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With the developments of the electronic industry, efforts to achieve high DC insulating reliability are underway to improve the mean time to failure (MTTF) of multilayer ceramic capacitors (MLCCs). However, there are few studies on appropriate measuring methods to evaluate their different reliability characteristics quantificationally. This study measured different reliability characteristics of BaTiO 3 -based multilayer ceramic capacitors sintered at three different temperatures with highly accelerated life tests (HALTs). Kaplan–Meier survival analysis, two-parameter Weibull fitting, and a new method using a stud genetic algorithm were used to calculate their MTTF in HALT conditions, and the comparison among them was carried out to select a proper fitting way. With the appropriate method, their MTTF at the rated condition was predicted and compared. Their conduction modes were also differentiated to explain their aging sensitivities to temperature and voltage. As a result, a proper way to evaluate the sample's reliability characteristics with a bathtub curve was established, and the best sintering temperature for capacitance that is also the best for reliability at the rated condition was confirmed. Meanwhile, different conducting models of MLCCs were also proved to be related to their insulation stability. [ABSTRACT FROM AUTHOR]

The discharge performance of antiferroelectric (AFE) capacitors is complicated and difficult to simulate due to the nonlinear polarization behavior of AFE. In this work, a nonlinear model for pulsed discharge AFEs was proposed based on a combination of the Preisach model and Kirchhoff's law. The model was driven by the data from first-order reversal curves and direct-current-bias (DC-bias) dielectric test measurements. Thus, the discharge behavior of the AFE can be studied without actual discharge experiments. Specifically, AFE discharge waveforms were calculated and evaluated for different size parameters and external circuit parameters that were conducive to compare the properties of different AFE materials. Moreover, the size effect of the capacitor on the discharge performance was discussed, which should draw the attention of researchers to prevent exaggerated conclusions. As a consequence, this method would fill the gap of AFE discharge simulation. [ABSTRACT FROM AUTHOR]

The capacitors are in rising demand for cryogenic applications. As for now, it still remains an ongoing challenge for simultaneously achieving high energy storage density and cryogenic temperature stability. Herein, the strategy of stable backward phase transition was demonstrated in the antiferroelectric composition of (Pb0.9175La0.055)(Zr0.975Ti0.025)O3. As a result, we achieved high recoverable energy density about 10 J/cm3 with exceptional low-temperature stability from −160 to 25 °C. Multi-layer ceramic capacitors designed for pulse discharge applications also demonstrated high performance in cryogenic conditions, with the peak current fluctuations of less than 4%. Through in situ characterizations using x-ray diffraction, Raman spectra, and transmission electron microscopy, we discovered that the anisotropic structural evolution is responsible for a stable backward phase transition, providing the material with robust stability at cryogenic temperatures. These results offer a good paradigm for improving the temperature stability of antiferroelectric multi-layer capacitors to meet the rigorous demands of energy storage applications. [ABSTRACT FROM AUTHOR]

High polarization of ferroelectric materials has profound research significance and is the decisive factor in the application of energy storage, pyroelectricity, and explosive energy conversion. Herein, in force-electric conversion field, an ultrahigh remanent polarization (51.43 μC/cm2) and record-breaking energy density (4.59 J/cm3) after poling were achieved with a lead-free (1 − x)Bi0.5Na0.5TiO3 − xAgNbO3 [(1 − x)BNT – xAN] relaxor ceramics. The enhancement effect of AgNbO3 on polarization is attributed to the increase in lattice distortion and orientation after poling. Additionally, a significant force-electric conversion effect under hydrostatic pressure (depolarization rate ∼44.8%, 400 MPa) and shock pressure (depolarization rate ∼54.4%, 6.3 GPa) in (1 − x)BNT – xAN was attributed to the pressure-driven ferroelectric/relaxor (FE/RE) phase transition. This work is expected to enlighten the further design of ferroelectric materials with high polarization for pulse power energy conversion application. [ABSTRACT FROM AUTHOR]

This article was originally published online on 15 November 2023 missing an affiliation. All affiliations and identifiers are correct as they appear above. All online versions of this article were corrected on 20 November 2023.By Zhifei Wang; Shiguang Yan; Fei Cao; Zhichao Hong; Yuelong Xiong; Benxia Chen; Chenhong Xu and Genshui WangReported by Author; Author; Author; Author; Author; Author; Author; Author [Extracted from the article]

