Core-level photoemission and the structure of the Si/SiO2 interface: A reappraisal

Photoemission spectroscopy of spherosiloxane cluster derived Si/SiOx interfaces has allowed the direct assignment of observed spectral features to specific chemical moieties. The implications of these assignments for structural models of the Si/SiO2 interface are explored. Models specifically constructed to be consistent with photoemission data are shown to be incorrect after reanalysis of core-level shifts based on the recently synthesized model systems. A new model for the Si/SiO2 interface is proposed which is consistent with the current understanding of photoemission for Si/SiOx interfaces as well as with results from numerous other experiments.