Theoretical and Experimental Analysis of Microchannels Heat Sink Obtained by Silicon Micromachining

Abstract The use of microchannels in silicon substrates as a forced liquid cooling device for power integrated circuits is investigated. The new concept presented in this work consists in placing water cooled heat sink structure directly inside the silicon substrate. This configuration allows the refrigerant liquid to be as close as possible to the heat generation source (circuit) which increases its efficiency. On the other hand, the integration of the microchannels inside silicon substrate reduces the umber of heterojunctions involved in the cooling device which has a bent impact on the thermal stress. Thanks to the use of two commercially available softwares Flux3D and Pascosma, thermal dissipation characteristics of several prototypes were simulated. On the base of some simplifying hypothesis clearly stated, a theoretical optimization of these prototypes were carried out allowing to find ma the optimum dimensions of a cooling device operating under a given set of experimental constraints. Finall3 a first prototype realization within a fully compatible silicon integrated circuits technology is described and its preliminary experimental characteristics are presented.