Mobility in n-(Al, Ga)As/GaAs heterojunctions at moderate electric fields

Hot-electron mobilities in (Al, Ga)As/GaAs single hetero-structures at 77 and 300 K are calculated for fields below 500 V/cm. Polar optic and acoustic deformation potential phonon scattering are considered, and intra- and inter-sub-band transitions in the first two sub-bands are included. The strong electron-electron interaction is assumed to enforce a displaced Maxwellian distribution function. The calculated results mostly explain the recently observed field variation of mobility.