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US4227975A Expired / Lapsed US ⏱️ 0.0 years remaining

Selective plasma etching of dielectric masks in the presence of native oxides of group III-V compound semiconductors

Assignee: AT&T Inc
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Filing: 1979-01-29
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Granted: 1980-10-14
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Expires: 1999-01-29
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Abstract

Abstract Plasma etching is described as a selective etch for dielectric masks such as SiO 2 , Si 3 N 4 and certain photoresists in the presence of native oxides of Group III-V compound semiconductors. This process can be used in the fabrication of mesa junction lasers and Burrus light emitting diodes.

Inventors

  • 👤 Robert L. Hartman
  • 👤 Louis A. Koszi
  • 👤 Cyril J. Mogab
  • 👤 Bertram Schwartz

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 22:18
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/20; H10P50/28; H10P50/286; H10P50/287; H10P50/282; H10P50/283

Claims Analysis

Total Claims: 16
Claim 1
Independent Claim 59 words
A method of selectively removing a layer of dielectric material from a surface of a Group III-V compound semiconductor without also removing a layer of native oxide on said surface by subjecting both of said layers simultaneously to plasma etching in an atmosphere effective to remove said dielectric layer without attacking said native oxide or said Group III-V semi-conductor.
Claim 2
Independent Claim 59 words
A method of selectively removing a layer of dielectric material from a surface of a Group III-V compound semiconductor without also removing a layer of native oxide on said surface by subjecting both of said layers simultaneously to plasma etching in an atmosphere effective to remove said dielectric layer without attacking said native oxide or said Group III-V semi-conductor.
Claim 3
Dependent Claim 44 words
The method of claim 1 wherein the Group III element of said compound is selected from the Group consisting of Ga, Al, In and combinations thereof and said Group V element is selected from the Group consisting of As, P, Sb and combinations thereof.
Claim 4
Dependent Claim 25 words
The method of claim 2 wherein said dielectric material is selected from the group consisting of SiO 2 , Si 3 N 4 and photoresist.
Claim 5
Independent Claim 19 words
The method of claims 2 or 3 wherein said plasma etching takes place in an atmosphere including a halocarbon.
Claim 6
Dependent Claim 43 words
The method of claim 4 wherein said plasma etching takes place in an atmosphere selected from the group consisting of CF 4 and oxygen, C 2 F 6 , CHF 3 , and mixtures of C 2 F 6 and CHF 3 .
Claim 7
Independent Claim 108 words
A method of forming a patterned native oxide layer on a surface of a Group III-V compound semiconductor body comprising the steps of: (a) forming on said surface a dielectric layer which can be selectively plasma etched relative to said body and to a native oxide layer to be subsequently formed thereon; (b) patterning said dielectric layer to form windows which expose underlying portions of said surface; (c) forming a native oxide layer on said exposed portions; and (d) subjecting said body and both of said layers simultaneously to plasma etching in an atmosphere effective to remove said dielectric layer without attacking said native oxide or said body.
Claim 8
Independent Claim 108 words
A method of forming a patterned native oxide layer on a surface of a Group III-V compound semiconductor body comprising the steps of: (a) forming on said surface a dielectric layer which can be selectively plasma etched relative to said body and to a native oxide layer to be subsequently formed thereon; (b) patterning said dielectric layer to form windows which expose underlying portions of said surface; (c) forming a native oxide layer on said exposed portions; and (d) subjecting said body and both of said layers simultaneously to plasma etching in an atmosphere effective to remove said dielectric layer without attacking said native oxide or said body.
Claim 9
Dependent Claim 25 words
The method of claim 6 wherein said dielectric layer is selected from the group consisting of SiO 2 , Si 3 N 4 and photoresist.
Claim 10
Independent Claim 23 words
The method of claims 6 or 7 wherein said forming step (c) comprises anodically growing said native oxide layer on said exposed portions.
Claim 11
Independent Claim 13 words
The method of claims 6 or 7 wherein said atmosphere includes a halocarbon.
Claim 12
Dependent Claim 38 words
The method of claim 9 wherein said atmosphere is selected from the group consisting of CF 4 and oxygen, C 2 F 6 , CHF 3 , and mixtures of C 2 F 6 and CHF 3 .
Claim 13
Independent Claim 49 words
The method of claims 6 or 7 including between steps (b) and (c) the additional step of forming grooves in said windows in said exposed underlying portions, thereby forming mesas in said body between said grooves, and wherein step (c) includes forming said native oxide layer in said grooves.
Claim 14
Dependent Claim 32 words
The method of claim 11 including after step (d) the additional step of depositing a metal layer on the tops of said mesas and on said native oxide layers in said grooves.
Claim 15
Dependent Claim 30 words
The method of claim 11 including after step (d) the additional step of selectively forming metal layers on the tops of said mesas but not on said native oxide layers.
Claim 16
Dependent Claim 15 words
The method of claim 13 wherein said selective forming step comprises electroplating said metal layer.

References Cited (Backward Citations)

US3795557A Cited
US3867216A Cited
US3880684A Cited
US4011113A Cited
US3975252A Cited
US4030967A Cited
US4110661A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1983-10-14 1984-04-14 1984-10-14 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1987-10-14 1988-04-14 1988-10-14 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1991-10-14 1992-04-14 1992-10-14 $7700.00 Window Closed / Lapsed

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