Structural and optical properties of ZnS thin film grown by pulsed electrodeposition

ZnS thin films were grown on indium-tin-oxide coated glass substrates using pulsed electrodeposition and the effect of the deposition temperature on the structural and optical properties of the ZnS films was investigated. Polycrystalline cubic ZnS films were obtained at all the deposition temperatures. At temperatures below 70 C, less dense films were obtained and particle agglomeration was visible. On the other hand, at temperatures above 70 C, more dense films with well-defined grains were obtained. With increasing deposition temperatures, the optical transmittance and bandgap of the ZnS films decreased. These results are attributed to the increase in the thickness of ZnS films and their particle size. The ZnS films grown at 90 C exhibited the highly (200) preferred orientation and n-type conductivity with a wide bandgap of 3.75 eV.