Transport simulation of bulk AlxGa1−xN and the two-dimensional electron gas at the AlxGa1−xN/GaN interface

Abstract

In this work, a hybrid Monte Carlo simulation with the inclusion of degenerate statistics has been performed to analyze electron transport in bulk AlxGa1−xN, and the two-dimensional electron gas at the AlxGa1−xN/GaN interface. The results of the steady-state drift velocity, average electron energy, and distribution functions for bulk AlxGa1−xN are presented. A study of the change in transport properties with compositional variations has been made and presented here. Degeneracy has been found to affect electron transport in both the low- and the high-field regions. The inclusion of degeneracy caused a pronounced negative differential mobility. Simulation of the two-dimensional electron gas takes into account three subbands at the AlxGa1−xN/GaN interface. A self-consistent solution of the Schrödinger and Poisson equations at the heterointerface is obtained through a Rayleigh–Ritz method that should result in more accurate electron wave functions, and hence, more accurate scattering rates for the two-dimensional electron gas. The inclusion of degenerate statistics caused an increase in the interband occupancy in addition to an increase in the electron kinetic energy in the subbands.