Practical pyroelectric materials require excellent pyroelectric performance, high depolarization temperature, and good temperature stability. In this work, the microstructure, ferroelectric, dielectric, and pyroelectric properties were studied systematically in (Bi0.5Na0.5)TiO3–0.1%MnCO3 (BNT–Mn) lead-free ceramics. It is observed that the pyroelectric coefficient p reaches 2.90 × 10−4 C m−2 K−1 at room temperature in the samples. Due to the low dielectric constant (291) and dielectric loss (0.010), the figures of merit (FoMs) Fi, Fv, and FD are as high as 1.03 × 10−10 m/V, 4.05 × 10−2 m2/C, and 1.86 × 10−5 Pa−1/2, measured at 1 kHz. With the increase in temperature, the p and FoMs change slightly, showing good temperature stability. More importantly, a relatively high depolarization temperature of 205 °C is achieved, which should help deliver reliable operation in practice. In general, all performances reveal that BNT–Mn ceramics are expected to pave the way for uncooled infrared detector applications. [ABSTRACT FROM AUTHOR]

The scaling behaviors of dynamic hysteresis were investigated in serial rhombohedral Nb-doped Pb(Zr1-xTix)O3 (PZT) bulk ceramics as a function of frequency (f) and field amplitude (E0). Three distinct regions were plotted including linear loops, minor loops, and saturated loops with an increase of E0. When the external fields were over ∼1.5 times of coercive field (Ec), the scaling relations of saturated loops for these PZT ceramics could be expressed with an identical form as hysteresis area ∝ f 0.01E00.10, which indicated that similar ferroelectric systems with different compositions could display a uniform scaling law under high-E0 and low-f regions. [ABSTRACT FROM AUTHOR]

The temperature scaling of the ferroelectric hysteresis was first investigated in (K,Na)NbO3 films grown on SrRuO3/SrTiO3 over a temperature range from 100 K to 340 K. The power-law temperature scaling relations were obtained for , Pr, and Ec in the two distinguished temperature regions, separated by T ∼ 245 K. It was observed that and Pr had a similar temperature dependence, compared with Ec. With increasing T, and Pr decreased in the first region, and increased in the second region. While Ec decreased in the whole temperature range, but with different decrease rate in the two temperature regions. [ABSTRACT FROM AUTHOR]

In the practical application of capacitors, especially in pulsed application, recoverable energy is a key parameter, which represents the ability to store energy. However, many existing evaluation methods for energy storage calculation have not been systematically implemented and comprehensively understood. In this work, four methods were applied to calculate the energy storage in linear, ferroelectric, and antiferroelectric capacitors. All methods were valid when the linear capacitor was examined. In terms of the ferroelectric capacitor, the method of equivalent parameter using DC-bias capacitance was infeasible under the high voltage owing to a massive decrease in field-dependent capacitance. As for the antiferroelectric capacitor with noticeable hysteresis, the maximum of energy storage was obtained by the method of integration of hysteresis loop, while the lower one was obtained in the fast discharge condition by the method of integration of UI (product of voltage and current). In summary, for different materials, both test conditions and calculation methods should be considered to get accurate energy storage, which best fits the working conditions. [ABSTRACT FROM AUTHOR]

We report the electric-field-induced ferroelectric (FEIN) to antiferroelectric (AFE) phase transition that is tuned by the poling temperatures in 0.89Bi0.5Na0.5TiO3-0.06BaTiO3-0.05K0.5Na0.5NbO3 (0.89BNT-0.06BT-0.05KNN) ceramics. Phase transition and pyroelectric behaviors of the ceramics were investigated as functions of temperature and electric field. Pyroelectric coefficient peaks of (3 ∼ 6.5) × 10-8 C cm-2 K-1 are detected at about 10 °C above the poling temperatures for the samples poled at different temperatures. The poling temperature tuned pyroelectric behaviors are attributed to the FEIN to AFE phase transition when the temperature increases. [ABSTRACT FROM AUTHOR]

The charge-discharge properties of lanthanum- and niobium-doped lead zirconate stannate titanate ceramics were investigated by directly measuring the hysteresis loops, dielectric constants under a dc bias field, and pulse discharge current-time curves after varying charge-discharge circulations. It was found that there was no significant effect of the charge-discharge circulation on these properties. The first pulse current peak reached 1.8 kA at 40 kV/cm, and most of the stored charge was released in 500 ns. These results show that the obtained slanted ceramics with high energy density can withstand hundreds of charge-discharge circulations and are very promising for pulse capacitor applications. [ABSTRACT FROM AUTHOR]

