Advanced silicon carbide gate turn-off thyristor for energy conversion and power grid applications

The need for power semiconductor devices capable of high-voltage, high-frequency, and high-temperature operation has been continuously growing, especially for energy conversion system and related power grid applications. However, current power converters built with silicon switches are quite bulky and inefficient, making their utilization difficult in practical energy conversion and power grid systems. The development of high-voltage power devices based on wide bandgap semiconductor such as silicon carbide (SiC) has attracted great attention due to its superior material properties over silicon. Among the high-voltage SiC power devices, SiC gate turn-off thyristor (GTO) offers excellent current handling, very high voltage blocking, and fast turn-off capabilities. SiC GTO also exhibits lower forward voltage drop than the IGBT-based switch, resulting in lower losses during normal operation. In this paper, we report our recently developed 1 × 1 cm2, 12 kV SiC p-type GTO with improved carrier lifetime.