Composition Dependence of Dielectric Anomaly in Strontium Bismuth Tantalate Thin Films

AbstractEffects of off-stoichiometry and Nb substitution on the dielectric anomaly and ferroelectric properties have been investigated for SrBi2Ta2O9(SBT) thin films. Local atomic environment for the stoichiometric and off-stoichiometric SBT films has been also measured. The features of the dielectric anomaly, the Curie temperature (Tc), and the temperature dependence of the spontaneous polarization (Ps) are independent of the film thickness, and are governed by the nature of the crystal. For the stoichiometric Sr content SBT films, the grain size increases and the temperature dependence of the remanent polarization (Pr) decreases with increasing thickness. For the films with Sr/Bi/Ta = 0.8/2/2 and 0.8/2.2/2, Sr deficient local structure was observed, and such lattice structure probably leads to higher Tc than the stoichiometric crystal. Nb substitution for Ta also raises Tc, and makes the dielectric anomaly sharper. The phase transition associated with the dielectric anomaly for these films is thought to be first-order.

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Influence of Ta content on the physical properties of SrBi2Ta2O9 ferroelectric thin films

Journal of Materials Research ◽

10.1557/jmr.2006.0383 ◽

2006 ◽

Vol 21 (12) ◽

pp. 3124-3133 ◽

Cited By ~ 1

Author(s):

Fan-Yi Hsu ◽

Ching-Chich Leu ◽

Chao-Hsin Chien ◽

Chen-Ti Hu

Keyword(s):

Thin Films ◽

Physical Properties ◽

Spin Coating ◽

Coercive Field ◽

Remanent Polarization ◽

Ferroelectric Properties ◽

Ferroelectric Thin Films ◽

Preferential Orientation ◽

Strontium Bismuth Tantalate ◽

Metalorganic Decomposition

We have investigated the effect that the Ta content has on the ferroelectric properties of strontium bismuth tantalate (SBT) thin films synthesized using metalorganic decomposition (MOD) and spin coating techniques. The physical properties of these SBT samples were strongly dependent upon the Ta ratio. Polarization measurements revealed that Ta-deficient SBT exhibited a relatively low coercive field (2Ec ∼ 87 kV/cm) and a high remanent polarization (2Pr ∼ 15 μC/cm2). The value of 2Pr decreased as the Ta ratio in SBT increased. The improved ferroelectric properties of the Ta-deficient SBT samples may have resulted from the uniformly well-grown bismuth-layered-structured (BLS) phases of the films and their highly preferential orientation along the a and b axes. We suggest that the incorporation of Ta vacancies plays an important role in enhancing the crystallinities and microstructures of Ta-deficient SBT films.

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Improvement in Ferroelectric Properties of Sol-Gel Derived SrBi2Ta2O9 thin films with seeding layers

MRS Proceedings ◽

10.1557/proc-718-d10.11 ◽

2002 ◽

Vol 718 ◽

Author(s):

Ching-Chich Leu ◽

Chao-Hsin Chien ◽

Ming-Jui Yang ◽

Ming-Che Yang ◽

Tiao-Yuan Huang ◽

...

Keyword(s):

Thin Film ◽

Thin Films ◽

Magnetron Sputtering ◽

Remanent Polarization ◽

Ferroelectric Properties ◽

Sol Gel ◽

Strontium Bismuth Tantalate ◽

Seeding Layer ◽

Si Substrates ◽

Nucleation Sites

AbstractThe effects of a seeding layer, which was deposited on Pt/TiO2/SiO2/Si substrates using magnetron sputtering, on the characteristics of sol-gel-deposited strontium-bismuth-tantalate (SBT) thin films are investigated. The seeding layer serves as nucleation sites so homogeneous crystalline SBT films of bismuth-layered structure (BLS) with fine grains are successfully obtained by 750°C rapid thermal annealing in O2 ambient. The remanent polarization (2Pr) improves from 12.1 to 18.8 μC/cm2 with the addition of the seeding layer. In addition, the seeding layer also results in a lower nucleation temperature, allowing the use of 700°C annealing for 10 min to grow SBT films that are fully crystallized with BLS phase and shows good ferroelectric properties. Finally, crystallinity and microstructures of SBT films are found to be strongly dependent on the thickness of the seeding layer. Optimum Ta-seeded SBT thin film crystallized at 700°C for 10min depicts a higher 2Pr value (12.9 μC/cm2 (@5V) than that of the un-seeded films crystallized at 750°C for 1min.

