High power multichip modules employing the planar embedding technique and microchannel water heat sinks

This paper describes a novel packaging technology for high power multichip modules (MCMs). The work covers three areas: The fabrication of a multichip module which provides access to the die backside for heat removal, the development of high performance microchannel heat sinks with a matched CTE, as well as a low thermal resistivity assembling technology. The MCM is fabricated by means of the planar embedding technology. By planarizing the module backside a low thermal resistance between heat sink and dice can be accomplished simultaneously for all embedded components. A thermotest module of size 2/spl times/2 capable of a power dissipation of several hundred watts was fabricated. Thermal resistance values below 0.6 Kcm/sup 2//W at 50 W/cm/sup 2/ chip flux have been achieved.