Deposition of fluorescent ZnO thin film by radio frequency atmospheric pressure plasma

This study presents a simple, efficient, low-cost and catalyst-free strategy for depositing fluorescent zinc oxide (ZnO) thin films on quartz substrates using radio frequency (RF) atmospheric pressure (AP) plasma enhanced chemical vapor deposition (PECVD). Diethylzinc (DEZ) and carbon dioxide (CO 2 ) were employed as the precursor and oxidant, respectively. The plasma discharge characteristics, optical emission spectra (OES), and film growth mechanisms were systematically investigated. ZnO films exhibited high visible-light transmittance (>85%) and strong cyan fluorescence under UV irradiation, attributed to surface defects confirmed by photoluminescence (PL) spectra. X-ray photoelectron spectroscopy (XPS) revealed Zn 2+ as the dominant chemical state, while amorphous structures were identified via X-ray diffraction (XRD) and Raman spectroscopy. A key innovation lies in the atmospheric pressure plasma process, which eliminates the need for high-temperature annealing or vacuum systems, significantly reducing production time and cost compared to conventional methods. Additionally, the influence of CO 2 flow rate on film morphology and optical properties was elucidated, demonstrating tunable fluorescence for potential optoelectronic applications.