Patent US3647935A successfully refreshed from Google Patents.
US3647935A
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US
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Intermetallic passivation of aluminum metallization
Assignee: Motorola Solutions Inc
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Filing: 1969-12-15
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Granted: 1972-03-07
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Expires: 1989-12-15
Abstract
Abstract An electrically conductive intermetallic coating which is resistant to corrosion serves as a passivating layer on an aluminum metallization. The preferred intermetallic is AuA12. The intermetallic passivating layer protects the aluminum metallization from chemical attack thereby increasing device lifetime and stability.
Inventors
- 👤 Elliott M Philofsky
- 👤 Kim Ritchie
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 23:37
CPC Classifications
H; H10; H10P; H10P95/00; H10P95/50; H10W; H10W74/00; H10W74/10
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
25 words
A method as disclosed in claim 1 wherein the step of depoSiting said gold is depositing gold to a thickness of 1,000 to 2,000 angstroms.
Claim 2
Dependent Claim
27 words
A method as described in claim 1 wherein the step of heating said gold deposited aluminum metallization is heating to a temperature of 200* to 400* C.
Claim 3
Dependent Claim
46 words
A semiconductor device comprising a semiconductor substrate, an exposed aluminum metallization positioned on said substrate, and a layer of an electrically conductive intermetallic AuA12 on and covering all of said exposed aluminum metallization, said conducting intermetallic being relatively inert to corrosion caused by the chloride ion.
Claim 4
Dependent Claim
21 words
A device as disclosed in claim 4 wherein an insulative layer is interposed between said aluminum metallization and said semiconductor substrate.
References Cited (Backward Citations)
US3436615A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-03-07 | 1975-09-06 | 1976-03-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-03-07 | 1979-09-06 | 1980-03-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-03-07 | 1983-09-06 | 1984-03-07 | $7700.00 | Window Closed / Lapsed |