Dynamic conductance characteristics in HfOx-based resistive random access memory

Abstract

Characteristics of HfO_x-based resistive switching memory (RRAM) in Al/HfO_x/Al and Al/AlO_x/HfO_x/Al structures were studied using a dynamic conductance method. Step-like RESET behaviors as well as pre- and post-RESET regions of operation were characterized. The results indicated that defects at the oxide interface caused cycling issues in the Al/AlO_x/HfO_x/Al structure. No such RESET behavior was observed for the Al/HfO_x/Al structure. Current induced over-heating, which caused an early RESET event, could be avoided using current-sweep technique that caused less electrical and thermal stress in localized regions. The experimental results not only provided insights into potential reliability issues and power management in HfO_x-based RRAM, but also helped clarifying the resistive switching mechanisms.