Resistive switching mechanism of MoS 2 based atomristor.

The non-volatile resistive switching process of a MoS 2 based atomristor with a vertical structure is investigated by first-principles calculations. It is found that the monolayer MoS 2 with 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 MoS 2 monolayer, 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 MoS 2 viaVSis 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 MoS 2 based atomristor. The investigation here promotes the atomic level understanding of the resistive switching properties about the monolayer MoS 2 based memristor. The physics behind should also work in atomristors based on other monolayer transition-metal dichalcogenides, like WSe 2 and MoTe 2 . The investigation will be a reference for atomristor-device design or optimization.