Study on Self-Parallel GaN-Based Terahertz Hetero-Structural Gunn Diode

Abstract

In this paper, we propose a novel gallium nitride-based multi-two-dimensional-electron-gas (2DEG)-channel self-parallel Gunn diode (SPD) for the first time. In the SPD, a trench anode is etched through at least the bottommost 2DEG channels, which splits all 2DEG channels into two shorter channels with lengths of L1 and L2. Therefore, one SPD is just equal to several shorter diodes in parallel; as a result, we call it a self-parallel Gunn diode. In the symmetrical SPD, the component of fundamental frequency is nearly multiplied as compared with the regular Gunn diode. In the asymmetrical SPD (L2 = nL1, n is a positive integer), the harmonic components are greatly enhanced, specially the nth harmonic. Our work demonstrates that the GaN-based terahertz SPD not only offers an easy transfer between two different frequencies, but also realizes the simultaneous enhancement of oscillation power and frequency.