Implementation of source extended multiple field plates and asymmetric doping on β-Ga2O3 MOSFET for high power applications

Abstract

In the present work, source extended multiple field plate design is implemented on β – Ga2O3 MOSFET and asymmetric doping design has been adopted in the channel such that higher doping is present at the source side and lower doping is considered at the drain side to achieve superior performance for power applications. Extensive numerical simulations using TCAD Silvaco have been conducted and the optimization of various critical parameters of the proposed device, including the number and lengths of field plates and channel doping, has been undertaken to achieve superior power performance. Further, a comparison is drawn between the proposed device with (i) the device with multiple field plates at the source side and uniform channel doping, and (ii) the conventional device (without field plates and asymmetric channel doping) in terms of various critical attributes such as ON-state resistance, drain current, transconductance, breakdown voltage and power figure of merit etc. The present study demonstrates that the proposed device yields not only a remarkable improvement of 261 % in breakdown voltage and a substantial improvement in PFoM of 1120 % but also delivers higher drain current and peak transconductance when compared to the other devices under consideration. Additionally, the performance of all devices has been investigated at elevated temperatures and it has been found that the proposed device is well-suited for high-temperature applications as well since least degradation in drain current at higher temperatures is observed for the proposed device.