Pressure-mediated contact quality improvement between monolayer MoS2 and graphite**Project supported by the National Key R&D Program, China (Grant No. 2016YFA0300904), the Key Research Program of Frontier Sciences of the Chinese Academy of Sciences (Grant No. QYZDB-SSW-SLH004), the Strategic Priority Research Program (B) of the Chinese Academy of Sciences (Grant Nos. XDPB06 and XDB07010100), and the National Natural Science Foundation of

Abstract

Two-dimensional (2D) materials and their heterostructures have attracted a lot of attention due to their unique electronic and optical properties. MoS2 as the most typical 2D semiconductors has great application potential in thin film transistors, photodetector, hydrogen evolution reaction, memory device, etc. However, the performance of MoS2 devices is limited by the contact resistance and the improvement of its contact quality is important. In this work, we report the experimental investigation of pressure-enhanced contact quality between monolayer MoS2 and graphite by conductive atom force microscope (C-AFM). It was found that at high pressure, the contact quality between graphite and MoS2 is significantly improved. This pressure-mediated contact quality improvement between MoS2 and graphite comes from the enhanced charge transfer between MoS2 and graphite when MoS2 is stretched. Our results provide a new way to enhance the contact quality between MoS2 and graphite for further applications.