Metalorganic Solution Deposition Research Articles

Photoconductivity and Photovoltaic Studies on Polycrystalline Bi1−xM′xFe1−yM″yO3−δ (M′ = K+ and Cs+; M″ = Ti4+; x = y = 0 and 0.1) Thin Films

The recent surge of interest in using all-inorganic materials like CsPbI3 for photovoltaic devices has brought significant interest in exploring the properties of BiFeO3 (BFO) by substituting Cs+ and K+ at the Bi3+ site. The aim of the present work is to study the parameters like controlling the lattice and surface oxygen vacancy (VO) defects which can significantly improve the photovoltaic device performances. Monovalent substituted and aliovalent co-substituted Bi1−xM'xFe1−yM"yO3−δ (M′ = K+ and Cs+; M" = Ti4+; x = y = 0 and 0.1) are grown on fluorine-doped tin oxide (FTO)/glass substrates by metal-organic chemical solution deposition method. Photoconductivity and photovoltaic properties of these films are studied in FTO/Bi1−xM'xFe1−yM"yO3−δ/Au capacitor configuration. Aliovalent substitution (for M' = K+ and Cs+, BK10FO and BCs10FO, respectively) at Bi3+ sites create VO in BFO thin films. Further, grain size reduction from 100 nm to 30 nm also results in the creation of surface VO defects. Tauc plot shows a reduction in the bandgap (Eg) values from 2.32 eV to 2.26 eV due to the formation of mid-bandgap VO defect states. Consequently, ferroelectric properties also get diminished. Aliovalent K+-Ti4+ co-substitution in BFO thin films brings back the Eg values to 2.3 eV, i.e., similar to pristine BFO thin films suggesting suppression of VO. This results in the revival of ferroelectric nature in aliovalent co-substituted thin films. Photoconductivity studies show two order enhancement in conductivity for BK10FO thin film devices compared to pure BFO. This enhancement is attributed to the mid-bandgap VO defect states due to aliovalent substitution. On the other hand, photoconductivity observed in BCs10FO devices is comparable with pristine BFO devices. Contrary to this, aliovalent co-substituted thin films show a decreasing trend of photoconductivity compared to M'+ substituted BFO suggesting that VO defects get suppressed due to charge compensation. Photoconductivity and photovoltaic device studies show similar behavior. BK10FO devices exhibit short circuit current density (JSC) ~0.45 µA/cm2, which is larger than that observed in BFO devices (JSC ~0.3 µA/cm2). But, BCs10FO devices show lesser JSC 0.07 µA/cm2. Open circuit voltage (VOC) observed in BFO devices is around 3 V which decreases to 0.1 V and 0.06 V for BK10FO and BCs10FO devices, respectively. This decrease in VOC is attributed to the reduction of the ferroelectric nature of the films. BFO, BK10FO, and BCs10FO devices show photovoltaic switching upon poling the films. Co-substituted thin films show a reduction in the JSC and betterment in the VOC compared to the monovalent substituted BFO thin films. This happens due to the suppression of VO defects by partial charge compensation in aliovalent co-substituted BFO films. This study explicitly brings out the role of VO on the photovoltaic and photoconductivity properties of BFO thin films.

Fabrication of YBCO Thin Films by Fluorine-Free MOCSD Method: Influence of Sintering Near the Melting Point

YBa 2 Cu 3 O 7-δ thin films were deposited by a fluorine-free metal-organic chemical solution deposition method using metal acetates as the starting materials. In this article, influence of different sintering temperatures (770-800 °C) on structural and superconducting properties of the films was investigated. Using a mixture of argon with 100 ppm oxygen as the atmosphere of the sintering process, some grain melting was observed at this temperature range, which favors to obtain a more c-axis epitaxial films with a higher critical current density. The decomposition mechanism of organic components of precursor powder was studied by Thermal Gravimetric Analysis (TGA)/Differential Scanning Calorimetry (DSC) analysis. The structural and morphological properties of the films were investigated by X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Atomic Force Microscopy (AFM) analysis. Four-point probe and inductive third-harmonic voltage measurements were carried out to determine transition temperature and critical current density, respectively. The film sintered at 790 °C showed a superconducting transition temperature at 91.5 K with a width of 1.2 K and a critical current density of 2 MA/cm 2 .

