The electrochemical quartz crystal microbalance (EQCM) has been used to study the growth of CuInS2 films by one-step electrodeposition. Films have been grown on SnO2/glass substrate from aqueous solutions of In-2(SO4)(3), CuSO4, and Na2SO3. Differences in the properties and structure of the CuInS(2)films are observed depending on the deposition potential and concentration of precursors. X-ray diffraction shows a CuInS2 phase predominant for films, after annealing at 200 degrees C in nitrogen atmosphere. The composition of the films was studied with X-ray photoelectron spectroscopy (XPS), showing again predominant CuInS2, together with secondary phases Of Cu2O/Cu2S, CuO/CuS, and In2S3 compositions. (c) 2005 Elsevier B.V All rights reserved.