title: Controlling silicon nanowire growth direction via surface chemistry.
abstract: We report on the first in situ chemical investigation of vapor-liquid-solid semiconductor nanowire growth and reveal the important, and previously unrecognized, role of transient surface chemistry near the triple-phase line. Real-time infrared spectroscopy measurements coupled with postgrowth electron microscopy demonstrate that covalently bonded hydrogen atoms are responsible for the (left angle bracket 111 right angle bracket) to (left angle bracket 112 right angle bracket) growth orientation transition commonly observed during Si nanowire growth. Our findings provide insight into the root cause of this well-known nanowire growth phenomenon and open a new route to rationally engineer the crystal structure of these nanoscale semi-conductors.
authors.affiliation: School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States.
authors.forename: Naechul
authors.initials: N
authors.lastname: Shin
authors.forename: Michael A
authors.initials: MA
authors.lastname: Filler
mesh_terms: D003460:Crystallization / Q000379:methods*; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D012825:Silicon / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D046911:Macromolecular Substances; D012825:Silicon