Novel thermoplastic polymers with improved release properties for thermal NIL

Abstract

In the nanoimprint lithography (NIL) process the mould release is a limiting step. Regardless of the carefully designed special properties a resist may have, it has to come over this challenging process step to be employed in a NIL process. Generally, the moulds are coated with anti-sticking layers. Here, an alternative solution is developed by modification of two well-established NIL polymers through integration of fluorinated additives in their formulation. An effective additive concentration window was successfully defined, in which the substrate adhesion and imprint behaviour is not influenced. Defect-free patterning down to 30nm is possible. A release force reduction of about 40% was observed with the modified polymer mr-I 7000R compared to the unmodified original.