Patent US4169807A successfully refreshed from Google Patents.
US4169807A
Expired / Lapsed
US
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Novel solvent drying agent
Assignee: RCA Corp
•
Filing: 1978-03-20
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Granted: 1979-10-02
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Expires: 1998-03-20
Abstract
Abstract Mixtures of 1-propanol, water and certain perfluoro compounds form excellent drying agents for silicon based devices. The mixtures have good wetting properties and form azeotropic mixtures in the vapor phase.
Inventors
- 👤 John R. Zuber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 01:20
CPC Classifications
H; H10; H10P; H10P70/00; H10P70/10; H10P70/15; C; C11; C11D; C11D7/00; C11D7/50; C11D7/5036; C11D7/504; C11D7/5063; C23; C23G; C23G5/00; C23G5/02
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
19 words
An azeotropic mixture of 1-propanol, water and a perfluoro compound selected from the group consisting of perfluoro-2-butyltetrahydrofuran and perfluoro-1,4-dimethylcyclohexane.
Claim 2
Dependent Claim
19 words
An azeotropic mixture of 1-propanol, water and a perfluoro compound selected from the group consisting of perfluoro-2-butyltetrahydrofuran and perfluoro-1,4-dimethylcyclohexane.
Claim 3
Dependent Claim
11 words
A mixture according to claim 1 wherein the compound is perfluoro-2-butyltetrahydrofuran.
Claim 4
Dependent Claim
11 words
A mixture according to claim 1 wherein the compound is perfluoro-1,4-dimethylcyclohexane.
Claim 5
Independent Claim
37 words
A method of drying silicon wafers which comprises rinsing said devices with water, immersing in a hot azeotropic mixture of 1-propanol, water and a perfluoro compound selected from the group consisting of perfluoro-2-butyltetrahydrofuran and perfluoro-1,4-dimethylcyclohexane and draining.
Claim 6
Independent Claim
37 words
A method of drying silicon wafers which comprises rinsing said devices with water, immersing in a hot azeotropic mixture of 1-propanol, water and a perfluoro compound selected from the group consisting of perfluoro-2-butyltetrahydrofuran and perfluoro-1,4-dimethylcyclohexane and draining.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-10-01 | 1983-04-02 | 1983-10-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-10-01 | 1987-04-02 | 1987-10-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-10-01 | 1991-04-02 | 1991-10-02 | $7700.00 | Window Closed / Lapsed |