Fabrication and Characterization of Nanocrystalline VO2Thin Films

Nanocrystalline VO 2 films with phase transition temperature 34 degrees C have been fabricated on Si 3 N 4 -film-coated silicon and quartz substrates by argon-annealing films of metastable VO 2 (B). The original VO 2 (B) films are obtained by ion beam sputtering in an argon-oxygen atmosphere at 200 degrees C. The nanocrystalline VO 2 films exhibit strong changes in electrical and optical properties when a phase transition is completed. The phase transition temperature in the as-fabricated samples is about 34 degrees C, which is smaller in comparison with 68 degrees C in the single-crystalline VO 2 material. A lower phase transition temperature is favorable for device applications such as smart window coating and low power consumption optical switching.