Nanoparticle-based etching of silicon surfaces

Abstract

A method () of texturing silicon surfaces () such to reduce reflectivity of a silicon wafer () for use in solar cells. The method () includes filling () a vessel () with a volume of an etching solution () so as to cover the silicon surface) of a wafer or substrate (). The etching solution () is made up of a catalytic nanomaterial () and an oxidant-etchant solution (). The catalytic nanomaterial () may include gold or silver nanoparticles or noble metal nanoparticles, each of which may be a colloidal solution. The oxidant-etchant solution () includes an etching agent (), such as hydrofluoric acid, and an oxidizing agent (), such as hydrogen peroxide. Etching () is performed for a period of time including agitating or stirring the etching solution (). The etch time may be selected such that the etched silicon surface () has a reflectivity of less than about 15 percent such as 1 to 10 percent in a 350 to 1000 nanometer wavelength range.