Patent US2844639A successfully refreshed from Google Patents.
US2653085A
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Etching solution and process
Assignee: Westinghouse Electric Corp
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Filing: 1952-08-09
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Granted: 1953-09-22
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Expires: 1972-08-09
Abstract
No abstract record available.
Inventors
- 👤 Jr Richard H Wynne
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 16:09
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/60; H10P50/64; H10P50/642; C; C09; C09K; C09K13/00; C09K13/04; C09K13/08; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12993; Y10T428/24; Y10T428/24479
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
43 words
THE PROCESS OF PREPARING THE SURFACE OF A BODY OF GERMANIUM FOR USE IN A SEMICONDUCTOR DEVICE WHICH COMPRISES ETCHING SAID SURFACE IN AN AQUEOUS SOLUTION OF HYDROFLUORIC ACID, NITRIC ACID, AND SILVER NITRATE, AND THEN WASHING SAID ETCHING SOLUTION FROM SAID SURFACE.
Claim 2
Dependent Claim
43 words
THE PROCESS OF PREPARING THE SURFACE OF A BODY OF GERMANIUM FOR USE IN A SEMICONDUCTOR DEVICE WHICH COMPRISES ETCHING SAID SURFACE IN AN AQUEOUS SOLUTION OF HYDROFLUORIC ACID, NITRIC ACID, AND SILVER NITRATE, AND THEN WASHING SAID ETCHING SOLUTION FROM SAID SURFACE.
Claim 3
Dependent Claim
80 words
THE PRROCESS OF CLAIM 1 WHEREIN THE PROPORTIONS OF INGREDIENTS PRESENT IN 100 PARTS BY WEIGHT OF ETCHING SOLUTION COMPRISES A MIXTURE OF FROM 50% TO 86% BY WEIGHT OF WATER AND FROM 14% TO 50% BY WEIGHT OF ACIDS, THE ACIDS BEING PRESENT IN RATIOS OF HF TO HNO3 OF FROM 6:1 TO 1:16 BY WEIGHT, AND SILVER NITRATE BEING DISSOLVED IN THE SOLUTION IN AN AMOUNT OF AT LEAST 1% OF THE WEIGHT OF THE AQUEOUS ACID SOLUTION.
References Cited (Backward Citations)
US2514879A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-09-21 | 1957-03-23 | 1957-09-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-09-21 | 1961-03-23 | 1961-09-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-09-21 | 1965-03-23 | 1965-09-22 | $7700.00 | Window Closed / Lapsed |