Application of Finite Element Simulations for the Determination of Defects in Electrical Interconnections in Power Modules

In this study, finite element simulations are used as a tool to predict the change in the magnetic field distribution of a power module, when a current is applied and wire bond lift-off is taking place. For this purpose, an accurate 3D model of the module is generated with an AutoCAD program. Also models are generated containing wire bond defects in different locations. A magneto static simulation of the B-field distribution is then performed using Ansys Maxwell. In parallel, actual measurements on a real module are conducted in the laboratory. A comparison of the simulation and the measurement results show that simulations have a high accuracy in predicting real behavior during failure.