Magnetic recording disk with perpendicular magnetic recording layer and multilayered underlayer structure
US6537638B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 13, 2000 |
| Grant date | Mar 25, 2003 |
| Priority date | — |
| Expiry date | Dec 13, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S428/90
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A perpendicular magnetic recording disk has an underlayer structure that causes the magnetic layer to have perpendicular magnetic anisotropy and high signal-to-noise ratio (SNR). The underlayer structure comprises a B2 type body-centered-cubic (BCC) material, such as the binary alloys NiAl, RuAl and RuTi, as an underlayer, and a Ti or TiCr alloy sublayer formed directly on the underlayer. The magnetic layer, such as a CoCrPt alloy, is deposited directly on the sublayer. The magnetic layer has perpendicular magnetic anisotropy due to the sublayer yet excellent SNR because of the smaller grain size of the sublayer material formed directly on the B2 type underlayer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.