Abstract: A conveying arm for conveying a substrate while holding it with suction pads has, on the side of the conveying arm from which the suction pads extend, elastic members, such as flat springs, which are shorter than the suction pads. The flat springs are located above the tip ends of the suction pads when they hold the substrate and when the substrate is lowered to the work stage, the flat springs press any bent portions of the substrate down toward the work stage, which leads to flattening of surface of the substrate against the work stage so as to eliminate leakage of vacuum, used for suctioning the substrate against the work stage, from peripheral portions of the substrate. As a result, the substrate can be securely held on the work stage.