Leakage Current Density Value Research Articles

Performance of normally off hydrogen-terminated diamond field-effect transistor with Al2O3/CeB6 gate materials

In this work, we demonstrate a hydrogen-terminated diamond (H-diamond) field-effect transistor (FET) with Al2O3/CeB6 gate materials. The CeB6 and Al2O3 films have been deposited by electron beam evaporation technique, sequentially. For the 4/8/12/15 μm gate length (LG) devices, the whole devices demonstrate distinct p-type normally off characteristics, and all the threshold voltage are negative; all the absolute values of leakage current density are 10−4 A/cm2 at a VGS of −11 V, exhibiting a relatively low leakage current density compared with CeB6 FETs, and this further demonstrates the feasibility of the introduction of Al2O3 to reduce the leakage current density; the maximum drain–source current density is −114.6, −96.0, −80.9, and −73.7 mA/mm, which may be benefited from the well-protected channel. For the 12 μm LG devices, the saturation carrier mobility is 593.6 cm2/V s, demonstrating a good channel transport characteristic. This work may provide a promising strategy for the application of normally off H-diamond FETs significantly.

Synthesis and characterization of (1-x)Bi0.9Sm0.1FeO3 - (x)BaZr0.15Ti0.85O3 based solid solution: Temperature-dependent dielectric and impedance properties

Lead-free solid solution of (1-x) Bi0.9Sm0.1FeO3 − (x) BaZr0.15Ti0.85O3 (BSFO − BZT) (x = 0.0, 0.10, 0.15, 0.20, 0.25, 0.50) ceramics were prepared using solid-state reaction method. The structural, morphological, temperature-dependent dielectric properties and leakage current were investigated. The structural investigation revealed the formation of perovskite structure coexisting with tetragonal and rhombohedral phases within (BSFO–BZT) ceramics. The dielectric measurements (within 303 K-773 K) confirmed the existence of a morphotropic phase boundary at x = 0.15 for the (BSFO–BZT) system. The frequency and temperature dependent electrical behavior were explained using Ac conductivity and impedance analysis. The leakage current behavior for all these samples was investigated using both space charge-limited conduction (SCLC) for bulk and Schottky emission (SE) for limited interface conduction approach, whereas the pure BSFO sample was found to be dominated by ohmic conduction, while the BZT-doped samples were dominated by grain boundary-limited conduction.The sample (0.80)Bi0.9Sm0.1FeO3-(0.15)BaZr0.15Ti0.85O3 achieved largest dielectric constant 330 at 10 KHz along with a moderate leakage current density value of 3.54 × 10-5A/cm2 (which is quite lower than pure BSFO) proven its candidacy to develop a stable photovoltaic, multilayer actuators, and ferroelectric memory devices.

Effect of ‘Mo’ doping into BiMnO3 on structural, dielectric, and leakage current properties

The simultaneous existence of more than one ferroicorder (ferroelectric, magnetic and ferroelastic) i.e., multiferroism in materials is the center of attention of the current materials researchers. Multiferroism is rare in the materials due to the different chemistry of the ferroic orders and highly useful in various device applications such as in spintronics. In this connection, BiMnO3 is one of the multiferroic materials among the number of available multiferroic materials. It shows ferroelectricity as well as antiferromagnetic nature simultaneously . In the present work, efforts have been made to synthesize the BiMnO3 in pure phase as well as with the doping of ‘Mo’ in the ratio of 2 %, 4 %, and 8 % via solid-state reaction route and denoted by BMM0, BMM2, BMM4, and BMM8, respectively. The structural analysis confirms the monoclinic structure along with some impurities and also confirms the polycrystalline nature of all the samples. Impurities reduce with the ‘Mo’ doping into BiMnO3. The dielectric and leakage current density measurements confirm the high dielectric constant, low dielectric loss, and low leakage current density values in the samples as increment in the ‘Mo’ content into the pure BiMnO3 phase. The BMM8 has the dielectric constant (∼2265 at 1 kHz and ∼ 385 at 10 kHz), dielectric loss (∼2.32 at 1 kHz and ∼ 2.66 at 10 kHz), and leakage current density (∼3.73 × 10-4 A/cm2 at 2 V and ∼ 1.00 × 10-3 A/cm2 at 3 V).

