Charge transmission of MoS2/MoTe2 vertical heterojunction and it's modulation

Abstract

Two-dimensional material heterojunction device with unique photoelectric properties due to its nanoscale thickness and van der Waals contact surface. In this paper, a MoS2/MoTe2 vertical vdWs heterojunction device with Gate-tunable is constructed. The Kelvin probe force microscopy (KPFM) technology is combined with the electric transport measurement technology, which reveals the charge transport behavior of the MoS2/MoTe2 heterojunction under dark and light conditions, including the bipolarity characteristics of the transition from n-n+ junction to p-n junction. This paper comprehensively and systematically explains the charge transport mechanism of heterojunction, including the charge transmission process of n-n+ junction and p-n junction under positive and negative bias conditions, the transformation of nodule behavior with gate voltage, the influence of barriers on charge transmission, the different rectification characteristics between n-n+ junction and p-n junction, the major role of source and leakage bias voltage on band tunneling, and the influence of photogenerated carriers on electrical transmission. The method in this paper can be generalized to other two-dimensional heterojunction systems and provides an important reference and reference for improving the performance of two-dimensional semiconductor devices and their applications in the future.