2017 Volume 10 Pages E17-002-1-E17-002-6
We proposed a novel fabrication method of a self-standing curved film with pillar-shaped hole patterns using spherical soft ultraviolet (UV) imprint lithography. Spherical soft UV imprint lithography was performed using a patterned polydimethylsiloxane (PDMS) mold and a convex mold. The mother molds were prepared using a unique three-dimensional (3D) printer system and replicated by PDMS molding method. By exploiting the low surface free energy and elasticity of the PDMS molds, a patterned thin curved film with a curvature radius of 40 mm was realized without any significant cracks, and the hole pattern size was obtained with an error of less than 5%. Moreover, by applying appropriate force, a zero-residual-layer imprint was successfully achieved maintaining the accuracy of the hole pattern. These results indicate that the proposed spherical soft UV imprint lithography is applicable for fabrication of 3D structures and 3D functional devices.