Proceedings of International Conference on Applied Innovation in IT
2026/03/31, Volume 14, Issue 1, pp.609-617
Data-Driven Gas Sensing Performance of Cdo Thin Films
Hiba Saad Rasheed, Ibtihaj Shukur Abdulfattah, Maryam Ahmed Sabri, Muhaned Zaidi and Israa Akram Abbas Abstract: This study explores how different film thicknesses (250, 300, and 350 nm) of CdO thin films deposit by spray pyrolysis (SP). XRD analysis confirmed the polycrystalline nature, demonstrating a preference for direction towards the (200) plane. Crystallite size increased with thickness. AFM analyses revealed a reduction in surface roughness and grain size with increased thickness, indicating smoother, more uniform films. Optical analysis showed a decrease in both absorbance and bandgap energy (from 2.58 eV to 2.43 eV) as the film thickness increased, due to improved crystallinity and sub-level formation in the band structure. Both extinction coefficient and refractive index exhibited a decline as the film thickness increased, indicating enhanced optical quality and reduced surface defects. Gas sensing performance was evaluated using NO₂ gas. Thinner films (250 nm) exhibited higher sensitivity due to greater surface area and more active adsorption sites. Sensitivity significantly decreased with increased thickness due to a reduced surface-to-volume ratio.
Keywords: Cdo, Thickness, SP Method, Structural Properties, Morphological, Optical, Energy Gap, Sensitivity.
DOI: Under indexing
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