| 摘要 |
PURPOSE:To alleviate influence of a foreign matter of a rear surface of a board to a flatness, etc., by forming a contact part at the time of sucking conveying/ delivering arms and a sucking surface of a wafer holder at different positions and shapes in the rear surface of the board. CONSTITUTION:When a wafer 1 is placed on conveying/delivering arms 8, it is brought into contact with outer peripheries of wafer sucking parts 81-83, vacuum evacuated at inside and held. In this case, an area on broken lines of contact areas 81a-83a of the arm 8 with a rear surface of the wafer 1 are so set as to be different from those of contact areas 51-60 of the holder with the rear surface of the wafer 1. Thus, since dust generation due to contact of the arm 8 with the wafer is not brought into contact with the holder, a foreign matter is not interposed between the wafer 1 and the holder, and hence a flatness of the surface of the wafer is held. |
