Increase In Remanent Polarization Research Articles

Structural and physical properties of Pb(Zr0.4Ti0.6)O3 epitaxial film with LaNiO3 electrodes

Epitaxial LaNiO3 (LNO)/PbZr0.4Ti0.6O3 (PZT)/LaNiO3 heterostructures have been deposited on LaAlO3 (LAO) substrates, in which LNO films were prepared by magnetron sputtering and PZT films with thicknesses ranging from 40 nm to 160 nm were deposited via sol-gel method. It is found that the structural and physical properties of PZT films are closely related to the tetragonality (c/a-1). With increasing PZT thickness, both tetragonality and remanent polarization increase, and the maximum tetragonality and remanent polarization correspond to a 120-nm-thick PZT film capacitor with a remanent polarization of 61.6 μC/cm2 measured at 425.00 kV/cm. However, as the thickness of PZT film is further increased, the ferroelectric polarization decreases which is attributed to relaxation of the PZT film. The leakage current mechanism of the capacitor remains unchanged regardless of the PZT thickness. It is Space Charge Limited Current (SCLC) conduction mechanism at high electric fields and Ohmic conduction mechanism at low electric fields.

Energy storage properties influenced by relaxor ferroelectric properties dependent on the growth direction of epitaxial Bi2SiO5 thin films

Ferroelectric Bi2SiO5 (BSO) thin films were deposited by pulsed laser deposition on Nb-doped (100), (110) and (111) SrTiO3 (Nb:STO) substrates, resulting in (001)-, (113)- and (204)-oriented epitaxial films. Due to the crystallinity of BSO, in which the Bi2O2 layers are formed perpendicular to the c-axis direction, the (001)-oriented epitaxial BSO thin film showed the lowest remanent polarization and the best leakage current characteristics. On the other hand, the (113)- and (204)-oriented films showed an increase in remanent polarization due to the improvement of a-oriented crystallinity. Through experiments using vertical and lateral piezoresponse force microscopy, it has been confirmed that the distribution of in-plane-oriented domains reducing remanent polarization decreases in the order of (001)-, (113)- and (204)-oriented epitaxial BSO thin films. The epitaxial BSO thin films that exhibit ferroelectric hysteresis loops similar to the relaxor ferroelectric thin films tended to have improved energy storage characteristics as a result of improved remanent polarization and saturation polarization. In particular, the (113)-oriented epitaxial BSO thin film showed a high recoverable energy density of about 41.6 J cm−3 and an energy storage efficiency of about 85.6%.

Non-volatile memory characteristics of flexible ferroelectric field-effect transistors consisting of Sm-doped BiFeO3 thin films

This study investigates the impact of Sm doping on the structural, electrical, and functional properties of BiFeO3 (BFO) thin films. The aim is to improve their non-volatile memory characteristics for use in flexible ferroelectric field-effect transistors (FeFETs). We fabricated Sm-doped BFO (SBFO) thin films on flexible mica substrates with Sm concentrations ranging from 0 to 15 %. The FeFET device structures, which include MoS2 monolayer channels and SBFO thin films with Pt bottom electrodes, were analyzed. The SBFO thin films displayed a (111) preferential orientation due to the influence of underlying Pt electrodes. Notably, the SBFO thin film doped with a 10 % Sm concentration showed optimal enhancements, including a reduction in leakage current density and an increase in remanent polarization to 55.8 μC/cm2, compared to undoped thin film (35.5 μC/cm2). Furthermore, the thin film exhibited superior fatigue resistance for up to 1012 switching cycles and maintained stable values under significant bending stress for ferroelectric polarizations. On the other hand, SBFO thin film with 15 % Sm doping displayed relaxor antiferroelectric behavior, highlighting the importance of doping concentration. Therefore, for non-volatile memory application reliability, the FeFET device featuring a 10 % Sm-doped SBFO thin film not only enhanced the memory window but also showed superior fatigue characteristics over 1012 switching cycles, compared to its undoped counterpart. These findings demonstrate the effect of Sm doping in customizing the properties of BFO thin films for advanced, flexible non-volatile memory devices, offering a novel insight to optimize ferroelectric field-effect transistor performance.

