| 摘要 |
PURPOSE:To prevent an increase in the area of an installed floor due to an extension in the vertical direction by vertically lifting and dropping a cassette base plate, on which cassettes are stacked vertically and placed, and providing a means delivering the wafer in a lowermost section and a means detecting the presence of the cassettes. CONSTITUTION:Wafer supply cassettes 24, 25 in which the wafers are encased are set to a wafer supply section, and empty encasing cassettes 43, 44 are set to a wafer encasing section. The presence of the wafers is made sure by light- emitting and -receiving type photosensors 49, 50 when an optical axis 51 is interrupted by the wafer at a lowermost stage. When a solenoid valve 52 is opened and a wafer detecting means 34 is supplied with air pressure, the wafer 53 at the lowermost stage is floated and carried, and placed on the belt of a loader section 22 and fed to a treating device proper 21. The cassette base plate 31 is dropped only by a section corresponding to a pitch of the wafer receiving groove of the cassette by a cassette lifting means 36, and the wafers are fed to treating device 21 one by one in succession. |
