The effect of preliminary heat treatment (800C) upon the accumulation and annealing kinetics of thermal donors which formed at 450C in single crystals was investigated by performing 4-point measurements of the resistivity. The activation energies for the generation and annealing of thermal donors were found to increase appreciably after the preliminary heat treatment. The results were explained with regard to the role played by the various phase states of O in as-grown material. An interpretation was proposed which made allowance for the effects of internal elastic stresses, which were created by micro-fluctuations of the O and thermal donor concentrations in the lattice, upon the diffusion coefficient of O atoms. The generation and annealing kinetics of thermal donors were described within the Kaizer-Frisch-Reiss model, with allowance for the locally accelerated (within micro-fluctuations) diffusion of O. The micro-fluctuations involved some 1 to 3% of the total number of O atoms. This low percentage complicated the observation of accelerated O diffusion by direct methods, but was sufficient for thermal donor generation.

Nature of the Nuclei for Thermal Donor Formation in Silicon (or Another Variant of Accelerated Oxygen Diffusion) V.B.Neimash, E.A.Puzenko, A.N.Kabaldin, A.N.Kraichinskii, N.N.Krasko: Fizika i Tekhnika Poluprovodnikov, 1999, 33[12], 1423-7 (Semiconductors, 1999, 33[12], 1279-83)