Grain boundary sliding in thin substrate-bonded Al films☆

Abstract A systematic investigation of the anelastic relaxation of thin Al films on Si substrates has been carried out. It was found that the relaxation in both bulk and thin film materials can be explained by a model involving the glide of grain boundaries (GBs). The mass transport necessary for the glide occurs via GB diffusion in thin films and via lattice diffusion in bulk material, the different behaviour being due to the smaller (by more than two orders of magnitude) grains in the films. Internal friction thus provides a technique to measure diffusional parameters of GB diffusion in thin films.