Enhanced ferroelectric and magnetic properties of the 0–3 type BiFeO3-BaTiO3/BaFe12O19 composite multiferroic material

The 0–3 type (1-x)(0.75BiFeO3-0.25BaTiO3)/xBaFe12O19 (BFO-BTO/BaM) multiferroic composites were successfully prepared by a solid-state reaction sintering process. The coexistence of perovskite BFO-BTO phase and hexagonal BaM phase was confirmed for all BFO-BTO/BaM composites. Due to the large leakage current, the breakdown electric field decreased with increasing BaM content. Nevertheless, the ferroelectric properties of the composite ceramics have also been significantly improved, mainly as the increase of remanent polarization and the decrease of coercive field, where Pr = 19.79 μC/cm2, Ec = 30 kV/cm at x = 0.075. Meanwhile, the magnetic properties of BFO-BTO phase were enhanced, and the remanent magnetization linearly increased with increasing BaM content. The single domain magnetic structure was obtained for all BFO-BTO/BaM composite ceramics, and the magnetic properties changed after electric poling, which indicated the electric field controlled magnetic properties. The electric-controlled magnetic behavior was attributed to the structural phase transition. The magnetoelectric coupling coefficient αME of the composite material has been improved, with a maximum value of 0.61 mV/cm.Oe. Thus, the BFO-BTO/BaM magneto-electric composite system is a promising multiferroic system in information technology and sensing fields.

Wake-up-mitigated giant ferroelectricity in Hf0.5Zr0.5O2 thin films through oxygen-providing, surface-oxidized W electrode

The ferroelectricity of Hf0.5Zr0.5O2 thin films makes them good candidate materials for current and future electronic devices. To maximize the remanent polarization of Hf0.5Zr0.5O2, a new strategy is proposed to provide oxygen from a surface-oxidized W electrode. The ferroelectricity of Hf0.5Zr0.5O2 thin films with top and bottom TiN or W electrodes was compared to understand the effects of oxygen supply from the electrodes. Employing W top and bottom electrodes resulted in a double remanent polarization value of up to ∼60.25 μC/cm2; additionally, the wake-up effect was weaker than that observed when the TiN electrodes were used. The oxygen supply from the W electrode increased the grain radius by 161.34%, resulting in a 204.01% increase in remanent polarization. This suggests that the electrode material is a critical determinant of the ferroelectric properties of Hf0.5Zr0.5O2.

Tunability of magnetoelectric coupling in BiFeO3–PbZr0.52Ti0.48O3–CoFe2O4 tri-phase composites for ultra-fast switching applications

Magnetoelectric coupling an exquisite feature of multiferroics make them suitable for advanced technological applications like magnetic sensors, spintronic devices, and fast-switching devices, respectively. In the present work, a series of tri-phase composites (1-x)(0.7BiFeO3 +0.3PbZr0.52Ti0.48O3) + xCoFe2O4 (x = 0.00, 0.02, 0.04, 0.06, 0.08, 0.10) is synthesized through sol–gel auto-combustion method followed by the solid-state ball milling route. The analysis of X-ray diffraction patterns confirms the development of the rhombohedral perovskite phase of BiFeO3, the tetragonal phase of PbZr0.52Ti0.48O3, and the cubic spinel structure of CoFe2O4. The micrographs clearly show an increase in the average grain size by enhancing the CoFe2O4 contents having sharp and distinct grain boundaries. The energy-dispersive X-ray study assures the exact formation of a composite recipe through elemental mapping. The ferroelectric analysis comprising bipolar polarization versus electric field loops exhibits a significant decrease in maximum polarization with an increase in remanent polarization by enhancing the CoFe2O4 contents in the composite. The positive up and negative down sequence validates the presence of leakage current in all the samples with precise measurement of remanent polarization with and without switching polarization. The gradual increase of CoFe2O4 contents causes an increase in the magnetic response of the composites. Meanwhile, the magnetoelectric coupling phenomenon for all the composition shows a linear response whereas for x = 0.1 there is a slight reversibility observed, making this tri-phase composite a robust candidate for fast-switching devices.

