Patent US3930193A successfully refreshed from Google Patents.
US2827367A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Etching of semiconductor materials
Assignee: Texas Instruments Inc
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Filing: 1955-08-30
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Granted: 1958-03-18
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Expires: 1975-08-30
Abstract
No abstract record available.
Inventors
- 👤 Douglas L Cox
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 02:39
CPC Classifications
C; C23; C23F; C23F1/00; C09; C09K; C09K13/00; C09K13/04; C09K13/08; H; H10; H10P; H10P95/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
60 words
A METHOD OF ETCHING ELECTRICAL SEMICONDUCTORS THAT COMPRISES TREATING THE SURFACE OF THE SEMICONDUCTOR WITH AN ETCHING SOLUTION CONTAINING NITRIC ACID, HYDROFLUORIC ACID AND POTASSIUM IODIDE IN THE PROPORTIONS OF 300 ML. OF CONCENTRATED NITRIC ACID, TO APPROXIMATELY 160 TO 220 ML. OF 48% HYDROFLUORIC ACID, TO APPROXIMATELY 50 TO 200 DROPS OF 1% POTASSIUM IODIDE SOLUTION IN DISTILLED WATER.
Claim 2
Independent Claim
60 words
A METHOD OF ETCHING ELECTRICAL SEMICONDUCTORS THAT COMPRISES TREATING THE SURFACE OF THE SEMICONDUCTOR WITH AN ETCHING SOLUTION CONTAINING NITRIC ACID, HYDROFLUORIC ACID AND POTASSIUM IODIDE IN THE PROPORTIONS OF 300 ML. OF CONCENTRATED NITRIC ACID, TO APPROXIMATELY 160 TO 220 ML. OF 48% HYDROFLUORIC ACID, TO APPROXIMATELY 50 TO 200 DROPS OF 1% POTASSIUM IODIDE SOLUTION IN DISTILLED WATER.
References Cited (Backward Citations)
US2708184A
Cited
US2705192A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-03-17 | 1961-09-16 | 1962-03-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-03-17 | 1965-09-16 | 1966-03-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-03-17 | 1969-09-16 | 1970-03-18 | $7700.00 | Window Closed / Lapsed |