Double Hysteresis Loops Research Articles

Large electric-field induced strain in new ternary lead-free piezoelectric solid solution Na0.5Bi0.5TiO3-BaTiO3-Sr (Ta0.5Al0.5) O3

Ternary lead-free piezoelectric ceramics Na0.5Bi0.5TiO3-BaTiO3-Sr(Ta0.5Al0.5)O3 were synthesized via conventional solid-phase synthesis. All samples exhibited pure perovskite structure, indicating that Sr(Ta0.5Al0.5)O3 can be solidified into the Na0.5Bi0.5TiO3-BaTiO3 perovskite structure. The remanent polarization Pr and coercive field EC of the undoped Na0.5Bi0.5TiO3-BaTiO3 ceramic were Pr∼35.23µC/cm2 and EC∼42.46 kV/cm, respectively. The introduction of Sr(Ta0.5Al0.5)O3 sharply affected the ferroelectric properties of the substrate Na0.5Bi0.5TiO3-BaTiO3 ceramics. Increase in the content of Sr(Ta0.5Al0.5)O3 induces transition of this ternary system from a ferroelectric phase to an antiferroelectric-like phase, accompanied by double hysteresis loops in the 0.003SAT, 0.005SAT, and 0.01SAT components. The high dielectric constant ε′∼4300 was obtained for the 0.005SAT composition. The 0.015SAT composition yielded the maximum bipolar electric-field strain S (%) ∼0.53 % and high-field piezoelectric strain coefficient d33*∼ 996 pm/V. This result shows that a ternary Na0.5Bi0.5TiO3-BaTiO3-Sr(Ta0.5Al0.5)O3 solid solution is a promising alternative to lead-based piezoelectric materials in the field of high-performance actuators.

Antiferroelectric-like double hysteresis loops in Ag-doped K0.5 Na0.5NbO3 ceramics

In this work, we report the effect of Ag+ doping on the microstructure, dielectric, ferroelectric, piezoelectric, and energy storage properties of the K0.5Na0.5NbO3 (KNN) ceramics for which (K0.5Na0.5)(1-x)AgxNbO3 (KNN-xAg) ceramics with x = 0, 0.01, 0.02 and 0.03 were prepared by the conventional solid-state method. The substitution of Ag+ changes the microstructure of KNN from inhomogeneous bimodal grain distribution to homogeneous densely packed grains with an average grain size of 0.5–2.25 μm. The phase transition (TC) of KNN shifts towards the lower temperature side with Ag+ doping. Antiferroelectric-type double PE loops were observed in Ag-doped KNN ceramics at room temperature, which has improved the energy storage and piezoelectric properties of KNN. For ceramics poled at 2 kV/mm for 30 min, a d33 value of ∼149 pC/N and kp ∼0.41 were obtained. These enhanced properties in Ag-doped KNN are due to the occurrence of double polarization hysteresis loops.

Multiferroic Properties of Pure and Ion‐Doped BiCrO3 Bulk and Thin Films

The multiferroic properties of BiCrO 3 (BCO) bulk and thin films are investigated for the first time using a microscopic model. The influence of ion doping on the multiferroic properties of BCO is also studied because the doping process changes the physical properties and can be used for potential applications in magnetoelectronic devices. The magnetization M increases by Mn and decreases by Ga-ion doping whereas the Néel temperature T N decreases in both cases. There are some discrepancies by polarization whether it is ferroelectric or antiferroelectric. It is shown that bulk pure BCO is antiferroelectric because the electric field dependence of polarization P shows a double hysteresis loop and the dielectric constant has no anomalies at T N . In Ga-, Mn- or Ti-doped BCO a ferroelectric polarization appears. The specific heat shows a peak at T N for BCO. By Ga doping, this peak vanishes with increasing x. The multiferroic behavior of BCO is demonstrated in the magnetic field dependence of the dielectric constant. In BCO thin films, ferroelectric and ferromagnetic behavior is observed.

