BaTiO3 Layer Research Articles

Heterogeneous Integration of High Endurance Ferroelectric and Piezoelectric Epitaxial BaTiO3 Devices on Si

AbstractIntegrating epitaxial BaTiO3 (BTO) with Si is essential for leveraging its ferroelectric, piezoelectric, and nonlinear optical properties in microelectronics. Recently, heterogeneous integration approaches that involve growth of BTO on ideal substrates followed by transfer to a desired substrate show promise of achieving excellent device‐quality films. However, beyond simple demonstrations of the existence of ferroelectricity, robust devices with high endurance are not yet demonstrated on Si using the latter approach. Here, using a novel two‐step approach to synthesize epitaxial BTO using pulsed laser deposition on water‐soluble Sr3Al2O6 (on SrTiO3 substrates), successful integration of high‐quality BTO capacitors on Si is demonstrated, with remanent polarisation Pr = 7 µC cm−2, coercive field Ec = 150 kV cm−1, ferroelectric and electromechanical endurance of > 106 cycles. The study further addresses the challenge of cracking and disintegration of thicker films by first transferring a large area (5 mm x 5 mm) of the templated layer of BTO (≈30 nm thick) on the desired substrate, followed by the growth of high‐quality BTO on this substrate, as revealed by high‐resolution X‐ray diffraction (HRXRD) and high‐resolution scanning transmission electron microscopy (HRSTEM) measurements. These templated Si substrates offer a versatile platform for integrating any epitaxial complex oxides with diverse functionalities onto any inorganic substrate.

Galerkin’s Method and Multivariate Newton’s Method for the Nonlinear Deformation of the Magneto-Electro-Elastic Bi-Layered Laminates

In this paper, mathematical modelling for the large deformation of a magneto-electro-elastic rectangular bi-layered laminate with general boundary conditions is presented. Constitutive equations involving the magneto-electro-elastic (MEE) material properties are introduced, Maxwell equations accounts for the electric and magnetic effects are also utilized. First-order shear deformation theory (FSDT) considering the von Karman nonlinear strain is adopted, and the plain strain/stress assumption applicable for thin plate analysis is used. A rather compact set of governing equations related to kinematical variables, electric/magnetic potentials and the Airy stress function is obtained as a consequence of the preliminary condensation for the electro-magnetic state to the plate kinematics. Semi-analytic solution for a bi-layered BaTiO3-CoFe2O4 laminate with specified boundary conditions subjected to various external applied loads is performed. By employing the Bubnov-Galerkin method, the set of nonlinear partial differential equations is transformed to a set of third-order nonlinear algebraic equations for the static deformation due to applied load. Numerical results are carried out by using the multivariate Newton's method with respect to various volume fractions indicating the volume ratio between piezoelectric BaTiO3 layer and piezomagnetic CoFe2O4. From the result, the nonlinearity of the von Karman strain appears to enhance system rigidity as smaller deformations will be detected when external load is applied. Also, some other interesting results are obtained which could be useful to future analysis and design of multiphase composite plates.

BaTiO3 boosted silver-based SPR sensor for efficient urine-glucose detection in pre-diabetic and early-diabetic stages

The current work studies the impact of BaTiO3 along with the various monosulfide on the sensing performance of a silver-coated surface plasmonic resonance sensor (SPR) for the noninvasive detection of glucose via urine samples. The considered monosulfides are GeS, ZnS, CdS, and CuS. After the optimization of the BaTiO3 thickness to 13 nm over the silver based SPR sensor, all above mentioned monosulfides are investigated over the BaTiO3 (BTO) layer individually. It is shown that GeS shows better performance compared to others. Maximum obtained sensitivity for the optimized structure (Prism (BK7)/ Ag (50 nm)/BaTiO3 (13 nm)/GeS (01 Layer)/Urine sample) is 527 °/RIU (the highest ever reported to date) for urine sample refractive indices range 1.335, 1.336, 1.337, 1.338, and 1.341 for corresponding glucose concentration of 0 g/dl (non-diabetic), 0.625 g/dl (pre-diabetic), 1.25 g/dl (early diabetic), 2.5 g/dl (diabetic), and 5 g/dl (high-diabetic), respectively. The investigation produced a thorough picture of the distribution of electric fields for distinct monosulfide layers. Other investigated sensing performance parameters such as detection accuracy (DA), quality factor (QF), limit of detection (LOD) are also numerically calculated and are 0.227 deg−1, 97 RIU−1 and 1.25e-5 respectively. The contrast of the suggested structure to similar relevant published work demonstrates its ability to be used as an efficient label-free biosensor.

