| 摘要 |
PURPOSE:To enable proper vacuum absorption of even a brittle material, by a method wherein a vacuum pipe is formed by a shape memory material, the heat dissipation speed of the vacuum pipe is controlled through a change in an amount of draft in the vacuum pipe, and the vacuum pipe is deformed according to heat dissipation. CONSTITUTION:A vacuum pipe 10 is heated through energization of an electric wire 11, and the vacuum pipe 10, extended through the force of a compression coil spring 17, is restored to a zigzag condition through the effect of a shape memory alloy. After a moving base 3 is lowered, energization to the electric wire 11 is shut off, a vacuum pump is driven, and an electromagnetic valve 9 is opened, and this causes suction of air through absorbing pads 13. In which case, the vacuum pipe 10 is cooled, and simultaneously, a slide plate 12 is lowered through the force of the spring 17. When a gap Z between the under surfaces of the absorbing pads 13 and the upper surface of wafer 1 is brought to zero, suction of air is stopped and cooling of the vacuum pipe 10 is stopped. This causes down extension of the vacuum pipe 10 to be balanced with the reaction force of the spring 17, and absorption of the wafer 1 is completed.
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