Formation and Rupture of Ag Conductive Bridge in ZrO₂-Based Resistive Switching Memory

ZrO₂-based resistive switching memory has attracted much attention according to its possible application in the next-generation nonvolatile memory. However, the resistive switching mechanism of the ZrO₂-based memory device is still controversial. In this study, the mechanism of the ZrO₂-based memory device is demonstrated that the resistive switching occurs because of the migration of Ag⁺ ions. While a positive voltage is applied, Ag⁺ ions in the ZrO₂ film migrate to connect the Pt bottom electrode, causing the formation of Ag conductive bridge. On the other hand, while a negative voltage is applied, Ag⁺ ions migrate toward the Ag top electrode, leading to the rupture of the Ag conductive bridge. In addition, the resistive switching properties of the ZrO₂-based memory device, such as switching voltages and non-destructive readout property, are also demonstrated in this study. Based on the experimental results, the ZrO₂-based memory device with clear resistive switching mechanism can be possibly used in the next-generation nonvolatile memory.