US4478879A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Screen printed interdigitated back contact solar cell
Assignee: National Aeronautics and Space Administration
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Filing: 1983-02-10
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Granted: 1984-10-23
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Expires: 2003-02-10
Abstract
Abstract Interdigitated back contact solar cells are made by screen printing dopant materials onto the back surface of a semiconductor substrate in a pair of interdigitated patterns. These dopant materials are then diffused into the substrate to form junctions having configurations corresponding to these patterns. Contacts having configurations which match the patterns are then applied over the junctions.
Inventors
- 👤 Cosmo R. Baraona
- 👤 George A. Mazaris
- 👤 An-Ti Chai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 21:25
CPC Classifications
H; H10; H10F; H10F77/00; H10F77/20; H10F77/206; H10F77/211; H10F77/215; H10F71/00; H10F71/121; H10F77/10; H10F77/14; H10F77/148; H10P; H10P32/00; H10P32/10; H10P32/14; H10P32/1408; H10P32/17; H10P32/171; Y; Y02; Y02E; Y02E10/00; Y02E10/50; Y02E10/547; Y02P; Y02P70/00; Y02P70/50
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
212 words
In a method of making an interdigitated back contact solar cell of the type having both a first junction and a second junction adjacent to the nonilluminated back surface of a semiconductor substrate in a pair of interdigitated patterns with a uniform spacing therebetween, the improvement comprising forming an opening having a predetermined area in a first screen, said opening having a configuration corresponding to one of said patterns, positioning said first screen adjacent to said back surface of said substrate, screen printing one type of dopant material onto said back surface of said substrate in said first configuration and diffusing the same into said substrate, forming another opening having another area in a second screen, said other opening having another configuration corresponding to the other of said patterns, the ratio of said predetermined area of the opening in the first screen to said other area of the opening in the second screen being about eight to one, positioning said second screen adjacent to said back surface of said substrate so that said other pattern is uniformly spaced from said one pattern a distance of about one mil, and screen printing an opposite type of dopant material on said back surface in said other configuration and diffusing the same onto said substrate.
Claim 2
Dependent Claim
212 words
In a method of making an interdigitated back contact solar cell of the type having both a first junction and a second junction adjacent to the nonilluminated back surface of a semiconductor substrate in a pair of interdigitated patterns with a uniform spacing therebetween, the improvement comprising forming an opening having a predetermined area in a first screen, said opening having a configuration corresponding to one of said patterns, positioning said first screen adjacent to said back surface of said substrate, screen printing one type of dopant material onto said back surface of said substrate in said first configuration and diffusing the same into said substrate, forming another opening having another area in a second screen, said other opening having another configuration corresponding to the other of said patterns, the ratio of said predetermined area of the opening in the first screen to said other area of the opening in the second screen being about eight to one, positioning said second screen adjacent to said back surface of said substrate so that said other pattern is uniformly spaced from said one pattern a distance of about one mil, and screen printing an opposite type of dopant material on said back surface in said other configuration and diffusing the same onto said substrate.
Claim 3
Dependent Claim
26 words
A method of making an interdigitated back contact solar cell as claimed in claim 1 wherein the dopant materials are screen printed sequentially and diffused sequentially.
Claim 4
Dependent Claim
26 words
A method of making an interdigitated back contact solar cell as claimed in claim 1 wherein the dopant materials are screen printed sequentially and diffused simultaneously.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-10-23 | 1988-04-23 | 1988-10-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-10-23 | 1992-04-23 | 1992-10-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-10-23 | 1996-04-23 | 1996-10-23 | $7700.00 | Window Closed / Lapsed |