WAFER CARRYING APPARATUS

PROBLEM TO BE SOLVED: To provide a wafer carrying apparatus by decreasing the velocity of a flow of an air stream leaked from a gap of a base of an ascending/descending machine so as to suppress the disturbance of the air stream, thereby maintaining a high degree of cleanliness. SOLUTION: The wafer carrying apparatus 100 comprises an enclosure 1 for configuring a clean room; an ascending descending machine base 3' placed in the space of the enclosure 1 with air gaps in every direction, and guided and supported by a guide member of a horizontal driver; and a wafer mount apparatus 4 for mounting a wafer container robot 7 guided and supported by the guide member of an ascending descending driver provided to the ascending descending machine base 3', the wafer carrying apparatus 100 horizontally carrying a robot 7, and freely ascending / descending the robot 7. In the apparatus 100, the ascending descending machine base 3' is provided with a vent hole 3A which satisfies a conditional equation of S1=S2×α×V. S1 is a cross-sectional area of the vent hole in the horizontal direction (m2), S2 is a cross-sectional area of an operating part in the horizontal direction (m2), α is a correction factor (s/m) and defined as (0.27≤α≤0.33), and V is a maximum operating speed of the operating part in the horizontal direction (m/s). COPYRIGHT: (C)2004,JPO