Normally-off Hydrogen-Terminated Diamond Field-Effect Transistor with SnOx Dielectric Layer Formed by Thermal Oxidation of Sn

SnOx films were deposited on a hydrogen-terminated diamond by thermal oxidation of Sn. The X-ray photoelectron spectroscopy result implies partial oxidation of Sn film on the diamond surface. The leakage current and capacitance–voltage properties of Al/SnOx/H-diamond metal-oxide-semiconductor diodes were investigated. The maximum leakage current density value at −8.0 V is 1.6 × 10−4 A/cm2, and the maximum capacitance value is measured to be 0.207 μF/cm2. According to the C–V results, trapped charge density and fixed charge density are determined to be 2.39 × 1012 and 4.5 × 1011 cm−2, respectively. Finally, an enhancement-mode H-diamond field effect transistor was obtained with a VTH of −0.5 V. Its IDMAX is −21.9 mA/mm when VGS is −5, VDS is −10 V. The effective mobility and transconductance are 92.5 cm2V−1 s−1 and 5.6 mS/mm, respectively. We suspect that the normally-off characteristic is caused by unoxidized Sn, whose outermost electron could deplete the hole in the channel.

Investigation of Leakage Current in Micro M-I-M Structure Using Multilayer High-K Dielectric Materials with COMSOL Multiphysics

Micro Metal-Insulator-Metal (M-I-M) capacitor structures are well-known passive components that have been broadly used in integrated circuits, Radio Frequency (RF) decoupling, Micro Electro Mechanical Systems (MEMS) sensors, and health monitoring systems. Thanks to its small dimensions, it can be easily integrated into microelectronics. With the acceleration of the scalling dawn of integrated circuits and systems, the size of the capacitor and other components must be reduced. It has become challenging to fabricate a micro M-I-M capacitor with low leakage current and high-capacity density since the leakage current and depletion effect are reported as the main factors of the gradual loss of electrical energy in the micro-M-I-M capacitor. Thus, minimizing the leakage current and the depletion effect became a new research trend. This paper presents a penta-layer high-K dielectric between the electrodes to reduce the leakage current in the micro-M-I-M capacitor. For this purpose, various dielectric materials were investigated. It was found that niobium pentaoxide (Nb2O5) and hafnium dioxide (HfO2) as penta-layer dielectric materials provide the lowest leakage current between the two electrodes. The recorded values of leakage current density are reduced to a mere 0.95 µAmps/mm2 from several µAmps/mm2 at the operating voltage of 1 V. The reported micro-M-I-M capacitor has potential application as an energy storage device.

Annealing temperature influenced physical properties of Al2TiO5 thin films for MIS devices

Aluminium titanate (Al2TiO5) thin films were deposited at room temperature by DC reactive magnetron sputtering. To make appropriate films for potential gate dielectric applications, we investigated the influence of annealing temperature on the structural, chemical and dielectric properties of Al2TiO5 thin films. From XPS studies, in as-deposited films, it has been observed that the presence of Al3+ and Ti4+oxidation states which correspond to Al2O3 and TiO2 respectively. After annealing at 400 °C in oxygen ambient, the binding energies of Al 2p, Ti 2p and O 1s were shifted by ~ 1 eV towards lower binding energy. This indicates the formation of an intermediate compound of Al2O3 and TiO2. The extracted Al, Ti and O ratio was 2:1:5 and it confirms the formation of Al2TiO5. XRD studies indicate that the as-deposited films were amorphous in nature. After annealing at 400 °C, diffraction peak at 2θ = 50.6° along (200) plane corresponds to aluminum titanate (Al2TiO5) has been observed. Metal-Insulator-Semiconductor (MIS) capacitors were fabricated and characterized to estimate the dielectric properties of the deposited films. The as-deposited films show low dielectric constant (κ = 8.1) and high leakage current density (J = 2.4x10-2 A/cm2 at -1V) values. After annealing at 400 °C the films show improved dielectric constant (κ = 9.4) and leakage current density (J = 4.6x10-9 A/cm2 at -1V) values. The enhancement in the device properties can be attributed to the improved oxide and interface quality after annealing. Equivalent oxide thickness (EOT) of less than 1nm is required to use Al2TiO5 as an alternate gate dielectric to SiO2 in CMOS industry. To achieve this scaling of the dielectric thickness (<5 nm) is needed, which is under investigation. Copyright © 2017 VBRI Press.

