Direct UV-imprint lithography using conductive nanofiller-dispersed UV-curable resin

Abstract

In many early investigations of the ultraviolet (UV) imprinting process, imprint resists served as sacrificial etch barrier masks for pattern transfer onto the underlying layer. In this study, conductive photocurable resin incorporating silver nanoparticles was used in UV imprinting for the direct manufacture of electronic device structures. The materials were formulated simply by mixing acrylate-based UV-curable resin with nanosilver colloids. Successful photopolymerization was possible with these formulations without affecting the antistiction-treated surface chemistry of the stamp. Even with the increased viscosity due to silver (Ag) particulate inclusions, resin infiltration into the master patterns several micrometers deep occurred successfully during the imprinting process. Heat treatment and wet chemical etching followed the UV imprinting to shrink the polymer phase even further and to remove imprint residue to complete electrically conductive continuous media based on Ag nanoparticles.