2 dimensional electron gas uniformity of GaN HFET layers on SiC

As GaN power transistor technology matures it is increasingly important to understand any links between substrate “quality”, epi-layer growth and electrical characteristics of the 2-dimensional electron gas (2DEG), which forms the active part of devices. We present a study, which makes use of full wafer mapping techniques to examine these relationships. Substrate off-cut is shown to be an important parameter in controlling the uniformity of GaN HFET device layers on SiC substrates.