Patent US3289361A successfully refreshed from Google Patents.
Patent US5061653A successfully refreshed from Google Patents.
US5061653A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Trench isolation process
Assignee: Texas Instruments Inc
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Filing: 1990-10-30
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Granted: 1991-10-29
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Expires: 2010-10-30
Abstract
Abstract The disclosure relates to the article and a method of forming a field oxide which extends over an isolation trench and the adjacent substrate wherein a portion of the trench insulating sidewall at the top region thereof is removed and replaced by polysilicon. The exposed silicon on the substrate and adjacent polysilicon are than oxidized to form the field oxide which is continuous, disposed above and contacts the remaining sidewall insulator in the trench.
Inventors
- 👤 Clarence W. Teng
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 22:31
CPC Classifications
H; H10; H10W; H10W10/00; H10W10/01; H10W10/041; H10W10/40; Y; Y10; Y10S; Y10S148/00; Y10S148/05
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
101 words
A method of forming a semiconductor device, comprising the steps of: (a) providing a silicon substrate having a trench filled with polysilicon and having insulating sidewalls and bottom; (b) forming a layer of polysilicon extending over said insulating sidewalls in said trench and contacting said substrate, and burying said insulating sidewalls in said trench with polysilicon; and (c) oxidizing said polysilicon at the upper surface of said trench and a portion of the upper surface of said substrate exterior of said trench and extending to said trench to form a continuous field oxide over said trench which extends over said substrate.
Claim 2
Independent Claim
101 words
A method of forming a semiconductor device, comprising the steps of: (a) providing a silicon substrate having a trench filled with polysilicon and having insulating sidewalls and bottom; (b) forming a layer of polysilicon extending over said insulating sidewalls in said trench and contacting said substrate, and burying said insulating sidewalls in said trench with polysilicon; and (c) oxidizing said polysilicon at the upper surface of said trench and a portion of the upper surface of said substrate exterior of said trench and extending to said trench to form a continuous field oxide over said trench which extends over said substrate.
Claim 3
Dependent Claim
23 words
A method as set forth in claim 1, wherein said polysilicon formed in step (b) extends over said substrate exterior to said trench.
Claim 4
Dependent Claim
45 words
A method as set forth in claim 2, wherein step (b) includes removing a portion of said insulating sidewall in the region thereof extending from the upper edge of said trench toward the interior thereof and filling the region of removed sidewall with said polysilicon.
Claim 5
Dependent Claim
57 words
A method as set forth in claim 3 wherein, in step (a), an oxide layer is provided over said substrate, said step of removing said portions of said sidewall includes removal of a portion of said oxide layer and said step of filling said region of removed sidewall also includes filling said region of removed oxide layer.
Claim 6
Dependent Claim
22 words
A method as set forth in claim 4 wherein a silicon nitride layer is provided over said oxide layer in step (a).
Claim 7
Dependent Claim
44 words
A method as set forth in claim 1, wherein step (b) includes removing a portion of said insulating sidewall in the region thereof extending from the upper edge of said trench toward the interior and filling the region of removed sidewall with said polysilicon.
Claim 8
Dependent Claim
57 words
A method as set forth in claim 6 wherein, in step (a), an oxide layer is provided over said substrate, said step of removing said portions of said sidewall includes removal of a portion of said oxide layer and said step of filling said region of removed sidewall also include filling said region of removed oxide layer.
Claim 9
Dependent Claim
22 words
A method as set forth in claim 7 wherein a silicon nitride layer is provided over said oxide layer in step (a).
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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) | 1994-10-28 | 1995-04-29 | 1995-10-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-10-28 | 1999-04-29 | 1999-10-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-10-28 | 2003-04-29 | 2003-10-29 | $7700.00 | Window Closed / Lapsed |