Crystal defects in wide bandgap semiconductors

The state-of-the-art power switching devices made from SiC and GaN semiconductors contain a high density of crystal defects. Most of these defects are present in starting wafers and some are generated during device processing. There is little conclusive evidence so far on the exact role that the crystal defects paly on device performance, manufacturing yield, and more importantly, long-term field-reliability especially when devices are operating under extreme stressful environments. This paper provides a review of the current state-of-the-art of SiC and GaN power semiconductor material technology, and the potential impact crystal defects may have on high-density power switching electronics. A review of silicon technology development and manufacturing evolution is made to draw a parallel between silicon and wide bandgap (WBG) semiconductor power electronics.