title: Chemical doping of MoS2multilayer by p-toluene sulfonic acid.
abstract: We report the tailoring of the electrical properties of mechanically exfoliated multilayer (ML) molybdenum disulfide (MoS2) by chemical doping. Electrical charge transport and Raman spectroscopy measurements revealed that the p-toluene sulfonic acid (PTSA) imposes n-doping in ML MoS2. The shift of threshold voltage for ML MoS2transistor was analyzed as a function of reaction time. The threshold voltage shifted toward more negative gate voltages with increasing reaction time, which indicates an n-type doping effect. The shift of the Raman peak positions was also analyzed as a function of reaction time. PTSA treatment improved the field-effect mobility by a factor of ~4 without degrading the electrical characteristics of MoS2devices.
authors.affiliation: Department of Physics and Graphene Research Institute, Sejong University, Seoul 143-747, Korea.
authors.forename: Shaista
authors.initials: S
authors.lastname: Andleeb
authors.affiliation: Department of Physics and Graphene Research Institute, Sejong University, Seoul 143-747, Korea; Department of Physics, Motilal Nehru National Institute of Technology, Allahabad-211004, India.
authors.forename: Arun
authors.initials: A
authors.lastname: Kumar Singh
authors.affiliation: Department of Physics and Graphene Research Institute, Sejong University, Seoul 143-747, Korea.
authors.forename: Jonghwa
authors.initials: J
authors.lastname: Eom
keywords: doping; field-effect transistor; molybdenum disulfide; p-toluene sulfonic acid