A MANY-BAND SILICON MODEL FOR HOT-ELECTRON TRANSPORT AT HIGH-ENERGIES

A new silicon model for electron transport at high electric fields is presented. The model features an original conduction-band structure consisting of three isotropic bands together with the lowest non-parabolic band in a finite spherical Brillouin zone. The bands are given by analytic expressions whose parameters are fixed by best fitting the density of states taken from band-structure calculations. Such a model is consistently used in electron dynamics and in the evaluation of the scattering probabilities. The coupling constants to the scattering agents are determined by best fitting the available experimental data on transport properties. The effect of the new model on the results is discussed for a bulk system with particular attention to the features (e.g. the detailed shape of the electron distribution function) which are important for device applications.