Switching characteristics of high-breakdown voltage AlGaN/GaN HEMTs

Abstract

In this report we present the switching measurements on large area AlGaN/GaN HEMT devices with high breakdown voltage achieved with the help of multiple field plates. AlGaN/GaN high electron mobility transistors have shown potential advantages over Si and SiC based transistors for high power switching. The very high electron mobility in the AlGaN/GaN HEMT system combined with the high density of polarization induced 2D electron concentration yield a very low on-resistance and high switching frequency. Also the high band gap energy of AlGaN/GaN system results in a high critical electric field. Hence it is possible to have high voltage power switches capable of operating at high frequencies (~100MHz). However there are some difficulties, which have prevented the achievement of very high breakdown voltages at high frequency operation