Position controlled nanowire growth through Au nanoparticles synthesized by galvanic reaction.
Semiconductor nanowires have emerged as promising materials for fundamental studies in quantum-confined systems and applications in nanophotonics and electronics, but major challenges remain in controlling nanowire properties, including their position and size. Here, we report a simple and efficient electrochemical process that combines galvanic reaction and electron-beam lithography to selectively synthesize gold nanoparticles that are consequently used for the growth of ordered GaAs nanowire arrays with pre-defined diameter and position. Size and density control of gold nanoparticles is achieved on non-patterned GaAs substrates by changing the reaction time and concentration of Au(3 + ) ions during the galvanic reaction. Spontaneous formation of localized etch pits is observed when the galvanic reaction is constrained to lithography-defined substrate regions, which confines small-diameter Au nanoparticles during the high temperature growth of GaAs nanowire arrays and enables epitaxial growth of well-ordered nanowire structures.
Tseng
Chun-Hao
CH
Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Tambe
Michael J
MJ
Lim
Sung K
SK
Smith
Matthew J
MJ
Gradecak
Silvija
S
D003460:Crystallization / Q000379:methods*; D004595:Electroplating / Q000379:methods*; D006046:Gold / Q000737:chemistry*; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D036103:Nanotechnology / Q000379:methods*; D010316:Particle Size; D013499:Surface Properties
D046911:Macromolecular Substances; D006046:Gold