| 摘要 |
When both a wafer transfer means in a first transfer device and a wafer transfer means in a second transfer device move downward at the same time, the amount of exhaust air by an exhaust fan is increased by the control of a control section, whereby the down flow of clean air is intensified. Turbulence of air flow caused when both the wafer transfer means in the first transfer device and the wafer transfer means in the second transfer device move downward at the same time is absorbed by the down flow intensified as described above. |
