US3107188A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process of etching semiconductors and etchant solutions used therefor
Assignee: Pacific Semiconductors Inc
•
Filing: 1960-11-21
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Granted: 1963-10-15
•
Expires: 1980-11-21
Abstract
No abstract record available.
Inventors
- 👤 Robert D Hancock
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 20:16
CPC Classifications
H; H10; H10P; H10P70/00; H10P70/10; H10P70/15; H10P50/00; H10P50/20; H10P50/28; H10P50/282; H10P50/283; H10P50/60; H10P50/64; H10P50/642
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
65 words
THE PROCESS OF REMOVING OXIDES FROM A SEIMICONDUCTOR SURFACE WHICH COMPRISES THE STEP OF APPLYING TO SAID OXIDES AN AQUEOUS SOLUTION OF HYDROFLUORIC ACID, PHOSPHORIC ACID AND AMMONIUM BIFLUORIDE, SAID SOLUTION CORRESPONDING TO A MOLAR RATIO WITHIN THE RANGE OF FROM 1.5 TO 4 MOLES HYDROGEN FLUORIDE; 1.5 TO 4 MOLES WATER; 1 TO 3.5 MOLES PHOSPHORIC ACID; AND 1 TO 3.5 MOLES AMMONIUM BIFLUORIDE.
Claim 2
Dependent Claim
65 words
THE PROCESS OF REMOVING OXIDES FROM A SEIMICONDUCTOR SURFACE WHICH COMPRISES THE STEP OF APPLYING TO SAID OXIDES AN AQUEOUS SOLUTION OF HYDROFLUORIC ACID, PHOSPHORIC ACID AND AMMONIUM BIFLUORIDE, SAID SOLUTION CORRESPONDING TO A MOLAR RATIO WITHIN THE RANGE OF FROM 1.5 TO 4 MOLES HYDROGEN FLUORIDE; 1.5 TO 4 MOLES WATER; 1 TO 3.5 MOLES PHOSPHORIC ACID; AND 1 TO 3.5 MOLES AMMONIUM BIFLUORIDE.
Claim 3
Dependent Claim
59 words
AN ETCHANT FOR REMOVING OXIDES FROM A SEMICONDUCTOR SURFACE, SAID ETCHANT CONSISTING OF AN AQUEOUS SOLUTION OF HYDROFLUORIC ACID, PHOSPHORIC ACID AND AMMONIUM BIFLUORIDE WHICH CORRESPONDS TO A MOLAR RATIO WITHIN THE RANGE OF FROM 1.5 TO 4 MOLES HYDROGEN FLUORIDE; 1.5 TO 4 MOLES WATER; 1 TO 3.5 MOLES PHOSPHORIC ACID; AND 1 TO 3.5 MOLES AMMONIUM BIFLUORIDE.
Claim 4
Dependent Claim
59 words
AN ETCHANT FOR REMOVING OXIDES FROM A SEMICONDUCTOR SURFACE, SAID ETCHANT CONSISTING OF AN AQUEOUS SOLUTION OF HYDROFLUORIC ACID, PHOSPHORIC ACID AND AMMONIUM BIFLUORIDE WHICH CORRESPONDS TO A MOLAR RATIO WITHIN THE RANGE OF FROM 1.5 TO 4 MOLES HYDROGEN FLUORIDE; 1.5 TO 4 MOLES WATER; 1 TO 3.5 MOLES PHOSPHORIC ACID; AND 1 TO 3.5 MOLES AMMONIUM BIFLUORIDE.
References Cited (Backward Citations)
US2376219A
Cited
US2419237A
Cited
US2411298A
Cited
US2462218A
Cited
US2593449A
Cited
US2705392A
Cited
US2876144A
Cited
US2847287A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1966-10-14 | 1967-04-15 | 1967-10-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1970-10-14 | 1971-04-15 | 1971-10-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1974-10-14 | 1975-04-15 | 1975-10-15 | $7700.00 | Window Closed / Lapsed |