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1.
I. P. Pronin E. Yu. Kaptelov E. A. Tarakanov T. A. Shaplygina V. P. Afanas’ev A. V. Pankrashkin 《Physics of the Solid State》2002,44(4):769-773
This paper reports on a study of the electrical properties of 0.7–1-μm-thick textured PZT ferroelectric films prepared by
rf magnetron sputtering of a PbZr0.54Ti0.46O3 target which additionally contained 10 mol % lead oxide. Such films are shown to feature a combination of a self-polarized
state and migratory polarization. The totality of the data obtained suggest that the films had n-type conduction. As shown by the laser beam modulation technique, the polarization was distributed nonuniformly in depth,
with most of the poled state localized near the lower interface of the thin-film ferroelectric capacitor. The mechanism underlying
the onset of this self-polarization is related to the charging of the lower interface of the structure by electrons, which
occurs during the cooling following the high-temperature treatment of the PZT film, and to poling of the bulk of the film
by the charged interface. This mechanism of the self-polarization of ferroelectric films is believed to have a universal character.
__________
Translated from Fizika Tverdogo Tela, Vol. 44, No. 4, 2002, pp. 739–744.
Original Russian Text Copyright ? 2002 by Pronin, Kaptelov, Tarakanov, Shaplygina, Afanas’ev, Pankrashkin. 相似文献
2.
The effects of TiOx diffusion barrier layer thickness on the microstructure and pyroelectric characteristics of PZT thick films were studied in this paper. The TiOx layer was prepared by thermal oxidation of Ti thin film in air and the PZT thick films were fabricated by electrophoresis deposition method (EPD). To demonstrate the barrier effect of TiOx layer, the electrode/substrate interface and Si content in PZT thick films were characterized by scanning electron microscope (SEM) and X-ray energy dispersive spectroscopy (EDS), respectively. The TiOx barrier thickness shows significant influence on the bottom electrode and the pyroelectric performance of the PZT thick films. The average pyroelectric coefficient of PZT films deposited on 400 nm TiOx layer was about 8.94 × 10−9 C/(cm2 K), which was improved by 70% than those without diffusion barrier layer. The results showed in this study indicate that TiOx barrier layer has great potential in fabrication of PZT pyroelectric device. 相似文献
3.
S. Muensit P. Sukwisut P. Khaenamkeaw S. B. Lang 《Applied Physics A: Materials Science & Processing》2008,92(3):659-663
Sol–gel techniques were used to prepare thin films of Pb(Zr
x
,Ti1−x
)O3 (PZT) with three different Zr/Ti ratios and a graded PZT film with three different compositional layers. A Michelson interferometer
was used to measure the thickness strains due to an applied ac electric field. Effective d
33 piezoelectric strain coefficients were computed from the experimental data. Interfacial pinning caused these coefficients
to differ from the true ones. They were corrected for the pinning using both an analytical model and finite-element analysis.
The corrected coefficients of the PZT (52/48) sample were in excellent agreement with values of bulk materials. The coefficients
of the multilayer sample were very low, probably due to insufficient poling or domain switching. 相似文献
4.
《Current Applied Physics》2002,2(5):407-409
Ferroelectric thin films of sol–gel-derived Pb(Zrx, Ti1−x)O3 (lead–zirconate–titanate, PZT) were obtained by the low-temperature processing employing oxygen-plasma treatment. The as-coated PZT films were annealed in oxygen ambience at 450 °C, followed by oxygen-plasma treatment at 200 °C, which gave rise to the ferroelectric hysteresis. Annealing of the as-coated PZT films followed by oxygen-plasma teratment at 200 °C gave rise to the ferroelectric hysteresis. 相似文献
5.
The preparation process, crystallinity and electrical properties of pulse laser deposited Pb(ZrxTi1−x)O3 (PZT) thin films were investigated in this paper. PZT (x = 0.93) thin film samples deposited at different substrate temperatures were prepared. Si (1 1 0) was the substrate; Ag and YBCO were the top electrode and the bottom electrode respectively. The bottom electrode YBCO was deposited on the Si substrate by pulsed laser deposition (PLD), and then PZT was epitaxially deposited on YBCO also by PLD. After annealing, the top electrode Ag was prepared on PZT by thermal evaporation, and then the Ag/PZT/YBCO/Si structured thin films were obtained. The XRD and the analysis of their electrical characters showed that, when the substrate temperature was elevated from 600 °C to 800 °C, the crystallinity and electrical properties of PZT thin films became better and better, and the FR(LT)–FR(HT) phase transition of PZT (x = 0.93) thin films occurred at 62 °C. The PZT film deposited at 800 °C had the best pyroelectric properties, and when the FR(LT)–FR(HT) phase transition of this film occurred, the peak value of pyroelectric coefficient (p) was obtained, with a value of 1.96 × 10−6 C/(cm2 K). The PZT film deposited at 800 °C had the highest remnant polarization (Pr) and the lowest coercive field (Ec), with the values of 34.3 μC/cm2 and 41.7 kV/cm respectively. 相似文献
6.
