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

摘要

Detail transport properties of graphene/MoS2/metal vertical heterostructurehave been investigated. The van der Waals interface between the graphene andMoS2 exhibits Schottky barrier. The application of gate voltage to the graphenelayer enables us to modulate the Schottky barrier height; thus gives rise tothe control of the current flow across the interface. By analyzing thetemperature dependence of the conductance, the modulation of Schottky barrierheight {\Delta}{\phi} has been directly determined. We observed significantMoS2 layer number dependence of {\Delta}{\phi}. Moreover, we demonstrate thatthe device which shows larger {\Delta}{\phi} exhibits larger currentmodulation; this is consistent with the fact that the transport of thesedevices is dominated by graphene/MoS2 Schottky barrier.