| 摘要 |
A Bernoulli pick-up tool (10) comprises a head member (11) having a flat major surface (18) and an air passage (16) perpendicular to the major surface and extending through the center of the head member for directing gas at a sufficient velocity to permit a wafer (15) having a flat surface (19) parallel to the major surface of the head and generally centered on the air passage to be suspended in close proximity to the major surface. According to the known Bernoulli principle, the velocity difference of gas flowing along the two surfaces of the wafer creates a pressure differential which permits the wafer to be suspended against the force of gravity. In accordance with the invention, the holding action of the pick-up tool is stabilized by including a cavity (17) in the head member which surrounds the air passage (16). Also, a plurality of elements (23) extend from the periphery of the head member, each adapted to bear against only the periphery of the wafer. The contact surface (25) of these elements is at an angle with respect to the wafer so as to minimize physical contact with the wafer.
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