Figure 1

$P\mathrm{\text{−}}E$ hysteresis loops and XRD patterns of bismuth titanate-based perovskites. (a) $P\mathrm{\text{−}}E$ hysteresis loops of $c$-axis oriented BT and BNdT film capacitors at an applied voltage of 10 V. (b) XRD patterns of BT and BNdT films on $\mathrm{P}\mathrm{t}/{\mathrm{T}\mathrm{i}\mathrm{O}}_2/{\mathrm{S}\mathrm{i}\mathrm{O}}_2/\mathrm{S}\mathrm{i}(100)$ substrates, showing a highly $c$-axis oriented preferential growth.Reuse & Permissions

Figure 2

(a) The refined unit-cell structure of BNdT ($x=0.85$) at 29 K. The Rietveld refinement was made using the DBWS program in the Cerius2 package. The degree of fitness in the refinement was quite satisfactory with $R_p=4.42\%$ and $R_{\mathrm{w}\mathrm{p}}=6.68\%$. The refinement indicated that, within the three perovskite layers, the oxygen octahedra were canted each other both on the $a\mathrm{\text{−}}b$ plane and along the $c$ axis with a zigzagging order, but the degree of canting into the $c$-axis direction of the octahedral layer decreased with increasing Nd modification. (b) The refined result of Ti1 and Ti2 sites projected on the $b\mathrm{\text{−}}c$ plane. Numerical values represent various real-space bond lengths between the central Ti ion and the surrounding oxygen ions. (c) The polarization vector of the Ti2 site projected on the $b\mathrm{\text{−}}c$ plane.Reuse & Permissions

Figure 3

Ti $K$-edge x-ray absorption spectra of the highly $c$-axis oriented BNdT film. The real-space SCF simulation [12] of XANES spectra presented in inset (a) was done using the FEFF8 module of the UWXAFS package [13]. The structural parameters refined by the Rietveld analysis were used as input parameters for the computation.Reuse & Permissions

Figure 4

Electrical fatigue characteristics of the $\mathrm{P}\mathrm{t}/\mathrm{B}\mathrm{N}\mathrm{d}\mathrm{T}/\mathrm{P}\mathrm{t}$ capacitor. (a) $P\mathrm{\text{−}}E$ hysteresis loops measured at an applied voltage of 5 V before and after $6.5\times {10}^{10}$ read/write switching cycles and (b) the fatigue-test results determined using a switching voltage of $\pm 3\mathrm{V}$ and a measuring voltage of 5 V at a frequency of 1 MHz.Reuse & Permissions

Figure 5

Charge-retentions and imprinting characteristics of the $\mathrm{P}\mathrm{t}/\mathrm{B}\mathrm{N}\mathrm{d}\mathrm{T}/\mathrm{P}\mathrm{t}$ capacitor at $85°\mathrm{C}$. Panel (a) represents four distinctive test-pulse sequences employed.Reuse & Permissions