Revised Shockley–Read–Hall lifetimes for quantum transport modeling

The inclusion of quantization effects on the carrier densities is now the state of the art in modern semiconductor device simulators and yields, for example, quantum-corrected threshold voltages and quantum-mechanical models of the channel mobility. However, the effect of charge quantization on nonradiative thermal generation–recombination has not received much attention. In this article, Shockley–Read–Hall recombination is examined for situations in which electrons and/or holes are confined in semiconductor devices. For the transitions between band states and a single deep level, a previously developed multiphonon description is adopted. It is found that the lifetimes have to be altered due to the same quantized local density of states that also accounts for the carrier distribution. Numerical evaluation of this model for one-dimensional potentials and small phonon energies results in spatially varying lifetime profiles that exhibit two opposite regimes. The additional nonclassical offset of the subband ...