Boundary scattering of phonons

Abstract
The role of boundary scattering of phonons in reducing the lattice thermal conductivity is investigated in silicon, germanium and silicon-germanium alloy. The theoretical model gives a satisfactory explanation to the reduction in thermal conductivity observed in thin undoped films of silicon compared to bulk material. The magnitude of the reduction in heavily-doped hot-pressed Si-Ge alloys is somewhat less than previously reported and discrepancies still remain between theory and experimental data.