Fabrication of self-supporting nanoarchitecture composed of ultrathin SiO₂ films by nano copying

We herein report the fabrication of 3D-structured silicon oxide ultrathin film from nano-sized line patterns on solid substrate and its separation from the solid substrate. After spin-coating of the polymer underlayer on a silicon wafer, organic nanoholes are fabricated by photo-lithography technique. Its surfaces were covered with ultrathin silicon oxide layers(thickness, 20 to 30 nm) by the surface sol-gel process. The silica film was separated from the substrate by dissolving the polymer underlayer in 2-ethoxyethanol and transferred onto alumina membrane. After calcination (500°C, 5h), 3D-structured silicon oxide ultrathin film was observed by SEM, and they preserved the shape of the original template structure. Shape-designed nano architectures become available by the nanocopy approach.