Effect of graphene intercalation on nonlinearity of Ag/quartz/Pt selector: first-principle calculations

In this work, Ag/graphene(GR)/quartz/Pt and Ag/quartz/Pt selectors were investigated using first-principle calculations. Comparison of the electrostatic potential distribution, plane-averaged electron density difference, and density of states (DOS) of the Ag(111)/quartz(001) and Ag(111)/GR/quartz(001) interfaces shows that the insertion of GR increases the interfacial Schottky barrier height (SBH), decreases the interfacial charge transfer, and improves the conductivity and reliability of quartz. Ag/GR/quartz/Pt and Ag/quartz/Pt selectors are then designed using the above interfaces. Results show that the OFF-state current of the Ag/GR/quartz/Pt selector is reduced by about one order of magnitude, Idrive is improved (especially the positive drive current), and its nonlinearity (NL) is significantly increased. Thus, the Ag/GR/quartz/Pt selectors can better suppress leakage current in one-Selector one-RRAM (1S1R) cross array than the Ag/quartz/Pt selectors. This work may be instructive and valuable for the design and optimization of Ag/quartz/Pt selectors.