Multiferroic and Nanomechanical Properties of Bi1−xGdxFeO3 Polycrystalline Films (x = 0.00–0.15)

In this work, we adopted pulsed laser deposition (PLD) with a Nd:YAG laser to develop Bi1−xGdxFeO3 (BGFO) films on glass substrates. The phase composition, microstructure, ferroelectric, magnetic, and nanomechanical properties of BGFO films are studied. BGFO films with x = 0.00–0.15 were confirmed to mainly consist of the perovskite phase. The structure is transformed from rhombohedral for x = 0.00 to pseudo-cubic for x = 0.05–0.10, and an additional phase, orthorhombic, is coexisted for x = 0.15. With increasing Gd content, the microstructure and surface morphology analysis shows a gradual decrease in crystallite size and surface roughness. The hardness of 5.9–8.3 GPa, measured by nanoindentor, is mainly dominated by crystallized structure and grain size. Good ferroelectric properties are found for BGFO films with x =0.00–0.15, where the largest remanent polarization (2Pr) of 133.5 µC/cm2 is achieved for x = 0.10, related to low leakage and high BGFO(110) texture. The improved magnetic properties with the significant enhancement of saturation magnetization from 4.9 emu/cm3 for x = 0 to 23.9 emu/cm3 for x = 0.15 by Gd substitution is found and related to large magnetic moment of Gd3+ and suppressed spiral spin structure of G-type antiferromagnetism. Furthermore, we also discuss the mechanisms of leakage behavior as well as nanomechanical characterizations as a function of the Gd content.

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Effect of Characteristics of SrRuO3 Buffer Layer on the Ferroelectric Properties of (Pb0.97La0.30)(Zr0.66Ti0.34)O3 Thin Films

MRS Proceedings ◽

10.1557/proc-541-313 ◽

1998 ◽

Vol 541 ◽

Cited By ~ 1

Author(s):

Yu-Jen Chen ◽

Gwo Jamn ◽

Kuo-Shung Liu ◽

I-Nan Lina

Keyword(s):

Thin Films ◽

Remanent Polarization ◽

Ferroelectric Properties ◽

Pulsed Laser ◽

Laser Deposition ◽

Low Leakage ◽

Low Leakage Current ◽

C 30 ◽

Plzt Thin Films ◽

Large Remanent Polarization

AbstractA two-step pulsed laser deposition (PLD) process, including PLD at a substrate temperature lower than 150°C and rapid-thermal-annealing (RTA) at around 550°C (30 s), has been successfully applied for growing (Pb0.97La0.03)(Zr0.66Ti0.034)0.9875O3, PLZT, thin films. Interdiffusion between layers is pronouncedly suppressed due to the presence of the SrRuO3 layer, which markedly improves the electrical properties of PLZT films. The PLZT films thus obtained exhibit large remanent polarization P,=19 µC/cm2 (with coercive force Ec=78 kV/cm), low leakage current density J11≤8 × 1O−6 A/cm2 (up to 400 kV/cm) and fatigue free characteristics.

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Effect of Diamagnetic A2+ Substitution on the Magnetic and Ferroelectric Properties of the Bi1−xAxFeO3 Multiferroics

MRS Proceedings ◽

10.1557/proc-1034-k10-76 ◽

2007 ◽

Vol 1034 ◽

Author(s):

V. A. Khomchenko ◽

D. A. Kiselev ◽

J. M. Vieira ◽

Li Jian ◽

A. M. L. Lopes ◽

...

Keyword(s):

Spin Structure ◽

Ionic Radius ◽

Ferroelectric Properties ◽

Piezoresponse Force Microscopy ◽

Weak Ferromagnetism ◽

Force Microscopy ◽

Microscopy Data ◽

A Site ◽

Induced Changes ◽

Spiral Spin

AbstractInvestigation of crystal structure, magnetic and local ferroelectric properties of the diamagnetically-doped Bi1−xAxFeO3 (A= Ca, Sr, Pb, Ba; x= 0.2, 0.3) ceramic samples has been carried out. It has been shown that the solid solutions have a rhombohedrally distorted perovskite structure described by the space group R3c. Piezoresponse force microscopy data have revealed the existence of the spontaneous ferroelectric polarization in the samples at room temperature. Magnetization measurements have shown that the magnetic state of these compounds is determined by the ionic radius of the substituting elements. A-site substitution with the biggest ionic radius ions has been found to suppress the spiral spin structure of BiFeO3 and to result in the appearance of weak ferromagnetism. The magnetic properties have been discussed in terms of doping- induced changes in the magnetic anisotropy.

