The formation and control of highly crumpled metal surfaces on a photocurable viscous liquid

Folds, highly deformed structures, have received extensive attention for their nonlinear responses due to a large strain on soft matters. To investigate the folding phenomena, here, we exploit residual tensile stress during metal deposition, which is large enough to compress a thin film coating and introduce a photocurable viscous fluid to decrease the resistance of the substrate against compressive stress. The system has the advantages of the abilities for freezing the highly deformed surfaces by post-UV exposure to the UV-crosslinkable substrate and manipulating the substrate effect by controlling the thickness of the substrate. We theoretically investigated the dependence on the substrate thickness using scaling analysis and demonstrated self-generated ladder and flower-like graphoepitaxial structures originated from the thickness design of the viscous substrate.