title: Nanoscale lithography on monolayer graphene using hydrogenation and oxidation.
abstract: Monolayer graphene is one of the most interesting materials applicable to next-generation electronic devices due to its transport properties. However, realization of graphene devices requires suitable nanoscale lithography as well as a method to open a band gap in monolayer graphene. Nanoscale hydrogenation and oxidation are promising methods to open an energy band gap by modification of surface structures and to fabricate nanostructures such as graphene nanoribbons (GNRs). Until now it has been difficult to fabricate nanoscale devices consisting of both hydrogenated and oxidized graphene because the hydrogenation of graphene requires a complicated process composed of large-scale chemical modification, nanoscale patterning, and etching. We report on nanoscale hydrogenation and oxidation of graphene under normal atmospheric conditions and at room temperature without etching, wet process, or even any gas treatment by controlling just an external bias through atomic force microscope lithography. Both the lithographically defined nanoscale hydrogenation and oxidation have been confirmed by micro-Raman spectroscopy measurements. Patterned hydrogenated and oxidized graphene show insulating behaviors, and their friction values are several times larger than those of graphene. These differences can be used for fabricating electronic or electromechanical devices based on graphene.
authors.affiliation: Division of Quantum Phases & Devices, Department of Physics, Konkuk University, Seoul 143-701, Korea.
authors.forename: Ik-Su
authors.initials: IS
authors.lastname: Byun
authors.forename: Duhee
authors.initials: D
authors.lastname: Yoon
authors.forename: Jin Sik
authors.initials: JS
authors.lastname: Choi
authors.forename: Inrok
authors.initials: I
authors.lastname: Hwang
authors.forename: Duk Hyun
authors.initials: DH
authors.lastname: Lee
authors.forename: Mi Jung
authors.initials: MJ
authors.lastname: Lee
authors.forename: Tomoji
authors.initials: T
authors.lastname: Kawai
authors.forename: Young-Woo
authors.initials: YW
authors.lastname: Son
authors.forename: Quanxi
authors.initials: Q
authors.lastname: Jia
authors.forename: Hyeonsik
authors.initials: H
authors.lastname: Cheong
authors.forename: Bae Ho
authors.initials: BH
authors.lastname: Park