Plasma‐Induced Maskless Formation of Quasi‐Periodic Nanoripples on Polymeric Substrates

Quasi‐periodic nanostructures on a variety of materials have recently attracted tremendous attention due to their capability to dramatically change the materials’ surface performance and enable a variety of applications. In reported studies, materials are nanostructured by “exotic” preparation strategies such as self‐assembly, cluster ion beams, and femtosecond lasers, not necessarily providing rapid, large‐area, and scalable fabrication based on a widespread technology. Herein, reactive plasma etching is proposed as a conventional technological route for maskless, large‐area, and mass production of quasi‐periodic nanoripples formed on the bottom, adjacent to the electrode, area of polymeric substrates perpendicularly oriented with respect to the electrode. To provide a justification basis for the proposed strategy, a comprehensive modeling framework is employed for the calculation of particle trajectories, which predict the angular and energy distribution of ions reaching the perpendicular substrate. These distributions show ions impinging on the area adjacent to the electrode with high off‐normal angles and high energies, favoring the formation of nanoripples. The density of the formed nanoripples and the degree of their quasi‐periodicity are dependent on ion density, processing time, and the polymer material, enabling the control of such plasma‐induced periodic surface structures that can be paramount for a wide spectrum of applications.