Defect Control for Large Remanent Polarization in Bismuth Titanate Ferroelectrics -- Doping Effect of Higher-Valent Cations --

Single crystals of K0.47Na0.53NbO3 (KNN) and Mn-substituted KNN (Mn-KNN, K0.53Na0.47Mn0.004Nb0.996Oy) were grown by a flux method, and the influence of lattice defects on the polarization and leakage current properties was investigated. As-grown KNN did not show an apparent polarization hysteresis loop due to its large leakage current (~10-3 A/cm2). The substitution of 0.4%-Mn at the Nb site and subsequent annealing under a moderate oxidative condition were effective in suppressing the leakage current of KNN crystals. 0.4%-Mn-KNN annealed at 1100°C in air exhibited a low leakage current (~10-8 A/cm2), a relatively large remanent polarization of 40 μC/cm2 and a coercive field of 12 kV/cm at 25°C. The oxidation of Mn and Nb ions during annealing in air is found to play an essential role in the low leakage current of Mn-KNN.

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Large remanent polarization and enhanced magnetic properties in non-quenched Bi(Fe,Ga)O3-(Ba,Ca)(Zr,Ti)O3 multiferroic ceramics

Applied Physics Letters ◽

10.1063/1.4978651 ◽

2017 ◽

Vol 110 (11) ◽

pp. 112902 ◽

Cited By ~ 10

Author(s):

Ningtao Liu ◽

Ruihong Liang ◽

Zhen Liu ◽

Zhiyong Zhou ◽

Chenhong Xu ◽

...

Keyword(s):

Magnetic Properties ◽

Remanent Polarization ◽

Large Remanent Polarization

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Large remanent polarization of 100% polar-axis-oriented epitaxial tetragonal Pb(Zr0.35Ti0.65)O3 thin films

Applied Physics Letters ◽

10.1063/1.1586993 ◽

2003 ◽

Vol 82 (26) ◽

pp. 4761-4763 ◽

Cited By ~ 56

Author(s):

Hitoshi Morioka ◽

Gouji Asano ◽

Takahiro Oikawa ◽

Hiroshi Funakubo ◽

Keisuke Saito

Keyword(s):

Thin Films ◽

Remanent Polarization ◽

Polar Axis ◽

Large Remanent Polarization

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Domain Dynamics of C-Axis Polarization in Bismuth Titanate Crystals

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.350.69 ◽

2007 ◽

Vol 350 ◽

pp. 69-72 ◽

Cited By ~ 1

Author(s):

Yuuki Kitanaka ◽

Yuji Noguchi ◽

Masaru Miyayama

Keyword(s):

Electric Field ◽

Remanent Polarization ◽

Bismuth Titanate ◽

Domain Walls ◽

Polarization Switching ◽

Optical Microscope ◽

Saturated Polarization ◽

Domain State ◽

Initial Nucleus ◽

Domain Dynamics

Polarization switching and domain dynamics in unpoled and poled crystals of bismuth titanate by applying electric field along the crystallographic c axis were investigated through polarization measurements and domain observations by optical microscope and piezoelectric force microscope. Poled crystals showed a well-saturated polarization hysteresis with a remanent polarization of 4.4 μC/cm2 and a coercive field of 4.7 kV/cm. Domain observations reveal that lenticular domain acts as an initial nucleus during polarization switching. The sidewise motion of the lenticular-domain walls and resultant single domain state were easily established for the poled crystals, while the lenticular domains observed in unpoled crystals were clamped even though a high electric field was applied to them.

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Ferroelectric Properties and Microstructures of Tb4O7-Doped Bi4Ti3O12 Thin Films

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.105-106.259 ◽

2010 ◽

Vol 105-106 ◽

pp. 259-262 ◽

Cited By ~ 1

Author(s):

X.A. Mei ◽

Min Chen ◽

A.H. Cai ◽

K.L. Su ◽

Chong Qing Huang ◽

...

