title: Electron-hole transport and photovoltaic effect in gated MoS2 Schottky junctions.
abstract: Semiconducting molybdenum disulfphide has emerged as an attractive material for novel nanoscale optoelectronic devices due to its reduced dimensionality and large direct bandgap. Since optoelectronic devices require electron-hole generation/recombination, it is important to be able to fabricate ambipolar transistors to investigate charge transport both in the conduction band and in the valence band. Although n-type transistor operation for single-layer and few-layer MoS2 with gold source and drain contacts was recently demonstrated, transport in the valence band has been elusive for solid-state devices. Here we show that a multi-layer MoS2 channel can be hole-doped by palladium contacts, yielding MoS2 p-type transistors. When two different materials are used for the source and drain contacts, for example hole-doping Pd and electron-doping Au, the Schottky junctions formed at the MoS2 contacts produce a clear photovoltaic effect.
authors.affiliation: Department of Physics, Georgetown University, Washington, DC 20057, USA.
authors.forename: Marcio
authors.initials: M
authors.lastname: Fontana
authors.forename: Tristan
authors.initials: T
authors.lastname: Deppe
authors.forename: Anthony K
authors.initials: AK
authors.lastname: Boyd
authors.forename: Mohamed
authors.initials: M
authors.lastname: Rinzan
authors.forename: Amy Y
authors.initials: AY
authors.lastname: Liu
authors.forename: Makarand
authors.initials: M
authors.lastname: Paranjape
authors.forename: Paola
authors.initials: P
authors.lastname: Barbara