Growth of nanostructured thin films of Zn1−xVxO using rf-magnetron sputtering with low and high vanadium loading: Physico-chemical characterization, optical and electrical properties evaluation

Abstract

The present study reports on the structural, morphological, optical and electrical properties of Zn1−xVxO (0 ≥ x ≥ 0.30) thin films. These films of ∼ 200 to 240 nm thickness with low and high vanadium loading, were grown by rf-magnetron sputtering on Si (100) and glass substrates at room temperature (RT) and 200 °C, respectively, using Zn1−xVxO nanopowder like targets. In regard to this, it should be noted that Zn1−xVxO nanopowder were successfully synthesized by sol-gel process. The controlled growth of these films is optimized by structural, morphological, optical and electrical characterization, and thus is confirmed by several techniques such as X-Ray Diffraction (XRD), Transmission Electron Microscopy (TEM), Energy Dispersive X-ray Spectroscopy (EDS), Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM). UV-Vis-NIR study of the samples shows a variable behavior (optical bandgap energy) depending on the vanadium content and also according to the temperature of the thin-layers deposition, which can be explained by the formation of the excited states. The resistivity of these thin films was then assessed. An increased resistivity was observed for layers developed with high vanadium loading at 200 °C. These remarkable properties of thin films developed through this research are expected to provide potential applications in the TCO and buffer-layers.