US4372807A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Plasma etching of aluminum
Assignee: Intersil Corp
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Filing: 1982-03-25
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Granted: 1983-02-08
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Expires: 2002-03-25
Abstract
Abstract A method of improving the uniformity and line-width control in the plasma etching of aluminum and its alloys by adding to the etchant gas an effective amount of a gaseous hydrocarbon which will polymerize under glow discharge conditions.
Inventors
- 👤 John L. Vossen, Jr.
- 👤 Bernard Halon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 21:17
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/20; H10P50/26; H10P50/264; H10P50/266; H10P50/267; C; C23; C23F; C23F4/00
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
51 words
In a process of plasma etching aluminum or an alloy thereof with an etchant gas which will isotropically etch the sidewalls of patterns being etched, the improvement comprising adding to the etchant gas gaseous hydrocarbon which will polymerize under conditions of glow discharge in an amount effective to reduce sidewall etching.
Claim 2
Dependent Claim
51 words
In a process of plasma etching aluminum or an alloy thereof with an etchant gas which will isotropically etch the sidewalls of patterns being etched, the improvement comprising adding to the etchant gas gaseous hydrocarbon which will polymerize under conditions of glow discharge in an amount effective to reduce sidewall etching.
Claim 3
Dependent Claim
14 words
A process in accordance with claim 1, wherein said etchant gas contains boron trichloride.
Claim 4
Dependent Claim
19 words
A process in accordance with claim 2, wherein said etchant gas is a mixture of boron trichloride and chlorine.
Claim 5
Dependent Claim
20 words
A process in accordance with claim 2, wherein said etchant gas is a mixture of boron trichloride, chlorine and helium.
Claim 6
Dependent Claim
23 words
A process in accordance with claim 1, wherein the gaseous hydrocarbon is selected from the group consisting of ethylene, cyclopropane and mixtures thereof.
Claim 7
Dependent Claim
13 words
The process in accordance with claim 5, wherein the gaseous hydrocarbon is cyclopropane.
Claim 8
Dependent Claim
49 words
The process in accordance with claim 1, wherein the amount of gaseous hydrocarbon added to the etchant gas mixture is from about 7×10 -6 to about 2.5×10 -5 percent by volume when the total flow of etching gas is about 50 sccm and the pressure is about 125 mtorr.
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) | 1986-02-07 | 1986-08-09 | 1987-02-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-02-07 | 1990-08-09 | 1991-02-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-02-07 | 1994-08-09 | 1995-02-08 | $7700.00 | Window Closed / Lapsed |