Comparison of E and 1/E TDDB models for SiO/sub 2/ under long-term/low-field test conditions

A low-field three-year TDDB study was undertaken to clearly understand which TDDB model, E or 1/E, describes the observed time-to-failure data better. The results are unambiguous and strongly suggest that the physics of failure is described much better by the E-model. This has important design-limit implications for thin gate oxides relative to the maximum electric field which can be allowed for reliable operation.