Physics of GaN-based heterostructure field effect transistors

GaN-based field effect transistors might replace other compound semiconductor FETs in microwave and, possibly, even in millimeter and submillimeter wave applications. New device physics of these devices (primarily linked to their wurtzite symmetry and to small nitrogen mass) has to be understood to facilitate this process. In this paper, we review the new physics of polarization, electron transport, and gate leakage, and current collapse in these devices.