Negative bias-temperature instabilities in metal-oxide-silicon devices with SiO ₂ and SiO _xN _y/HfO ₂ gate dielectrics

The negative bias-temperature instability (NBTI) was compared in metal-oxide-silicon devices with SiO 2 and SiO xN y/HfO 2 gate dielectrics. Similar activation energies for oxide-trap and interface-trap charge formation was found due to NBTI in MOS capacitors with SiO 2 and SiO xN y/HfO 2 gate dielectrics. The results were consistent with the key roles played by hydrogen in MOS defect formation in MOS radiation response and long-term reliability. It was suggested that minimizing excess hydrogen, O vacancies, and/or oxide protrusions into Si may help to reduce NBTI.