Electro-Thermal Simulation of Power DMOS Devices Operating under Fast Thermal Cycling

An electro-thermal simulation setup using a FEM-based simulator is being calibrated for adequate modelling of the thermal behavior of a DMOS power transistor operating under fast thermal cycling. The computational domain is defined by selecting the essential geometry details of the chip. A method of homogenization is used to reduce the complexity of the chip metallization. Equivalent anisotropic thermal properties and their temperature dependencies are extracted for the homogenized regions. The simulation stimuli are adjusted so that they replicate the testing conditions. Transient electro-thermal simulations are performed and their accuracy is assessed by comparison with the experimental data. A second comparison is performed between a highly detailed model and the homogenized one in order to assess the reduction in simulation time and possible accuracy loss.