Optimization and integration of ultrathin e-beam grown HfO2 gate dielectrics in MoS2 transistors

Integration of high-k dielectrics with two-dimensional (2D) layered semiconductors is one of the bottleneck in realization of the devices in a viable technology. In this work we report on the optimization and integration of electron beam (e-beam) evaporated, ultrathin (5 nm) HfO2 thin films on a few layer (5–7 nm) MoS2 substrate, without the need for any functionalization and buffer layers. The effect of HfO2 film thickness on optical, compositional and electrical properties of the material has been evaluated using ellipsometry, Rutherford backscattering, x-ray photoelectron spectroscopy and electrical measurements. The estimated dielectric constant and leakage current density values have been correlated with the refractive index and density of the films. It has been observed that the dielectric constant decreased drastically in ultrathin (5 nm) HfO2 film in case of Al as a gate electrode due to the formation of interfacial layer. The effect of gate electrode material and its processing on dielectric properties of ultra-thin films has been studied in detail and it is found that e-beam evaporated Ni seems to be a promising gate electrode. Equivalent oxide thickness of 1.2 nm and leakage current density (J) of 1.1 × 10−4 A cm−2 have been achieved for 5 nm films with Ni as gate electrode. Top gated MoS2 transistors with, 5 nm HfO2 gate dielectric show very good performance with I ON to I OFF ratio of 106. We thus demonstrate e-beam evaporation as a promising technique to directly integrate high-k dielectrics (HfO2) with 2D materials.

Electrical and Microstructural Characterization of TiO2 Thin Films for Flexoelectric Devices

This work investigates the flexoelectric potential of titanium oxide thin films regarding their microstructural and electrical properties to be integrated into nanoscaled resonators. Flexoelectricity is an electromechanical effect that can result in deformation of a material due to a polarization gradient and can outperform piezoelectric effects at the nanoscale. The flexoelectric constant is linearly dependent on the permittivity and therefore we determined TiO2 as a suitable flexoelectric material because of its high permittivity, its CMOS compatability and its linearity with respect to polarization. TiO2 capacitors with various electrode materials are evaluated in order to achieve the c-axis oriented (110) rutile growth, thus to exploit the highest permittivity. The permittivity ranges from 65 to 95, with TiO2 on IrO2 electrodes representing the highest value achieved in this study. As expected, the IrO2/TiO2/IrO2 capacitors show an almost constant impedance up to 200 kHz and have leakage current density values of ∼10−3 A/cm2 at 0.5 MV/cm at room temperature.

Structural, Magnetic, and Electrical Properties of (1-x) Na0.5Bi0.5TiO3 –(x) NiFe2O4(x = 0.1, 0.3, 0.5, 0.7, and 0.9) Multiferroic Particulate Composite

Multiferroic composites consisting of Na0.5Bi0.5TiO3(NBT) and NiFe2O4(NFO) phases have been synthesized by using sol-gel and metal-organic decomposition (MOD) methods. The X-ray diffraction (XRD) and scanning electron microscopy (SEM) results confirm NBT and NFO phase formation in all composite samples without the presence of any intermediate phases. The phonon vibrational modes of the composite samples are detected by Raman spectroscopy over wavenumber regions from 100 to 1000 cm−1 at room temperature. The dielectric constant and dielectric losses are measured over a wide range of frequencies from 1 kHz to 1 MHz at room temperature. Room temperature magnetization measurements confirm the ferromagnetic behavior of all the composite samples. The observed values of coercivity are significantly lower and lie between 9.5 and 49 Oe only, which signifies the soft magnetic behavior of samples. The highest leakage current density value (3.39 × 10−6) has been observed for 50NBT-50NFO composite in I–V measurements. The present study reveals that NBT-NFO composites could be potential lead-free multiferroic composites and provide an alternative for designing environment-friendly devices.

Enhanced piezoelectric properties of (1 -x)BiFe0.98(Zn0.5Hf0.5)0.02O3-xBaTiO3 ceramics near the morphotropic phase boundary.

