US4211601A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device fabrication by plasma etching
Assignee: AT&T Inc
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Filing: 1978-07-31
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Granted: 1980-07-08
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Expires: 1998-07-31
Abstract
Abstract Integrated circuit fabrication, e.g., silicon LSI is expedited by plasma etching in any of a novel class of etchants. Appropriate plasma environments are produced by introduction of fluorocarbon-halogenation combinations as exemplified by CF3Cl.
Inventors
- 👤 Cyril J. Mogab
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 17:04
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/20; H10P50/24; H10P50/242; C; C23; C23F; C23F4/00
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
138 words
Process for fabrication of an article comprising at least one operation during which the article undergoing fabrication comprises a surface of material to be etched, wherein the said article is etched within a plasma environment contained within an apparatus, the plasma resulting from imposition of an electrical field across gaseous reactant between two electrodes, the material to be etched comprising a silicon-containing composition, etching being primarily due to chemical reaction with the said material to be etched, CHARACTERIZED IN THAT the said gaseous reactant comprises the equivalent of a mixture of at least one halide and a halogen which in the said plasma results in the said chemical reaction in which the said halide is a fluorocarbon and in which the said gaseous reactant has an equivalent fluorocarbon/atomic halogen ratio greater than that contained in CF 3 Cl.
Claim 2
Dependent Claim
138 words
Process for fabrication of an article comprising at least one operation during which the article undergoing fabrication comprises a surface of material to be etched, wherein the said article is etched within a plasma environment contained within an apparatus, the plasma resulting from imposition of an electrical field across gaseous reactant between two electrodes, the material to be etched comprising a silicon-containing composition, etching being primarily due to chemical reaction with the said material to be etched, CHARACTERIZED IN THAT the said gaseous reactant comprises the equivalent of a mixture of at least one halide and a halogen which in the said plasma results in the said chemical reaction in which the said halide is a fluorocarbon and in which the said gaseous reactant has an equivalent fluorocarbon/atomic halogen ratio greater than that contained in CF 3 Cl.
Claim 3
Dependent Claim
22 words
Process of claim 1 in which the said halogen is selected from the group consisting of Cl 2 and Br 2 .
Claim 4
Dependent Claim
19 words
Process of claim 1 in which the said fluorocarbon is selected from the group consisting of chlorofluorocarbon and bromofluorocarbon.
Claim 5
Dependent Claim
16 words
Process of claim 3 in which the said gaseous reactant consists essentially of the said fluorocarbon.
Claim 6
Dependent Claim
14 words
Process of claim 4 in which the said gaseous reactant contains CF 3 Cl.
Claim 7
Dependent Claim
14 words
Process of claim 4 in which the said gaseous reactant contains CF 3 Br.
Claim 8
Dependent Claim
12 words
Process of claim 6 in which the said gaseous reactant includes helium.
Claim 9
Dependent Claim
33 words
Process of claim 1 in which the said gaseous reactant contains two chemically distinct species at least the first of which is a halide, at least the second of which is a halogen.
Claim 10
Dependent Claim
17 words
Process of claim 1 in which the said fluorocarbon consists essentially of C 2 F 6 .
Claim 11
Dependent Claim
15 words
Process of claim 9 in which the said halogen consists essentially of Cl 2 .
Claim 12
Dependent Claim
29 words
Process of any of claims, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 in which the said material to be etched consists primarily of elemental silicon.
Claim 13
Dependent Claim
14 words
Process of claim 11 in which the said material contains at least one silicide.
Claim 14
Dependent Claim
15 words
Process of claim 11 in which the said material to be etched comprises polycrystalline silicon.
Claim 15
Dependent Claim
16 words
Process of claim 13 in which the said polycrystalline silicon is doped with an extrinsic impurity.
Claim 16
Dependent Claim
13 words
Process of claim 11 in which the said elemental silicon is single crystal.
Claim 17
Dependent Claim
16 words
Process of claim 1 in which etching is limited to selected regions of the said surface.
Claim 18
Dependent Claim
21 words
Process of claim 16 in which the said selected regions correspond with regions bared through apertures of an overlying masking layer.
Claim 19
Dependent Claim
18 words
Process of claim 17 in which the said masking layer consists essentially of an organic resist masking layer.
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) | 1983-07-08 | 1984-01-07 | 1984-07-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-07-08 | 1988-01-07 | 1988-07-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-07-08 | 1992-01-07 | 1992-07-08 | $7700.00 | Window Closed / Lapsed |