title: Use of phosphine as an n-type dopant source for vapor-liquid-solid growth of silicon nanowires.
abstract: Phosphine (PH3) was investigated as an n-type dopant source for Au-catalyzed vapor-liquid-solid (VLS) growth of phosphorus-doped silicon nanowires (SiNWs). Transmission electron microscopy characterization revealed that the as-grown SiNWs were predominately single crystal even at high phosphorus concentrations. Four-point resistance and gate-dependent conductance measurements confirmed that electrically active phosphorus was incorporated into the SiNWs during VLS growth. A transition was observed from p-type conduction for nominally undoped SiNWs to n-type conduction upon the introduction of PH3 to the inlet gas. The resistivity of the n-type SiNWs decreased by approximately 3 orders of magnitude as the inlet PH3 to silane (SiH4) gas ratio was increased from 2 x 10(-5) to 2 x 10(-3). These results demonstrate that PH3 can be used to produce n-type SiNWs with properties that are suitable for electronic and optoelectronic device applications.
authors.affiliation: Department of Electrical Engineering, Pennsylvania State University, University Park, Pennsylvania 16802, USA.
authors.forename: Yanfeng
authors.initials: Y
authors.lastname: Wang
authors.forename: Kok-Keong
authors.initials: KK
authors.lastname: Lew
authors.forename: Tsung-Ta
authors.initials: TT
authors.lastname: Ho
authors.forename: Ling
authors.initials: L
authors.lastname: Pan
authors.forename: Steven W
authors.initials: SW
authors.lastname: Novak
authors.forename: Elizabeth C
authors.initials: EC
authors.lastname: Dickey
authors.forename: Joan M
authors.initials: JM
authors.lastname: Redwing
authors.forename: Theresa S
authors.initials: TS
authors.lastname: Mayer