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Local Strains Measured in Al Lines During Thermal Cycling and Electromigration Using Convergent-beam Electron Diffraction

Published online by Cambridge University Press:  01 July 2005

J. Nucci ,
S. Krämer ,
E. Arzt  and
C.A. Volkert
J. Nucci*
Affiliation:
Max Planck Institute for Metals Research, Stuttgart, Germany
S. Krämer
Affiliation:
Max Planck Institute for Metals Research, Stuttgart, Germany
E. Arzt
Affiliation:
Max Planck Institute for Metals Research, Stuttgart, Germany
C.A. Volkert
Affiliation:
Max Plank Institute for Metals Research, Stuttgart, Germany; and Forschungszentrum Karlsruhe, Karlsruhe, Germany
*
a)Address all correspondence to this author. e-mail: nucci@mf.mpg.de
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Abstract

In situ local measurement of sub-threshold strains generated during the electromigration of a 0.3-μm-wide Al interconnect was performed for the first time using convergent-beam electron diffraction (CBED) in a transmission electron microscope (TEM). Thermal strains were also analyzed and provided verification for the electromigration analysis. Spatially averaged strains resulting from thermal cycling and electromigration quantitatively agree with models and data from previous studies. However, the local strains exhibited variations as large as 2 × 10−3. After eliminating other possible mechanisms, the strain inhomogeneity is attributed to local plasticity through source-limited dislocation activity.

Keywords

ElectromigrationMechanical propertiesMetal

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Type
Articles
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Journal of Materials Research , Volume 20 , Issue 7 , July 2005 , pp. 1851 - 1859
Copyright
Copyright © Materials Research Society 2005

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