Improved Ferroelectricity in Cryogenic Phase Transition of Hf0.5Zr0.5O2

Cryogenic transition from metastable tetragonal phase (t-phase) to orthorhombic phase (o-phase) is crucial in achieving the desired ferroelectric characteristics. Observing the reversible transition from anti-ferroelectricity (AFE) to ferroelectricity (FE) in electrical characteristics, the cryogenic phase transition is experimentally analyzed in Hf0.5Zr0.5O2 alloys. Furthermore, the stabilized o-phase formation is more favorable when applying cryogenics to superlattice Hf0.5Zr0.5O2, manifesting a 23% increase in remanent polarization (Pr) at 77K. To theoretically clarify the emergence of phase transition with decreasing temperatures, Landau-Ginzburg-Devonshire theory and firstprinciple study are combined in this work. Based on the detailed calculation, the increasing relative free energy of the t-phase contributes to lowering the energy barrier when decreasing the temperature, making the convenient transitional pathway from metastable t-to o-phase. This work exhibits the cryogenic phase transition model involving t-and o-phases in Hf0.5Zr0.5O2 and presents a method to boost ferroelectricity for emerging HfO2-based cryo-device.

Research on the Wake-up Effect of Ferroelectric HfO2-ZrO2 Thin Films

The appearance of ferroelectric (FE) and anti-ferroelectric (AFE) properties in HfO2-based thin films is highly intriguing in terms of both the scientific context and practical application in various electronic and energy-related devices. Interestingly, these materials showed a “wake-up effect”, which refers to the increase in remanent polarization with increasing electric field cycling number before the occurrence of the fatigue effect. The appearance of ferroelectric (FE) and anti-ferroelectric (AFE) properties in HfO2-based thin films is highly intriguing in terms of both the scientific context and practical application in various electronic and energy. In this paper, we have conducted an in-depth study on the relationship between the Wake-up effect in HfO2-based films and oxygen vacancies.

On the Origin of Wake‐Up and Antiferroelectric‐Like Behavior in Ferroelectric Hafnium Oxide

Ferroelectric hafnium oxide (HfO2) is considered a very prospective material for applications in integrated devices due to its considerably large spontaneous polarization and superior thickness scaling. In fact, the evolution of the ferroelectric hysteresis upon field cycling plays an important role in most applications; especially the so‐called wake‐up effect that describes the increase of remanent polarization for initial field cycling, needs a profound understanding in HfO2. Herein, the discovery of electric field–induced crystallization in hafnium oxide is reported. In addition, differences in the wake‐up behavior are addressed that finally can be categorized into five different cases, all being relevant when describing the evolution of ferroelectricity. Moreover, analysis of the temperature dependence and transmission Kikuchi diffraction provides insight into the underlying physical mechanisms of different wake‐up behavior scenarios, and proves ferroelastic switching as the origin for the observed antiferroelectric‐like behavior. This knowledge provides clear procedures of 1) how to experimentally quantify and 2) how to prepare and manufacture hafnium oxide phases for the five different wake‐up types.

Quenching‐circumvented ergodicity in relaxor Na1/2Bi1/2TiO3‐BaTiO3‐K0.5Na0.5NbO3

AbstractQuenching alkaline bismuth titanates from sintering temperatures results in increased lattice distortion and consequently higher depolarization temperature. This work investigates the influence of quenching on the ergodicity of relaxor Na1/2Bi1/2TiO3‐BaTiO3‐K0.5Na0.5NbO3. A distinct departure from ergodicity is evidenced from the increase in remanent polarization and the absence of frequency dispersion in the permittivity response of poled samples. Further, the samples exhibit enhanced negative strain upon application of electric field, indicating proclivity towards correlated polar nanoregions, corroborated by the enhanced tetragonal distortion. As a result, ergodic relaxor Na1/2Bi1/2TiO3‐6BaTiO3‐3K0.5Na0.5NbO3 exhibits a depolarization temperature of 85°C with a 60% increase in remanent polarization and approximately a threefold increase in remanent strain upon quenching. Quenching‐induced changes in the local environment of Na+ and Bi3+ cations hinder the development of ergodicity promoted by the A‐site disorder. These results provide new insight into tailoring ergodicity of relaxor ferroelectrics.

