US4267014A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Semiconductor encapsulant for annealing ion-implanted GaAs
Assignee: United States Department of the Navy
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Filing: 1980-02-29
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Granted: 1981-05-12
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Expires: 2000-02-29
Abstract
Abstract A method for protecting an ion-implanted substrate during the annealing process by covering the ion-implanted layer with a suitable encapsulant. A thin layer of ions are implanted into a GaAs substrate. A protective layer of germanium, amorphous GaAs, doped GaAs, or GaAlAs is applied over the implanted layer and on the periphery of the ion-implanted GaAs substrate. The composite is annealed at a temperature which is adequate for the lattice to recover from the ion-implantation-induced damage. The protective layer is removed subsequent to the anneal step, without any damage to the ion-implanted layer.
Inventors
- 👤 John E. Davey
- 👤 Aristos Christou
- 👤 Harry B. Dietrich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 06:55
CPC Classifications
H; H10; H10P; H10P30/00; H10P30/20; H10P30/21; H10P30/202; H10P30/206; H10P30/28; H10P95/00; H10P95/90; H10P95/904; Y; Y10; Y10S; Y10S438/00; Y10S438/902
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
76 words
A method of forming an ion-implanted GaAs device which comprises: implanting ions into one surface of a GaAs substrate, vacuum-depositing onto said ion-implanted surface an encapsulant selected from the group consisting of germanium, gallium-arsenide, and gallium-aluminum-arsenide, annealing said encapsulated, ion-implanted GaAs substrate to remove any ion implantation damage, subsequent to annealing said encapsulated ion-implanted GaAs substrate, selective-chemical-etching said encapsulant to remove said encapsulant from said ion-implanted GaAs substrate without any damage to said ion-implanted GaAs substrate.
Claim 2
Independent Claim
76 words
A method of forming an ion-implanted GaAs device which comprises: implanting ions into one surface of a GaAs substrate, vacuum-depositing onto said ion-implanted surface an encapsulant selected from the group consisting of germanium, gallium-arsenide, and gallium-aluminum-arsenide, annealing said encapsulated, ion-implanted GaAs substrate to remove any ion implantation damage, subsequent to annealing said encapsulated ion-implanted GaAs substrate, selective-chemical-etching said encapsulant to remove said encapsulant from said ion-implanted GaAs substrate without any damage to said ion-implanted GaAs substrate.
Claim 3
Dependent Claim
13 words
A method as claimed in claim 1 in which: said encapsulant is germanium.
Claim 4
Dependent Claim
14 words
A method as claimed in claim 1 wherein: said encapsulant is amorphous gallium arsenide.
Claim 5
Dependent Claim
15 words
A method as claimed in claim 3 wherein: said encapsulant is a layer of gallium-aluminum-arsenide.
Claim 6
Dependent Claim
21 words
A method as claimed in claim 1 wherein: said encapsulant is deposited uniformly to a thickness of about 3×10 3 A.
Claim 7
Dependent Claim
19 words
A method as claimed in claim 5 wherein: said encapsulant is n-type GaAs and said ion-implanted layer is p-type.
Claim 8
Dependent Claim
19 words
A method as claimed in claim 5 wherein: said encapsulant is p-type GaAs, and said ion-implanted layer is n-type.
Claim 9
Dependent Claim
46 words
A method as claimed in claim 5 wherein: said ions are implanted to a dosage of about 5×10 18 ions/cm 3 and, said encapsulant is vacuum-deposited at a temperature of from 450° C. to about 500° C. at a vacuum pressure of about 1×10 -9 Torr.
Claim 10
Dependent Claim
39 words
A method as claimed in claim 8 wherein: said encapsulated ion-implanted GaAs is annealed at a temperature of from about 450° C. to about 850 ° C. for about one hour depending upon the specific dopant and encapsulant used.
Claim 11
Independent Claim
77 words
A method of forming an ion-implanted GaAs device which comprises; implanting ions into one surface of a semiconductive crystalline substrate, vacuum-depositing onto said ion-implanted surface an encapsulant which is lattice-matched and thermally matched to the substrate material; annealing said encapsulated, ion-implanted GaAs substrate to remove any ion implantation damage, subsequent to annealing said encapsulated ion-implanted GaAs substrate, selective-chemical-etching said encapsulant to remove said encapsulant from said ion-implanted GaAs substrate without any damage to said ion-implanted GaAs substrate.
Claim 12
Independent Claim
77 words
A method of forming an ion-implanted GaAs device which comprises; implanting ions into one surface of a semiconductive crystalline substrate, vacuum-depositing onto said ion-implanted surface an encapsulant which is lattice-matched and thermally matched to the substrate material; annealing said encapsulated, ion-implanted GaAs substrate to remove any ion implantation damage, subsequent to annealing said encapsulated ion-implanted GaAs substrate, selective-chemical-etching said encapsulant to remove said encapsulant from said ion-implanted GaAs substrate without any damage to said ion-implanted GaAs substrate.
Claim 13
Dependent Claim
15 words
A method as set forth in claim 10, wherein: said substrate is formed from GaAs.
References Cited (Backward Citations)
US4033788A
Cited
US4058413A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-05-11 | 1984-11-10 | 1985-05-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-05-11 | 1988-11-10 | 1989-05-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-05-11 | 1992-11-10 | 1993-05-12 | $7700.00 | Window Closed / Lapsed |