Influence of chemical solution growth and vacuum annealing on the properties of (100) pseudocubic oriented BiFeO3 thin films

BiFeO3 (BFO), a Pb-free perovskite oxide, is being explored for its potential use in a multitude of applications. We report on the oriented growth of BFO thin films using a facile metal-organic chemical solution deposition. Unlike the growth characteristics observed in Si/SiO2 and glass/FTO substrates, the solution growth process on sapphire (0001) is found to yield highly oriented thin films along (100)pc planes. Furthermore, annealing in air (BFO-A) and high-vacuum (BFO-V) ambients are done to explore the tunable limits of its physical properties. Temperature-dependent Raman studies highlight the high quality of thin films with sharp changes in Raman modes around transition temperatures. In addition, the films exhibit a hitherto unreported anomalous shift in A1(TO) and E(TO) modes around 450 K. The bandgap of BFO-V (Eg = 2 eV) is lower than that of BFO-A (Eg = 2.12 eV) and exhibits an increased defect photoluminescence emission. The magnetization (M) is twofold higher for BFO-V [M ≈ 42 (67) emu/cm3 at 300 K (5 K)]. In-plane and out-of-plane M vs H plots show larger anisotropy and hard hysteresis for BFO-A compared to BFO-V. Piezoelectric switching with d33 values of 5–10 pm/V is the characteristic of BFO ferroelectric materials. Photoconductivity measurements show a one order increase due to vacuum annealing. Carrier generation and recombination lifetimes are twofold faster in BFO-V as compared to BFO-A thin films. The controllable physical properties of oriented BiFeO3 thin films will be useful in magnetoelectrics and photoferroelectrics applications.

Advance in Long-Length REBCO Coated Conductors Prepared by Reel-to-Reel Metalorganic Solution and Ion-Beam-Assisted Deposition

In the present work, we report our recent efforts to improve the homogeneity of MgO buffer layers and superconducting YBa 2 Cu 3 O 7-δ coated tapes prepared by ion-beam-assisted deposition and metalorganic solution deposition (MOD), respectively. Based on previous research results involving fluorine, a reduced atmospheric pressure is used for the MOD technique to improve the in-plane texture and suppress microcracks in the film, and then more than 500 m of MOD-coated superconducting tape is manufactured, exhibiting an excellent biaxial texture and superconducting performance. The full width at half maximum values for both in-plane and out-of-plane textured films are as low as 3° based on X-ray diffraction (XRD) measurements. The superconducting current-carrying capacities for 12-mm tapes are approximately 450-520 and 450-500 A for the 100-m level and 500-m level (77 K, self-field), respectively. The current-carrying capacities were measured by both reel-to-reel transport and an inductive system, and the results demonstrated that the cost-effective MOD technique is very promising for long-length high-quality coated conductors.

Properties of Na<sub>0.5</sub>Bi<sub>0.5</sub>TiO<sub>3</sub>-SrTiO<sub>3 </sub>Ferroelectric Thin Films Prepared by a Modified MOSD Process

0.82NBT-0.18ST and 0.85NBT-0.15ST thin films have been prepared on Si substrates by a modified metalorganic solution deposition process. To achieve films with better ferroelectric properties, three main items have been changed in the process. Then the crystal structures, surface microstructures, hysteresis loops, fatigue curves and capacitance-voltage curves of the films were measured. It can be found that NBT-ST films can crystallize well after annealing at 650 °C for 5 minutes and have smooth surface microstructures. The 0.85NBT-0.15ST thin films exhibit better well-defined hysteresis loops than 0.82NBT-0.18ST, with a remnant polarization of 1.1 mC/cm2 and a coercive fields of 44.2 kV/cm. The clockwise C-V curves show that they have a desired polarization-type switching mode. The memory window of 0.82NBT-0.18ST thin film is about 1.8V, and that of 0.85NBT-0.15ST thin film is about 2.5V.

