Effect of p donors on thermal phonon scattering in SI

2014 Experimental results are presented for the thermal conductivity of P-doped Si over the concentration range 2.5 x 1014 to 1.1 1018 cm-3 in the temperature region 1.5-50 K. In the low concentration range, phonon scattering by isolated P donors is very weak in contrast with that by Group-V donors in Ge and Li donor in Si. This is due to the large valley orbit splitting of the P donor ground state. For samples with donor concentrations higher than 4.7 x 1017 cm-3, thermal résistance becomes larger than that predicted by a simple theory on the basis of phonon scattering by a single donor center. In this concentration range, thermal conductivity has the temperature dependence Tn (n ~ 2) at low temperatures (T ~ 10 K). LE JOURNAL DE PHYSIQUE TOME 37, FtvRiER 1976, Classification Physics Abstracts 8.221