| 摘要 |
PURPOSE:To remove restriction in the arrangement of pattern to be used for a TTL alignment as well as to prevent decrease in a throughput by a method wherein an optical element, having a non-axial symmetric convergence or divergent function, is provided in a detection optical system with which the projection image of pattern of the material to be processed is projected by the projection optical system. CONSTITUTION:After a mirror 7 and a cylindrical lens 8 have been provided below a mask 3, a device is constituted in such a manner that the projection image 6 of a pattern 4 obtained by a projection lens 1 and a cylindrical lens 8 is image-picked up by a solid-state image-pickup element (image detecting element) 10 using an objective lens 9. By providing the cylindrical lens 8 between the projection lens 1 and the solid-state image pickup element 10 as above-mentioned, the focussing position of a meridional direction caustic curve 11b can be brought close to the projection lens 1, and a point image 12 can be formed as the point of projection image of a wafer 2. As a result, even when the light of wavelength different from that of exposure is used, an image which will be formed on the same plane in the sagittal direction and the meridional direction can be obtained, and the pattern positions of both sagittal and meridional directions can be detected by one detection field of vision. |