Here, (1 -x)BiFe0.98(Zn0.5Hf0.5)0.02O3-xBaTiO3 + 1 mol% MnO2 (x = 0.225, 0.250, 0.265, 0.275, 0.285, and 0.300) (BFZH-xBT) ceramics were synthesized using a traditional ceramic sintering technique. A morphotropic phase boundary (MPB) consisting of rhombohedral (R) and tetragonal (T) phases was formed in the BFZH-xBT ceramics when x = 0.285. The suitable content of BT was conducive to enlarge the particle size, improve ferroelectric and piezoelectric properties, and reduce the leakage current density. For the optimal component at x = 0.285, we observed the largest grain size, a lowest leakage current density value of ∼1.93 × 10-5 A cm-2, minimum content of oxygen vacancies, high temperature of 478 °C and the highest piezoelectric coefficient (d33) of 130 pC N-1.

Effects of Tb doping on structural and electrical properties of 47(Ba0.7Ca0.3)TiO3–0.53Ba(Zr0.2Ti0.8)O3 thin films at various annealing temperature by pulsed laser deposition

The ceramic thin films of 47(Ba0.7Ca0.3)TiO3–0.53Ba(Zr0.2Ti0.8)O3 (BCZT) + x (x = 0.2, 0.3, 0.4 and 0.5)mol% Tb were grown on Pt(111)/Si substrates with various annealing temperature by pulsed laser deposition. The XRD spectra confirm that Tb element can enhance the (l10) and (111) orientations in ceramic films. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) images show that Tb-doping can increase particle size effectively. The surface of Tb-doped film annealed at 800℃ is uniform and crack-free, and the average particle size and mean square roughness (RMS) are about 280nm and 4.4nm, respectively. Comparing with pure BCZT, the residual polarization (Pr) of 0.4mol% Tb-doped film annealed at 800℃ increase from 3.6 to 9.8 μC/cm2. Moreover, the leakage current density value of Tb doped films are one order of magnitude (5.33 × 10−9−1.97 × 10−8A/cm2 under 100kV/cm) smaller than those of pure BCZT films (1.02 × 10−7A/cm2).

Ferroelectric properties of Ce3+- doped Aurivillius K0.5Bi4.5Ti4O15 thin films

The effect of Ce3+-ion doping on the structural, electrical and ferroelectric properties of the Aurivillius K0.5Bi4.5Ti4O15 thin films are reported. For the purpose of this study, K0.5Bi4.5Ti4O15 and K0.5Bi4.0Ce0.5Ti4O15 thin films were deposited on Pt(111)/Ti/SiO2/Si(100) substrates by using chemical solution deposition method. Formation of the Aurivillius structure was confirmed through X-ray diffraction and Raman scattering studies. From the experimental results, tremendous improvements in the electrical and the ferroelectric properties were observed for the K0.5Bi4.0Ce0.5Ti4O15 thin film. The ferroelectric polarization-electric field (P-E) hysteresis loops study showed a largely enhanced remnant polarization (2P r ), with a value of 52.8 μC/cm2 for the K0.5Bi4.0Ce0.5Ti4O15 thin film measured at an applied electric field of 595 kV/cm. Furthermore, a low leakage current density value of 1.38×10−8 A/cm2 was measured at an applied electric field of 100 kV/cm for the K0.5Bi4.0Ce0.5Ti4O15 thin film.

Comparative study on doping effects in Bi1−xDyxFe1−yMnyO3 nanoparticles fabricated by sol-gel technique

Abstract We have studied the optical, electrical and magnetic properties of Dy and Mn doped BiFeO3 nanoparticle synthesized by the sol-gel technique. In the doped samples, a transition of crystal structure was demonstrated by XRD. With increasing x from 0.00 to 0.10 and y from 0.00 to 0.05, the optical band gap of Bi1−xDyxFe1−yMnyO3 nanoparticles decreases and can be interpreted by the decreased particle size and the increased internal stress of samples, which caused by Dy, Mn doping. According to the data from X-ray photoelectron spectroscopy, the doping of Dy3+ and Mn2+ can availably restrain the transform from Fe3+ to Fe2+. A small leakage current density and large value of saturation magnetization are observed for the co-doped samples. Therefore, the doping of (Dy, Mn) is an effective mean to strengthen the multiferroic behavior of the nanoparticles.

