Interplay of voltage and temperature acceleration of oxide breakdown for ultra-thin oxides
In this work, we unequivocally demonstrate that strong temperature dependence of time(charge)-to-breakdown TBD/QBD observed on ultra-thin oxides is not a thickness effect but rather a consequence of two experimental facts: (1) voltage-dependent voltage acceleration and (2) temperature-independent voltage acceleration within a fixed TBD window. By extending down to ?30C, we found non-Arrhenius temperature dependence is a totally independent effect. Based on our statistically accurate experimental database, we found that defect-generation rate and critical defect density as commonly measured using stress-induced leakage current (SILC) only show a change of two orders of magnitude and no change, respectively. Weibull slopes are also found to be temperature-independent. We propose an alternative model of two-step hydrogen degradation to explain these experimental results.
oxide breakdown ultra-thin oxide reliability gate dielectric tddb