Effect of Acoustic Cavitation on Dissolved Gases and their Characterization during Megasonic Cleaning

Abstract

In this study, both cleaning performance and pattern damage events were evaluated for specific gases (H2, N2, O2 and Ar) dissolved deionized water (g-DIW) with megasonic (MS). The particle removal ability of all g-DIW with MS was gradually increased with their gasification level risen up. The evaluation of pattern damage was performed on PR line pattern that line width is 300 nm. Results showed a similar trend just like the PRE test. Especially H2 dissolved DI water (H2-DIW) showed the most effective particle removal efficiency (PRE), but it generated lots of damage events than others. In order to clarify the differences of MS cleaning performance as functions of gas types and concentration in g-DIW, the mechanism of bubble nucleation, growth and cavitation effect were theoretically studied with physical properties of dissolved gas under acoustic field. From this result, their relationship with MS could be demonstrated.