Abstract
The series model combined with the Weibull distribution is shown to be suitable for characterizing time-dependent dielectric breakdown (TDDB) failures and for projecting the failure rate under normal operating conditions. The validity of existing models for acceleration factors is examined through long-term lifetests with a wide range of stress fields for 11-nm oxides. The resulting curve is found to estimate field acceleration more accurately for lower field regions. The activation energy is also essentially independent of oxide field for thin and near-defect-free oxides.