High quality VO(2) thin films synthesized from V(2)O(5) powder for sensitive near-infrared detection

Vapor transport method has been successfully used to synthesize high quality VO(2) thin films on SiO(2)/Si substrate using V(2)O(5) 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 V(2)O(5) powder to VO(2) thin films was dominated by a melting-evaporation-nucleation-growth mechanism. Further characterization results demonstrated that the high quality crystals of monoclinic VO(2) thin films exhibit a sharp resistance change up to 4 orders of magnitude. In addition, the VO(2) 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 VO(2) thin films with distinct phase transition properties but also demonstrated the possible infrared sensing application in the future.