Physical understanding of the reliability improvement of dual high-k CMOSFETs with the fifth element incorporation into HfSiON gate dielectrics

We clarified the impact of the fifth material incorporation into HfSiON technology for V th control on the reliability of high-k/metal gate stacks CMOSFETs. HfMgSiON is remarkably effective for suppressing electron traps, giving rise to a dramatic PBTI lifetime improvement for nMOSFETs. With pMOSFETs, Al incorporation is effective for the thermal deactivation of hole traps, resulting in NBTI lifetime improvement. We have established the guidelines of material selection to be incorporated into HfSiON for reliability improvement for nMOS and pMOS individually.