ANSYS based 3D electro-thermal simulations for the evaluation of power MOSFETs robustness

Electro-thermal simulators are useful tools for introducing design and technology improvements during the design process of power MOSFET transistors. They are also helpful to predict the device behavior when operating under extreme electrical and temperature conditions and thus to predict its thermal robustness. Such simulators have to correctly take into account interactions between electrical and thermal behavior. In this paper we propose a new method to perform electro-thermal simulations of power MOSFETs using ANSYS simulator. The electrical and the thermal problem are fully coupled and iteratively solved using the FEM method. By means of a test chip, simulations and comparison with measurement have been performed in order to validate the simulation approach.