Westinghouse Electric Corporation

John A Olenick

David B Harris

Robert A Bourdelaise

Denise B Harris

Allen B Timberlake

Both a co-fired ceramic package for a power circuit is disclosed as well as a method of manufacture thereof. The package includes a base which is formed from a plurality of pyrolizable ceramic films, each of which includes a heat-conductive and electrically insulative ceramic material such as aluminum nitride, silicon carbide or beryllium oxide embedded within a binder. In the method of the invention, two or three ceramic films are metalized with a pattern of conductive material on their top surfaces. The resulting metalized films are then stacked over a plurality of unmetalized ceramic films, and the resulting aggregate stack is laminated together by the application of heat and pressure. Electrical components are then soldered onto the top surface of the base, and a cover is sealingly connected around the resulting hybrid circuit. The metalization step advantageously forms terminals around the cover which allow access to the heat generating power circuit without the need for glass post seals. The resulting, integrated ceramic structure is free of internal thermal stresses, and affords better heat dissipation characteristics than prior art devices.

Co-fired ceramic package for a power circuit

The invention is an improved chip carrier assembly utilizing a cavity-down chip carrier with a pad grid array wherein the IC chip within the chip carrier is mounted against a surface opposite the PWB to which the chip carrier is attached such that heat transfer from the IC chip may occur along a short path to a heat sink such that a large heat transfer rate is possible. Furthermore, the apparatus utilizes an alignment and electrical connection means between the contact pads of the chip carrier and a PWB to which the chip carrier is attached to compensate for shrinkage variation which occurs during the chip carrier fabrication process. Furthermore, within the cavity of the chip carrier there is space for additional components such as a decoupling capacitors. This permits the design of an apparatus providing better heat transfer properties, more accurate contact pad locations and the option of including within the chip carrier components which in the past had been mounted outside of the chip carrier.

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Columbia, MD, United States of America

John A Olenick