Method for designing alternating phase shift masks

An article of manufacture comprising a computer-usable medium having computer readable program code means embodied therein for designing an alternating phase shifting mask for projecting an image of an integrated circuit design, the layout having a plurality of spaced segments of critical dimension, the computer readable program code means in said article of manufacture comprising:

• computer readable program code means for identifying a phase universe boundary, the phase universe comprising 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;
• and
• computer readable program code means for dividing 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.

A program storage device readable by a machine, tangibly embodying a program of instructions executable by the machine to perform method steps for designing an alternating phase shifting mask for projecting an image of an integrated circuit design, the layout having a plurality of spaced segments of critical dimension, said method steps comprising:

• identifying a phase universe boundary, the phase universe comprising 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;
• and
• dividing 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.