| 摘要 |
<p>PURPOSE:To provide a wafer stage device which firmly supports a wafer while correcting its flatness if is warped. CONSTITUTION:A stage 11 has through holes 13 connected via a vacuum lines 14 to a vacuum pump 15. Solenoid valves 16a to 16g are provided in vacuum lines 14, and the timing of opening of each of the electromagnetic valves 16a to 16g is controlled by a control 17 depending upon the warpage of a wafer. Consequently, the stage can support a wafer in a flat state by suction even if it is warped.</p> |
