Evidences of Electrode-Controlled Retention Properties in Ta2O5-Based Resistive-Switching Memory Cells

Abstract

In this letter we optimize Ta2O5-based resistive-switching memory cells for improved retention properties. We show that the electrode material used as oxygen-scavenging element directly controls the state stability. As compared to TiN\Ta2O5\Ti cells the conductive filament retention is improved for TiN\Ta2O5\Ta cells due to the lower oxygen affinity of Ta. The oxygen chemical potential profile along the filament is also modulated by the Ta thickness, allowing reaching excellent retention of both low- and high-resistance states for several weeks at 250°C.