Effects of molar ratio on dielectric, ferroelectric and magnetic properties of Ni0.5Zn0.5Fe2O4-BaTiO3 composite ceramics

Ni0.5Zn0.5Fe2O4-BaTiO3 (NZFO-BTO) magnetoelectric composite ceramics with different molar ratios (mNZFO:mBTO = 1:1.5, 1.5:1 and 2:1, defined as N1B1.5, N1.5B1 and N2B1, respectively) were prepared successfully by using a joint hydrothermal method and sol-gel technique and sintering at 1000 ?C. Meanwhile, the dielectric, ferroelectric and magnetic properties of the composites were investigated. The presence of bi-phase structure in the composites was verified with X-ray diffraction analyses. The scanning electron microscopy images and energy dispersion spectrum results confirmed that the bulk-like grains (2 to 5 ?m) and spherelike grains (_0.5 ?m) could be attributed to NZFO and BTO, respectively. The dielectric constant and loss increased with increasing NZFO/BTO molar ratio because the carrier concentration of NZFO is higher than that of BTO. Thus, the dielectric constant of the N2B1 ceramics is more than 7800 at low frequency of 100Hz and room temperature, while only less than 2000 for the N1B1.5 composite. Two peaks can be observed in the temperature dependence of the dielectric constant curves. One is near 120 ?C, which corresponds to the Curie temperature of BTO, while the other peak occurs at about 320 ?C, corresponding to the relaxation polarization. The remanent polarization increases with increasing the content of ferroelectric BTO. The maximum value at 1 kHz was observed for the N1B1.5 sample and it is larger than 4.5 ?C/cm2, while the minimal value was obtained for the N2B1 composite and is only 1.2 ?C/cm2. Magnetic properties were also measured and it was observed that magnetization increases with increasing the molar ratio. The largest saturation magnetization has the N2B1 composite (_51.74 emu/g) due to the larger concentration of NZFO phase. However, the sample N1B1.5 shows the largest coercive field due to the highest interface interaction. This study provides guidelines for the fabrication of NZFO-BTO magnetoelectric composite ceramics.

Dielectric, pyroelectric and polarization behavior of polyvinylidene fluoride (PVDF) - Gold nanoparticles (AuNPs) nanocomposites

In this study, the polymorphism of poly (vinylidene fluoride) (PVDF) was control by gold nanoparticles (AuNPs). Simple one step method was used for synthesis of AuNPs using HAuCl4·3H2O, and N, N-dimethylformamide (DMF). The AuNPs of size 20–30 nm have been prepared by chemical method. DMF was act as reducing agent and solvent of PVDF. The circular samples of diameter 3.5 cm and thickness 10–25 μm were prepared. It has been observed that AuNPs modify the structural morphology of PVDF. The β-phase of PVDF was modified due to interaction between electric charge at the surface of AuNPs and CF2 dipoles. This is further verified by increase of remanent polarization in P-E loop. XRD spectra address the crystallographic phase identification of PVDF in presence of AuNPS. The AuNPs in PVDF matrix significantly enhances 72.2% expansion of remanent polarization (Pr), 19.23% depletion of coercive field (Ec) and 70–100% expansion of shifting speed of the ferroelectric polarization. Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) of pristine and NPs mixed PVDF illustrates the structural properties and reason of enhanced ferroelectric properties.

Stabilization of ferroelectric phase of Hf0.58Zr0.42O2 on NbN at 4 K

Ferroelectricity in doped and alloyed hafnia thin films has been demonstrated using several different electrodes, with TiN and TaN being most prominent. In this work, we demonstrate ferroelectric Hf0.58Zr0.42O2 thin films with superconducting NbN electrodes at cryogenic temperatures. Demonstration of polarization—electric field [P(E)] response at liquid helium cryogenic temperatures, 4 K, suggests that the polarization is switchable over a wide temperature range after an initial 600 °C anneal. Further, room temperature P(E) and capacitance measurements demonstrate an expected polarization response with wake-up required to reach the steady state. Wake-up cycling at 4 K is observed to have no effect upon the ferroelectric phase suggesting an oxygen vacancy mobility freeze out whereas wake-up cycling at 294 K demonstrates close to a 3× increase in remanent polarization. This integration of a ferroelectric Hf0.58Zr0.42O2 thin film with NbN demonstrates the suitability of a highly scalable ferroelectric in applications for cryogenic technologies.