Domain switching dynamics in topological antiferroelectric vortex domains

Hexagonal manganites can exhibit intriguing ferroelectric (FE) and partially undistorted antiferroelectric (PUA) ${Z}_{6}$-vortex domain patterns, which are dual to each other. Due to the same origin, it can be expected that the two real-space topological structures will behave the same way in terms of nonelectric properties such as domain topology and scaling of vortex density. However, their electric properties would be very different from each other, while these differences are rarely understood due to the absence of investigation on PUA ${Z}_{6}$-vortex domain patterns. In this work, we study the response of the PUA $P\text{\ensuremath{-}}3c1$ structure to external electric fields and the switching dynamics of PUA ${Z}_{6}$-vortex domain patterns by combining Landau theory and phase-field simulations. We find that an electric field along the $c$ axis can tune the trimerizing tilting angle of the ${\mathrm{MnO}}_{5}$ trigonal bipyramids in PUA $P\text{\ensuremath{-}}3c1$ structure while no such effect is present in the FE $P{6}_{3}cm$ structure. As a result, a continuous phase transition sequence $P\text{\ensuremath{-}}3c1\ensuremath{\rightarrow}P3c1\ensuremath{\rightarrow}P{6}_{3}cm$ can be induced. For both the PUA ${Z}_{6}$-vortex domain pattern and the single PUA domain, the variation of the total polarization with a sinusoidal electric field manifests as a double-hysteresis loop. We find out that this is because the transition from $P{6}_{3}cm$ back to $P3c1$ is a first-order transition. The switching dynamics of PUA ${Z}_{6}$-vortex domain patterns is found to be very different from that observed on FE ${Z}_{6}$-vortex domain patterns. Our results advance the understanding of real-space topological structures and suggest that the PUA $P\text{\ensuremath{-}}3c1$ structure may exhibit excellent performance in dielectric energy storage.

Hysteresis and return point memory in the random-field Blume-Capel model.

We study the zero-temperature steady-state of the random-field Blume-Capel model with spin-flip Glauber dynamics on a random regular graph. The magnetization m as a function of the external field H is observed to have double hysteresis loops with a return point memory. We also solve the model on a Bethe lattice in the approximation that the spin relaxation dynamics is abelian and find good agreement between simulations on random regular graphs and Bethe lattice calculations for negative values of H.

Preparation and electrical properties of Ba0.85Ca0.15Zr0.1Ti0.9O3 ceramics by the doping of Mn ions

A series of Ba0.85Ca0.15Zr0.1(Ti1-xMnx)0.9O3 (x = 0%, 2%, 4% and 8%; Ba0.85Ca0.15Zr0.1Ti0.9O3 abbreviated as BCZT) ceramics were prepared via the sol-gel method. No secondary phase was detected in XRD patterns, indicating that Mn entered into the unit cell to form a solid solution. The microstructures for Mn-doped BCZT ceramics show Mn can inhibit the growth of BCZT grain size. The dependence of dielectric constant on temperature shows that the Curie temperature decreases and the degree of dispersed phase increases with the increase of the doping amount. When the doping amount is x = 2% and x = 4%, the hysteresis loop shows a significant shrinkage, the remanent polarization is significantly reduced, and the shrinkage is more severe under high electric field. The double hysteresis loops appeared, indicating that the hysteresis loop of BCZT ceramic can be adjusted by doping a certain amount of Mn ions. The sample of x = 4% shows an energy density of 0.18 J/cm3 and an energy efficiency of 58.5%.

Stabilized piezoelectricity upon ferro-ferro phase transition achieved by aging induced domain memory effect in acceptor doped lead-free ceramics

Strong temperature dependence of piezoelectricity (d33) attributed to morphotropic/polymorphic transition at room temperature limits the practical application of high performance lead-free piezoceramics. This work found aging induced domain memory effect is effective stabilizing d33 through ferroelectric orthorhombic (O)-tetragonal (T) transition together with a large room temperature d33 (d33@RT) in Mn doped lead-free 55Ba(Ti0.8Zr0.2)O3-45(Ba0.7Ca0.3)TiO3 piezoceramics: 23.2% d33 variation through O-T transition and a large d33@RT ∼ 323 pC/N for doped one when compared with those of undoped one (96.8% d33 variation and d33@RT ∼ 278 pC/N). Restoring force induced by defect dipoles according to the symmetry conforming short-range ordering principle has been demonstrated with internal bias field and double hysteresis loops, while the outcoming domain memory effect, responsible for the stabilized behaviors, has been revealed with transmission electron microscopy observation and phase-field simulation. Thus, aging induced domain memory effect is effective achieving stabilized behaviors and large d33@RT simultaneously.

