Short-circuit safe operating area of superjunction MOSFETs

Superjunction (SJ) Si-MOSFET power transistors have a larger active volume and thus a higher heat capacitance than wide-bandgap semiconductors with the same voltage and current rating. This could allow for higher power dissipation levels and thus increased short-circuit robustness. Therefore, this paper investigates the safe operating area (SOA) of a state-of-the-art SJ-MOSFET in short-circuit operation with high drain-source voltages by both measurements and simulations. The observed behavior will be discussed and explained using a simple physics-based simulation model, taking both the electrical and the thermal behavior of the device into account. The obtained results are useful to assess the applicability of SJ-MOSFETs for emerging application. Moreover, they can also serve as a valuable starting point for further device improvements.