title: Facile graphene n-doping by wet chemical treatment for electronic applications.
abstract: We report a post-synthetic n-doping method for chemical-vapor-deposition (CVD) grown graphene using wet chemical processing. An ammonium fluoride solution was found effective in converting pristine hole doping into electron doping in addition to the mobility improvement of charge carriers. We verified the doping by electrical measurements, Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) analyses and suggest that the mechanism of n-doping is electrostatic doping by ionic physisorption of ammonium ions on the graphene surface. This simple chemical doping method provides a facile and robust route to n-doping of large area graphene for the realization of high performance graphene-based electronic devices.
authors.affiliation: Department of Electrical Engineering, KAIST, Daejeon 305-701, Republic of Korea. bjcho@kaist.edu.
authors.forename: Jae Hoon
authors.initials: JH
authors.lastname: Bong
authors.forename: Onejae
authors.initials: O
authors.lastname: Sul
authors.forename: Alexander
authors.initials: A
authors.lastname: Yoon
authors.forename: Sung-Yool
authors.initials: SY
authors.lastname: Choi
authors.forename: Byung Jin
authors.initials: BJ
authors.lastname: Cho