Megasonic cleaning apparatus for fabricating semiconductor device

A megasonic cleaning apparatus for removing contamination particles on a wafer, comprising:

• a piezoelectric transducer for generating megasonic energy;
• an energy transfer rod installed over the wafer along a radial direction of the wafer for distributing the megasonic energy to cleaning solution over the wafer and for vibrating the cleaning solution, wherein the energy transfer rod is shaped and sized to uniformly distribute energy in the radial direction of the wafer through the cleaning solution to remove the contamination particles from the wafer, wherein the energy transfer rod includes a first end and a second end and the diameter of the first end is smaller than that of the second end, wherein the energy transfer rod further includes an elongated front portion and a rear portion tapered to have a larger cross-section diameter than the elongated front portion;
• a vessel for housing the cleaning solution and the wafer, wherein the elongated front portion of the energy transfer rod is located within the vessel;
• and
• a cleaning solution spray nozzle installed over the wafer to spray a cleaning solution between the energy transfer rod and the wafer and a groove formed on the elongated front portion.