Opportunity to achieve an efficient SiC/SiO2 interface N passivation by tuning the simultaneous oxidation modes during the SiC surface nitridation in N2 + O2 annealing

Abstract

We investigated a possible guideline to design the SiC surface nitridation process for an efficient interface N passivation in high-temperature N2 + O2 annealing, based on the understandings of SiC surface nitridation kinetics. Based on the findings of the time-dependent transition of the simultaneous SiC surface oxidation mode from passive to active during the annealing with reduced O2 partial pressure condition, it was proposed that an efficient SiC surface nitridation is achievable by following these steps: triggering the passive-to-active transition of the simultaneous surface oxidation by tuning the thermodynamic conditions and SiO2 thickness, and terminating the surface reaction at the beginning of the active-oxidation-dominant period by controlling the annealing time. It is confirmed that the observed interface passivation would be attributable to the N introduction to SiC/SiO2 interface, suggesting an opportunity to achieve an efficient interface N passivation following the proposed guideline.