Measurement of the bending strength of vapor-liquid-solid grown silicon nanowires.
The fracture strength of silicon nanowires grown on a [111] silicon substrate by the vapor-liquid-solid process was measured. The nanowires, with diameters between 100 and 200 nm and a typical length of 2 microm, were subjected to bending tests using an atomic force microscopy setup inside a scanning electron microscope. The average strength calculated from the maximum nanowire deflection before fracture was around 12 GPa, which is 6% of the Young's modulus of silicon along the nanowire direction. This value is close to the theoretical fracture strength, which indicates that surface or volume defects, if present, play only a minor role in fracture initiation.
Hoffmann
Samuel
S
EMPA Materials Science and Technology, Feuerwerkerstrasse 39, 3602 Thun, Switzerland. samuel.hoffmann@empa.ch
Utke
Ivo
I
Moser
Benedikt
B
Michler
Johann
J
Christiansen
Silke H
SH
Schmidt
Volker
V
Senz
Stephan
S
Werner
Peter
P
Gösele
Ulrich
U
Ballif
Christophe
C
D003198:Computer Simulation; D003460:Crystallization / Q000379:methods*; D004548:Elasticity; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing / Q000379:methods*; D019563:Mechanics; D018625:Microscopy, Atomic Force / Q000379:methods*; D008956:Models, Chemical; D008968:Molecular Conformation; D036103:Nanotechnology / Q000379:methods; D043942:Nanotubes / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D011485:Protein Binding; D012825:Silicon / Q000737:chemistry*; D013314:Stress, Mechanical; D013718:Tensile Strength
D046911:Macromolecular Substances; D012825:Silicon