Fig. 3: Collapse effect under an asymmetric geometry.
From: Capillary-force-induced collapse lithography for controlled plasmonic nanogap structures

a SEM images of asymmetric rectangle-shaped nanopillars before collapse and b after collapse. c SEM images of asymmetric curved nanopillars before collapse and d after collapse. With the help of nanocohesion between adjacent nanopillars and asymmetric shapes, the collapse direction can be precisely controlled