Study of the structural, morphological and optical properties of sprayed In₂S₃:Cl thin films

Thin films of chlorine doped indium sulfide (In₂S₃:Cl) have been elaborated on glass substrates using chemical spray pyrolysis (CSP). Analysis by X-ray diffraction (XRD) and Raman spectroscopy confirm the formation of a cubic β-In₂S₃ material without any secondary phases. The study by Atomic Force Microscopy (AFM) reveals that the surface roughness increases with the level of doping. In the visible and near infrared regions, transmission reaches 80%. The refractive index (n) is affected by the change in doping concentration. Using the Wemple-DiDomenico model some optical parameters such as: single oscillator energy (E₀), dispersion energy (E_d) and high frequency dielectric constant (ε_∞) were determined. Optical conductivities were also estimated. PL spectroscopy shows a high degree of reversibility with respect to temperature changes as well as it is observed that films present seven emissions related to In₂S₃ defects.