Photomask and pattern forming method using photomask

A photomask comprising:

• a transparent substrate;
• and
• a light shield provided to the transparent substrate and shielding an exposure light beam, wherein
• the light shield includes a translucent mask pattern opening,
• the mask pattern opening includes a plurality of translucent regions which are provided to a periphery of a region corresponding to a desired pattern, and allow exposure light beams to be transmitted through at least three different phases, and
• the plurality of translucent regions are configured such that a phase plane of an exposure light beam transmitted through a translucent region of the plurality of translucent regions, the translucent region spaced apart from the region corresponding to the desired pattern, advances more toward an exposure object spaced a predetermined distance apart than a phase plane of an exposure light beam transmitted through a translucent region of the plurality of translucent regions, the translucent region being close to the region corresponding to the desired pattern, such that the exposure light beams that are transmitted through the mask pattern opening form a projection image of the desired pattern on the exposure object.