Monte Carlo simulation of impact ionization and current multiplication in short GaAs diodes

Abstract

We have modelled carrier transport and impact ionization in bulk GaAs and GaAs diodes using two Monte Carlo models, one using analytical band structure, the other employing more realistic pseudopotential band structure. Despite the relative lack of sophistication of the analytical model and the poor representation of band structure at higher energies, the analytical model reproduced accurate drift velocities, mean energies and impact ionization rates in good agreement with experiment and the more sophisticated model. Both models accurately simulated the diodes, agreeing well with experimental results and the two models also agreed with each other with respect to the microscopic aspects of the carrier transport in these devices.