Cover Picture: Memristive switching behavior in Pr0.7Ca0.3MnO3 by incorporating an oxygen-deficient layer (Phys. Status Solidi RRL 10–11/2011)
Sangsu Park, Seungjae Jung, Manzar Siddik, Minseok Jo, Joonmyoung Lee, Jubong Park, Wootae Lee, Seonghyun Kim, Sharif Md. Sadaf, Xinjun Liu and Hyunsang Hwang
Article first published online: 24 OCT 2011 | DOI: 10.1002/pssr.201190023
For resistive random-access memory (RRAM) devices based on Pr0.7Ca0.3MnO3 (PCMO), reliable memristive switching properties have been achieved by replacing the conventional reactive metal electrode with an oxygen-deficient PCMO3–x layer. Based on electrical characterization results and X-ray photo- electron spectroscopy analysis, Sangsu Park et al. (pp. 409–411) discuss the role of the PCMO3–x layer in resistive switching. When a positive bias is applied to the top electrode, oxygen ions (O2–) are attracted to the PCMO3 region; this increases the resistance of PCMO3–x, leading to a high-resistance state. Conversely, when a negative bias is applied to the top electrode, the O2– ions move back to the PCMO3–x layer, which in turn decreases the resistance of PCMO3–x, leading to a low-resistance state. Hence, the oxygen vacancy/ion migration between stoichiometric PCMO (PCMO3) and PCMO3–x causes the total resistance state of the device to change.