Wafer rotary holding apparatus and wafer surface treatment apparatus with waste liquid recovery mechanism

A wafer rotary holding apparatus comprising:

• rotating means for rotating a wafer, the rotating means having an upper surface with a centrally formed through hole;
• resting means for resting the wafer, the resting means being mounted on an upper surface of the rotating means, wherein a gap is formed between a bottom surface of a resting wafer and the upper surface of the rotating means;
• and
• holding means for holding the wafer onto the resting means, said holding means comprising pressure reducing means for reducing a pressure along a fluid flow path when a centrifugal force is generated by a rotation of the rotating means,
• wherein reducing the pressure results in a suction of fluid through the through hole and draws fluid from a lower surface of the rotating means to the upper surface of the rotating means and onto a bottom surface of the wafer, and
• wherein reducing the pressure also draws the wafer downward to fastly hold the wafer onto the resting means, and drawn fluid is outwardly discharged in a continuous manner.