| 摘要 |
<p>PURPOSE:To prevent any dust from adhering to a wafer held by a chuck mechanism by providing an injecting mechanism on a x-y plane positioning stage, the mechanism preparing an air jet for isolating the wafer from the surroundings. CONSTITUTION:A wafer 1 is held by a chuck mechanism 12, and coarsely positioned in the x direction by a track base 20, etc., and in the y direction by a track base 25, etc., and further finely positioned by a fine positioning mechanism 17. The stage of a positioning stage is detected by the rotation of a position detector and a ball screw 8. An air stream without dust is injected from a group of air nozzles 18 around the wafer 1 from the side of the chuck mechanism 12, and the upper part of the wafer 1 can be isolated from the surroundings of the wafer 1 by an injected air stream 19. Hereby, a dust 3 from the surroundings of the wafer 1 is prevented from going around the upper part of the wafer 1 to be further prevented the dust from sticking to the upper part of the wafer 1.</p> |
