The electrical deactivation of As was studied with regard to its effect upon enhanced diffusion in structures which consisted of a buried B layer, as an interstitial-detector, and a fully activated As-doped laser-annealed surface layer. As these structures were annealed at temperatures of between 500 and 750C, the As in the surface layer was deactivated and enhanced diffusion was observed in the buried B layer. A study revealed that the enhanced diffusion transient and the deactivation transient were similar; thus indicating a strong correlation between these phenomena. The dependence upon concentration exhibited a maximum enhanced diffusion for concentrations, of initially active As, of between 3 x 1020 and 4 x 1020/cm3. When above these concentrations, the large supersaturations of interstitials nucleated dislocation loops and lowered the overall enhancement which was measured in the buried B layer. Enhanced diffusion was observed, even at temperatures as low as 500C. These data constituted convincing evidence that the enhanced diffusion which was observed was due to the deactivation of As. It was proposed that As deactivation created small clusters of various sizes around a vacancy, with the injection of an associated interstitial into the bulk.

Arsenic Deactivation-Enhanced Diffusion. P.M.Rousseau, P.B.Griffin, W.T.Fang, J.D.Plummer: Journal of Applied Physics, 1998, 84[7], 3593-6002