Illumination optical system, aligner, and process for fabricating device
AssigneeNikon Corporation
InventorOsamu Tanitsu
Life of this patent
Estimating the term…
Abstract
[Problem] Each of pupil intensity distributions at respective points on an illumination target surface is substantially uniformly adjusted. [Solving Means] An illumination optical system to illuminate an illumination target surface (M; W) on the basis of light from a light source (1) is provided with a distribution forming optical system (3, 4, 5) for forming a pupil intensity distribution on an illumination pupil of the illumination optical system, and a correction unit (12) which is arranged at or near a position of the illumination pupil, or, at or near a position optically conjugate with the illumination pupil, in order to correct the pupil intensity distribution, and which changes an emission direction of a beam according to an incidence position of the beam.
Claims20
An illumination optical system which illuminates an illumination target surface with light from a light source, comprising:
- a distribution forming optical system, arranged in an optical path of the illumination optical system, forming a pupil intensity distribution on an illumination pupil of the illumination optical system;
- and
- a correction unit, for correcting the pupil intensity distribution, changing an emission direction of a beam according to an incidence position of the beam, the correction unit being arranged at or near a position of the illumination pupil, or, arranged at or near a position optically conjugate with the illumination pupil.
Dependencies are inferred from the claim text.