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The dielectric and conductive properties of Bi3.25La0.75TiO3 ferroelectric films were investigated in the temperature range of 25°C–600°C. A dielectric peak with a relaxation-type characteristic was observed around 400°C. This peak can be greatly suppressed or eliminated by high sintering temperature or annealing in an oxygen atmosphere (O2), and induced again by annealing in a reducing atmosphere (N2). The activation energy of dielectric relaxation and the characteristic relaxation time are estimated to be 1.89eV and 1.08×10−14s, respectively. In the corresponding temperature region, activation energy of conductivity is 0.65eV. The mechanism of this dielectric anomaly is discussed.

Epitaxially grown lanthanum-modified lead zirconate titanate (PLZT) thin films were deposited on r-cut sapphire substrates using an advanced sol-gel method. The methanol addition into sol-gel solutions brought high quality epitaxial growth of PLZT thin films. This film showed high electro-optic (EO) coefficients that were almost comparable to those of bulk PLZTs. We believe this PLZT deposition technique will open the door for the future data communication systems with integrated EO devices.

Ferroelectric Pb(Zr0.52Ti0.48)O3 (PZT) thin films with PbZrO3 (PZ) buffer layers were prepared on Pt(111)∕Ti∕SiO2∕Si(100) substrates using a hybrid rf magnetron sputtering and sol-gel process. Texture of PZT films was found to depend on Pb content of PZ buffer layers. Buffered PZT films displayed comparable ferroelectric properties (2Pr=38–53μC∕cm2,2Ec=136–170kV∕cm) with unbuffered PZT. Asymmetric leakage current and fatigue behavior with superior fatigue resistance was observed in PZ buffered PZT compared to unbuffered films. PZ buffer layers were found to affect crystallization and texture of PZT, and act as a capacitive interface layer possibly blocking charge injection from electrodes.

A new orientation control method for depositing (110)-oriented perovskite thin films was demonstrated using a (101)PdO//(111)Pd buffer layer on (100)Si substrates, which is widely used in integrated ferroelectric and dielectric applications. The (101)-oriented PdO was obtained by oxidizing (111)Pd films deposited on a (111)Pt/TiO x /SiO 2 /(100)Si substrate and (110)-oriented perovskites including SrRuO 3 and (Ba 0.5 ,Sr 0.5 )TiO 3 (BST) were obtained on (101)PdO by the RF magnetron sputtering method. Although the BST films deposited at 500 °C were not crystallized, the BST films deposited above 600 °C are fully crystallized and the (110)-orientation is dominant. The (110)-oriented BST thin film showed good dielectric property with high dielectric constant (>600) at 0 kV/cm and high tunability (>50% at +200 kV/cm). Comparing this dielectric property with those of other oriented BST films, both the dielectric constant and the tunability tend to decrease in the order of (111)-, (100)-, and (110)-preferred orientations.