Artificial Multilayers of REBaCuO/YBaCuO and YBCO/CuO(Y2O3) for High-Performance Long Tapes of Coated Conductors Derived by Metal Organic Solution Deposition

Thick superconducting multilayer architectures consisting of alternate superconducting and superconducting layers DyBCO/YBCO and alternate superconducting and insulating layers YBCO/CuO(Y 2 O 3 ) are developed on buffered Hastelloy tapes using a metal organic deposition process. It is revealed that multilayer intermittent structures for superconducting layers are effective to avoid the presence of microcracks that occur with increasing thickness, which are frequently observed in monolayer films of REBa 2 Cu 3 O 7-δ (REBCO, RE = Y, Gd, or other rare earth elements). This paper shows that the thicknesses of DyBCO/YBCO multilayer films can reach 2.8 μm with a homogeneous, dense and crack-free surface morphology. The out-plane FWHM of the YBCO (005) peaks and the critical current value reach 1.1° and 365 A/cm (77 K, self-field) for such a thick film consisting of DyBCO/YBCO multilayers. It is also revealed that the introduction of a CuO layer is effective to avoid the presence of a-axis grains and voids of the YBCO films, which are frequently observed in multilayer films. Note that the introduction of CuO shows little negative influence on the texture of multilayer structure, especially for the bottom CuO. However, the in-plane texture deteriorates seriously for Y 2 O 3 /YBCO/YBCO multilayer film. The critical current density of YBCO films with middle CuO and bottom CuO are 2.0 MA/cm 2 and 2.5 MA/cm 2 (77 K, self-field), respectively. The microstructure optimization including the texture, uniformity, crack, defect, and porosity in the multilayered films is probably the reason for the enhancement of superconducting performance.

Switchable and Tunable BAW Duplexer Based on Ferroelectric Material.

A switchable and tunable bulk acoustic wave (BAW) duplexer for RF applications is presented in this paper. The fabricated BAW duplexer was built on sapphire substrate using solidly mounted resonators. A metal-organic solution deposition technique was used to form resonators with barium strontium titanate (BST) thin film and six layers of silicon dioxide and tantalum oxide as Bragg reflector. By applying dc bias, the BST thin film shows an electrostrictive effect, and the two filter paths of the BAW duplexer switch to a bandpass response with center frequencies at 4.635 and 4.878 GHz, showing a bandwidth of 119 and 154 MHz for the transmitting (Tx) and receiving (Rx) filters, respectively. Further, the BAW duplexer was simulated using the circuit, Butterworth-van-Dyke, and electromagnetic models. The simulated results are in agreement with the measurements and show the response of bandpass filters at center frequencies of 4.633 and 4.876 GHz for Tx and Rx, respectively.

Rapid fabrication of chemical-solution-deposited La0.6Sr0.4CoO3−δ thin films via flashlight sintering

This study demonstrates the sintering effectiveness of an intense pulsed light (IPL) sintering method for the fabrication of lanthanum strontium cobaltite (La0.6Sr0.4CoO3−δ, LSCO) thin films via xenon flashlight irradiation. LSCO thin film was coated on silicon (100) wafer via metal organic chemical solution deposition (MOCSD) methods and the flashlight irradiation process preceded instantly under ambient room temperature conditions. The properties of flashlight irradiated films were compared with thermally sintered ones as reference target. Electrical property, surface morphology, and crystallinity were observed to evaluate effectiveness of the flashlight sintering method by employing four-point probe apparatus, FE-SEM, and XRD, respectively. Considering that flashlight sintering process is procedurally accomplished in milliseconds under ambient room temperatures, this method may be able to circumvent several issues from the conventional thermal sintering process in realizing a convenient and available sintering process. The significance of this work lies in the demonstration of xenon flashlight sintering methods of perovskite oxides that are fabricated via wet chemical solution methods.

Metalorganic solution deposition of lead zirconate titanate films onto an additively manufactured Ni-based superalloy

Recent advances in additive manufacturing of high-temperature alloys for structural aerospace applications has led to interest in integrating additional functionality into such parts. Lead zirconate titanate (PZT) is a prototypical ferroelectric ceramic used as the electro-active material in many piezoelectric sensors and actuators. In this study, 300 nm thick PbZr0.2Ti0.8O3 (PZT 20/80) films were grown using metalorganic solution deposition onto additively manufactured substrates of Inconel 718. The microstructures of the films and the nature of the film/substrate interfaces were characterized using a combination of X-ray diffraction and electron microscopy techniques. Electrical measurements were performed to determine the ferroelectric, dielectric, and conductive responses of the PZT films. Our findings show that the PZT films exhibit robust ferroelectricity characterized by well-defined polarization-applied electric field (P-E) hysteresis loops. The samples display internal bias of up to ∼40 kV/cm. The room temperature remnant polarization and the small signal dielectric permittivity are ∼70 μC/cm2 and 205, respectively. The dielectric loss (tan δ) and the leakage current at 1 kHz are 9% and 1 nA at 1 V, respectively. We attribute the internal bias observed in the hysteresis loops and the overall large dielectric losses to the presence of an intermediate oxide layer at the PZT/Inconel interface, which forms during the high temperature crystallization of the ferroelectric film. These results show that it is possible to grow functional oxides with promising electrical properties onto additively manufactured metallic substrates.

