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Dependence of confined plastic flow of polycrystalline Cu thin films on microstructure

Published online by Cambridge University Press:  11 July 2016

Yang Mu
Department of Mechanical and Industrial Engineering, Louisiana State University, Baton Rouge, Louisiana 70803, USA
Xiaoman Zhang
Department of Mechanical and Industrial Engineering, Louisiana State University, Baton Rouge, Louisiana 70803, USA
J.W. Hutchinson
School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA
W.J. Meng*
Department of Mechanical and Industrial Engineering, Louisiana State University, Baton Rouge, Louisiana 70803, USA
Address all correspondence to W.J. Meng at
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Axial compression was conducted on micro-pillars, in which polycrystalline Cu thin films were sandwiched between CrN and Si. Plastic flow of Cu was achieved, when the Cu films are inclined either at 90° or 45° with respect to the pillar axis. The texture of Cu films was altered by changing the template on which film growth occurred. The Cu microstructure was further altered by post-deposition annealing. The flow stress shows little dependence on the film texture in the as-deposited state. However, annealing influences the flow stress of confined Cu films significantly. The implications on strain gradient plasticity models are discussed.

Research Letters
Copyright © Materials Research Society 2016 

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