Well-defined polarization-electric field double hysteresis loops are rarely observed in pure NaNbO3 (NN) ceramics due to the metastability of the field-induced ferroelectric phase. In order to stabilize the antiferroelectric phase, various ABO3-type binary oxides were incorporated into a NaNbO3 ceramic, where the B-site is occupied with transition elements. In this work, CaSnO3 was chosen to construct the NaNbO3-based solid solution by reducing the Goldschmidt tolerance factor and ionic polarizability. X-ray diffraction patterns, transmission electron microscopy images, and Raman spectra indicate enhanced antiferroelectricity. Typical double hysteresis loops were also observed from polarization-electric field measurements in ambient conditions with slightly weakened maximum polarization as the content of CaSnO3 increased. Our results reveal the generality of this strategy and pave the way for various applications involving high-power energy for NaNbO3-based ceramics. [ABSTRACT FROM AUTHOR]

To support practical infrared detector applications, pyroelectric ceramics should exhibit excellent pyroelectric performances, high depolarization temperatures, and good thermal stabilities. In this study, the pyroelectric properties, depolarization behaviors, and thermal stabilities of tetragonal 0.8Bi0.5Na0.5TiO3–0.2BaTiO3 (0.8BNT–0.2BT) ceramics are studied systematically. The samples exhibit high depolarization temperatures (∼209 °C) and excellent thermal stabilities. More importantly, they display high pyroelectric coefficients (p = 2.42 × 10−8 C cm−2 K−1), as well as high voltage responsivity (Fv = 2.68 × 10−2 m2 C−1) and specific detectivity (Fd = 1.53 × 10−5 Pa−1/2) figures of merit at room temperature and 1 kHz. The overall properties of tetragonal 0.8BNT–0.2BT ceramics indicate their potential for application in infrared detectors. [ABSTRACT FROM AUTHOR]

Dielectric relaxation and magnetodielectric (MD) effects were observed in 0.36BiScO3-0.64PbTiO3/La0.7Sr0.3MnO3 thin films. The universal dielectric response and distribution of relaxation time modifications were introduced into the Maxwell-Wagner (MW) model. Based on modified MW model, the negative MD response at low frequencies was attributed to magnetostriction of La0.7Sr0.3MnO3, while the large positive response at high frequencies mainly to the magnetoresistance of La0.7Sr0.3MnO3, and these two factors canceled each other out at intermediate frequencies. Moreover, a giant room temperature MD response of 9.5% was observed, and the linear MD response at 52 kHz was ascribed to the linear magnetoresistance effects. [ABSTRACT FROM AUTHOR]

The ferroelectric hysteresis loops of 63PbTiO3-37BiScO3 ceramics were measured under sinusoidal electric fields in the range of frequency from 0.1 to 100 Hz and field from 5 to 55 kV/cm. The fitting results showed two linear relations existed between the logarithm of hysteresis area and the logarithm of the amplitude of field E0 in the first and third field region. In the second region, no linear relation existed due to polarization reversal. These three-stage behaviors were distinct from the existing two-stage behaviors. The slopes in the third stage increase with the increasing of frequency, which can be attributed to dielectric loss under high frequency. [ABSTRACT FROM AUTHOR]

The temperature scaling relations of the dynamic hysteresis were investigated in Zr-rich lead zirconate titanate (PZT) bulk ceramics. At each relation curve, there is a discontinuous district corresponding to the low- and high-temperature phase transitions. The temperatures are divided into low-T region and high-T region. At each temperature region, three power-law scaling relations were obtained for hysteresis area , coercivity Ec, and remnant polarization Pr with T, respectively. The six temperature scaling relations are field dependent and the simplified forms are different from the results obtained from the soft and hard PZT ceramics. [ABSTRACT FROM AUTHOR]

The pulsed power supply that generates megawatts of electrical power has drawn important attention for many decades. Despite that the large energy output has been obtained in lead-containing materials such as Pb(Zr0.95Ti0.05)O3 (PZT95/5) ceramics, lead-free ferroelectric candidates are highly desired due to the environmental concerns. In this work, we report the depolarization behavior of lead-free ternary 0.99[0.98(Bi0.5Na0.5)(Ti0.995Mn0.005)O3-0.02BiAlO3]-0.01NaNbO3 ferroelectric ceramics under shock wave compression. A current profile with a maximum value of ∼25 A and a FWHM of ∼2.3 μs was obtained. Particularly, the poled BNT-BA-0.01NN ceramics were almost completely depolarized under high strain rate loading, releasing a high charge density J of 38 μC/cm2. The released J was approximately 96% of thermal-induced charge density (∼40 μC/cm2), which was 18% higher than that of PZT95/5 ceramics. The shock-induced depolarization mechanism can be attributed to the ferroelectric-ergodic relaxor phase transition. These results reveal the BNT-based ceramics as promising candidates for pulsed power applications. [ABSTRACT FROM AUTHOR]

