| 摘要 |
PURPOSE:To stabilize a vertical movement of a wafer mounting base by flattening the lower projection portion of a pin fixing portion and a facing surface of a pushing portion member and making a spring for supporting the wafer mounting base into conical form. CONSTITUTION:A wafer mounting base 33 is installed at an opening formed in the center of the lower electrode 31. Pins 35 and 36 on a pin fixing board 34 are made movable through holes 37 and 38. A conical spring 40 is installed between a concave 39 of the pin fixing board 34 and a ceiling of the wafer mounting base 33. A push board 44 is disposed facing a projected portion 34a under a pin fixing board 14. The surface of the push board 44 is flattened in accordance with the shape of the under surface of the projected portion 34a. The push board 44 is connected to an air cylinder 45 and the pins 35 and 36 are projected onto the wafer mounting base 33 when the cylinder 45 drives. According to such a construction, a vertical movement can be performed smoothly and a wafer transportation is assured. |
