Interdiffusion in thin conductor films — chromium/gold,nickel/gold and chromium silicide/gold

The diffusion of chromium, nickel and chromium silicide into gold has been studied using thin film techniques. Electrical measurements of film diffusion couples were made at several temperatures and these data are related to the interdiffusion of the metals. It was found that the activation energy for resistance changes in the films is somewhat greater than one-half of that for bulk diffusion indicating the predominance of a grain boundary diffusion mechanism; however, a drastically lowered temperature coefficient of resistance also indicates some interdiffusion by lattice diffusion. Under the conditions of these experiments, the chromium, nickel, and chromium silicide diffuse from the substrate through the gold to the outer surface of the gold where they are oxidized.