The effect of collisional broadening on Monte Carlo simulations of high-field transport in semiconductor devices

Some important consequences of the uncertainty principle on Monte Carlo simulations of very high field transport are discussed. It is shown that recent values of the phonon scattering rates reported for GaAs by Shichijo and Hess lead to an unrealistically high collisional broadening (0.3-0.6eV) of the electronic states, thus rendering questionable any attempt to relate transport properties to the band structure, and invalidating the semiclassical Boltzmann transport picture used in the Monte Carlo simulation. These considerations are important in the modeling of very high field transport properties in semiconductor devices.