Surface oxidation of Si assisted by irradiation with large gas cluster ion beam in an oxygen atmosphere

Surface oxidation of Si assisted by Ar cluster impact with a current density of a few μA/cm 2 under O 2 atmosphere was investigated. Thin-film formation by cluster ion beam presents a number of advantages such as atomic-scale surface smoothing, high density and precise stoichiometry. We used an Ar cluster ion beam with 20 keV and a mean size of 1000 atoms per cluster and measured the emission yields of Si + and SiO + after Ar cluster ion irradiation in O 2 atmosphere using a quadrupole mass spectrometer to investigate the dependence of Si surface oxidation on oxygen partial pressure. It was found that the Si surface was oxidized by Ar cluster ion irradiation in O 2 atmosphere.