High transconductance AlGaN/GaN optoelectronic heterostructurefield effect transistor

Abstract

The authors report on 1 µm gate Al0.15Ga0.85N/GaN heterostructure field effect transistors, which demonstrate a high transconductance (up to 64 mS/mm) under illumination. The increase in the transconductance and in device current under light is explained by the creation of trapped positive charge and conduction electrons in the channel, which enhances the surface density of the two-dimensional electron gas in the device channel up to 2 × 1012 cm-3 and decreases the source series resistance.