Automatic layout yield improvement tool for replacing vias with redundant vias through novel geotopological layout in post-layout optimization

摘要

The present invention provides a new way of improving yield in the physical design stage after detail routing, thereby optimizing integrated circuit (IC) layout designs for manufacturing. Embodied in an automatic layout yield improvement tool, the present invention replaces vias with redundant vias having redundant cut shapes or larger metal overlapping based on a novel geotopological approach to routed layout optimization. The geotopological approach enables the most favorable redundant via candidate to be selected for each modifiable regular via. The tool first checks all potential redundant vias in the order of yield favorableness. The modifiable regular via is then replaced by an ideal redundant via that does not introduce any design rule violations in the geotopological layout. Overcoming the fundamental limitation of geometrical-based solutions and taking advantage of the modification flexibility of the geotopological approach, this invention achieves highly desirable redundant via usage rate and substantial yield improvement.