Plasma Deposition and Nanotechnology

Highly-ordered silicon (Si) nanoripples with remarkable surface properties are of interest for various applications and theoretical studies. However, conventional nanopatterning techniques typically involve a limited processing area and require high energies-often reaching several hundred keV, which constrains their applicability to broader field such as thin films. Accordingly, it is necessary to develop nanopatterning processes in the low-energy regime and understand the mechanism of self-organized nanopattern formation therein. In this study, self-organized Si nanoripples were fabricated using a radiofrequency (RF)-biased inductively coupled plasma (ICP) under the low-ion energy regime. The formation and structural characteristics of the nanoripples were found to be strongly influenced by the ion energy and current density incident on the surface. The angle of ion incidence played a critical role in defining the ripple orientation: at oblique incidence angles, the ripples aligned perpendicular to the ion direction, whereas at normal incidence, randomly oriented ripples were observed. These findings provide valuable insights into plasma–surface interactions and advance the development of low-energy, self-organized nanopatterning processes suitable for broader applications.

Funding acknowledgement

This research was supported by the Technology Innovation Program, funded by the Ministry of Trade, Industry & Energy (MOTIE, Korea) (grant no. RS-2024-00507767, 00508070, 2410000200, 2410000258, 2410003567), the Ministry of Science and ICT (grant no. RS-2025-02413231) and the R&D Convergence Program of the National Research Foundation (NRF) of Korea (grant no. CRC20015-000), Korea Evaluation Institute of Industrial Technology (KEIT) (grant no. RS-2025-02222140), the Korea Semiconductor Research Consortium (KSRC) (grant no. 00235950, 00237058), the Korea Research Institute of Standards and Science (grant no. KRISS GP2025-0013-02), and the 2023 Korea Aerospace University Faculty Research (grant no. 202300250001)