Effects of He and Ar ion kinetic energies in protection of organosilicate glass from O₂ plasma damage

In-situ x-ray photoelectron spectroscopy (XPS) and ex-situ Fourier transform infrared studies of He plasma and Ar⁺ ion bombardment pretreatments of organosilicate glass demonstrate that such pretreatments inhibit subsequent O₂ plasma-induced carbon loss by forming a SiO₂-like damaged overlayer, and that the degree of protection correlates directly with increased ion kinetic energies, but not with the thickness of the SiO₂ overlayer. This thickness is observed by XPS to be roughly constant and <1 nm regardless of ion energies involved. The data indicate that ion kinetic energies are an important parameter in protective noble gas plasma pretreatments to inhibit O₂ plasma-induced carbon loss.