Patent US4465553A successfully refreshed from Google Patents.
US4465553A
Expired / Lapsed
US
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Method for dry etching of a substrate surface
Assignee: TOKYO DENSHI KAGAKU Co Ltd 251 NAKAMARUKO NAKAHARA-KU KAWASAKI-SHI KANAGAWA-KEN JAPAN A CORP OF
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Filing: 1983-11-15
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Granted: 1984-08-14
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Expires: 2003-11-15
Abstract
Abstract The invention provides a method for fine pattern-wise etching of a surface layer on a substrate such as semiconductor silicon wafers in a dry process by use of a gaseous mixture of pentafluorochloroethane and sulfur hexafluoride as the etching gas to support the plasma atmosphere. The inventive method is advantageous in the compatibility of the requirements for a large etching rate and a high precision of the fine patterning in contrast to the generally accepted understanding that these two requirements are not compatible with each other since an etching gas having a high etching rate causes remarkable side etching to decrease the precision of the desired patterning.
Inventors
- 👤 Isamu Hijikata
- 👤 Akira Uehara
- 👤 Hisashi Nakane
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 23:32
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/20; H10P50/24; H10P50/242; H10P50/26; H10P50/264; H10P50/266; H10P50/267; H10P50/268; H10P50/28; H10P50/282; H10P50/283
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
40 words
A method for pattern-wise etching of a surface layer of a substrate by a dry process which comprises exposing the surface layer on the substrate to an atmosphere of plasma generated in a gaseous mixture of pentafluorochloroethane and sulfur hexafluoride.
Claim 2
Independent Claim
40 words
A method for pattern-wise etching of a surface layer of a substrate by a dry process which comprises exposing the surface layer on the substrate to an atmosphere of plasma generated in a gaseous mixture of pentafluorochloroethane and sulfur hexafluoride.
Claim 3
Dependent Claim
30 words
The method as claimed in claim 1 wherein the ratio of the pentafluorochloroethane and sulfur hexafluoride in the gaseous mixture is in the range from 5:95 to 95:5 by volume.
References Cited (Backward Citations)
US4330384A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-08-14 | 1988-02-13 | 1988-08-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-08-14 | 1992-02-13 | 1992-08-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-08-14 | 1996-02-13 | 1996-08-14 | $7700.00 | Window Closed / Lapsed |