Characteristics of ferroelectric Pb(Zr1-xTix)O3 thin film capacitors deposited on PtRhOy electrode barriers

We present the feasibility of single-layer PtRhOy thin films as electrode barriers for ferroelectric Pb(Zr(1-x)Tix)O-3 (PZT) (x = 0.2 to 0.8) thin film capacitors. PtRhOy thin films were deposited directly on n+ Si wafers by means of the reactive sputtering method. PtRhOy/PZT/PtRhOy/n+ Si capacitors showed well-saturated P-E hysteresis loops. The remanent polarizations, as well as the polarization loss after the switching repetitions, were varied with the ratio of Zr/Ti. Especially, Pb(Zr0.4Ti0.6)O-3 thin film capacitor showed the superior ferroelectric properties, such as the shape of P-E hysteresis loops and the behaviors of the polarization fatigue. The typical remanent polarization and the coercive field of this capacitor were 22 muC/cm(2) and 87 kV/cm, respectively, and the polarization loss was only less than 5 % after 10(11) switching repetitions. The chemical binding states of PtRhOy films affected mainly the shape of P-E hysteresis loops. From the measurement of the depth profile and the microstructure of this capacitor, it could be convinced that single-layer PtRhOx films behaved as high quality electrode barriers for PZT thin film capacitors.