The misfit dislocations which were introduced into (001), (111) or (110) wafers by B diffusion were found to nucleate from the diffusion surface; as half-loops with Burgers vectors that were inclined with respect to the surface. The expansion of the half-loop on its glide plane left a 60 misfit dislocation in the diffusion front. The numerous dislocation reaction products which were the result of interactions among the half-loops during expansion were characterized by using cross-sectional and plan-view transmission electron microscopy. It was found that dislocations with a density of the order of 108/cm2 were distributed mainly in a region that was a certain depth below the surface; thus leaving the top region essentially dislocation free. The misfit dislocations that nucleated from the surface were insufficient to relax all of the strain in the diffused layer.

X.J.Ning: Philosophical Magazine A, 1997, 75[1], 115-35