| 摘要 |
<p>Pattern transfer is performed with an exposure precision which is improved by the reduction of contamination such as adhesion of photosensitive agent, etc. to the optical member of a projection system, etc. After the optical member (OB) at a predetermined position is cleaned by a cleaner (8) while transfer is not performed, or while air is made to flow between a wafer (W) and the optical member (OB) by a contamination preventive device (98), a pattern is transferred to the wafer (W). Further, while transfer is not performed, the contamination of the optical member (OB) at a predetermined position is measured by a contamination measuring instrument (84) and, in accordance with the measurement result, transfer or cleaning or replacement of the optical member (OB) is performed.</p> |
