Enhanced CuO Thin Film Growth via an Optimized Aerosol Droplet Method: Thermal Effects and Structural Evaluation

Abstract The scalable production of high‐quality copper oxide (CuO) thin films remains challenging for semiconductor and gas sensor applications. This study presents an optimized aerosol droplet method (AMD) that enhances film uniformity and crystallinity through improved substrate positioning and aerosol dynamics. Compared to conventional aerosol chemical vapor deposition (ACVD), the modified AMD configuration extends droplet trajectories, reducing thickness variation by 30–50% and enhancing structural ordering. Systematic analysis of substrate temperature effects (100–300°C) shows higher temperatures decrease film thickness and microstrain while increasing crystallite size and improving optical properties. X‐ray diffraction (XRD) confirms phase‐pure monoclinic CuO with enhanced crystallinity, and scanning electron microscopy (SEM) demonstrates temperature‐controlled morphological evolution. Energy‐dispersive X‐ray spectroscopy (EDX) confirms uniform elemental distribution. Raman and photoluminescence (PL) spectroscopy reveal temperature‐dependent defect states and bandgap narrowing from 1.6 to 1.5 eV, accompanied by variations in Urbach energy and dielectric constants. The results demonstrate AMD as an efficient, scalable approach for fabricating high‐performance CuO thin films with tunable structural and optoelectronic properties, making them ideal for advanced gas sensing and optoelectronic devices.