Metallic filament domain dynamics-induced abrupt resistive switching characteristics with small hysteresis in two dimensional-crystalline VO2 films

The domain configurations in vanadium dioxide (VO2) that are interfacing with a substrate play an important role, particularly in the electronic property, due to the interface-dependent strain induction and phase coexistence across the metal-insulator transition (MIT) process. Here, we demonstrate an abrupt resistive switching behavior with a small hysteresis by utilizing the strain-induced metallic filament domains in VO2 films with puzzle-like two-dimensional single crystalline domains (2D-crystalline VO2 films), which are synthesized on a SiO2 layer. We find that an anisotropic tensile strain induced at the 2D-crystalline VO2 films /SiO2 interfaces leads to the preferential formation and propagation of metallic stripe domains along the in-plane growth direction across the MIT. We also demonstrate that based on simultaneous in situ observations of electrical characteristics and phase evolution in the 2D-crystalline VO2 films, the abrupt transition with a narrow hysteresis width (<4 °C) is attributed to the thermally activated and reversible evolution of metallic stripe domains acting as a conducting filament channel within an insulating phase, which is associated with anisotropic strain distribution. Moreover, we show that these experimental results are consistent with the theoretical analysis based on a parallel resistor model. In addition, we further demonstrate thermally-triggered abrupt and reversible resistive switching performance of the 2D-crystalline VO2 film, maintaining stable for 500 switching cycles. These results provide an important strategy to modulate and utilize the unique MIT hysteresis behavior properties through controlling the configuration of metallic and insulating stripe domains in the 2D-crystalline structure of VO2 for the development of high-performance VO2 based electrical devices.