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. An illumination optical apparatus which illuminates a pattern on a mask with illumination light through a pupil plane of the illumination optical apparatus, the illumination optical apparatus comprising:
an optical integrator arranged in an optical path of the illumination light on an incidence side of the pupil plane; a plurality of birefringent members made of a birefringent material, which are arranged in the optical path on an incidence side of the optical integrator and arranged in order in a direction along an optical axis of the illumination optical apparatus so as to change a polarization state of the illumination light; and a distribution changing member arranged in the optical path between the plurality of birefringent members and the optical integrator so as to change a light quantity distribution of the illumination light on the pupil plane, the light quantity distribution including a light quantity in a first region larger than a light quantity in a second region, the first region being away from the optical axis, the second region including the optical axis, wherein the plurality of birefringent members change the polarization state of the illumination light entering into the plurality of birefringent members in a substantially single polarization state so that a polarization state of the illumination light in the first region consists primarily of linear polarization of which a polarization direction is substantially coincident with a circumferential direction about the optical axis.