title: Uniform Self-rectifying Resistive Switching Behavior via Preformed Conducting Paths in a Vertical-type Ta2O5/HfO2-x Structure with a Sub-μm(2) Cell Area.
abstract: To replace or succeed the present NAND flash memory, resistive switching random access memory (ReRAM) should be implemented in the vertical-type crossbar array configuration. The ReRAM cell must have a highly reproducible resistive switching (RS) performance and an electroforming-free, self-rectifying, low-power-consumption, multilevel-switching, and easy fabrication process with a deep sub-μm(2) cell area. In this work, a Pt/Ta2O5/HfO2-x/TiN RS memory cell fabricated in the form of a vertical-type structure was presented as a feasible contender to meet the above requirements. While the fundamental RS characteristics of this material based on the electron trapping/detrapping mechanisms have been reported elsewhere, the influence of the cell scaling size to 0.34 μm(2) on the RS performance by adopting the vertical integration scheme was carefully examined in this work. The smaller cell area provided much better switching uniformity while all the other benefits of this specific material system were preserved. Using the overstressing technique, the nature of RS through the localized conducting path was further examined, which elucidated the fundamental difference between the present material system and the general ionic-motion-related bipolar RS mechanism.
authors.affiliation: Department of Materials Science and Engineering and Inter-University Semiconductor Research Center, Seoul National University , Seoul 151-744, Republic of Korea.
authors.forename: Jung Ho
authors.initials: JH
authors.lastname: Yoon
authors.affiliation: Department of Materials Science and Engineering and Inter-University Semiconductor Research Center, Seoul National University , Seoul 151-744, Republic of Korea.
authors.forename: Sijung
authors.initials: S
authors.lastname: Yoo
authors.affiliation: Department of Materials Science and Engineering and Inter-University Semiconductor Research Center, Seoul National University , Seoul 151-744, Republic of Korea.
authors.forename: Seul Ji
authors.initials: SJ
authors.lastname: Song
authors.affiliation: Department of Materials Science and Engineering and Inter-University Semiconductor Research Center, Seoul National University , Seoul 151-744, Republic of Korea.
authors.forename: Kyung Jean
authors.initials: KJ
authors.lastname: Yoon
authors.affiliation: Department of Materials Science and Engineering and Inter-University Semiconductor Research Center, Seoul National University , Seoul 151-744, Republic of Korea.
authors.forename: Dae Eun
authors.initials: DE
authors.lastname: Kwon
authors.affiliation: Department of Materials Science and Engineering and Inter-University Semiconductor Research Center, Seoul National University , Seoul 151-744, Republic of Korea.
authors.forename: Young Jae
authors.initials: YJ
authors.lastname: Kwon
authors.affiliation: Department of Materials Science and Engineering and Inter-University Semiconductor Research Center, Seoul National University , Seoul 151-744, Republic of Korea.
authors.forename: Tae Hyung
authors.initials: TH
authors.lastname: Park
authors.affiliation: Department of Materials Science and Engineering and Inter-University Semiconductor Research Center, Seoul National University , Seoul 151-744, Republic of Korea.
authors.forename: Hye Jin
authors.initials: HJ
authors.lastname: Kim
authors.affiliation: Department of Materials Science and Engineering and Inter-University Semiconductor Research Center, Seoul National University , Seoul 151-744, Republic of Korea.
authors.forename: Xing Long
authors.initials: XL
authors.lastname: Shao
authors.affiliation: Department of Materials Science and Engineering and Inter-University Semiconductor Research Center, Seoul National University , Seoul 151-744, Republic of Korea.
authors.forename: Yumin
authors.initials: Y
authors.lastname: Kim
authors.affiliation: Department of Materials Science and Engineering and Inter-University Semiconductor Research Center, Seoul National University , Seoul 151-744, Republic of Korea.
authors.forename: Cheol Seong
authors.initials: CS
authors.lastname: Hwang
keywords: electroforming-free; low power consumption; resistive random access memory; self-rectification; uniform switching; vertical integration structure