3.3 kV All SiC MOSFET Module with Schottky Barrier Diode Embedded SiC MOSFET

Abstract:
A 3.3-kV class third-generation silicon carbide (SiC) metal-oxide-semiconductor field-effect transistor (MOSFET) with an optimized cell structure consisting of a Schottky barrier diode (SBD) embedded in a SiC MOSFET is developed. The developed SiC MOSFET not only suppresses bipolar operation but also achieves 19% lower on-resistance compared with conventional SiC MOSFETs. We also develop a lowinductance package named iXPLV, whose stray inductance is reduced by 40% compared with conventional modules. We measure the switching losses of the developed MOSFET assembled in iXPLV and compare it with the switching loss of a silicon (Si) insulated gate bipolar transistor (IGBT) assembled in a conventional module. The switching loss of the developed module is 60% lower than the conventional Si IGBT with Si PiN diode and 43% lower than the Si IGBT with SiC SBD. We also estimate the effect of these loss reductions on the cooling unit volume, and the developed module is found to achieve a heatsink volume reduction of 40% compared with the module with a Si IGBT with Si PiN diode and 59% compared with the module with a Si IGBT with SiC SBD.