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Ferroelectric Properties and Microstructures of Bi4-xDyxTi3O12 Thin Films

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.633.378 ◽

2014 ◽

Vol 633 ◽

pp. 378-381

Author(s):

Bei Li ◽

X.B. Liu ◽

M. Chen ◽

X.A. Mei

Keyword(s):

Thin Films ◽

Electrical Properties ◽

Layered Structure ◽

Remanent Polarization ◽

Single Phase ◽

Ferroelectric Properties ◽

Pulsed Laser ◽

Laser Deposition ◽

Deposition Technique ◽

Si Substrates

Dy-doped Bi4Ti3O12 thin films were fabricated on Pt/Ti/SiO2/Si substrates by pulsed laser deposition technique, and the structures and electrical properties of the films were investigated. XRD results indicated that all of Bi4-xDyxTi3O12 films consisted of single phase of a bismuth-layered structure with well-developed rod-like grains. The remanent polarization ( Pr ) and coercive field (Ec) of the Bi4-xDyxTi3O12 Film with x=0.75 were 25μC/cm2 and 85KV/cm , respectively.

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Effects of Zr/Ti Ratio on the Structure and Ferroelectric Properties in PZT-PZN-PMN Ceramics near the Morphotropic Phase Boundary

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.55-57.125 ◽

2008 ◽

Vol 55-57 ◽

pp. 125-128 ◽

Cited By ~ 1

Author(s):

R. Muanghlua ◽

S. Niemchareon ◽

Wanwilai C. Vittayakorn ◽

Naratip Vittayakorn

Keyword(s):

Transition Temperature ◽

Phase Boundary ◽

Coercive Field ◽

Phase Structure ◽

Remanent Polarization ◽

Perovskite Phase ◽

Ferroelectric Properties ◽

Piezoelectric Ceramics ◽

Pure Perovskite Phase ◽

All Ceramic

The piezoelectric ceramics of Pb(ZrxTi1−x)O3 – Pb(Zn1/3Nb2/3)O3 – Pb(Mn1/3Nb2/3)O3; PZT-PZN-PMN with Zr/Ti ratios of 48/52, 50/50 and 52/48 were fabricated in order to investigate the effect of compositional modifications on the ferroelectric properties of PZT-PZN-PMN ceramics. The phase structure of ceramics sintered at 1,150°C was analyzed. Results show that the pure perovskite phase was in all ceramic specimens, and the phase structure of PZT-PZN-PMN piezoelectric ceramics transformed from tetragonal to rhombohedral, with the Zr/Ti ratios increased in the system. The PZT-PZN-PMN ceramics with a Zr/Ti ratio of 50/50 exhibited the most promising properties including high remanent polarization and low coercive field of 25.95 µC cm−2 and 12.5 kV cm−1, respectively. Furthermore, the transition temperature decreased when the Zr/Ti ratio increased in the system.

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Perovskite phase formation and ferroelectric properties of the lead nickel niobate–lead zinc niobate–lead zirconate titanate ternary system

Journal of Materials Research ◽

10.1557/jmr.2003.0402 ◽

2003 ◽

Vol 18 (12) ◽

pp. 2882-2889 ◽

Cited By ~ 51

Author(s):

Naratip Vittayakorn ◽

Gobwute Rujijanagul ◽

Tawee Tunkasiri ◽

Xiaoli Tan ◽

David P. Cann

Keyword(s):

Ternary System ◽

Lead Zirconate Titanate ◽

Remanent Polarization ◽

Perovskite Phase ◽

Ferroelectric Properties ◽

Lead Zirconate ◽

Zirconate Titanate ◽

Lead Zinc Niobate ◽

Lead Zinc ◽

Lead Nickel

The ternary system of lead nickel niobate Pb(Ni1/3Nb2/3)O3 (PNN), lead zinc niobate Pb(Zn1/3Nb2/3)O3 (PZN), and lead zirconate titanate Pb(Zr1/2Ti1/2)O3 (PZT) was investigated to determine the influence of different solid state processing conditions on dielectric and ferroelectric properties. The ceramic materials were characterized using x-ray diffraction, dielectric measurements, and hysteresis measurements. To stabilize the perovskite phase, the columbite route was utilized with a double crucible technique and excess PbO. The phase-pure perovskite phase of PNN–PZN–PZT ceramics was obtained over a wide compositional range. It was observed that for the ternary system 0.5PNN–(0.5 - x)PZN–xPZT, the change in the transition temperature (Tm) is approximately linear with respect to the PZT content in the range x [H11505] 0 to 0.5. With an increase in x, Tm shifts up to high temperatures. Examination of the remanent polarization (Pr) revealed a significant increase with increasing x. In addition, the relative permittivity ([H9280]r) increased as a function of x. The highest permittivities ([H9280]r [H11505] 22,000) and the highest remanent polarization (Pr [H11505] 25 μC/cm2) were recorded for the binary composition 0.5Pb(Ni1/3Nb2/3)O3–0.5Pb(Zr1/2Ti1/2)O3.

