Dissociative Diffusion of Gold in Silicon

Abstract

The criterion, previously proposed by one of the authors, for the assumption in the dissociative diffusion that the interstitial atoms (or vacancies) are in thermal equilibrium, is applied to the diffusion of gold in silicon, and it is concluded that the interstitial gold atoms can be assumed to be in thermal equilibrium. Specimens with different thicknesses, oxygen concentrations and dislocation densities, which are sinks and sources of interstitial gold atoms and vacancies, are used in the experiment. The diffusion characteristics of gold are analyzed on the basis of the dissociative mechanism, using the model of fixed and variable sinks and sources of vacancies. Then the assumption of thermal equilibrium of interstitial gold atoms is experimentally verified. The activation energy of self-diffusion of silicon, 4.5 eV, obtained from the analysis of the experimental results, is equal to that obtained from the experiment of dissociative diffussion of nickel in silicon.