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Flexible cation-based threshold selector for resistive switching memory integration

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Emerging resistive switching random access memory (RRAM), considered as the most promising candidate of flash memory, is favorable for in flexible electronic system. However, in high density flexible crossbar RRAM array, crosstalk issue that currents from the neighboring unselected cell lead to failure of write and read operations, still keeps a main bottleneck. Therefore, flexible selector compatible with the flexibility of the RRAM array should be focused on to configure one selector-one resistor (1S1R) system, which is immune to crosstalk issue. In this paper, flexible cation-based threshold switching (TS) selectors (Pt/Ag/HfO2/Pt/Ti/parylene) are fabricated and the compressive performance is studied systematically. The device shows excellent bidirectional volatile TS characteristics, including high selectivity ratio (109), low operating voltages (|VTH|<1 V), ultra-low leakage current (~10−13 A) and good flexibility. The successful demonstration of the wire connected 1S1R unit comprising this flexible selector and one bipolar resistor cell indicates the great potential of this cation-based selector to restrain the crosstalk issue in a large flexible RRAM array.

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This work was supported by National Key R&D Program (Grant No. 2017YFB0405603), Beijing Training Project for the Leading Talents in S&T (Grant No. ljrc201508), Youth Innovation Promotion Association, Chinese Academy of Sciences (Grant No. 2015096), Opening Project of Key Laboratory of Microelectronics Devices and Integrated Technology, Institute of Microelectronics, Chinese Academy of Sciences (Grant No. Y7YS033003).

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Correspondence to Xiangheng Xiao or Qi Liu.

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Zhao, X., Wang, R., Xiao, X. et al. Flexible cation-based threshold selector for resistive switching memory integration. Sci. China Inf. Sci. 61, 060413 (2018). https://doi.org/10.1007/s11432-017-9352-0

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  • cation-based threshold switching
  • resistive switching
  • flexible selector
  • conductive filament (CF)
  • 1S1R