Wide geometry recognition by using circle-tangent variable spacing model

Abstract

Wide geometry can be accurately extracted from the physical layout of an integrated circuit through the use of detection circles having diameters equal to a threshold width. Projection regions in the layout are selected, and for each projection region, a detection circle of a threshold width (diameter) is defined. A trim region within each projection region is defined using the associated detection circle, such that a portion of the trim region boundary exhibits tangency to the detection circle. The trim regions, which represent non-wide portions of the layout, are then removed to generate a wide element layout. Because the detection circle is a rotation-independent geometry, the over-extraction and under-extraction problems associated with conventional wide element extraction methods can be eliminated.