Patent US3632436A successfully refreshed from Google Patents.
US3632436A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Contact system for semiconductor devices
Assignee: RCA Corp
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Filing: 1969-07-11
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Granted: 1972-01-04
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Expires: 1989-07-11
Abstract
Abstract A method of providing a silicon semiconductor device having an oxide passivation layer, with a nickel-lead (NiPb) contact system comprising: depositing either an epitaxial layer or a polycrystalline layer of silicon on top of the oxide layer in the desired contact pattern, depositing a thin film of nickel electrolessly on the silicon layer but not on the oxide, and depositing a layer of lead solder on the silicon layer but not on the oxide layer.
Inventors
- 👤 Richard Denning
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 22:53
CPC Classifications
H; H10; H10W; H10W99/00; H10P; H10P14/00; H10P14/40; H10P14/46; H10P95/00; H10W20/00; H10W20/40
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
25 words
A method according to claim 1 in which said silicon layer is polycrystalline and said lead includes a portion in contact with said silicon body.
Claim 2
Independent Claim
146 words
A method of making ohmic contact to a silicon semiconductor body comprising depositing a first layer of silicon dioxide on a surface of said body, removing part of said first silicon dioxide layer thereby exposing a part of said surface where ohmic contact is desired, depositing a layer of silicon on both the remaining portion of said first silicon dioXide layer and said exposed surface portion, depositing a second layer of silicon dioxide on said silicon layer, removing a portion of said second silicon dioxide layer thereby exposing a portion of said silicon layer, etching away said exposed portion of said silicon layer and exposing a portion of said silicon body, removing the remaining portion of said silicon dioxide layer, depositing nickel electrolessly on the remaining portion of said silicon layer, and exposed portion of the silicon body, and depositing lead solder on said deposited nickel.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-01-03 | 1975-07-05 | 1976-01-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-03 | 1979-07-05 | 1980-01-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-03 | 1983-07-05 | 1984-01-04 | $7700.00 | Window Closed / Lapsed |