| 摘要 |
PROBLEM TO BE SOLVED: To hold and carry a wafer stably regardless of the posture of the wafter by catching the wafer and carrying it while holding it without contact by a pair of fluid jetting means. SOLUTION: Air A supplied from a compressor 17a is jetted at flow rates of Qa and Qb toward the obverse and reverse 8a and 8b of a wafer from nozzles 16e and 16f, through flow control valves 19a and 19b, and upper and lower arm ducts 16a and 16b. The air A flows radiately in radial direction from the center of the obverse and reverse 8a and 8b of the wafter 8. At this time, from a range sensor 20, distance data D are outputted to a controller 21. Now, in case that the distance d from the range sensor 20 to the surface 8a of the wafer 8 is smaller than the reference distance d0, the controller 21 outputs a flow control signal S to the flow controller 19a so as to increase the flow rate Qa. Since the wafer 8 is retained by the fluid pressure and the friction pressure working in vertical direction and horizontal direction, it can be carried while being retained stably without being influenced by the posture of the wafer 8. |
