Ultra-low reflectance, high absorption microcrystalline silicon nano-stalagmite (µc-SiNS)

In this work, microcrystalline silicon nano-stalagmite (μc-SiNS) arrays have been successfully fabricated on glass by catalytic etching process through a template. The template use polystyrene (PS) nanospheres with diameter and density of 30 ~ 50 nm and 10¹⁰/cm², respectively by a modified nano-phase separation of PS-containing block copolymer. The length of μc-SiNS could be controlled by the duration of etching time. The μc-SiNS exhibit ultra-low reflection approximately 0.3% and absorption around 99% over 300 to 800 nm in wavelength.