Towards terahertz optopair based on AlGaN/GaN HEMTs

Abstract

We present investigations of the fin-shaped GaN/AlGaN field effect transistors with two lateral Schottky barrier gates exactly placed on the edges of the fin-shaped transistor channel. We call this kind of FinFET modification the EdgeFET. It allowed us to efficiently control the current flow in two-dimensional electron gas conduction channel. We present experimental data of sub-THz detection by EdgeFETs. Control of the side gates allows changing the width of two-dimensional electron gas and forming a wire, as we expect should be beneficial for observation of terahertz plasma wave resonances. This paves the way towards future terahertz optopair using high-quality factor plasma wave resonances, for which it is necessary to eliminate oblique modes. We report also on the high-voltage, noise, and radio frequency (RF) performances of aluminium gallium nitride/gallium nitride (AlGaN/GaN) on silicon carbide (SiC) devices without any GaN buffer. Such a GaN–SiC hybrid material was developed in order to improve thermal management and to reduce trapping effects should be beneficial for observation of resonant emission.