Emerging trends in wide band gap semiconductors (SiC and GaN) technology for power devices

Among the wide band gap (WBG) semiconductors, silicon carbide (4H-SiC) and gallium nitride (GaN) are nowadays recognized as outstanding materials for the future of power electronics. In fact, owing to their excellent properties, they can guarantee a better energy efficiency in power conversion systems with respect to Silicon. Today, although several SiC and GaN devices have already reached the market, there are still many technological issues to be faced in order to fully exploit the enormous potential of these materials. In this context, this paper aims to review some emerging trends in the processing of WBG semiconductor devices (e.g., diodes, MOSFETs, HEMTs, …). The focus will be put on some selected “hot topics”, like the channel mobility in SiC MOSFETs, the Ohmic contacts to SiC devices, and the approaches for normally-off GaN HEMTs. Finally, a summary of the open issues and a short outlook on the future perspectives of SiC ultra-high-voltage devices and vertical GaN devices will be given.