PMMA nanocolumn array fabricated by catalytic etching and nanomolding technique

This study presents a combined self-assembled nano-sphere lithography (SANL) and catalytic etching technique to cost-effectively form an arrayed nano-column on a silicon wafer. The highest aspect ratio of the column fabricated through catalytic etching in this study was approximately 41:1. The electroforming method can convert a silicon nano-column array to a nano-pore array in a metallic stamp. Finally, a hot embossing process was used to mold nano-column arrays on polymethyl methacrylate (PMMA) substrate. The resulting structured PMMA surface exhibited a contact angle of 99.8^o.