US4291327A
Expired / Lapsed
US
⏱️ 0.0 years remaining
MOS Devices
Assignee: AT&T Inc
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Filing: 1980-01-23
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Granted: 1981-09-22
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Expires: 2000-01-23
Abstract
Abstract An oxide layer (16') is formed on a GaAs body (14) by epitaxially growing a layer (12) of Al x Ga 1-x As layer on a major surface (18) of the body and then thermally oxidizing the Al x Ga 1-x As layer for a time period effective to convert it to an oxide. The oxidizing process is essentially self-terminating at the major surface 18. The application of this process to the fabrication of MOS capacitors and IGFETs is described.
Inventors
- 👤 Won-Tien Tsang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 01:50
CPC Classifications
H; H10; H10P; H10P14/00; H10P14/60; H10P14/69; H10P14/692; H10P14/6938; H10P14/6939; H10P14/69391; H10D; H10D64/00; H10D64/01; H10D64/013; H10D64/01358; H10P14/63; H10P14/6302; H10P14/6304; H10P14/6306; H10P14/6312; H10P14/6322
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
98 words
An MIS capacitor comprising: a GaAs single crystal semiconductor body, an insulating layer formed on a major surface of said body, and a metal electrode formed on said insulating layer, characterized in that: said insulating layer is formed by a process comprising the steps of: epitaxially growing a layer of Al x Ga 1-x As on said body and thermally treating said Al x Ga 1-x As in an atmosphere containing oxygen for a time sufficient to convert said Al x Ga 1-x As layer to said insulating layer, said conversion being essentially self-terminating at said major surface.
Claim 2
Dependent Claim
98 words
An MIS capacitor comprising: a GaAs single crystal semiconductor body, an insulating layer formed on a major surface of said body, and a metal electrode formed on said insulating layer, characterized in that: said insulating layer is formed by a process comprising the steps of: epitaxially growing a layer of Al x Ga 1-x As on said body and thermally treating said Al x Ga 1-x As in an atmosphere containing oxygen for a time sufficient to convert said Al x Ga 1-x As layer to said insulating layer, said conversion being essentially self-terminating at said major surface.
Claim 3
Dependent Claim
30 words
The capacitor of claim 1 wherein said insulating layer has a thickness d ox and said Al x Ga 1-x As layer has a thickness d ox /1.8 when x=1.0.
Claim 4
Dependent Claim
33 words
The capacitor of claim 1 wherein the Al composition of said Al x Ga 1-x As layer is graded so that x is smaller near said major surface than it is farther therefrom.
Claim 5
Dependent Claim
12 words
The capacitor of claim 1 wherein x is substantially equal to 1.0.
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) | 1984-09-21 | 1985-03-23 | 1985-09-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-09-21 | 1989-03-23 | 1989-09-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-09-21 | 1993-03-23 | 1993-09-22 | $7700.00 | Window Closed / Lapsed |