Perpendicular magnetic recording medium and system having a magnetic recording layer with a perpendicular recording layer, a magnetic coupling layer, and a writing assist layer
US8000060B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 17, 2008 |
| Grant date | Aug 16, 2011 |
| Priority date | — |
| Expiry date | Jan 19, 2030 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/855
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Embodiments of the present invention provide a perpendicular magnetic recording medium having a substrate, a magnetic recording layer and a protective layer. The magnetic recording layer includes a perpendicular recording layer, a magnetic coupling layer and a writing assist layer. The perpendicular recording layer is a Co alloy layer containing an oxide disposed between the magnetic coupling layer and the substrate. The magnetic coupling layer is a ferromagnetic layer disposed between the perpendicular recording layer and the writing assist layer. The writing assist layer is a ferromagnetic layer disposed between the magnetic coupling layer and the protective layer. The saturation magnetization of the magnetic coupling layer is lower than the saturation magnetization of the perpendicular recording layer or the writing assist layer. The thickness of the magnetic coupling layer is 1 nm or more and 3 nm or less.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.