GHz AC to DC TDDB Modeling with Defect Accumulation Efficiency Model

Abstract

In this work, AC time-dependent dielectric breakdown (TDDB) of SOI MOSFETs was systematically investigated with considerable experimental data using various stress patterns. It is confirmed that both the time to breakdown $(\mathrm{T}_{\text{BD}})$ and hardness of post-breakdown could be improved at GHz frequency. Based on frequency dependence of TDDB lifetime, we propose a comprehensive defect accumulation efficiency $(\xi)$ model related to pulse width, helping to predict AC TDDB lifetime. In addition, new failure mechanisms for on-state TDDB are clarified by weakening HCI coupled effect. This study is significant for lifetime estimation of logic devices under dynamic circuit operations.