Intrinsic and H-induced defects at ${\mathrm{S}\mathrm{i}-\mathrm{S}\mathrm{i}\mathrm{O}}_2$ interfaces

Defect reactions pertaining to ${\mathrm{S}\mathrm{i}-\mathrm{S}\mathrm{i}\mathrm{O}}_2$ interfaces are investigated using a first-principles total-energy approach. Interesting results on the atomic structures of interstitial ${\mathrm{H}}^{+}$ and ${\mathrm{OH}}^{\mathrm{-}},$ ${\mathrm{H}}_2\mathrm{O},$ and ${\mathrm{H}}_3{\mathrm{O}}^{+}$ in ${\mathrm{SiO}}_2$ are presented. Three center ${\mathrm{O}–\mathrm{H}}^{+}–\mathrm{O}$ hydrogen bonding is found to play a significant role in the stabilization of all these molecules. The relative stabilities of ${\mathrm{H}}^{+}$ and ${\mathrm{H}}^{\mathrm{-}}$ in Si and ${\mathrm{SiO}}_2,$ H-induced diffusion of oxygen from ${\mathrm{SiO}}_2$ into Si, oxygen vacancy-interstitial pair formation under electron injection conditions, and Si vacancy and interstitial defects in ${\mathrm{SiO}}_2$ are examined.