Modelling Warpage Behavior of Molded Power Modules for Electric Vehicles

Epoxy molding compounds play an increasingly important role in the packaging of automotive power modules, as they allow for size reduction of the modules and provide good insulation and protection properties. However, these hard-encapsulation materials strongly influence the thermo-mechanical properties of the power modules. In view of processability and reliability, especially the warpage is crucial. In this study, the (visco-)elastic properties of two different epoxy molding compound materials are characterized and implemented into finite element simulations. A Design of Experiment setup yields valuable results of the influence of different geometrical factors on the warpage. It is shown that especially the thicknesses of the substrate and the molding compound strongly influence the deformation behavior at low and high temperatures.