Reliability factors of ultrathin dielectric films based on highly controlled SiO2 films

Two main factors determine the reliability of ultrathin SiO2 films thermally grown on Si when subjected to long-term electrical stress. One of them is two-dimensional thickness uniformity for suppressing the decrease in Weibull slope. The other is film density distribution, which affects the degradation rate during application of high electric stress. The importance of thermal process optimization in inhibiting density fluctuation is demonstrated.