Highly parallel fabrication of nanopatterned surfaces with nanoscale orthogonal biofunctionalization imprint lithography

Abstract

Large areas of nanopatterns of specific chemical functionality are needed for biological experiments and biotechnological applications. We present nanoscale orthogonal biofunctionalization imprint lithography (NOBIL), a parallel top-down imprinting and lift-off technique based on step-and-flash imprint lithography (SFIL) that is able to create centimetre-scale areas of nanopatterns of two biochemical functionalities. A photoresist precursor is polymerized with a template in place, and the thin resist layer is etched to create an undercut for lift-off. Gold nano-areas on a silicon dioxide background are then independently functionalized using self-assembly that translates the nanopattern into a cell-adhesive/cell-rejective functionality pattern. We demonstrate the technique by creating fibronectin areas down to a pattern size of 60 nm against a polyethylene glycol (PEG) background, and show initial results of cells stably seeded over an array of 1 mm(2) areas of controlled size and pitch.