【International Papers】Enhancement mode β-(Al₀.₁₉Ga₀.₈₁)₂O₃/Ga₂O₃ HFETs with superlattice back-barrier layer

      Researchers from the Hongik University have published a dissertation titled "Enhancement mode β-(Al_0.19Ga_0.81)₂O₃/Ga₂O₃ HFETs with superlattice back-barrier layer " in Micro and Nanostructures.

Abstract

      In this study, we numerically investigate the improvement in maximum drain current of an enhancement-mode β-(Al_0.19Ga_0.81)₂O₃/Ga₂O₃ heterostructure field-effect transistor (HFET) that employs a superlattice back-barrier layer. The measured transfer characteristics of a recently reported enhancement-mode β-(Al_0.19Ga_0.81)₂O₃/Ga₂O₃ HFET are reproduced using a device simulation and modeling tool. Subsequently, the transfer, output, radio frequency (RF), and off-state breakdown characteristics of the proposed device are revealed. The calculated off-state breakdown voltage is drastically enhanced from 26 V to 93 V for a gate length (L_G) of 195 nm and a gate-to-drain separation (L_GD) of 190 nm because of the superlattice back-barrier, which is one of the highest breakdown voltages reported for submicron Beta-Gallium Oxide (β-Ga₂O₃) transistors. Moreover, the insertion of the superlattice back-barrier layer improves subthreshold characteristics, resulting in a positive shift in the threshold voltage. The results indicate that using the superlattice back-barrier can dramatically enhance both the off-state current characteristics and RF characteristics of the enhancement mode in highly scaled β-Ga₂O₃ HFETs.

Original link:https://doi.org/10.1016/j.micrna.2024.207802