Pure zinc oxide (ZnO) thin films were successfully synthesized using a chemical deposition technique on glass substrates to investigate their structural and optical properties. The structural characteristics of the films were examined by X-ray diffraction (XRD), which confirmed the formation of a single-phase hexagonal wurtzite ZnO structure with good crystallinity and a preferred orientation along the (002) plane. The calculated lattice parameters were found to be in close agreement with standard ZnO values, indicating low structural distortion and high phase purity. Microstructural parameters such as crystallite size, lattice strain, and dislocation density revealed that the films possess uniform grain growth and minimal defect concentration. Optical properties were studied using UV–Visible spectroscopy in the wavelength range of 300–800 nm. The ZnO thin films exhibited high optical transparency in the visible region with a sharp absorption edge in the ultraviolet region. The optical band gap was estimated using Tauc’s plot, assuming a direct allowed transition, and was found to be approximately 3.27 eV. The observed band gap value is consistent with bulk ZnO and suggests good optical quality of the deposited films. The combination of high crystallinity, wide band gap, and optical transparency makes pure ZnO thin films promising candidates for applications in optoelectronic devices, transparent electrodes, and gas sensing applications.

Keywords: - Pure ZnO thin films, Structural properties, Optical properties, X-ray diffraction (XRD), UV–Visible spectroscopy, Optical band gap, Wurtzite structure