| 摘要 |
When alignment marks, which have been previously formed on a substrate corresponding to each of two orthogonal axial directions, are detected by a microscope, a main control unit detects positions and numbers of the respective marks, and calculates stretching degrees of the substrate in the two orthogonal axial directions respectively on the basis of information on the detected positions of specified marks and information on designed positions of the specified marks. The main control unit determines a mean value of the stretching degrees by weighting each of the calculated stretching degrees in the two orthogonal axial directions in accordance with the detected numbers of the marks corresponding to each of the two orthogonal axial directions so that the determined weighted mean value of the stretching degrees is set as a magnification correction value. A magnification controller corrects, through a magnification-adjusting mechanism, a magnification of a projection optical system on the basis of the set magnification correction value. When stretching of the substrate takes place, the pattern continuity and the overlay accuracy in an intended privileged direction can be improved. |
