This paper illustrates the effect of substrate topography on morphology evolution in nanoporous gold (np-Au) thin films. One micron-high silicon ridges with widths varying between 150 nm to 50 µm were fabricated and coated with 500 nm-thick np-Au films obtained by dealloying sputtered gold-silver alloy films. Analysis of scanning electron micrographs of the np-Au films following dealloying and thermal annealing revealed two distinct regimes where the ratio of film thickness to ridge width determines the morphological evolution of np-Au films.
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| http://dx.doi.org/10.1016/j.scriptamat.2015.07.039 | DOI Listing |
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