First-principles calculations were reported which were closely related to experiments on the role played by N at Si/SiOxNy interfaces in negative-bias temperature instability. The calculations showed that the lone pair electrons of N could trap dissociated H species more easily than O. After trapping, a positive charge complex was formed, and weakening of bond strength was observed at trapping site. Furthermore, as N concentration went beyond 8at%, the neighboring effect from N began to play a role in further degradation. The interfacial N dependence of the negative-bias temperature instability-induced defect generation was found to coincide with that of the H+-trapping reaction energy. Eventually, a linear correlation was found between the reaction energy and defect generation. This provided an insight into N-enhanced negative-bias temperature instability.

Linear Relationship between H+-Trapping Reaction Energy and Defect Generation - Insight into Nitrogen-Enhanced Negative Bias Temperature Instability. S.S.Tan, T.P.Chen, J.M.Soon, K.P.Loh, C.H.Ang, W.Y.Teo, L.Chan: Applied Physics Letters, 2003, 83[3], 530-2