Removal of nanoparticles from a silicon wafer using plasma shockwaves excited with a femtosecond laser

Experiments on the cleaning effect of 100 nm-sized polystyrene latex (PSL) particles on silicon wafers using plasma shockwaves excited via a femtosecond (130 fs) Ti:Sapphire laser (lambda(p) = 790 nm) are reported. By the scan of wafer using the X-Y-Z stage during excited plasma shockwave, the removal variation of nanoparticles on surface was observed in situ before and after plasma shockwave occurred. The cleaning efficiency was strongly dependent on the gap distance between the plasma formation point and the surface. The removal efficiency of the nanoparticles reached 95% without surface damage when the gap distance was 150 mu m. Crown Copyright (C) 2012 Published by Elsevier B.V. All rights reserved.