(Fe-Pt)-Oxide複合材料を用いた垂直二層膜媒体  [in Japanese] (Fe-Pt)-Oxide Composite Films for Perpendicular Double-Layered Media  [in Japanese]

Fe-Pt垂直二層膜媒体における磁区寸法を小さくし媒体雑音を低減するため、酸化物添加を検討した。MgO添加は、他のAl_2O_3、SiO_2添加に比べ比較的低い製膜温度でFe-Pt相の規則化が実現でき、純粋Fe-Pt系に比べ磁区寸法を低減できることがわかった。(Fe-Pt)-MgO複合材料を用いた二層膜媒体は高記録分解能性を示し、700 kFRPIの記録パターンも観察された。TEM観察の結果、(Fe-Pt)-MgO膜では、Fe-Pt相とMgO相との間に膜面内方向での格子整合の可能性が示唆された。一方、(Fe-Pt)SiO_2膜は、粒径約10nmのFe-Pt相がSiO_2相と思われるチャネルで分離された垂直磁気異方性を有するナノグラニュラー膜であることがわかった。

Preparation of (Fe-Pt)-Oxide composite films was studied, aiming at reducing a domain size of Fe-Pt double-layered media. It found that a new (Fe-Pt)-MgO composite film exhibited a lower formation temperature of ordered phase than that for composite films with other additives such as Al_2O_3 and SiO_2. A domain size of the (Fe-Pt)-MgO film was smaller than that of a pure Fe-Pt film. A high density recorded pattern of 700 kFRPI was observed for the (Fe-Pt)-MgO double-layered medium. TEM observations for the (Fe-Pt)-MgO composite film suggest epitaxial relationship between the Fe-Pt grain and the MgO grain in the film lateral direction. The (Fe-Pt)-SiO_2 film was constructed with a nano-granular structure consisting of the (001) oriented Fe-Pt grains separated by channels of amorphous SiO_2 phase.