| 摘要 |
<p>PURPOSE:To eliminate unstable support of a wafer by a centrifugal force generated when a mechanical type chuck is rotated. CONSTITUTION:A slide supporting material 1 is formed in a rectangular plate state, a pawl 1a for holding a peripheral edge of a wafer 4 protrudes from one end of an upper surface, a first weight member 1b is provided at one end of a lower surface opposed to the pawl 1a, and a second weight member 1c is so provided at the other end as to be equilibrated with the member 1b. The material 1 is slidably supported to at least three sliding grooves 2a equally divided on a circumference. Eccentric means 3 is installed between the member 1b and a peripheral wall of a rotary shaft 2, and bellows elongated or contracted by flowing or discharging of pressure gas 5 are used. When the means 3 is moved forward, a center of the material 1 coincides with an axial center of the shaft 2, while when it is moved rearward, it is deviated.</p> |
