Fatigue Properties of Epitaxial Pb(Zr_0.35Ti_0.65)O₃ Films with Various Volume Fractions of 90° Domains Grown on (100)_cSrRuO₃/(100)SrTiO₃ Substrates

(001)/(100)-oriented tetragonal epitaxial Pb(Zr_0.35,Ti_0.65)O₃ [PZT] thin films with various volume fractions of 90° domains were grown on (100)_cSrRuO₃∥(100)SrTiO₃ substrates by metalorganic chemical vapor deposition. The polarization-electric field hysteresis curve and fatigue behavior of a PZT capacitor with Pt and SrRuO₃ top electrodes were systematically investigated. In a Pt/PZT/SrRuO₃ capacitor, the degradation of switching polarization occurred between 10⁴ and 10⁷ cycles. In contrast, a PZT capacitor with SrRuO₃ top electrodes revealed almost fatigue-free behavior up to 10⁹ switching cycles. It was found that the fatigue properties of PZT films is strongly dependent on the type of top electrode, irrespective of the volume fraction of the (001) orientation. Moreover, it was also found that the a-domains switching of PZT thin films is independent of the fatigue properties.