Method and apparatus for megasonic cleaning with reflected acoustic waves

A method for applying acoustic energy to clean a surface of a substrate, comprising:

• generating acoustic energy oriented in a substantially parallel direction to a surface of a semiconductor substrate from a first transducer;
• altering a direction of the acoustic energy from the first transducer to a substantially perpendicular direction to the surface of the semiconductor substrate;
• and
• generating acoustic energy oriented in the substantially parallel direction to the surface of the semiconductor substrate from a second transducer.

A system for cleaning a semiconductor substrate, comprising:

• a tank having an inner cavity defined by a base and at least one sidewall extending therefrom, the tank capable of retaining a volume of a liquid within the inner cavity;
• a substrate support configured to support and rotate a semiconductor substrate about an axis of the semiconductor substrate as the semiconductor substrate is immersed within the inner cavity of the tank;
• and
• a megasonic transducer coupled to the base, the first megasonic transducer configured to generate acoustic energy toward a reflective surface associated with the base, the reflective surface configured to direct the acoustic energy toward a surface of the semiconductor substrate.