It was found that the Fe diffusivity at between 1100 and 1250C could be described by:

D(cm2/s) = 6.2 x 10-3exp[-0.87(eV)/kT]

Solubility and Diffusivity of Gold, Iron, and Copper in Silicon. J.D.Struthers: Journal of Applied Physics, 1956, 27, 1560 and Erratum. J.D.Struthers: Journal of Applied Physics, 1957, 28, 516