Patent US4511430A successfully refreshed from Google Patents.
US4511430A
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Control of etch rate ratio of SiO2 /photoresist for quartz planarization etch back process
Assignee: International Business Machines Corp
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Filing: 1984-01-30
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Granted: 1985-04-16
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Expires: 2004-01-30
Abstract
Abstract A method of controlling the etch rate ratio of SiO2/photoresist (PR) in a quartz planarization etch back process involves etching with a gaseous mixture containing CF4 and either CHF3 or CxFy with x>1 or O2. The preferred SiO2/PR ratio of 1.2+/-0.1 is obtained by either adding CHF3 to decrease the etch rate of the PR or by adding O2 to increase the etch rate of the PR.
Inventors
- 👤 Lee Chen
- 👤 Gangadhara S. Mathad
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 04:44
CPC Classifications
H; H10; H10P; H10P95/00; H10P95/06; H10P95/062; H10P95/064; H10P50/00; H10P50/20; H10P50/28; H10P50/282; H10P50/283; H10P50/286; H10P50/287
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
72 words
A method for uniformly etching a surface which includes both silicon dioxide and an organic polymer material comprising the steps of contacting said surface with a reactive etching plasma which contains CF 4 and a gas taken from the group consisting of CHF 3 and C x F y with x>1 to cause the structure formed by said etching step to be substantially planar and have an etch rate ratio of 1.2±0.1.
Claim 2
Independent Claim
72 words
A method for uniformly etching a surface which includes both silicon dioxide and an organic polymer material comprising the steps of contacting said surface with a reactive etching plasma which contains CF 4 and a gas taken from the group consisting of CHF 3 and C x F y with x>1 to cause the structure formed by said etching step to be substantially planar and have an etch rate ratio of 1.2±0.1.
Claim 3
Dependent Claim
15 words
A method as described in claim 1 whereby said etching plasma contains CHF 3 .
Claim 4
Dependent Claim
18 words
A method as described in claim 2 whereby the gaseous mixture contains 0.5 to 5.0% CHF 3 .
Claim 5
Dependent Claim
25 words
A method as described in claim 1 including the step of evacuating said structure to a pressure of not less than 500 microns of mercury.
Claim 6
Dependent Claim
14 words
A method as described in claim 1 whereby said reactive etching plasma contains oxygen.
Claim 7
Dependent Claim
21 words
A method as described in claim 5 whereby the reactive etching plasma contains 0.5 to 10 volume % O 2 .
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) | 1988-04-15 | 1988-10-15 | 1989-04-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-04-15 | 1992-10-15 | 1993-04-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-04-15 | 1996-10-15 | 1997-04-16 | $7700.00 | Window Closed / Lapsed |