An AlN/GaN insulated gate heterostructure field effect transistor with regrown n+GaN source and drain contact

Abstract

A nobel insulated gate heterostructure field effect transistor (IG-HFET) was demonstrated. The layer structure under the gate consisted of a thick AlGaN barrier, an n+GaN channel 15nm thick, and an AlN insulator 4nm thick, grown sequentially by MOCVD. The device operated with gate voltage up to +3V. The pinch-off voltage was about 0V, which resulted from the very high Schottky barrier height and the very thin AlN layer. The measured transconductance gm was 235mS/mm for Lg=1.4μm, which is the highest so far reported.