Secondary ion emission from silicon and silicon oxide

Abstract

The emission of Si +, Si 2+, Si 3+, Si 2 +, SiO + and B + from boron doped silicon has been studied at oxygen partial pressures between 2 × 10 −10 and 2 × 10 −5 Torr. Sputtering was done with 2 to 15 keV argon ions at current densities between 3 and 40 μ A cm 2 . The relative importance of the different ionization processes could be deduced from a detailed study of the yield variation at varying bombardment conditions. Comparison with secondary ion emission from silicon dioxide allows a rough determination of the composition of oxygen saturated silicon surfaces.