Optical arrangement for exposure apparatus
AssigneeCanon Kabushiki Kaisha
InventorSeiji Takeuchi
Life of this patent
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Abstract
An optical arrangement includes a diffractive optical element and a curvature control system for changing curvature of the diffractive optical element. The optical arrangement can be incorporated into an exposure apparatus having an illuminating system for illuminating a mask having a pattern formed thereon and a projecting system for projecting the pattern of the mask onto a wafer, such that the projecting system includes a diffractive optical element and a curvature control system for changing curvature of the diffractive optical element.
Claims27
An optical apparatus, comprising:
- a diffractive optical element having a variable curvature, wherein said diffractive optical element has a relief type diffraction grating, of which a grating pitch decreases from a center toward an edge thereof;
- and
- curvature varying means for varying the curvature of said diffractive optical element.
An exposure apparatus, comprising:
- illuminating means for illuminating a mask having a pattern formed thereon;
- and
- projecting means for projecting the pattern of the mask onto a wafer, said projecting means including (i) a diffractive optical element having a variable curvature, wherein said diffractive optical element has a relief type diffraction grating, of which a grating pitch decreases from a center toward an edge thereof, and (ii) varying means for varying the curvature of said diffractive optical element.
An optical apparatus, comprising:
- a diffractive optical element having a variable curvature, wherein said diffractive optical element has a relief type diffraction grating, of which a grating pitch decreases from a center toward an edge thereof;
- and
- varying means for varying a pressure applied to at least one surface of said diffractive optical element, to thereby change a curvature of said diffractive optical element.
An optical apparatus, comprising:
- a diffractive optical element having a variable curvature, wherein said diffractive optical element has a relief type diffraction grating, of which a grating pitch decreases from a center toward an edge thereof;
- measuring means for measuring a curvature of said diffractive optical element;
- and
- varying means for varying the curvature of said diffractive optical element on the basis of the measurement by said measuring means.
An optical apparatus, comprising:
- a diffractive optical element having a variable curvature, wherein said diffractive optical element has a relief type diffraction grating, of which a grating pitch decreases from a center toward an edge thereof;
- measuring means for measuring a shape of said diffractive optical element;
- and
- varying means for varying the shape of said diffractive optical element on the basis of the measurement by said measuring means.
An exposure apparatus, comprising:
- illuminating means for illuminating a mask having a pattern formed thereon;
- projecting means for projecting the pattern of the mask onto a wafer;
- and
- measuring means for measuring an optical characteristic of said projecting means, wherein said projecting means includes (i) a diffractive optical element having a variable curvature, wherein said diffractive optical element has a relief type diffraction grating, of which a grating pitch decreases from a center toward an edge thereof and (ii) varying means for varying a shape of said diffractive optical element on the basis of the measurement by said measuring means.
Dependencies are inferred from the claim text.