Influence of Different Electrode Materials on Bipolar Switching Characteristics for Neodymium Oxide Films Resistance Random Access Memory Devices

The present study observed and discussed the bipolar resistance switching behavior and electrical conduction transport properties of the neodymium oxide films resistive random access memory (RRAM) devices for the different thickness top electrode materials. Especially in ITO (Indium tin oxide) electrode materials, the conduction mechanism of neodymium oxide films RRAM devices for ITO electrode exhibits ohmic conduction behavior with 1 mA and 10 mA compliance currents in the set state for low operating voltages and low/high resistance values. In addition, at elevated operating voltages, the conduction mechanism displays hopping conduction behavior with 1 mA and 10 mA compliance currents. The observed increase in reset voltage indicates that oxygen ions have diffused into the vicinity of the ITO electrode during the set operation. Three hypothetical physical models are proposed, based on the relationship between different ITO electrode thicknesses and the oxygen concentration distribution effect. In conclusion, the neodymium oxide films RRAM devices exhibited high memory window properties, exemplary bipolar resistance switching characteristics, and non-volatile properties, rendering them suitable for incorporation into next-generation non-volatile memory applications.