Mask process correction methods and methods of fabricating lithographic masks using the same

A method, comprising:

• performing mask process correction (MPC) on a mask tape out (MTO) design layout, said MPC including:
• (i) identifying a plurality of unit cells, each being iterated in the MTO design layout and including curve patterns, convex patterns, concave patterns, and linear patterns, and (ii) performing model-based MPC on a first one of the plurality of unit cells;
• wherein performing MPC further includes applying a single bias to each of the plurality of curve patterns associated with the first one of the plurality of unit cells;
• wherein each of the plurality of curve patterns includes a respective pair of first and second vertices on a curved edge of a corresponding curve pattern;
• wherein applying the single bias includes applying the single bias to at least one of the pairs of first and second vertices to determine a corresponding pair of first and second biased vertices, which are corrected positions of the corresponding first and second vertices on a respective biased curve edge of a biased curve pattern that is constrained to have matching curvature relative to the curved edge of the corresponding curve pattern during said applying the single bias, and
• wherein the method further comprises:
• fabricating a lithographic mask by performing electron beam exposure based on the MTO design layout having only the single bias.

A method, comprising:

• performing mask process correction (MPC) on a mask tape out (MTO) design layout, said MPC including:
• (i) identifying at least one unit cell containing a plurality of curve patterns, convex patterns, concave patterns, and linear patterns, therein, and (ii) performing model-based MPC on the identified at least one unit cell;
• wherein performing MPC further includes applying a single bias to each of the plurality of curve patterns associated with the at least one unit cell;
• wherein each of the plurality of curve patterns includes a respective pair of first and second vertices on a curved edge of a corresponding curve pattern;
• and
• wherein applying the single bias includes applying the single bias to at least one of the pairs of first and second vertices to determine a corresponding pair of first and second biased vertices, which are corrected positions of the corresponding first and second vertices on a respective biased curve edge of a biased curve pattern that is constrained to have matching curvature relative to the curved edge of the corresponding curve pattern during said applying the single bias, and
• wherein the method further comprises:
• fabricating a lithographic mask by performing electron beam exposure based on the MTO design layout having only the single bias.