Antiferroelectricity of NaNbO3: Single‐crystal experimental study and first‐principles calculation

AbstractSimilar to the canonical antiferroelectric (AFE) compound PbZrO3 in Pb(Zr,Ti)O3 solid‐solutions, the presence of double hysteresis loops and that of electric field–induced phase transitions are important characteristics of NaNbO3 AFE materials; yet the phase transition behavior in the latter system is typically irreversible with the related mechanisms not fully understood. Here, we explore the phase transition mechanism of ferroelectric and AFE phases in NaNbO3 based on measurements of single crystals with different directions in conjunction with density‐functional theory (DFT) calculations. The tilting and distortion behaviors of the [NbO6] octahedra are explained by DFT, and the ion displacement in the lattice is traced. The tilting and distortion behaviors of the [NbO6] octahedra with different orientations are compared. We confirm that the tilt and distortion of the [NbO6] octahedra along the [1 1 1] direction is the main reason to improve the stability of AFE phase. This conclusion is verified by the experimental characterizations of large‐size NaNbO3 single crystals successfully obtained in this study.

Ferroelectric properties and large electric field-induced strain of Eu3+-doped Na0.5Bi0.5TiO3–BaTiO3 lead-free ceramics

Eu3+-doped lead-free piezoelectric ceramics, 0.937Na0.5Bi0.5−xEuxTiO3-0.063BaTiO3 (abbreviated as NBExT-BT, where x = 0, 0.003, 0.005, 0.01, 0.013, 0.015, 0.017, and 0.02), were synthesized using a conventional solid-state synthesis method. All the component samples were crystallized in a pure perovskite structure without a secondary phase. The introduction of Eu3+ caused the evident variation of the dielectric, ferroelectric and luminescence properties. The remanent polarization and coercive field of the pure NBT-BT are Pr ∼29.24 μC/cm2, Ec∼39.33 kV/cm, respectively. The maximum of the remanent polarization Pr of ∼38.02 μC/cm2 at room temperature and the highest dielectric constant of 6899 with a frequency of 1 kHz were obtained for NBE0.003T-BT. The maximum bipolar strain Smax of ∼0.91% and the minimum of coercive field Ec ∼18.45 kV/cm were achieved by the NBE0.015T-BT, resulting from the formation of a double hysteresis loop. For all the components, Eu3+ doping stabilized the antiferroelectric phenomenon at high temperature. Furthermore, the polarized NBE0.015T-BT had the strongest fluorescence luminescence intensity as well as a fluorescence lifetime reaching 785.98 μs.

CoFeVSb: A promising candidate for spin valve and thermoelectric applications

We report a combined theoretical and experimental study of a novel quaternary Heusler system CoFeVSb from the view point of room temperature spintronics and thermoelectric applications. It crystallizes in cubic structure with small DO$_3$-type disorder. The presence of disorder is confirmed by room temperature synchrotron X-ray diffraction(XRD) and extended X-ray absorption fine structure (EXAFS) measurements. Magnetization data reveal high ordering temperature with a saturation magnetization of 2.2 $\mu_B$/f.u. Resistivity measurements reflect half-metallic nature. Double hysteresis loop along with asymmetry in the magnetoresistance(MR) data reveals room temperature spin-valve feature, which remains stable even at 300 K. Hall measurements show anomalous behavior with significant contribution from intrinsic Berry phase. This compound also large room temperature power factor ($\sim0.62$ mWatt/m/K$^{2}$) and ultra low lattice thermal conductivity ($\sim0.4$ W/m/K), making it a promising candidate for thermoelectric application. Ab-initio calculations suggest weak half-metallic behavior and reduced magnetization (in agreement with experiment) in presence of DO$_3$ disorder. We have also found an energetically competing ferromagnetic FM)/antiferromagnetic (AFM) interface structure within an otherwise FM matrix: one of the prerequisites for spin valve behavior. Coexistence of so many promising features in a single system is rare, and hence CoFeVSb gives a fertile platform to explore numerous applications in future.

