Long-term Reliability of Discrete 1200 V SiC Trench MOSFETs at 200degC Junction Temperature

Abstract:
Higher power density is a key factor in reducing system costs. Due to their fast switching capabilities, silicon carbide (SiC) trench MOSFETs increase the power density in applications with high switching frequencies. Higher switching frequencies can increase thermal stress, which negatively impacts the device’s lifetime. To enable the temperature withstanding capability of SiC MOSFETs fully, the packaging has to be adapted accordingly. Discrete packages currently available in the market usually use the standard soldering techniques for attaching the die. We investigated packages with diffusion soldering through reliability tests to demonstrate the high robustness of this assembly method. Results showed that a 1200 V SiC MOSFET combined with an advanced package can withstand a junction temperature of 200deg C.