Control of band discontinuity at III-V semiconductor interface by Si intralayers

Control of valence band discontinuity at AlAs/GaAs interface by Si intralayers is studied using reformulated tight binding method. The hybrid energies are calculated in the sp(3)s* configuration. The valence band offset at the interface without intralayer is 0.46 eV, in good agreement with experiments. The tuning of valence band offset using intralayers yields a maximum at 0.5 ML with a value of 1.01 eV, corresponding to induced potential of 0.55 eV. The induced potential increases, reaches maximum and decreases between 0 and 2 ML. The physical significance is charging and discharging of the microscopic capacitor, having a corresponding maximum induced potential at the saturation doping. (C) 2003 Published by Elsevier B.V.