Effect of chemical bonding states in TaOx base layers on rectifying bipolar resistive switching characteristics

Abstract

In this study, the authors investigated the rectifying bipolar resistive switching characteristics of Pt/HfO2/TaOx/Pt heterostacks with respect to the chemical bonding states of the TaOx base layer and the physical properties of the insulator layer. The authors demonstrated that the migration of oxygen ions at the interface between the HfO2 insulator layer and the TaOx base layer produced the rectifying bipolar resistive switching, and the switching current could be controlled via the oxygen concentration in the TaOx layer. They also observed that the current at the high-resistance state decreased with increasing thickness of the HfO2 insulator layer. Rectifying bipolar resistive switching behavior was additionally demonstrated by using an Al2O3 layer as an insulator instead of HfO2.

An Investigation on Resistive Switching Characteristics Induced by HfO_xand Electrode Interfaces

“…To induce dissolution and formation of filaments at the interface between the electrode and matrix, an asymmetrical structure (different metals as top and bottom electrodes) was proposed [10,24].In addition, there was a report on controlling the rupture and recovery of filaments at the interface between layers for a multilayer-electrolyte [25]. However, few reported a symmetrical structure (the same metal as a top and bottom electrode) for their investigation of unipolar and bipolar RS and as a comparison of the two interfaces serving as the active switching region.…”