A method for wet treatment of wafers includes a first plate and a second plate substantially parallel to the first plate, and a wafer is held between the first and the second plate substantially parallel. A first dispenser introduces fluid into a first gap between the first plate and the wafer when being treated, and a second dispenser introduces fluid into a second gap between the second plate and the wafer when being treated. At least one vibrating element is acoustically coupled to at least the second plate, and a holder and the second plate are rotated relative to each other about an axis substantially perpendicular to the second plate.