Electrical and nonlinear current-voltage characteristics of La-doped BiFeO3 ceramics

Multiferroic Bi1-xLaxFeO3(x=0, 0.05, 0.1, 0.2, and 0.3) ceramics with particle sizes of ~67–19nm were prepared by a simple co-precipitation method. The effects of La dopant on the microstructure, giant dielectric response, and electrical properties were investigated. The grain size of Bi1-xLaxFeO3 ceramics significantly decreased with increasing La doping ions. The Bi0.95La0.05FeO3 ceramic exhibited the highest leakage current density value. Interestingly, it strongly decreased as the concentration of La increased. The nonlinear coefficient of La doped BFO slightly decreased with increasing La. This shows a space-charge-limited conduction mechanism, which is involved in low electric field regions for all samples investigated. La substitution significantly enhanced the breakdown field. It was found that the potential barrier height at the grain boundary was slightly reduced from 0.3 to 0.16eV by substitution of La ions. Using impedance spectroscopy analysis, except for the Bi0.7La0.3FeO3 ceramic, the grain boundary resistance at room temperature was affected by dc bias, whereas the grain resistance of all samples was independent of dc bias. This result was well consistent with the variation in low-frequency dielectric constant and loss tangent value due to the effect of dc bias. These results were closely related to the existence of the interfacial polarization at the grain boundary.

Interfacial and electrical properties of Al2O3/HfO2 bilayer deposited by atomic layer deposition on GeON passivated germanium surface

The interfacial and electrical properties of HfO2 (5nm) and Al2O3 (3nm)/HfO2 (5nm) high-k deposited on nitride passivated Ge (100) have been investigated. The XPS spectroscopy and HRTEM were used to study the chemical and interfacial properties of deposited thin films. The stack with only HfO2 shows the suppressed electrical properties such as high value of EOT and density of interface traps. The C-V measurement shows the reduced frequency dispersion with small hysteresis after introduction of 3nm Al2O3 between HfO2 and Ge/GeON. Further, low EOT and Dit have been obtained for GeON/Al2O3/HfO2 gate stack as compared to that of only HfO2 stack. The obtained values of dielectric constant and leakage current density are of ∼24.18 and 1.6×10−6Acm−2 at 1V gate bias, respectively for the stack with Al2O3. Overall, the 3nm Al2O3 capping with GeON improves interfacial and electrical properties of Ge MOS devices.

Electrical, optical, structural and chemical properties of Al2TiO5 films for high-к gate dielectric applications

In search of alternate gate dielectrics for electronic applications, aluminum titanate (Al2TiO5) thin films were deposited at room temperature by DC reactive magnetron sputtering and characterized for their structural, chemical, optical and dielectric properties. To realize the potentiality of these films for gate dielectric applications, we investigated the influence of annealing temperature on these properties. From X-ray photoelectron spectroscopic studies, it has been observed in the as-deposited films that the presence of Al3+ and Ti4+ oxidation states which correspond to Al2O3 and TiO2 respectively. After annealing at 400°C in oxygen ambient, the binding energies of Al 2p, Ti 2p and O 1s were shifted by ~1eV and it remains constant with further increase of annealing temperature from 400 to 800°C. This indicates the formation of an intermediate compound of Al2O3 and TiO2. The extracted Al, Ti and O ratio was 2:1:5 which confirms the formation of Al2TiO5. XRD studies indicate that the as-deposited films were amorphous. After annealing at 400°C, a diffraction peak (200) corresponds to aluminum titanate (Al2TiO5) started appearing, and its intensity increases with increase of annealing temperature. Metal-Oxide-Semiconductor (MOS) capacitors were fabricated and characterized to estimate the dielectric properties of the films. The as-deposited films shows high dielectric constant (к=27.0 at 100kHz) and high leakage current density values (J=0.33A/cm2 at 1MV/cm), high oxide traps (5.5×1013cm−2) and high interface state density (1.5×1013cm−2eV−1). After annealing the films show improved dielectric constant and leakage current density values. The films annealed at 600°C in oxygen ambient show better dielectric constant (к=11.2 at 100kHz) and leakage current density values (J=2.23×10−9A/cm2 at 1MV/cm), low oxide traps (1.4×1012cm−2) and low interface state density (7.1×1011cm−2eV−1) compared with the other films. This suggests that the optimum annealing temperature is required to achieve better device properties.

