Effect of surface bond-order loss on the electronic thermal conductivity of metallic polycrystalline films

The effect of surface bond-order loss on the electronic thermal conductivity of metallic polycrystalline films is examined using Boltzmann transport theory. A modification of the grain boundary potential barrier has been made by adding depressed potential wells of intra-atomic trapping C. Q. Sun, Phys. Rev. B 69, 045105 2004 to both sides of the grain boundaries. Electron scattering by film surfaces is also considered to follow the line of Fuchs’ convention. Results show that the thermal conductivity of the films is sensitive to the film thickness, mean grain size, and Fermi energy. In particular, thermal conductivity increases significantly with the depth of the atomic trapping due to the bond-order loss induced surface bond contraction and associated bond strength gain. © 2005 American Institute of Physics. DOI: 10.1063/1.2139833