US3709746A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Double epitaxial method of fabricating a pedestal transistor
Assignee: International Business Machines Corp
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Filing: 1969-11-10
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Granted: 1973-01-09
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Expires: 1989-11-10
Abstract
Abstract A DOUBLE EPITAXIAL PROCESS FOR FORMING A PEDESTAL TRANSISTOR COMPRISING THE STEPS OF PROVIDING A SUBSTRATE OF A FIRST CONDUCTIVITY TYPE AND THEN FORMING FIRST AND SECOND OPPOSITE CONDUCTIVELY TYPE EPTAXIAL LAYERS THEREOVER. DURING THE GROWTH OF THE EPITAXIAL LAYERS, SELECTED OUT-DIFFUSIONS FROM THE EPITAXIAL LAYERS FROM A BURIED SUBCOLLECTOR AND PEDESTAL COLLECTOR REGION. DIFFUSED ISOLATION REGIONS AND BASE AND EMITTER REGIONS ARE FORMED TO COMPLETE THE DEVICE IN MONOLITHIC FORM. PRECISE THICKNESS AND CONCENTRATION CONTROL IN THE TOP EPITAXIAL LAYER AFFORDS OPTIMIZATION OR EXTRINSIC BASE-COLLECTOR CAPACITANCE.
Inventors
- 👤 Witt D De
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 14:45
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/01; H10W20/021; H10D; H10D99/00
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) | 1976-01-09 | 1976-07-10 | 1977-01-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-01-09 | 1980-07-10 | 1981-01-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-01-09 | 1984-07-10 | 1985-01-09 | $7700.00 | Window Closed / Lapsed |