First-Principles Calculations of Defects in Oxygen-Deficient Silica Exposed to Hydrogen

Hydrogen-related defects and oxygen vacancies in silica are analyzed using first-principles density functional calculations. Energetics, structures, charge-state levels, and hyperfine parameters are determined. These calculations identify the hydrogen bridge related to the E'(4) center as the defect responsible for the stress-induced leakage current, a forerunner of dielectric breakdown of gate oxides in transistors.