The VO2 films were deposited on the AT-, X-, Y- and Z-SiO2 monocrystalline substrates with the magnetron sputtering. The effects of the substrate crystal planes, (011), (2—10), (100) or (001), on the crystal structure, surface morphology, optical properties and phase transformation characteristics of the VO2 film were investigated. The crystal structure differences among the VO2 films deposited on the four substrates were attributed to the lattice mismatch between the SiO2 monocrystalline substrate and the VO2 film, which led to the generation of internal stress within the VO2 film, causing the VO2 to present a diversity of crystal plane and phase at the interface. Among them, the VO2 film exhibited the M-phase on the AT- and X-SiO2 substrates, while a mixture of the M-phase and the R-phase on the Z- and Y-SiO2 substrates. The complex crystal structure resulted in the various surface morphologies, the VO2 particles on the Z- and Y-SiO2 substrates presented a smaller size and gap, as well as a more uniform distribution than those on the AT- and X-SiO2 substrates. All the VO2 films exhibited the metal-insulator phase transition during both the thermal cycling and the laser irradiation cycling processes. The Z-SiO2 substrate had a positive effect on the phase transition performance of the VO2 film, which got a thermochromic phase transition threshold of 64.62 ℃ and an infrared switching ratio of 78.99% at the wavelength of 2500nm. And its photoinduced phase transition threshold was 36.43W/cm², and its infrared switching ratio reached 59.00% under the 1989 nm laser irradiation.
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