Arsenic enhanced or retarded diffusion was observed by overlapping the dopant region with, respectively, interstitial-rich and vacancy-rich regions produced by Si implantation. Enhanced diffusion could be attributed to interstitial-mediated diffusion during post-implantation annealing. Two possible mechanisms for diffusion retardation, interstitial-vacancy recombination and dopant clustering, were analyzed in additional experiments. The point defect engineering approach demonstrated here could be applied to the fabrication of n-type ultra-shallow junctions.

Enhanced and Retarded Diffusion of Arsenic in Silicon by Point Defect Engineering. N.Kong, S.K.Banerjee, T.A.Kirichenko, S.G.H.Anderson, M.C.Foisy: Applied Physics Letters, 2007, 90[6], 062107