| 摘要 |
PROBLEM TO BE SOLVED: To provide a method and apparatus for adjusting a focus position which is capable of increasing a measurement accuracy by canceling the deviation of a focus among a plurality of regions on a wafer in which an overlay accuracy between a resist pattern after exposure and a pattern on a base substrate is measured. SOLUTION: This method for adjusting a focus position includes a first and a second focus position adjustment process. In the first process, laser beam LB from a source 5 of laser beam is cast on the surface of a wafer W and laser beam reflected from the wafer is received by a photo detecting section 7 through a slit 6 and then a provisional focus position on the wafer is set based on the luminance of the received light. In the second process, a plurality of measurement marks provided on the wafer are picked up for their images by an image pick-up device 8 and are scanned with light to obtain their pictures, the obtained pictures are compared with template pictures obtained by scanning the measurement marks at a proper focus position of the wafer by means of a calculating section 9, and the position of the wafer W is set by a controller 11 to such a one that both the pictures are coincident most. |
