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A New Technique for Measuring Poisson's Ratio of Mems Materials

Published online by Cambridge University Press:  15 February 2011

W. N. Sharpe Jr.,
Affiliation:
ME Department, Johns Hopkins University, Baltimore, MD 21218, sharpe@jhu.edu
K. R. Vaidyanathan
Affiliation:
MER Corporation, Tucson, AZ 85706
Bin Yuan
Affiliation:
ME Department, Johns Hopkins University, Baltimore, MD 21218, sharpe@jhu.edu
R. L. Edwards
Affiliation:
Applied Physics Laboratory, Johns Hopkins University, Laurel, MD 20723
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Abstract

New techniques and procedures for measuring Poisson's ratio of MEMS materials are presented. Tensile specimens of polysilicon that are 3.5 μm thick are pulled in a small test machine that has a linear air bearing to eliminate friction. Biaxial strain is measured directly by laser-based interferometry from four gold lines deposited on the specimen surface. The value of Poisson's ratio for vapor-deposited polysilicon is 0.22 +/- 0.01 as determined from 19 tests..

Type
Research Article
Copyright
Copyright © Materials Research Society 1997

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