Recovery of Quasi-Permanent Bias Temperature Instability in SiC MOSFETs and Its Physical Mechanism

Bias temperature instability (BTI) is one of the key reliability issues for silicon carbide (SiC) metal–oxide–semiconductor-field-effect transistors (MOSFETs). Currently, research on BTI mainly focuses on threshold voltage drifts under static and dynamic gate stress, but the recovery behavior of threshold voltage needs to be further explored. In this article, the recovery effect of short-circuit (SC) stress on BTI and the recovery mechanism are investigated systematically. It is found that both positive and negative BTI (PBTI and NBTI) could recover under non-destructive SC stress, and the larger SC energy, the stronger BTI recovery ability. Moreover, recovery with larger SC energy would exacerbate the threshold voltage drift under strong gate electric field. However, under normal gate stress, the recovered threshold voltage does not drift more. These findings not only help to understand BTI recovery mechanism, but also provide a viable approach for suppressing BTI in power electronics applications.