Stable Zn metal anode enabled via ferroelectric nanotube arrays

Aqueous zinc-ion batteries are receiving increasing attention owing to their markedly high safety and low cost. However, the uncontrolled zinc dendrite growth and the side reactions at Zn-electrolyte interfaces hinder the practical application of aqueous rechargeable zinc-based batteries. Therefore, regulating the electrode/electrolyte interface to achieve dense zinc deposition is crucial for improving the electrochemical performance of zinc-ion batteries. Herein, ferroelectric composite nanotube arrays (BaTiO3 modified TiO2 nanotubes, TiO2@BaTiO3) are designed and fabricated as the three-dimensional current collector for Zn metal anode. Abundant zincophilic sites on the surface of BaTiO3 induce zinc nucleation, enabling a compact and horizontally-aligned Zn morphology. At external electric field, the depolarization field produced the ferroelectric BaTiO3 layer on the electrode surface can accelerate the dissociation of ZnSO4 and regulate the Zn-ion desolvation process at the interfaces, leading to dendrite-free Zn deposition and less byproducts. As a result, the TiO2@BaTiO3/Zn anode achieves reversible Zn plating/stripping with low overpotential for over 3000 h at 3 mA cm−2 in symmetric cells, and the assembled full battery exhibits a significantly enhanced cycling stability over 1800 cycles at 1 A g−1. Ferroelectric nanotube arrays brings new opportunities for next-generation aqueous zinc-ion batteries.

Strong Electrostatic Control of Excitonic Features in MoS2 by a Free‐Standing Ultrahigh‐κ Ferroelectric Perovskite

AbstractIntegrating free‐standing complex oxides with two‐dimensional (2D) materials has recently attracted great interest, due to the rich physics evolving from such structures. Enhancing and tuning the opto–electronic properties of these systems is of high importance for a multitude of applications, such as sensors, memory devices or optical communications. The electrostatic control of photoluminescence of monolayer MoS2 at room temperature via integration of free‐standing BaTiO3 (BTO), a ferroelectric perovskite oxide is presented. It is shown that the use of BTO leads to highly tunable exciton emission of MoS2 in a minimal range of gate voltages. Due to BTO's ferroelectric polarization‐induced doping, large peak emission shifts as well as a large and tunable A trion binding energy in the range of 40–100 meV are observed. These measurements are compared with those carried out when the BTO is replaced by a hexagonal boron nitride (hBN) dielectric layer, confirming BTO's superior gating properties and thus lower power consumption. Additionally, advantage of the ferroelectric switching of BTO is taken by fabricating devices where the BTO layer is decoupled from the gate electrode with a SiO2 layer. Choosing to isolate the BTO allows to induce large remanent behavior of MoS2’s excitonic features.

Optical Sensitive Detection of Cervical Cancer Based on Surface Plasmon Resonance Nanostructure

Cervical cancer is a disease that affects a lot of people all over the world. The success of treatment is significantly increased by early detection. The new surface plasmon resonance sensor (SPRS) described in this article is constructed from layers of silver, BaTiO3, and graphene, as well as a coupling prism. The transfer matrix (TM) approach is used to evaluate the SPRS structure. To obtain the highest sensitivity of the suggested SPRS, the thicknesses of the Ag and BaTiO3 and the number of Gr sheets are evaluated. Investigations are done on all factors of performance of the proposed device. Exemplary efficiency is achieved using 4 nm (BaTiO3) and 60 nm (Ag) materials. Three layers are chosen as the optimal amount of graphene after investigation. When the optimal thicknesses are employed, the suggested SPRS's greatest sensitivity of 300° RIU−1 has been attained. The suggested SPRS displays better sensitivity when compared to SPRS structures that have already been published in the literature. This SPRS is promising to be used in different biosensing applications due to its high performance.

