Theory of the electronic properties of δ-doped layers withDXcenters in semiconductor heterostructures

We attempt to build a flexible and accurate theoretical model for the electronic properties of selectively doped semiconductor heterostructures based on a two-band k{·}p effective-mass-approximation Hamiltonian that includes nonparabolicity, stress, piezoelectric, finite-temperature, many-body, and DX-center effects. We present quantitative self-consistent results for a variety of {δ}-modulation-doped semiconductor heterostructures with the aim of optimizing the electronic density in the active region as a function of configuration, including [001] and [111] interfaces for device applications. The presence of DX centers leads to the prediction of saturation of the carrier density with a characteristic capacitance discontinuity as the {δ}-doping concentration is increased. Calculated differential capacitance C-V curves indicate that spatial charge-density inhomogeneities, but not subband depopulation, lead to sharp steps in the capacitance as the gate voltage is increased.