An improved ionized-impurity scattering model for Monte Carlo simulations

An improved Monte Carlo model for ionized-impurity scattering is developed and used to calculate majority- and minority-electron mobilities in silicon. The model includes scattering cross sections derived from phase-shift analysis, implementation of the Friedel sum rule, and a simple phenomenological model for multiple-potential scattering. This model provides a very good fit to experiment using a single adjustable parameter. Electron mobilities in n- and p-type Si are calculated and fit to experimental data at 300 and 77 K. Experimental results for Si of μn(NA)/μn(ND) ≊ 2 at 300 K are reproduced and a value of 3 < μn(NA)/μn(ND) < 4 is predicted at 77 K.