Patent ID: 7412982

Claim:
A megasonic cleaning apparatus comprising: a cleaning vessel; a rotation table located in the cleaning vessel and adapted to support a wafer placed on the rotation table; a rotation axis connected to a bottom of the rotation table; a motor connected to the rotation axis and configured to rotate the rotation table; a cleaning probe located over the rotation table and the wafer and configured to transmit megasonic waves to a surface of the wafer via a cleaning fluid on the surface of the wafer; a piezoelectric transducer connected to the cleaning probe and configured to generate megasonic waves; and, a cleaning fluid supplying tube configured to supply cleaning fluid onto the wafer, wherein the cleaning probe comprises a rear portion connected to the piezoelectric transducer, a front portion located opposite the rear portion and located over the wafer, and a protrusion located between the rear portion and the front portion, and located over an edge portion of the wafer, wherein a cross section width of the protrusion is larger than a cross section width of the front portion.