Investigation of anti-reflection properties of crystalline silicon solar cell surface silicon nanowire arrays

Abstract

In order to trap more sunlight onto the crystalline silicon solar cell and improve the photo-electric conversion efficiency, it is very important to study the optical scattering properties of silicon nanowire arrays on silicon wafer. The rigorous coupled wave analysis method is used for optical simulation, and the Taguchi method is used for efficient optimization. The simulation results show that at the above-mentioned wavelengths the reflectance of the optimized structure is less than 2%, and also able to achieve the wide-angle antireflection. At room temperature and ambient pressure, the silicon nanowire arrays each with a period of 50 nm, duty ratio of 0.6 and height of 1000 nm are successfully prepared on mono-crystalline Si wafers using a novel metal-catalyzed chemical etching technique, the reflectance test results are consistent with simulation values. The average reflectance of the optimized structure over the above-mentioned wavelength range is 4%-5%, showing that the antireflection effect is obvious compared with the reflectivity of about 35% of the single crystal silicon. The minus reflection microstructures reduce the sun battery microstructure costs, at the same time, reduce the monocrystalline silicon surface light reflecting loss, improve the photoelectric conversion efficiency.