Particle Removal from Micrometer-Sized Trenches Using High-Velocity-Aerosol Cleaning and Comparison with Megasonic Tank Cleaning

Cleaning technologies employing physical forces (such as megasonic and high-velocity-aerosol cleaning) are usually evaluated by comparing the particle removal efficiency on blanket wafers with damage formation on fragile structures, typically gate stack type structures. However patterned wafers provide a much more realistic cleaning challenge. Particle removal efficiencies from trenches in micrometer dimension have been evaluated using high-velocity-aerosol cleaning. When using short cleaning times, a large decrease in cleaning efficiency is found for even modest pattern dimension. By extending the cleaning time, cleaning efficiencies comparable to blanket-wafer tests can be reached. Moreover, batch megasonic cleaning shows a similar decrease in performance as high-velocity-aerosol cleaning.