High quality VO2 thin films synthesized from V2O5 powder for sensitive near-infrared detection

Abstract

Abstract Vapor transport method has been successfully used to synthesize high quality VO2 thin films on SiO2/Si substrate using V2O5 as a precursor in an inert-gas environment. The morphological and structural evolutions of the intermediate phases during the nucleation and growth processes were investigated by SEM and Raman spectroscopy, respectively. The results showed that the conversion of V2O5 powder to VO2 thin films was dominated by a melting-evaporation-nucleation-growth mechanism. Further characterization results demonstrated that the high quality crystals of monoclinic VO2 thin films exhibit a sharp resistance change up to 4 orders of magnitude. In addition, the VO2 thin films exhibited good near-infrared response, high stability, and reproducibility under ambient conditions, which should be promising for sensitive near-infrared detection. Our work not only provided a simple and direct approach to synthesize high quality VO2 thin films with distinct phase transition properties but also demonstrated the possible infrared sensing application in the future.