Patent ID: 7316958

Claim:
A method of forming a photolithography mask comprising: forming a light-blocking layer on a light-transmitting mask; forming a first resist pattern on a portion of the light-blocking layer; etching an exposed portion of the light-blocking layer to form (i) light-blocking pattern corresponding to one of a complementary N-well and P-well and (ii) a size adjusting region comprising an exposed surface of the light-transmitting mask; forming a second resist pattern on the light-blocking pattern and a portion of the exposed surface of the light-transmitting mask, including a portion of the size adjusting region; and partially etching the exposed surface of the light-transmitting mask by a phase shifting depth to form (i) a phase shifted region and (ii) a non-etched region of the size adjusting region, the non-etched region of the size adjusting region being between the light-blocking pattern and the phase shifted region; wherein the size adjusting region increases a slope of the light intensity at an end portion of the phase shifted region relative to an otherwise identical mask that does not include the size adjusting region.