Exposure method and projection exposure apparatus

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 rectangular 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 apparatus in which a substrate is exposed with an energy beam by moving a mask and the substrate relative to the energy beam, comprising:

• a projection system, arranged in a path of the energy beam, which is a reduction system to project a reduction image of a pattern formed on the mask onto the substrate;
• an illumination system, disposed along the path of the energy beam, which distributes the energy beam within a specified rectangular region in an image field of the projection system;
• a first stage, disposed on an object surface side of the projection system, which is movable in a first direction while holding the mask during scanning exposure of the substrate;
• a first interferometer which measures positional information of the first stage in the first direction during the scanning exposure;
• a second stage, disposed on an image surface side of the projection system, which is movable in a second direction while holding the substrate during the scanning exposure, wherein a width of the specified region in the second direction is shorter than a length of the specified region in a direction perpendicular to the second direction;
• a second interferometer which measures positional information of the second stage in the second direction during the scanning exposure;
• a driving unit connected to the first and second interferometers to adjust a relative relationship between the mask and the substrate based on the positional information measured by the first and second interferometers during the scanning exposure, said driving unit including a first driving system to move the first stage and a second driving system to move the second stage, wherein the first stage is moved at a first speed and the second stage is moved at a second speed which is different from the first speed and a ratio between the first speed and the second speed is determined in accordance with a reduction magnification of the projection system;
• and
• a reflection member, disposed in the path of the energy beam within the illumination system, which reflects the energy beam, wherein the second direction is substantially parallel to a plane which includes an axis of the energy beam incident on the reflection member and an axis of the energy beam reflected by the reflection member.

A scanning exposure method in which a substrate is exposed with an energy beam by moving a mask and the substrate relative to the energy beam, comprising:

• providing the mask on a first stage;
• providing the substrate on a second stage;
• moving the first stage in a first direction during scanning exposure;
• moving the second stage in a second direction during the scanning exposure, wherein the first stage and the second stage are moved at respective speeds which are different from each other, and the respective speeds are determined in accordance with a reduction magnification of a projection system that projects a reduction image of a pattern formed on the mask onto the substrate;
• distributing the energy beam within a specified rectangular region in an image field of the projection system through a reflection member of an illumination system, wherein a width of the specified region in the second direction is shorter than a length of the specified region in a direction perpendicular to the second direction, and wherein the second direction is substantially parallel to a plane which includes an axis of the energy beam incident on the reflection member and an axis of the energy beam reflected by the reflection member;
• measuring, during the scanning exposure, positional information in the first direction and rotational information of the first stage using a first interferometer;
• measuring, during the scanning exposure, positional information in the second direction of the second stage using a second interferometer;
• and
• adjusting, during the scanning exposure, a positional relationship between the mask held on the first stage and the substrate held on the second stage based on the positional information and the rotational information measured by the first interferometer and the positional information measured by the second interferometer.