Modulation of Schottky barrier height in graphene/MoS2/metal vertical heterostructure with large current ON–OFF ratio

Detail transport properties of graphene/MoS 2 /metal vertical heterostructure have been investigated. The van der Waals interface between the graphene and MoS 2 exhibits Schottky barrier. The application of gate voltage to the graphene layer enables us to modulate the Schottky barrier height; thus gives rise to the control of the current flow across the interface. By analyzing the temperature dependence of the conductance, the modulation of Schottky barrier height Δφ has been directly determined. We observed significant MoS 2 layer number dependence of Δφ. Moreover, we demonstrate that the device which shows larger Δφ exhibits larger current modulation; this is consistent with the fact that the transport of these devices is dominated by graphene/MoS 2 Schottky barrier.