6.5 kV Si/SiC Hybrid Power Module Technology

Abstract

Substituting Si diodes with SiC Schottky diodes in Si insulated gate bipolar transistor (IGBT) modules is beneficial, as it can reduce power losses in electrical systems significantly. The fast switching nature of the SiC diode will allow Si IGBTs to operate at their full high-switching-speed potential, which at present is not possible because of the Si diodes. In this work, the electrical test results for Si-IGBT/4HSiC-Schottky hybrid substrates (hybrid SiC substrates) are presented. Comparisons of the 6.5 kV Si and hybrid SiC at room temperature and high temperature have shown that the switching losses in hybrid SiC substrates are low as compared to those in Si substrates but necessary steps are required to mitigate the ringing observed in the output waveforms.