Fatigue behavior of SrBi₂(Ta, Nb)₂O₉ ferroelectric thin films fabricated by pulsed laser deposition

The fatigue behavior for SBTN thin film capacitors with platinum electrodes (Pt/SBTN/Pt) on silicon wafers was investigated. Excellent electrical fatigue resistance was observed; the P_r during 10¹⁰ switching cycles did not display significant reduction. Optical fatigue becomes significant, however, with increasing illumination time to 50 s, the remanent polarization of the thin films shows about 78% reduction from its primary value. The optically induced polarization fatigue in SBTN films is due to trapping of photo-generated charge carriers at domain boundaries, resulting in polarization suppression. These results are helpful in understanding the fatigue-free response observed in electrical field, and are also necessary to fully characterize SBTN for memory applications.