US4400221A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fabrication of gallium arsenide-germanium heteroface junction device
Assignee: United States Department of the Air Force
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Filing: 1982-10-26
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Granted: 1983-08-23
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Expires: 2002-10-26
Abstract
Abstract Doping with one of the group Ia elements Li, Na or K near the heteroface junction produced P+ conductivity in the gallium arsenide and N+ conductivity in the germanium. The device can be used, for example, as a dual bandgap solar cell. The fabrication includes implanting the group Ia dopant in a Ge wafer. This dopant diffuses into the GaAs when it is subsequently deposited on the Ge.
Inventors
- 👤 W. Patrick Rahilly
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 16:17
CPC Classifications
H; H10; H10F; H10F10/00; H10F10/10; H10F10/14; H10F10/142; H10D; H10D62/00; H10D62/80; H10D62/82; H10D62/83; H10D62/834; H10D62/85; H10D62/854; H10F10/16; H10F10/164; H10F77/00; H10F77/10; H10F77/12; H10F77/122; H10F77/1223; H10F77/124; H10F77/1243; H10P; H10P32/00; H10P32/10; H10P32/15; Y; Y02; Y02E; Y02E10/00; Y02E10/50; Y02E10/544; Y10; Y10S; Y10S148/00; Y10S148/084; Y10S438/00; Y10S438/933
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
121 words
The method of forming a semiconductor device comprising the steps: a. starting with a germanium wafer having a given type of conductivity; b. doping a region adjacent one surface of said wafer with a group Ia dopant selected from lithium, sodium and potassium; c. growing a layer of a III-V compound including gallium and arsenic on said one surface during which said group Ia dopant diffuses into the growing layer, the growing layer being doped for a given type of conductivity; whereby a heteroface junction is formed at said one surface with the regions adjacent thereto having N+ conductivity in the III-V compound, a lower junction is formed in the germanium, and an upper junction is formed in the III-V compound.
Claim 2
Independent Claim
121 words
The method of forming a semiconductor device comprising the steps: a. starting with a germanium wafer having a given type of conductivity; b. doping a region adjacent one surface of said wafer with a group Ia dopant selected from lithium, sodium and potassium; c. growing a layer of a III-V compound including gallium and arsenic on said one surface during which said group Ia dopant diffuses into the growing layer, the growing layer being doped for a given type of conductivity; whereby a heteroface junction is formed at said one surface with the regions adjacent thereto having N+ conductivity in the III-V compound, a lower junction is formed in the germanium, and an upper junction is formed in the III-V compound.
Claim 3
Dependent Claim
25 words
The method according to claim 1, wherein step (b) comprises ion implantation of the group Ia dopant followed by annealing of the ion implant damage.
Claim 4
Dependent Claim
15 words
The method according to claim 2, wherein the annealing is performed with an electron beam.
Claim 5
Dependent Claim
83 words
The method of forming a solar cell, comprising the steps set forth in claim 1; in which the germanium wafer in step (a) has P-type conductivity; the dopant in step (b) is selected from sodium and potassium; in step (c) said given type of conductivity is N-type; whereby a lower photovoltaic junction is formed in the germanium wafer, and an upper photovoltaic junction is formed in step (c), the two photovoltaic junctions having different bandgap energies, and having the heteroface junction between them.
Claim 6
Dependent Claim
64 words
The method according to claim 4, in which said III-V compound is gallium arsenide, and comprising the further steps of forming a high bandgap aluminum gallium arsenide window on the upper surface of the gallium arsenide layer, forming metallic contacts on said window and also on the lower surface of the germanium wafer, and forming an antireflective coating over said window and its contact.
Claim 7
Dependent Claim
25 words
The method according to claim 5, wherein step (b) comprises ion implantation of the group Ia dopant followed by annealing of the ion implant damage.
Claim 8
Dependent Claim
15 words
The method according to claim 6, wherein the annealing is performed with an electron beam.
Claim 9
Dependent Claim
17 words
The method according to claim 7, wherein step (c) comprises chemical vapor deposition of the III-V compound.
Claim 10
Dependent Claim
43 words
The method according to claim 1, in which the given type of conductivity of the germanium wafer in step (a) is selected from P-type, N-type and intrinsic; and the given type of conductivity in step (c) is selected from P-type, N-type and intrinsic.
Claim 11
Dependent Claim
68 words
The method according to claim 9, in which the III-V layer grown in step (c) has an inner region with said P+ conductivity and an outer region with said upper junction between them; wherein the III-V compound in the inner region is selected from gallium arsenide and aluminum gallium arsenide; and wherein the III-V compound in the outer region is selected from gallium arsenide and aluminum gallium arsenide.
Claim 12
Dependent Claim
17 words
The method according to claim 10, wherein step (c) comprises chemical vapor deposition of the III-V compound.
Claim 13
Dependent Claim
25 words
The method according to claim 11, wherein step (b) comprises ion implantation of the group Ia dopant followed by annealing of the ion implant damage.
Claim 14
Dependent Claim
15 words
The method according to claim 12, wherein the annealing is performed with an electron beam.
Claim 15
Dependent Claim
17 words
The method according to claim 1, wherein step (c) comprises chemical vapor deposition of the III-V compound.
Claim 16
Dependent Claim
25 words
The method according to claim 14, wherein step (b) comprises ion implantation of the group Ia dopant followed by annealing of the ion implant damage.
Claim 17
Dependent Claim
15 words
The method according to claim 15, wherein the annealing is performed with an electron beam.
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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) | 1986-08-22 | 1987-02-21 | 1987-08-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-08-22 | 1991-02-21 | 1991-08-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-08-22 | 1995-02-21 | 1995-08-23 | $7700.00 | Window Closed / Lapsed |