US3223493A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of crucible-free zone-melting of semiconductor material
Assignee: Siemens Schuckertwerke AG
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Filing: 1961-06-09
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Granted: 1965-12-14
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Expires: 1981-06-09
Abstract
No abstract record available.
Inventors
- 👤 Keller Wolfgang
- 👤 Kramer Herbert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 10:05
CPC Classifications
C; C30; C30B; C30B13/00; Y; Y10; Y10S; Y10S117/00; Y10S117/906
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
79 words
IN THE METHOD OF CRUCIBLE-FREE ZONE-MELTING OF SILICON SEMICONDUCTOR MATERIAL WHEREIN A ROD-SHAPED SEMICONDUCTOR BODY IS MOUNTED WITHIN A VACUUM VESSEL, SAID VESEL BEING EVACUATED, AND A HEATER WITHIN SAID VESSEL SERVES TO CAUSE A MOLTEN ZONE TO PASS REPEATEDLY THROUGH AND ALONG THE LENGTH OF SAID BODY BEING WITHIN SAID VESSEL, THE IMPROVEMENT WHICH COMPRISES THE STEPS OF INTRODUCING HUMID AIR INTO SAID VESSEL AFTER THE PENULTIMATE ZONE-MELTING PASS, RE-EVACUATING THE VESSEL AND PERFORMING THE LAST ZONE-MELTING PASS.
Claim 2
Dependent Claim
79 words
IN THE METHOD OF CRUCIBLE-FREE ZONE-MELTING OF SILICON SEMICONDUCTOR MATERIAL WHEREIN A ROD-SHAPED SEMICONDUCTOR BODY IS MOUNTED WITHIN A VACUUM VESSEL, SAID VESEL BEING EVACUATED, AND A HEATER WITHIN SAID VESSEL SERVES TO CAUSE A MOLTEN ZONE TO PASS REPEATEDLY THROUGH AND ALONG THE LENGTH OF SAID BODY BEING WITHIN SAID VESSEL, THE IMPROVEMENT WHICH COMPRISES THE STEPS OF INTRODUCING HUMID AIR INTO SAID VESSEL AFTER THE PENULTIMATE ZONE-MELTING PASS, RE-EVACUATING THE VESSEL AND PERFORMING THE LAST ZONE-MELTING PASS.
References Cited (Backward Citations)
US2901325A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-12-13 | 1969-06-14 | 1969-12-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-12-13 | 1973-06-14 | 1973-12-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-12-13 | 1977-06-14 | 1977-12-14 | $7700.00 | Window Closed / Lapsed |