Following the NMOS LDD Ion Implantation, a hardened photoresist mask remains on the wafer and must be completely removed prior to the deposition of the sidewall spacer (SWS) pad oxide A2.Unlike standard lithography steps, the photoresist here has been subjected to energetic dopant bombardment, transforming its upper layer into a highly cross-linked, carbonized crust known as High-Dose Ion-Implanted Photoresist (HDI-PR) P1.If this hardened mask and its associated organic or metallic residues are