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US5853820A
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US
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Controlled laser texturing glass-ceramic substrates for magnetic recording media
Assignee: Seagate Technology LLC
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Filing: 1997-06-23
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Granted: 1998-12-29
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Expires: 2017-06-23
Abstract
Abstract The height of protrusions formed during laser texturing a glass-ceramic substrate is controlled by controlling the amount of the crystalline-phase of the substrate, to less than 70% by volume. In an embodiment, the amount of crystalline-phase is controlled by heating under controlled conditions to convert a glass substrate into the glass-ceramic substrate comprising a controlled amount of crystalline phase.
Inventors
- 👤 David Kuo
- 👤 Don Polensky
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 11:19
CPC Classifications
C; C03; C03C; C03C23/00; C03C23/0005; C03C23/0025; B; B05; B05D; B05D3/00; B05D3/02; B05D5/00; B05D5/12; B32; B32B; B32B17/00; B32B17/06; G; G11; G11B; G11B5/00; G11B5/62; G11B5/73; G11B5/739; G11B5/73911; G11B5/73921; G11B5/84; G11B5/8404; Y; Y10; Y10S; Y10S428/00; Y10S428/90
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
53 words
A method of manufacturing a magnetic recording medium, which method comprises: texturing a surface of a glass-ceramic substrate with a pulsed, focused laser light beam to form a plurality of protrusions on and extending above the substrate surface; wherein the crystalline phase of the glass-ceramic substrate is less than about 70% by volume.
Claim 2
Independent Claim
53 words
A method of manufacturing a magnetic recording medium, which method comprises: texturing a surface of a glass-ceramic substrate with a pulsed, focused laser light beam to form a plurality of protrusions on and extending above the substrate surface; wherein the crystalline phase of the glass-ceramic substrate is less than about 70% by volume.
Claim 3
Dependent Claim
17 words
The method according to claim 1, wherein the crystalline phase is less than about 50% by volume.
Claim 4
Dependent Claim
19 words
The method according to claim 2, wherein the density of the glass-ceramic substrate is less than about 2.4255 g/cc.
Claim 5
Dependent Claim
19 words
The method according to claim 1, wherein the density of the glass-ceramic substrate is less than about 2.44 g/cc.
Claim 6
Dependent Claim
40 words
The method according to claim 1, comprising: preparing a glass substrate; heating to convert the glass substrate into a glass-ceramic substrate comprising less than about 70% by volume of crystalline phase; and laser texturing the surface of the glass-ceramic substrate.
Claim 7
Dependent Claim
27 words
The method according to claim 5, comprising heating to convert the glass substrate into a glass-ceramic substrate comprising less than about 50% by volume of crystalline phase.
Claim 8
Dependent Claim
18 words
The method according to claim 5, wherein the glass-ceramic substrate has a density less than about 2.44 g/cc.
Claim 9
Dependent Claim
18 words
The method according to claim 7, wherein the glass-ceramic substrate has a density less than about 2.4255 g/cc.
Claim 10
Dependent Claim
24 words
The method according to claim 1, comprising laser texturing the substrate surface with a laser light beam derived from a CO 2 laser source.
Claim 11
Dependent Claim
13 words
The method according to claim 1, comprising rotating the substrate during laser texturing.
Claim 12
Dependent Claim
20 words
The method according to claim 1, comprising laser texturing a portion of the substrate surface to form a landing zone.
Claim 13
Dependent Claim
18 words
The method according to claim 1, further comprising depositing a magnetic layer on the laser textured substrate surface.
Claim 14
Dependent Claim
35 words
The method according to claim 1, comprising: depositing an underlayer on the laser textured substrate surface; and depositing a magnetic layer on the underlayer; wherein the textured surface is substantially replicated on subsequently deposited layers.
Claim 15
Dependent Claim
19 words
The method according to claim 1, comprising controlling the height of the protrusions to less than about 100 nm.
Claim 16
Independent Claim
61 words
A method of manufacturing a magnetic recording medium, which method comprises: texturing a surface of a glass-ceramic substrate with a pulsed, focused laser light beam to form a plurality of protrusions on and extending above the substrate surface; and controlling the height of the protrusions by controlling the amount of crystalline phase of the glass-ceramic substrate under about 70% by volume.
Claim 17
Independent Claim
61 words
A method of manufacturing a magnetic recording medium, which method comprises: texturing a surface of a glass-ceramic substrate with a pulsed, focused laser light beam to form a plurality of protrusions on and extending above the substrate surface; and controlling the height of the protrusions by controlling the amount of crystalline phase of the glass-ceramic substrate under about 70% by volume.
Claim 18
Dependent Claim
29 words
The method according to claim 15, comprising: controlling the height of the protrusions by controlling the amount of crystalline phase of the glass-ceramic substrate under about 50% by volume.
Claim 19
Dependent Claim
28 words
The method according to claim 15, comprising controlling the height of the protrusions by further controlling the density of the glass-ceramic substrate to less than about 2.44 g/cc.
Claim 20
Dependent Claim
28 words
The method according to claim 17, comprising controlling the height of the protrusions by further controlling the density of the glass-ceramic substrate to less than about 2.4255 g/cc.
Claim 21
Dependent Claim
51 words
The method according to claim 15, comprising controlling the amount of the crystalline phase of the glass-ceramic substrate by: preparing a glass substrate; and heating the glass substrate under at a controlled temperature for a controlled period of time to form the glass-ceramic substrate having a controlled amount of crystalline phase.
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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) | 2001-12-28 | 2002-06-29 | 2002-12-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-12-28 | 2006-06-29 | 2006-12-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-12-28 | 2010-06-29 | 2010-12-29 | $7700.00 | Window Closed / Lapsed |