Illumination optical apparatus and projection exposure apparatus

摘要

An illumination optical apparatus and projection exposure apparatus capable of reducing a light quantity loss when a mask is illuminated with a polarized illumination light. An illumination optical system for illuminating a reticle with an illumination light and a projection optical system for projecting the pattern image of the reticle onto a wafer are provided. An illumination light emitted from an exposure light source in a linearly polarized state in the illumination optical system passes through first and second birefringent members having different fast axis directions and is converted into a polarized state that is substantially linearly polarized in a circumferential direction with the optical axis as the center in an almost specific annular area, and them illuminates the reticle under an annular illuminating condition after passing through a fly-eye lens.

主权项

1. A projection exposure apparatus which projects an image of a pattern on a first object onto a second object, the projection exposure apparatus comprising:
a projection optical system arranged between the first object and the second object that projects the image of the pattern on the first object onto the second object; and an illumination optical system that illuminates the first object with illumination light from a light source, and comprising at least two birefringent members arranged along a traveling direction of the illumination light, wherein a direction of a fast axis of an at least one birefringent member of the at least two birefringent members is different from a direction of a fast axis of another birefringent member of the at least two birefringent members, wherein the at least one birefringent member of the at least two birefringent members has a non-uniform surface; and the at least one birefringent member changes a polarization state of the illumination light passing the at least one birefringent member to consist primarily of S-polarization when the illumination light reaches the first object after the illumination light entering into the at least one birefringent member passes the at least one birefringent member.