Fabrication of two-dimensional periodic structures on silicon after scanning irradiation with femtosecond laser multi-beams

- Combined 2D periodic structures were fabricated in water and air by scanning femtosecond laser multi-beams over the silicon surface, with the assistance of a microlens array (MLA). The method was a one-step method and the structures could be controlled by the processing parameters.
- The 2D periodic structures include grooves with period of several microns and laser-induced ripples with period of several hundred nanometers.
- Large-area grid-like structures with ripples were fabricated and the antireflection properties of the structured surface were tested.