Quantum defect approach for the effect of electron–phonon coupling on impurity recombination in semiconductors

Recombination via impurity states in wide gap semiconductors affected by charge–phonon coupling has been investigated and modeled in the framework of the quantum defect approach. The Huang–Rhys factor being a measure of electron phonon interaction has been calculated for free-to-acceptor and donor–acceptor recombination involving impurity centers with arbitrary ionization energies. The calculations have been performed for ZnSe. The model permits adequate describing of impurity recombination band shape in doped ZnSe.