A design, device, system and process for placing slots in active regions (e.g., metal areas). Embodiments of the present invention improve the planarization of metal areas (e.g., lines) and insulators by reducing depressions (e.g., dishing) in the metal areas by including symmetric or square slots inside selected wide metal lines, by adhering to a set of placement rules. Embodiments reduce dishing in copper dual damascene structures. Embodiments reduce data processing requirements for designing and arranging the layout of IC devices and the slots.