Interferometer, exposure apparatus and method for manufacturing device
OwnerEiji Aokiinventor
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Abstract
A method for measuring aberration of an optical system that constitutes an interferometer comprises a step of disposing a reflecting member at an image point of the optical system and a step of detecting, by detection means, interference fringes formed based on light that has been emitted from a light source, transmitted through the optical system, caused to illuminate the reflecting member, reflected by the reflecting member and transmitted through the optical system again. The refractive index of the reflecting member with respect to the light is equal to or larger than 1.8.
Claims6
A method for measuring aberration of an optical system that constitutes an interferometer, comprising the steps of:
- disposing a reflecting member at an image point of said optical system;
- and
- detecting, by detection means, interference fringes formed based on light that has been emitted from a light source, transmitted through said optical system, caused to illuminate said reflecting member, reflected by said reflecting member and transmitted through said optical system again;
- wherein a refractive index of said reflecting member with respect to said light is equal to or larger than 1.8.
An exposure apparatus comprising:
- a projection optical system for projecting an original pattern onto a substrate, wavefront aberration of said projection optical system having been measured by an interferometer and aberration of an optical system that constitutes said interferometer having been measure by a method comprising the steps of:
- disposing a reflecting member at an image point of said optical system;
- and
- detecting, by detection means, interference fringes formed based on light that has been emitted from a light source, transmitted through said optical system, caused to illuminate said reflecting member, reflected by said reflecting member and transmitted through said optical system again;
- wherein a refractive index of said reflecting member with respect to said light is equal to or larger than 1.8.
Dependencies are inferred from the claim text.