journal article·2020-05-12Open access

Tuning transport across MoS2/graphene interfaces via as-grown lateral heterostructures

Shruti Subramanian, Ke Xu, Yuanxi Wang, Simon Moser, Nicholas A. Simonson, Donna Deng, Vincent H. Crespi, Susan K. Fullerton-Shirey, Joshua A. Robinson

Abstract

Abstract An unexploited property of graphene-based heterojunctions is the tunable doping of the junction via electrostatic gating. This unique property may be key in advancing electronic transport across interfaces with semiconductors. Here, we engineer transport in semiconducting TMDs by constructing a lateral heterostructure with epitaxial graphene and tuning its intrinsic doping to form a p–n junction between the graphene and the semiconducting TMDs. Graphene grown on SiC (epitaxial graphene) is intrinsically doped via substrate polarization without the introduction of an external dopant, thus enabling a platform for pristine heterostructures with a target band alignment. We demonstrate an electrostatically tunable graphene/MoS2p–n junction with >20× reduction and >10× increased tunability in contact resistance (Rc) compared with metal/TMD junctions, attributed to band alignment engineering and the tunable density of states in graphene. This unique concept provides improved control over transport across 2D p–n junctions.
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Research context

OpenAlex topics: Graphene research and applications · 2D Materials and Applications · Quantum and electron transport phenomena

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