Fabrication of Three-Dimensional Si-Au Hierarchical Nanostructures by Laser Interference Lithography

This paper reports a method for the fabrication of 3D Si-Au hierarchical nanostructures to improve the optical performances through four-beam laser interference lithography (LIL) and inductively coupled plasma (ICP) etching. The 3D Si-Au hierarchical nanostructures were composed of silicon tapered pillar arrays, Au grids, and Au islands, and they demonstrated wide-angle antireflective properties less than 25% reflection in the entire visible wavelengths. In addition, many special properties could be obtained by displacing the islands and grid of the hierarchical structure with other metal material due to the flexibility of LIL and ICP etching.