Porous silicon layer was formed by electrochemical anodization on n- and p-type silicon surface. Thereafter n-type TiC(1.98) and ZnO < AI > thin films were deposited onto porous silicon surface by electron-beam evaporation and magnetron sputtering, respectively. A Pt catalytic layer and Au electrical contacts for further electrical measurements were deposited by ion-beam sputtering. Changes in sensitivity versus time of obtained structures were examined for different concentrations of hydrogen gas and propane-butane mixture. High sensitivity and selectivity to hydrogen gas was detected. All measurements were carried out at 40 degrees C. (c) 2008 Elsevier B.V. All rights reserved.