The diffusion of Fe in monocrystalline material was found to be a rapid process at semiconductor-device fabrication temperatures. Electronic-grade Ge samples were coated with a radioactive surface source and short-term annealed in a lamp furnace at 600 to 900C. The diffusion coefficients were determined from the penetration profiles of the radioisotopes, 59Fe, and could be described by the expression:

D (cm2/s) = 1.9 x 10-1 exp[-1.22(eV)/kT]

The results were interpreted within the framework of interstitial-substitutional diffusion.

L.Lerner, N.A.Stolwijk: Applied Physics Letters, 2008, 93[3], 032107