Self-Rectifying Resistive Switching Memory Based on Molybdenum Disulfide for Reduction of Leakage Current in Synapse Arrays

Resistive random-access memory has emerged as a promising non-volatile memory technology, receiving substantial attention due to its potential for high operational performance, low power consumption, temperature robustness, and scalability. Two-dimensional nanostructured materials play a pivotal role in RRAM devices, offering enhanced electrical properties and physical attributes, which contribute to overall device improvement. In this study, the self-rectifying switching behavior in RRAM devices is analyzed based on molybdenum disulfide nanocomposites decorated with Pd on SiO₂/Si substrates. The switching layer integration of Pd and MoS₂ at the nanoscale effectively mitigates leakage currents decreasing from cross-talk in the RRAM array, eliminating the need for a separate selector device. The successful demonstration of the expected RRAM switching operation and low switching dispersion follows the application of a Pd nanoparticle embedding method. The switching channel layer is presented as an independent (Pd nanoparticle coating and MoS₂ nanosheet) nanocomposite. The switching layer length (4000 μm) and width (7000 μm) play an important role in a lateral-conductive-filament-based RRAM device. Through the bipolar switching behavior extraction of RRAM, the formation of the conductive bridges via electronic migration is explained. The fabricated Pd-MoS₂ synaptic RRAM device results in a high resistive current ratio for a forward/reverse current higher than 60 at a low resistance state and observes a memory on/off ratio of 10³, exhibiting stable resistance switching behavior.