Epitaxial Pb(Zr(sub x)Ti(sub 1(minus)x))O(sub 3)/SrRuO(sub 3) (x = 0, 0.35, 0.65) multilayer thin films on SrTiO(sub 3)(100) and MgO(100) prepared by MOCVD and RF sputtering

摘要

Epitaxial SrRuO(sub 3) thin films were deposited on SrTiO(sub 3)(100) and MgO(100) substrates by RF sputtering for use as bottom electrodes and epitaxial buffer layers. On these conductive substrates, epitaxial Pb(Zr(sub x)Ti(sub 1(minus)x))O(sub 3) (PZT; x = 0.35,0.65) and PbTiO(sub 3) (PT; x = 0) thin films were deposited by metalorganic chemical vapor deposition (MOCVD). X-ray diffraction (XRD), RBS channeling (RBS), transmission electron microscopy (TEM) and optical waveguiding were used to characterize the phase, microstructure, defect structure, refractive index, and film thickness of the deposited films. The PZT and PT films were epitaxial and c-axis oriented. 90(degree) domains, interfacial misfit dislocations and threading dislocations were the primary structural defects, and the films showed as high as a 70% RBS channeling reduction. Ferroelectric hysteresis and dielectric measurements of epitaxial PZT ferroelectric capacitor structures formed using evaporated Ag top electrode showed: a remanent polarization of 46.2 (mu)C/cm(sup 2), a coercive field of 54.9 kV/cm, a dielectric constant of 410, a bipolar resistivity of (approximately)5.8 (times) 10(sup 9) (Omega)-cm at a field of 275 kV/cm, and a breakdown strength of >400 kV/cm. Cyclic fatigue measurements showed that the remanent polarization was maintained for >10(sup 9) cycles.