发明名称 |
Perpendicular magnetic recording medium |
摘要 |
This document discloses a perpendicular magnetic recording medium in which the magnetic anisotropy of a magnetic recording layer is raised and the thermal stability of recorded signals is improved without changing the conventional stacked configuration. A perpendicular magnetic recording medium is formed by stacking at least an intermediate layer, a second underlayer, and a magnetic recording layer in this order on a nonmagnetic base. The intermediate layer is either a single layer of Ru or a Ru-based alloy, or a stacked structure of a nonmagnetic alloy film including Co and Cr and a film of Ru or a Ru-based alloy. The second underlayer includes Co in the range from 30 at % to 75 at %, Cr in the range from 20 at % to 60 at %, and W in the range from 0.1 at % to 10 at %, and has a thickness in the range from 0.1 nm to 1.0 nm. |
申请公布号 |
US8846219(B2) |
申请公布日期 |
2014.09.30 |
申请号 |
US201213417198 |
申请日期 |
2012.03.09 |
申请人 |
Fuji Electric Co., Ltd. |
发明人 |
Hozumi Yasuaki |
分类号 |
G11B5/66 |
主分类号 |
G11B5/66 |
代理机构 |
Rabin & Berdo, P.C. |
代理人 |
Rabin & Berdo, P.C. |
主权项 |
1. A perpendicular magnetic recording medium, comprising:
a nonmagnetic base; a first underlayer that is disposed over the nonmagnetic base; an intermediate layer that is disposed over the first underlayer, the intermediate layer being either a single layer of Ru or a Ru-based alloy, or a stacked structure of a nonmagnetic alloy film including Co and Cr and a film of Ru or a Ru-based alloy; a second underlayer on the intermediate layer, the second intermediate layer including Co in a range from 30 at % to 75 at %, Cr in a range from 20 at % to 60 at %, and W in a range from 0.1 at % to 10 at %, the second underlayer having a thickness in a range from 0.5 nm to 1.0 nm; and a magnetic recording layer on the second underlayer, wherein the second underlayer is substantially free of oxides. |
地址 |
Kawasaki-Shi JP |