Temperature-Dependent Optical Properties of Spray-Pyrolyzed Cadmium Oxide Thin Films
DOI:
https://doi.org/10.53560/PPASA(63-2)715Keywords:
Cadmium Oxide (CdO), Optical Properties, Spray Pyrolysis Deposition (SPD), Energy Gap, X-ray DiffractionAbstract
In present study, Cadmium Oxide (CdO) films have been prepared using spray pyrolysis deposition (SPD) at different substrate temperatures (350, 450, and 550 °C) with glass substrate. Thickness of these films prepared was approximately 400 ± 10 nm. XRD diffraction analysis revealed the CdO were polycrystalline and cubic, exhibiting grain sizes ranging from 198.5 to 229.8 nm. The effect of varying substrate temperatures on the optical properties of CdO was analyzed by examining transmittance and absorption spectra within the 300 to 900 nm range. The transmittance of CdO increases with increasing the substrate temperature. The energy gap for direct transitions was determined to range between 2.4 and 2.5 electron volts. It was found that varying the substrate temperature affects CdO films, increasing its transmittance and energy gap, and decreasing its reflectivity, absorption coefficient, extinction coefficient, real parts and imaginary parts of the dielectric constant, and refractive index. Based on these observed properties, thin films fabricated in this way can be used in sensors and catalysts, or in solar cells.
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