Investigation of Coercive Field Shift During Cycling in HfZrOₓ Ferroelectric Capacitors

To fully understand the mechanisms for shifting of coercive field (
${E}_{\text {c}}$
) during the bipolar stress cycling in doped HfO
₂
ferroelectric (FE) material, we present a systematic study with both characterization and simulation on HfZrO
_x
(HZO) capacitor. First, with the help of time-dependent dielectric breakdown (TDDB) results, defect redistribution is found to be localized during the bipolar stress cycling. Then, with the advanced simulation framework Ginestra®, influences of work function (WF) mismatch of the electrodes and defect distribution on the
${E}_{\text {c}}$
symmetry and breakdown property are discussed. It indicates that the shift of
${E}_{\text {c}}$
is mostly due to the redistribution of defects from FE phase to non-FE phase and grain boundaries. Furthermore, nucleation limited switching (NLS) model is adopted to investigate the switching dynamics during coercive field shift in more detail.