Design and Demonstration of High Breakdown Voltage GaN High Electron Mobility Transistor (HEMT) Using Field Plate Structure for Power Electronics Applications

AlGaN/GaN power high electron mobility transistors (HEMTs) with a breakdown voltage of 600 V are fabricated and demonstrated as switching power devices for motor drive and power supply applications. A high breakdown voltage was realized in the fabricated power-HEMT by the field plate technique and an ultra low on-state resistance of 3.3 mΩ·cm2, which is 20 times lower than the silicon limit, due to the high critical field of the GaN material and the high mobility in a two-dimensional electron gas channel. A device with the double-field plate structure was also designed using two-dimensional device simulation to increase the breakdown voltage without any increase of the GaN layer thickness.