Significant reduction of lattice thermal conductivity by electron-phonon interaction in silicon with high carrier concentrations: a first-principles study

摘要

Electron-phonon interaction has been well known to create major resistance toelectron transport in metals and semiconductors, whereas less studies weredirected to its effect on the phonon transport, especially in semiconductors.We calculate the phonon lifetimes due to scattering with electrons (or holes),combine them with the intrinsic lifetimes due to the anharmonic phonon-phononinteraction, all from first-principles, and evaluate the effect of theelectron-phonon interaction on the lattice thermal conductivity of silicon.Unexpectedly, we find a significant reduction of the lattice thermalconductivity at room temperature as the carrier concentration goes above 1e19cm-3 (the reduction reaches up to 45% in p-type silicon at around 1e21 cm-3), arange of great technological relevance to thermoelectric materials.