To provide a prerequisite capable of developing an exposure device for the next generation by improving the resolution of patterns in a semiconductor process and extending use periods of a current exposure device in order to prevent undesired patterns by forming slits of micropatterns at the ends of mask patterns applying a chromeless phase lithography.

In a photomask 200 for forming photoresist patterns in the manufacturing process of semiconductors, the photomask is achieved such that the patterns are formed at one axis by the chromeless phase lithography, at least one pattern is formed at predetermined angles separated from the patterns, and slits 130,140 of chrome materials are formed at the end of each pattern.