| 摘要 |
PROBLEM TO BE SOLVED: To have a good observation of a stage reference mark so as to have a highly accurate relative alignment of both objects by performing alignment of both objects from the positional information of alignment marks on first and second objects and one or more stepless stage reference marks provided on a drive means. SOLUTION: A reticle alignment mark 1b for base line instrumentation is provided on the surface of a reticle 1 as a first object and a wafer alignment 14 is provided on the surface of a wafer 2 as a second object and a stage reference mark 100 is provided on a stage 21. The stage reference mark 100 shows a structure of a difference in level and the amount of the difference in level is 1/8 of an alignment wave length in the case of a largeσof an illumination system of a microscope and in the case of the smallσis about 1/4 of the wave length. Then, a positional relationship of the reticle 1 and the wafer 2 is found from the positional relationship of the reticle alignment mark 1b and the stage reference mark 10 an the positional relationship of the stage reference mark 100 and the TTL microscope 80. |
