THERMAL PERFORMANCE OF A PASSIVE IMMERSION-COOLING MULTICHIP-MODULE

A Passive Immersion-Cooling Multichip Module (PIMM) for the direct liq uid cooling of microelectronic components with dielectric liquids was configured to meet expected Workstation thermal management needs. A la boratory module, internally-filled with fluorinert and containing 9 si mulated-chip heaters, was tested for different orientations, fin lengt hs, and cold-plate temperatures as well as for the effect of dissolved noncondensables. The 80 x 80 x 27 mm module had a ''submerged condens er'' finned with an array of square pin fins and was found to have a p eak heat dissipation capacity of 290 W with a cold-plate temperature o f 20 degrees C. The thermofluid phenomena encountered in the operation of the PIMM and the best available relations for the heat transport f rom the chips to liquid and from liquid to ''submerged condenser'' sur face are presented.