Bipolar resistive switching behavior and endurance in RF-sputtered bilayer HfO₂/ ZrO₂ resistive random access memory

This study presents a novel bilayer resistive random access memory ( RRAM) device utilizing hafnium dioxide ( HfO2) and zirconium dioxide ( ZrO2) layers. By introducing an HfO2 interfacial layer on top of the ZrO2 layer, the device exhibits remarkable stability and uniformity in bipolar resistance switching (RS) behavior. The bilayer device demonstrates several favorable switching characteristics, including a significantly increased on state to off state resistance ratio of approximately 10(2), improved endurance with over 10(4) cycles, and long-term data retention exceeding 10(5) s at room temperature. The presence of oxygen vacancies (VOs) in both dielectric layers was determined using X-ray photoelectron spectroscopy. Overall, the results highlight the substantial promise of the bilayer HfO2/ ZrO2 device for potential applications in non-volatile storage.