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c-Axis oriented Tm3+-Dy3+-Eu3+ tri-codoped Bi2VO5.5 ferroelectric thin films were prepared on fused silica and Pt(111)/Ti/SiO2/Si substrates by using chemical solution deposition method, and charac...

Bi4-xPrxTi3O12 thin films were prepared by a chemical solution deposition method and their photoluminescence properties are investigated. The layered perovskite structure of the films is not destroyed by substituting Bi with Pr. The emission lines at 493, 533 and 612 nm are observed, and they can be assigned to the transitions of 3P0→3H4, 3P0→3H5 and 1D2→3H4 of Pr3+ ions. The quenching concentrations are identified to be x = 0.09 and 0.03 for the emissions at 493 and 612 nm. The crystal field plays a crucial role in the luminescence properties of Bi4-xPrxTi3O12 thin films.

Pb0.5Sr0.5TiO3 (PST50) thin films with different Cr doping amounts were prepared on LaNiO3 coated silicon substrates by a chemical solution deposition method. Their dielectric and ferroelectric properties were studied at room temperature. The dielectric constant decreased from 417 to 207 (at 1 kHz), as the Cr content increased from 0 to 8%. When the content of Cr was 3%, the tunability and the figure of merit factor reached maximal values of 61.3% and 21.4, respectively. The remnant polarization of the Cr-doped PST thin films decreased from 7.4 μC/cm2 to 2.0 μC/cm2, as the Cr content increased from 0 to 5%.

All-epitaxial multilayered ferroelectric thin films of (Bi,La)4Ti3O12(BLT)/ Pb(Zr,Ti)O3(PZT) were prepared on SrTiO3 substrates by pulsed laser deposition. X-ray pole-figure and electron diffraction analyses showed that the epitaxial relationships between BLT, PZT, and STO were BLT(001)//PZT (001)4//STO (001), and BLT[110]//PZT [100]//STO [100] for the multilayered thin films on (001)-oriented STO substrates, whereas for the multilayered thin films on (011)-oriented STO substrates, the epitaxial relationships between BLT, PZT, and STO were identified to be BLT(118)//PZT(011)//STO(011), and BLT[ 0]//PZT[100]//SrTiO3[100]. Clear interfaces between different film layers were confirmed by cross-sectional transmission electron microscopy observation. Tri-layered films of the same composition showed well-defined hysteresis loops as well as a high fatigue resistance up to 1 × 1010 switching cycles.

Growth of well(111)-oriented Pt and Pt/Ti films on SiO2/Si(111) substrates and crystallinity of PZT films grown on the Pt(111)/SiO2/Si(111) and Pt(111)/Ti/SiO2Si(111) substrates have been investigated. It was found by X-ray diffraction analysis that well (111)-oriented Pt film with a best full-width at half maximum (FWHM) of 0.28° was grown by the DC sputtering method. PZT films were prepared by metallo-organic decomposition (MOD) on Pt(111)-coated SiO2Si(111) substrates. The crystallinity of the PZT films improved as the FWHM of the Pt(111) diffraction peak decreased. The best FWHM obtained for a PZT film grown on a Pt(111)/Ti/SiO2/Si(111) substrate was 0.33°.

Piezoelectric ignition voltage and energy formula is derived from piezoelectric equations, the correlations of energy and piezoelectric material parameters are analysed by electromechanical coupling relation, and general conclusions about comprehensive selection of piezoelectric ignition material parameters are given, also

Expitaxial and highly oriented K(Ta0.65Nb0.35)O3 thin films were prepared on (100) SrTiO3 and (100) Mgo single crystal plates by sol-gel processing, using a multilayer sprinning method. The preparation process and the thin film characterization were studied by x-ray diffraction (XRD) and reflection high energy electron diffraction (RHEED). The mechanism of orientation of K(Ta0.65Nb0.35)O3 films was discussed in detail. The substrate strongly influenced on the film orientation, and the concentration of the precursor solution and heat-treatment conditions were also found to affect the orientation of the thin films.

Zinc oxide thin films were prepared from metallo-organic compounds through the sol-gel process. The crystal structure of ZnO films was investigated by XRD and SEM. Optical properties of the thin films were analyzed by using UV/visible spectroscopy. Strongly c-axis oriented ZnO thin films were obtained on fused quartz substrates; the surface of the thin films was smooth, homogeneous, crack-free, and dense. The growth of the thin films depends strongly on the heat-treatment conditions. The Crystal lattice constant of the thin films is a little larger than that of the ZnO crystal, the band gap is 3. 444 eV, and the absorption limit shifts to shorter wavelengths.