Research on ZnO Nanorods Grown on Si Substrate Etched by TMAH as Si Solar Cell Antireflection Layer

An antireflection layer grown on the Si surface of a solar cell can reduce reflection and increase absorption of light. As a result, it can increase the conversion efficiency of the Si solar cell. In this work, (100) Si wafers were anisotropically wet etched by tetramethyl ammonium hydroxide (TMAH) solution and the pyramidal structures were obtained. The minimum reflectivity of etched Si was lower than 6%. Then ZnO nanorods were grown on the Si substrate by a hydrothermal method. The minimum reflectivity of this structure was lower than 3%, better than that from the TMAH etched surface or ZnO nanorods covered surface only. This method has great potential because of its simplicity and high efficiency.