Porous Silicon Layer by Electrochemical Etching for Silicon Solar Cell

Abstract

An Electrochemical etching was used to form the porous silicon (PS) layer on the surface of the crystalline silicon wafer. The PS layer, in this study, will act as an antireflection coating to reduce the reflection of the incident light into the solar cell. The etching solution (electrolyte) was prepared by mixing HF (50%) and ethanol which was introduced for efficient bubble elimination on the silicon surface during etching process. The anodization of the silicon surface was performed under a constant current (galvanostat mode of the power supply), and process parameters, such as current density and etching time, were carefully tuned to minimize the surface reflectance of the heavily-doped wafer with sheet resistance between 20-30 / .