Exposure method and projection exposure apparatus
AssigneeNikon Corporation
InventorKenji Nishi
Life of this patent
Estimating the term…
Abstract
A projection exposure apparatus carries out scan exposure with illumination flux of slit(s) by moving a mask and a substrate in a direction of one-dimension at synchronized speeds with each other. The mask is inclined with a predetermined angle relative to the substrate in the direction of one-dimensional movement. The substrate is also moved in a direction of optical axis of projection optical system when moved in the direction of one-dimension, such that a central part of transfer area on the substrate is located on a best focal plane of projection optical system upon scan exposure.
Claims48
A method for exposure in which a pattern formed in a transfer region on a mask is subject to projection exposure through a projection optical system to be led onto an area to be exposed on a photosensitive substrate, and said mask and photosensitive substrate are at least one-dimensionally, relatively scanned with respect to a projection field of said projection optical system:
- comprising,
- limiting a width of said area of pattern image projected on said photosensitive substrate through the projection optical system to an approximately constant value in a direction of one-dimensional scan;
- and
- inclining a local surface on said photosensitive substrate on which said pattern image is formed, relative to a best focal plane of said projection optical system in the direction of one-dimensional scan.
A projection exposure apparatus comprising:
- a projection optical system for projecting a pattern formed in a transfer region on a mask, onto an area to be exposed on a photosensitive substrate;
- a mask stage for one-dimensionally moving said mask over a region beyond a width of said transfer region in a direction of movement;
- a substrate stage for one-dimensionally moving said photosensitive substrate in the direction of one-dimensional movement of said mask stage at a speed synchronized with a movement speed of said mask stage;
- illumination means for illuminating said mask with an illumination flux for exposure, having a shape between a rectangle and a slit within the projection field of said projection optical system and having an approximately constant width in the direction of one-dimensional movement;
- a substrate holder the holding said photosensitive substrate on said substrate stage with a predetermined inclination angle with respect to the direction of one-dimensional movement of illuminated area formed by said illumination flux on said photosensitive substrate through said mask and said projection optical system;
- holder drive means for moving said substrate holder in a direction of optical axis of said projection optical system such that a central part of said illuminated area on said photosensitive substrate is located near a best focal plane of said projection optical system;
- and
- control means for controlling said holder drive means to maintain an imaging condition of pattern image of said mask on said photosensitive substrate with correspondence to a position in said illuminated area in the direction of one-dimensional movement while scan exposure of pattern of said mask is effected on said area to be exposed.
A scanning exposure method of exposing a substrate through a projection optical system with an energy beam irradiated on a mask, comprising:
- distributing the energy beam within a field of view of the projection optical system within a plurality of regions extending in a second direction crossing a first direction in which the substrate is moved during scanning exposure of the substrate, and
- moving the substrate relative to the plurality of regions in the first direction in synchronization with movement of the mask during the scanning exposure.
A scanning exposure method of exposing a substrate through a projection optical system with an energy beam irradiated on a mask, comprising:
- moving the substrate relative to the energy beam projected by the projection optical system in synchronization with movement of the mask relative to the energy beam during scanning exposure of the substrate with the energy beam, and
- changing a position of a specified point on the substrate with respect to a direction along the optical axis of the projection optical system during the scanning exposure so that the energy beam is irradiated on the specified point at a plurality of different positions along the optical axis.
A scanning exposure method comprising:
- defining an irradiation region of illumination light on a substrate to a rectangular or slit shape for a scanning exposure of the substrate with the illumination light through a mask and a projection optical system;
- moving the substrate relative to the illumination light, which passes through the projection optical system, in synchronization with movement of the mask relative to the illumination light during the scanning exposure;
- detecting positional information of the substrate with respect to a direction along an optical axis of the projection optical system within the irradiation region of the illumination light;
- and
- irradiating the illumination light onto a specified point on the substrate at a plurality of positions in the direction within a depth of focus of the projection optical system, based upon the detection positional information during the scanning exposure.
A scanning exposure apparatus which moves a mask and a substrate relative to an energy beam during scanning exposure of the substrate with the energy beam through the mask, comprising:
- a projection optical system disposed on an optical path along which the energy beam passes;
- and
- an illumination optical system disposed on an object plane side of the projection optical system, the illumination optical system distributing the energy beam within a plurality of regions being arranged in a first direction in which the substrate is moved during the scanning exposure and extending in a second direction crossing the first direction in a field of view of the projection optical system.
Dependencies are inferred from the claim text.