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US4711804A Expired / Lapsed US ⏱️ 0.0 years remaining

Circuit board construction

Assignee: General Electric Co
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Filing: 1986-07-02
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Granted: 1987-12-08
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Expires: 2006-07-02
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Abstract

Abstract A circuit board assembly for supporting a leadless ceramic chip carrier for surface mounting on a printed circuit board and for reducing the thermally induced stress on solder joint connections at the carrier-to-board contacts. The board includes an inner heat sink core comprising a highly conductive plate having openings provided therein in the areas which underlie the chip carrier. The openings have inserts therein of a material which closely matches the thermal coefficient of expansion of the ceramic to thereby reduce stress of the intermediate solder joints.

Inventors

  • 👤 James F. Burgess

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 16:08
CPC Classifications
H; H05; H05K; H05K1/00; H05K1/02; H05K1/03; H05K1/05; H05K1/056; H05K1/0271; H05K1/0306; H05K1/0313; H05K1/0353; H05K1/036; H05K2201/00; H05K2201/01; H05K2201/0183; H05K2201/0187; H05K2201/06; H05K2201/068; H05K2201/10; H05K2201/10227; H05K2201/10416; H05K2201/10613; H05K2201/10621; H05K2201/10727; Y; Y10; Y10S; Y10S428/00; Y10S428/901; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49124; Y10T29/4913; Y10T29/49144; Y10T428/00; Y10T428/24; Y10T428/24802; Y10T428/24917; Y10T428/24926

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 97 words
An integrated circuit board assembly comprising: a leadless integrated circuit chip carrier; a plurality of conductive terminals associated with said carrier and extending along one face of said carrier; a printed circuit laminate including a plurality of contact strips, said strips electrically coupled to said terminals via electrical connections; and an inner core on which said laminate is supported, said core including a highly thermally conductive plate having openings therein, said openings located juxtaposed to said one face of said chip carrier and containing inserts having a thermal coefficient of expansion closely matching that of said carrier.
Claim 2
Dependent Claim 97 words
An integrated circuit board assembly comprising: a leadless integrated circuit chip carrier; a plurality of conductive terminals associated with said carrier and extending along one face of said carrier; a printed circuit laminate including a plurality of contact strips, said strips electrically coupled to said terminals via electrical connections; and an inner core on which said laminate is supported, said core including a highly thermally conductive plate having openings therein, said openings located juxtaposed to said one face of said chip carrier and containing inserts having a thermal coefficient of expansion closely matching that of said carrier.
Claim 3
Dependent Claim 19 words
The combination recited in claim 1 wherein said carrier is selected from the group comprising plastics, metals and ceramics.
Claim 4
Dependent Claim 21 words
The combination recited in claim 1 wherein the thickness of said laminate is small relative to the thickness of said core.
Claim 5
Dependent Claim 16 words
The combination recited in claim 1 wherein said laminate includes alternate layers of copper and polyimide.
Claim 6
Dependent Claim 13 words
The combination recited in claim 1 wherein said electrical connections comprise solder joints.
Claim 7
Dependent Claim 21 words
The combination recited in claim 1 wherein said carrier is made of a ceramic material and forms a hermetically sealed package.
Claim 8
Dependent Claim 112 words
A circuit board comprising: a highly conductive metal plate, said plate having a plurality of openings therein; a plurality of metal inserts mounted in said openings, the surfaces of said inserts being substantially flush with the surfaces of said plate to form a planar mounting surface; an insulating layer carried on said mounting surface; an integrated chip carrier mounted on said insulating layer, said layer having deposited thereon conductive strips electrically coupled to conductive portions of said chip carrier, said carrier being supported juxtaposed to one of said inserts, said inserts being made of a material having a coefficient of thermal expansion closely matching the coefficient of thermal expansion of said carrier.
Claim 9
Dependent Claim 112 words
A circuit board comprising: a highly conductive metal plate, said plate having a plurality of openings therein; a plurality of metal inserts mounted in said openings, the surfaces of said inserts being substantially flush with the surfaces of said plate to form a planar mounting surface; an insulating layer carried on said mounting surface; an integrated chip carrier mounted on said insulating layer, said layer having deposited thereon conductive strips electrically coupled to conductive portions of said chip carrier, said carrier being supported juxtaposed to one of said inserts, said inserts being made of a material having a coefficient of thermal expansion closely matching the coefficient of thermal expansion of said carrier.
Claim 10
Dependent Claim 11 words
The combination recited in claim 7 wherein said plate is copper.
Claim 11
Dependent Claim 12 words
The combination recited in claim 7 wherein said layer comprises a polyimide.
Claim 12
Dependent Claim 28 words
The combination recited in claim 8 wherein said carrier is made of a ceramic material and said inserts are made of an alloy of nickel, iron and cobalt.
Claim 13
Dependent Claim 29 words
The combination recited in claim 8 wherein said inserts are locked directly opposite the areas of contact between said conductive portions of said chip carrier and said conductive strips.
Claim 14
Dependent Claim 32 words
The combination recited in claim 1 wherein said carrier is made of a ceramic material, said inner core is made of copper, and said inserts are located directly opposite said electrical connections.

References Cited (Backward Citations)

US4385202A Cited
US4546406A Cited
US4318954A Cited
US4570337A Cited
US4581680A Cited
US4590095A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-12-07 1991-06-08 1991-12-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-12-07 1995-06-08 1995-12-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-12-07 1999-06-08 1999-12-08 $7700.00 Window Closed / Lapsed

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