Intrinsic 90° charged domain wall and its effects on ferroelectric properties

The domain is an important characteristic of ferroelectric materials, and the type of domain can have significant effects on the performance of ferroelectric materials. In particular, the unique wake-up and fatigue effects of Hf0.5Zr0.5O2 (HZO) films severely restrict improvements in terms of film performance. Recently, using integrated differential phase contrast (iDPC) scanning transmission electron microscopy (STEM) imaging, we observed the existence of intrinsic tail-to-tail 90° domain structures, charged domain walls (CDWs), and polarization relaxation on the TiN/HZO/TiN interfaces of HZO films. Based on this experimental investigation, we establish a phase-field model of the tail-to-tail 90°CDWs based on the time-dependent Ginzburg–Landau equation. In our model, the tail-to-tail 90°CDW affects the mesoscopic domain switching through a built-in electric field, which, in turn, affects the macroscopic ferroelectric properties of the thin film. The following conclusions are drawn: (a) the CDWs that are distributed horizontally or vertically along the thickness of the film cause a A-wake-up effect (antiferroelectric-like wake-up) with double hysteresis loops or a S-wake-up effect (spindle-like wake-up), with thick portions in the middle and both ends points of the hysteresis loop; (b) the S-wake-up caused by the CDWs distributed along the thickness of the film performs badly in fatigue tests and is easier to break down. The model proposed herein reveals the mechanism of the wake-up effect in hafnium oxide-based ferroelectric films. It provides a theoretical basis for the development of a new type of hafnium oxide-based ferroelectric memory system.

Ultrahigh energy storage density and superior discharge power density in a novel antiferroelectric lead hafnate

Dielectric capacitors have been widely applied to pulse charge-discharge systems with medium energy density and high power density. In this work, (Pb1-3x/2Lax)Hf0.96Ti0·04O3 (PLHT) antiferroelectric (AFE) ceramics were synthesized by a solid-state solution. The field-induced AFE to ferroelectric transitions with double polarization-electric field hysteresis loops were observed for all studied components. The energy storage efficiency of PLHT ceramics was significantly improved by doping La3+. The sample of x = 0.05 (PLHT-0.05) exhibits excellent energy storage properties with a record-high recoverable energy storage density of 11.2 J/cm3, and a high energy efficiency of 88.9% achieved at an electric field of 360 kV/cm. The ceramic exhibits superior frequency and thermal stability against external environmental change. Besides, a record high discharge energy density (8.51 J/cm3) with an ultrafast discharge rate (t0.9<211 ns) was obtained under 360 kV/cm at room temperature in PLHT-0.05 ceramic. Underdamped discharge test shows the sample achieves an ultrahigh current density of 2098 A/cm2 and a giant power density of 378 MW/cm3, suggesting a significant advantage compared with the previously reported ceramic systems. The significant improvement implies the PLHT AFE ceramics can provide a realistic solution for high-power energy storage capacitors.

Sm-Eu Co-Doped BiFeO3 Nanoparticles With Superabsorption and Electrochemical Oxygen Evolution Reaction

Bi0.95Sm0.05Fe1−xEuxO3 (x = 0, 0.05, 0.10, 0.15) nanoparticles were prepared via a two-solvent sol–gel method. The X-ray diffraction (XRD) and Raman results suggested that the main phase of the samples gradually evolved from perovskite phase R3c to orthorhombic phase Pbnm with increasing Eu content and that the optical band gap gradually narrowed from 2.09 to 1.70 eV. Along with the structural change, the ferromagnetic properties were transformed, and interesting double hysteresis loops were observed for the sample where x = 0.1. All the bismuth ferrite (BFO) samples demonstrated extremely strong adsorbability, with the adsorption rate of refractory methyl orange reaching 90% in 5 min. These samples also exhibited superior oxygen evolution reaction (OER) performance, with a desirable onset potential of approximately 1.50 V vs. RHE. For the sample where x = 0.15, to support a current density of 100 mA/cm2, an overpotential of only 294 mV was required, which is much better than that of pure Ni foam (330 mV). More experiments are needed to verify and explore the source and mechanism of the OER performance.

