title: Versatile sputtering technology for Al2O3gate insulators on graphene.
abstract: We report a novel, sputtering-based fabrication method of Al2O3gate insulators on graphene. Electrical performance of dual-gated mono- and bilayer exfoliated graphene devices is presented. Sputtered Al2O3layers possess comparable quality to oxides obtained by atomic layer deposition with respect to a high relative dielectric constant of about 8, as well as low-hysteresis performance and high breakdown voltage. We observe a moderate carrier mobility of about 1000 cm2V-1s-1in monolayer graphene and 350 cm2V-1s-1in bilayer graphene, respectively. The mobility decrease can be attributed to the resonant scattering on atomic-scale defects, likely originating from the Al precursor layer evaporated prior to sputtering.
authors.affiliation: Physikalisch-Technische Bundesanstalt, Bundesallee 100, D-38116, Braunschweig, Germany.
authors.forename: Miriam
authors.initials: M
authors.lastname: Friedemann
authors.affiliation: Physikalisch-Technische Bundesanstalt, Bundesallee 100, D-38116, Braunschweig, Germany.
authors.forename: Mirosław
authors.initials: M
authors.lastname: Woszczyna
authors.affiliation: Physikalisch-Technische Bundesanstalt, Bundesallee 100, D-38116, Braunschweig, Germany.
authors.forename: André
authors.initials: A
authors.lastname: Müller
authors.affiliation: Physikalisch-Technische Bundesanstalt, Bundesallee 100, D-38116, Braunschweig, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Wundrack
authors.affiliation: Physikalisch-Technische Bundesanstalt, Bundesallee 100, D-38116, Braunschweig, Germany.
authors.forename: Thorsten
authors.initials: T
authors.lastname: Dziomba
authors.affiliation: Physikalisch-Technische Bundesanstalt, Bundesallee 100, D-38116, Braunschweig, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Weimann
authors.affiliation: Physikalisch-Technische Bundesanstalt, Bundesallee 100, D-38116, Braunschweig, Germany.
authors.forename: Franz J
authors.initials: FJ
authors.lastname: Ahlers
keywords: Atomic layer deposition; Graphene; High-κ dielectric; Sputtering