Performance stability of strontium-doped lanthanum cobaltite ceramic cathode synthesized by a wet chemical method

Porous strontium-doped lanthanum cobaltite (La0.5Sr0.5CoO3−δ, LSC) thin film electrodes were deposited by a metal-organic chemical solution deposition method. These films were used as cathodic electrodes replacing precious metal electrodes for low-temperature solid oxide fuel cell (LT-SOFC) applications. They were characterized electrochemically and compared with devices that had platinum (Pt) cathodes. Pt was prepared by a DC magnetron sputtering method and LSC-YSZ-Pt and Pt-YSZ-Pt (cathode-electrolyte-anode) SOFC unit cells were fabricated. The performance of each cell was continuously evaluated under operating conditions and the performance of fuel cells with a Pt cathode was superior to those using a LSC cathode at the initial stages of operation; however, the output power density started to decrease as a function of time due to the degradation that comes from the heat vulnerability of Pt. As a consequence, the performance of Pt-YSZ-Pt was significantly lower than LSC-YSZ-Pt, and the electrode resistance grew to be about four times larger compared to before operation. In contrast, neither the output power density nor the electrode resistance of LSC-YSZ-Pt changed during operation. These results imply that LSC has better long-term performance stability compared to Pt and feasibility of using ceramic electrode for low-temperature solid oxide fuel cells.

Electrostatically driven dielectric anomaly in mesoscopic ferroelectric–paraelectric bilayers

We study the dielectric properties of 220 nm thick PbZr0.2Ti0.8O3/SrTiO3 (PZT/STO) ferroelectric (FE)–paraelectric (PE) bilayers with varying PZT/STO layer fractions grown onto Pt/Ti/TiO2/SiO2/Si substrates using metal–organic solution deposition. The films are characterized using a combination of X–ray diffraction and scanning transmission electron microscopy (STEM). A λ–type anomaly in the dielectric response is observed near a critical PZT/STO ratio of 0.25 STO. At this layer fraction, the small–signal dielectric permittivity exceeds 1600, which is significantly larger that the dielectric response of monolithic PZT and STO films deposited at the same conditions (∼600 and ∼200, respectively). In order to explain this behavior, a thermodynamic model is employed taking into account the electrostatic and electromechanical interactions between PZT and STO layers. We conclude that the observed dielectric anomaly is due to internal fields that result from the polarization mismatch between FE PZT and PE STO layers. Our results indicate that such internal fields can be used as a design parameter to produce structures with enhanced dielectric, piezoelectric, and pyroelectric properties as compared to those achievable for monolithic monolayer ferroelectric materials.

Synthesis and characterization of nanoporous strontium-doped lanthanum cobaltite thin film using metal organic chemical solution deposition

By employing strontium as a dopant of lanthanum cobaltite (LaCoO3), strontium-doped lanthanum cobaltite (La1−xSrxCoO3−δ, LSC) thin film was fabricated using a metal organic chemical solution deposition (MOCSD) method. Lanthanum nitrate hexahydrate [La(NO3)36H2O], strontium acetate [Sr(CH3COO)2], and cobalt acetate tetrahydrate [Co(CH3COO)24H2O] were used as precursors. The coating process was performed through a spin coating method on a substrate, which were then heat treated under various temperature conditions. Electrical properties, microstructures, and crystalline structures with respect to sintering temperature were analyzed. According to these analyses, the change in surface morphology, phase shift, and conductive properties were closely related, which could explain their respective behaviors. Furthermore, sintered strontium-doped lanthanum perovskite oxides showed various conductivities according to the amount of dopant. With the molar ratio of strontium that is stoichiometrically equivalent to lanthanum (La0.5Sr0.5CoO3−δ) thin film showed the best conductivity in the sintering temperature range of 650–700°C, with perovskite phases formed at this temperature condition. As the electrically conductive properties of the thin film are a function of thickness, the films were coated several times to a thickness of approximately 300nm, with the lowest resistivity (approximately 9.06×10−4Ωcm) observed at the optimized sintering temperature and solution composition.

