Journal article
Time-dependent deformation behavior of freestanding and SiNx-supported gold thin films investigated by bulge tests
Publication Details
Authors: | Merle, B.; Cassel, D.; Göken, M. |
Publisher: | CAMBRIDGE UNIV PRESS |
Publication year: | 2015 |
Journal: | Journal of Materials Research |
Pages range : | 2161-2169 |
Volume number: | 30 |
Issue number: | 14 |
Start page: | 2161 |
End page: | 2169 |
Number of pages: | 9 |
ISSN: | 0884-2914 |
DOI-Link der Erstveröffentlichung: |
Abstract
A novel strain-rate jump method was developed for the plane-strain bulge test and used to investigate the time-dependent deformation behavior of gold thin films in the thickness range 100-400 nm. The experimental method is based on an abrupt variation of the pressurization rate. The evaluated strain-rate sensitivity was found to be five times higher for films in freestanding condition (m = 0.094) than for films tested on a SiNx substrate (m = 0.020). Bulge creep tests confirmed this increased time-dependence. The observation of the surface of the freestanding films after the creep tests provided evidence of apparent grain boundary sliding taking place next to intragranular plastic deformation. The out-of-plane deformation was presumably favored by the columnar microstructure of the samples, with grains extending between both free surfaces. In the case of SiNx-supported films, grain boundary sliding was prevented by the good adhesion of gold to the SiNx substrate.
A novel strain-rate jump method was developed for the plane-strain bulge test and used to investigate the time-dependent deformation behavior of gold thin films in the thickness range 100-400 nm. The experimental method is based on an abrupt variation of the pressurization rate. The evaluated strain-rate sensitivity was found to be five times higher for films in freestanding condition (m = 0.094) than for films tested on a SiNx substrate (m = 0.020). Bulge creep tests confirmed this increased time-dependence. The observation of the surface of the freestanding films after the creep tests provided evidence of apparent grain boundary sliding taking place next to intragranular plastic deformation. The out-of-plane deformation was presumably favored by the columnar microstructure of the samples, with grains extending between both free surfaces. In the case of SiNx-supported films, grain boundary sliding was prevented by the good adhesion of gold to the SiNx substrate.
