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Plasticity Length Scale in LIGA Nickel MEMS Structures

Published online by Cambridge University Press:  15 March 2011

J. Lou
Affiliation:
The Princeton Materials Institute and The Department of Mechanical and Aerospace Engineering, Princeton University, Olden Street, Princeton, NJ 08544
P. Shrotriya
Affiliation:
The Princeton Materials Institute and The Department of Mechanical and Aerospace Engineering, Princeton University, Olden Street, Princeton, NJ 08544
S. Allameh
Affiliation:
The Princeton Materials Institute and The Department of Mechanical and Aerospace Engineering, Princeton University, Olden Street, Princeton, NJ 08544
N. Yao
Affiliation:
The Princeton Materials Institute and The Department of Mechanical and Aerospace Engineering, Princeton University, Olden Street, Princeton, NJ 08544
T. Buchheit
Affiliation:
Mechanical Reliability and Modeling Dept., Sandia National Laboratories, Albuquerque, NM 87185
W.O. Soboyejo
Affiliation:
The Princeton Materials Institute and The Department of Mechanical and Aerospace Engineering, Princeton University, Olden Street, Princeton, NJ 08544
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Abstract

The plasticity length scale parameters associated with rotational and stretch gradients in LIGA nickel MEMS structures plated from sulfamate bath are presented in this paper. These are obtained from micro-bend and micro-tensile experiments on LIGA nickel films with different thicknesses. The composite length-scale parameter, lc is measured to be ∼ 4.8 νm for as-plated films (25, 50, 100 and 175 νm thick). The implications of the results are then discussed for the modeling of plasticity in LIGA nickel structures.

Type
Research Article
Copyright
Copyright © Materials Research Society 2002

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