Anisotropic effect of dipolar interaction in ordered ensembles of nanoparticles

We implement extensive computer simulations to investigate the hysteresis characteristics in the ordered arrays (lx × ly) of magnetic nanoparticles as a function of aspect ratio Ar = ly/lx, dipolar interaction strength hd, and external magnetic field directions. We have considered the aligned anisotropy case, α is the orientational angle. It provides an elegant en route to unearth the explicit role of anisotropy and dipolar interaction on the hysteresis response in such a versatile system. The superparamagnetic character is dominant with weak dipolar interaction (hd ≤ 0.2), resulting in the minimal hysteresis loop area. Remarkably, the double-loop hysteresis emerges even with moderate interaction strength (hd ≈ 0.4), reminiscent of antiferromagnetic coupling. These features are strongly dependent on α and Ar. Interestingly, the hysteresis loop area increases with hd, provided Ar is enormous, and the external magnetic field is along the y-direction. The coercive field μoHc, remanent magnetization Mr, and the heat dissipation EH also depend strongly on these parameters. Irrespective of the external field direction and weak dipolar interaction (hd ≤ 0.4), there is an increase in μoHc with hd for a fixed α and Ar ≤ 4.0. The dipolar interaction also elevates Mr as long as Ar is huge and the field is along the y-direction. EH is minimal for negligible and weak dipolar interaction, irrespective of Ar, α, and the field directions. Notably, the magnetic interaction enhances EH if Ar is enormous and the magnetic field is along the long axis of the system. These results are beneficial in various applications of interest such as digital data storage and spintronics. (a) Schematic of the two-dimensional array of nanoparticles. The variation of heat dissipation EH as a function of dipolar interaction strength and anisotropy axis orientation is shown in (b)-(d). The magnetic field is applied along the x-direction in (b). In contrast, the magnetic field is applied along y-direction in (c) and (d).

NaNbO3 modulated phase transition behavior and antiferroelectric stability evolution in 0.88(Bi0.5Na0.5)TiO3-0.12BaTiO3 lead-free ceramics

Giant strains in (Bi0.5Na0.5)TiO3 based ceramics are usually attributed to electric field induced nonpolar to polar phase transition. Whether it is an ergodic relaxor R3c/P4mm ferroelectric (FE) to long-range ordered FE phase transformation or a reversible P4bm antiferroelectric (AFE) to FE phase transition is still unclear. Herein, lead-free (0.88-x)(Bi0.5Na0.5)TiO3-0.12BaTiO3-xNaNbO3 ceramics exhibit a composition-modulated FE tetragonal P4mm to relaxor AFE tetragonal P4bm phase transition, in which double hysteresis loop, sprout-shaped S-E curves, near-zero quasi-static d33 together with a large volume change suggest the AFE characteristics of P4bm phase. An interesting finding is that the reversibility of field-induced AFE P4bm phase to FE P4mm phase transition strongly depends on the NN content, from being completely irreversible at x = 0.01–0.02, to partially reversible at x = 0.03–0.05, and finally to completely reversible at x = 0.06–0.08. It is indicated that the variation of reversibility should be attributed to the change of relative free energy caused by decreasing the FE to AFE phase transition temperature with increasing the NN content.

Bimodal-random field Blume–Capel model in the cluster variation method

The outcome of the bimodal random magnetic field acting up or down along the z-axis on the spins of spin-1 with equal probability is investigated by using the lowest approximation of the cluster-variation method in the Blume–Capel model. The equal probability, p=12, causes the model to give phase transitions of the form either second- or first-order. The phase diagrams of the model are computed on the (D,kBT/J) and (h,kBT/J) planes by taking into account the thermal variations of the order-parameters. The obtained phase diagrams reveal different phase regions with ground state values of 1 and 1/2 in addition to tricritical and critical end points. Simple and double hysteresis loops are also observed in the model.

Phase transition and piezoelectric property of (Ag,K)NbO3 ceramics

AgNbO3 is an antiferroelectric (AFE) material with double hysteresis loop. Both the antiferroelectricity and ferroelectricity can be enhanced by doping. Herein, the ferroelectricity of AgNbO3 ceramics was enhanced via K-doping and the phase diagram of the (Ag1-xKx)NbO3 ceramics was upgraded. In details, (Ag1-xKx)NbO3 ceramics are ferrielectric (FIE) M1 phase as x = 5.00–5.50 mol% and ferroelectric (FE) O phase as x = 5.75–6.00 mol% before poling, and FE O phase as x = 5.00–6.00 mol% after poling at room temperature. With increasing temperature, (Ag1-xKx)NbO3 ceramics show the phase evolutions from FIE M1, AFE M2 to paraelectric (PE) T phase at x = 5.00–5.50 mol% and from FE O, FE T to PE T phase at x = 5.75–6.00 mol% before poling, and from FE O, FE T to PE T phase at x = 5.00–6.00 mol% after poling. High d33 values of 180 pC/N and 285 pC/N are obtained at the FE O-FE T and FE T-PE T phase boundaries. This work sheds light on a novel and promising lead-free piezoelectric system.

