| 摘要 |
PROBLEM TO BE SOLVED: To cut down the base line measuring time of a plurality of alignment sensors. SOLUTION: The first reticule is loaded to acquire the central position of reticule pattern, simultaneously acquires the detection center of the first alignment sensor to find out the base line quantity B11 from the pattern center to the detection center. Next, the base line quantity B21 of the second alignment sensor to count the differenceΔB(=B21 -B11 ) of the base line quantity (step 104). As for the reticules after the second alignment sensors, the base line quantity B12 of the first alignment sensor is found out by the same procedures to count out the base line quantity B22 of the second alignment sensor by the formula of B22 =B21 +ΔB (step 109) so that the fine alignment may be performed to expose the reticule patterns to respective shot regions (step 110, 111).
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