Compression of nanowires using a flat indenter: Elasticity measurement in nanoscale

TL;DR

This paper introduces a novel SEM-based diametrical compression method with a flat punch indenter to measure the lateral elastic modulus of individual nanowires, validated by analytical, simulation, and experimental results.

Contribution

It presents a new experimental technique for nanoscale elasticity measurement using a flat punch indenter within SEM, combined with an analytical Hertz model and finite-element validation.

Findings

Good agreement between analytical, simulation, and experimental results.

Effective characterization of nanowire elasticity at the nanoscale.

Method applicable to anisotropic nanomaterials like silicon.

Abstract

A new experimental approach for the characterization of the lateral elastic modulus of individual nanowires is demonstrated by implementing a micro/nano scale diametrical compression test geometry, using a flat punch indenter inside of a scanning electron microscope (SEM). A 250 nm diameter single crystal silicon nanowire is tested. Since silicon is highly anisotropic, the compression axis of the wire was determined by electron backscatter diffraction (EBSD). A two dimensional analytical closed-form solution based on a Hertz model is presented. The results of the analytical model are compared with those of finite-element simulations and to the experimental diametral compression results and show good agreement.