| 摘要 |
PROBLEM TO BE SOLVED: To avoid the need to relate the origins of apparatuses which measure heights of substrates or masks on a plurality of stations in a lithographic projection apparatus having a plurality of substrate tables or mask tables. SOLUTION: A substrate W is mounted on a substrate table WT; then, vertical positions of a physical reference surface and vertical positions Z<SB>LS</SB>of the substrate surface are measured at a plurality of points on a measurement station (at the right of figure 8) using a level sensor 10; simultaneously, vertical positions Z<SB>IF</SB>of the substrate table are measured at the same points using a Z-interferometer Z<SB>IF</SB>; and the substrate surface height, Z<SB>Wafer</SB>=Z<SB>LS</SB>+Z<SB>IF</SB>, is mapped. Then, the substrate table carrying the substrate is moved to an exposure station (to the left of figure 8) and vertical positions of the physical reference surface is again determined. Then, when the substrate is positioned at a right vertical position during the exposure process, the height map is referenced. This process can be applied to a mask. COPYRIGHT: (C)2008,JPO&INPIT
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