Abstract
Tungsten oxide (WO X ) resistive memory (ReRAM), a two-terminal CMOS compatible nonvolatile memory, has shown promise to surpass the existing flash memory in terms of scalability, switching speed, and potential for 3D stacking. The memory layer, WO X , can be easily fabricated by down-stream plasma oxidation (DSPO) or rapid thermal oxidation (RTO) of W plugs universally used in CMOS circuits. Results of conductive AFM (C-AFM) experiment suggest the switching mechanism is dominated by the REDOX (Reduction-oxidation) reaction—the creation of conducting filaments leads to a low resistance state and the rupturing of the filaments results in a high resistance state. Our experimental results show that the reactions happen at the TE/WO X interface. With this understanding in mind, we proposed two approaches to boost the memory performance: (i) using DSPO to treat the RTO WO X surface and (ii) using Pt TE, which forms a Schottky barrier with WO X . Both approaches, especially the latter, significantly reduce the forming current and enlarge the memory window.
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Chien, W.C., Chen, Y.C., Lai, E.K. et al. A study of the switching mechanism and electrode material of fully CMOS compatible tungsten oxide ReRAM. Appl. Phys. A 102, 901–907 (2011). https://doi.org/10.1007/s00339-011-6271-x
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DOI: https://doi.org/10.1007/s00339-011-6271-x