A plating cell adapted for electro-less plating of articles, for example, semiconductor wafers contained in a carrier or "boat", incorporates a megasonic transducer in the plating cell and a rotational drive supporting the wafer carrier in the plating cell. The megasonic transducer applies acoustic energy at megasonic frequencies to the solution in the cell during a plating operation, and the carrier is rotated at a suitable speed, e.g., 45 to 60 r.p.m. A rapid drain is provided to remove the solution from the cell quickly at the end of a plating operation, and a pair of spray tubes with a series of spray nozzles rinses the wafers with de-ionized water. Spargers at the base of the cell inject the plating solution, which proceeds generally upwards in a laminar flow, and spills over a spillway at the top of the plating tank. The spillway comprises a series of triangular teeth which avoid waves or turbulence.