The silicon nitride (SiN) layer functions as a rigid hard mask during shallow trench isolation (STI) patterning and acts as a robust stop layer during chemical-mechanical planarization (CMP) P1.Following the STI Final Densification Anneal and Wet Deglaze Etch, this SiN layer must be entirely removed to expose the active silicon regions T1.This removal process prepares the substrate for the subsequent Blanket B Well Implant and thermal gate oxide growth steps T1.The stripping process must be high