The influence of A-site rare-earth for barium substitution on the chemical structure and ferroelectric properties of BZT thin films

Journal Article · Thu Oct 15 04:00:00 EDT 2009 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2009.07.013· OSTI ID:21372324

Ostos, C ^[1]; Martinez-Sarrion, M L; Mestres, L ^[1]; Delgado, E ^[2]; Prieto, P ^[3]

---

1. Department of Inorganic Chemistry, University of Barcelona, C/Marti i Franques, 1-11, 08028 Barcelona (Spain)
2. Department of Physics, Universidad del Valle, Building 320-3001, Cali (Colombia)
3. Center of Excellence on Novel Materials, Universidad del Valle, A.A. 25360, Cali (Colombia)

Rare-earth (RE) doped Ba(Zr,Ti)O{sub 3} (BZT) thin films were prepared by rf-magnetron sputtering from a Ba{sub 0.90}Ln{sub 0.067}Zr{sub 0.09}Ti{sub 0.91}O{sub 3} (Ln=La, Nd) target. The films were deposited at a substrate temperature of 600 deg. C in a high oxygen pressure atmosphere. X-ray diffraction (XRD) patterns of RE-BZT films revealed a <001> epitaxial crystal growth on Nb-doped SrTiO{sub 3}, <001> and <011> growth on single-crystal Si, and a <111>-preferred orientation on Pt-coated Si substrates. Scanning electron microscopy (SEM) showed uniform growth of the films deposited, along with the presence of crystals of about half-micron size on the film's surface. Transmission electron microscopy (TEM) evidenced high crystalline films with thicknesses of about 100 nm for 30 min of sputtering. Electron-probe microanalysis (EPMA) corroborated the growth rate (3.0-3.5 nm/min) of films deposited on Pt-coated Si substrates. X-ray photoelectron spectroscopy (XPS), in depth profile mode, showed variations in photoelectron Ti 2p doublet positions at lower energies with spin-orbital distances characteristic of BaTiO{sub 3}-based compounds. The XPS analysis revealed that lanthanide ions positioned onto the A-site of the BZT-perovskite structure increasing the MO{sub 6}-octahedra distortion (M=Ti, Zr) and, thereby, modifying the Ti-O binding length. Polarization-electric field hysteresis loops on Ag/RE-doped BZT/Pt capacitor showed good ferroelectric behavior and higher remanent polarization values than corresponding non-doped system. - Graphical abstract: XPS narrow-scan spectra of Ti 2p doublets of the Nd-doped BZT films deposited on Pt-coated Si substrate.

• OSTI ID: 21372324
• Journal Information: Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Journal Issue: 10 Vol. 182; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALKALINE EARTH METAL COMPOUNDS
BARIUM COMPOUNDS
CHEMICAL ANALYSIS
COHERENT SCATTERING
CRYSTAL GROWTH METHODS
CRYSTALS
DIELECTRIC MATERIALS
DIFFRACTION
DOPED MATERIALS
ELECTRON MICROPROBE ANALYSIS
ELECTRON MICROSCOPY
ELECTRON SPECTROSCOPY
ELECTRON TUBES
ELECTRONIC EQUIPMENT
EPITAXY
EQUIPMENT
FERROELECTRIC MATERIALS
FILMS
GRAIN ORIENTATION
LANTHANUM COMPOUNDS
MAGNETRONS
MATERIALS
MICROANALYSIS
MICROSCOPY
MICROSTRUCTURE
MICROWAVE EQUIPMENT
MICROWAVE TUBES
MINERALS
MONOCRYSTALS
NEODYMIUM COMPOUNDS
NONDESTRUCTIVE ANALYSIS
ORIENTATION
OXIDE MINERALS
OXYGEN COMPOUNDS
PEROVSKITE
PEROVSKITES
PHOTOELECTRON SPECTROSCOPY
RARE EARTH COMPOUNDS
SCANNING ELECTRON MICROSCOPY
SCATTERING
SPECTROSCOPY
SPUTTERING
STRONTIUM COMPOUNDS
STRONTIUM TITANATES
THIN FILMS
TITANATES
TITANIUM COMPOUNDS
TRANSITION ELEMENT COMPOUNDS
TRANSMISSION ELECTRON MICROSCOPY
X-RAY DIFFRACTION
X-RAY PHOTOELECTRON SPECTROSCOPY
ZIRCONIUM COMPOUNDS