Mask having balance pattern and method of patterning photoresist using the same

A method of patterning a photoresist using a mask, comprising:

• carrying out an exposure process on a wafer on which the photoresist is coated using the mask, the mask having a first mask region with a plurality of dense patterns and a second mask region with balance patterns regularly arranged around the first mask region;
• and
• patterning the photoresist of a first wafer region corresponding to the first mask region on the exposed wafer,
• wherein the balance patterns inhibit a rapid chemical imbalance from occurring at a boundary between the first and second wafer regions based on a pitch of the balance patterns and the photoresist in the second region remains or is removed based on a duty of the balance patterns.