Electron-beam-irradiated rhenium disulfide memristors with low variability for neuromorphic computing

State-of-the-art memristors are mostly formed by vertical metal-insulator-metal (MIM) structures that rely on the formation of conductive filaments for resistive switching (RS). However, due to the stochastic formation of filaments, the set/reset voltage of vertical MIM memristors is difficult to control, resulting in poor temporal and spatial switching uniformity. Here, a two-terminal lateral memristor based on electron-beam-irradiated rhenium disulfide (ReS2) is realized, unveiling a resistive switching mechanism based on Schottky barrier height (SBH) modulation. The devices exhibit forming-free, stable gradual RS and simultaneously achieve small transition voltage variation during positive and negative sweeps (6.3%/5.3%). The RS is attributed to the motion of sulfur vacancies induced by voltage bias, which modulates the ReS2/metal SBH. The gradual SBH modulation stabilizes temporal variation in contrast to the abrupt RS in MIM-based memristors. Moreover, the emulation of long-term synaptic plasticity of biological synapses is demonstrated, manifesting potential as artificial synapses for energy-efficient neuromorphic computing.

Sifan Li, Bochang Li, Xuewei Feng, Li Chen, Yesheng Li, Li Huang, Xuanyao Fong, Kah-Wee Ang