Structural, Optical, and Photoconductive Properties of Slurry-Coated Cu0.2Zn0.8S Film

In this study, a slurry-coating procedure was successfully employed to deposit a Cu0.2Zn0.8S film on glass substrates. X-ray diffraction (XRD) and Raman spectroscopy analyses confirmed the formation of a polycrystalline, phase-pure cubic structure. Scanning electron microscopy (SEM) revealed a continuous surface coverage with uniform grain agglomeration alongside the presence of thermal-stress-induced micro-cracks. From the diffuse reflectance spectrum, an optical absorption edge was observed at approximately 331 nm, corresponding to a direct optical band gap of 3.75 eV. To evaluate the material’s suitability for optoelectronic components, electrical conductivity measurements were performed using a two-probe technique under both dark and constant illumination conditions over a temperature range of 300–473 K. The film exhibited a clear semiconducting nature governed by thermal activation, displaying a steady-state photosensitivity ratio (σph/σd) of approximately 9.0. These findings demonstrate that the slurry-coated Cu0.2Zn0.8S film combines structural purity with favorable optoelectronic properties, highlighting its strong intrinsic photo-response and its potential utility as a baseline material for future photoconductive and optoelectronic applications.