Strain-dependent phase-change devices based on vanadium dioxide thin films on flexible glass substrates

Smart materials offering tunable electrical properties in response to external stimuli are in high demand for their usage in reconfigurable electronics. This study reports the stability and reversibility of insulator-to-metal transition (IMT) in a vanadium dioxide (VO2) thin film grown on flexible glass substrates under the external strain. The systematic application of the external strain was used to demonstrate red and blue shifts in the Raman spectra (ωV-O) and the corresponding change in the IMT critical temperature. The effects of externally applied tensile strain on the electrical resistance of the VO2 thin film were discussed concerning the stability and repeatability of the IMT. We demonstrated that the electrical performance of the thin film was nondegradable, although the sample was subjected to multiple cycles of tensile strain. Moreover, these results not only provide essential knowledge for understanding the correlation between the external strain and physical properties of VO2 thin films but also suggest their applicability as strain-dependent phase-change devices.