Patent ID: 7378198

Claim:
A photomask in which, on a transparent substrate having light transmitting properties with respect to exposure light, a mask pattern having light-shielding properties with respect to the exposure light and a light-transmitting portion of the transparent substrate where the mask pattern is not located are provided, characterized in that the mask pattern includes: a semi-light-shielding portion which transmits the exposure light in the same phase as that of the light-transmitting portion; and a phase shifter which transmits the exposure light in a phase opposite to that of the light-transmitting portion, the semi-light-shielding portion has a transmittance which allows the exposure light to be partially transmitted, the phase shifter is provided in a region of the mask pattern in which light transmitted through the phase shifter can cancel part of light transmitted through the light-transmitting portion and the semi-light-transmitting portion, and the mask pattern is surrounded by the light-transmitting portion.