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Patent US4556597A successfully refreshed from Google Patents.
US4556597A
Expired / Lapsed
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Ion doped servo pattern for magnetic recording disk
Assignee: HGST Netherlands BV
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Filing: 1983-08-22
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Granted: 1985-12-03
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Expires: 2003-08-22
Abstract
Abstract A magnetic recording disk substrate is provided with a capacitive servo pattern by implanting dopant material in the substrate to modify the substrate conductivity in a desired servo pattern.
Inventors
- 👤 John S. Best
- 👤 David C. Bullock
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 17:01
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/74; G11B5/82; G11B5/48; G11B5/58; G11B5/596; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/24; Y10T428/24802; Y10T428/24851
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
47 words
A magnetic recording disk structure comprising: a substrate, said substrate being made of a dopable material, said substrate having doped areas therein which modify the conductivity or permitivity of said substrate to form a capacitive track following servo pattern, and a magnetic recording layer on said substrate.
Claim 2
Dependent Claim
47 words
A magnetic recording disk structure comprising: a substrate, said substrate being made of a dopable material, said substrate having doped areas therein which modify the conductivity or permitivity of said substrate to form a capacitive track following servo pattern, and a magnetic recording layer on said substrate.
Claim 3
Dependent Claim
17 words
A magnetic recording disk in accordance with claim 1 in which said magnetic recording layer is nonmetallic.
Claim 4
Dependent Claim
19 words
A magnetic recording disk in accordance with claim 1 in which said dopant areas are produced by ion implantation.
Claim 5
Dependent Claim
15 words
A magnetic recording disk in accordance with claim 1 in which said substrate is silicon.
Claim 6
Dependent Claim
16 words
A magnetic recording disk in accordance with claim 1 in which said substrate is gallium arsenide.
Claim 7
Dependent Claim
15 words
A magnetic recording disk in accordance with claim 1 in which said substrate is germanium.
Claim 8
Dependent Claim
15 words
A magnetic recording disk in accordance with claim 1 in which said substrate is sapphire.
Claim 9
Dependent Claim
15 words
A magnetic recording disk in accordance with claim 1 in which said substrate is polysilicon.
Claim 10
Dependent Claim
19 words
A magnetic recording disk in accordance with claim 1 in which said dopant areas are produced by thermal diffusion.
Claim 11
Dependent Claim
22 words
A magnetic recording disk in accordance with claim 1 in which said dopant is an n+ material in a p type substrate.
Claim 12
Dependent Claim
22 words
A magnetic recording disk in accordance with claim 1 in which said dopant is a p+ material in an n type substrate.
Claim 13
Dependent Claim
22 words
A magnetic recording disk in accordance with claim 1 in which said dopant is a p+ material in a p type substrate.
Claim 14
Dependent Claim
22 words
A magnetic recording disk in accordance with claim 1 in which said dopant is an n+ material in a n type substrate.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-12-02 | 1989-06-03 | 1989-12-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-12-02 | 1993-06-03 | 1993-12-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-12-02 | 1997-06-03 | 1997-12-03 | $7700.00 | Window Closed / Lapsed |