Protective layer for magnetic disk
US4861662A · kind A · utility
19Cited by
6References
7Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Feb 3, 1987 |
| Grant date | Aug 29, 1989 |
| Priority date | — |
| Expiry date | Feb 3, 2007 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/30
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A magnetic recording disk composed of a substrate, a magnetic layer, and a protective/lubricative carbon layer is etched and has oxygen embedded into the surface of the disk. This carbon/oxygen surface is extremely smooth, and wears better than prior art disks not having oxygen imbedded in the surface. This altered layer enables a magnetic disk to undergo over twice the number of start/stop cycles without incurring damage from magnetic transducers used to read information from the recording than similar disks prepared without oxygen in the outer layer. A method of plasma etching is used to embed the oxygen into the surface.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.