The Nature of Lithium-Ion Transport in Low Power Consumption LiFePO4 Resistive Memory with Graphite as Electrode

Lithium-ion migration modulated by electric field in carbon-based materials has been reported extensively in lithium-ion batteries, which will also offer potential application in ion-migration-related resistive switching (RS) memories. Inspired by this, lithium iron phosphate (LiFePO4)-based RS memory (Au/LiFePO4/G) is developed with Au and graphite sheet as electrodes. The devices can be operated with a low power consumption (<30 mu W) by controlling the compliance currents. The RS mechanism is ascribed to lithium concentration-related reversible conductivity switching inLiFePO(4) due to lithium ions insertion/extraction through the graphite electrode as verified by temperature-dependent resistance, time-of-flight secondary ion mass spectrometry, and Raman spectra. As indicated by the experiments, LiFePO4 is potentially useful for future low power nonvolatile memory applications.