title: Imaging interfacial electrical transport in graphene-MoS2heterostructures with electron-beam-induced-currents.
abstract: Heterostructure devices with specific and extraordinary properties can be fabricated by stacking two-dimensional crystals. Cleanliness at the inter-crystal interfaces within a heterostructure is crucial for maximizing device performance. However, because these interfaces are buried, characterizing their impact on device function is challenging. Here, we show that electron-beam induced current (EBIC) mapping can be used to image interfacial contamination and to characterize the quality of buried heterostructure interfaces with nanometer-scale spatial resolution. We applied EBIC and photocurrent imaging to map photo-sensitive graphene-MoS2heterostructures. The EBIC maps, together with concurrently acquired scanning transmission electron microscopy images, reveal how a device's photocurrent collection efficiency is adversely affected by nanoscale debris invisible to optical-resolution photocurrent mapping.
authors.affiliation: Department of Physics and Astronomy and California NanoSystems Institute, University of California , Los Angeles, California 90095, USA.
authors.forename: E R
authors.initials: ER
authors.lastname: White
authors.affiliation: Department of Physics and Astronomy and California NanoSystems Institute, University of California , Los Angeles, California 90095, USA.
authors.forename: Alexander
authors.initials: A
authors.lastname: Kerelsky
authors.affiliation: Department of Physics and Astronomy and California NanoSystems Institute, University of California , Los Angeles, California 90095, USA.
authors.forename: William A
authors.initials: WA
authors.lastname: Hubbard
authors.affiliation: Department of Electrical Engineering, University of Southern California , Los Angeles, California 90089, USA.
authors.forename: Rohan
authors.initials: R
authors.lastname: Dhall
authors.affiliation: Department of Electrical Engineering, University of Southern California , Los Angeles, California 90089, USA.
authors.forename: Stephen B
authors.initials: SB
authors.lastname: Cronin
authors.affiliation: Center for Electron Microscopy and Microanalysis, University of Southern California , Los Angeles, California 90089, USA.
authors.forename: Matthew
authors.initials: M
authors.lastname: Mecklenburg
authors.affiliation: Department of Physics and Astronomy and California NanoSystems Institute, University of California , Los Angeles, California 90095, USA.
authors.forename: B C
authors.initials: BC
authors.lastname: Regan