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Highly oriented VO2 thin films prepared by sol-gel deposition method

Byung-Gyu Chae·Hyun-Tak Kim·Sun-Jin Yun·Bong-Jun Kim·Yong-Wook Lee·Doo-Hyeb Youn·Kwang-Yong Kang
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Abstract

Highly oriented VO2 thin films were grown on sapphire substrates by the sol-gel method that includes a low pressure annealing in an oxygen atmosphere. This reduction process effectively promotes the formation of the VO2 phase over a relatively wide range of pressures below 100 mTorr and temperatures above 400oC. X-ray diffraction analysis showed that as-deposited films crystallize directly to the VO2 phase without passing through intermediate phases. VO2 films have been found to be with [100]- and [010]-preferred orientations on Al2O3(1012) and Al2O3(1010) substrates, respectively. Both films undergo a metal-insulator transition with an abrupt change in resistance, with different transition behaviors observed for the differently oriented films. For the [010]-oriented VO2 films a larger change in resistance of 1.2x10^4 and a lower transition temperature are found compared to the values obtained for the [100]-oriented films.

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Byung-Gyu Chae, Hyun-Tak Kim, Sun-Jin Yun, Bong-Jun Kim, Yong-Wook Lee, Doo-Hyeb Youn, Kwang-Yong Kang. 2005-10-12. Highly oriented VO2 thin films prepared by sol-gel deposition method. https://arxiv.org/abs/cond-mat/0510267

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