The Periphery N-Well Contact IIP - Photo step is a critical lithographic operation designed to define the localized regions for heavily doped surface implants within the pre-existing N-Well of the CMOS image sensor's logic circuitry T2.Unlike the Periphery N-Well IIPX mask, which defines the deep, lightly doped body of the well to house PMOS devices, this contact mask strictly targets the surface regions to enable subsequent low-resistance ohmic connections P2.Furthermore, it is distinct from Pi