Enhanced energy storage performance in Ag(Nb,Ta)O3 films via interface engineering

Dielectric capacitors with ultrahigh power density and ultra-fast charge/discharge rate are highly desired in pulse power fields. Environmental-friendly AgNbO3 family have been actively studied for its large polarization and antiferroelectric nature, which greatly boost the electric energy storage performance. However, high-quality AgNbO3-based films are difficult to fabricate, leading to a low breakdown field Eb (<1.2 MV/cm) and consequently arising inferior energy storage performance. In this work, we propose an interface engineering strategy to mitigate the breakdown field issue. A Ag(Nb,Ta)O3/BaTiO3 bilayer film is proposed, where the BaTiO3 layer acts as a p-type semiconductor while Ag(Nb,Ta)O3 layer is n-type, together with the n-type LaNiO3 buffer layer on the substrate, forming an n-p-n heterostructure. The n-p-n heterostructure elevates the potential barriers for charge transport, greatly reducing the leakage current. An extremely large breakdown field Eb∼4.3 MV/cm is achieved, being the highest value up to date in the niobate system. A high recoverable energy density Wrec∼62.3 J/cm3 and a decent efficiency η∼72.3% are obtained, much superior to that of the Ag(Nb,Ta)O3 monolayer film (Wrec∼46.4 J/cm3 and η∼80.3% at Eb∼3.3 MV/cm). Our results indicate that interface engineering is an effective method to boost energy storage performance of dielectric film capacitors.

Mixed volatility in a single device: memristive non-volatile and threshold switching in SmNiO3/BaTiO3 devices

Analog neuromorphic circuits use a range of volatile and non-volatile memristive effects to mimic the functionalities of neurons and synapses. Creating devices with combined effects is important for reducing the footprint and power consumption of neuromorphic circuits. This work presents an epitaxial SmNiO3/BaTiO3 electrical device that displays non-volatile memristive switching to either allow or block access to a volatile threshold switching regime. This behavior arises from coupling the BaTiO3 ferroelectric polarization to SmNiO3 metal–insulator transition; the polarization in the BaTiO3 layer that is in contact with the SmNiO3 layer modifies the device resistance continuously in a controllable, non-volatile manner. Additionally, the polarization state varies the threshold voltage at which the Joule-heating-driven insulator-to-metal phase transition occurs in the nickelate, which results in a negative differential resistance curve and produces a sharp, volatile threshold switch. Reliable current oscillations with stable frequencies, large amplitude, and a relatively low driving voltage are demonstrated when the device is placed in a Pearson–Anson-like circuit.

Direct Observation of Trace Elements in Barium Titanate of Multilayer Ceramic Capacitors Using Atom Probe Tomography.

Accurately controlling trace additives in dielectric barium titanate (BaTiO3) layers is important for optimizing the performance of multilayer ceramic capacitors (MLCCs). However, characterizing the spatial distribution and local concentration of the additives, which strongly influence the MLCC performance, poses a significant challenge. Atom probe tomography (APT) is an ideal technique for obtaining this information, but the extremely low electrical conductivity and piezoelectricity of BaTiO3 render its analysis with existing sample preparation approaches difficult. In this study, we developed a new APT sample preparation method involving W coating and heat treatment to investigate the trace additives in the BaTiO3 layer of MLCCs. This method enables determination of the local concentration and distribution of all trace elements in the BaTiO3 layer, including additives and undesired impurities. The developed method is expected to pave the way for the further optimization and advancement of MLCC technology.

Regulating ionic transport and interface chemistry via high-dielectric BaTiO3 porous scaffolds for aqueous Zn-ion batteries

Rechargeable aqueous Zn-ion batteries (AZIBs) are gaining considerable attention as alternatives to Li-ion batteries owing to their excellent safety, high energy density, low cost, and environmental friendliness. However, their Zn anodes suffer from severe dendritic growth, the hydrogen evolution reaction (HER), and corrosion, which limit the commercialization of AZIBs. To address this challenge, we designed a solution involving the development of a high-dielectric hydrophobic BaTiO3 (BTO) porous scaffold layer that is strategically applied to the Zn surface. This BTO layer effectively impedes the dendritic growth of Zn. The distinct polarizability of the BTO layer actively diminishes the electric-field gradient, thereby minimizing the interaction between the H2O molecules and the Zn surface. This phenomenon helps suppress dendritic growth, thus ensuring the uniform deposition of Zn and preventing the HER. The electrochemical performance of a symmetric cell containing the Zn@BTO electrode exhibits low-voltage polarization and stable charge–discharge performance for up to 500 h. In addition, a full-cell AZIB containing a high-capacity α-MnO2 cathode and Zn@BTO anode exhibits good rate capability and a long life of up to 500 cycles. This study demonstrates the development of a cost-effective dendrite-free Zn anode integrated with a highly dielectric hydrophobic BTO porous scaffold layer as a stable Zn–electrolyte interface layer for high-performance AZIBs.

