Authors : Madhukeswara R. S.

Volume/Issue : Volume 11 - 2026, Issue 6 - June

Google Scholar : https://tinyurl.com/narrycba

Scribd : https://tinyurl.com/5n8behhz

DOI : https://doi.org/10.38124/ijisrt/26jun530

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Abstract : The effect of air annealing on the optical characteristics of CuO thin films produced on glass substrates by Chemical Bath Deposition (CBD) process was studied by annealing the films in ambient air at different temperatures. The films as deposited were air annealed at temperatures of 350°C and 450°C for one hour. Optical properties of the films were studied by UV-Visible spectroscopy in the wavelength range of 200-1200 nm. The results showed that the air annealing has a substantial effect on the optical behaviour of CuO thin films. As the annealing temperature increased, significant changes in the absorbance and transmittance spectra were observed, indicating an enhancement in the film quality and crystallinity. The absorption coefficient was observed to increase with annealing temperature due to increased grain development and decreased flaw density. The optical band gap was calculated using the Tauc’s relation. The band gap energy was gradually changed with increasing annealing temperature. These modifications can be explained by structural reorganization, decrease of lattice defects and enhanced stoichiometry of CuO films during the annealing. This work shows that air annealing is a promising post-deposition procedure for tuning the optical characteristics of CBD produced CuO thin films for their application in photovoltaic devices, photodetector and optoelectronic systems. The results provide useful information on how to optimize the annealing conditions for obtaining better optical performance in CuO-based thin-film devices.

Keywords : CuO Thin Films, Chemical Bath Deposition, Air Annealing, Optical Properties, Optical Band Gap

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