Indium oxide and indium-cobalt oxide thin films have been successfully prepared by direct UV irradiation of amorphous films of beta-diketonate complexes on Si(100) substrates. Deposited films were characterized by X-ray diffraction, Auger electron spectroscopy and X-ray photoelectron spectroscopy. The surface morphology of the films, examined by atomic force microscopy and scanning electron microscopy, revealed that mixed indium-cobalt oxide films are much smoother than In2O3 films, with rims surface roughness of 7.24 and 26.1 nm, respectively. (C) 2005 Elsevier Ltd. All rights reserved.