2003 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, 教授 (60314374)
Keywords	情報記憶デバイス / 磁性メモリ / 磁化過程 / 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)リング構造を有する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、厚さ20nmのNi-20at%Feからなる直径450nmおよび850nmの円形のリング状のメモリセルの一部を削り取った構造とすることにより、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磁気光学効果測定による磁化過程の検討および磁気力顕微鏡を用いた磁化状態の観察により実験的に検証した。 (2)リング構造を有するメモリセルに対する再生方法についての要素技術の検討を行った。"(1)"と同様の2次元構造を有するNi-Fe(10nm)/Mn-Ir(10nm)積層リングセルは、印加磁界の向きにかかわらず、一定の磁化の向きを有することを明らかにした。この構造のセルと"(1)"の構造のセルとを組み合わせることにより、"(1)"の構造のセルに記録した「0」、「1」の2値の情報の再生が可能であることを見出した。 (3)リング状のメモリセルに対する記録磁界を制御する方法についてマイクロマグネティクス・シミュレーションによる検討を行った結果、リング部の下に円形磁性層を形成し、その厚さを変えることにより、情報を記録するために必要な磁界を制御可能なことを見出した。

Research Products

(19 results)

All Other

All Publications (19 results)

[Publications] Ryoichi Nakatani: "Magnetic States and Magnetization Process in Ni-Fe Sub-micron Cup-Shaped Dots"Jpn.J.Appl.Phys.. 42・8. 5024-5029 (2003)
[Publications] Ryoichi Nakatani: "Magnetization chirality due to asymmetrical structure in Ni-Fe annular dots for high-density memory cells"J.Appl.Phys.. 95・11(印刷中). (2004)
[Publications] Ryoichi Nakatani: "Magnetic Properties in Mn/Si-O/Si(100)-substrate systems and Mn/Si-O/Si trilayers"Jpn.J.Appl.Phys.. 42・6A. 3392-3393 (2003)
[Publications] Gyu Bong Cho: "Magnetic Property and Morphology of Fe Film Grown on Self-Organized SrTiO_3 (001) Substrate with Inclined Angle"Jpn.J.Appl.Phys.. 42・10. 6543-6550 (2003)
[Publications] Yu Shiratsuchi: "Superparamagnetic Behavior of Fe Ultrathin Films Grown on Al_2O_3 (0001) Substrates"J.Appl.Phys.. 94・12. 7675-7679 (2003)
[Publications] Ryoichi Nakatani: "Ferromagnetism in Mn/X/Si (X=B, BN, B_4C, SiC) trilayers"Science and Technology of Advanced Materials. 5・1-2. 69-72 (2004)
[Publications] S.Anisul Haque: "Magnetic logic gate for binary computing"Science and Technology of Advanced Materials. 5・1-2. 79-82 (2004)
[Publications] Yu Shiratsuchi: "Thickness dependence of magnetic state of Fe thin films grown on Al_2O_3(0001) substrates with inclined angle"Science and Technology of Advanced Materials. 5・1-2. 73-78 (2004)
[Publications] Gyu-Bong Cho: "Film thickness dependence on morphology of Fe films on self-organized SrTiO_3(0001) substrates with inclined angles"Science and Technology of Advanced Materials. 5・1-2. 89-94 (2004)
[Publications] Yasushi Endo: "Effects of hydrogenation on structure and magnetic properties of Fe/La multilayers"Science and Technology of Advanced Materials. 5・1-2. 95-100 (2004)
[Publications] Hiroshi Naganuma: "Magnetic and electrical properties of iron nitride films having both amorphous matrices and nanocrystalline grains"Science and Technology of Advanced Materials. 5・1-2. 101-106 (2004)
[Publications] Hiroshi Naganuma: "Magnetic properties of weak itinerant ferromagnetic ξ-Fe_2N film"Science and Technology of Advanced Materials. 5・1-2. 83-87 (2004)
[Publications] Masahiko Yamamoto: "Magnetic Properties and Structures of Nanofabricated Thin Films and Multilayers"Proc of the Inter.Symp. On Future-Oriented Interdisciplinary Materials Science. 5 (2003)
[Publications] Yu Shiratsuchi: "Magnetic State and Magnetic Anisotropy of Fe Thin Films Grown on Al_2O_3 (0001) Inclined Substrates"Proc. of the 8^<th> IUMRS International Conference on Advanced Materials. 1・A&B. 248 (2003)
[Publications] Yasushi Endo: "Effect of Hydrogenation on the Interlayer Exchange Coupling of Fe/(Y, La)/Fe Trilayers"Proc. of the 8^<th> IUMRS International Conference on Advanced Materials. 1・A&B. 246 (2003)
[Publications] S.Anisul Haque: "Permalloy Nanodots for Binary Logic Operation"International Conference on Atomically Controlled Surfaces, Interfaces and Nanostructures. 267 (2003)
[Publications] Gyu-Bong Cho: "Surface Features of Self-Organized SrTiO_3 (001) Substrates Inclined in [100] and [110] Directions"International Conference on Atomically Controlled Surfaces, Interfaces and Nanostructures. 341 (2003)
[Publications] Yasushi Endo: "Hydrogenation Effects on the Structure and Magnetic Properties of TM/REM (TM=Fe ; REM=Y, La) Multilayers"International Conference on Atomically Controlled Surfaces, Interfaces and Nanostructures. 580 (2003)
[Publications] Masahiko Yamamoto: "Recenet Progress in Materials Design and Devices based on Nano-Magnetism"Int.Conf.on Structure, Processing and Properties of Materials. 54 (2004)

