Patent US5629531A successfully refreshed from Google Patents.
US5629531A
Expired / Lapsed
US
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Method of obtaining high quality silicon dioxide passivation on silicon carbide and resulting passivated structures
Assignee: Wolfspeed Inc
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Filing: 1994-12-09
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Granted: 1997-05-13
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Expires: 2014-12-09
Abstract
Abstract A method of obtaining high quality passivation layers on silicon carbide surfaces by oxidizing a sacrificial layer of a silicon-containing material on a silicon carbide portion of a device structure to substantially consume the sacrificial layer to produce an oxide passivation layer on the silicon carbide portion that is substantially free of dopants that would otherwise degrade the electrical integrity of the oxide layer.
Inventors
- 👤 John W. Palmour
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 02:48
CPC Classifications
H; H10; H10D; H10D62/00; H10D62/80; H10D62/83; H10D62/832; H10D62/8325; H10D12/00; H10D12/01; H10D12/031; H10D64/00; H10D64/01; H10D64/013; H10D64/01366; H10D64/60; H10D64/66; H10D64/68; H10D8/00; H10D8/01; H10D8/051; H10W; H10W74/00; H10W74/10; H10W74/131; H10W74/137; H10D30/00; H10D30/60; Y; Y10; Y10S; Y10S148/00; Y10S148/148; Y10S438/00; Y10S438/931
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
58 words
A silicon carbide-based device structure having passivation areas that have substantially fewer impurities than the amounts normally associated with oxides grown on doped silicon carbide, said structure comprising: a silicon carbide portion; and a thermally-grown oxidation layer upon said silicon carbide portion, said oxidation layer having an aluminum dopant concentration of 3E17 (3×10.sup.∫ cm -3 ) or less.
Claim 2
Dependent Claim
58 words
A silicon carbide-based device structure having passivation areas that have substantially fewer impurities than the amounts normally associated with oxides grown on doped silicon carbide, said structure comprising: a silicon carbide portion; and a thermally-grown oxidation layer upon said silicon carbide portion, said oxidation layer having an aluminum dopant concentration of 3E17 (3×10.sup.∫ cm -3 ) or less.
Claim 3
Dependent Claim
33 words
A device structure according to claim 1 wherein said silicon carbide portion is selected from the group consisting of: a substrate, epitaxial layers, mesa sidewalls, implanted wells, diffused wells, and any combinations thereof.
Claim 4
Dependent Claim
25 words
A device structure according to claim 1 wherein said oxidation layer is substantially free of carbon-oxygen by-products typically associated with thermal oxidation of silicon carbide.
References Cited (Backward Citations)
US3911168A
Cited
DE3434727A1
Cited
US5272107A
Cited
US4757028A
Cited
US5087576A
Cited
US4866005A
Cited
US4912063A
Cited
US4912064A
Cited
US4865685A
Cited
US4994413A
Cited
EP0363944A1
Cited
US5061972A
Cited
DE4009837A1
Cited
US5135885A
Cited
JPH039534A
Cited
US5216264A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-05-12 | 2000-11-11 | 2001-05-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-05-12 | 2004-11-11 | 2005-05-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-05-12 | 2008-11-11 | 2009-05-13 | $7700.00 | Window Closed / Lapsed |