The effects of nitrogen and silicon profile on high-k MOSFET performance and Bias Temperature Instability

Nitrogen profile has been modulated by inserting Si layer into HfO_xN_y. In this paper, the effects of nitrogen and silicon on MOSFET performance and BTI (Bias Temperature Instability) characteristics have been investigated. Nitrogen incorporation enhanced V_TH shift for both PBTI (Positive Bias Temperature Instability) and NBTI (Negative Bias Temperature Instability). However, BTI degradation is significantly suppressed by the Si insertion. This improvement can be attributed to the reduction of oxide bulk trapped as well as interface trapped charge generation resulting from the insertion of Si layer.