Keyword(s):

Thin Films ◽

Magnetron Sputtering ◽

Layered Structure ◽

Remanent Polarization ◽

Single Phase ◽

Bismuth Titanate ◽

Ferroelectric Properties ◽

Rf Magnetron Sputtering ◽

Si Substrates ◽

Remarkable Improvement

Tb4O7-doped bismuth titanate (BixTbyTi3O12 BTT) thin films were fabricated on Pt/Ti/SiO2/Si substrates by rf magnetron sputtering technique, and the microstructures and ferroelectric properties of the films were investigated. Microstructure studies indicate that all of BTT films with well-developed rod-like grains consist of single phase of a bismuth-layered structure without preferred orientation. The experimental results indicate that Tb doping into Bi4Ti3O12 results in a remarkable improvement in ferroelectric properties. The remanent polarization (Pr) and coercive field (Ec) of the BTT film with y=0.6 were 22 μC/cm2 and 85 kV/cm, respectively.

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Large remanent polarization and small leakage in sol–gel derived Bi(Zn1/2Zr1/2)O3–PbTiO3ferroelectric thin films

Dalton Transactions ◽

10.1039/c2dt31996a ◽

2013 ◽

Vol 42 (2) ◽

pp. 585-590 ◽

Cited By ~ 13

Author(s):

Linxing Zhang ◽

Jun Chen ◽

Hanqing Zhao ◽

Longlong Fan ◽

Yangchun Rong ◽

...

Keyword(s):

Thin Films ◽

Remanent Polarization ◽

Sol Gel ◽

Large Remanent Polarization

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Formation and characteristics of highly c-axis-oriented Bi3.25La0.75Ti3O12 thin films on SiO2/Si(100) and Pt/Ti/SiO2/Si(100) substrates

Journal of Materials Research ◽

10.1557/jmr.2001.0431 ◽

2001 ◽

Vol 16 (11) ◽

pp. 3124-3132 ◽

Cited By ~ 33

Author(s):

Uong Chon ◽

Hyun M. Jang ◽

Sun-Hwa Lee ◽

Gyu-Chul Yi

Keyword(s):

Remanent Polarization ◽

Pyrochlore Phase ◽

Random Access ◽

Layered Perovskite ◽

Oriented Growth ◽

Plane Orientation ◽

Amorphous Surface ◽

Ferroelectric Random Access Memories ◽

Large Remanent Polarization ◽

Template Material

Highly c-axis-oriented Bi3.25La0.75Ti3O12 (BLT) films with a homogeneous in-plane orientation were successfully grown on SiO2/Si(100) and Pt/Ti/SiO2/Si(100) substrates by a sol-coating route. The substitution of lanthanum ions for bismuth ions in the layered perovskite suppressed the formation of pyrochlore phase and enhanced the c-axis-oriented growth. The c-axis-oriented BLT film fabricated on a Pt/Ti/SiO2/Si(100) substrate showed fatigue-free characteristics with a large remanent polarization of 26–28 μC/cm2 and the coercive field of 50–75 kV/cm. These features significantly enhance the potential value of the BLT film for the applications to high-density ferroelectric random-access memories devices. In addition, the c-axis-oriented BLT film, with a homogeneous in-plane orientation on an amorphous surface, can be used as a suitable template material for applications to various electro-magneto-optic devices.

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Ferroelectric Properties of Bismuth Titanate Ceramics by Dy3+/V5+ Substitution

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.412.306 ◽

2011 ◽

Vol 412 ◽

pp. 306-309

Author(s):

Chong Qing Huang ◽

Min Chen ◽

X.A. Mei ◽

Y.H. Sun ◽

J. Liu

Keyword(s):

Coercive Field ◽

Remanent Polarization ◽

Bismuth Titanate ◽

Ferroelectric Properties ◽

Polycrystalline Structure ◽

Oriented Polycrystalline ◽

Titanate Ceramics

The ferroelectricity of Bi3.25Dy0.75Ti3O12(BDT), and Bi3.25Dy0.75Ti2.97V0.03O12(BDTV) ceramics prepared at 1100°C by a conventional ceramic technique was investigated. These ceramics possess random-oriented polycrystalline structure. The remanent polarization (Pr) and coercive field (Ec) of the BDT ceramics are 15 µC/cm2and 64kV/cm, respectively. Furthermore, V substitution improves the Prvalue of the BDT ceramics up to 23 μC/cm2, which is much larger than that of the BDT ceramics. Therefore, co-sustitution of D and V in Bi4Ti3O12(BIT) ceramic is effective for the improvement of its ferroelectricity.

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