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

Abstract

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.

Organic Memory and Memristors: From Mechanisms, Materials to Devices

“…[37] There are many mechanisms proposed to explain different types of memories and memristors, including charge transfer between electron-donor to electronacceptor, [121][122][123][124] charge trapping and de-trapping by the organic molecules, nanoparticles, and defects, [125][126][127][128][129][130] conformational reconfiguration of the small molecules, polymer backbone and pendant unities, [131,132] solid-state electrochemical redox reaction of the metallic and organic species, [133][134] pyrolysis and carbonization of the organic materials, [135][136][137][138][139] ion migration and filamentary conduction. [140][141][142][143] Most of them are induced by an electric field, while pyrolysis and carbonization are the results of Joule heating caused by thermochemical. To explain the charge carrier transport in each resistance state, many well-established conduction models should be taken into consideration, such as the Schottky emission, thermionic emission, Ohmic conduction, ionic conduction, space-charge-limited current, tunneling current, and so on.…”

“…In addition to being used as dopants and charge trapping centers in polymer films, cations (whether cations or anions) can move and migrate through the insulating layer under an external electric field. [33,142,143] For example, when silver or copper is used as the electrode material in polymer devices, the active metal atoms can be electrochemically oxidized (or ionized) to Ag + /Cu 2+ ions (Figure 4f). The cations will be injected from the electrode/ polymer interface into the insulating layer and then migrate to the cathode, where electrons are injected into the cathode to maintain the electrical neutrality of the device.…”

Atomic Layer Deposition of W:Al2O3 Nanocomposite Films with Tunable Resistivity

“…Thin film materials comprised of blended conducting and insulating components have been utilized in a wide variety of applications including resistive layers for electron multipliers such as microchannel plates,1–3 resistive memories,4–8 electro‐chromic devices,9–15 biomedical devices,16–18 and charge‐dissipating coatings on micro‐electromechanical systems (MEMS) devices 19–23. The physical and electrical properties of composite thin films can be tailored by adjusting the relative proportions of the constituent materials.…”

Complementary bipolar resistive switching behavior in lithium titanate memory device

“…The very low RESET and SET voltages were usually observed in Ag-based ECM memristors, indicating the Ag ions as super-fast migrating species in various oxides. 19,20) The gradual RESET process is observed in our device, which might correspond to the thinning effect of the conducting filament. As the device turned into HRS after a negative bias sweep in the BRS mode, the negative bias sweep could be applied twice.…”