Modeling of the elastic modulus of crystalline silicon based on a lattice dynamics approach

Author

Zhang, Weiwei ; Yu, Hong ; Huang, Qing-An

Author_Institution

Key Lab. of MEMS of Minist. of Educ., Southeast Univ., Nanjing, China

fYear

2011

fDate

5-9 June 2011

Firstpage

1416

Lastpage

1419

Abstract

An augmented continuum theory, based on lattice dynamics theories, is developed to examine the elasticity of three-dimensional crystalline Si materials. The second-order elastic constants of Si can be expressed as the function of the force constants, with the modified Keating model. The phonon dispersion relations have been calculated by using the density functional perturbation (DFP) theory, from which the force constants can be extracted. Then the elastic modulus in any crystallographic directions can be calculated. The average deviation of Young´s modulus from experiment is less than 3.8%. This approach is expected to be used in the design of silicon-based MEMS.

Keywords

Young´s modulus; density functional theory; elastic constants; elemental semiconductors; micromechanical devices; phonon dispersion relations; silicon; DFP theory; Si; Young´s modulus; augmented continuum theory; crystalline silicon; density functional perturbation theory; elastic modulus modeling; lattice dynamics theory; modified Keating model; phonon dispersion relations; second-order elastic constants; silicon-based MEMS design; three-dimensional crystalline silicon materials; Dispersion; Elasticity; Force; Lattices; Phonons; Silicon; Elastic modulus; crystalline silicon; lattice dynamics;

fLanguage

English

Publisher

ieee

Conference_Titel

Solid-State Sensors, Actuators and Microsystems Conference (TRANSDUCERS), 2011 16th International

Conference_Location

Beijing

ISSN

Pending

Print_ISBN

978-1-4577-0157-3

Type

conf

DOI

10.1109/TRANSDUCERS.2011.5969583

Filename

5969583