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Thickness dependence of flow stress of Cu thin films in confined shear plastic flow

Published online by Cambridge University Press:  25 September 2014

Yang Mu ,
Ke Chen  and
W.J. Meng
Yang Mu
Affiliation:
Department of Mechanical and Industrial Engineering, Louisiana State University, Baton Rouge, Louisiana 70803
Ke Chen
Affiliation:
Department of Mechanical and Industrial Engineering, Louisiana State University, Baton Rouge, Louisiana 70803
W.J. Meng*
Affiliation:
Department of Mechanical and Industrial Engineering, Louisiana State University, Baton Rouge, Louisiana 70803
*
Address all correspondence to W.J. Meng at[email protected]
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Abstract

Compression loading on CrN/Cu/Si(100) micropillars containing 45°-inclined interfaces yielded unequivocal evidence of shear plastic flow within Cu thin films confined between non-deforming Si and CrN. Confined shear plastic flow occurred over Cu thicknesses between ~100 and 1200 nm, with a monotonically increasing flow stress as the thickness decreases. The demonstration of a significant dependence of the shear flow stress on the confined Cu film thickness offers a new example of scale-dependent plasticity, and a new experimental test case for non-local plasticity theories.

Type
Research Letters
Information
MRS Communications , Volume 4 , Issue 3 , September 2014 , pp. 129 - 133
Copyright
Copyright © Materials Research Society 2014 

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