Magnetic recording medium with an underlayer and a cobalt-based magnetic layer
US4654276A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 29, 1986 |
| Grant date | Mar 31, 1987 |
| Priority date | — |
| Expiry date | Apr 29, 2006 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/12944
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An improved cobalt-platinum (CoPt) thin film metal alloy media for horizontal magnetic recording has a coercivity substantially greater than prior CoPt thin film metal alloy media. A tungsten underlayer between the substrate and the CoPt magnetic layer improves the coercivity above that of media wiht conventional underlayers, such as chromium. The coercivity of the CoPt layer can be increased even further if the CoPt film is deposited in such a manner as to form an intermetallic compound of Co.sub.3 W in the interface region between the tungsten underlayer and the CoPt magnetic layer. The tungsten underlayer also improves the magnetic properties of the media when the magnetic layer is an alloy of cobalt-platinum-chromium (CoPtCr).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.