Impact of Ar:O2gas flow ratios on microstructure and optical characteristics of CeO2-doped ZnO thin films by magnetron sputtering

Abstract

In this study, a radio frequency magnetron sputtering technique was applied to deposit eminently oriented ZnO thin films on stainless steel (SS316L). The effect of different ratios (Ar:O2) of gas flow [(20:0), (15:5), (10:10), (5:15), (0:20)] on optical and structural properties of CeO2 doped ZnO thin films has been examined. The increase in grain size of thin films was observed with a partial increase in the Ar:O2 sputtering gas at substrate temperature of 673 K. The average surface roughness of the thin films has increased with sputtering gas. The photoluminescence peak exhibited a broad green–yellow band spiked at 467 nm for all the samples of CeO2 doped ZnO thin films and a wide band of visible light focused in the 500–600 nm range. Intensity reduction of deep level emission peaks of ZnO films was observed. The refractive index of undoped and CeO2 doped ZnO thin films with various sputtering gas ratios (Ar:O2) were also investigated. The optimized argon gas flow rate findings allow us to choose the deposition conditions for CeO2 doped ZnO thin films for solar thermal applications.