Patent US3971870A successfully refreshed from Google Patents.
US3971870A
Expired / Lapsed
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Semiconductor device material
Assignee: Semi-Elements Inc
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Filing: 1974-01-24
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Granted: 1976-07-27
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Expires: 1994-01-24
Abstract
Abstract This patent discloses a method for making junction-type semiconductor devices in which dopant is introduced into a wafer from a prefabricated source film.
Inventors
- 👤 Ralph W. Christensen
- 👤 Everett C. Smith
- 👤 George Tibol
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 18:53
CPC Classifications
H; H10; H10P; H10P32/00; H10P32/10; H10P32/17; H10P32/171; H10P32/12; H10P32/14; H10P32/1408; H10P32/141; H10P32/19; Y; Y10; Y10T; Y10T428/00; Y10T428/26; Y10T428/263; Y10T428/264; Y10T428/265
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
85 words
A self-supporting flexible film having a thickness of about 0.0005 to 0.02 inches consisting essentially of from 90 to 97% of a dopant component consisting essentially of a finely divided semiconductor dopant material selected from the group consisting of phosphorous pentoxide, arsenic, antimony, iron, cobalt, boron nitride, boric acid, indium, methyl borate and gallium, said dopant component homogeneously admixed with from 3 to 10% of a volatile organic binder selected from the group consisting of cyanoethylated cellulose, methyl cellulose, polyvinyl alcohol, starch and vinyl butyral.
Claim 2
Dependent Claim
85 words
A self-supporting flexible film having a thickness of about 0.0005 to 0.02 inches consisting essentially of from 90 to 97% of a dopant component consisting essentially of a finely divided semiconductor dopant material selected from the group consisting of phosphorous pentoxide, arsenic, antimony, iron, cobalt, boron nitride, boric acid, indium, methyl borate and gallium, said dopant component homogeneously admixed with from 3 to 10% of a volatile organic binder selected from the group consisting of cyanoethylated cellulose, methyl cellulose, polyvinyl alcohol, starch and vinyl butyral.
Claim 3
Dependent Claim
43 words
The film of claim 1 wherein the dopant component contains from 1 to 5% by weight, of the total weight of the film, of the dopant material and from 90 to 98% by weight of the total weight of the film, of alumina.
References Cited (Backward Citations)
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US2375847A
Cited
US2993787A
Cited
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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) | 1979-07-27 | 1980-01-26 | 1980-07-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-07-27 | 1984-01-26 | 1984-07-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-07-27 | 1988-01-26 | 1988-07-27 | $7700.00 | Window Closed / Lapsed |