Patent EP0230029A2 successfully refreshed from Google Patents.
US4433008A
Expired / Lapsed
US
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Doped-oxide diffusion of phosphorus using borophosphosilicate glass
Assignee: Fairchild Semiconductor Corp
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Filing: 1982-05-11
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Granted: 1984-02-21
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Expires: 2002-05-11
Abstract
Abstract The invention is a method for diffusing phosphorus into the surface of a silicon substrate using borophosphosilicate glass as the phosphorus source.
Inventors
- 👤 George L. Schnable
- 👤 Edward A. James
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 00:49
CPC Classifications
H; H10; H10P; H10P32/00; H10P32/10; H10P32/14; H10P32/1408; H10P32/141; H10P32/17; H10P32/171
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
56 words
A method of diffusing phosphorus into a silicon substrate, said method comprising: depositing directly on a surface of the substrate a layer of a borophosphosilicate glass; and heating the substrate and the layer to a temperature whereby phosphorus diffuses into the silicon and boron is retained in the glass, said temperature being below about 1000° C.
Claim 2
Independent Claim
56 words
A method of diffusing phosphorus into a silicon substrate, said method comprising: depositing directly on a surface of the substrate a layer of a borophosphosilicate glass; and heating the substrate and the layer to a temperature whereby phosphorus diffuses into the silicon and boron is retained in the glass, said temperature being below about 1000° C.
Claim 3
Dependent Claim
17 words
The method of claim 1 wherein the temperature is between about 700° C. and about 950° C.
Claim 4
Dependent Claim
22 words
The method according to claim 1 wherein the borophosphosilicate glass contains less than about 20 weight percent of boron and of phosphorus.
Claim 5
Dependent Claim
24 words
The method of claim 3 wherein the borophosphosilicate glass contains between about 1 and about 10 percent by weight of boron and of phosphorus.
Claim 6
Dependent Claim
22 words
The method of claim 4 wherein the borophosphosilicate glass contains between about 3 and 7 weight percent of boron and of phosphorus.
References Cited (Backward Citations)
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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) | 1987-02-20 | 1987-08-22 | 1988-02-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-02-20 | 1991-08-22 | 1992-02-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-02-20 | 1995-08-22 | 1996-02-21 | $7700.00 | Window Closed / Lapsed |