title: Planar edge Schottky barrier-tunneling transistors using epitaxial graphene/SiC junctions.
abstract: A purely planar graphene/SiC field effect transistor is presented here. The horizontal current flow over one-dimensional tunneling barrier between planar graphene contact and coplanar two-dimensional SiC channel exhibits superior on/off ratio compared to conventional transistors employing vertical electron transport. Multilayer epitaxial graphene (MEG) grown on SiC(0001̅) was adopted as the transistor source and drain. The channel is formed by the accumulation layer at the interface of semi-insulating SiC and a surface silicate that forms after high vacuum high temperature annealing. Electronic bands between the graphene edge and SiC accumulation layer form a thin Schottky barrier, which is dominated by tunneling at low temperatures. A thermionic emission prevails over tunneling at high temperatures. We show that neglecting tunneling effectively causes the temperature dependence of the Schottky barrier height. The channel can support current densities up to 35 A/m.
authors.affiliation: School of Physics, Georgia Institute of Technology , Atlanta, Georgia 30332, United States.
authors.forename: Jan
authors.initials: J
authors.lastname: Kunc
authors.forename: Yike
authors.initials: Y
authors.lastname: Hu
authors.forename: James
authors.initials: J
authors.lastname: Palmer
authors.forename: Zelei
authors.initials: Z
authors.lastname: Guo
authors.forename: John
authors.initials: J
authors.lastname: Hankinson
authors.forename: Salah H
authors.initials: SH
authors.lastname: Gamal
authors.forename: Claire
authors.initials: C
authors.lastname: Berger
authors.forename: Walt A
authors.initials: WA
authors.lastname: de Heer
keywords: Epitaxial graphene; Schottky barrier transistor; semi-insulating silicon carbide; space-charge-limited current; tunneling field effect transistor