Patent US5692923A successfully refreshed from Google Patents.
US3846196A
Expired / Lapsed
US
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Technique for selective etching of gold and etchant therefor
Assignee: AT&T Inc
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Filing: 1974-03-14
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Granted: 1974-11-05
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Expires: 1994-03-14
Abstract
Abstract 1. A TECHNIQUE FOR THE SELECTIVE ETCHING OF GOLD IN THE PRESENCE OF PALLADIUM WHICH COMPRISES IMMERSING A STRUCTURE INCLUDING GOLD AND PALLADIUM PATTERNED WITH A RESIST IN AN ETCHANT SOLUTION HAVING A PH GREATER THAN 10 COMPRISING A FERRICYANIDE SOLUTION HAVING A MOLARITY WITHIN THE RANGE OF 0.01 TO 1 AND A CYANIDE SOLUTION IN A STRONG BASE HAVING A MOLARITY WITHIN THE RANGE OF 0.01 TO 0.5.
Inventors
- 👤 D Macarthur
- 👤 P Skurkiss
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 17:46
CPC Classifications
H; H10; H10P; H10P95/00; C; C23; C23F; C23F1/00; C23F1/10; C23F1/14; C23F1/32; C23F1/40; H10N; H10N97/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
68 words
A TECHNIQUE FOR THE SELECTIVE ETCHING OF GOLD IN THE PRESENCE OF PALLADIUM WHICH COMPRISES IMMERSING A STRUCTURE INCLUDING GOLD AND PALLADIUM PATTERNED WITH A RESIST IN AN ETCHANT SOLUTION HAVING A PH GREATER THAN 10 COMPRISING A FERRICYANIDE SOLUTION HAVING A MOLARITY WITHIN THE RANGE OF 0.01 TO 1 AND A CYANIDE SOLUTION IN A STRONG BASE HAVING A MOLARITY WITHIN THE RANGE OF 0.01 TO 0.5.
Claim 2
Dependent Claim
68 words
A TECHNIQUE FOR THE SELECTIVE ETCHING OF GOLD IN THE PRESENCE OF PALLADIUM WHICH COMPRISES IMMERSING A STRUCTURE INCLUDING GOLD AND PALLADIUM PATTERNED WITH A RESIST IN AN ETCHANT SOLUTION HAVING A PH GREATER THAN 10 COMPRISING A FERRICYANIDE SOLUTION HAVING A MOLARITY WITHIN THE RANGE OF 0.01 TO 1 AND A CYANIDE SOLUTION IN A STRONG BASE HAVING A MOLARITY WITHIN THE RANGE OF 0.01 TO 0.5.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-11-04 | 1978-05-06 | 1978-11-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-11-04 | 1982-05-06 | 1982-11-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-11-04 | 1986-05-06 | 1986-11-05 | $7700.00 | Window Closed / Lapsed |