US2993818A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for growing semiconductor crystals
Assignee: Texas Instruments Inc
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Filing: 1959-04-23
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Granted: 1961-07-25
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Expires: 1979-04-23
Abstract
No abstract record available.
Inventors
- 👤 Allen Chester Cameron
- 👤 Nunley William
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 15:29
CPC Classifications
C; C30; C30B; C30B15/00; C30B15/02; C30B15/04
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
143 words
THE METHOD FOR GROWING A PNP-TYPE TRANSISTOR CRYSTAL CHARACTERIZED BY A LAYER OF HIGH RESISTIVITY P-TYPE MATERIAL ADJACENT THE COLLECTOR-BASE JUNCTION WHICH COMPRISES THE STEPS OF GROWING AT A PREDETERMINED RATE A FIRST CRYSTAL REGION OF LOW RESISTIVITY P-TYPE CONDUCTIVITY FROM A MELT CONTAINING BOTH THE P-TYPE AND N-TYPE IMPURITIES WHEREIN SAID P-TYPE IMPURITY PREDOMINATES, SAID PTYPE IMPURITY BEING OF SUCH A CHARACTER THAT CHANGES IN CRYSTAL GROWTH RATE WILL CAUSE RELATIVELY LARGE CHANGES IN THE SEGREGATION COEFFICIENT OF SAID P-TYPE IMPURITY, CHANGING THE GROWTH RATE OF SAID CRYSTAL TO A FIXED LOWER RATE AND MAINTAINING THE GROWTH RATE AT SAID FIXED LOWER RATE WHILE GROWING A SECOND CRYSTAL REGION OF HIGH RESISTIVITY P-TYPE CONDUCTIVITY, ADDING AN ADDITIONAL QUANTITY OF NTYPE IMPURITY TO FORM A FIRST P-N JUNCTION, AND THEREAFTER ADDING AN ADDITIONAL QUANTITY OF P-TYPE IMPURITY TO FORM A SECOND P-N JUNCTION.
Claim 2
Independent Claim
143 words
THE METHOD FOR GROWING A PNP-TYPE TRANSISTOR CRYSTAL CHARACTERIZED BY A LAYER OF HIGH RESISTIVITY P-TYPE MATERIAL ADJACENT THE COLLECTOR-BASE JUNCTION WHICH COMPRISES THE STEPS OF GROWING AT A PREDETERMINED RATE A FIRST CRYSTAL REGION OF LOW RESISTIVITY P-TYPE CONDUCTIVITY FROM A MELT CONTAINING BOTH THE P-TYPE AND N-TYPE IMPURITIES WHEREIN SAID P-TYPE IMPURITY PREDOMINATES, SAID PTYPE IMPURITY BEING OF SUCH A CHARACTER THAT CHANGES IN CRYSTAL GROWTH RATE WILL CAUSE RELATIVELY LARGE CHANGES IN THE SEGREGATION COEFFICIENT OF SAID P-TYPE IMPURITY, CHANGING THE GROWTH RATE OF SAID CRYSTAL TO A FIXED LOWER RATE AND MAINTAINING THE GROWTH RATE AT SAID FIXED LOWER RATE WHILE GROWING A SECOND CRYSTAL REGION OF HIGH RESISTIVITY P-TYPE CONDUCTIVITY, ADDING AN ADDITIONAL QUANTITY OF NTYPE IMPURITY TO FORM A FIRST P-N JUNCTION, AND THEREAFTER ADDING AN ADDITIONAL QUANTITY OF P-TYPE IMPURITY TO FORM A SECOND P-N JUNCTION.
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) | 1964-07-24 | 1965-01-23 | 1965-07-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-07-24 | 1969-01-23 | 1969-07-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-07-24 | 1973-01-23 | 1973-07-25 | $7700.00 | Window Closed / Lapsed |