Ultrafine Particle Removal Using Gas Cluster Ion Beam Technology

In this paper, the ultrafine particle removal using CO₂ gas cluster ion beam (GCIB) technology is investigated. The CO₂ GCIB is irradiated the sample at an angle of 0 ^° with respect to the surface normal. The higher particle removal efficiency can be achieved at the higher kinetic energy of the gas cluster, and the inside space of line and space pattern particles can be removed. We also suggested that the CO₂ GCIB process has the high particle removal uniformity without redeposition of the removed particles. It is possible to remove the ultrafine particle as small as 12 nm in diameter (which is required for 2014 by ITRS 2011). The pattern damage is not observed for 45 nm poly-Si pattern. Moreover, the molecular dynamics simulation is performed to investigate the mechanisms of the particle removal by GCIB irradiation.