Influence of Aliovalent Doping on Dielectric Properties of Ba0.6Sr0.4TiO3 Thin Film for Voltage Tunable Applications

Ba0.6Sr0.4TiO3 thin film with aliovalent doping of acceptor nature at ‘A’ lattice sites of ABO3 structure were prepared by a metal organic solution deposition (MOSD) technique on low loss quartz substrate. Oxide thin film having perovskite structure, namely, lanthanum nicklate (LaNiO3), also deposited using chemical solution deposition technique (CSD), was used as conductive bottom electrode. Solution properties and deposition process parameters were optimized for crack-free, uniform and smooth, pure and doped BST films on LNO electrode. The structural and microstructural analyses of the film were done using X-ray diffraction (XRD) and atomic force microscopy (AFM). Dielectric properties of the deposited film were studied using C-V and C-F electrical characterizations. The results indicate high tunability of 46%, very low loss tangent of 0.0065 with corresponding figure of merits of 71 for 2% K doped BST films at 1 MHz. The considerable improvement of dielectric properties of doped films compare to pure BST film is due to combined effect of perovskite lattice matched conductive bottom electrode and optimum doping level. These films had moderate dielectric constant, very low loss with good tunability which is suitable for tunable microwave applications.

Ag Doping Effects on Y0.5Gd0.5Ba2Cu3O7−δ multilayers derived by low-fluorine metalorganic solution deposition

Various artificial multilayers consisting of Y0.5Gd0.5Ba2Cu3O7−δ (YGdBCO) superconducting films were built up on an oxide buffered Hastelloy substrate using the low-fluorine metallorganic deposition method (MOD). Microscopic and superconducting performances are studied on composite YGdBCO multilayer films with and without alternate ultrathin layers of Ag, which comparatively demonstrates the Ag doping effects in such architectures. X-ray diffraction and scanning electron microscopy imply that the growth thermodynamic parameters of the YGdBCO are modified, resulting in a better c-axis orientation and a higher in-plane texture, as well as a superior surface, and finally give rise to great improvement of superconducting performance. To understand the above Ag doping effects further, the critical Gibbs free energy ΔG*(r) on nucleation of MOD-YGdBCO films on the biaxially textured buffer layers is analyzed with respect to the additions of Ag, which shows the competition between a-axis and c-axis growths subject to supersaturation. As a consequence, Ag additions may reduce the supersaturation at the growth interfaces, and hence give rise to a wider window of c-axis nucleation.

Fabrication of SrAl2O4:Eu2+ films on Si substrates via metal–organic solution

SrAl2O4:Eu2+ films were fabricated on the Si substrates by metal–organic solution deposition method and subsequent treatment up to 1100 °C. The phase and microstructure of the obtained films were characterized by DTA-TG, XRD, SEM and AFM. The composition of the film was confirmed by XPS. The luminescence properties of the films were measured by spectrophotometer. The effect of annealing temperature on the structure and luminescence was studied. It showed that the films had the pure monoclinic phase and the depth about 2 µm. Under the excitation of 254 nm, SrAl2O4:Eu2+ films exhibited an intense green emission band peaking at 528 nm, which originates from the 4f–5d transition of the Eu2+ ions. The quenching temperature of the emission is about 400 K. The results indicated that the SrAl2O4:Eu2+ films have good potential for use as a green phosphor for displays and/or white light emitting diodes.

Effect of Acetic Acid/Water Ratio on the Microstructure and Properties of LaNiO<sub>3</sub> Thin Films by Metal Organic Solution Deposition

Highly (100)-oriented LaNiO3(LNO) thin films were prepared onp-type Si (100) substrates by metal organic solution deposition (MOSD). The LNO thin films were driven by series precursor solutions with different ratio of acetic acid to deionized water (Raaw) and pH values. The dependences of viscosity, pH value and the thermal property of the gel-derived powders of the precursor solution onRaawvalues were systematically investigated. AFM images showed thatRaawcan dramatically influence the surface roughness. WhenRaawchanged from 7:1 to 1:1, the surface roughness decreased from 3.695 nm to 1.488 nm. The resistivities of all the films are less than 2.1×10-3Ω·cm. It shows that the precursor solution has strong effect on the microstructure of the thin films and relatively slight effect on the resistivity.

