Modeling and Optimization of Linearity in AlGaN/GaN Tri-Gate Fin-HEMTs Using Fin Configurations and Modulated Barrier Doping for Higher fT and fmax Using Small-Signal Analysis for RF Power Electronics Applications

In this study, we explore the modeling and optimization of trigate fin HEMT structure by varying the dimensions of fin height (Hfin) and fin length (Lfin) to enhance linearity by systematically adjusting the fin dimensions using SILVACO ATLAS, we aim to identify the optimal configurations that yield a flat transconductance. A mathematical model is developed which is governed by fin dimensions and tracks the transconductance. With a proposed linearity ratio which leads to a flat transconductance gain characteristic enabling these devices to be effectively used in RF power electronics systems. Also modulated doped AlGaN barrier aimed at enhancing transconductance without degrading linearity was done in this paper. Scattering parameters were extracted across a frequency range of 1 to 20 GHz, providing critical insights into the high-frequency behavior of the device and stability of a device which is understood by Maximum available gain (MAG) and maximum stable gain (MSG). The small-signal analysis using MATLAB revealed significant improvements in both the cutoff frequency (fT) and the maximum oscillation frequency (fmax) with wide range of gate to source voltage bias critical for RF power electronics amplifiers.