Patent ID: 7586235

Claim:
An apparatus for processing a wafer, comprising: a bracket for positioning and rotating the wafer about an axis; a platter aligned beneath and parallel to the bracket, with the platter having a through hole, and the wafer having a first side facing the platter and a second side facing away from the platter; a first fluid source connected to the through hole for flowing a first chemical within a gap between the first side of the wafer and the platter; a second fluid source for flowing a second chemical onto the second side of the wafer; at least one acoustic-wave transducer, positioned on the platter, capable of converting AC power signals into acoustic energy to be transmitted into the first and second chemicals, the at least one acoustic-wave transducer having a load impedance magnitude and a load impedance phase; an RF power source, including an RF generator to produce the AC signals and a transmission line to transmit them to the at least one acoustic-wave transducer, the RF power source having a source impedance magnitude and a source impedance phase; and a matching circuit connected to the RF power source and the at least one acoustic-wave transducer, to match the load impedance magnitude and load impedance phase to the source impedance magnitude and the source impedance phase.