Patent US4345804A successfully refreshed from Google Patents.
Patent US4501636A successfully refreshed from Google Patents.
US4501636A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for etching vertical junction solar cell wafers
Assignee: United States Department of the Air Force
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Filing: 1983-12-28
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Granted: 1985-02-26
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Expires: 2003-12-28
Abstract
Abstract An apparatus for etching semiconductor wafers which comprises a cylindrical vessel with a lid having associated cooling means, a basket assembly, rack means for holding a plurality of wafers, support means for supporting the basket assembly above the bottom of the vessel, and stirring means.
Inventors
- 👤 Charles R. Valley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 08:47
CPC Classifications
C; C23; C23F; C23F1/00; C23F1/08
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
149 words
An apparatus for etching semiconductor wafers which consists essentially of, in operable association, a. a cylindrical vessel having a closed bottom and an open tap; b. a lid for said vessel, said lid having cooling means in association therewith and having means for holding a temperature sensor; c. a basket assembly adapted for positioning within said cylindrical vessel, said basket assembly having a porous bottom and a porous side and an open top and having handle means in association therewith for lowering said assembly into said vessel and for removing said assembly from said vessel; d. support means for supporting said basket assembly above the inside bottom of said vessel to provide a free space between the bottom of said vessel and the bottom of said assembly; e. rack means in association with said basket assembly for holding a plurality of semiconductor wafers for etching; and f. stirring means.
Claim 2
Independent Claim
149 words
An apparatus for etching semiconductor wafers which consists essentially of, in operable association, a. a cylindrical vessel having a closed bottom and an open tap; b. a lid for said vessel, said lid having cooling means in association therewith and having means for holding a temperature sensor; c. a basket assembly adapted for positioning within said cylindrical vessel, said basket assembly having a porous bottom and a porous side and an open top and having handle means in association therewith for lowering said assembly into said vessel and for removing said assembly from said vessel; d. support means for supporting said basket assembly above the inside bottom of said vessel to provide a free space between the bottom of said vessel and the bottom of said assembly; e. rack means in association with said basket assembly for holding a plurality of semiconductor wafers for etching; and f. stirring means.
References Cited (Backward Citations)
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US3985579A
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US4155866A
Cited
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Cited
US4227942A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-02-26 | 1988-08-27 | 1989-02-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-02-26 | 1992-08-27 | 1993-02-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-02-26 | 1996-08-27 | 1997-02-26 | $7700.00 | Window Closed / Lapsed |