Exposure method, exposure apparatus, and mask

An exposure method comprising:

• (a) forming a first layer exposure pattern having a first plurality of unit patterns on a photosensitive substrate and connecting the first plurality of unit patterns through at least one first layer stitching portion;
• (b) forming a second layer exposure pattern having a second plurality of unit patterns on the photosensitive substrate overlaying the first layer exposure pattern and connecting the second plurality of unit patterns through at least one second layer stitching portion;
• and
• (c) smoothing a contrast between the second plurality of unit patterns overlaying the first plurality of unit patterns.

An exposure apparatus for forming a first layer and a second layer on a photosensitive substrate, the exposure apparatus comprising:

• an illumination optical system illuminating a mask with luminous flux emitted from a light source, a plurality of divided patterns being formed on the mask through stitching portions wherein a stitching portion in the first layer is disposed offset from a stitching portion in the second layer;
• a blind disposed in an optical path of the luminous flux, the blind changing a dimension of an illumination area on the mask illuminated by the illumination optical system;
• a projection lens system disposed in the optical path on a side of the mask opposite from the illumination optical system, the projection lens system projecting the luminous flux having passed through the mask onto the photosensitive substrate;
• and
• a controller communicating with the blind to control a position of the blind in accordance with the divided patterns.

An exposure method comprising the steps of:

• projecting a portion of a first pattern into one of a plurality of first projection areas on a photosensitive substrate, the first projection areas being separate from each other with adjacent projection areas overlapping each other by a predetermined overlap amount in a direction perpendicular to a scanning direction of the substrate;
• synchronously scanning the first pattern and the substrate in the scanning direction relative to the plurality of first projection areas to transfer the first pattern onto the substrate;
• projecting a portion of a second pattern into a plurality of second projection areas disposed offset from the plurality of first projection areas in the direction perpendicular to the scanning direction by a predetermined distance within a plane defined by the substrate;
• and
• synchronously scanning the second pattern and the substrate in the scanning direction relative to the plurality of second projection areas to transfer the second pattern onto the substrate.