Electrical Characterization of Modular 3D Packaging Assembled With Removable Metal Parts

This paper proposes a novel modular packaging concept based on the 3D integration of 1.2 kV SiC MOSFET with metal foams for electrical contacts with pressure assembly. The latter make possible the disassembly of switching cells by keeping low electrical resistance and inductance inside the package. Thus, static and dynamic experimental characterizations are carried out to evaluate their impact compared to copper interposers. Static measurements show that the electrical resistance of the package is in the range from 3 to 4 mΩ. Dynamic characterizations demonstrate that the stray inductance of the switching cell is close to 3 nH. With results obtained with copper interposers close to the ones obtained with foams, the material used for the electrical interconnection have low impact on the electrical performances of the power module. However, the modification of the pressure distribution in the power module induces a modification of the resistance and stray inductance. This dependency is more important for copper interposers because they are non-deformable.