Linear relationship between H+-trapping reaction energy and defect generation: Insight into nitrogen-enhanced negative bias temperature instability

Abstract

In this letter, we report a first-principles calculation which is well correlated to experiment on the role of nitrogen at Si/SiOxNy interface in negative bias temperature instability (NBTI). Our calculation shows that nitrogen’s lone pair electrons can trap dissociated hydrogen species more easily than oxygen. After trapping, a positive charge complex is formed and weakening of bond strength is observed at trapping site. Furthermore, as nitrogen concentration goes beyond 8 at. %, the neighboring effect from nitrogen starts to play a role in further degradation. The interfacial nitrogen dependence of the NBTI-induced defect generation is found to coincide with that of the H+-trapping reaction energy. Eventually, a linear correlation is found between the reaction energy and the defect generation. This provides an insight into nitrogen-enhanced NBTI.