Multi-Level Micro/Nanotexturing by Three-Dimensionally Controlled Photofluidization and its Use in Plasmonic Applications

摘要

Microanotextured surfaces have been utilized to induce many important natural and artificial phenomena: examples include the superhydrophobicity at the surface of a lotus leaf, efficient light trapping in solar cells, rainbow radiation of surface plasmon polaritons (SPPs) on chirped gratings, reversibly switchable adhesion of gecko or aphid's footpad, and omni-directional light reflection at the surface of a morpho butterfly wing. Along the way, the diverse micro/ nanotextured surfaces including dome, sphere, and funnel-shaped tip have been successfully fabricated, both by assembling block copolymer, colloids, CNTs, and nanowires and by imprinting/etching polymeric materials. While most previous approaches for the fabrication of such microanotextured surfaces have mainly focused on the flat surface or top layer of the post array (a single-level microanotexturing), deterministic multi-level microanotexturing has yet to be exploited: "multi-level microanotexturing", herein, refers to selective inscription of distinct surface architectures onto different pre-programmed heights of work surface in order to het-erogeneously integrate various functional surfaces into a single composite.