Monte Carlo study of low and high-field electron transport in GaN-based heterostructures

Electron transport properties of GaN-based heterostructures are investigated by means of a Monte Carlo model, which considers a large number of subbands in several valleys. Room-temperature low-field mobility consistent with experimental results is obtained provided that screening of phonon scattering is accounted for. In intrinsic heterostructures the mobility is always greater than in bulk GaN. Dislocations strongly reduce mobility at low electron density. Transport under applied field up to 300 kV/cm is also investigated. The peak velocity is found to decrease when electron density is increased.