Patent ID: 7285851

Claim:
A liquid immersion cooled multichip module comprising: a) a printed circuit board; b) a substrate having a plurality of chips mounted thereon and being adapted to mount with the printed circuit board; c) a lid adapted to be secured to the printed circuit board so as to mount with the substrate to form a fluid chamber between the lid and the substrate, and to cause the substrate to mate with the printed circuit board; d) a bolster plate on a side of the printed circuit board opposite the lid, the lid being fastened to the bolster plate to secure the lid to the printed circuit board; and e) a baffle within the lid constructed to direct a flow of coolant through the fluid chamber, the baffle being constructed to direct a flow of coolant through the lid along a generally U-shaped flow path having an inbound segment leading to a transition segment followed by an outbound segment, the outbound segment supplying coolant fluid over the plurality of chips so as to provide a parallel flow over a first set of chips followed by a series flow over a downstream chip, the inbound segment supplying a partial flow of coolant laterally across an adjacent chip of the first set of chips so as to combine with the parallel flow.