Fast Responsive of Ultraviolet-Light VO2 Flexible Photodetector

Vanadium dioxide (VO₂) is a useful and promising material for the applications in electrical, tunable photonic crystals, field effect transistor (FET), temperature-sensing device, and optical switching device because the material possesses unique electrical and optical properties. In this work, the single crystal VO₂ nanorods/microrods were grown on SiO₂/Si(100) substrate at 850^oC. The SiO₂ layer was acted as self-catalysts. A high-resolution transmission electron microscopy (HRTEM) image indicates that the nanorods grew along the [100] axis as a single crystal. An individual VO₂ microrod was bonded at its ends on a flexible polystyrene substrate as a flexible photodetector, which exhibited an excellent optical switching property for the detection of ultraviolet-light radiation. The external quantum efficiency (EQE) and detectivity are 2E^7 and 1.2E^12 Jones, respectively. The response time was 0.2 second.