Young's modulus of thin films by speckle interferometry

Abstract

Speckle interferometry has been applied to the measurement of Young's modulus in thin films. The present study has two novel aspects: the specimens used were approximately 1 µm thick and less than 1 mm long, so the speckle images were obtained by photomicroscopy; and the digital images were analysed by quantitative treatment at intense speckles, rather than by the more standard techniques. Displacements and strains within the gauge length were obtained with low statistical uncertainties. Young's modulus values for three varieties of copper thin films were obtained. All were lower than the polycrystalline bulk average value and the electrodeposited film's modulus was lower than those of both the vapour-deposited films.

Ink‐Jet Printing, Self‐Assembled Polyelectrolytes, and Electroless Plating: Low Cost Fabrication of Circuits on a Flexible Substrate at Room Temperature

“…This is particularly evident in electric deformation. The metal thin films often appear to be more compliant than their bulk equivalents, [70,71] presumably for microstructural reasons such as imperfectly formed grain boundaries. The increase of the yield stress with decreasing grain size is customarily expressed by an inverse power law, known as the HallPetch relation.…”

Standalone Tensile Testing of Thin Film Materials for MEMS/NEMS Applications

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Mechanical characterization of thin films

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