Surface charge mediated polar response in ferroelectric nanoparticles

Interfacial phenomena in dielectric-ferroelectric composites have significant potential for promoting novel properties. Here, we utilize a dynamic Landau–Ginzburg–Devonshire methodology to elucidate the influence of an electrostatic self-interaction on the polarization behavior of spherical ferroelectric nanoparticles embedded in a dielectric matrix. By varying the particle volume and the dielectric permittivity of the surrounding medium, phase boundaries between states with polarization patterns exhibiting monodomains, structural, and electrical polydomains, and vortex-like topologies are observed in isolated particles. Under an applied bias, incomplete screening of surface charges leads to a size-dependent, monodomain-to-vortex topological phase transition that suppresses macroscopic polarization. The vortex topology observed in the polarization-suppressed region of the hysteresis originates from the minimization of surface charges at the particle-matrix interface, resulting in linear behavior and double hysteresis loops.

Defect controlling of BaTiO3@ NiO double hysteresis loop ceramics with enhanced energy storage capability and stability

Dielectric capacitor with high energy storage density has become a pivotally enabling technology in electronic industry. The most critical factors affecting energy storage capacity are polarization and breakdown strength. Here the BaTiO3@ NiO double-hysteresis-loop ceramics with different polarization characteristics are prepared by changing the sintering atmosphere to control the defect structure. Results show that, the samples sintered in oxygen exhibit the obviously characteristics of double hysteresis loop, higher polarization and larger breakdown strength. In contrast, the samples sintered in nitrogen have lower polarization and breakdown strength and weaker double hysteresis loop. It is proved that the double hysteresis loop is caused by the defects of the inner layer and the outer layer by regulating the defect structure. Firstly, Low valence Ni ions replace Ti ions to form NiTi''−Vo•• defect dipoles. These charged defect dipoles could be pinned the domain wall, and the existence of oxygen vacancies restricts the movement of the domain wall, making the material appeared a pinched hysteresis loop similar to the double hysteresis loop as observed in antiferroelectrics. Secondly, the local electric field generated by the depletion layer at the interface may also trigger a new polarization features in the material. This double hysteresis loop helps to improve the polarization and energy storage capacity of the material.Finally, the excellent energy storage density of the oxygen samples reaches up to 2.48 J cm−3at 340 kV cm-1 with prominent cycle stability and temperature stability. This work provides a prospective method to fabricate material with high energy storage performance by the adjustment defect structure to control the polarization mechanism in the BaTiO3@1NiO ceramics.

Hf1–xZrxO2/ZrO2 Nanolaminate Thin Films as a High-κ Dielectric

Engineering of HfO2–ZrO2 ferroelectric thin films can substantially increase their dielectric constant. Here, we investigate dielectric and structural properties of ∼10 nm thin films consisting of stacked 1 nm thin ferroelectric (FE) Hf1–xZrxO2 (HZO(x)) and antiferroelectric (AFE) ZrO2 layers. At x < 0.5, the measurements of polarization vs electric field revealed pure FE hysteresis loops, whereas at x > 0.5, pinched hysteresis loops with some remnant polarization were observed, which indicate a coexistence of FE and AFE orderings. Finally, a pure ZrO2 thin film (x = 1) exhibits only an AFE double hysteresis loop. In this way, we demonstrate that the coexistence of FE and AFE orderings can be controlled by adjusting the composition of HZO(x) layers in the HZO(x)/ZrO2 nanolaminate films. At x = 0.5, the dielectric constant is ∼60 in nanolaminate films, which is much higher than that of the conventional HZO(x) solid solution thin films. Structural investigations confirm a coexistence of polar orthorhombic and nonpolar tetragonal structures, which is consistent with the observed polarization hysteresis loops. We also show that the strain generated in the nanolaminate structure significantly facilitates a field-induced transition from the AFE to the FE phase. The design does not considerably affect the leakage current in HZO(x)/ZrO2 nanolaminate films, which makes this system highly promising for complementary metal oxide semiconductor-compatible capacitors.