Functional epoxy polymer for direct nano-imprinting of micro-optical elements

摘要

This work presents a functional resist for the direct fabrication of micro-optical elements with UV-enhanced substrate conformal imprint lithography (UV-SCIL). This functional resist is based on a UV-cur-able epoxy polymer where TiO_2 nanoparticles are enclosed. Adding these particles to the polymer raises the refractive index of the functional resist with raising particle content from 1.52 up to 1.64 at a wavelength of 633 nm. Therefore, the refractive index can be matched for many micro-optical applications. Here, multilevel Fresnel lenses from a 200 mm silica substrate are transferred into the functional resist by UV-SCIL with nanometer resolution and high structure fidelity.