Patent US4375385A successfully refreshed from Google Patents.
US4375385A
Expired / Lapsed
US
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Plasma etching of aluminum
Assignee: Intersil Corp
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Filing: 1982-03-25
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Granted: 1983-03-01
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Expires: 2002-03-25
Abstract
Abstract A method of improving uniformity of etching in the plasma etching of a substrate of aluminum and its alloys by supporting the substrate on a getter plate of a metal such as tantalum. The getter plate extends beyond the substrate for a distance sufficient to improve the uniformity of etching across the substrate.
Inventors
- 👤 Bernard Halon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 14:37
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: 10
Claim 1
Independent Claim
56 words
In a process of plasma etching a substrate of aluminum or an alloy thereof with an etchant gas containing boron trichloride, the improvement comprising supporting the substrate on a metal getter plate which extends outwardly from the edges of the substrate for a distance sufficient to cause substantially uniform etching across the substrate having improved uniformity.
Claim 2
Dependent Claim
56 words
In a process of plasma etching a substrate of aluminum or an alloy thereof with an etchant gas containing boron trichloride, the improvement comprising supporting the substrate on a metal getter plate which extends outwardly from the edges of the substrate for a distance sufficient to cause substantially uniform etching across the substrate having improved uniformity.
Claim 3
Dependent Claim
19 words
A process in accordance with claim 1, wherein the substrate and the getter plate have substantially the same shape.
Claim 4
Dependent Claim
39 words
A process in accordance with claim 2, wherein the substrate and the getter plate are in the shape of a disc and the diameter of the getter plate is at least about one-sixth greater than that of the substrate.
Claim 5
Dependent Claim
23 words
A process in accordance with claim 3, wherein the diameter of the getter plate is about one-third greater than that of the substrate.
Claim 6
Dependent Claim
28 words
A process in accordance with claim 1, wherein the metal of the plate is selected from the group consisting of tantalum, stainless steel, molybdenum, nickel, tungsten and gold.
Claim 7
Dependent Claim
12 words
A process in accordance with claim 5, wherein the metal is tantalum.
Claim 8
Dependent Claim
30 words
A process in accordance with claim 1, wherein said etchant gas contains a gaseous hydrocarbon which will polymerize under conditions of glow discharge in an amount effective to reduce undercutting.
Claim 9
Dependent Claim
23 words
A process in accordance with claim 7, wherein said gaseous hydrocarbon is selected from the group consisting of ethylene, cyclopropane and mixtures thereof.
Claim 10
Dependent Claim
13 words
A process in accordance with claim 8, wherein said gaseous hydrocarbon is cyclopropane.
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) | 1986-02-28 | 1986-08-30 | 1987-03-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-02-28 | 1990-08-30 | 1991-03-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-02-28 | 1994-08-30 | 1995-03-01 | $7700.00 | Window Closed / Lapsed |