Figure 1

Optical micrographs showing dewetting of (a) of different samples of a 40 nm PS film ($M_w=0.9\mathrm{Mg}/\mathrm{mol}$) on a $2\mu \mathrm{m}$ PDMS layer at $170°\mathrm{C}$ (${\tau }_{\mathrm{rep}}=2700\sec $) for (from left to right) 5 360  480 and 540 min (size of images: $206\times 206\mu {\mathrm{m}}^2$) and (b) a time series from a single 40 nm PS film ($M_w=1.0\mathrm{Mg}/\mathrm{mol}$) on a 200 nm PDMS layer at $180°\mathrm{C}$ (${\tau }_{\mathrm{rep}}=1200\sec $) for (from left to right) 2, 110, 380, 800, and 900 min (size of images: $58\times 58\mu {\mathrm{m}}^2$). (c) Hole diameter (for uneven holes, a mean diameter of the enveloping perimeter of the hole was taken), and (d) dewetting velocity for the holes labeled by $\mathbf{E}$ (squares) and $\mathbf{L}$ (circles) in panel (b).Reuse & Permissions

Figure 2

(a) Hole diameter ($d$) as a function of dewetting time (for uneven holes, a mean diameter of the enveloping perimeter of the hole was taken) for a 55 nm PS film ($M_w=1.0\mathrm{Mg}/\mathrm{mol}$) dewetting at $130°\mathrm{C}$ (${\tau }_{\mathrm{rep}}=1.2106\sec$) on a 10 nm monolayer of irreversibly adsorbed PDMS molecules (stars), a 360 nm thick (lozenges) and a $2\mu \mathrm{m}$ thick cross-linked PDMS layer (triangles). For comparison, the data from hole “$\mathbf{E}$“ of Fig. 1 (open squares) are replotted (b) Hole diameter as a function of the thickness of the soft rubbery PDMS layer for a 55 nm PS film ($M_w=1.0\mathrm{Mg}/\mathrm{mol}$) dewetting at $130°\mathrm{C}$ measured after different dewetting times as indicated in the figure.Reuse & Permissions

Figure 3

Atomic force microscopy cross section through dewetted holes, indicated by white lines in the corresponding full 2D topography AFM images next to the graph, in a 55 nm PS film ($M_w=1.0\mathrm{Mg}/\mathrm{mol}$) on a 360 nm PDMS layer, dewetting at $140°\mathrm{C}$ (${\tau }_{\mathrm{rep}}=160000\sec $) for (a) 300, (b) 1500, (c) 20 000, (d) 800 000, and (e) 950 000 sec, respectively. The surface of the unperturbed PS film has been set to zero height or depth level. Accordingly, the level of the unperturbed PDMS surfaces is at $-55\mathrm{nm}$. Traces $b$ and $c$ represent the transient depression in the soft substrate.Reuse & Permissions

Figure 4

Depth of the depression within the hole (a) versus dewetting time and (b) versus the diameter of the holes for the samples of Fig. 3 (stars) and a 55 nm PS film ($M_w=5.0\mathrm{Mg}/\mathrm{mol}$) on a 360 nm PDMS layer, dewetting at $130°\mathrm{C}$ (spheres, ${\tau }_{\mathrm{rep}}={2.910}^8\sec $). (c),(d): Schematic representation of the shape of the rim and the trench of a dewetting hole in a PS film deforming the soft rubbery PDMS layer underneath. Because of elastic deformation of the PS film at early stages the corresponding elastic trench is digging into the soft PDMS under-layer quite deeply. At late stages, after the relaxation time ${\tau }_{\mathrm{rep}}$, only a small deformation (viscous trench) due to the normal component of the capillary force at the three phase contact line is left in the PDMS layer.Reuse & Permissions