Formation of compositionally abrupt axial heterojunctions in silicon-germanium nanowires.
We have formed compositionally abrupt interfaces in silicon-germanium (Si-Ge) and Si-SiGe heterostructure nanowires by using solid aluminum-gold alloy catalyst particles rather than the conventional liquid semiconductor-metal eutectic droplets. We demonstrated single interfaces that are defect-free and close to atomically abrupt, as well as quantum dots (i.e., Ge layers tens of atomic planes thick) embedded within Si wires. Real-time imaging of growth kinetics reveals that a low solubility of Si and Ge in the solid particle accounts for the interfacial abruptness. Solid catalysts that can form functional group IV nanowire-based structures may yield an extended range of electronic applications.
Wen
C-Y
CY
School of Materials Engineering and Birck Nanotechnology Center, Purdue University, West Lafayette, IN 47907, USA.
Reuter
M C
MC
Bruley
J
J
Tersoff
J
J
Kodambaka
S
S
Stach
E A
EA
Ross
F M
FM