Ferroelectric β-crystalline phase formation and property enhancement in polydopamine modified BaTiO3/poly (vinylidene fluoride-trifluoroethylene) nanocomposite films

Piezopolymer poly(vinylidene fluoride-trifluoroethylene) (PVDF-TrFE) films doped with BaTiO3 (BT) and polydopamine coated BT (BT-Pdop) nanoparticles were prepared by spin-coating method. Polydopamine modifies the interfaces of inorganic BT nanoparticles and PVDF-TrFE matrix with its polar hydroxyl groups, enhancing the piezoelectric β-phase. BT-Pdop nanoparticles were obtained in pH 8.5 buffer solution. For ferroelectric PVDF-TrFE, the favorable piezoelectric property comes from its ferroelectricity. Therefore, we studied the ferroelectric property of the nanocomposite films. The nanocomposite thin films possess better ferroelectric property than the pure PVDF-TrFE thin films, as demonstrated by the ferroelectric hysteresis curves. The remanent polarizations are 13.59 and 13.94 μC/cm2 after the doping of 1.0 wt% BT and 1.0 wt% BT-Pdop, respectively, which are about twice that of neat PVDF-TrFE. The piezoelectric β-ferroelectric phase increases with doping, according to X-Ray Diffraction analysis. In addition, the images of polarized optical microscopy and atomic force microscopy also reveal significant enhancement in crystallinity. The neat PVDF-TrFE is a semicrystalline polymer and the size of crystalline spherulites increases with the addition of BT and BT-Pdop nanoparticles. However, even the crystallinity of PVDF-TrFE considerably improved with polydopamine interfacial modification of BT, the increase of remanent polarization due to Pdop is only marginal. We infer that there are other defects at interfaces of BT-Pdop doped PVDF-TrFE nanocomposites which counteract the beneficial effect of the polar OH of polydopamine. Considerable enhancement on ferroelectric property of BT-Pdop doped PVDF-TrFE nanocomposites is expected after these issues are addressed.

Ferroelectric, dielectric properties and electrical conduction mechanism of epitaxial B1-xDyxFeO3 (x = 0.05, 0.075, 0.1, 0.125) thin films prepared by pulsed laser deposition

We report that Dy doping can be used to enhance ferroelectric properties and reduce leakage current in (001) epitaxial Bi1-xDyxFeO3 (BDxFO) thin films where x = 0.05, 0.075, 0.1, 0.125. The 120 nm thin BDxFO films were prepared by pulsed laser deposition (PLD). Saturated ferroelectric hysteresis (P-E) loops were observed at room temperature with an increase in remanent polarization (Pr) with the increase in applied electric field and Dy concentration. The improved Pr in BDxFO films from x = 0.05 to 0.1 is attributed to reduction in oxygen vacancies with an increase in Dy content that prevents electric domain back-switching. However, BDxFO (x = 0.125) film exhibit leaky and unsaturated loop which may be due to the appearance of microscopic defects in the film. The leakage current in BDxFO films decreased by an order of magnitude as Dy content increased from x = 0.05 to 0.1. The detailed leakage current mechanism analysis is also presented. The results of positive up negative down (PUND) method confirmed that intrinsic polarization is due to ferroelectricity and not due to leakage. Relative permittivity (ɛ') of BDxFO films increased whereas dielectric loss tangent (tan δ) reduced as Dy content increased from x = 0.05 to 0.1.

Polarization switching behavior of one-axis-oriented lead zirconate titanate films fabricated on metal oxide nanosheet layer

For the application of electronic devices using ferroelectric/piezoelectric components, one-axis-oriented tetragonal Pb(Zr0.40Ti0.60)O3 (PZT) films with thicknesses of up to 1 µm were fabricated with the aid of a Ca2Nb3O10 nanosheet (ns-CN) template for preferential crystal growth for evaluating their polarization switching behavior. The ns-CN template was supported on ubiquitous silicon (Si) wafer by a simple dip coating technique, followed by the repetitive chemical solution deposition (CSD) of PZT films. The PZT films were grown successfully with preferential crystal orientation of PZT(100) up to the thickness of 1020 nm. The (100)-oriented PZT film with ∼1 µm thickness exhibited unique polarization behavior of ferroelectric polarization, i.e., a marked increase in remanent polarization (Pr) up to approximately 40 µC/cm2 induced by domain switching under high electric field, whereas the film with a lower thickness showed only a lower Pr of approximately 11 µC/cm2 even under a high electric field. The ferroelectric property of the (100)-oriented PZT film after domain switching on ns-CN/Pt/Si can be comparable to those of (001)/(100)-oriented epitaxial PZT films.

