Enhancing AlGaN/GaN HEMT Performance through Gate-All-Around AlN Passivation: A Comparative Study with a Planar MIS-HEMT

This article offers a unique method for improving the performance of AlGaN/GaN high-electron-mobility transistors (HEMTs) by combining an AlN interfacial passivation layer with a gate-all-around (GAA) structure, known as a GAA-MIS-HEMT. The carrier concentration, electric field dispersion, and current density of the AlGaN/GaN interface are all strategically improved by the GAA approach. To achieve higher device performance, the two-dimensional electron gas is controlled with greater precision. The results of the GAA-MIS-HEMT configuration are carefully compared to those of the traditional planar-MIS-HEMT in this study, which uses an \(\textrm{Al}_{2}\textrm{O}_{3}\) ${\text{Al}}_2{\text{O}}_3$ dielectric. The findings unequivocally establish the superiority of the GAA-MIS-HEMT, showing significant gains in ON-state current, OFF-state current, transconductance, cutoff frequency (11 GHz), ON-state to OFF-state current ratio ( \(10^{11}\) ${10}^{11}$ ), ON-state resistance (0.9 \(\Omega \) $\mathrm{\Omega }$ − \(\textrm{cm}^{2}\) ${\text{cm}}^2$ ), and subthreshold slope (63 mV/dec). Notably, the constituent layers of the proposed structure are all intended to be doping-free. This study illustrates the potential of the GAA-MIS-HEMT design with AlN passivation for advanced electronic applications, opening up intriguing paths for improving AlGaN/GaN HEMT performance.