Electrical Properties and Fatigue Behaviors of ZrO2 Resistive Switching Thin Films

The resistive switching mechanisms of ZrO 2 memory films are proposed to explain why resistive switching characteristics of Ti/ZrO 2 /Pt device are more stable than those of Pt/ZrO 2 /Pt and Al/ZrO 2 /Pt devices in this study. Different from the Pt/ZrO 2 /Pt and the Al/ZrO 2 /Pt devices, the carrier conduction mechanisms in the Ti/ZrO 2 /Pt device obey space charge limited current theory, which may be caused by the formation of the interface layer between Ti and ZrO 2 . Moreover, the resistive switching mechanisms are proposed to be related to the filament formation/rupture theory and oxygen ion migration. The location where filament formation/rupture takes place should be confined near the interface between Ti and ZrO 2 , leading to the stable resistive switching characteristics and a better endurance performance. During successive resistive cycles at room temperature and 150°C, the fatigue behaviors are observed due to the degradation of both two memory states, which might be related to the transformation of the interface layers between Ti and ZrO 2 and the coalescence of ZrO x clusters.