摘要 |
<p>The relative position between a mask and a wafer is adjusted any time even during an exposure process depending on a displacement of a pattern image due to a change in position of reflectors. Dectectors (13, 14) detect the displacements of reflectors (M1, M2) from their respective reference positions. Based on the dectected displacements, an arithmetic system (15) determines a corrective quantity for at least either a photosensitive substrate (4) or a mask for effectively positioning the photosensitive substrate relative to the pattern image formed out of place. At least either the mask or the photosensitive substrate is moved according to the determined corrective quantity.</p> |