Oxygen defect accumulation at Si:HfO2 interfaces

It has been shown earlier that thermodynamic and kinetic driving forces exist for an isolated oxygen defect to segregate to Si:HfO2 interfaces. In the present work, using the first principles calculations, we show that the accumulation of multiple point defects (O vacancies and interstitials) at Si: HfO2 interfaces is also thermodynamically favored and this preference is relatively insensitive to the areal density of interfacial defects. These results indicate that the O point defect chemistry pan provide a rationale for the formation of interfacial phases. (C) 2008 American Institute of Physics.