Structural and Optical Properties of Chalcogenide WS2 Thin Film

To fabricate the nanocrystalline thin film of WS2, thiourea (CH4N2S), and sodium tungstate (Na2WO4) were used as the sources of sulfide and tungsten, respectively. The chemical bath deposition (CBD) method was employed for developing the chalcogenide WS2 nanocrystalline thin film on p-Si (Silicon) substrate. To validate the results, X-ray diffraction (XRD), ultraviolet—visible (UV—Vis) spectroscopy, and I-V characteristics have been applied systematically to examine the structural, optical, and electrical properties, respectively. XRD results confirmed the formation of a polycrystalline hexagonal phase in the fabricated thin film. The optical absorption spectra show an absorption peak at ~ 305 nm, which lies in the ultraviolet range of the EM spectrum (electromagnetic spectrum), the band gap calculated using Tauc’s plot was found to be ~2.50 eV. The transport properties across the junction of the interfacial structure were performed via measurement of current—voltage (I-V) characteristics. The photo response characteristics for the WS2/p-Si structure were also recorded to investigate the potential usage in the photodetector applications.