Reduction of off-state drain current in AlN/β-Ga₂O₃ HEMT by trap state engineering

Abstract

In this work, we report various strategies to reduce the off-state drain leakage current () in AlN/ high electron mobility transistor (HEMT) by 2D device simulation. We have investigated the effect of access region, channel doping concentration, barrier layer thickness, and trap state engineering on . The formation of a parallel channel deep into the substrate has been found to be responsible for large . All other strategies except trap state engineering have an incremental effect on . However, the device’s was reduced by around 12 orders of magnitude by trap-state engineering. Simultaneously, the on-state performance was unaffected, resulting in an elevated / current ratio of (). A steep subthreshold slope of 0.267 (V/dec) was also obtained. Further, we have investigated the impact of both donor- and acceptor-type traps on subthreshold characteristics. These promising results highlight the potential of AlN/ HEMT as a switch and for future high-power nanoelectronics applications.