Perforated polymer membranes fabricated by nanoimprint

A bi-layer process was developed based on a polymeric sacrificial layer to generate free-standing polymer membranes. Regular hole patterns were generated in the top layer via nanoimprint and etched down to the sacrificial layer using reactive ion etching. The underlying layer was partly dissolved in a wet etching process through the pores, thus creating an air gap. Large arrays with interconnected pores could be fabricated. This process can be applied to a wide selection of polymeric materials and was successfully applied to pore sizes of 200 nm. (c) 2006 Elsevier B.V. All rights reserved.