The increase in operating temperature is one of the current trends in power electronics. This operation leads firstly to changes in the structure of power modules such as "3D" structures to provide a double-side cooling of power components, and secondly the use of materials that reduce thermomechanical stresses, related to the difference in coefficient of thermal expansion. The study realized during this thesis consisted in developing a new "3D" structure based on copper microposts prepared by electroplating, which are then assembled to a metallized ceramic substrate (eg, a DBC: Direct Bonding Copper). To realize this contact, a sintering machine (SPS: Spark Plasma Sintering) is used first to study the direct bonding of copper on solid, and second to perform the bonding between the copper microposts and the DBC. This technique is also used for the production of a new metallized ceramic substrate using materials with matching thermal expansion coefficients, for high temperature applications.
