The Post CMP Cleaning step in the MET5 module is positioned immediately after the chemical mechanical planarization of the Cu bulk and the Ta-based barrier liner P2.This process is essential to remove abrasive particles, organic inhibitors, and metallic corrosion products generated during the preceding CMP steps P3.Unlike STI CMP post-cleaning, which primarily targets dielectric residues and cerium oxide particles using harsh oxidizing chemistries A2, this MET5 cleaning step must address electro