Measurements of the atomistic mechanics of single crystalline silicon wires of nanometer width

Abstract

Tensile deformation behavior of silicon (Si) wires with nanometer widths, synthesized by nanometer-tip contact and successive retraction, was studied by atomistic combined microscopy of high-resolution transmission electron microscopy/scanning probe microscopy. The elastic limit, Young's modulus, and strength of individual Si nanowires were investigated based on the mechanics of materials at an atomic scale. It was found that both Young's modulus and strength increased to $18\ifmmode\pm\else\textpm\fi{}2$ and $5.0\ifmmode\pm\else\textpm\fi{}0.3\phantom{\rule{0.3em}{0ex}}\mathrm{GPa}$, respectively. The elastic limit was $0.10\ifmmode\pm\else\textpm\fi{}0.02$ and fracture strain was estimated to be $0.30\ifmmode\pm\else\textpm\fi{}0.01$. Experimental results show that mechanical properties of Si wires transform due to size reduction from micrometer to nanometer scale.