US4687543A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Selective plasma etching during formation of integrated circuitry
Assignee: Motorola Solutions Inc
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Filing: 1986-02-21
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Granted: 1987-08-18
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Expires: 2006-02-21
Abstract
Abstract A method is disclosed for removing (etching) an insulating layer form an electrically semiconductive material wherein a volatile fluoride is substituted for a hydrocarbon in gases for selective plasma discharges. The removing is done without polymer build-up and loss of selectivity.
Inventors
- 👤 Christopher D. Bowker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 17:10
CPC Classifications
C; C03; C03C; C03C15/00; H; H10; H10P; H10P50/00; H10P50/20; H10P50/28; H10P50/282; H10P50/283
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
57 words
A method for selectively etching an insulating layer overlying a body of material including silicon comprising the steps of: subjecting said layer to a plasma discharge in a gas mixture containing sulfur hexafluoride and a fluorocarbon wherein the flow rate of said sulphur hexafluoride is approximately equal to or greater than the flow rate of said fluorocarbon.
Claim 2
Independent Claim
57 words
A method for selectively etching an insulating layer overlying a body of material including silicon comprising the steps of: subjecting said layer to a plasma discharge in a gas mixture containing sulfur hexafluoride and a fluorocarbon wherein the flow rate of said sulphur hexafluoride is approximately equal to or greater than the flow rate of said fluorocarbon.
Claim 3
Dependent Claim
10 words
The method of claim 1 wherein said fluorocarbon is fluoroform.
Claim 4
Dependent Claim
24 words
The method of claim 1 wherein the material of said insulating layer is selected from the group consisting of silicon nitride and silicon dioxide.
Claim 5
Dependent Claim
15 words
The method of claim 1 wherein the material of said insulating layer is silicon dioxide.
Claim 6
Dependent Claim
13 words
The method of claim 1 wherein said material of said body is silicon.
Claim 7
Dependent Claim
32 words
The method as set forth in claim 1 and further comprising as an additional step: subjecting said material to a plasma discharge in a gas mixture containing sulphur hexafluoride and a fluorocarbon.
Claim 8
Dependent Claim
28 words
The method as set forth in claim 6 wherein said additional step comprises: subjecting said material to a plasma in a gas mixture wherein the fluorocarbon comprises fluoroform.
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) | 1990-08-17 | 1991-02-16 | 1991-08-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-08-17 | 1995-02-16 | 1995-08-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-08-17 | 1999-02-16 | 1999-08-18 | $7700.00 | Window Closed / Lapsed |