Projection exposure apparatus and method employing rectilinear aperture stops for use with periodic mask patterns
AssigneeNikon Corporation
InventorShigeru Hirukawa
Life of this patent
Estimating the term…
Abstract
A projection optical system and method projects and forms an image of a pattern arrayed on a first surface (mask), and exhibiting a periodicity in a predetermined direction (X- or Y-direction), on a second surface (wafer). A stop has an aperture showing a line symmetry with respect to a symmetric axis intersecting an optical axis of the projection optical system and extending in a direction (Y- or X-direction) orthogonal to the predetermined direction and having the outline at least a part of which are rectilinear portions. The stop is disposed on a Fourier transform plane of the first surface within the projection optical system or a surface in the vicinity thereof.
Claims30
A projection optical system for projecting and forming an image of a pattern arrayed on a first surface, and exhibiting a periodicity in a predetermined direction, on a second surface,
- said projection optical system comprising a stop having an aperture showing a line symmetry with respect to a symmetric axis passing through an optical axis of said projection optical system and extending in a direction orthogonal to said predetermined direction and having an outline at least a part of which is rectilinear, said stop being provided on a Fourier transform plane of the first surface within said projection optical system or a plane in the vicinity thereof, said stop limiting, with said aperture having said rectilinear part, an area through which diffracted light generated with said pattern passes.
A projection exposure apparatus comprising:
- a projection optical system for projecting and forming an image of a pattern arrayed on a first surface, and exhibiting a periodicity in a predetermined direction, onto a second surface;
- a stop having an aperture provided on a Fourier transform plane of the first surface within said projection optical system or a plane in the vicinity thereof and showing a line symmetry with respect to a symmetric axis passing through an optical axis of said projection optical system and extending in a direction orthogonal to said predetermined direction and having an outline at least a part of which is rectilinear, said stop limiting, with said aperture having said rectilinear part, an area through which diffracted light generated with said pattern passes;
- and
- an illumination optical system for Köhler-illuminating said first surface with beams of exposure illumination light that are emitted from a surface light source having an outline corresponding to a rectilinear portion of the outline of the aperture of said stop that has a rectilinear shape,
- wherein a mask formed with a pattern to be transferred is set on the first surface, a photosensitive substrate is set on the second surface, and the pattern on said mask is exposed onto said photosensitive substrate through said projection optical system with the light beams from said illumination optical system.
A projection optical system for projecting an image of a pattern arrayed on a first surface, and exhibiting a periodicity in a predetermined direction, onto a second surface, said projection optical system comprising:
- an aperture stop disposed on or in the vicinity of a pupil plane of said projection optical system and having an edge extending in a direction orthogonal to the predetermined direction so as to shield a part of diffracted light generated with said pattern.
A projection exposure apparatus for transferring a pattern formed on a mask, and periodically arrayed in a predetermined direction, onto a photosensitive substrate through a projection optical system, said projection exposure apparatus comprising:
- an aperture stop disposed within or in the vicinity of a pupil plane of said projection optical system and having an edge extending in a direction orthogonal to the predetermined direction so as to shield a part of diffracted light generated with said pattern.
A projection exposure apparatus for forming a pattern formed on a mask on a photosensitive substrate through a projection optical system, comprising:
- an illumination optical system that illuminates said mask;
- a first aperture stop, disposed within a pupil plane of said illumination optical system, that defines rectilinearly at least a part of an outline of a light source image formed on the pupil plane;
- a blind, disposed in a plane conjugate with a pattern surface of said mask in said illumination optical system, that limits an illumination area with which said mask is illuminated;
- and
- a second aperture stop, disposed within a pupil plane of said projection optical system, that defines a rectilinear edge corresponding to a rectilinear edge of said first aperture stop so as to shield a part of diffracted light generated with said pattern.
A projection exposure apparatus for forming a pattern formed on a mask on a photosensitive substrate through a projection optical system, comprising:
- an illumination optical system that illuminates said mask;
- and
- an aperture stop, disposed within or in the vicinity of a pupil plane of said projection optical system, and having a rectilinear edge corresponding to an outline of a light source image formed on a pupil plane of said illumination optical system so as to shield a part of diffracted light generated with said pattern.
A method for making a projection exposure apparatus comprising:
- providing a projection optical system that transfers a pattern formed on a mask, said pattern exhibiting a periodicity in a predetermined direction, onto a substrate;
- and
- providing a first aperture stop disposed within or in the vicinity of a pupil plane of said projection optical system, and having an edge extending in a direction orthogonal to said predetermined direction.
A projection exposure method in which a pattern formed on a first surface, and exhibiting a periodicity in a predetermined direction, is transferred onto a second surface through a projection optical system, wherein:
- an image of said pattern is transferred onto said second surface through an aperture stop while shielding, with said aperture stop, a part of diffracted light generated with said pattern, said aperture stop being disposed on or in the vicinity of a pupil plane of said projection optical system and having an edge extending in a direction orthogonal to said predetermined direction.
A projection exposure method in which a pattern formed on a first surface, and exhibiting a periodicity in a predetermined direction, is transferred onto a second surface through a projection optical system, wherein:
- an image of said pattern is transferred onto said second surface through a stop while shielding, with said stop, a part of diffracted light generated with said pattern, said stop being provided on a Fourier transform plane of the first surface or on a plane in the vicinity thereof within said projection optical system, and having an aperture showing a line symmetry with respect to an axis passing through an optical axis of said projection optical system, extending in a direction orthogonal to said predetermined direction, and having an outline at least a part of which is rectilinear.
Dependencies are inferred from the claim text.