Low power megasonics is of interest to semiconductor cleaning community due to minimal feature damage. In this work, megasonic field at low power density in conjunction with electrochemistry is used for enhanced removal of silica particles from tantalum wafers. Cleaning studies were conducted in air or argon saturated aqueous solutions at 0.5W/cm2 in the absence and presence of applied potentials of -1.5 V or -2.0 V to tantalum (vs Ag/AgCl). The improvement in particle removal efficiency is attributed to oscillating hydrogen bubbles formed from water reduction in vicinity of tantalum surface and grown to a resonant size under suitable acoustic conditions.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Electrical and Electronic Engineering