Tailoring Optoelectronic Properties of Ag₂O Thin Films via Oxygen-Assisted Electron Beam Evaporation and Thermal Annealing

Silver oxide (Ag₂O) thin films were deposited on glass substrates using oxygen-assisted electron beam evaporation (1.0 × 10² Pa) and annealed at 100, 200, and 300 °C. X-ray diffraction analysis confirmed the formation of a face-centered cubic (FCC) structure with enhanced crystallinity at higher annealing temperatures. The crystallite size decreased from 39.15 to 33.05 nm, accompanied by an increase in lattice strain from 0.0018 to 0.0046. TEM analysis revealed particle sizes in the range of 42–51 nm, consistent with XRD results. Optical studies showed strong absorption in the visible region (480–546 nm), semi-transparent behavior, and an increase in optical band gap from 1.78 to 1.96 eV with annealing temperature. The refractive index also increased from 2.03 to 2.71, indicating improved optical density. EDAX confirmed the stoichiometric composition of Ag and O without impurities. AFM analysis showed a smooth surface with an average roughness of 4.92 nm. Electrical measurements demonstrated enhanced conductivity under oxygen conditions. These results demonstrate that annealing enhances the crystallinity, optical band gap (1.78–1.96 eV), and refractive index (2.03–2.71) of Ag₂O thin films, indicating their potential for optoelectronic and photonic device applications.