The interaction of laser irradiation with SiOx films and process of decomposition SiOx on SiO2 and Si nanocrystals under the action of laser irradiation are investigated. Using the Comsol Multiphysics software package, the mathematical modeling of temperature distribution in a c-Si wafer and also on it's surface are carried out. It is shown that laser pulses can efficiently warm the samples of crystalline silicon. During the laser pulse of 10 ns with intensity of 52 MW/cm(2) the temperature up to 2100 K can be reached on the sample surface. The experimental investigation of IR spectra of the initial and laser annealed silicon wafer coated with SiOx film confirmed the phase transformation of silicon oxide films. The changing electrical conductivity of films after laser irradiation points at changing of electron traps as a result of the film structure transformation. (C) 2013 Elsevier B.V. All rights reserved.