US3012920A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process of selective etching with resist preparation
Assignee: AT&T Inc
•
Filing: 1959-01-05
•
Granted: 1961-12-12
•
Expires: 1979-01-05
Abstract
No abstract record available.
Inventors
- 👤 Christensen Howard
- 👤 Walter S Noll
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 18:20
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/69; H10P50/691; H10P50/692
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
49 words
THE METHOD OF SELECTIVELY ETCHING A CRYSTALLINE SEMICONDUCTIVE SURFACE WHICH COMPRISES APPLYING AN ADHERENT COATING TO AN AREA NOT TO BE ETCHED, APPLYING AN ETCHING RESIST LAYER UPON THE SAID ADHERENT COATING, SUBJECTING THE SAID SEMICONDUCTIVE SURFACE TO AN ETCHANT AND REMOVING THE RESIST BY DISSOLVING THE ADHERENT COATING.
Claim 2
Independent Claim
49 words
THE METHOD OF SELECTIVELY ETCHING A CRYSTALLINE SEMICONDUCTIVE SURFACE WHICH COMPRISES APPLYING AN ADHERENT COATING TO AN AREA NOT TO BE ETCHED, APPLYING AN ETCHING RESIST LAYER UPON THE SAID ADHERENT COATING, SUBJECTING THE SAID SEMICONDUCTIVE SURFACE TO AN ETCHANT AND REMOVING THE RESIST BY DISSOLVING THE ADHERENT COATING.
References Cited (Backward Citations)
US2780569A
Cited
US2879147A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-12-11 | 1965-06-12 | 1965-12-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-12-11 | 1969-06-12 | 1969-12-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-12-11 | 1973-06-12 | 1973-12-12 | $7700.00 | Window Closed / Lapsed |