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Structural, Dielectric and Pyroelectric properties of Lanthanum modified Lead Titanate Thin Films

MRS Proceedings ◽

10.1557/proc-811-d3.33 ◽

2004 ◽

Vol 811 ◽

Author(s):

Sonalee Chopra ◽

Seema Sharma ◽

T.C. Goel ◽

R.G. Mendiratta

Keyword(s):

Thin Films ◽

Lead Titanate ◽

Mechanical Stability ◽

Perovskite Phase ◽

Ferroelectric Properties ◽

Sol Gel ◽

Microstructural Analysis ◽

Pyroelectric Coefficient ◽

Structural Investigations ◽

Glass Substrates

ABSTRACTFerroelectric lead lanthanum titanate (Pb1−xLaxTi1−x/4O3) (PLTx) thin films (x=0.04,0.08 and 0.12) have been prepared by sol-gel spin coating process on ITO coated 7059 Corning glass substrates. Investigations have been made on the crystal structure, surface morphology, dielectric and ferroelectric properties of the thin films. For a better understanding of the crystallization mechanism, the structural investigations were carried out at various annealing temperatures (350°C, 450°C, 550°C and 650°C). Characterization of these films by X-ray diffraction shows that the films annealed at 650°C exhibit tetragonal structure with perovskite phase. Replacement of lanthanum in lead titanate results in reduction of tetragonal ratio (c/a), resulting in better mechanical stability. Microstructural analysis of the films are carried out by taking the Atomic Force Microscope (AFM) pictures. AFM images are characterized by slight surface roughness with a uniform crack free, densely packed structure. Dielectric, pyroelectric and ferroelectric studies carried out on these films have been reported. Dielectric constant and pyroelectric coefficient increase while Curie temperature decreases with increase in La content. The pyroelectric figures of merit of the films have also been calculated which suggest that 8% lanthanum is best suited material for pyroelectric detectors owing to its high pyroelectric coefficient (∼ 29nC/cm2 K), high voltage responsivity (∼420Vcm2/J), high detectivity (∼1.04×10−5Pa−1/2) and low variation of pyrocoefficient with temperature.

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Preparation and Electrical Properties of Bi0.9Nd0.1Fe0.925Mn0.075O3 Thin Films

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.557-559.1933 ◽

2012 ◽

Vol 557-559 ◽

pp. 1933-1936

Author(s):

Ning Yan ◽

Sheng Hong Yang ◽

Yue Li Zhang

Keyword(s):

Thin Films ◽

Remanent Polarization ◽

Ferroelectric Properties ◽

Sol Gel ◽

X Ray Diffraction ◽

Electrical Measurements ◽

X Ray ◽

Low Leakage ◽

Bifeo3 Thin Films ◽

Low Leakage Current

Pure BiFeO3(BFO) and Bi0.9Nd0.1Fe0.925Mn0.075O3(BNFM) thin films were deposited on Pt(111)/Ti/SiO2/Si substrate by sol-gel method. X-ray diffraction analysis showed that all the films were single perovskite structure and a phase transition appeared in Nd–Mn codoped BiFeO3 thin films. Electrical measurements indicated that the ferroelectric properties of BFO thin films were significantly improved by Nd and Mn codoping. BNFM films exhibit a low leakage current and a good P-E hysteresis loop. The remanent polarization (Pr) value of 74μC/cm2has been obtained in BNFM films, while the coercive field (Ec) is 184kV/cm.

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Structural and Electrical Properties of BiFeO3 Fabricated on C-Sapphire Substrates Using a Double SrTiO3/TiO2 Buffer Layer

Materials Science Forum ◽

10.4028/www.scientific.net/msf.687.385 ◽

2011 ◽

Vol 687 ◽

pp. 385-390

Author(s):

Xiu Wei Liao ◽

Jun Zhu ◽

Wen Bo Luo ◽

Lan Zhong Hao

Keyword(s):

