Use of phosphine as an n-type dopant source for vapor-liquid-solid growth of silicon nanowires.
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.
Wang
Yanfeng
Y
Department of Electrical Engineering, Pennsylvania State University, University Park, Pennsylvania 16802, USA.
Lew
Kok-Keong
KK
Ho
Tsung-Ta
TT
Pan
Ling
L
Novak
Steven W
SW
Dickey
Elizabeth C
EC
Redwing
Joan M
JM
Mayer
Theresa S
TS