The Elastic Property of Bulk Silicon Nanomaterials through an Atomic Simulation Method

Jixiao Tao,Yuzhou Sun

doi:10.1155/2016/8231592

Abstract

This paper reports a systematic study on the elastic property of bulk silicon nanomaterials using the atomic finite element method. The Tersoff-Brenner potential is used to describe the interaction between silicon atoms, and the atomic finite element method is constructed in a computational scheme similar to the continuum finite element method. Young’s modulus and Poisson ratio are calculated for[100],[110], and[111] silicon nanowires that are treated as three-dimensional structures. It is found that the nanowire possesses the lowest Young’s modulus along the[100] direction, while the[110] nanowire has the highest value with the same radius. The bending deformation of[100] silicon nanowire is also modeled, and the bending stiffness is calculated.

Highlights

Over the past decade, one-dimensional nanostructures such as nanowires have been extensively studied through both theoretical and experimental methods
The most important one is the silicon nanowire (SiNW) that has been successfully applied in the nanoelectromechanical devices such as field effect transistors (FETs) [1,2,3] due to their unique optoelectronic and mechanical properties [4, 5]
An atomic element contains 17 atoms for the bulk silicon crystal, and the global stiffness matrix and nonequilibrium force vector are assembled similar to the continuum finite element method (FEM)

Summary

Introduction

One-dimensional nanostructures such as nanowires have been extensively studied through both theoretical and experimental methods. The molecular dynamics and density functional theory [6,7,8,9] are the common atomic scale simulating methods to study the elastic property of nanostructures. Their computational cost is very huge and they are valid only for the small size structures. The present work extends its application to three-dimensional nanostructures in order to study the fine elastic property of SiNWs. An appropriate type of Tersoff-Brenner potential is employed to describe the atomic interaction.

Atomic Scale Modeling Method for Bulk Silicon

Results and Discussions

Conclusions