| 摘要 |
PROBLEM TO BE SOLVED: To provide an exposure method which can suppress generation of residual resist caused by formation of a dark part due to a shifter edge part and can enlarge exposure margins such as luminous exposure tolerance and focal depth, without any need for a complicated mask structure or a multiple exposure process. SOLUTION: In the exposure method, a projection aligner having an illumination optical system for illuminating a mask 12 and a projection optical system 17 for projecting a pattern of the mask 12 onto a water 20 to form its image thereon is used to illuminate the pattern of the mask 12 on the resist on the wafer 20. At this time, the illumination optical system includes a first illumination optical system 11 for bright-field illumination of σ<1 and second illumination optical systems 13 and 14 for dark-field illumination of σ>1. The mask 12 is a phase shift mask selectively formed with a phase shifter part which provides a phase difference of 180 degrees with respect to exposing light on a transparent substrate. The phase shifter part is formed at its edge portion with a light shield. Exposure based on the bright-field illumination and exposure based on the dark-field illumination are carried out at the same time. |
