US3783048A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High frequency transistor fabrication
Assignee: Harris Corp
•
Filing: 1972-03-22
•
Granted: 1974-01-01
•
Expires: 1992-03-22
Abstract
Abstract IN THE FABRICATION OF HIGH FREQUENCY NPN TRANSISTORS IN INTEGERATED CIRCUITS, A DOPED OXIDE LAYER IS FORMED ON THE SURFACE OF THE WATER AFTER DIFFUSION OF THE BASE REGION AND PRIOR TO OPENING THE EMITTER DIFFUSION WINDOW. THEREAFTER, REMOVAL OF OXIDE REGROWN IN THE EMITTER DIFFUSION WINDOW TO FORM AN EMITTER CONTACT WINDOW, AND SIMULTANEOUS REMOVAL OF OTHER SURFACE OXIDE CONCURRENTLY GROWTH THEREWITH, LEAVES INTACT THE DOPED OXIDE LAYER TO PREVENT SURFACE INVERSION.
Inventors
- 👤 T Sanders
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 06:33
CPC Classifications
H; H10; H10W; H10W74/00; H10W74/40; H10W74/43; H10P; H10P95/00; H10W74/10; H10W74/131
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1976-12-31 | 1977-07-02 | 1978-01-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-31 | 1981-07-02 | 1982-01-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-31 | 1985-07-02 | 1986-01-01 | $7700.00 | Window Closed / Lapsed |