Improved broadband and quasi-omnidirectional anti-reflection properties with biomimetic silicon nanostructures.
Nature routinely produces nanostructured surfaces with useful properties, such as the self-cleaning lotus leaf, the colour of the butterfly wing, the photoreceptor in brittlestar and the anti-reflection observed in the moth eye. Scientists and engineers have been able to mimic some of these natural structures in the laboratory and in real-world applications. Here, we report a simple aperiodic array of silicon nanotips on a 6-inch wafer with a sub-wavelength structure that can suppress the reflection of light at a range of wavelengths from the ultraviolet, through the visible part of the spectrum, to the terahertz region. Reflection is suppressed for a wide range of angles of incidence and for both s- and p-polarized light. The antireflection properties of the silicon result from changes in the refractive index caused by variations in the height of the silicon nanotips, and can be simulated with models that have been used to explain the low reflection from moth eyes. The improved anti-reflection properties of the surfaces could have applications in renewable energy and electro-optical devices for the military.
Huang
Yi-Fan
YF
Chattopadhyay
Surojit
S
Jen
Yi-Jun
YJ
Peng
Cheng-Yu
CY
Liu
Tze-An
TA
Hsu
Yu-Kuei
YK
Pan
Ci-Ling
CL
Lo
Hung-Chun
HC
Hsu
Chih-Hsun
CH
Chang
Yuan-Huei
YH
Lee
Chih-Shan
CS
Chen
Kuei-Hsien
KH
Chen
Li-Chyong
LC
D040761:Biomimetic Materials / Q000737:chemistry*; D003460:Crystallization / Q000379:methods*; D008027:Light; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D036103:Nanotechnology / Q000379:methods*; D055096:Optical Devices; D010316:Particle Size; D010783:Photometry / Q000379:methods*; D012542:Scattering, Radiation; D012825:Silicon / Q000737:chemistry*; D013499:Surface Properties
D046911:Macromolecular Substances; D012825:Silicon