US3644097A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for control of heat radiation in zone melting
Assignee: Individual
•
Filing: 1968-11-13
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Granted: 1972-02-22
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Expires: 1988-11-13
Abstract
Abstract Control of heat radiation from the ''''critical zone'''' adjacent the molten material in a floating-zone purification of a semiconductor monocrystal to achieve a low level of dislocations.
Inventors
- 👤 Poul E Knudsen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 14:29
CPC Classifications
C; C30; C30B; C30B13/00; C30B13/28; Y; Y10; Y10T; Y10T117/00; Y10T117/10; Y10T117/1024; Y10T117/1076; Y10T117/1088
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-02-21 | 1975-08-23 | 1976-02-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-02-21 | 1979-08-23 | 1980-02-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-02-21 | 1983-08-23 | 1984-02-22 | $7700.00 | Window Closed / Lapsed |