New Understanding on the Breakdown of High-K Dielectric Stacks using Multi-Vibrational Hydrogen Release Model

The breakdown of HfO₂, HfZrO₂ and HfSiON gate stacks with TiN metal gate under substrate injection regime is investigated and confronted with the multivibrational hydrogen release model. It turns out that for HfO₂ and HfZrO₂ because no Si-H bonds are present at the TiN interface, MVHR from Si-H bonds can not take place. Moreover, even adapting the model by supposing hydrogen release from another type of bond, or considering other conventional models, breakdown mechanism remains undefined. Nevertheless, for HfSiON for which Si-H bonds are present, modeling based on MVHR becomes consistent with experimental values.