title: Field-effect modulation of thermoelectric properties in multigated silicon nanowires.
abstract: Electric-field-induced charge carriers typically exhibit greater mobility over carriers contributed by chemical dopants and offer a powerful mechanism for thermoelectric power factor enhancement. We fabricate multigated silicon nanowires (Si NWs) and demonstrate significant modulation of electrical conductivity and the Seebeck coefficient with gate bias. Because of the higher mobility of field-effect charge carriers, we demonstrate that power factor for the gated Si NWs is similar to the highest values reported for n-type Si nanostructures despite charge transport only occurring at the NW surface. Field-effect doping is a promising strategy for optimizing power factor and may result in significant power factor enhancement in smaller diameter Si NWs where high average carrier densities can be obtained with induced surface charge.
authors.affiliation: Department of Electrical and Computer Engineering and ‡Materials Department, University of California , Santa Barbara, California 93106, United States.
authors.forename: Benjamin M
authors.initials: BM
authors.lastname: Curtin
authors.forename: Emilio A
authors.initials: EA
authors.lastname: Codecido
authors.forename: Stephan
authors.initials: S
authors.lastname: Krämer
authors.forename: John E
authors.initials: JE
authors.lastname: Bowers
mesh_terms: D004553:Electric Conductivity; D005857:Germanium / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry; D036103:Nanotechnology; D053770:Nanowires / Q000737:chemistry*; D010316:Particle Size; D012825:Silicon / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D005857:Germanium; D012825:Silicon