Optimization of Current Aperture Length for Enhanced RF Performance in GaN CAVET Devices

Abstract:
In this work, we present a radio frequency (RF) assessment to optimize the Gallium Nitride (GaN) current aperture vertical electron transistor (CAVET). Lateral scaling of the length of the current blocking layer (CBL) exhibits the influence of current aperture length on RF characteristics, including gate capacitances (Cgs and Cgd), transconductance (gm), cut-off frequency (fT), and maximum oscillation frequency (fMAX). The optimization of the aperture length of GaN CAVET reduces the intrinsic gate capacitances and paves the way for high-performance RF applications. The optimized device shows an improvement of 69% and 89% in the case of fT and fMAX values and an 87% increase in the √(fT×fMAX) value. The maximum unilateral power gain of 32 dB is achieved for GaN CAVET with a large aperture length. The optimization of the current aperture length in GaN CAVET promises breakthrough performance for widespread RF applications.