Replica Mold for Nanoimprint Lithography from a Novel Hybrid Resin

Abstract

The use of durable replica molds with high feature resolution has been proposed as an inexpensive and convenient route for manufacturing nanostructured materials. A simple and fast duplication method, involving the use of a master mold to create durable polymer replicas as imprinting molds, has been demonstrated using both UV- and thermal nanoimprinting lithography (NIL). To obtain a high-durability replicating material, a dual UV/thermal-curable, organic-inorganic hybrid resin was synthesized using a sol-gel-based combinatorial method. The cross-linked hybrid resin exhibited high transparency to UV light and resistance to organic solvents. Molds made of this material showed good mechanical properties (Young's modulus = 1.76 GPa) and gas permeability, The low viscosity of the hybrid resin (similar to 29 cP) allowed it to be easily transferred to relief nanostructures on transparent glass substrates using UV-NIL at room temperature and low pressure (0.2 MPa) over a relatively short Lime (80 s). A low surface energy release agent was successfully coated onto the hybrid mold surface without destroying the imprinted nanostructures, even after O-2 plasma treatment. Nanostructures with feature sizes down to 80 nm were successfully reproduced using these molds in both UV- and thermal-NIL processes. After repealing 10 imprinting cycles at relatively high temperature and pressure. no detectable collapse or contamination of the replica surface was observed. These results indicate that the hybrid molds could tolerate repeated UV- and thermal-NIL processes.