MONTE-CARLO SIMULATION OF HIGH-FIELD ELECTRON-TRANSPORT IN GAAS USINGAN ANALYTICAL BAND-STRUCTURE MODEL

We present a study of high energy electron transport in GaAs using an analytical model of the band structure. This model is based on piecewi se polynomial approximation of the dispersion relation in different re gions of the Brillouin zone. It accounts for the first two conduction bands and reproduces all important features of the full band structure . We have used this model to set up a Monte Carlo simulation of electr on transport accounting for impact ionization. It has been shown that this ''extended valley'' model yields essentially the same results as the most rigorous full band Monte Carlo calculations. We have found a large influence of high energy anisotropy on electron transport. Anoth er important result is that most impact ionization events are due to e lectrons in the second conduction band. (C) 1997 American Institute of Physics.