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Temperature dependence of mechanical properties in ultrathin Au films with and without passivation

Published online by Cambridge University Press:  31 January 2011

Patric A. Gruber
Affiliation:
Universität Stuttgart, Institute of Physical Metallurgy, D-70569 Stuttgart, Germany
Sven Olliges
Affiliation:
Laboratory for Nanometallurgy, Department of Materials, Eidgenössische Technische Hochschule (ETH) Zürich, 8093 Zurich, Switzerland
Eduard Arzt
Affiliation:
Universität Stuttgart, Institute of Physical Metallurgy, D-70569 Stuttgart, Germany; Max Planck Institute for Metals Research, D-70569 Stuttgart, Germany; and Leibniz Institute for New Materials (INM), D-66123 Saarbrücken, Germany
Ralph Spolenak*
Affiliation:
Laboratory for Nanometallurgy, Department of Materials, ETH Zurich, 8093 Zurich, Switzerland
*
b)Address all correspondence to this author. e-mail: [email protected]
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Abstract

Temperature and film thickness are expected to have an influence on the mechanical properties of thin films. However, mechanical testing of ultrathin metallic films at elevated temperatures is difficult, and few experiments have been conducted to date. Here, we present a systematic study of the mechanical properties of 80–500-nm-thick polycrystalline Au films with and without SiNx passivation layers in the temperature range from 123 to 473 K. The films were tested by a novel synchrotron-based tensile testing technique. Pure Au films showed strong temperature dependence above 373 K, which may be explained by diffusional creep. In contrast, passivated samples appeared to deform by thermally activated dislocation glide. The observed activation energies for both mechanisms are considerably lower than those for the bulk material, indicating that concomitant stress relaxation mechanisms are more pronounced in the thin film geometry.

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Articles
Copyright
Copyright © Materials Research Society 2008

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References

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