| 摘要 |
PURPOSE:To make it possible to perform measurement of a stage as a single body, by measuring the cross angle of the stage in the X and Y direction, based on the moving distance in the X direction, the moving distance in the Y direction, which is crossed at a certain angle with the X direction, and the moving distance in the direction different from both the X and Y directions. CONSTITUTION:An X-Y stage 11 is formed by a Y-direction sliding plate 14, which moves in the Y direction by a base table 12 and a driving shaft 13, and an X-direction sliding plate 16, which moves in the X direction by a driving shaft 15. Plane mirrors 171 and 172 are attached to the side surface of the sliding plate 16. A plane mirror 173 is provided uprightly at a position forming an isosceles right triangle with the X and Y directions. The moving distance d1 of the mirror 173, when the sliding plate 16 is moved by x1 in parallel with the mirror 172, is measured by an interferometer 213. The moving distance d2 of the mirror 173, when the sliding plate 14 is moved by y1 in parallel with the mirror 171, is measured by an interferometer 213. The x1 and y1 are measured by interferometer 211 and 212. The degree of orthogonal intersection of X and Y direction of the sliding plate 16 is obtained by using a special expression based on the distances d1, d2, x1, and y1. |
