Synthesis and electrical characteristics of graphene-MoS2-graphene lateral heterostructure

Abstract

With outstanding electronic and optical properties, molybdenum disulfide (MoS₂) has become one of the potential materials for logic applications and photodetector. However, Schottky barrier formation based on metal-MoS₂ contacts has limited device performance. Recently, many attempts have been devoted to addressing this challenge by using low-work function metal electrodes, high-temperature annealing, or phase engineering. Graphene is known as an ideal electrode for the interconnections and wiring of next-generation devices due to its superior electrical conductivity and ease of tuning its Fermi level. In this study, we successfully fabricated graphene-MoS₂ lateral heterostructure by the chemical vapour deposition (CVD) technique under atmospheric pressure, in which, the edges of the graphene template served as nucleation sites for the growth of MoS₂. The morphology of the heterojunction was confirmed by optical microscopy and atomic force microscopy. Raman and Raman mapping were used to estimate the quality and uniformity of the heterojunction. The device fabricated on the graphene-MoS₂ heterojunction exhibits n-type semiconductor transport characteristics, with MoS₂ serving as the conducting channel while graphene acts as the electrode. Additionally, the output characterisation showed that there is a formation of an ohmic contact between graphene and MoS₂.