Hafnium oxide based ferroelectric thin films have shown potential as a promising alternative material for non-volatile memory applications. This work reports the switching stability of a Si-doped HfO2 film under bipolar pulsed-field operation. High field cycling causes a 'wake-up' in virgin 'pinched' polarization hysteresis loops, demonstrated by an enhancement in remanent polarization and a shift of negative coercive voltage. The rate of wake-up is accelerated by either reducing the frequency or increasing the amplitude of the cycling field. We suggest de-pinning of domains due to reduction of the defect concentration at bottom electrode interface as origin of the wake-up. [ABSTRACT FROM AUTHOR]

The current decay characteristic in the time domain is studied in Y3+ and Mn2+ modified Ba0.67Sr0.33TiO3 ceramics under different temperatures (25 °C-213 °C) and voltage stresses (0 V-800 V). The decay of the current is correlated with the overlapping of the relaxation process and leakage current. With respect to the inherent remarkable dielectric nonlinearity, a simple method through curve fitting is derived to differentiate these two currents. Two mechanisms of the relaxation process are proposed: a distribution of the potential barriers mode around room temperature and an electron injection mode at the elevated temperature of 110 °C. [ABSTRACT FROM AUTHOR]

Polarization switching and energy storage properties of highly (100) oriented antiferroelectric (AFE) (Pb,La)(Zr,Ti)O3 thin films (≤250 nm) deposited via a sol-gel process with both LaNiO3 and Pt top electrodes were investigated. By using LaNiO3 top electrodes, the energy density as well as energy efficiency can be enhanced by 4.6 J/cm3 and 11%, respectively. Furthermore, the films with LaNiO3 top electrodes are more capable of providing high energy density over a wide temperature regime above room temperature compared to Pt. This work clearly highlights that oxide top electrodes can greatly improve the energy storage performance of antiferroelectric thin film capacitors. [ABSTRACT FROM AUTHOR]

Pyroelectric response mechanism of Ba0.70Sr0.30TiO3 ceramics under dielectric bolometer (DB) mode was investigated by dielectric and pyroelectric properties measurement. The variations of total, intrinsic, and induced pyroelectric coefficients (ptot, pint, pind) with temperatures and bias fields were analyzed. pint plays the dominant role to ptot through most of the temperature range and pind will be slightly higher than pint above T0. The essence of the enhancing effect of DC bias field on pyroelectric coefficient can be attributed to the high value of pint. This mechanism is useful for the pyroelectric materials (DB mode) applications. [ABSTRACT FROM AUTHOR]

Antiferroelectric Pb(Zr, Nb, Ti)O3 (PZNT) films were deposited via a sol-gel process on Pt(111)/Ti/SiO2/Si, LaNiO3- and La0.5Sr0.5CoO3-buffered Si substrate. The scaling behavior of the energy density W of antiferroelectric films was investigated. The scaling behavior of W against frequency f of PZNT on LaNiO3-buffered Si takes the form of W ∝ f0.08, which differs significantly from that form of W ∝ f-0.14 of PZNT on La0.5Sr0.5CoO3-buffered Si. This indicates that the scaling relations of W vary substantially as bottom electrodes change and might be closely related to the variation of nonuniform strain field and depolarization field within the AFE films. [ABSTRACT FROM AUTHOR]

The ferroelectric Ba0.6Sr0.4TiO3 (BST) and dielectric MgO composites with three different structures: columnar, layered, and spherical inclusion were prepared by spark plasma sintering (SPS). The microstructure and dielectric properties were investigated. Results show that the columnar composite exhibits an appreciable tunability (44.3%) as high as that of pure BST while the permittivity has been reduced from 5872 to 3998 at 10 kHz at room temperature, leading to a reduction of permittivity without deterioration of tunability in the bulk ceramics. This is a feasible way to balance the permittivity and the tunability, which is very promising for tunable devices application. [ABSTRACT FROM AUTHOR]

