Fabrication of Nanoscale Oxide Textured Surfaces on Polymers

Abstract

Nanoscale textured surfaces play an important role in creating antibacterial surfaces, broadband anti-reflective properties, and super-hydrophobicity in many technological systems. Creating nanoscale oxide textures on polymer substrates for applications such as ophthalmic lenses and flexible electronics imposes additional challenges over conventional nanofabrication processes since polymer substrates are typically temperature-sensitive and chemically reactive. In this study, we investigated and developed nanofabrication methodologies to create highly ordered oxide nanostructures on top of polymer substrates without any lithography process. We developed suitable block copolymer self-assembly, sequential infiltration synthesis (SIS), and reactive ion etching (RIE) for processes on polymer substrates. Importantly, to prevent damage to the temperature-sensitive polymer and polymer/oxide interface, we developed the process to be entirely performed at low temperatures, that is, below 80 °C, using a combination of UV crosslinking, solvent annealing, and modified SIS and RIE processes. In addition, we developed a substrate passivation process to overcome reactivity between the polymer substrate and the SIS precursors as well as a high precision RIE process to enable deep etching into the thermally insulated substrate. These methodologies widen the possibilities of nanofabrication on polymers.

Sequential Infiltration Synthesis for High-Precision Fabrication of Applied Ceramic Fibers with Designed Nanostructures─Nanowires, Nanobelts, and Core–Shell Fibers

“…The SIS cycle is completed by exposure to a co-reactant, resulting in the formation of inorganic clusters within the free volume of the polymer. − After growth, the polymer template can be removed to yield an inorganic structure. SIS has been demonstrated with a variety of materials such as AlO x , TiO x , ZnO, VO x , InO x , and SnO x , using diverse polymer chemistries and template geometries, including films, foams, particles, and membranes. − The use of SIS within polymer fibers can give rise to synthetic composite fibers with synergistic properties, as demonstrated by Parsons and co-workers. , Yet, the great potential of SIS as a highly tunable inorganic fiber fabrication process has not been probed. The rational design of SIS processes in polymer fibers can open the path to a variety of fiber morphologies and materials, all fabricated through a single process using a high-precision ALD tool.…”