Highly sensitive ZnO/Ag/BaTiO3/MoS2 hybrid structure-based surface plasmon biosensor for the detection of mycobacterium tuberculosis bacteria

This study presents a novel biosensor utilizing surface plasmon resonance (SPR) technology, comprising og zinc oxide (ZnO), silver (Ag), barium titanate (BaTiO3), and molybdenum disulfide (MoS2). The detection of mycobacterium tuberculosis bacteria was accomplished through the utilization of the hybrid structure. The transfer matrix method (TMM) and finite element method are employed to analyze the suggested surface plasmon resonance (SPR) structure. A comparative analysis has been conducted to evaluate the angular sensitivity between normal blood samples (NBS) and cells affected by tuberculosis (TB). The optimization of the performance of the surface plasmon resonance (SPR) structure involves adjusting the thickness of ZnO, Ag and BaTiO3 layer. The accurate measurement of the full width at half maximum (FWHM), detection accuracy (DA), quality factor and figure of merits (FOM) has also been conducted. The optimal angular sensitivity has been determined to be 10 nm for ZnO, 40 nm for Ag, 1.5 nm for BaTiO3, and one layer of MoS2 with a sensitivity of 525 deg./RIU. Additionally, this study compared the effects on sensitivity of two dimensional materials graphene, WS2 and MoS2. In contrast to the currently available biosensor utilizing surface plasmon resonance (SPR), the suggested structure exhibits higher angular sensitivity. Due to its improved sensitivity, the biosensor under consideration exhibits potential for detecting a wide range of biological analytes and organic compounds.

Direct imaging of the magnetoelectric coupling in multiferroic BaTiO3/La0.9Ba0.1MnO3

We report the direct imaging of the magnetic response of a 4.8 nm La0.9Ba0.1MnO3 film to the voltage applied across a 5 nm BaTiO3 film in a BaTiO3/La0.9Ba0.1MnO3 multiferroic heterostructure using x-ray photoemission electron microscopy (XPEEM). Specifically, we have written square ferroelectric domains on the BaTiO3 layer with an atomic force microscope in contact mode and imaged the corresponding magnetic contrast through the x-ray circular dichroic effect at the Mn L-edge with high spatial lateral resolution using XPEEM. We find a sudden decrease in the magnetic contrast for positive writing voltages above +6 V associated with the switching of the ferroelectric polarization of the BaTiO3, consistent with the presence of a magnetoelectric effect through changes in the hole carrier density at the BaTiO3/La0.9Ba0.1MnO3 interface. Temperature-dependent measurements show a decrease in the Curie temperature and magnetic moment in the areas where a positive voltage above +6 V was applied, corresponding to the hole depletion state and suggesting the onset of a spin-canted state of bulk La0.9Ba0.1MnO3. Our results are the first direct imaging of magnetoelectric coupling in such multiferroic heterostructure.

Boosting Efficiency of CIGS Solar Cell by Ferroelectric Depolarization Field

AbstractIncreasing the electric field in a solar cell is of importance to alleviate the carrier recombination and thus to increase the power conversion efficiency (PCE). In this paper, a strategy is reported to enhance the internal electric field of Cu(In,Ga)(Se,S)2 (CIGS) solar cells by inserting a ferroelectric BaTiO3 (BTO) layer into the device for the first time. The BTO location in the CIGS solar cell is found to play a vital role in the performances, which is due to the adjustment of the direction of BTO depolarization field. Impressively, the PCE is increased from 4.83% to 16.07% when the BTO depolarization field direction shifts from the opposite to the same direction to the p–n junction electric field. The improved PCE is due to the enhanced open‐circuit voltage (Voc), which suppresses carrier recombination and thus boosts the short‐circuit current density (Jsc) from 14.09 to 32.69 mA cm−2. These results unlock an effective strategy to improve the PCE of a CIGS solar cell by the application of a ferroelectric depolarization field. The facile deposition of BTO via sputtering method at room temperature enables its wide application in other solar cells to boost the PCEs.

