Abstract EN:

With the scaling down trends and the increasing of frequency operation, the electronic power converters are subjected to an unsteadily increasing dissipated power. In order to avoid an excessive temperature increase at the chip's level, it becomes fundamental ta supply each electronic power device with an appropriate efficient cooling device. Hybrid micro-heat sinks elaborated in copper technology have been widely investigatedsince the last decade. Nevertheless, because of their multilayer structure, these devices are usually characterised by. An important thermal fatigue and brittle copper fines. An alternative solution is reported to be the use of silicon microtechnologies to fabricate the microchannels heat sink directly in the electronic chips material (i. E. Silicon substrate). This thesis was focusing on the design and realisation of micro heat sink in silicon -technology. The first chapter is an overview of the thermal and hydraulic principles which govern the forced convection heat exchange between water and silicon microchannel's walls. The second chapter deals with the major technological innovative steps which were used for the fabrication of the first prototYPes. A third chapter is dedicated to the numerical simulation tools and to' the experimentalcharacterisation bench. A comparison between experimental results and simulation predictions is thotougbly discussed in order to find out the validity limit of certain hypothesis. Finally, an optimisation procedure aiming to determine the optimal micro heat sink configuration is proposed