Method for designing alternating phase shift masks

摘要

A method of designing an alternating phase shifting mask for projecting an image of an integrated circuit design having a plurality of spaced segments of critical dimension. The method initially identifies a phase universe boundary, such that the phase universe comprises a contiguous region of the integrated circuit layout wherein critical dimension segments within the phase universe are beyond a maximum phase interaction distance from any critical dimension segments outside the phase universe in accordance with predetermined design rules. The method then divides the phase universe into phase regions separated by the integrated circuit layout and any extensions of the critical dimension segments so that the phase regions are binary colorable within the phase universe.