An enhanced diffusivity of Sb at very high donor concentrations was found to be related to the appearance of a new impurity complex. On the basis of these observations, and the strong bonding between a vacancy and a donor impurity, a new diffusion mechanism was proposed in which an Sb-vacancy-donor complex was the mobile species.

A.N.Larsen, G.Weyer: Materials Science Forum, 1992, 83-87, 273-8