Heat and pressure-assisted soft lithography for size-tunable nanoscale structures

Abstract

Polydimethylsiloxane (PDMS) has been widely used as a mold material to fabricate multiscale patterns, owing to its cost-effectiveness, flexibility, and optical transparency. However, it is important to analyze and understand the deformation of nanoscale patterns due to mechanical and thermal inputs during the replication step. Here, we present an analysis of nanoscale deformation of PDMS molds in response to heat and pressure during the repetitive molding process of thermoplastic polymers. The width and height of the nano-sized ridges of PDMS molds decreased as the number of replications of thermoplastic polymers increased. The decoupling experiments showed that the heat and pressure induced considerable deformation of the width and height of nano-sized ridges of PDMS molds. Using the precisely controlled deformation of nanostructures in PDMS molds, we demonstrated that nanostructures of different sizes can be fabricated on representative thermoplastic and UV-curable polymers consistently. ？ 2021 Elsevier B.V.