Reduced leakage current and enhanced energy storage performance of BZNT/BTO multilayer structures: Implications in electronic devices

The extremely high recoverable energy density (Wrec) and efficiency (η) of lead-free thin films make them a promising candidate for application in miniature power devices. Here, a stable design of multilayered structures of BaTiO3 (BTO) and Bi[Zn2/3(Nb0.85Ta0.15)1/3]O3 (BZNT) have been fabricated using the pulsed laser deposition (PLD) technique on n-type Si, and Pt/Ti/SiO2/Si (Pt-Si) substrates. The effect of a number of stacking of alternate BTO and BZNT layers on the structural, microstructural, electrical, and ferroelectric properties is investigated. The films exhibited a polycrystalline nature, and the tetra-layer stacked film (BZNT/BTO3) exhibited better crystallinity, improvement in microstructure, and grain growth than that of the bi-layer stacked film (BZNT/BTO1). The improvement in ferroelectric response in the tetra-layer film is well correlated to the low leakage current density (∼10-7 A/cm2 at ±500 kV/cm) owing to reduced defects in the film. The reduced oxygen vacancies and dielectric loss tangent of order 10-3 validate the high quality of BZNT/BTO3 film exhibiting a large Wrec of 52.19 J/cm3 and high energy efficiency of 92.21 % achieved through interface engineering. These findings demonstrate the promising future for BTO-based multilayer thin film in high-power and energy-storage device applications.

Dual BaTiO3 layer-cavity assisted enhancement of copper-based surface plasmon resonance biosensor

Studies have shown that the two-dimensional transition metal dichalcogenides, graphene and MXene (Ti3C2Tx), and other materials not only can effectively improve the sensitivity of the surface plasmon resonance (SPR) biosensor but also reduce the detection accuracy. A SPR sensor based on dual barium titanate (BaTiO3) layers forming Fabry-Pérot (F-P) cavity was proposed to achieve this goal. Specifically, we employed a copper/nickel (Cu/Ni) bimetal as the plasmonic metal, two layers of BaTiO3 wrapped Cu/Ni bimetal to form a F-P cavity structure, and PMMA as the sensing layer. By optimizing the thickness of each film layer, the sensitivity reached 554.6 º/RIU, 6.2% higher than Cu/Ni/PMMA structure, and the corresponding full width at half maximum (FWHM) decreased by 15.4%. In addition, we used seven two-dimensional materials to replace PMMA but keeping other parameters unchanged, the obtained FWHM of the reflection spectrum was also reduced. These findings may benefit the application of the Fabry-Pérot cavity in biosensors and spectral modulation.

Enhanced photodetection through a perovskite BaTiO3 dielectric in a Si-MoS2 heterojunction.

The present investigation deals with the effect of a BaTiO3 (BTO) dielectric layer on the performance of MoS2/p-Si heterojunction photodetectors. The MoS2/p-Si junction demonstrates a responsivity of ∼80 A W-1 and detectivity of ∼1012 Jones. The inclusion of a dielectric BTO layer significantly enhances the performance of MoS2/p-Si photodetectors, leading to a remarkable improvement with a very high responsivity of ∼603 A W-1 and detectivity of ∼1013 Jones. The I-V characteristics of the MoS2/p-Si and MoS2/BTO/p-Si junctions under illumination can be understood by considering their respective energy band diagrams. This addition alters the energy band alignment, leading to higher conduction band offset and valence band offset values. The large photocurrent in forward bias in the MoS2/BTO/p-Si junction may be attributed to the presence of photogenerated electrons in the depletion region of BTO. BTO exhibits characteristics such as a long carrier diffusion length and low recombination rates, contributing to a reduction in carrier recombination within the photodetector for which the photocurrent of the MoS2/BTO/p-Si heterojunction can be improved significantly. The enhanced performance of the MoS2/BTO/p-Si junction, characterized by higher responsivity and detectivity, underscores the potential of this heterojunction for advanced photodetection applications, suggesting promising avenues for further research and development in the field of photodetectors. A comparative study with the available literature reveals that the excellent responsivity of ∼603 A W-1 and detectivity of ∼1013 Jones of the presently studied MoS2/BTO/p-Si heterojunction appear highly promising for various futuristic device applications.

