Magnetic disk for longitudinal recording comprising an amorphous intermediate layer
US5153044A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 21, 1991 |
| Grant date | Oct 6, 1992 |
| Priority date | — |
| Expiry date | Oct 21, 2011 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/12944
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method for manufacturing a disk includes the step of forming a first nickel-phosphorus alloy layer on an aluminum substrate, e.g., by electroless plating. A second nickel-phosphorus layer is then sputtered onto the first nickel-phosphorus layer, and a magnetic alloy is sputtered onto the second nickel-phosphorus layer. The magnetic alloy is typically sputtered immediately after the second nickel-phosphorus layer is formed without removing the disk from the sputtering apparatus between the time the second nickel-phosphorus layer is formed and the time the magnetic alloy is formed. Because of this, contaminants are not capable of lodging on or affecting the surface of the disk prior to formation of the magnetic alloy. The second nickel-phosphorus layer is typically amorphous and therefore masks any nonuniformities in the surface of the first nickel-phosphorus layer. Because of this, the second nickel-phosphorus layer serves as a uniform nucleation surface for forming the magnetic alloy, and thus the magnetic alloy exhibits uniform magnetic characteristics.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.