[1P01-52] Poster Presentation

[1P45] Low-temperature growth of vanadium dioxide thin film on c-Al₂O₃ substrate in reactive sputtering

*Kosuke Kasugai¹, Haruki Sato¹, Yuka Kurosaki¹, Md Suruz Mian¹, Takeo Nakano¹ (1. Seikei University)

Vanadium dioxide (VO₂) shows an insulator-metal transition at around 68 ℃, which can be utilized for various sensors and smart glass applications. Crystal growth of VO₂ requires deposition temperatures above 400 ℃, but lower temperature is desirable. In this study, we aimed to achieve crystal growth at lower temperatures by adjusting the oxygen flow rate during the deposition of VO₂ by reactive DC sputtering (r-DCMS). In the experiments, VO₂ was deposited on c-Al₂O₃ substrates at 300-400 ℃ using r-DCMS. The oxygen flow rate was changed during deposition to alternate between metal and oxide mode of reactive sputtering. The crystallinity of the films was evaluated by XRD, and the temperature dependence of the resistance was measured. The results show that VO₂ crystallizes on the c-Al₂O₃ substrate even at 350 ℃. The VO₂ peak was confirmed by XRD and showed a resistance change of up to 1.5 orders of magnitude depending on temperature.