A systematic investigation of the effect of the material and the structural parameters on the hole states in strained p–Si/Si1 − xGex/p–Si selectively doped double heterojunctions structures

The hole wavefunctions, the energy levels and the sheet density of a strained p–Si/Si1−xGex/p–Si selectively doped double heterojunction are investigated atT= 0 K, solving the Schrödinger and Poisson equations self-consistently. We present a systematic study taking into account all the modulation parameters involved, i.e. the well width, the spacer thickness and the doping concentration, forx=0.2. We give physical interpretations of the interesting characteristics observed. Our results are in very good agreement with experiment.