The occurrence of enhanced interdiffusion at the interface was studied. Ions of Ar were implanted to doses which ranged from 2 x 1013 to 5 x 1014/cm2, and the samples were then rapidly thermally annealed (950C, 30s). It was found that the degree of intermixing decreased from the surface towards the projected ion range, and was a function of the implantation dose. It was suggested that this variation arose from the coalescence of some of the excess vacancies into extended defects, so that they were then unavailable to the enhanced diffusion mechanism. By assuming that the concentration of mobile vacancies at a given depth was proportional to the electronic energy of the ion, and inversely proportional to the nuclear energy loss of the ion, predictions were obtained which were in good agreement with the experimental results.

K.B.Kahen, D.L.Peterson, G.Rajeswaran: Journal of Applied Physics, 1990, 68[5], 2087-90