In Situ Heat-Induced Replacement of GaAs Nanowires by Au.
Here we report on the heat-induced solid-state replacement of GaAs by Au in nanowires. Such replacement of semiconductor nanowires by metals is envisioned as a method to achieve well-defined junctions within nanowires. To better understand the mechanisms and dynamics that govern the replacement reaction, we performed in situ heating studies using high-resolution scanning transmission electron microscopy. The dynamic evolution of the phase boundary was investigated, as well as the crystal structure and orientation of the different phases at reaction temperatures. In general, the replacement proceeds one GaAs(111) bilayer at a time, and no fixed epitaxial relation could be found between the two phases. The relative orientation of the phases affects the replacement dynamics and can induce growth twins in the Au nanowire phase. In the case of a limited Au supply, the metal phase can also become liquid.
Vidar T
VT
Fauske
Junghwan
J
Huh
Department of Materials Science and Metallurgy, University of Cambridge , Cambridge CB3 0FS, United Kingdom.
Giorgio
G
Divitini
CrayoNano AS , Otto Nielsens vei 12, NO-7052 Trondheim, Norway.
Dasa L
DL
Dheeraj
CrayoNano AS , Otto Nielsens vei 12, NO-7052 Trondheim, Norway.
A Mazid
AM
Munshi
Department of Materials Science and Metallurgy, University of Cambridge , Cambridge CB3 0FS, United Kingdom.
Caterina
C
Ducati
CrayoNano AS , Otto Nielsens vei 12, NO-7052 Trondheim, Norway.
Helge
H
Weman
CrayoNano AS , Otto Nielsens vei 12, NO-7052 Trondheim, Norway.
Bjørn-Ove
BO
Fimland
Antonius T J
AT
van Helvoort
Au; GaAs; Nanowire; annealing; in situ; solid-state replacement