The effect of the charge state of Fe upon its diffusivity in p-type material was studied by using capacitance-voltage and deep-level transient spectroscopic methods. It was found that the migration enthalpies of positive and neutral Fe were equal to 0.92 and 0.56eV, respectively (table 42). A disagreement between the predicted and observed results was explained in terms of the diffusion path, elastic strain and Coulombic interaction for various charge states.

Iron Diffusivity in Silicon: Impact of Charge State. S.V.Koveshnikov, G.A.Rozgonyi: Applied Physics Letters, 1995, 66[7], 860-2