The present disclosure provides a method and system for modifying a doped region design layout during mask preparation to tune device performance. An exemplary method includes receiving an integrated circuit design layout designed to define an integrated circuit, wherein the integrated circuit design layout includes a doped feature layout; identifying an area of the integrated circuit for device performance modification, and modifying a portion of the doped feature layout that corresponds with the identified area of the integrated circuit during a mask preparation process, thereby providing a modified doped feature layout.