Patent US4515642A successfully refreshed from Google Patents.
US4515642A
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US
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Method of forming deep aluminum doped silicon by implanting Al and Si ions through alumina layer and device formed thereby
Assignee: Toshiba Corp
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Filing: 1983-08-22
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Granted: 1985-05-07
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Expires: 2003-08-22
Abstract
Abstract In a method of producing a semiconductor device, an alumina layer is formed directly on a principal surface of a silicon substrate; aluminum and silicon are ion-implanted through the alumina layer into said substrate; and the substrate is thereafter annealed. The ion-implanted silicon yields better crystalline structure and increases the solid solubility limit of aluminum.
Inventors
- 👤 Takashi Ajima
- 👤 Jiro Ohshima
- 👤 Yutaka Koshino
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 12:13
CPC Classifications
H; H10; H10P; H10P14/00; H10P14/60; H10P14/69; H10P14/692; H10P14/6938; H10P14/6939; H10P14/69391; H10P14/63; H10P14/6326; H10P14/6328; H10P30/00; H10P30/20; H10P30/202; H10P30/204; H10P30/208; H10P30/21; H10P30/212; H10P30/28; H10P32/00
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
54 words
A method of producing a semiconductor device comprising the steps of: forming an alumina layer directly on a principal surface of a silicon substrate; ion-implanting aluminum through said alumina layer into said substrate; ion-implanting silicon through said alumina layer into said substrate; and annealing said substrate into which aluminum and silicon have been ion-implanted.
Claim 2
Independent Claim
54 words
A method of producing a semiconductor device comprising the steps of: forming an alumina layer directly on a principal surface of a silicon substrate; ion-implanting aluminum through said alumina layer into said substrate; ion-implanting silicon through said alumina layer into said substrate; and annealing said substrate into which aluminum and silicon have been ion-implanted.
Claim 3
Dependent Claim
23 words
A method of claim 1, wherein the acceleration voltage used in the ion-implantation of aluminum and silicon is not more than 150 keV.
Claim 4
Dependent Claim
39 words
A method of claim 1, wherein the acceleration voltage used for the ion-implantation of silicon is about 150 keV and the dosage of silicon by the ion-implantation is within the range of 10 13 -10 16 cm -2 .
Claim 5
Dependent Claim
13 words
A method of claim 1, wherein the annealing comprises open tube diffusion process.
Claim 6
Dependent Claim
19 words
A method of claim 2, wherein the thickness of the alumina layer formed is not more than 1000 Å.
Claim 7
Dependent Claim
25 words
A method of claim 3, wherein the dosage of silicon by the ion-implantation is within the range of 10 14 -10 16 cm -2 .
Claim 8
Dependent Claim
33 words
A method of claim 4, wherein the annealing by the open tube diffusion comprises placing the wafer in a nitrogen gas atmosphere at a temperature of about 1200° C. for about 60 hours.
Claim 9
Dependent Claim
39 words
A method of claim 6, wherein the acceleration voltage used for the ion-implantation of aluminum is about 150 keV and the dosage of aluminum by the ion-implantation is within the range of 5×10 14 -5×10 15 cm -2 .
References Cited (Backward Citations)
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US4466839A
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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) | 1988-05-06 | 1988-11-05 | 1989-05-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-05-06 | 1992-11-05 | 1993-05-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-05-06 | 1996-11-05 | 1997-05-07 | $7700.00 | Window Closed / Lapsed |