The NMOS Lightly Doped Drain (LDD) Ion Implantation (IIP) - Photo step is a critical photolithography process that defines the spatial boundaries for the subsequent n-type shallow extension implants A2.Situated immediately after gate stack formation and cleaning, this step applies a photoresist mask to expose only the NMOS active regions while protecting PMOS devices and isolation structures P1.This photolithography step fundamentally differs from the earlier NMOS VT Adjust IIP - Photo, which de