Silicon nanowires honeycomb array fabrication with low-cost top-down technology on (111) silicon wafer

This paper presents a low-cost top-down fabrication technology for silicon nanowires (SiNWs) honeycomb array on a monolayer silicon wafer while only conventional micro-fabrication technology is required. Based on the anisotropic wet-etching mechanism for commercial (111) silicon wafer, highly downscaled silicon walls can be formed between the arbitrary adjacent etched cavities with a controllable size-reduction process. By arranging the cavities in a regular array, silicon walls with same width along three orientations can be fabricated synchronously. After the self-limiting oxidation, SiNWs are generated on the top center of each wall with 120° angle forming a honeycomb array.