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US4904338A
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Carbon enhanced vapor etching
Assignee: Arizona's Public Universities
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Filing: 1988-09-23
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Granted: 1990-02-27
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Expires: 2008-09-23
Abstract
Abstract A carbon enhanced vapor etching process which eliminates resist development, avoids contact with wet chemicals and plasma, and employs simple universally available process equipment. The process is based on the discovery that the etch rate of silicon dioxide in hydrogen fluoride is greatly enhanced in the presence of carbon. Carbon is provided by an organic or inorganic material deposited on or in the surface of the silicon.
Inventors
- 👤 Michael N. Kozicki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 06:11
CPC Classifications
C; C03; C03C; C03C15/00; H; H10; H10P; H10P50/00; H10P50/20; H10P50/28; H10P50/282; H10P50/283
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
25 words
A method of effecting pattern definitions on or in silicon dioxide comprising etching said silicon dioxide in hydrogen fluoride in the selective presence of carbon.
Claim 2
Independent Claim
25 words
A method of effecting pattern definitions on or in silicon dioxide comprising etching said silicon dioxide in hydrogen fluoride in the selective presence of carbon.
Claim 3
Dependent Claim
21 words
A method according to claim 1 in which said carbon is selectively applied to silicon dioxide as an inorganic carbon compound.
Claim 4
Dependent Claim
22 words
A method according to claim 1 in which said carbon is selectively applied to said silicon dioxide as an organic carbon compound.
Claim 5
Dependent Claim
13 words
A method according to claim 1 in which said carbon source is photoresist.
Claim 6
Dependent Claim
16 words
A method according to claim 2 in which said carbon is deposited on said silicon dioxide.
Claim 7
Dependent Claim
16 words
A method according to claim 3 in which said carbon is deposited on said silicon dioxide.
Claim 8
Dependent Claim
16 words
A method according to claim 4 in which said carbon is deposited on said silicon dioxide.
Claim 9
Dependent Claim
16 words
A method according to claim 2 in which said carbon is deposited in said silicon dioxide.
Claim 10
Dependent Claim
16 words
A method according to claim 3 in which said carbon is deposited in said silicon dioxide.
Claim 11
Dependent Claim
16 words
A method according to claim 4 in which said carbon is deposited in said silicon dioxide.
Claim 12
Dependent Claim
47 words
A method according to claim 1 in which said carbon is deposited on or in said silicon dioxide by a spin-on technique, physical vapor deposition, chemical vapor deposition, ion-implantation, focused ion-beam implantation, Langmuir-Blodgett film formation or by laser beam, electron beam or ion-beam stimulated chemical vapor deposition.
Claim 13
Dependent Claim
32 words
A method according to claim 4 in which said resist is exposed by a method selected from the group consisting of deep ultra-violet, highly focused electron-beam, ion-beam, laser-beam, blanket ion-beam and x-ray.
Claim 14
Dependent Claim
18 words
A method according to claim 1 in which said hydrogen fluoride is hydrated vapor in a nitrogen carrier.
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) | 1993-02-26 | 1993-08-28 | 1994-02-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-02-26 | 1997-08-28 | 1998-02-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-02-26 | 2001-08-28 | 2002-02-27 | $7700.00 | Window Closed / Lapsed |