Sub-50 nm Surface Nanopatterning via Nano-Seed-Assisted Stereolithography

Abstract

Three-dimensional (3D) printing based on stereolithography (SLA) enables microstructured objects, but sub-100 nm surface resolution remains difficult because of photopolymerization and resin diffusion. Here, we present a nano-seed-assisted SLA method for integrating sub-50 nm surface nanopatterns with 3D-printed structures. Si master molds with diverse nanoscale geometries are replicated into polymethyl methacrylate (PMMA) nano-seed templates, enabling controlled resin infiltration and high-fidelity pattern transfer from 250 nm to micrometer scales, including dots, holes, waves, and crosses. A conformal ultrathin inorganic barrier layer, such as platinum (Pt) or Ga2O3, suppresses resin-polymer intermixing, confines curing at the interface, and preserves pattern integrity. The method yields uniform sub-50 nm nanopatterns over chip-scale and larger areas up to 45 & times; 75 mm, verified by high-resolution TEM and elemental mapping. It integrates decorative or functional nanopatterns with complex 3D objects, exemplified by a 3D-printed Buddha sculpture. In addition to the hybrid assembly of separately prepared nanopatterned inserts, we further demonstrate the direct fabrication of a monolithic Buddha structure containing a localized nano-seed-derived patterned region, confirming that nanoscale surface ornamentation can be incorporated during the SLA printing process without requiring post-print assembly. Overall, nano-seed-assisted SLA offers a scalable route to high-resolution nanostructuring in 3D-printed materials.