Patent US2861931A successfully refreshed from Google Patents.
US2861931A
Expired / Lapsed
US
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Electrolytic etching processes
Assignee: Westinghouse Electric Corp
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Filing: 1956-08-29
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Granted: 1958-11-25
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Expires: 1976-08-29
Abstract
No abstract record available.
Inventors
- 👤 Jr John W Faust
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 23:31
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/60; H10P50/61; H10P50/613; C; C25; C25F; C25F3/00; C25F3/02; C25F3/12
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
74 words
IN THE PROCESS OF ETCHING SILICON, THE STEPS OF MECHANICALLY POLISHING THE SOLUTION TO REMOVE DELETERIOUS MATTER FROM THE SURFACE, APPLYING TO THE SILICON AN ELECTROLYTE COMPRISING ONLY A MIXTURE OF FROM 1% TO 30% BY VOLUME OF CONCENTRATED HYDROFLUORIC ACID AND THE BALANCE BEING AN ANHYDROUS HYDROPHILIC SOLVENT COMPRISING AT LEAST ONE SELECTED FROM THE GROUP CONSISTING OF MONOHYDRIC AND POLYHYDRIC ALCOHOLS, ETHERS, CARBOXYLIC ACIDS, AMINES, ESTERS AND KETONES, AND CAUSING AN ELECTRIC
Claim 2
Dependent Claim
74 words
IN THE PROCESS OF ETCHING SILICON, THE STEPS OF MECHANICALLY POLISHING THE SOLUTION TO REMOVE DELETERIOUS MATTER FROM THE SURFACE, APPLYING TO THE SILICON AN ELECTROLYTE COMPRISING ONLY A MIXTURE OF FROM 1% TO 30% BY VOLUME OF CONCENTRATED HYDROFLUORIC ACID AND THE BALANCE BEING AN ANHYDROUS HYDROPHILIC SOLVENT COMPRISING AT LEAST ONE SELECTED FROM THE GROUP CONSISTING OF MONOHYDRIC AND POLYHYDRIC ALCOHOLS, ETHERS, CARBOXYLIC ACIDS, AMINES, ESTERS AND KETONES, AND CAUSING AN ELECTRIC
References Cited (Backward Citations)
US2686279A
Cited
US2656496A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-11-24 | 1962-05-26 | 1962-11-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-11-24 | 1966-05-26 | 1966-11-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-11-24 | 1970-05-26 | 1970-11-25 | $7700.00 | Window Closed / Lapsed |