US4226667A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Oxide masking of gallium arsenide
Assignee: AT&T Inc
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Filing: 1978-10-31
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Granted: 1980-10-07
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Expires: 1998-10-31
Abstract
Abstract The use of gallium arsenide as an electronic material is increasing in popularity. However, its utility for planar MOS technology is hindered by the fact that its native oxide stabilizes upon heating and becomes etch resistant. I have discovered that it is the vaporization of arsenic containing compounds in the oxide which renders the oxide insoluble. A technique is described wherein an inert capping layer is disposed on a layer of the native oxide prior to heat exposure. This prevents evaporation of arsenic, and both the capping layer and the oxide are capable of subsequent dissolution in a weak acid or base.
Inventors
- 👤 Ralph A. Logan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 09:53
CPC Classifications
H; H10; H10P; H10P14/00; H10P14/60; H10P14/63; H10P14/6302; H10P14/6304; H10P14/6306; H10P14/6312; H10P14/6324; H10P95/00; H10P95/90; H10P95/904; Y; Y10; Y10S; Y10S438/00; Y10S438/902; Y10S438/942
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
88 words
In a process of manufacturing an Al x Ga 1-x As device which includes the formation of a layer of native oxide on the device that is to be selectively patterned subsequent to the heating of the device to a temperature at which the oxide becomes insoluble as a result of change in composition of the oxide and more resistant to selective patterning, the step of covering the native oxide with a capping material which prevents the change in composition during subsequent heating whereby selective patterning is facilitated.
Claim 2
Dependent Claim
88 words
In a process of manufacturing an Al x Ga 1-x As device which includes the formation of a layer of native oxide on the device that is to be selectively patterned subsequent to the heating of the device to a temperature at which the oxide becomes insoluble as a result of change in composition of the oxide and more resistant to selective patterning, the step of covering the native oxide with a capping material which prevents the change in composition during subsequent heating whereby selective patterning is facilitated.
Claim 3
Dependent Claim
95 words
In a process of manufacturing a semiconductor device, a method comprising: (a) firstly forming a native oxide layer on an Al x Ga 1-x As (0≦x≦1) body; (b) secondly depositing a capping layer on said native oxide to prevent evaporation of arsenic in said native oxide during subsequent heating steps; (c) thirdly heating said body to a temperature at which the evaporation of arsenic from said native oxide would take place in the absence of said capping layer; and (d) finally etching to remove at least a portion of said capping layer and said oxide.
Claim 4
Dependent Claim
95 words
In a process of manufacturing a semiconductor device, a method comprising: (a) firstly forming a native oxide layer on an Al x Ga 1-x As (0≦x≦1) body; (b) secondly depositing a capping layer on said native oxide to prevent evaporation of arsenic in said native oxide during subsequent heating steps; (c) thirdly heating said body to a temperature at which the evaporation of arsenic from said native oxide would take place in the absence of said capping layer; and (d) finally etching to remove at least a portion of said capping layer and said oxide.
Claim 5
Dependent Claim
24 words
The process of claim 1 wherein step (b) comprises depositing a dielectric material selected from the group consisting of silicon dioxide and silicon nitride.
Claim 6
Dependent Claim
16 words
The process of claim 1 wherein step (b) comprises depositing a layer of an inert metal.
Claim 7
Dependent Claim
11 words
The process of claim 4 wherein said inert metal is gold.
Claim 8
Dependent Claim
10 words
The process of claim 1 wherein step (a)comprises anodic oxidation.
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) | 1983-10-07 | 1984-04-07 | 1984-10-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-10-07 | 1988-04-07 | 1988-10-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-10-07 | 1992-04-07 | 1992-10-07 | $7700.00 | Window Closed / Lapsed |