Patterned perpendicular magnetic recording medium with ultrathin oxide film and reduced switching field distribution
US8268461B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 16, 2011 |
| Grant date | Sep 18, 2012 |
| Priority date | — |
| Expiry date | Apr 20, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/855
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A patterned perpendicular magnetic recording disk has a Co-alloy recording layer patterned into discrete data islands arranged in concentric tracks and exhibits a narrow switching field distribution (SFD). The disk includes a substrate, a NiTa alloy planarizing layer on the substrate, a nonmagnetic Ru-containing underlayer on the planarizing layer, an oxide-free Co alloy magnetic recording layer, and an ultrathin oxide film between the Ru-containing layer and the Co-alloy magnetic recording layer. The oxide film may be an oxide selected from a Ta-oxide, a Co-oxide and a Ti-oxide, and is ultrathin so that it may be considered a discontinuous film. The planarizing layer and ultrathin oxide film improve the growth homogeneity of the Co-alloy recording layer, so that the patterned disk with data islands shows significantly reduced SFD.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.