US2768914A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing semiconductive crystals of uniform resistivity
Assignee: AT&T Inc
•
Filing: 1951-06-29
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Granted: 1956-10-30
•
Expires: 1971-06-29
Abstract
No abstract record available.
Inventors
- 👤 Buehler Ernest
- 👤 Gordon K Teal
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:47
CPC Classifications
C; C30; C30B; C30B15/00; H; H10; H10P; H10P90/00; H10P90/12; C30B13/00; C30B15/02; C30B15/04; C30B29/00; C30B29/02; C30B29/06; Y; Y10; Y10S; Y10S438/00; Y10S438/914; Y10S438/925
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
136 words
THE METHOD OF PRODUCING A CRYSTAL OF NORMALLY SOLID SEMICONDUCTIVE MATERIAL CONTAINING A SIGNIFICANT IMPURITY HAVING A T OF LESS THAN 1 COMPRISING INSERTING A SEED INTO A MELT OF THE SAID SEMICONDUCTIVE MATERIAL CONTAINING THE SAID SIGNIFICANT IMPURITY, AND WITHDRAWING THE SAID SEED AT A DECREASING WITHDRAWAL RATE SUCH AS TO SUBSTANTIALLY COMPENSATE FOR THE RESULTING INCREASING CONCENTRATION OF THE SAID SIGNIFICANT IMPURITY IN THE MELT AND SUCH AS TO PRODUCE A CRYSTAL MANIFESTING SUBSTANTIALLY UNIFORM RESISTIVITY OVER THAT PORTION OF THE CRYSTAL PRODUCED WHILE DECREASING THE WITHDRAWAL RATE, THE RATE OF WITHDRAWAL BEING AT ALL TIMES SUCH AS TO MAINTAIN A SOLID-LIQUID INTERFACE BETWEEN THE CRYSTAL AND THE MELT, T BEING DEFINED AS THE RATIO OF IMPURITY CONCENTRATION IN THE SOLID TO THE IMPURITY CONCENTRATION IN THE LIQUID WITH THE TWO PHASES AT EQUILIBRIUM.
Claim 2
Independent Claim
136 words
THE METHOD OF PRODUCING A CRYSTAL OF NORMALLY SOLID SEMICONDUCTIVE MATERIAL CONTAINING A SIGNIFICANT IMPURITY HAVING A T OF LESS THAN 1 COMPRISING INSERTING A SEED INTO A MELT OF THE SAID SEMICONDUCTIVE MATERIAL CONTAINING THE SAID SIGNIFICANT IMPURITY, AND WITHDRAWING THE SAID SEED AT A DECREASING WITHDRAWAL RATE SUCH AS TO SUBSTANTIALLY COMPENSATE FOR THE RESULTING INCREASING CONCENTRATION OF THE SAID SIGNIFICANT IMPURITY IN THE MELT AND SUCH AS TO PRODUCE A CRYSTAL MANIFESTING SUBSTANTIALLY UNIFORM RESISTIVITY OVER THAT PORTION OF THE CRYSTAL PRODUCED WHILE DECREASING THE WITHDRAWAL RATE, THE RATE OF WITHDRAWAL BEING AT ALL TIMES SUCH AS TO MAINTAIN A SOLID-LIQUID INTERFACE BETWEEN THE CRYSTAL AND THE MELT, T BEING DEFINED AS THE RATIO OF IMPURITY CONCENTRATION IN THE SOLID TO THE IMPURITY CONCENTRATION IN THE LIQUID WITH THE TWO PHASES AT EQUILIBRIUM.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1959-10-30 | 1960-04-30 | 1960-10-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-10-30 | 1964-04-30 | 1964-10-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-10-30 | 1968-04-30 | 1968-10-30 | $7700.00 | Window Closed / Lapsed |