Method of correcting critical dimension in photomask and photomask having corrected critical dimension using the method

A method of correcting a critical dimension (CD) in a photomask, the method comprising:

• providing a substrate that is transparent with respect to an incident light;
• forming a plurality of shielding patterns on the substrate to form the photomask;
• detecting a CD error region of the shielding patterns;
• and
• forming a correction film on the shielding patterns of the CD error region to vary an intensity of the incident light in the CD error region of the shielding patterns in order to correct non-uniformity of critical dimensions (CDs) of circuit patterns formed on a wafer using the shielding patterns;
• wherein a topology of the correction film on the shielding patterns of the CD error region changes the incident light transmitted through the photomask to decrease the intensity of 0th-order light and to increase the intensity of 1st-order light.