US2953438A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat treatment of silicon
Assignee: The General Electric Company PLC
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Filing: 1958-12-03
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Granted: 1960-09-20
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Expires: 1978-12-03
Abstract
No abstract record available.
Inventors
- 👤 Dale Brian
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 00:59
CPC Classifications
C; C22; C22F; C22F1/00; C22F1/16; C01; C01B; C01B33/00; C01B33/02; H; H10; H10P; H10P95/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
69 words
A METHOD OF HEAT TREATING SILICON HAVING A MINORITY CARRIER LIFETIME GREATER THAN ONE MICROSECOND, CONSISTING IN CARRYING OUT AT LEAST ONCE THE STEPS OF HEATING THE SILICON TO A TEMPERATURE GREATER THAN 1100*C. BUT BELOW ITS MELTING POINT, AND THEN COOLING THE SILICCON TO A TEMPERATURE BELOW 800*C. IN SUCH A MANNER THAT THE SILICON TRAVERSES THE TEMPERATURE RANGE BETWEEN 1100*C. AND 800*C. IN LESS THAN 0.3 SECOND.
Claim 2
Independent Claim
69 words
A METHOD OF HEAT TREATING SILICON HAVING A MINORITY CARRIER LIFETIME GREATER THAN ONE MICROSECOND, CONSISTING IN CARRYING OUT AT LEAST ONCE THE STEPS OF HEATING THE SILICON TO A TEMPERATURE GREATER THAN 1100*C. BUT BELOW ITS MELTING POINT, AND THEN COOLING THE SILICCON TO A TEMPERATURE BELOW 800*C. IN SUCH A MANNER THAT THE SILICON TRAVERSES THE TEMPERATURE RANGE BETWEEN 1100*C. AND 800*C. IN LESS THAN 0.3 SECOND.
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) | 1963-09-20 | 1964-03-21 | 1964-09-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-09-20 | 1968-03-21 | 1968-09-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-09-20 | 1972-03-21 | 1972-09-20 | $7700.00 | Window Closed / Lapsed |