Structural, dielectric and ferroelectric study of (1−ϕ)(NBT–KNN)–ϕSBexT ceramics

(1−ϕ)(0.93 Na0.5Bi0.5TiO3–0.07K0.5Na0.5NbO3)-ϕSr0.8Bi2.15Ta2O9/(1−ϕ)(NBT–KNN)–ϕSBexT (ϕ=0, 2, 4, 8, 12, 16wt%) ceramic samples were synthesized by conventional solid state reaction route. Secondary phases started developing for higher SBexT content in the (1−ϕ)(NBT–KNN)–ϕSBexT ceramic samples. Decrease of transition temperature (Tm) with the increase of SBexT content in (1−ϕ)(NBT–KNN)–ϕSBexT ceramics was attributed to the increase of internal stress. Remnant polarization (Pr), leakage current density and polarization degradation values reduced with the increase of SBexT content in (1−ϕ)(NBT–KNN)–ϕSBexT ceramic samples. Retention of good ferroelectric properties and enhancement of fatigue-free behavior with the incorporation of SBexT phase in (1−ϕ)(NBT–KNN)–ϕSBexT ceramic samples suggested their usefulness for ferroelectric memory applications.

Structural, electrical, and multiferroic properties of Aurivillius Bi6Fe2(Ti3-xVx)O18+δ thin films prepared by chemical solution deposition

Aurivillius type five-layered V-doped Bi6Fe2(Ti3-xVx)O18+δ (x = 0.00, 0.03, 0.06, and 0.09) thin films were prepared on Pt(111)/Ti/SiO2/Si(100) substrates by using a chemical solution deposition method. All the thin films were crystallized in Aurivillius structures, which have been confirmed by using X-ray diffraction and Raman spectroscopy studies. On comparing the thin films, the Bi6Fe2(Ti2.94V0.06)O18+δ thin film showed the most enhanced electrical and multiferroic properties, with a leakage current density value about four orders of magnitude lower than that of the Bi6Fe2Ti3O18 thin film, for example. All of these thin films showed anti-ferromagnetic hysteresis loops at room temperature. The significant decrease in the concentration of oxygen vacancies and the formation of a stable structure caused by doping with the donor V5+-ion are related to the improved properties in the V-doped Bi6Fe2(Ti3-xVx)O18+δ thin films.

Physical and electrical properties of thermal oxidized Sm2O3 gate oxide thin film on Si substrate: Influence of oxidation durations

Growth of 150nm Sm2O3 films by sputtered pure samarium metal film on silicon substrates and followed by thermal oxidation process in oxygen ambient at 700°C through various oxidation durations (5min, 10min, 15min and 20min) has been carried out. The crystallinity of Sm2O3 film and existence of interfacial layer have been evaluated by X-ray diffraction, Fourier transform infrared and Raman analysis. Crystallite size and microstrain of Sm2O3 were estimated by Williamson–Hall plot analysis. Calculated crystallite size of Sm2O3 from Scherrer equation has similar trend with the value from Williamson–Hall plot. The presence of interfacial layer is supported by composition line scan by energy dispersive X-ray spectroscopy analysis. The surface roughness and surface topography of Sm2O3 film were examined by atomic force microscopy analysis. The electrical characterization revealed that 15min of oxidation durations with smoothest surface has highest breakdown voltage, lowest leakage current density and highest barrier height value.

Microstructures and electrical properties of a Li–ZnO/BiFeO3 double-layered thin film fabricated by a chemical solution deposition method

In this report, the structural, microstructural, electrical, dielectric, and ferroelectric properties of a Zn0.88Li0.12O1-δ/BiFeO3 double-layered thin film are reported. A chemical solution deposition method was used to deposit the Zn0.88Li0.12O1-δ/BiFeO3 double-layered thin film on the Pt(111)/Ti/SiO2/Si(100) substrate. X-ray diffraction and Raman spectroscopic studies indicated the formation of hexagonal wurtzite and rhombohedral perovskite structures for the double-layered thin film. As compared with the BiFeO3 thin film, the Zn0.88Li0.12O1-δ/BiFeO3 thin film exhibited enhanced electrical, dielectric, and ferroelectric properties. The leakage current density value of the Zn0.88Li0.12O1-δ/BiFeO3 double-layered thin film was 1.90×10−4A/cm2 at an applied electric field of 100kV/cm, which was approximately two orders of magnitude lower than that of the BiFeO3 thin film. Moreover, the ferroelectric hysteresis studies revealed a large remnant polarization (2Pr) (11.3μC/cm2) and a low coercive electric field (307kV/cm) for the double-layered thin film.