Engineered Biomimicry Chapter 12. Biomimetic Antireflection Surfaces

The compound eyes of moths are composed by hexagonal arrays of non-close-packed nipples that exhibit low reflectance. The outer surface of the cornea of a moth consists of periodic arrays of conical protuberances, termed corneal nipples, typically of sub-250nm height and spacing. These arrays of subwavelength nipples generate a graded transition of refractive index, leading to minimized reflection over a broad range of wavelengths and angles of incidence. In this chapter, the fabrication, characterization, and modeling of moth-eye antireflection coatings on both transparent substrates (e.g., glass) and semiconductor wafers (such as crystalline silicon and GaAs) are discussed.