamoto: "Effects of Hydrogenation on Structure, Transport and Magnetic Properties of Multilayers Composed of Transition Metals and Rare-Earth Metals"17th International Colloquium on Magnetic Films and Surfaces. 386-387 (2002)

[Publications] Gyu Bong Cho, Masahiko Yamamoto, Yasuhiro Kamada: "Shape-Induced Anisotropy in Fe Films Grown on Inclined StTiO_3 (001) Substrate Made by the Self-Organization Phenomena"17th International Colloquium on Magnetic Films and Surfaces. 36-37 (2002)

[Publications] Toshiki Kingetsu, Yasuhiro Kamada, Masahiko Yamamoto: "Ternary Metallic Strained Superlattices"17th International Colloquium on Magnetic Films and Surfaces. 234-235 (2002)

[Publications] Masahiko Yamamoto, Naoto Sumida, Hitoshi Tampo: "Crossectional TEM observation of metallic superlattices Co/Pt with perpendicular magnetization"Practical electron microscopy and its application to materials. 216 (2002)

山本雅彦大阪大学, 大学院・工学研究科, 教授 (30029160)