Patent US4040893A successfully refreshed from Google Patents.
US4040893A
Expired / Lapsed
US
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Method of selective etching of materials utilizing masks of binary silicate glasses
Assignee: General Electric Co
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Filing: 1976-04-12
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Granted: 1977-08-09
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Expires: 1996-04-12
Abstract
Abstract A method of etching a layer of material on the surface of a substrate of silicon dioxide utilizes an etch mask constituted of a binary silicate glass. The binary silicate glass is removed subsequent to the etching of the layer without affecting the substrate of silicon dioxide.
Inventors
- 👤 Mario Ghezzo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 12:50
CPC Classifications
H; H10; H10F; H10F71/00; H10F71/138; H10P; H10P50/00; H10P50/20; H10P50/28; H10P50/282; H10P50/283; H10P50/60; H10P50/66; H10P50/663; H10P50/667; Y; Y02; Y02E; Y02E10/00; Y02E10/50
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
106 words
A method of etching a first pattern in a layer of material formed on the surface of a substrate including a region of silicon dioxide comprising depositing a film of a binary silicate glass on the exposed surface of said layer, forming in said film a second pattern which is substantially identical to said first pattern to expose portions of said layer of material uncovered thereby, etching said uncovered portions of said layer with a first etchant which does not etch silicon dioxide, removing said film of binary silicate glass with a second etchant which does not etch silicon dioxide or the material of said layer.
Claim 2
Independent Claim
106 words
A method of etching a first pattern in a layer of material formed on the surface of a substrate including a region of silicon dioxide comprising depositing a film of a binary silicate glass on the exposed surface of said layer, forming in said film a second pattern which is substantially identical to said first pattern to expose portions of said layer of material uncovered thereby, etching said uncovered portions of said layer with a first etchant which does not etch silicon dioxide, removing said film of binary silicate glass with a second etchant which does not etch silicon dioxide or the material of said layer.
Claim 3
Dependent Claim
19 words
The method of claim 1 in which said layer of material is formed on said region of silicon dioxide.
Claim 4
Dependent Claim
23 words
The method of claim 1 in which said film of binary silicate glass is selected from the class of borosilicate and phosphosilicate glasses.
Claim 5
Dependent Claim
22 words
The method of claim 3 in which said film is a borosilicate glass and in which said second etchant is tetrafluoroboric acid.
Claim 6
Dependent Claim
21 words
The method of claim 3 in which said film is a phosphosilicate glass and in which said second etchant is P-etch.
Claim 7
Dependent Claim
22 words
The method of claim 3 in which said layer of material is indium tin oxide having a major constituent of indium oxide.
Claim 8
Dependent Claim
14 words
The method of claim 6 in which said first etchant is concentrated hydrobromic acid.
Claim 9
Dependent Claim
22 words
The method of claim 3 in which said layer of material is antimony tin oxide having a major constituent of tin oxide.
Claim 10
Dependent Claim
15 words
The method of claim 8 in which said first etchant is hot concentrated hydroiodic acid.
Claim 11
Dependent Claim
14 words
The method of claim 3 in which said layer of material is polycrystalline silicon.
Claim 12
Dependent Claim
15 words
The method of claim 10 in which said first etchant is concentrated hot potassium hydroxide.
Claim 13
Dependent Claim
14 words
The method of claim 3 in which said layer of material is silicon nitride.
Claim 14
Dependent Claim
15 words
The method of claim 12 in which said first etchant is concentrated hot phosphoric acid.
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) | 1980-08-08 | 1981-02-07 | 1981-08-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-08-08 | 1985-02-07 | 1985-08-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-08-08 | 1989-02-07 | 1989-08-09 | $7700.00 | Window Closed / Lapsed |