US4820376A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fabrication of CPI layers
Assignee: Nokia Bell Labs
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Filing: 1987-11-05
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Granted: 1989-04-11
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Expires: 2007-11-05
Abstract
Abstract Disclosed is a method of fabricating conductive polymer interconnect (CPI) material which employs chains of electrically conductive particles within an elastomeric matrix. Contact resistance is improved by removing a thin layer is elastomeric material which remains after normal processing. The surface layer is removed by plasma etching so that the conductive particles protrude at both surfaces. The protruding particles can be plated to replace any conductive material removed by the etch.
Inventors
- 👤 William R. Lambert
- 👤 Neng-hsing Lu
- 👤 Ray D. Rust
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 22:30
CPC Classifications
H; H01; H01R; H01R13/00; H01R13/02; H01R13/22; H01R13/24; H01R13/2407; H01R13/2414; B; B29; B29C; B29C70/00; B29C70/04; B29C70/28; B29C70/54; B29C70/545; B29C70/58; B29C70/64; B29C70/88; B29C70/882; H10; H10W; H10W70/00; H10W70/20; H10W70/22; H10W70/60; H10W70/62; H10W70/63; H10W70/635; B29K; B29K2995/00; B29K2995/0003; B29K2995/0005; H10W72/00; H10W72/30; H10W72/321; H10W72/325; H10W72/351; H10W72/352; H10W72/353; H10W72/354; Y; Y10; Y10T; Y10T428/00; Y10T428/25; Y10T428/256; Y10T428/257
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
61 words
A method of fabricating a layer of silicone elastomer material including chains of electrically conducting particles extending essentially perpendicular to the major surfaces of the layer, the method comprising the step of removing a portion of at least one of said major surfaces by plasma etching so that the particles at the ends of said chains protrude through the etched surface.
Claim 2
Independent Claim
61 words
A method of fabricating a layer of silicone elastomer material including chains of electrically conducting particles extending essentially perpendicular to the major surfaces of the layer, the method comprising the step of removing a portion of at least one of said major surfaces by plasma etching so that the particles at the ends of said chains protrude through the etched surface.
Claim 3
Dependent Claim
30 words
The method according to claim 1 further comprising the step of subjecting the layer to an electroless plating operation to restore any conducting material removed during the plasma etching operation.
Claim 4
Dependent Claim
33 words
The method according to claim 2 wherein the conducting particles comprise an inner conducting core and an outer conducting coating, and the plating operation restores the outer conducting coating of the protruding particles.
Claim 5
Dependent Claim
28 words
The method according to claim 3 wherein the inner core comprises nickel and the outer coating comprises a material selected from the group consisting of gold and silver.
Claim 6
Dependent Claim
22 words
The method according to claim 1 wherein the plasma etching employs a gas consisting essentially of CF 4 and O 2 .
Claim 7
Dependent Claim
22 words
The method according to claim 5 wherein the gas composition is 72.5-75.5 percent CF 4 with the balance being O 2 .
Claim 8
Dependent Claim
19 words
The method according to claim 6 wherein the flow rate of the gas is within the range 156-164 sccm.
Claim 9
Dependent Claim
19 words
The method according to claim 1 wherein the particles protrude an average distance of approximately one-half the particle diameter.
Claim 10
Dependent Claim
19 words
The method according to claim 1 wherein a surface portion of both major surfaces is removed by plasma etching.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-04-10 | 1992-10-10 | 1993-04-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-04-10 | 1996-10-10 | 1997-04-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-04-10 | 2000-10-10 | 2001-04-11 | $7700.00 | Window Closed / Lapsed |