Implementing variable doping and work function engineering in β-Ga2O3 MOSFET to realize high breakdown voltage and PfoM

Abstract

In this paper, the impact of workfunction engineering and lightly doped region near drain has been studied on lateral β-Ga2O3 metal oxide semiconductor field effect transistor (MOSFET) by employing exhaustive technology computer aided design simulations. The theoretically predicted value of breakdown voltage and power figure of merit (PFoM) for Ga2O3 based devices has not been achieved yet, and hence in order to improve these parameters, variable channel doping and work function engineering have been implemented on lateral β-Ga2O3 MOSFET for the first time in the present work. A thorough comparative assessment has been drawn by comparing the characteristics of the proposed device which incorporates work function engineering along with a variable doping in channel such that higher doping is near the source side and a lower doping region is near the drain end with conventional, doping engineered and work function engineered β-Ga2O3 devices and it is demonstrated that the proposed device offers significant improvement in breakdown voltage and PFoM. Furthermore, the performance of all devices under consideration has been evaluated at high temperatures as well and it is demonstrated that the proposed device offers superior performance in comparison to other devices, and hence is a suitable contender for high voltage and high temperature applications.