Effect of （2 ×1） Surface Reconstruction on Elasticity of a Silicon Nano-Plate

A semi-continuum approach is developed to describe the effect of （2 ×1） surface reconstruction on the elastic modulus of the silicon nano-plate. Young＇s moduli of a （001） silicon nano-plate along the high-symmetry 100] direction are obtained with and without considering （2 × 1） surface reconstruction. The approach predicts that the nano-plate with unreconstructed （001） surface is elastically softer than the bulk while it exhibits the opposite behaviour with （2 × 1） reconstructed surface. On the （001） surface, the （2 × 1） reconstructed surface dominates the plate as the thickness of the plate scaling decreases to several tens of nanometre. Whether the nano-plate is softer or stiffer depends on bond loss, bond saturation and direction of bond alignment, which have major impacts on the mechanics of the nano-plate.

Effect of （2 ×1） Surface Reconstruction on Elasticity of a Silicon Nano-Plate

A semi-continuum approach is developed to describe the effect of (2×1) surface reconstruction on the elastic modulus of the silicon nano-plate. Young's moduli of a (001) silicon nano-plate along the high-symmetry 100] direction are obtained with and without considering (2×1) surfacereconstruction. The approach predicts that the nano-plate with unreconstructed (001) surface is elastically softer than the bulk while it exhibits the opposite behaviour with (2×1) reconstructed surface. On the (001) surface, the (2×1) reconstructed surface dominates the plate as the thickness of the plate scaling decreases to several tens of nanometre. Whether the nano-plate is softer or stiffer depends on bond loss, bond saturation and direction of bond alignment, which have major impacts on themechanics of the nano-plate.