Tin selenide thin films were deposited potentiostatically from an unstirred aqueous solution containing Sn-EDTA and Na2SeO3 onto indium-doped tin oxide glass substrates. The difference in the structural and compositional properties of the film before and after heat treatment in a nitrogen atmosphere were studied. The as-grown and treated films were characterised using various techniques such as X-ray diffractometry, scanning electron microscopy and energy-dispersive X-ray analysis. Photoactivity of the samples was studied using linear sweep voltammetry. An annealing temperature of 150degreesC was found to be the optimum temperature. (C) 2003 Elsevier B.V. All rights reserved.