Fabrication and characterization of high-performance anti-reflecting nanotextured Si surfaces for solar cells

Abstract

Experimental results on application of metal-assisted chemical etching (MACE) method for fabricating different morphologies on the surface of Si wafer, and the comparison of their optical properties in terms to develop structures with low reflectivity and high light absorption are presented. In order to obtain efficient anti-reflecting surfaces, Si nanowire arrays, and complex structures composed of micropyramids obtained by conventional alkali chemical etching and Si nanowires prepared by MACE method on the side faces of pyramids were produced on Si wafers. It was found that micropyramids textured by Si nanowires with an average diameter of 130 nm and 325 nm in height, show the highest absorbance (about 98%) and the lowest reflectance (less than 1%) values in the wavelength range 300-1100 nm. In comparison, the reflection of Si nanowire arrays prepared by MACE method was found to be 4%.