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

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.