Figure 1. Evolution of hierarchical surface pattern of gold film on uniaxially pre-strained elastomer substrate.
The thickness of the gold film is 13±1 nm and the uniaxial pre-strain in the substrate is 200%. SEM images (top panel low resolution, bottom panel high resolution) of the gold film under nominal compressive strains of 0% (a), 5% (b), 20% (c) and 67% (d). The scale bars are 10 μm in top panels and 2 μm in bottom panels of (a)–(d). AFM image (e) of the first- and second-level wrinkles and second-level localized ridge on the gold film, and a cross-section (f) of the AFM image. The amplitude of the second-level localized ridge is significantly larger than those of adjacent second-level wrinkles. The scale bar is 2 μm in (e)