Effect of ZnO Nanoparticles on the Sintering Behavior and Physical Properties of Bi0.5(Na0.8K0.2)0.5TiO3 Lead-Free Ceramics

Sintered Bi0.5(Na0.8K0.2)0.5TiO3 + x wt.% ZnO nanoparticle (BNKT–xZnOn) ceramics have been fabricated by conventional annealing with the aid of ultrasound waves for preliminary milling. Because of the presence of the liquid Bi2O3–ZnO phase at the eutectic point of 738°C, the sintering temperature decreased from 1150°C to 1000°C, and the morphology phase boundary of BNKT–xZnOn ceramics can be clarified by two separated peaks at (002)T and (200)T of 2θ in the x-ray diffraction (XRD) patterns. The improvement of ferroelectric properties has been obtained for BNZT–0.2 wt.% ZnOn ceramics by the increase of remanent polarization up to 20.4 μC/cm2 and a decrease of electric coercive field down to 14.2 kV/cm. The piezoelectric parameters of the ceramic included a piezoelectric charge constant of d 31 = 78 pC/N; electromechanical coupling factors k p = 0.31 and k t = 0.34, larger than the values of 42 pC/N, 0.12 and 0.13, respectively, were obtained for the BNKT ceramics.

Enhancement of dielectric and ferroelectric properties in cobalt ferrite doped poly(vinylidene fluoride) multiferroic composites

We report the effect of cobalt ferrite () nanoparticles on dielectric and ferroelectric properties of poly(vinylidene fluoride)(PVDF). Large enhancements in dielectric constant and remanent polarization upon addition of 5 wt.% nanoparticles to PVDF have been observed. Nearly 17% increase of dielectric constant and 31% increase in remanent polarization was observed in PVDF- nanocomposite films as compared to pristine PVDF films prepared under identical conditions. These enhancements were accompanied by a decrease in crystallinity and an increase in electroactive β-phase content as evidenced by x-ray diffraction and fourier transform infrared spectroscopy, respectively. A 5% increase in the amount of β-phase content is also observed in nanocomposite films. These enhancements in dielectric constant and remanent polarization are attributed to the influence of nanoparticles on nucleation, morphology, dipole aligning and dipole pinning behavior of PVDF.

Engineering of Ferroelectric HfO2-ZrO2 Nanolaminates.

In this work, the ferroelectric properties of nanolaminates made of HfO2 and ZrO2 were studied as a function of the deposition temperature and the individual HfO2/ZrO2 layer thickness before and after electrical field cycling. The ferroelectric response was found to depend on the structure of the nanolaminates before any postdeposition annealing treatment. After annealing with a TiN cap, an "antiferroelectric-like" response was obtained from nanolaminates deposited in an amorphous state at a lower temperature, whereas a ferroelectric response was obtained from nanolaminates deposited at a higher temperature, where crystallites were detected in thick films before annealing. As the individual layer thicknesses were decreased, an increased lattice distortion and a concurrent increase in remanent polarization were observed from the nanolaminates deposited at high temperatures. After field cycling, nanolaminates deposited at lower temperatures exhibited an antiferroelectric-like to ferroelectric transition, whereas those deposited at higher temperatures exhibited a larger remanent polarization. Finally, we demonstrate that by leveraging the proper choice of process conditions and layer thickness, remanent polarizations exceeding those of the HfZrO4 solid solution can be obtained.

Deposition barium titanate (BaTiO3) doped lanthanum with chemical solution deposition

Deposition of Barium Titanate (BaTiO3) thin films used Chemical Solution Deposition (CSD) method and prepared with spin coater. BaTiO3 is doped with lanthanum, 1%, 2%, and 3%. The thermal process use annealing temperature 900°C and holding time for 3 hours. The result of characterization with x-ray diffraction (XRD) equipment show that the addition of La3+ doped on Barium Titanate caused the change of angle diffraction.The result of refine with GSAS software shows that lanthanum have been included in the structure of BaTiO3. Increasing mol dopant La3+ cause lattice parameter and crystal volume become smaller. Characterization result using Scanning Electron Microscopy (SEM) equipment show that grain size (grain size) become smaller with increasing mole dopant (x) La3+. The result of characterization using Sawyer Tower methods show that all the samples (Barium Titanante and Barium Titanate doped lanthanum) are ferroelectric material. Increasing of mole dopant La3+ cause smaller coercive field and remanent polarization increases.