| 摘要 |
PURPOSE:To eliminate position discrepancy caused by delivery of a wafer by a method wherein a wafer put and fixed on an X-Y table which is enabled in reciprocal movement precisely and moved from the prealignment position to the precision alignment position with the X-Y table. CONSTITUTION:An upper stage 7b of an X-Y table 7 is enabled fine movement against a lower stage 7a precisely to the axial directions of X-X' and Y-Y'. A guide means and a driving means are provided to give the lower stage 7a reciprocal movement by a certain distance horizontally as shown by a double- directional arrow B-B'. Three-point rollers 2a-2c and a positioning roller 3 are provided on the X-Y table 7 for prealignment of the wafer 1. With this constitution, as it is not necessary for the wafer 1 to be attracted and held, surface contamination of the wafer 1 is avoided and, as such processes as attracting and holding transport delivery are not included, position discrepancy caused by transport and delivery is eliminated. |