2003 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: "Magnetic States and Magnetization Process in Ni-Fe Sub-micron Cup-Shaped Dots"Jpn.J.Appl.Phys.. 42・8. 5024-5029 (2003)

[Publications] Ryoichi Nakatani: "Magnetization chirality due to asymmetrical structure in Ni-Fe annular dots for high-density memory cells"J.Appl.Phys.. 95・11(印刷中). (2004)

[Publications] Ryoichi Nakatani: "Magnetic Properties in Mn/Si-O/Si(100)-substrate systems and Mn/Si-O/Si trilayers"Jpn.J.Appl.Phys.. 42・6A. 3392-3393 (2003)

[Publications] Gyu Bong Cho: "Magnetic Property and Morphology of Fe Film Grown on Self-Organized SrTiO_3 (001) Substrate with Inclined Angle"Jpn.J.Appl.Phys.. 42・10. 6543-6550 (2003)

[Publications] Yu Shiratsuchi: "Superparamagnetic Behavior of Fe Ultrathin Films Grown on Al_2O_3 (0001) Substrates"J.Appl.Phys.. 94・12. 7675-7679 (2003)

[Publications] Ryoichi Nakatani: "Ferromagnetism in Mn/X/Si (X=B, BN, B_4C, SiC) trilayers"Science and Technology of Advanced Materials. 5・1-2. 69-72 (2004)

[Publications] S.Anisul Haque: "Magnetic logic gate for binary computing"Science and Technology of Advanced Materials. 5・1-2. 79-82 (2004)

[Publications] Yu Shiratsuchi: "Thickness dependence of magnetic state of Fe thin films grown on Al_2O_3(0001) substrates with inclined angle"Science and Technology of Advanced Materials. 5・1-2. 73-78 (2004)

[Publications] Gyu-Bong Cho: "Film thickness dependence on morphology of Fe films on self-organized SrTiO_3(0001) substrates with inclined angles"Science and Technology of Advanced Materials. 5・1-2. 89-94 (2004)

[Publications] Yasushi Endo: "Effects of hydrogenation on structure and magnetic properties of Fe/La multilayers"Science and Technology of Advanced Materials. 5・1-2. 95-100 (2004)

[Publications] Hiroshi Naganuma: "Magnetic and electrical properties of iron nitride films having both amorphous matrices and nanocrystalline grains"Science and Technology of Advanced Materials. 5・1-2. 101-106 (2004)

[Publications] Hiroshi Naganuma: "Magnetic properties of weak itinerant ferromagnetic ξ-Fe_2N film"Science and Technology of Advanced Materials. 5・1-2. 83-87 (2004)

[Publications] Masahiko Yamamoto: "Magnetic Properties and Structures of Nanofabricated Thin Films and Multilayers"Proc of the Inter.Symp. On Future-Oriented Interdisciplinary Materials Science. 5 (2003)

[Publications] Yu Shiratsuchi: "Magnetic State and Magnetic Anisotropy of Fe Thin Films Grown on Al_2O_3 (0001) Inclined Substrates"Proc. of the 8^<th> IUMRS International Conference on Advanced Materials. 1・A&B. 248 (2003)

[Publications] Yasushi Endo: "Effect of Hydrogenation on the Interlayer Exchange Coupling of Fe/(Y, La)/Fe Trilayers"Proc. of the 8^<th> IUMRS International Conference on Advanced Materials. 1・A&B. 246 (2003)

[Publications] S.Anisul Haque: "Permalloy Nanodots for Binary Logic Operation"International Conference on Atomically Controlled Surfaces, Interfaces and Nanostructures. 267 (2003)

[Publications] Gyu-Bong Cho: "Surface Features of Self-Organized SrTiO_3 (001) Substrates Inclined in [100] and [110] Directions"International Conference on Atomically Controlled Surfaces, Interfaces and Nanostructures. 341 (2003)

[Publications] Yasushi Endo: "Hydrogenation Effects on the Structure and Magnetic Properties of TM/REM (TM=Fe ; REM=Y, La) Multilayers"International Conference on Atomically Controlled Surfaces, Interfaces and Nanostructures. 580 (2003)

[Publications] Masahiko Yamamoto: "Recenet Progress in Materials Design and Devices based on Nano-Magnetism"Int.Conf.on Structure, Processing and Properties of Materials. 54 (2004)

山本雅彦大阪大学, 大学院・工学研究科, 教授 (30029160)