Finite Element-Based Monitoring of Solder Degradation in Discrete SiC MOSFETs

Many of the reliability methods used in power electronics require extensive experimental data, resulting in long product design cycles. This work focuses on developing a simulation-driven approach to assess the reliability of a discrete silicon carbide MOSFET by monitoring $2^{\mathrm{n}\mathrm{d}}$ level solder degradation under power cycling in the thermal and thermo-mechanical domains. Active power cycling tests are performed to determine the loading condition at which end-of-life is reached due to a 20% increase in thermal resistance. Numerical analysis using finite element simulations is conducted to gain a physical understanding of the failure criterion from a mechanical point of view. The proposed methodology aims to accelerate the quality assurance and product qualification processes of discrete power electronic devices.