Exposure method and apparatus therefor

An exposure apparatus comprising:

• an illumination optical system for illuminating a pattern formed on a mask with illumination light;
• a projection optical system for projecting an image of said pattern on a photosensitive substrate;
• a member for holding a mask having a phase shifter portion for shifting the phase of the illumination light by about (2n+1).pi. (n is an integer), at an object plane side of said projection optical system;
• and
• optical means for making a light amount distribution of the illumination light around a local region centered on an optical axis of said illumination optical system within a predetermined plane substantially coincident with one of a Fourier transform plane of said mask in said illumination optical system or a plane conjugate thereto stronger than a light distribution within said local region, so as to illuminate said mask with a plurality of beams of the illumination light which are inclined with respect to said optical axis at substantially equal angles corresponding to a fineness of said pattern.

An exposure apparatus comprising:

• an illumination optical system for illuminating a pattern formed on a mask with illumination light;
• a projection optical system for projecting an image of said pattern on a photosensitive substrate;
• a member for holding a mask having a phase shifter portion for shifting the phase of the illumination light by about (2n+1).pi. (n is an integer), at an object plane side of said projection optical system;
• and
• an optical member for making a light amount distribution of the illumination light around a local region centered on an optical axis of said illumination optical system within a predetermined plane substantially coincident with one of a Fourier transform plane of said mask in said illumination optical system or a plane conjugate thereto stronger than a light distribution within said local region, so as to illuminate said mask with a plurality of beams of the illumination light which are inclined with respect to said optical axis at substantially equal angles corresponding to a fineness of said pattern.