2020
Nanoscale, Q1
Статьи в журналах
A. Dostovalov, K. Bronnikov, V. Korolkov, S. Babin, E. Mitsai, A. Mironenko, M. Tutov, D. Zhang, K. Sugioka, J. Maksimovic, T. Katkus, S. Juodkazis, A. Zhizhchenko, A. Kuchmizhak. Hierarchical anti-reflective laser-induced periodic surface structures (LIPSSs) on amorphous Si films for sensing applications // Nanoscale 2020, 12, 25, 13431-13441.
Here, we applied direct laser-induced periodic surface structuring to drive the phase transition of amorphous silicon (a-Si) into nanocrystalline (nc) Si imprinted as regular arrangement of Si nanopillars passivated with a SiO2 layer. By varying the laser beam scanning speed at a fixed pulse energy, we successfully tailored the resulting unique surface morphology of the formed LIPSSs that change from ordered arrangement of conical protrusions to highly uniform surface gratings, where sub-wavelength scale ripples decorate the valleys between near-wavelength scale ridges. Along with the surface morphology, the nc-Si/SiO2 volume ratio can also be controlled via laser processing parameters allowing the tailoring of the optical properties of the produced textured surfaces to achieve anti-reflection performance or partial transmission in the visible spectral range. Diverse hierarchical LIPSSs can be fabricated and replicated over large-scale areas opening a pathway for various applications including optical sensors, nanoscale temperature management, and solar light harvesting. By taking advantage of good wettability, enlarged surface area and remarkable light-trapping characteristics of the produced hierarchical morphologies, we demonstrated the first LIPSS-based surface enhanced fluorescent sensor that allowed the identification of metal cations providing a sub-nM detection limit unachievable by conventional fluorescence measurements in solutions.
https://doi.org/10.1039/D0NR02182B
