A wafer scrubber is disclosed, including a chamber, and a holder connecting to a spindle disposed in the chamber, wherein the holder supports a wafer, and the wafer spins to remove water on the wafer, and a mashed inner cup comprising a plurality of through holes disposed between the holder and a wall of the chamber, wherein the mashed inner cup receives water from a surface of the wafer and rotates around the spindle to release the water through the through holes.