Process for fabricating thin film metal alloy magnetic recording disks to selectively variable coercivities
US5149409A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 11, 1991 |
| Grant date | Sep 22, 1992 |
| Priority date | — |
| Expiry date | Jan 11, 2011 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23C14/0635
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
In the fabrication of thi film cobalt alloy magnetic recording disks by sputter-deposition, the coercivity of the disks can be selectively varied by introducing a predetermined amount of hydrocarbon gas, such as methane, into the argon-based sputtering atmosphere. The flow rate of the hydrocarbon gas into the sputtering chamber is directly related to the coercivity of the resulting disks. This permits the coercivity of the disks to be controlled without the necessity of changing the composition of the cobalt alloy sputtering targets, and without the necessity of changing the thickness of an underlying between the disk substrate and the magnetic layer. The use of hydrocarbon gas in the reactive sputtering of the cobalt alloy magnetic layer in the disks does not affect the intrinsic media noise of the disks, thus allowing for the manufacturing of disks with high signal-to-noise ratio (SNR) of the readback signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.