Secondary ion and sputtered neutral formation from oxygen loaded Si(100)

We have studied the problem of quantification of secondary ion yields from oxygen covered Si(100) using secondary ion mass spectrometry (SIMS), secondary neutral mass spectrometry (SNMS) with electron impact postionization, Auger electron spectroscopy (AES), and photoelectron spectroscopy (XPS). Implantation of oxygen does not lead to detectable amounts of SiO₂, whereas exposure to gas phase O₂ during Ar⁺ or O⁺₂ ion bombardment leads to a closed SiO₂ layer. The surface chemical state evaluated from the secondary ion fragmentation distributions exhibits only minor changes between the pure implantation and the additional gas‐phase adsorption case. It is proposed that the secondary ion emission of the Si–O system is influenced by a ‘‘first‐order’’ effect of collision‐induced SiO₂ formation during the individual sputtering event.