In situ vulcanization synthesis of CuInS2 nanosheet arrays for a memristor with a high on–off ratio and low power consumption

Abstract

Copper chalcogenides-based memristors have provided an attractive option for constructing high performance nonvolatile memory storage devices. However, the presence of lateral leakage inside the film-based switching media impedes the effective integration and uniformity of multiple memory cells. Herein, we report a ternary compound CuInS₂ as the resistive switching material for memory devices with unique structure of vertical nanosheet arrays fabricated by a low temperature solution method. The device exhibits obvious bipolar resistive switching performance with a high R_OFF/R_ON ratio of ∼10⁶ and a low power consumption of ∼100 pW. Besides, the vertical network frame structure of CuInS₂ nanosheet arrays could effectively limit the random electrical leakage paths and substantially improve the stability, which can achieve an excellent data retention time over 10⁴ s. Furthermore, we have demonstrated that the Pool–Frenkel emission and ions migration are responsible for the memristive switching mechanism. These results reveal that the copper indium sulfide nanosheets with excellent performance will be a potential candidate for large-scale, energy-efficient future integrated electronic systems.