MODELING OF THE ELECTRONIC-STRUCTURE FOR AN ALGAAS GAAS/ALGAAS HFET WITH A DELTA-DOPING LAYER INSIDE THE QUANTUM-WELL/

The effect of a delta-doping layer inside the quantum well of an AlGaA s/GaAs/AlGaAs HFET is studied by a self-consistent modelling of the ba nd structure across the device in dependence on the geometric dimensio ns, the delta-doping density, and the gate voltage. The energy positio n of the delta-like donors inside the quantum well is attached to the lowest subband energy. Especially the results show the possibility to increase the channel charge and to control its spatial distribution wh ich could make possible an increase of the mobility of the device. It is shown that the potential obtained by a Modified Thomas-Fermi Approx imation is very suitable as a starting potential for the self-consiste nt calculation or even as a final result in special cases.