title: Modification of electronic properties of top-gated graphene devices by ultrathin yttrium-oxide dielectric layers.
abstract: We report the structure characterization and electronic property modification of single layer graphene (SLG) field-effect transistor (FET) devices top-gated using ultrathin Y(2)O(3) as dielectric layers. Based on the Boltzmann transport theory within variant screening, Coulomb scattering is confirmed quantitatively to be dominant in Y(2)O(3)-covered SLG and a very few short-range impurities have been introduced by Y(2)O(3). Both DC transport and AC capacitance measurements carried out at cryogenic temperatures demonstrate that the broadening of Landau levels is mainly due to the additional charged impurities and inhomogeneity of carriers induced by Y(2)O(3) layers.
authors.affiliation: Department of Physics and the William Mong Institute of Nano Science and Technology, Hong Kong University of Science and Technology, Hong Kong, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Wang
authors.forename: Xiaolong
authors.initials: X
authors.lastname: Chen
authors.forename: Yang
authors.initials: Y
authors.lastname: Wang
authors.forename: Zefei
authors.initials: Z
authors.lastname: Wu
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.forename: Yu
authors.initials: Y
authors.lastname: Han
authors.forename: Mingwei
authors.initials: M
authors.lastname: Zhang
authors.forename: Yuheng
authors.initials: Y
authors.lastname: He
authors.forename: Chao
authors.initials: C
authors.lastname: Zhu
authors.forename: Kwok Kwong
authors.initials: KK
authors.lastname: Fung
authors.forename: Ning
authors.initials: N
authors.lastname: Wang
mesh_terms: D003217:Conductometry / Q000295:instrumentation*; D004553:Electric Conductivity; D004574:Electromagnetic Fields; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006108:Graphite / Q000737:chemistry*; D008422:Materials Testing; D008567:Membranes, Artificial; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D015019:Yttrium / Q000737:chemistry*
chemical_list: D008567:Membranes, Artificial; D015019:Yttrium; D006108:Graphite; C091417:yttria