An integrated circuit (IC) device includes a plurality of metal layers having metal traces, and a plurality of vias interconnecting the metal traces. The presence of vacancies within the metal layers may disrupt the functionality of the IC device if the vacancies migrate to the vias interconnecting the metal layers. To mitigate vacancy migration, stressor elements are formed at the metal traces to form stress effects in the metal traces that, depending on type, either serve to repel migrating vacancies from the via contact area or to trap migrating vacancies at a portion of the metal trace displaced from the contact area. The stressor elements may be formed as stress-inducing dielectric or conductive material overlying the metal traces, or formed by inducing a stress memory effect in a portion of the metal trace itself.