Patent US3575050A successfully refreshed from Google Patents.
Patent US4402771A successfully refreshed from Google Patents.
US4402771A
Expired / Lapsed
US
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Substrate for silicon solar cells
Assignee: Westinghouse Electric Corp
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Filing: 1982-03-15
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Granted: 1983-09-06
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Expires: 2002-03-15
Abstract
Abstract A substrate is made for silicon solar cells by heating a sheet of large-grained silicon steel at a temperature of at least about 1300° C. in an atmosphere of hydrogen and tungsten hexafluoride (or hexachloride) at a partial pressure ratio of hydrogen to tungsten hexafluoride of about 3 to about 6 to deposit an epitaxial layer of tungsten on said sheet of silicon steel. Epitaxial silicon can then be deposited in a conventional manner on the layer of epitaxial tungsten.
Inventors
- 👤 Donald E. Thomas
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 21:26
CPC Classifications
C; C30; C30B; C30B29/00; C30B29/02; C30B29/06; C30B25/00; C30B25/02; C30B25/18; H; H10; H10F; H10F71/00; H10F71/121; H10F77/00; H10F77/10; H10F77/16; H10F77/169; H10F77/1692; Y; Y02; Y02E; Y02E10/00; Y02E10/50; Y02E10/547; Y02P; Y02P70/00; Y02P70/50
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
28 words
A method of making a substrate comprising depositing an epitaxial layer of doped silicon on an epitaxial layer of tungsten on a sheet of large grained silicon steel.
Claim 2
Independent Claim
28 words
A method of making a substrate comprising depositing an epitaxial layer of doped silicon on an epitaxial layer of tungsten on a sheet of large grained silicon steel.
Claim 3
Dependent Claim
21 words
A method according to claim 1 including the additional last step of providing a pin junction in said layer of silicon.
Claim 4
Dependent Claim
21 words
A method according to claim 1 including the additional last step of mounting a current collector on said layer of silicon.
Claim 5
Dependent Claim
19 words
A method according to claim 1 wherein said tungsten has a thickness of about 1 to about 20 microns.
Claim 6
Dependent Claim
22 words
A method according to claim 1 wherein the amount of silicon in said steel is about 21/2 to about 5% by weight.
Claim 7
Dependent Claim
18 words
A method according to claim 1 wherein said silicon steel is about 10 to about 15 mils thick.
Claim 8
Dependent Claim
19 words
A method according to claim 1 wherein said layer of tungsten is about 1 to about 10 microns thick.
Claim 9
Dependent Claim
64 words
A method according to claim 1 wherein said epitaxial layer of tungsten on said sheet of silicon steel was made by heating a sheet of large-grained silicon steel to at least about 1300° C. in an atmosphere of hydrogen and either tungsten hexafluoride or tungsten hexachloride at a partial pressure of hydrogen to said tungsten hexafluoride or hexachloride of about 3 to about 6.
Claim 10
Dependent Claim
26 words
A method according to claim 8 wherein the grain size of said silicon steel is at least 10 times the thickness of said layer of silicon.
Claim 11
Dependent Claim
25 words
A method according to claim 8 wherein the total pressure of said hydrogen and tungsten hexafluoride or hexachloride is about 0.05 to about 0.15 torr.
Claim 12
Dependent Claim
11 words
A method according to claim 8 wherein tungsten hexafluoride is used.
References Cited (Backward Citations)
US3911194A
Cited
US3961997A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-09-05 | 1987-03-07 | 1987-09-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-09-05 | 1991-03-07 | 1991-09-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-09-05 | 1995-03-07 | 1995-09-06 | $7700.00 | Window Closed / Lapsed |