HF/HCl/H2O/MnO2 System for High-Performance Texturization on Multi-Crystalline Silicon

Abstract

We proposed a HF/HCl/H2O system with manganese dioxide (MnO2) particle as the oxidant to obtain high-performance texturization on multi-crystalline silicon (mc-Si) wafers. The texturization obtained by the HF/HCl/H2O/MnO2 system had a more uniform distribution and a lower surface reflectance than that obtained by the conventional HF/HNO3/H2O system, especially on the surface of diamond wire sawn (DWS) mc-Si wafers. The etching mechanism was revealed by studying the effects of the usage variation of HF, HCl and MnO2. The etching only occurs at the locations where MnO2 particles are deposited on the silicon surface and will self-terminate with the full consumption of MnO2. Thus the texture morphology can be easily controlled by adjusting the usage of MnO2 particles with sufficient HCl and HF. Furthermore, such method is environmentally friendly not to use HNO3.