Magnetic recording medium including plural FePt alloy layers including carbon, oxides or nitrides
US8679654B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 13, 2012 |
| Grant date | Mar 25, 2014 |
| Priority date | — |
| Expiry date | Jun 1, 2032 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC22C2202/02
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Surface flatness of magnetic recording medium to which a magnetic recording layer made of L10 FePt magnetic alloy thin film, with distance between a magnetic head and a magnetic recording medium sufficiently reduced. The magnetic recording layer includes: magnetic layers containing a magnetic alloy including Fe and Pt as principal materials; and one non-magnetic material selected from carbon, oxide and nitride. The first magnetic layer disposed closer to a substrate has a granular structure in which magnetic alloy grains including FePt alloy as the principal material are separated from grain boundaries including the non-magnetic material as the principal material. The second magnetic layer disposed closer to the surface than the first magnetic layer is fabricated so as to have a homogeneous structure in which an FePt alloy and the non-magnetic material are mixed in a state finer than diameters of the FePt magnetic alloy grains in the first magnetic layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.