Transient Thermal 2D FEM Analysis of SiC Mosfet in Short-Circuit Operation Including Solidus-Liquidus Phase Transition of the Aluminum Source Electrode

Understanding electrothermal SiC power Mosfet behavior in extremely abnormal operations such as short-circuit is a major need for certification, especially for critical or long-life applications. But simulating short-circuits in electronic components is very difficult because we need a fully electric and thermal Multiphysics model. We also need to model the top aluminum electrode melting. We have used the “apparent heat capacity” method to model this melting, which considers the latent heat and the needed absorbed energy during the fusion. So, for the first time, this article presents a numerical finite element model that fully simulates in 2D the dynamic electrothermal behavior of a SiC power transistor in short-circuit regime. The geometric precision of this model provides significant added values compared to existing 1D models.