Resistive switching mechanism of MoS₂based atomristor

The non-volatile resistive switching process of a MoS₂based atomristor with a vertical structure is investigated by first-principles calculations. It is found that the monolayer MoS₂with a S vacancy defect (VS) could maintain an insulation characteristic and a high resistance state (HRS) is remained. As an electrode metal atom is adsorbed on the MoS₂monolayer, the semi-conductive filament is formed with the assistance ofVS. Under this condition, the atomristor presents a low resistance state (LRS). The ON state current of this semi-filament is increased close to two orders of magnitude larger than that without the filament. The energy barrier for an Au-atom to penetrate the monolayer MoS₂viaVSis as high as 6.991 eV. When it comes to a double S vacancy (VS2), the energy barrier is still amounted to 3.554 eV, which manifests the bridge-like full conductive filament cannot form in monolayer MoS₂based atomristor. The investigation here promotes the atomic level understanding of the resistive switching properties about the monolayer MoS₂based memristor. The physics behind should also work in atomristors based on other monolayer transition-metal dichalcogenides, like WSe₂and MoTe₂. The investigation will be a reference for atomristor-device design or optimization.