A study was made of self-diffusion and foreign-atom diffusion; especially with regard to Zn, whose diffusion behavior was affected by intrinsic point defects such as Si self-interstitials and vacancies. The diffusion of Zn in dislocation-free material was studied at temperatures of between 1208 and 870C. A special method was used to perform iso-thermal anneals which were as short as a few seconds. It was found that the concentration versus depth profiles that were measured by using spreading resistance techniques could be completely described by simultaneous diffusion via the kick-out and dissociative mechanisms. The evolution of the Zn diffusion with time could be divided into short-, intermediate- and long-term diffusion regimes. The profiles which were associated with the long-term regime were suitable for the extraction of the transport capacities of intrinsic defects, as given by the product of the thermal equilibrium concentration and the diffusion coefficient. The Zn profiles for intermediate diffusion times were shown to be sensitive to the prevailing thermal equilibrium concentrations of Si self-interstitials.

H.Bracht, N.A.Stolwijk, H.Mehrer: Physical Review B, 1995, 52[23], 16542-60