Wafer-Scale Fabrication of Al/MoS₂/Poly-Si Memristors and Insight of Mechanism on the Resistive Switching

Resistive switching properties in 2D materials have attracted enormous research attention. However, structures using a transfer process and noble metals are still far from practical applications. An ultrathin memristor with Al/MoS₂/poly-Si structure has been demonstrated featuring highly Si-compatible and full-wafer processes. The fabricated devices showed a high ON/OFF resistive switching (RS) ratio of 1 × 10⁴, endurance cycles greater than 1 × 10³, and retention exceeding ≥10⁴ s. Systematical electrical characterizations at various temperatures were performed to investigate the detailed RS and conduction mechanisms. The diffusion of sulfur ions/vacancies occurring between the metal electrode and the MoS₂ multilayer film accounted for the major RS properties. Trap-assisted tunneling appeared to dominate the high resistance state (HRS). For the low resistance state (LRS), Schottky emission/Ohmic-behavior dominated at low/high temperature regimes. The grain boundaries in the polycrystalline MoS₂ film and interfacial layer appeared to be the key to filament formation and annihilation as well as the transport mechanism. This work presents a promising MoS₂-based memristor structure and a comprehensive understanding of the operation mechanism, which is favorable for the next generation of memory devices in pursuit of ultrahigh density in wafer-scale.