It is proposed that the scattering of phonons by donors in germanium at low temperatures results from the large effect of strain on the energy of an electron in a hydrogen-like donor state. A calculation of the thermal conductivity with this scattering mechanism is presented. Reasonable agreement with the following features of the observed thermal conductivity is obtained: the very large scattering power of donors, the difference between the scattering powers of antimony and arsenic, a temperature dependence of thermal conductivity stronger than $T^3$, and a dependence of the scattering on number of occupied donors rather than on the total impurity concentration.

• Received 21 November 1960

DOI:https://doi.org/10.1103/PhysRev.122.1171