| 摘要 |
PROBLEM TO BE SOLVED: To suppress the deterioration of the overlay accuracy of an exposure method, by using a mask wherein the patterns formed correspondingly to a common periodicity are provided, and by performing the exposure of a substrate repeatedly under the same illumination condition while moving the mask and the exposed substrate relatively to each other. SOLUTION: A wafer put on a wafer stage is set in a predetermined position relatively to a mask. The position of the wafer is sensed by moving an xy-position sensing mechanism of the wafer stage through its control unit. On the wafer stage, the wafer is moved without its exposure from a center point A of a pattern to a point B shifted left or right from the center point A. Subsequently, the exposure of the wafer is performed by an exposure amount for obtaining a pillar-form pattern having a predetermined dimension. Thereafter, by moving the wafer stage left or right, the exposure of the wafer is performed again by the same exposure amount. As repeating this operation, the wafer is moved to a point C of the pattern, and this movement distance is made not larger than one-hundredth of a whole movement distance to reduce a roughness generated in the edge portion of a resist. As a result, the deterioration of the image quality of the pattern can be prevented as satisfying the dimension controllability and focal depth of an exposure method.
|
