US4902642A
Expired / Lapsed
US
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Epitaxial process for silicon on insulator structure
Assignee: Texas Instruments Inc
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Filing: 1988-08-24
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Granted: 1990-02-20
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Expires: 2008-08-24
Abstract
Abstract The present invention provides products and methods of forming an epitaxial silicon layer on an implanted buried insulator silicon on insulator structure (10). A silicon film (16) is pre-treated to remove residual oxide and surface damage layers, but in such a way as to not damage the silicon film (16) or insulating layer (14) below the silicon film (16). A layer of amorphous silicon (18) is formed on the silicon film (16) in processes to avoid formation of polycrystalline silicon, and also to avoid damage to the silicon film (16). The layer of amorphous silicon (18) is annealed to form an epitaxial layer of single crystalline silicon (20).
Inventors
- 👤 Bor-Yen Mao
- 👤 Richard L. Yeakley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 23:14
CPC Classifications
H; H10; H10P; H10P14/00; H10P14/20; H10P14/29; H10P14/2901; H10P14/2902; H10P14/2905; H10P14/22; H10P14/24; H10P14/32; H10P14/3202; H10P14/3238; H10P14/34; H10P14/3402; H10P14/3404; H10P14/3411; H10P14/36; H10P14/3602; Y; Y10; Y10S; Y10S148/00; Y10S148/071; Y10S148/152; Y10S148/154
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
84 words
A method of forming an epitaxial silicon layer on a single crystalline silicon film which is on an insulating layer, said method comprising: implanting oxygen into the surface of a silicon material; annealing the silicon material so that a single crystalline film is formed over a layer of silicon dioxide; forming a layer of amorphous silicon on said single crystalline silicon film; and annealing all of said layer of amorphous silicon at substantially the same time to form a layer of single crystalline silicon.
Claim 2
Independent Claim
84 words
A method of forming an epitaxial silicon layer on a single crystalline silicon film which is on an insulating layer, said method comprising: implanting oxygen into the surface of a silicon material; annealing the silicon material so that a single crystalline film is formed over a layer of silicon dioxide; forming a layer of amorphous silicon on said single crystalline silicon film; and annealing all of said layer of amorphous silicon at substantially the same time to form a layer of single crystalline silicon.
Claim 3
Dependent Claim
21 words
The method of claim 1, wherein said layer of amorphous silicon is formed by low pressure chemical vapor deposition of silicon.
Claim 4
Dependent Claim
19 words
The method of claim 1, wherein said layer of amorphous silicon is formed by a molecular beam deposition process.
Claim 5
Dependent Claim
24 words
The method of claim 2, wherein said low pressure chemical vapor deposition process is carried out at a pressure of less than 250 millitorrs.
Claim 6
Dependent Claim
21 words
The method of claim 2, wherein said low pressure chemical vapor deposition process is carried out at less than 650° C.
Claim 7
Dependent Claim
37 words
The method of claim 1, further comprising, prior to said step of forming a layer of amorphous silicon on said silicon film, the step of: treating said silicon film to remove residual oxide from said silicon film.
Claim 8
Dependent Claim
23 words
The method of claim 6, wherein said step of treating said silicon film comprises: subjecting said film to a hydrofluoric acid wet etch.
Claim 9
Dependent Claim
18 words
The method of claim 6, wherein said step of treating said silicon film comprises: heating said silicon film.
Claim 10
Dependent Claim
18 words
The method of claim 8, wherein said heating of said silicon film is to temperatures below 725° C.
Claim 11
Dependent Claim
23 words
The method of claim 6, wherein said step of treating said silicon film comprises: subjecting said silicon film to a reduced pressure environment.
Claim 12
Dependent Claim
19 words
The method of claim 10, wherein said reduced pressure environment comprises a pressure of less than 10 -5 torr.
Claim 13
Dependent Claim
28 words
The method of claim 6, wherein said step of annealing said layer of amorphous silicon comprises heating said layer of amorphous silicon to a temperature above 1000° C.
Claim 14
Dependent Claim
28 words
The method of claim 6, wherein said step of annealing said layer of amorphous silicon comprises heating said layer of amorphous silicon to a temperature above 1200° C.
Claim 15
Dependent Claim
37 words
The method of claim 6, wherein said step of treating said silicon film comprises: subjecting said silicon film to an environment of from 550° C. to 700° C. at a pressure of less than 10 -7 torr.
References Cited (Backward Citations)
US4046618A
Cited
US4357179A
Cited
US4371421A
Cited
US4448632A
Cited
US4498226A
Cited
US4498951A
Cited
US4565599A
Cited
US4565584A
Cited
US4487635A
Cited
US4604159A
Cited
US4596604A
Cited
US4584025A
Cited
US4579609A
Cited
US4692994A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1993-02-19 | 1993-08-21 | 1994-02-20 | $2000.00 | Window Closed / Lapsed |
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