Pattern exposing method using phase shift and mask used therefor

A pattern exposing method for forming a predetermined resist pattern on a substrate, said pattern exposing method comprising the steps of:

• (a) exposing a resist layer which is formed on the substrate using a reticle which includes a pattern for exposing a corresponding pattern on the resist layer by use of a phase shift of light transmitted through the reticle, said pattern of the reticle being defined by a phase shift layer formed on a transparent reticle substrate and having first and second phase shift parts;
• and
• (b) developing the resist layer so that the predetermined resist pattern is formed on the substrate,
• said step (a) exposing the corresponding pattern on the resist layer using edge parts of the first and second phase shift parts, said first phase shift part having a width such that a closed ring pattern is exposed by the edge parts thereof, said second phase shift part having a width narrower than that of the first phase shift part so that patterns exposed by the edge parts thereof overlap in the form of a single line pattern.