Effects of the thickness of indium films and the annealing temperature on structural, optical and electrical properties of chemically deposited cadmium zinc sulfide (CdZnS) films were investigated. X-ray diffraction patterns of CdZnS films indicate that the minimum thickness and annealing temperature for the formation of an In2O3 layer, which acts as a barrier preventing the out-diffusion of indium, are 20 nm and 350degreesC, respectively. In2O3 layers give the high optical transmittance due to their transparent properties. As the thickness of indium film and the annealing temperature increase, the conductivity of CdZnS films improves and the lowest resistivity of 0.3 Ohmcm is attained for CdZnS films with 40nm indiurn coating and annealed at 450degreesC. (C) 2002 Published by Elsevier Science B.V.