Nanoscale-Thick La_0.7Sr_0.3MnO₃ Films for Memristor Devices with Negative Differential Resistance-Coupled Resistive Switching Behavior

Perovskite semiconductors, as an emerging material, have gained widespread attention in the preparation of memristor devices with resistive switching (RS) behavior due to their excellent properties, such as ion migration, adjustable bandgap, and high OFF/ON ratio. The negative differential resistance (NDR) effect-coupled RS behavior has important prospects for the preparation of multifunctional devices due to its potential to break the limitations of Moore’s law. In this work, the La_0.7Sr_0.3MnO₃ films with different nanoscale thicknesses were prepared on fluorine-doped SnO₂ (FTO) substrates by the radio frequency (RF) magnetron sputtering method as a functional layer of the memristor device. The Ag/La_0.7Sr_0.3MnO₃/FTO memristor device achieves bipolar RS behavior with both nonvolatile memory and NDR effect, and the NDR-coupled RS effect can be successfully regulated by the functional layer thickness and bias voltage range. The conduction mechanism of the NDR-coupled RS phenomenon in the device can be explained by the formation and fracture of metal ion oxygen vacancy (V₀²⁺) conduction paths inside the functional layer. This work provides an important avenue for understanding the multiple physical mechanisms in memristor devices.