TWO LEVEL-SET BASED APPROACH FOR TRITONE ATTENUATED PHASE SHIFT MASKS (attPSM) AND RELATED APPLICATIONS

A non-transitory computer-readable medium, storing program instructions executable on a computer system for performing a computer-implemented method for determining information for a photomask, wherein the computer-implemented method comprises:

• determining tone of a photomask as a function of position on the photomask by applying predefined rules to reference data for the photomask when multiple level sets of the photomask overlap, wherein the photomask has three or more tones, and wherein the multiple level sets comprise three or more definitions for the three or more tones, respectively;
• and
• determining information for the photomask from the determined tone as the function of the position on the photomask.

A computer-implemented method for determining information for a photomask, comprising:

• determining tone of a photomask as a function of position on the photomask by applying predefined rules to reference data for the photomask when multiple level sets of the photomask overlap, wherein the photomask has three or more tones, and wherein the multiple level sets comprise three or more definitions for the three or more tones, respectively;
• and
• determining information for the photomask from the determined tone as the function of the position on the photomask, wherein determining the tone and determining the information are performed by a computer system.