US5066552A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low noise thin film metal alloy magnetic recording disk
Assignee: HGST Netherlands BV
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Filing: 1989-08-16
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Granted: 1991-11-19
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Expires: 2009-08-16
Abstract
Abstract An improved CoPt alloy magnetic recording disk for horizontal recording has a magnetic recording layer which includes oxygen, the oxygen being present preferably in the range of approximately 5 to 30 atomic percent. The resulting disk structure has substantially decreased intrinsic media noise at high linear recording density.
Inventors
- 👤 James K. Howard
- 👤 Randall G. Simmons
- 👤 Tadashi Yogi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 10:07
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/64; G11B5/65; G11B5/658; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10S428/922; Y10S428/9265; Y10S428/928; Y10T; Y10T428/00; Y10T428/12; Y10T428/12465; Y10T428/12493; Y10T428/1266; Y10T428/12771; Y10T428/12861; Y10T428/12931
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
56 words
A magnetic recording disk for horizontal recording comprising: a rigid substrate; and a sputter deposited magnetic layer formed over the substrate, the magnetic layer having a composition comprising cobalt, platinum and oxygen, the oxygen being present in the magnetic layer in an amount greater than approximately 5 atomic percent and less than approximately 30 atomic percent.
Claim 2
Dependent Claim
56 words
A magnetic recording disk for horizontal recording comprising: a rigid substrate; and a sputter deposited magnetic layer formed over the substrate, the magnetic layer having a composition comprising cobalt, platinum and oxygen, the oxygen being present in the magnetic layer in an amount greater than approximately 5 atomic percent and less than approximately 30 atomic percent.
Claim 3
Dependent Claim
18 words
A disk according to claim 1 further comprising a non-magnetic underlayer between the substrate and the magnetic layer.
Claim 4
Dependent Claim
11 words
A disk according to claim 2 wherein the underlayer is chromium.
Claim 5
Dependent Claim
12 words
A disk according to claim 1 wherein the magnetic layer includes chromium.
Claim 6
Dependent Claim
16 words
A disk according to claim 1 further comprising a protective overcoat formed over the magnetic layer.
Claim 7
Dependent Claim
62 words
A magnetic recording disk for horizontal recording comprising: a rigid substrate; a sputter deposited magnetic layer formed over the substrate and having a composition comprising cobalt, platinum and oxygen, the oxygen being present in the magnetic layer in an amount greater than approximately 5 atomic percent and less than approximately 30 atomic percent; and a protective overcoat formed over the magnetic layer.
Claim 8
Dependent Claim
62 words
A magnetic recording disk for horizontal recording comprising: a rigid substrate; a sputter deposited magnetic layer formed over the substrate and having a composition comprising cobalt, platinum and oxygen, the oxygen being present in the magnetic layer in an amount greater than approximately 5 atomic percent and less than approximately 30 atomic percent; and a protective overcoat formed over the magnetic layer.
Claim 9
Dependent Claim
79 words
In a process for the fabrication of a thin film magnetic recording disk of the type having a magnetic layer comprising cobalt and platinum wherein the magnetic layer is formed by sputter deposition, an improvement comprising the steps of introducing oxygen into the sputtering atmosphere during the deposition of the magnetic layer in an amount sufficient to incorporate oxygen into the magnetic layer in an amount greater than approximately 5 atomic percent and less than approximately 30 atomic percent.
Claim 10
Dependent Claim
79 words
In a process for the fabrication of a thin film magnetic recording disk of the type having a magnetic layer comprising cobalt and platinum wherein the magnetic layer is formed by sputter deposition, an improvement comprising the steps of introducing oxygen into the sputtering atmosphere during the deposition of the magnetic layer in an amount sufficient to incorporate oxygen into the magnetic layer in an amount greater than approximately 5 atomic percent and less than approximately 30 atomic percent.
Claim 11
Dependent Claim
24 words
The improved process according to claim 7 further comprising the step of heat treating the disk after the sputter deposition of the magnetic layer.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-11-18 | 1995-05-20 | 1995-11-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-11-18 | 1999-05-20 | 1999-11-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-11-18 | 2003-05-20 | 2003-11-19 | $7700.00 | Window Closed / Lapsed |