Characterization of the VO<sub>2</sub> Thin Films Grown on Glass Substrates by MOD

Abstract

This paper describes the deposition of Nb doped vanadium dioxide (VO2) films on a glass substrate by metal organic decomposition (MOD) and their thermochromic properties. The difference in thermochromic properties of VO2 thin films on a glass substrate was investigated with and without a buffer layer of Hf0.5Zr0.5O2 (HZO). The phase transition temperature of VO2 thin film successfully reduced from 83 to 43℃ on a glass substrate with a buffer layer of HZO. Without a buffer layer of HZO, the thermochromic properties of VO2 thin films deteriorated comparing with a buffer layer of HZO. HZO buffer layer effectively suppresses the miniaturization of VO2 crystallite size of thin film due to Nb doping. Moreover, it would block out the diffusion of Al, Na and Ca impurity ions from a glass substrate and the partial oxidation of VO2 thin films judging from XPS O1s spectra and XPS depth profile analysis. We conclude that the insertion of the HZO buffer layer is a useful technique for controlling the transition temperature of VO2 for the smart window applications by MOD.