Strain-Induced Modulation of Resistive Switching Temperature in Epitaxial VO2 Thin Films on Flexible Synthetic Mica

The resistive switching temperature associated with the metal-insulator transition (MIT) of epitaxial VO2 thin films grown on flexible synthetic mica was modulated by bending stress. The resistive switching temperature of polycrystalline VO2 and V2O5 thin films, initially grown on synthetic mica without a buffer layer, was observed not to shift with bending stress. By inserting a SnO2 buffer layer, epitaxial growth of the VO2 (010) thin film was achieved, and the MIT temperature was found to vary with the bending stress. Thus, it was revealed that the bending response of the VO2 thin film depends on the presence or absence of the SnO2 buffer layer. The bending stress applied a maximum in-plane tensile strain of 0.077%, resulting in a high-temperature shift of 2.3 degrees C during heating and 1.8 degrees C during cooling. After 104 bending cycles at a radius of curvature R = 10 mm, it was demonstrated that the epitaxial VO2 thin film exhibits resistive switching temperature associated with MIT.