MEGASONIC RESONATOR FOR WASHING DISK AND METHOD FOR USING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide an improved method and an improved apparatus for performing the megasonic washing of a wafer. SOLUTION: A megasonic washing apparatus has at least one reflector and is arranged so as to gather washing energy apt to be used wastefully to turn the direction of the washing energy to one or a plurality of positions of a wafer. In a certain embodiment, this washing apparatus includes a composite parabolic reflector 51. This parabolic reflector has desirable length larger than the width of the wafer and almost equal to the diameter of the wafer and provides a focal point changed along the length of the parabolic reflector. The energy applied to the reflector at different points 54-59 along the length of the reflector is turned toward a plurality of different points 84-89 along the edge of the wafer.