Spin Cast PDMS Film Supported Versatile and Transferrable Block Copolymer Lithography

Abstract

Block copolymer (BCP) lithography offers a promising lithographical tool for next generation nanodevices. Among commonly used BCPs, polystyrene-b-poly(methyl methacrylate) (PS-b-PMMA) has a good compatibility with conventional device fabrication process, based on the thermally driven self-assembly behavior. Nonetheless, PS-b-PMMA suffers from low etch selectivity between PS and PMMA. We present PS-b-PMMA nanotemplates assembled on spin cast PDMS thin films for versatile transferrable nanopatterning of various substrates. In this approach PDMS thin films play the multiple roles of sacrificial transfer layer and etching mask to compensate the low etch selectivity of PS-b-PMMA. Significantly, BCP templates integrated with PDMS films can be readily transferred onto other substrates including polymer substrates, over which BCP self-assembly involved with high temperature annealing and solvent treatment is not allowed. In addition, our approach is compatible with practical device fabrication processes in conjunction with DSA principles, such as soft-graphoepitaxy for device-oriented laterally ordered nanopatterns.