Electrodeposition of CdS in the presence of H2SeO3 microadditive at 50 degrees C in an aqueous solution was studied. Addition of H2SeO3 affects the growth of CdS thin films and improves structure ordering, coverage, and stoichiometry. The effect of H2SeO3 is advantageous as allows simultaneously improve the coverage and decrease the thickness of the CdS film during the electrodeposition process. Elemental Se detected in the as-deposited CdS films can be easily removed by a vacuum thermal treatment. The reported approach allows the electrodeposition of uniform polycrystalline photosensitive CdS thin films at reduced temperature. The optimal concentration of the microadditive at given conditions is reported. (C) 2017 Elsevier Ltd. All rights reserved.