The effectiveness of ZrSiN/Zr bilayered films to serve as diffusion barriers in Cu/Si contacts has been investigated. Annealing studies for Cu/ZrSiN/Zr/Si contact systems were carried out in N2/H2(10%) ambient. X-ray diffraction data suggest that Cu film has preferential (111) crystal orientation and Cu silicide cannot be observed up to 700 °C. Scanning electron microscopy micrographs show that the Cu film was integrated and free from agglomeration after annealing at 700 °C. Auger electron spectroscopy depth profiles of the Cu/ZrSiN(10 nm)/Zr(20 nm)/Si samples have no noticeable change except Zr silicide grows with annealing temperature up to 700 °C. The results indicate excellent barrier property for ZrSiN(10 nm)/Zr(20 nm) bilayer structure for Cu metallization. [ABSTRACT FROM AUTHOR]

Several 0.97PbZrO3–0.03Ba(Mg1/3Nb2/3)O3 (0.97PZ–0.03BMN) ceramics were prepared via the columbite precursor method. Their microstructures and pressure-dependent ferroelectric and depolarization performances were then studied. The X-ray diffraction patterns of ground and fresh samples indicate that a main rhombohedral symmetry crystal structure is present in the bulk and that it sits alongside a trace quantity of an orthorhombic antiferroelectric phase that results from the effect of grinding on the surface. The remanent polarization (Pr) of the 0.97PZ–0.03BMN reached 32.4 μC/cm2 at 4.5 kV/mm and ambient pressure. In an in situ pressure-induced current measurement, more than 91% of the retained Pr of the pre-poled sample was released when the pressure was increased from 194 MPa to 238 MPa. That this pressure-driven depolarization should be attributed to the pressure-induced ferroelectric–antiferroelectric phase transition is supported by the emergence of double P–E loops at high hydrostatic pressures. Moreover, the 0.97PZ-0.03BMN ceramics exhibit no temperature-induced phase transitions and little related polarization loss up to 125 °C, which suggests that Pr has excellent thermal stability. The sharp depolarization behavior at low pressures and excellent temperature stability reveal that our 0.97PZ–0.03BMN ceramics exhibit superior performances in mechanical–electrical energy conversion applications. [ABSTRACT FROM AUTHOR]

Cax(Sr0.5Ba0.5)1-xNb2O6 [CSBN(x), x = 0.00, 0.10, 0.15, and 0.20] lead-Free ceramics were prepared by a traditional solid-state reaction technique. Dielectric, ferroelectric, and pyroelectric properties of CSBN(x) lead-Free ceramics were systematically investigated. The pyroelectric properties of CSBN(x) have been enhanced remarkably due to Ca addition and reached the maximum values at x = 0.15, with pyroelectric coefficient of 3.61 × 10-8 C/cm2 K and pyroelectric figure of merit of Fi = 172 pm/V, Fv = 0.021 m2/C, and Fd = 11.5 μPa-1/2, which are superior to other lead-free ferroelectric ceramics. These results indicate the potential of CSBN(x) ceramics for infrared detector applications. [ABSTRACT FROM AUTHOR]

Solar chimney power plant (SCPP) with a long life span is a promising large-scale solar thermal utilization technology. This paper performs an economic analysis for the conventional solar chimney power plant (CSCPP) and the sloped solar chimney power plant (SSCPP) in Northwest China. Cash flows are influenced by many factors including the investment, the payback period, the inflation rate, and the sale price of solar electricity. The techno-economic analyses of the CSCPPs and SSCPPs are performed taking Lanzhou, China as a case study. The results show that the SCPP investment is influenced by both its configuration and the material price, and the SSCPP is more cost-effective than the CSCPP during the system life span. In addition, the SCPP with large power capacity holds good competitiveness with the conventional fossil fuel combustion plants. The economic evaluation of building SCPPs in Northwest China is of high significance considering the local abundant solar radiation, favorable government policy, and under-developing economics. [ABSTRACT FROM AUTHOR]

(Pb0.325Sr0.675)TiO3 (PST) ceramics were prepared by a traditional solid-state reaction technique. The dielectric and enhanced pyroelectric properties of PST ceramics were investigated under a DC bias field. The dielectric permittivity and dielectric loss of PST ceramics at Curie temperature were 2.97 × 10-4 and 0.006 without DC bias field, respectively. With a DC electric field of 0-500 V/mm, the maximum pyroelectric coefficient and the largest figure of merit (Fd) of PST ceramics were obtained, about 60 × 10-8 C cm-2 K-1 and 26 × 10-5 Pa-1/2, respectively. PST ceramics with such superior electric field enhanced pyroelectric properties have the potential for uncooled focal plane array detectors application. [ABSTRACT FROM AUTHOR]