Pulsed Laser Deposition of VO₂ Single Crystal Thin Films on Sapphire Substrates

Thin films of VO₂ single-crystalline on (0001) sapphire substrates have been prepared by visible pulsed laser ablation technique. The crystal quality and properties of the films are evaluated through electrical resistance measurement, x-ray diffraction (XRD), and Rutherford- backscattering spectroscopy/channeling (RBS/C) analysis. The dependence of the surface electrical resistance of the films on the temperature shows semiconductor-to-metal transitions with the resistance change of 7x10³-2 x 10⁴. The hysteresis widths are from less than 1 to 3 K . XRD and RBS/C data reveal that the films prepared in particular conditions are single-crystalline VO₂ with the (010) planes parallel to the surface of the sapphire substrate.