Synthesis and investigation of pure and Ba-ZnO thin films obtained by spray pyrolysis

Author : Eng. Pavlina Bancheva-Koleva

Abstract : Currently, ZnO is among several semiconductor oxides, such as MoO₃, SnO₂, etc. that attract significant scientific interest due to their potential applications in solar cells, high-temperature thermoelectric devices, gas sensors, laser diodes, and more. ZnO also offers advantages such as low deposition temperature, affordability, abundant availability, high exciton binding energy, and non-toxicity. The focus of this study is to examine how barium doping affects the structural, morphological, and optical properties of ZnO. ZnO thin films, both undoped and doped with barium up to 8 mol%, were prepared on glass and silicon substrates using the spray pyrolysis method. X-ray diffraction (XRD) analysis confirmed that the films exhibit a polycrystalline structure with a hexagonal phase. Profilometry measurements showed that the film thickness ranges from 100 nm to 200 nm. Scanning electron microscopy (SEM) images revealed smooth, uniform surfaces composed of densely packed nanocrystalline grains. Atomic force microscopy (AFM) was used to determine the root mean square (RMS) roughness for undoped and barium-doped ZnO films (0 mol%, 4 mol%, and 8 mol%) respectively. Increasing barium content leads to a reduction in film transmittance, while the optical band gap of the films increases with higher indium incorporation.

Keywords : Thin films, ZnO, spray pyrolysis.

Conference Name : International Conference on Thin Films Engineering and Materials Applications (ICTFEMA-26)

Conference Place : Kowloon City, Hong Kong

Conference Date : 5th Mar 2026