Patent US3203434A successfully refreshed from Google Patents.
US3203434A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Chemical polishing machine
Assignee: AT&T Inc
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Filing: 1963-12-06
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Granted: 1965-08-31
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Expires: 1983-12-06
Abstract
No abstract record available.
Inventors
- 👤 Karl F Kipp
- 👤 Joseph A Santangini
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 14:06
CPC Classifications
C; C23; C23F; C23F1/00; C23F1/08; C23F3/00
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
85 words
IN A CHEMICAL POLISHING MACHINE FOR A SILICON SLICE, A TANK FOR RECEIVING AN ETCHANT SOLUTION THAT REACTS WITH SILICON AND RISES IN TEMPERATURE IN ACCORDANCE WITH THE EXTEND OF ETCHING OF THE SILICON, MEANS FOR SUPPORTING A SILICON SLICE IN SAID TANK, NORMALLY UNOPERATED MEANS FOR MOVING THE SUPPORTING MEANS TO WITHDRAW THE SLICE FROM THE TANK, AND MEANS RESPONSIVE TO A PREDETERMINED TEMPERATURE RISE IN THE ETCHANT SOLUTION FOR OPEATING SAID MOVING MEANS TO WITHDRAW THE SUPPORTING MEANS AND SLICE FROM THE TANK.
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) | 1968-08-30 | 1969-03-01 | 1969-08-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-08-30 | 1973-03-01 | 1973-08-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-08-30 | 1977-03-01 | 1977-08-31 | $7700.00 | Window Closed / Lapsed |