Methods for fabricating integrated circuits including generating photomasks for directed self-assembly (DSA) using DSA target patterns

A method for fabricating an integrated circuit comprising:

• using a computing system, generating a photomask for forming a DSA directing pattern overlying a semiconductor substrate, wherein the DSA directing pattern is configured to guide a self-assembly material deposited thereon that undergoes directed self-assembly (DSA) to form a DSA pattern, and wherein generating the photomask comprises:
• identifying placement of DSA target patterns in a design layout;
• grouping the DSA target patterns into groups including a first group and defining a first group boundary around the first group;
• determining whether or not a neighboring DSA target pattern that is positioned adjacent to and outside of the first group boundary is less than a predetermined minimal keep-away distance from an adjacent DSA target pattern that is within the first group boundary;
• adjusting the first group boundary to include the neighboring DSA target pattern and the first group to define an adjusted first group boundary around an adjusted first group that includes the first group and the neighboring DSA target pattern when the neighboring DSA target pattern is less than the predetermined minimal keep-away distance from the adjacent DSA target pattern;
• determining whether or not the DSA target patterns in the adjusted first group are DSA compatible;
• and
• generating an output mask pattern using the adjusted first group boundary when the DSA target patterns in the adjusted first group are DSA compatible.

A method for fabricating an integrated circuit comprising:

• using a computing system, generating a photomask for forming a DSA directing pattern overlying a semiconductor substrate, wherein the DSA directing pattern is configured to guide a self-assembly material deposited thereon that undergoes directed self-assembly (DSA) to form a DSA pattern, and wherein generating the photomask comprises:
• checking DSA target patterns that are defined in a design layout and that are grouped into groups including a first group that is within a first group boundary, and wherein checking the DSA target patterns comprises:
• checking whether or not a neighboring DSA target pattern that is positioned adjacent to and outside of the first group boundary is less than a predetermined minimal keep-away distance from an adjacent DSA target pattern that is within the first group boundary;
• and
• comparing the DSA target patterns in the first group to acceptable DSA target patterns and/or unacceptable DSA target patterns that are contained in a DSA pattern library to determine whether or not the DSA target patterns in the first group are DSA compatible;
• and
• generating an output mask pattern using the first group boundary when the DSA target patterns in the first group are DSA compatible.