THICKNESS-DEPENDENT STRUCTURAL, OPTICAL, AND DC ELECTRICAL BEHAVIOR OF SOTF COATING DEPOSITED BY USP TECHNIQUE

In this research paper, stannic oxide thin films (SOTF) of variant thicknesses (d) were prepared at a substrate temperature of 35[Formula: see text]C via the ultrasonic spray pyrolysis (USP) method. Different characterization techniques were employed to understand the thickness dependency of structural, optical, and DC electrical behavior of SOTF. The SEM micrographs displayed a uniform surface with irregular sphere-shaped particles. The X-ray diffraction (XRD) patterns illustrated that the SOTF are polycrystalline having a tetragonal rutile structure and the diffraction peak intensity increases with d. Thickness-dependent XRD parameters were calculated for these SOTFs. In optical analysis, transmittance% decreased with d but increased exponentially with the wavelength, [Formula: see text] while a counter behavior was observed both for d and [Formula: see text] in the case of reflectance%. The absorption coefficient and refractive index increased with the increase of d and photon energy in an energy region of 2–4[Formula: see text]eV. Direct optical bandgap energy of SOTF was found to be 2.82–3.70[Formula: see text]eV for the varied thickness of 147–450[Formula: see text]nm. Alteration of other optical parameters was also discussed. DC electrical analysis revealed that the electrical conductivity of SOTF was decreased rapidly with d but sheet resistance increased linearly.