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Synthesis and Ferroelectric Properties of Sol–Gel Derived Intergrowth-Superlattice-Structured SrBi4Ti4O15-Bi4Ti3O12 Thin Films

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.197-198.1781 ◽

2011 ◽

Vol 197-198 ◽

pp. 1781-1784

Author(s):

Hua Wang ◽

Jian Li ◽

Ji Wen Xu ◽

Ling Yang ◽

Shang Ju Zhou

Keyword(s):

Thin Films ◽

Remanent Polarization ◽

Annealing Temperature ◽

Ferroelectric Properties ◽

Sol Gel ◽

Hysteresis Loops ◽

Si Substrates ◽

Gel Processing ◽

Coercive Electric Field ◽

Clockwise Hysteresis

Intergrowth-superlattice-structured SrBi4Ti4O15–Bi4Ti3O12(SBT–BIT) films prepared on p-Si substrates by sol-gel processing. Synthesized SBT–BIT films exhibit good ferroelectric properties. As the annealing temperature increases from 600°C to 700°C, the remanent polarization Prof SBT–BIT films increases, while the coercive electric field Ecdecreases. SBT–BIT films annealed at 700°C have a Prvalue of 18.9µC/cm2which is higher than that of SBT (16.8µC/cm2) and BIT (14.6µC/cm2), and have the lowest Ecof 142 kV/cm which is almost the same as that of SBT and BIT. The C-V curves of Ag/SBT-BIT/p-Si heterostructures show the clockwise hysteresis loops which reveal the memory effect due to the polarization. The memory window in C-V curve of Ag/SBT-BIT/p-Si is larger than that of Ag/SBT/p-Si heterostructure or Ag/BIT/p-Si heterostructure.

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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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EFFECT OF GRAIN SIZE ON THE FERROELECTRIC PROPERTIES OF Bi3.25La0.75Ti3O12 Thin Films

International Journal of Modern Physics B ◽

10.1142/s0217979202015637 ◽

2002 ◽

Vol 16 (28n29) ◽

pp. 4469-4474 ◽

Cited By ~ 5

Author(s):

KYOUNG-TAE KIM ◽

CHANG-IL KIM ◽

DONG-HEE KANG ◽

IL-WUN SHIM

Keyword(s):

Thin Films ◽

Grain Size ◽

Remanent Polarization ◽

Ferroelectric Properties ◽

Fatigue Properties ◽

X Ray Diffraction ◽

X Ray ◽

Current Densities ◽

Metalorganic Decomposition ◽

Small Grains

The Bi 3.25 La 0.75 Ti 3 O 12 (BLT) thin films were prepared by metalorganic decomposition method. The effect of grain size on the ferroelectric properties during crystallization were investigated by x-ray diffraction and field emission scanning electron microscope. The grain size and the roughness of BLT films increase with increasing of drying temperature. The leakage current densities of the BLT thin film with large grains are higher than that with small grains. The remanent polarization of BLT increase with increasing grain size. As compared BLT with small grain size, the BLT film with larger grain size shows better fatigue properties. This may be explained that small grained films shows more degradation of switching charge than large grained films.

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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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Composition dependence of ferroelectric properties of epitaxial Pb(ZrxTi1−x)O3 thin films grown by metalorganic chemical vapor deposition

Journal of Crystal Growth ◽

10.1016/s0022-0248(01)01970-4 ◽

2002 ◽

Vol 237-239 ◽

pp. 455-458 ◽

Cited By ~ 15

Author(s):

Takahiro Oikawa ◽

Masanori Aratani ◽

Keisuke Saito ◽

Hiroshi Funakubo

Keyword(s):

Thin Films ◽

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Metalorganic Chemical Vapor Deposition ◽

Composition Dependence ◽

Ferroelectric Properties ◽

Chemical Vapor ◽

Metalorganic Chemical

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0.75SrBi2Ta2O9-0.25Bi3TiTaO9 Layered Structural Thin Films: Microstructure and Ferroelectric Properties

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.368-372.1814 ◽

2008 ◽

Vol 368-372 ◽

pp. 1814-1816

Author(s):

Dan Xie ◽

Zhi Gang Zhang ◽

Tian Ling Ren ◽

Li Tian Liu

Keyword(s):

Thin Films ◽

Surface Roughness ◽

Grain Size ◽

Coercive Field ◽

Remanent Polarization ◽

Ferroelectric Properties ◽

Significant Enhancement ◽

Solution Deposition ◽

Annealing Temperatures

{0.75SrBi2Ta2O9-0.25Bi3TiTaO9}(SBT-BTT) thin films were prepared by the modified metalorganic solution deposition (MOSD) technique. The microstructure and ferroelectric properties of SBTBTT thin films were studied. The SBT-BTT thin films were produced at 750°C. The grain size and surface roughness of SBT-BTT films showed significant enhancement with an increase in annealing temperatures. It is found that SBT-BTT thin films have good ferroelectric properties. The measured remanent polarization values for SBT-BTT, SBT and BTT capacitors were 15, 7.5 and 4.8μC/cm2, respectively. The coercive field for SBT-BTT capacitors was 50kV/cm. More importantly, the polarization of SBT-BTT capacitors only decreased 5% after 1011 switching cycles at a frequency of 1MHz.

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