Double-exposure holographic interferometry (DEHI) technique was used to study the surface deformation of stainless steel substrate, when cobalt oxide was deposited onto it using dc electrodeposition method. The films were deposited by varying the concentrations of CoCl2 solution and the deposition time. It was observed that interference fringes were localized on the surface of substrate when the hologram was transilluminated. It was further noticed that the fringe spacing changes with solution concentration as well as time of deposition. The thickness of deposited film, mass of cobalt oxide deposited on the substrate and rate of mass deposition were evaluated. (C) 2002 Elsevier Science B.V. All rights reserved.