Influence of deposition time on ZnS thin film growth over SiO2 and glass substrates

ZnS thin films have been deposited on glass and SiO2 substrates in an alkaline solution using the chemical bath deposition method. The reaction solution is prepared using zinc acetate, thiourea, tri-ethanolamine and tri-sodium citrate at pH close to 10.0. Different deposition times 30, 60 and 90 min, were selected to study the performance of ZnS thin films. According to the results, the surface morphology was affected by the type of substrate, showing different rates of growth for each one of them. The growth of ZnS on glass was more homogeneous for the material at 90 min of reaction showing a high transmission, >80% in the spectra range from 300 nm to 800 nm, and the optical band gap of the sample was about 3.62 eV. (C) 2013 Elsevier B.V. All rights reserved.