1. Fabrication and Infrared Optical Properties of Nano Vanadium Dioxide Thin Films
- Author
-
Jian Liu, Yang Fh, Wang Xd, Hu M, Hailong Chen, Ji A, Li Gk, Liang, and Wu Nj
- Subjects
Materials science ,genetic structures ,Annealing (metallurgy) ,Scanning electron microscope ,Analytical chemistry ,eye diseases ,Vanadium oxide ,Crystallinity ,X-ray photoelectron spectroscopy ,Rutile ,Nano ,sense organs ,Physical and Theoretical Chemistry ,Thin film - Abstract
Vanadium dioxide thin films were fabricated by ion beam sputtering on Si3N4/SiO2/Si after a post reductive annealing process in a nitrogen atmosphere. X-ray Diffraction (XRD), scanning electron microscope (SEM), and X-ray photoelectron spectroscopy (XPS) were employed to analyze the effects of post annealing temperature on crystallinity, morphology, and composition of the vanadium oxide thin films. Transmission properties of vanadium dioxide thin films were measured by Fourier transform-infrared (FT-IR) spectroscopy. The results showed that the as-deposited vanadium oxide thin films were composed of non-crystalline V2O5 and a tetragonal rutile VO2. After annealing at 400 degrees C for 2 h, the mixed phase vanadium oxide (VOx) thin film changed its composition and structure to VO2 and had a (011) oriented monoclinic rutile structure. When increasing the temperature to 450 degrees C, nano VO2 thin films with smaller grains were obtained. FT-IR results showed that the transmission contrast factor of the nano VO2 thin film was more than 0.99 and the transmission of smaller grain nano VO2 thin film was near zero at its switched state. Nano VO2 thin film with smaller grains is an ideal material for application in optical switching devices.
- Published
- 2009