A correlation between thermo-mechanical finite elements tool with electro-thermal finite elements tool: towards an electro-mechanical finite elements modeling for IGBT used in power assemblies

Our objective is to establish a connection between finite elements mechanical simulations using ANSYS software applied on a power module including a silicone die with finite elements electrical simulations using TCAD SENTAURUS software applied on a silicone power transistor, such as a Planar Gate Punch Through Insulated Gate Bipolar Transistor (IGBT). In this paper, the thermo-mechanical finite elements software is used to obtained the mechanical stress distribution within the silicone die under the four points bending configuration. Then, the mechanical stress is implemented in the semiconductor device simulator to obtain three static configurations (output characteristics, forward transfer and breakdown voltage). Simulation results show the same tendency as experiments and illustrate that whereas the mechanical stress has low effect on breakdown voltage, the forward current as well as the transconductance are strongly affected by external mechanical stress depending on its level, direction and nature (compressive or tensile).