US4929500A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Corrosion resistant magnetic disk
Assignee: WD Media LLC
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Filing: 1986-04-03
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Granted: 1990-05-29
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Expires: 2006-04-03
Abstract
Abstract A film of magnetic recording media is covered with a layer comprising ZrO 2 . Advantageously, the ZrO 2 layer inhibits corrosion in the underlying magnetic recording media. The ZrO 2 layer also exhibits desirable mechanical properties, e.g. reduced stiction. In one embodiment of our invention, the ZrO 2 is sputtered onto the magnetic recording media.
Inventors
- 👤 Tsutomu T. Yamashita
- 👤 Ching-Cheng Shir
- 👤 Tu Chen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 18:47
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/72; G11B5/722; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/26; Y10T428/263; Y10T428/264; Y10T428/265
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
62 words
A hard magnetic disk for use in magnetic induction recording comprising: a nonmagnetic substrate; a magnetic film of recording media formed on said substrate; and a protective layer formed above said film, said protective layer comprising sputtered ZrO 2 and a stabilizer, said protective layer being the uppermost vacuum-deposited layer on said disk and being substantially free of other vacuum-deposited solid lubricants.
Claim 2
Dependent Claim
62 words
A hard magnetic disk for use in magnetic induction recording comprising: a nonmagnetic substrate; a magnetic film of recording media formed on said substrate; and a protective layer formed above said film, said protective layer comprising sputtered ZrO 2 and a stabilizer, said protective layer being the uppermost vacuum-deposited layer on said disk and being substantially free of other vacuum-deposited solid lubricants.
Claim 3
Dependent Claim
16 words
The structure of claim 1 wherein said protective layer is the top layer of said structure.
Claim 4
Dependent Claim
19 words
The structure of claim 1 wherein said protective layer has a thickness greater than or equal to 5 nm.
Claim 5
Dependent Claim
16 words
Structure of claim 1 wherein said protective layer has a thickness between 10 and 60 nm.
Claim 6
Dependent Claim
22 words
Structure of claim 1 further comprising an additional layer between said recording media and said protective layer, said additional layer comprising chromium.
Claim 7
Dependent Claim
13 words
Structure of claim 1 wherein said recording media is a cobalt based alloy.
Claim 8
Dependent Claim
13 words
Structure of claim 1 wherein said recording media is an iron based alloy.
Claim 9
Independent Claim
69 words
A method for forming a hard magnetic disk for use in magnetic induction recording comprising the steps of: forming a magnetic film of recording media on a nonmagnetic substrate; and sputtering a protective layer on said recording media, said protective layer comprising ZrO 2 and a stablizer, said protective layer being the uppermost vacuum-deposited layer on said hard magnetic disk and being substantially free of other vacuum-deposited solid lubricants.
Claim 10
Independent Claim
69 words
A method for forming a hard magnetic disk for use in magnetic induction recording comprising the steps of: forming a magnetic film of recording media on a nonmagnetic substrate; and sputtering a protective layer on said recording media, said protective layer comprising ZrO 2 and a stablizer, said protective layer being the uppermost vacuum-deposited layer on said hard magnetic disk and being substantially free of other vacuum-deposited solid lubricants.
Claim 11
Dependent Claim
31 words
The method of claim 8 wherein said step of forming a protective layer comprises a step of sputtering said second layer using a sputtering target, said sputtering target including a stabilizer.
Claim 12
Dependent Claim
16 words
The method of claim 8 wherein said protective layer has a thickness greater than 5 nm.
Claim 13
Dependent Claim
16 words
The method of claim 8 wherein said protective layer is between 10 and 60 nm thick.
Claim 14
Dependent Claim
62 words
Structure for use in magnetic induction recording comprising: a nonmagnetic substrate; a magnetic film of recording media formed on said substrate; and a protective layer formed above said film, said protective layer comprising sputtered ZrO 2 and a stabilizer, said protective layer being the uppermost vacuum-deposited layer on said structure, said protective layer being substantially free of other vacuum deposited solid lubricants.
Claim 15
Dependent Claim
62 words
Structure for use in magnetic induction recording comprising: a nonmagnetic substrate; a magnetic film of recording media formed on said substrate; and a protective layer formed above said film, said protective layer comprising sputtered ZrO 2 and a stabilizer, said protective layer being the uppermost vacuum-deposited layer on said structure, said protective layer being substantially free of other vacuum deposited solid lubricants.
Claim 16
Independent Claim
70 words
A method for forming a magnetic recording device for use in magnetic induction recording comprising the steps of: forming a magnetic film of recording media on a nonmagnetic substrate; and sputtering a protective layer on said recording media, said protective layer comprising ZrO 2 and a stabilizer, said protective layer being the uppermost vacuum-deposited layer on said recording device, said protective layer being substantially free of other vacuum-deposited solid lubricants.
Claim 17
Independent Claim
70 words
A method for forming a magnetic recording device for use in magnetic induction recording comprising the steps of: forming a magnetic film of recording media on a nonmagnetic substrate; and sputtering a protective layer on said recording media, said protective layer comprising ZrO 2 and a stabilizer, said protective layer being the uppermost vacuum-deposited layer on said recording device, said protective layer being substantially free of other vacuum-deposited solid lubricants.
Claim 18
Dependent Claim
77 words
Structure for use in magnetic induction recording comprising: a nonmagnetic substrate; a magnetic film of recording media formed on said substrate; a sputtered protective layer formed above said film, said protective layer consisting essentially of ZrO 2 and a stabilizer, said protective layer being the uppermost vacuum-deposited layer on said structure, wherein said ZrO 2 is the material having the greatest effect on the tribological properties of said structure of any component within said sputtered protective layer.
Claim 19
Dependent Claim
77 words
Structure for use in magnetic induction recording comprising: a nonmagnetic substrate; a magnetic film of recording media formed on said substrate; a sputtered protective layer formed above said film, said protective layer consisting essentially of ZrO 2 and a stabilizer, said protective layer being the uppermost vacuum-deposited layer on said structure, wherein said ZrO 2 is the material having the greatest effect on the tribological properties of said structure of any component within said sputtered protective layer.
Claim 20
Independent Claim
87 words
A method for forming a magnetic recording device for use in magnetic induction recording comprising the steps of: forming a magnetic film of recording media on a nonmagnetic substrate; and sputtering a protective layer on said recording media, said protective layer consisting essentially of ZrO 2 and a stabilizer, said protective layer being the uppermost vacuum-deposited layer on said recording device, wherein said ZrO 2 is the material having the greatest effect on the tribological properties of said structure of any component within said sputtered protective layer.
Claim 21
Independent Claim
87 words
A method for forming a magnetic recording device for use in magnetic induction recording comprising the steps of: forming a magnetic film of recording media on a nonmagnetic substrate; and sputtering a protective layer on said recording media, said protective layer consisting essentially of ZrO 2 and a stabilizer, said protective layer being the uppermost vacuum-deposited layer on said recording device, wherein said ZrO 2 is the material having the greatest effect on the tribological properties of said structure of any component within said sputtered protective 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) | 1993-05-28 | 1993-11-27 | 1994-05-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-05-28 | 1997-11-27 | 1998-05-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-05-28 | 2001-11-27 | 2002-05-29 | $7700.00 | Window Closed / Lapsed |