Electrical resistance and Auger electron spectroscopy characteristics of interdiffusion in Au/metal bilayer films

Abstract

The diffusion of copper and cobalt through polycrystalline gold thin films in Au/Co and Au/Cu bilayer structures was studied by measuring the change in electrical resistance and the accumulation of copper or cobalt on the outer surfaces by means of Auger electron spectroscopy. The mass transfer of both copper and cobalt through gold is shown to be dominated by diffusion through the gold grain boundaries. The diffusion activation energies were obtained by the two methods and are compared with previous published data. The importance of the electrical resistance measurements as complementary to the Auger method is demonstrated.