Effects of deposition time in chemically deposited ZnS films in acidic solution

• Single layer ZnS thin films were deposited by CBD in acidic solution at 95 °C.
• The effect of deposition time was investigated.
• Coexistence of ZnS and ZnO hexagonal structures for time deposition below 2 h
• Thicker ZnS films were achieved after monolayer deposition for 5 h.
• The highest UV-blue emission observed in thin film deposited at 5 h

We report an experimental study on the synthesis and characterization of zinc sulfide (ZnS) single layer thin films deposited on glass substrates by chemical bath deposition technique in acidic solution. The effect of deposition time on the microstructure, surface morphology, optical absorption, transmittance, and photoluminescence (PL) was investigated by X-ray diffraction (XRD), scanning electronic microscopy (SEM), UV-Vis–NIR spectrophotometry and photoluminescence (PL) spectroscopy. The results showed that the samples exhibit wurtzite structure and their crystal quality is improved by increasing deposition time. The latter, was found to affect the morphology of the thin films as showed by SEM micrographs. The optical measurements revealed a high transparency in the visible range and a dependence of absorption edge and band gap on deposition time. The room temperature PL spectra indicated that all ZnS grown thin films emit a UV and blue light, while the band intensities are found to be dependent on deposition times.