It had been shown that thermodynamic and kinetic driving forces existed for an isolated O defect to segregate to Si/HfO2 interfaces. Using first-principles calculations, it was shown here that the accumulation of multiple point defects (O vacancies and interstitials) at Si/HfO2 interfaces was also thermodynamically favored and that this preference was relatively insensitive to the areal density of interfacial defects. These results indicated that the O point defect chemistry could provide a rationale for the formation of interfacial phases.

Oxygen Defect Accumulation at Si:HfO2 Interfaces. C.Tang, R.Ramprasad: Applied Physics Letters, 2008, 92[18], 182908