Patent US4564720A successfully refreshed from Google Patents.
US4564720A
Expired / Lapsed
US
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Pure silver ohmic contacts to N- and P- type gallium arsenide materials
Assignee: United States Department of Energy
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Filing: 1983-05-13
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Granted: 1986-01-14
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Expires: 2003-05-13
Abstract
Abstract Disclosed is an improved process for manufacturing gallium arsenide semiconductor devices having as its components an n-type gallium arsenide substrate layer and a p-type gallium arsenide diffused layer. The improved process comprises forming a pure silver ohmic contact to both the diffused layer and the substrate layer, wherein the n-type layer comprises a substantially low doping carrier concentration.
Inventors
- 👤 Stephen J. Hogan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 21:10
CPC Classifications
H; H10; H10F; H10F77/00; H10F77/20; H10F77/206; H10F77/211; H10D; H10D62/00; H10D62/80; H10D62/85; H10D64/00; H10D64/01; H10D64/011; H10D64/0116; H10D64/60; H10D64/62; Y; Y02; Y02E; Y02E10/00; Y02E10/50; Y10; Y10S; Y10S148/00; Y10S148/14
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
90 words
A process for manufacturing gallium arsenide devices having as its components an n-type gallium arsenide substrate layer and a p-type diffused layer, wherein the improvement comprises: depositing by vacuum evaporation a pure silver contact on both the diffused layer and the substrate layer; treating the deposited pure silver contacts with heat to effect ohmicity; and wherein the n-type substrate layer comprises a doping carrier concentration of less than 1×10 18 cm -3 and the p-type diffused layer comprises a doping carrier concentration of less than 6×10 18 cm -3 .
Claim 2
Dependent Claim
90 words
A process for manufacturing gallium arsenide devices having as its components an n-type gallium arsenide substrate layer and a p-type diffused layer, wherein the improvement comprises: depositing by vacuum evaporation a pure silver contact on both the diffused layer and the substrate layer; treating the deposited pure silver contacts with heat to effect ohmicity; and wherein the n-type substrate layer comprises a doping carrier concentration of less than 1×10 18 cm -3 and the p-type diffused layer comprises a doping carrier concentration of less than 6×10 18 cm -3 .
Claim 3
Dependent Claim
29 words
A method as recited in claim 1, wherein said silver contacts are treated with heat a temperature of about 450° C. for about 10 minutes in a forming gas.
Claim 4
Dependent Claim
12 words
A gallium arsenide solar cell produced by the method of claim 1.
Claim 5
Dependent Claim
78 words
A gallium arsenide semiconductor device comprising: an n-type substrate layer, said n-type substrate layer being doped to doping carrier concentrations of less than 1×10 18 cm -3 ; a p-type diffused layer doped to a doping carrier concentration of less than 6×10 18 cm -3 ; and a pure silver ohmic contact system, and wherein said n-type layer includes a first pure silver ohmic contact thereon and said p-type layer includes a second pure silver ohmic contact thereon.
Claim 6
Dependent Claim
78 words
A gallium arsenide semiconductor device comprising: an n-type substrate layer, said n-type substrate layer being doped to doping carrier concentrations of less than 1×10 18 cm -3 ; a p-type diffused layer doped to a doping carrier concentration of less than 6×10 18 cm -3 ; and a pure silver ohmic contact system, and wherein said n-type layer includes a first pure silver ohmic contact thereon and said p-type layer includes a second pure silver ohmic contact thereon.
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) | 1989-01-13 | 1989-07-15 | 1990-01-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-01-13 | 1993-07-15 | 1994-01-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-01-13 | 1997-07-15 | 1998-01-14 | $7700.00 | Window Closed / Lapsed |