Chemical functional polymers for direct UV assisted nanoimprinting of polymeric photonic microring resonators

Abstract

Abstract We report the nanoimprinting of a microring resonator (MRR) and the development of a functional nanoimprint polymer as route toward selective MRR biosensors. A hybrid, residual layer‐free, UV assisted nanoimprint technique was used to pattern freestanding polymer waveguides with a resolution of 300 nm and an aspect ratio of 4:1. A low viscous, functional UV nanoimprint polymer was formulated with a hydroxyl functional acrylate monomer (4‐hydroxyl butyl acrylate, HBA). The functional polymer was characterized by X‐ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). The added hydroxyl groups were found on the polymer surface and were accessible for selective binding of a fluorine tag (trifluoroacetic anhydride, TFAA). The density of the hydroxyl groups was tuned by the HBA concentration. A maximum hydroxyl group density of 8.4% was reached for 33.75 wt% HBA. The RMS surface roughness was 1.2–2.2 nm. magnified image Polymeric photonic MRR with superficial chemical functionalities for a subsequent biomolecule binding and application as a biosensor.