Biomimetic corrugated silicon nanocone arrays for self-cleaning antireflection coatings

Corrugated silicon nanocone (SiNC) arrays have been fabricated on a silicon wafer by two polystyrene-sphere-monolayer-masked etching steps in order to create high-performance antireflective coatings. The reflectance was reduced from above 35% to less than 0.7% in the range 400-1050 nm, and it remained below 0.5% at incidence angles up to 70° at 632.8 nm for both s- and p-polarized light. The fluorinated corrugated SiNC array surface exhibits superhydrophobic properties with a water contact angle of 164°.