Thin Films ◽

Buffer Layer ◽

Remanent Polarization ◽

Perovskite Phase ◽

Buffer Layers ◽

Electrical Performance ◽

Electrical Measurements ◽

Sapphire Substrates ◽

Low Leakage ◽

Low Leakage Current

BiFeO3 (BFO) thin films were deposited by pulsed laser deposition (PLD) on c-plane sapphire substrates with a double SrTiO3/TiO2 oxide buffer layer grown by laser molecular beam epitaxy (laser-MBE). X-ray diffraction data showed the highly (111)-oriented perovskite phase in the BFO films with SrTiO3/TiO2 buffer layers, compared to the polycrystalline thin film grown directly on sapphire substrates. The epitaxial BiFeO3 thin films inherit its orientation from the underlying SrTiO3 buffer layer and have two in-plane orientations: (111)[1-10] BiFeO3 // (0001)[1-100] Al2O3 plus a twin variant related by a 180° in-plane rotation. The BiFeO3 thin films with the buffer layer show an out-of-plane remanent polarization of 81.5μC/cm2, which is comparable to the remanent polarization of BiFeO3 prepared on other single crystal substrates. Electrical measurements demonstrate that the BiFeO3 thin films with the buffer layer exhibit excellent fatigue endurance and a low leakage current density relative to the films without the buffer layer. These results indicate that the (111)-oriented BiFeO3 films with favorable electrical performance could be epitaxially grown on sapphire substrates using the double SrTiO3/TiO2 buffer layer.

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Ferroelectric Characteristics of SrxBi2.4Ta2O9 Thin Films and Electrical Properties of the Pt/SrxBi2.4Ta2O9/TiO2/Si Structure

Materials Science Forum ◽

10.4028/www.scientific.net/msf.449-452.477 ◽

2004 ◽

Vol 449-452 ◽

pp. 477-480

Author(s):

J.H. Choi ◽

Tae Sung Oh

Keyword(s):

Thin Films ◽

Electrical Properties ◽

Coercive Field ◽

Remanent Polarization ◽

Ferroelectric Properties ◽

Memory Window ◽

Low Leakage ◽

Low Leakage Current ◽

Metalorganic Decomposition ◽

Ferroelectric Hysteresis

Ferroelectric characteristics of the 400 nm-thick SrxBi2.4Ta2O9(0.7≤x≤1.3) thin films processed by metalorganic decomposition were investigated, and electrical properties of the Pt/Sr0.85Bi2.4Ta2O9/TiO2/Si structure prepared using TiO2 buffer layer were characterized. The Sr-deficient SrxBi2.4Ta2O9 films exhibited well-developed ferroelectric hysteresis curves compared to those of the Sr-excess films. The Sr0.85Bi2.4Ta2O9 film exhibited optimum ferroelectric properties, such as high remanent polarization and low leakage current density, among SrxBi2.4Ta2O9 films. A memory window of the Pt/SrxBi2.4Ta2O9/TiO2/Si structure was dependent upon the coercive field of the SrxBi2.4Ta2O9 film, and the Pt/SrxBi2.4Ta2O9/TiO2/Si exhibited a maximum memory window of 1.3 V at the sweeping voltage of ±5 V.

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Robust ferroelectricity enhancement of PZT thin films by a homogeneous seed layer

10.21203/rs.3.rs-763002/v1 ◽

2021 ◽

Author(s):

jie jiang ◽

Lei Liu ◽

Kuo Ouyang ◽

Zhouyu Chen ◽

Shengtao Mo ◽

...

Keyword(s):

Thin Films ◽

Electrical Properties ◽

Remanent Polarization ◽

Perovskite Phase ◽

Ferroelectric Properties ◽

Sol Gel ◽

Pzt Thin Films ◽

Large Dielectric Constant ◽

Sol Gel Process ◽

A New Technique

Abstract With its excellent ferroelectric properties such as large dielectric constant and large remanent polarization, PZT thin films are extensively used in micro-sensors and other devices. In this study, the sol-gel process was used to fabricate Pb(Zr0.52Ti0.48)O3 thin films with Pb(ZrxTi1−x)O3 seed islands. The experimental consequences demonstrate that all the Pb(Zr0.52Ti0.48)O3 thin films with Pb(ZrxTi1−x)O3 seeds show pure perovskite phase with no other impurity phases, and the electrical properties of Pb(Zr0.52Ti0.48)O3 thin films modified by Pb(ZrxTi1−x)O3 seed islands with different Zr/Ti ratios are improved, such as remanent polarization increased, dielectric properties increased, coercive electric field decreased, leakage current density decreased, etc. In particular, the electrical properties of the Pb(Zr0.52Ti0.48)O3 thin films with Pb(ZrxTi1−x)O3 seed islands are the most optimal when the x is 0.52. This paper provides a new technique for optimizing the electrical properties of PZT thin films, which is of great significance for breaking through the bottleneck of the development of ferroelectric memory.

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