Chemical-bath deposition of ZnSe thin films from NH3/NH2-NH2/SeC(NH2)(2)/Na2SO3/ZnSO4 solutions has been studied. The effect of various process parameters on the growth and the film quality is presented. A first approach to a mechanistic interpretation of the chemical process, based on the influence of the process parameters on the film growth rate, is reported. The structural, optical, chemical, and electrical properties of the ZnSe thin films deposited by this method have been studied. The electron diffraction (EDS) analysis shows that the films are microcrystalline with mixed cubic and hexagonal structure. EDS analysis has demonstrated that the films are highly stoichiometric. Scanning electron microscopy, atomic force microscopy, and x-ray photoelectron spectroscoy studies of the ZnSe thin films deposited by this method show that the films are continuous and homogeneous. Optical measurements have allowed us to detect the presence of the spin-orbit splitting effect in this material. Electrical conductivity measurements have shown the highly resistive nature of these films (rho approximate to 10(9) Ohm cm).