US5930611A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for fabricating MIS device having GATE insulator of GaS or gallium sulfide
Assignee: Fujitsu Ltd
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Filing: 1997-09-04
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Granted: 1999-07-27
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Expires: 2017-09-04
Abstract
Abstract A semiconductor device is fabricated by the step of forming a gate insulation film of a GaS film on a compound semiconductor layer; the step of forming an inter-layer insulation film on the gate insulation film; the step of etching the inter-layer insulation film selectively with respect to the gate insulation film by the use of an etchant containing hydrogen fluoride and ammonium fluoride, the step of exposing a prescribed region of the gate insulation film; and the step of forming a gate electrode on the exposed gate insulation film.
Inventors
- 👤 Naoya Okamoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 14:10
CPC Classifications
H; H10; H10D; H10D64/00; H10D64/60; H10D64/66; H10D64/68; H10D64/691; H10D30/00; H10D30/01; H10D30/021; H10D30/60; H10D64/01; H10D64/013; H10D64/01302; H10D64/01332; H10P; H10P50/00; H10P50/20; H10P50/28; H10P50/282; H10P50/283; H10D62/00; H10D62/80; H10D62/85
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
43 words
A method for fabricating a semiconductor device comprising etching a SiO 2 film, a SiON film or a SiN film formed on a GaS film selectively with respect to the GaS film by use of an etchant containing hydrogen fluoride and ammonium fluoride.
Claim 2
Independent Claim
43 words
A method for fabricating a semiconductor device comprising etching a SiO 2 film, a SiON film or a SiN film formed on a GaS film selectively with respect to the GaS film by use of an etchant containing hydrogen fluoride and ammonium fluoride.
Claim 3
Dependent Claim
35 words
A method for fabricating a semiconductor device according to claim 1, wherein the etchant contains ammonium fluoride by an above 8 mixing ratio in terms of mass versus a 1 mixing ratio of hydrogen fluoride.
Claim 4
Independent Claim
79 words
A method for fabricating a semiconductor device comprising the steps of: forming a gate insulation film of a GaS film on a compound semiconductor layer; forming an inter-layer insulation film of a SiO 2 film, SiON film or SiN film on the gate insulation film; etching the inter-layer insulation film selectively with respect to the gate insulation film to expose a prescribed region of the gate insulation film; and forming a gate electrode on the exposed gate insulation film.
Claim 5
Independent Claim
79 words
A method for fabricating a semiconductor device comprising the steps of: forming a gate insulation film of a GaS film on a compound semiconductor layer; forming an inter-layer insulation film of a SiO 2 film, SiON film or SiN film on the gate insulation film; etching the inter-layer insulation film selectively with respect to the gate insulation film to expose a prescribed region of the gate insulation film; and forming a gate electrode on the exposed gate insulation film.
Claim 6
Dependent Claim
27 words
A method for fabricating a semiconductor device according to claim 3, wherein the inter-layer insulation film is etched by an etchant containing hydrogen fluoride and ammonium fluoride.
Claim 7
Dependent Claim
35 words
A method for fabricating a semiconductor device according to claim 4, wherein the etchant contains ammonium fluoride by an above 8 mixing ratio in terms of mass versus a 1 mixing ratio of hydrogen fluoride.
References Cited (Backward Citations)
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