Patent US4276432A successfully refreshed from Google Patents.
Patent US4983226A successfully refreshed from Google Patents.
US4983226A
Expired / Lapsed
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Defect free trench isolation devices and method of fabrication
Assignee: Texas Instruments Inc
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Filing: 1990-03-15
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Granted: 1991-01-08
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Expires: 2010-03-15
Abstract
Abstract The specification discloses an isolation trench (36) formed in a semiconductor body. A stress relief layer (38) of oxide is formed on the interior walls of the trench (36), the layer (38) being sufficiently thin to prevent stressing of the lower corners of the trench (36). A masking layer (40) of nitride is formed over the layer (38). An isolation body (42) of oxide or polysilicon then refills the remainder of the trench and a cap oxide (43) and layer (44) of field oxide is formed over the semiconductor body and the filled trench.
Inventors
- 👤 William R. Hunter
- 👤 Christopher Slawinski
- 👤 Clarence W. Teng
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 09:47
CPC Classifications
H; H10; H10W; H10W10/00; H10W10/01; H10W10/011; H10W10/012; H10W10/014; H10W10/041; H10W10/10; H10W10/13; H10W10/17; H10W10/40; Y; Y10; Y10S; Y10S148/00; Y10S148/05
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
99 words
An isolation trench in a semiconductor body comprising: a trench formed in the semiconductor body; a layer of insulating material on the interior walls of said trench, said layer of insulating material being sufficiently thin to prevent stressing of the corners of said trench; a masking layer formed adjacent said layer of insulating material; a dialectric layer of insulating material formed adjacent said masking layer; a second masking layer adjacent said dielectric layer; and an isolation body filling the remaining area of said trench; and a layer of field oxide formed over the semiconductor body and the filled trench.
Claim 2
Dependent Claim
99 words
An isolation trench in a semiconductor body comprising: a trench formed in the semiconductor body; a layer of insulating material on the interior walls of said trench, said layer of insulating material being sufficiently thin to prevent stressing of the corners of said trench; a masking layer formed adjacent said layer of insulating material; a dialectric layer of insulating material formed adjacent said masking layer; a second masking layer adjacent said dielectric layer; and an isolation body filling the remaining area of said trench; and a layer of field oxide formed over the semiconductor body and the filled trench.
Claim 3
Dependent Claim
13 words
The isolation trench of claim 1 wherein said isolation body comprises silicon oxide.
Claim 4
Dependent Claim
12 words
The isolation trench of claim 1 wherein said isolation body comprises polysilicon.
Claim 5
Dependent Claim
15 words
The isolation trench of claim 1 wherein said layer of insulating material comprises silicon oxide.
Claim 6
Dependent Claim
12 words
The isolation trench of claim 1 wherein said masking layer comprises nitride.
Claim 7
Dependent Claim
24 words
The isolation trench of claim 1 wherein said layer of insulating material has a thickness in the range of 200 Å to 450 Å.
Claim 8
Dependent Claim
20 words
The isolation trench of claim 1 wherein said masking layer has a thickness of from 300 Å to 600 Å.
Claim 9
Dependent Claim
18 words
The isolation trench of claim 1 wherein said field oxide is formed at a temperature above 1000° C.
References Cited (Backward Citations)
US3500139A
Cited
US4079506A
Cited
US4396460A
Cited
US4563227A
Cited
JPS58153349A
Cited
JPS58200575A
Cited
US4582565A
Cited
US4528047A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-01-07 | 1994-07-09 | 1995-01-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-01-07 | 1998-07-09 | 1999-01-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-01-07 | 2002-07-09 | 2003-01-08 | $7700.00 | Window Closed / Lapsed |