JP2862754B

A cleaning apparatus for cleaning a semiconductor wafer comprises a spin chuck having a turn table. A gas supplying passage is formed in a shaft for supporting the turn table to supply a protecting gas to the rear surface of the wafer. A conical movable member, arranged to cover an end off the shaft, is movable upward and downward in accordance with the flow off the protecting gas supplied thereto. Inner ends of three reciprocating arms, supported by the turn table and extending in radial directions, abut against an outer surface of the movable member and biased by springs. Fixed pins are arranged on the turn table at positions which divide the circumference of the turn table into three equal parts, along the edge of the wafer. Three swingable levers are arranged such that one is provided between two adjacent fixed pins. One end of each swingable lever is connected to the outer end of each reciprocating arm and the other end of the lever has a pin brought into contact with the edge of the wafer. When the protecting gas is supplied, the movable member is moved upward to a working position, and the reciprocating arms are pressed by the movable member and moved outward. As a result, the swingable levers are moved so as to bring their pins into contact with the edge of the wafer, thereby clamping the wafer among the pins.