Numerical simulation and parametric assessment of GaN buffered trench gate MOSFET for low power applications

Abstract

This study presents numerical simulation of a novel gallium nitride buffered trench gate (GaN-BTG) metal oxide semiconductor field effect transistor (MOSFET) for high-speed and low-power applications. The electrical characteristics of GaN-BTG-MOSFET are compared with BTG MOSFET and conventional trench gate MOSFET. A comparative study of different performance factors such as electric field, electron velocity, threshold voltage (Vth), electron mobility, and sub-threshold swing (SS) of these devices has been performed. Results reveal a 43.85% improvement in SS and 9.83% decrement in Vth for GaN-BTG-MOSFET. Furthermore, the frequency analysis has been performed in terms of scattering (S) parameters, cut-off frequency (fT) and maximum oscillator frequency (fMAX) to show how the device is also suitable for radio frequency applications. Furthermore, the study of parametric variation of GaN-BTG-MOSFET with the change in channel length, oxide thickness (tox), and doping concentration has also been presented. Results show that GaN-BTG-MOSFET can act as a promising structure for further scaling down of the trenched MOSFET and assures better performance for sub-20 nm trenched MOSFET.