A Theoretical Evaluation of Megasonic Cleaning for Submicron Particles

Abstract

The physics of megasonic cleaning is investigated. A novel particle removal mechanism is analyzed, and the relevant quantities are evaluated. It is shown that the megasonic removal force scales as the cube of the particle diameter, and that megasonic cleaning technology cannot remove particles of 0.1 μm and smaller. Therefore, megasonic cleaning is unlikely to be a viable technology for manufacturing devices whose linewidth is below 0.35 μm.