Abstract: A gripper to grip a workpiece includes a body with a flat gripper surface. The gripper surface includes a plurality of openings that are distributed over the gripper surface, each of the openings connectable to a source of suction. At least one flow restrictor is located between the plurality of openings and a connector of the gripper to the source of suction to restrict the inflow through each opening of the plurality of openings. When the suction is applied to the plurality of openings and a part of the workpiece surface covers at least one opening of the plurality of openings and another of the openings remains uncovered, the suction force at the covered opening is sufficiently strong to grip the workpiece surface.

Abstract: A wafer positioning device includes at least one fixed stop that is positioned at a periphery of a clamped position on a surface of a chuck and an extendible finger. A finger extension mechanism extends the finger outward toward a center of the chuck surface, and retracts the finger away from the center of the chuck surface. The finger is configured, when a wafer is placed on the chuck surface and the finger extension mechanism is operated to extend the finger outward, to push the wafer laterally toward the fixed stop until an edge of the wafer contacts the fixed stop when a distal end of the finger is at the periphery of the clamped position.