Piezoelectric-enhanced n-TiO2/BaTiO3/p-TiO2 heterojunction for highly efficient photoelectrocatalysis

Charge separation is critical for achieving efficient solar-to-hydrogen conversion, whereas piezoelectric-enhanced photoelectrochemical (PEC) systems can effectively modulate band bending and charge migration. Herein, we design an n-TiO2/BaTiO3/p-TiO2 (TBTm) heterojunction in which the piezoelectric BaTiO3 layer is sandwiched between n-TiO2 and p-TiO2. The built-in electric field of TBTm can provide a strong driving force to accelerate carrier separation and prolong carrier lifetime. Consequently, the TBT3 achieves a prominent photocurrent density, as high as 2.13 mA cm−2 at 1.23 V versus reversible hydrogen electrode (RHE), which is 2.4- and 1.5-times higher than TiO2 and TiO2–BaTiO3 heterojunction, respectively. Driven by mechanical deformation, the induced dipole polarization can further regulate built-in electric fields, and the piezoelectric photocurrent density of TBT3-800 is 2.84 times higher than TiO2 at 1.23 V vs. RHE due to the construction of piezoelectric-heterostructures. This work provides a piezoelectric polarization strategy for modulating the built-in electric field of heterojunction for PEC system.

Surface Plasmon Resonance (SPR)−Triggered Polarization of BaTiO3 Surface on Ag Nanocubes Improves Photocatalysis

AbstractThe surface plasmon resonance (SPR)‐generated electric field (E‐field) intensities around a Ag nanocube (NC) before and after it is covered by a BaTiO3 (BTO) layer (BTO@Ag NC) were calculated. It was observed that the theoretical E‐field intensities were reduced on BTO@Ag NCs, thus suggesting inferior catalytic activities under visible light illumination. However, BTO@Ag NCs experimentally displayed better photocatalytic performance than that of Ag NCs under illumination at 633 nm, both in ambient argon (Ar) and in ambient air, where p‐aminothiophenol (PATP) molecules were used to probe the conversion. The mechanism can be attributed to the surface polarization of the BTO layer trigged by a SPR effect of the Ag core. The oscillation of free electrons in the Ag core aroused appearance of surface polarization charge on the ferroelectric (FE) BTO surface, which resulted in the enhanced catalytic properties of BTO@Ag NCs. Therefore, our finding may provide a novel method to enhance visible‐light responsive photocatalytic activity of wide bandgap FE materials by depositing them on plasmonic metal nanostructures.

A theoretical analysis of performance enhancement of SPR sensor based on ZnO and BaTiO3 for NH3 detection

Surface plasmon resonance (SPR) sensors have attracted enormous attention due to their applications in various fields. A novel SPR-based sensor with ZnO and BaTiO3 metal oxide layers is designed for NH3 gas detection. Gold and silver are used as plasmonic materials and corresponding results are compared. The prism and plasmonic materials effects on sensor response are investigated. Moreover, thicknesses of gold and silver and metal oxide layers are optimized to obtain suitable performance parameters. sensor response is analyzed in terms of minimum reflectance, sensitivity, detection accuracy and quality parameter. Applying ZnO and BaTiO3 layers lead to 37.88% and 26.03% enhancement of quality parameter and 37.91% and 26.07% improvement of detection accuracy, and more than 3.4 times improvement of detection resolution in gold and silver-based sensors, respectively. The recommended sensor structure provides appropriate performance parameters for 1 to 200 ppm of NH3 gas that can have potential applications in toxic gas sensing.

Twinning microstructure in the solid-phase epitaxial crystallization of BaTiO3

Amorphous BaTiO3 layers deposited on SrTiO3 (001) substrates at room temperature were subsequently crystallized using solid phase epitaxy (SPE). Heating an initially amorphous BaTiO3 layer in air at 650 °C for 3 h resulted in crystallization with components in two distinct crystallographic orientation relationships with respect to the substrate. Part of the volume of the BaTiO3 layer crystallized in a cube-on-cube relationship with the substrate. Other volumes crystallized in four variants of a 70.5° rotation about ⟨110⟩, resulting in a ⟨221⟩ surface normal in each case. Each of these four variants forms a Σ = 3 coincident site lattice with respect to the SrTiO3 substrate and the cube-on-cube oriented BaTiO3. Heating for the same duration and temperature in a reducing gas atmosphere resulted in the formation of polycrystalline BaTiO3 with no preferred crystallographic orientation. The dependence on the gas atmosphere indicates that it may be possible to tune the annealing time, temperature, and atmosphere to produce a single crystalline BTO on STO by SPE or produce a desired distribution of orientations.