Resistive Switching Characteristics of Tm $_{2}$ O $_{3}$ , Yb

In this paper, we investigated the electroforming-free resistive switching (RS) behavior in the Ru/RE₂O₃/TaN (rare-earth, RE, RE = Tm, Yb, and Lu) memory device fabricated with full room temperature process. The conduction mechanism of RE₂O₃-based memory devices in the low-resistance state is ohmic emission, whereas Tm₂O₃, Yb₂O₃, and Lu₂O₃ memory devices in the high-resistance state are space charge limited conduction (SCLC), ohmic behavior, and SCLC, respectively. The Ru/Lu₂O₃/TaN device showed a high-resistance ratio of ~ 10⁴, a high device yield of ~70%, a good data retention as long as 10⁵s measured at 85°C, and a reliable endurance for up to 100 cycles, suggesting the optimal chemical defects (metallic Lu and nonlattice oxygen ion) in Lu₂O₃ film. All of these results suggest that Ru/Lu₂O₃/TaN structure memory is a good candidate for future nonvolatile RS memory applications.