US3568012A
Expired / Lapsed
US
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A microminiature circuit device employing a low thermal expansion binder
Assignee: Westinghouse Electric Corp
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Filing: 1968-11-05
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Granted: 1971-03-02
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Expires: 1988-11-05
Abstract
Abstract A low thermal expansion insulating cement is formulated from a high temperature resinous varnish and a finely divided inert inorganic filler having a negative coefficient of thermal expansion. The composition is employed as an insulator and binder in microminiature circuit devices employing microminiature circuit elements.
Inventors
- 👤 Wentworth A Ernst
- 👤 Charles W Wyble
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 07:02
CPC Classifications
H; H01; H01B; H01B3/00; H01B3/18; H01B3/30; H01B3/42; C; C08; C08L; C08L79/00; C08L79/04; C08L79/08; H01B3/307; H10; H10W; H10W70/00; H10W70/60; H10W70/099; H10W70/67; H10W70/68; H10W70/682; H10W72/00; H10W72/071; H10W72/073; H10W72/851; H10W72/874; H10W72/884; H10W90/00; H10W90/701; H10W90/751; H10W90/754
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
64 words
A microminiature circuit device comprising a substrate, thin film circuitry on said substrate, a plurality of microminiature elements mounted on the substrate, a high temperature resinous cement containing a finely divided inner filler having a negative coefficient of thermal expansion bonding the microminiature element onto the substrate, and a plurality of metallic interconnection conductors running from the microminiature elements to the thin film circuitry.
Claim 2
Dependent Claim
64 words
A microminiature circuit device comprising a substrate, thin film circuitry on said substrate, a plurality of microminiature elements mounted on the substrate, a high temperature resinous cement containing a finely divided inner filler having a negative coefficient of thermal expansion bonding the microminiature element onto the substrate, and a plurality of metallic interconnection conductors running from the microminiature elements to the thin film circuitry.
Claim 3
Dependent Claim
75 words
The device of claim 1 wherein the substrate has a plurality of hollow cavities therein, the microminiature elements are mounted in said cavities so that they are recessed and spaced from the cavity surfaces, the cement bonding the microminiature elements into the cavities, spacing the elements from the cavity surface and forming a bridge from the microminiature elements to the thin film circuitry and the plurality of interconnection conductors are deposited over the cement bridge.
Claim 4
Dependent Claim
54 words
The device of claim 1 wherein the cement comprises a resinous varnish containing a resin selected from the group consisting of aromatic polyimides, aromatic polyamide-imides, methylene bridged diphenyl oxides, an inert finely divided inorganic filler selected from the group consisting of Li2O Al2O3 8SiO2, Li2O Al2O3 4SiO2, Li20 A1203 2SiO2 and a thixotroping agent.
Claim 5
Dependent Claim
51 words
The device of claim 1 wherein the plurality of metal interconnection conductors are selected from the group consisting of gold, aluminum, silver, copper and base alloys thereof and wherein the substrate is selected from the group consisting of soda lime glass, borosilicate glass, fused silica glass, aluminum oxide and beryllium oxide.
Claim 6
Dependent Claim
37 words
The device of claim 1 wherein the microminiature element is a silicon microdot chip semiconductor, the metallic interconnection conductors are gold, the substrate is aluminum oxide, and the resinous varnish contains the resin methylene bridged diphenyl oxide.
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) | 1974-03-01 | 1974-08-31 | 1975-03-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-03-01 | 1978-08-31 | 1979-03-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-03-01 | 1982-08-31 | 1983-03-02 | $7700.00 | Window Closed / Lapsed |