| 摘要 |
PURPOSE:To make it possible to use an aligner at the focal point which has been most stabilized and hence improve focussing accuracy by performing blind exposure processing prior to actual exposure processing and opening and closing a first shutter, performing the blind exposure processing at the interval identical to the on/off interval required when performing the actual exposure processing. CONSTITUTION:Under the condition where a first shutter 7 is open, an attempt is made to irradiate exposure light from an exposure light source 6 in the same way required for an actual exposure process and raise the temperature of an aligner, particularly the temperature of an exposure optical system 2 near the temperature prevailing during actual exposure process. A further attempt is made to open and close a first shutter 7 at an interval equivalent to an on/off exposure interval required during actual exposure process, which increases the temperature of the aligner, particularly the optical system 2 to the temperature prevailing during the actual exposure process and maintains the temperature so that actual exposure process may be carried out from a constant focal point which has been stabilized. It is, therefore, possible to obtain stabilized exposure accuracy. |