Phase Evolution of YBa2Cu3O7-x films by all-chemical solution deposition route for coated conductors

In order to understand the all-chemical-solution-deposition (CSD) processes for manufacturing coated conductors, we investigated the phase evolution of YBa2Cu3O7 (YBCO) films deposited by a low-fluorine metal-organic solution deposition (LF-MOD) method on CSD derived Ce0.9La0.1O2/Gd2Zr2O7/NiW. It is shown that the phase transition from the pyrolyzed film to fully converted YBCO film in the LF-MOD process is similar to that in typical trifluoroacetates-metal organic deposition (TFA-MOD) processes even though the amount of TFA in the solution is reduced by almost one half compared with typical TFA-MOD cases. Moreover, we found that the formation of impurities (mainly BaCeO3, NiWO4 and NiO) is strongly related to the annealing temperature, i.e., the diffusion controlled reactions become intensive from 760 oC, which might be connected with the poor structural and superconducting properties of the films deposited at high sintering temperatures. Based on these results, the optimized growth conditions of YBCO films were established, and a high critical current density (Jc) of about 2 MA/cm2 (77 K, self field) is achieved in a 200 nm thick YBCO film in the architecture made by our all CSD route.

Effect of Rb doping on ferroelectric and piezoelectric properties of Bi0.5Na0.5TiO3–BaTiO3 thin films

Rb doped 0.94Bi0.5Na0.5TiO3–0.06BaTiO3 (BNT–BT–Rbx) thin films with xmol% Rb (x=0, 2.5, 5, 7.5, 10) were deposited on Pt/Ti/SiO2/Si substrate by metal-organic solution deposition method. Experiments were conducted to investigate the effect of Rb doping on phase formation, microstructure, leakage current, and the resulting ferroelectric and piezoelectric property. It was found that substantial enhancement in structural, morphological and electrical properties can be achieved by Rb doping of BNT–BT thin films. Optimal electrical properties were obtained for 5mol% Rb doped BNT–BT thin films, with a dielectric constant, remnant polarization, and effective piezoelectric constant of ∼681, ∼28.9μC/cm2 and ∼86pm/V, respectively. It was suggested that the enhanced electrical properties in the case of 5mol% Rb BNT–BT thin films can be attributed to domain wall movement induced by A-site substitutions, large grain size, and lattice distortion.

Ferroelectric and piezoelectric properties of lead-free Bi0.5Na0.5TiO3–Bi0.5K0.5TiO3–BaTiO3-thin films near the morphotropic phase boundary

Abstract Lead-free Bi0.5Na0.5TiO3 (BNT)–Bi0.5K0.5TiO3 (BKT)–BaTiO3 (BT) piezoelectric thin films with compositions near the morphotropic phase boundary (MPB) were deposited by metal-organic solution deposition on Pt/Ti/SiO2/Si (1 0 0) substrates. The compositional dependences of their microstructure and ferroelectric/piezoelectric properties were investigated. The results indicated that all the thin films have a single-phase perovskite structure and show outstanding electrical properties at room temperature. We found that the thin film with a composition of 0.884BNT–0.08BKT–0.036BT showed the best structural and electrical properties, with a dielectric constant, remnant polarization, and effective piezoelectric constant of ∼638, ∼27 μC/cm2 and ∼79 pC/N, respectively. We suggest that these superior properties are due to this sample’s high degree of alignment of ferroelectric domains in the MPB region and largest grain size.

THE NEGATIVE EFFECT OF NON-NBT PHASE ON THE FERROELECTRIC PROPERTIES OF SR-DOPED NBT THIN FILM AND THE SOLUTIONS

Na0.5Bi0.5TiO3 (NBT) is a kind of excellent lead-free ferroelectric material. However, during the preparation of the NBT thin film by the chemical methods, the non-NBT phase is easier to be formed, which has a negative effect on the ferroelectric properties. In this paper, the Sr -doped NBT (SNBT) films were prepared by metal–organic solution deposition. The effects of Sr -doping amount, annealing temperature and duration on the appearance of non-NBT phase, and the relationship between the amount of non-NBT phase and the ferroelectric properties of the thin film was studied in detail. The results show that the appearance of the non-NBT phase in the SNBT is mainly because of the excessive amount of the doped ions or the excessive evaporation of Bi caused by long annealing duration. The excessive amount of the non-NBT phase will weaken the remanent polarization of the thin films. Using excessive 20% of Bi and reducing the annealing duration are the effective method for suppressing the non-NBT phase and improving the ferroelectricity of NBT-based film.