Accession Number : ADP006648

Title :   Device Effects of Various Zr/Ti Ratios of PZT Thin-Films Prepared by SOL-GEL Method,

Corporate Author : COLORADO UNIV AT COLORADO SPRINGS

Personal Author(s) : Watanabe, H. ; Mihara, T. ; Paz De Araujo, C. A.

Report Date : 05 APR 1991

Pagination or Media Count : 12

Abstract : PZT, PbZr sub x Tl sub 1-x 03, thin-films with various Zr/Ti ratios, 1 00/0 (lead zirconate) to 0/100 (lead titanate), were prepared by the sol-gel method. Basic electric properties, dielectric constant, tan sigma, P-E hysteresis curve, switching properties were measured respectively as a function of composition. Dielectric constant indicated a specific peak value (approximately 1100) around the morphotropic phase boundary between tetragonal and rhombohedral phase. Satisfactory low-voltage saturated hysteresis curves were observed for the compositions of PZT(90/10) through PZT(20/80). The remanent polarization and the coercive field increased as the titanium content decreased. The result of X-ray measurement showed that the lattice constants of thin-Film PZT are different from bulk ceramics for compatible compositions. The boundary, on which the c/a ratio must be 1 (rhombohedral phase), was slightly shifted to PbTiO3 side. This distortion in crystal structure is considered to be due to the thin-film effect, which the lattice mismatch between the platinum substrate and the PZT layer, restricted the ions to position into proper cites.

Descriptors :   *LEAD TITANATES, *ZIRCONATES, *FERROELECTRIC MATERIALS, BOUNDARIES, CONSTANTS, CRYSTAL STRUCTURE, CRYSTALS, DIELECTRICS, DISTORTION, FILMS, FUNCTIONS, GELS, HYSTERESIS, IONS, LAYERS, LOW VOLTAGE, MEASUREMENT, PEAK VALUES, PHASE, PLATINUM, POLARIZATION, RATIOS, STRUCTURES, SUBSTRATES, SWITCHING, THIN FILMS, VOLTAGE, X RAY SPECTROSCOPY, ELECTRIC SWITCHES.

Subject Categories : Ceramics, Refractories and Glass
      Mfg & Industrial Eng & Control of Product Sys

Distribution Statement : APPROVED FOR PUBLIC RELEASE