Valence-alternation-pair model for interface states, fixed oxide charges, radiation defects, and impurities of the Si-SiO₂interface

The valence-alternation-pair model for non-crystalline SiO 2 and its application to various defect properties of this material are briefly reviewed. It is shown that this model, which assumes the existence of pairs of over- and under-coordinated oxygen atoms, enables a consistent explanation of the origin and nature of interface states, fixed oxide charges, and radiation defects of the microelectronic Si-SiO 2 interface and an interpretation of the role of its most important impurities, i.e. hydrogen and sodium.