Patent US4360393A successfully refreshed from Google Patents.
US4360393A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Vapor deposition of H3 PO4 and formation of thin phosphorus layer on silicon substrates
Assignee: BP Solar International LLC
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Filing: 1980-12-18
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Granted: 1982-11-23
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Expires: 2000-12-18
Abstract
Abstract Provision for a source of phosphorus dopant on a silicon wafer, for the subsequent formation of an electrical p-n junction, by the vapor deposition, at atmospheric pressure, of phosphoric acid to form an essentially continuous film on a silicon wafer, said wafer being at room temperature, and the firing of said film to form a phosphorus oxide-silicate-glass layer which will not interfere with any antireflective layer deposited thereon.
Inventors
- 👤 Timothy D. Koval
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 05:01
CPC Classifications
H; H10; H10P; H10P14/00; H10P14/60; H10P14/69; H10P14/692; H10P14/6921; H10P14/6922; H10P14/6923; C; C30; C30B; C30B31/00; C30B31/02; H10P14/63; H10P14/6326; H10P14/6328; H10P14/6334
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
74 words
A method of forming a phosphorus/silicon glass layer on the surface of a silicon substrate, comprising (a) providing liquid phosphoric acid, (b) vaporizing said phosphoric acid to a gasous form, (c) condensing said gaseous phosphoric acid on the surface of said silicon substrate to form a film on said substrate, and (d) heating said substrate and said film to form a phosphorus/silicon glass layer on said substrate and a P-N junction in said substrate.
Claim 2
Independent Claim
74 words
A method of forming a phosphorus/silicon glass layer on the surface of a silicon substrate, comprising (a) providing liquid phosphoric acid, (b) vaporizing said phosphoric acid to a gasous form, (c) condensing said gaseous phosphoric acid on the surface of said silicon substrate to form a film on said substrate, and (d) heating said substrate and said film to form a phosphorus/silicon glass layer on said substrate and a P-N junction in said substrate.
Claim 3
Dependent Claim
38 words
A method as claimed in claim 1, in which said gaseous phosphoric acid is formed by spraying said liquid phosphoric acid through a tube heated to a temperature in the range of about 400° C. to 800° C.
Claim 4
Dependent Claim
19 words
A method as claimed in claim 2, in which said gaseous phosphoric acid is carried by an inert gas.
Claim 5
Dependent Claim
24 words
A method as claimed in claim 3, in which said inert gas is selected from the group consisting of nitrogen, argon, helium and neon.
Claim 6
Dependent Claim
24 words
A method as claimed in claim 1, in which said gaseous phosphoric acid is maintained at about atmospheric pressure during condensation on said substrate.
Claim 7
Dependent Claim
35 words
A method as claimed in claim 1, in which said substrate and said film are heated to a temperature in the range of about 800° C. to about 900° C. to form said glass layer.
Claim 8
Dependent Claim
23 words
A method as claimed in claim 1, in which said phosphorus/silicon glass layer has a thickness of about 90° A to 200° A.
Claim 9
Dependent Claim
21 words
A method as claimed in claim 1, in which said liquid phosphoric acid is vaporized by spraying it with an atomizer.
Claim 10
Dependent Claim
25 words
A method as claimed in claim 8, in which said liquid phosphoric acid is sprayed through a zone heated to about 400° to 800° C.
Claim 11
Dependent Claim
25 words
A method as claimed in claim 1, in which said silicon substrate is subjected to gaseous phosphoric acid for about 45 seconds to 2 minutes.
References Cited (Backward Citations)
US3173802A
Cited
US4206026A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-11-22 | 1986-05-24 | 1986-11-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-11-22 | 1990-05-24 | 1990-11-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-11-22 | 1994-05-24 | 1994-11-23 | $7700.00 | Window Closed / Lapsed |