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B. Dongre, J. Carrete, S. Wen, J. Ma, W. Li, N. Mingo, G.K.H. Madsen:
"Combined treatment of phonon scattering by electrons and point defects explains the thermal conductivity reduction in highly-doped Si";
Journal of Materials Chemistry A, 8 (2020), 1273 - 1278.

The mechanisms causing the reduction in lattice thermal conductivity in highly P- and B-doped Si arelooked into in detail. Scattering rates of phonons by point defects, as well as by electrons, are calculatedfromfirst principles. Lattice thermal conductivities are calculated considering these scatteringmechanisms both individually and together. It is found that at low carrier concentrations andtemperatures phonon scattering by electrons is dominant and can reproduce the experimental thermalconductivity reduction. However, at higher doping concentrations the scattering rates of phonons bypoint defects dominate the ones by electrons except for the lowest phonon frequencies. Consequently,phonon scattering by point defects contributes substantially to the thermal conductivity reduction in Siat defect concentrations above 1019cm 3even at room temperature. Only when, phonon scattering byboth point defects and electrons are taken into account, excellent agreement is obtained with theexperimental values at all temperatures.

http://dx.doi.org/10.1039/c9ta11424f