Abstract
In this paper, the evaluation methods of the degradation and dielectric breakdown of ultrathin SiO2 thermally grown on Si, which are one of most superior dielectric films, are introduced along with some examples. SISuR (Stress-Induced oxide Surface Roughness) method with using a reaction between SiO2 films with trapped charges and etching solution is available to clarify that the degradation in SiO2 film under high electric field stress is not uniform. Furthermore, it is indicated that thermal oxidation of the atomically-flat Si terrace surface does not progress two-dimensionally uniformly, strictly speaking. The non-uniform oxidation is one of the origins of the wide lifetime distribution of dielectric breakdown of the ultrathin SiO2 films.
