EVALUATION OF CHARGING EFFECTS DURING X-RAY PHOTOELECTRON SPECTROSCOPY MEASUREMENTS OF ULTRA-THIN SiO_2/Si INTERFACES

摘要

The binding energy of the Si~(4+) component of the Si 2p core-level peak and the single O 1s core-level peak observed for the SiO-2/Si system exhibit energy shifts towards higher energies as the oxide thickness is increased. The Si~0,. Si~(1+), and Si~(3+) components of the Si 2p core-level peak also exhibit a shift to higher energies but the values are much small as compared to that of Si~(4+) and O 1s. The identical energy shift for Si~(4+) and O 1s is a clear indication of x-ray induced charging effect of SiO_2 as compared to the small charging effect induced in the substrate. The similar shift for Si~(1+) and Si~(3+) components and the Si~0 component arising from the bulk Si has been explained by the interface structure.