C.?Kügeler U.?B?ttger T.?Schneller 《Applied Physics A: Materials Science & Processing》2009,94(4):739-745
This paper focuses on the deposition and electromechanical characterization of lanthanum-doped lead hafnate titanate (PLHT)
thin films as key material in piezoelectric microelectromechanical systems (pMEMS). PLHT (x/30/70) and PLHT(x/45/55) films with a thickness between 150 nm and 250 nm were deposited by chemical solution deposition (CSD). Thereby x varies between 0 and 10% La content. The electrical characterization shows that undoped (x=0) PLHT exhibit ferroelectric behavior similar to PZT of the same composition. La doping results in reduced ferroelectric
properties and also affects the electromechanical properties. Measurements using a double beam laser interferometer yield
a piezoelectric coefficient d
33 of 60 pm/V, which stays constant with an increasing electric field. This leads to a linear displacement compared to undoped
PLHT or conventional PZT films used for MEMS applications. 相似文献
7.
8.
Dong Hua Li 《Applied Surface Science》2006,252(13):4541-4544
In order to study the effect of different buffer layers on the Pb(Zr0.52Ti0.48)O3 (PZT) thin films, 10-nm thick (Pb0.72La0.28)Ti0.93O3 (PLT) and Pb(Zr0.52Ti0.48)O3 buffer layers have been deposited on the Pt(1 1 1)/Ti/SiO2/Si substrates by pulsed laser deposition, respectively. The top buffer layers were also deposited on PZT thin films with the same thickness of the seed layers in order to enhance the fatigue characteristics of PZT thin films. We compared the results of dielectric constant, hysteresis loops and fatigue resistance characteristics. It was found that the dielectric properties of PZT thin films with PLT buffer layers were improved by comparing with PZT thin films with PZT buffer layers. The polarization characteristics of PZT thin films with PLT buffer layers were observed to be superior to those of PZT thin films using PZT buffer layers. The remanent polarization of PZT thin films showed 36.3 μC/cm2 and 2.6 μC/cm2 each in the case of use PLT and PZT buffer layers. For the switching polarization endurance analysis, PZT thin films with PLT buffer layers showed more excellent result than that of PZT thin films with PZT buffer layers. 相似文献
9.
Polymer/lead zirconate titanate {[Pb(Zrx, Ti1-x)O3], PZT, x = 0.40} flexible composite films are prepared by solvent evaporation technique. Carbon tape used as a top and bottom electrodes for fabricating flexible PZT composite films. The phase purity and functional groups of PZT and polymer humps are confirmed by XRD and FTIR respectively. XPS analysis showed that PMMA contains carbon (C) and oxygen (O). Carbon (C), oxygen (O), lead (Pb), zirconium (Zr) and titanium (Ti) are present in PZT/PMMA composite films. The chemical states of Pb, Zr and Ti ions are 2+, 4+ and 4+ respectively confirmed by XPS. The higher forefinger bending motion of the film is found to reveal greater output voltage (5.2 V) than the output voltage (1.6 V) for slight bending motion of the forefinger. Therefore, based on the results human mechanical forces induce compressive stress on PZTs ferroelectric based composite films and are excellent candidate for energy harvester. 相似文献
10.
《Current Applied Physics》2019,19(7):804-810
Multi-layered structures, composed of thin films from materials with different compositions or physical properties, represents a way to obtain enhanced properties or even new functionalities. In this work, lead zirconate titanate PbZrxTi1-xO3 (PZT; x = 0.20, 0.52, 0.80) multilayers were grown by pulsed laser deposition (PLD) on a single crystal strontium titanate (SrTiO3, STO) substrate, using a strontium ruthenate (SrRuO3, SRO) film as buffer layer for epitaxial growth, and also as back electrode.Up and down multi-layers were grown and their physical and structural properties were compared, up being the structure in which Zr concentration was varied from 20% near the STO substrate to 80% at the surface, while down is for the structure in which the Zr concentration starts with 80% near the substrate and ends with 20% at the surface. It was found that the electric and pyroelectric properties of the two graded structures are significantly different. The up structure presents electric properties that are comparable with those of single composition PZT films while the properties of the down structure are deteriorated, especially in terms of the leakage current magnitude. Pyroelectric signal could be measured only for the up structure. These differences were attributed to larger density of structural defects in the down structure compared to the up one. This is due to the different growth sequence: up structure starts with tetragonal PZT on cubic substrate (lower lattice mismatch, 1.1%) while down structure starts with rhombohedral PZT on cubic substrate (larger lattice mismatch, almost 5%). 相似文献
11.
12.
S. Firmino?Mendes C. M. Costa V. Sencadas J. Serrado?Nunes P. Costa R. Gregorio J. L. Gomez Ribelles S. Lanceros-Méndez 《Applied Physics A: Materials Science & Processing》2009,96(4):1037-908
In this work, poly(vinilidene fluoride)/Pb(Zr0.53Ti0.47)O3([PVDF]1−x
/[PZT]
x
) composites of volumetric fractions x and (0–3) type connectivity were prepared in the form of thin films. PZT powder of crystallite size of 0.84, 1.68, and 2.35
μm in different amounts of PZT (10, 20, 30, and 40%) was mixed with the polymeric matrix. The crystalline phase of the polymeric
matrix was the nonpolar α-phase and the polar β-phase.
Dielectric and dynamic mechanical (DMA) measurements were performed to these composites in order to evaluate the influence
of particle size and the amount of PZT filler with respect to the PVDF matrix. The inclusion of ceramic particles in the PVDF
polymer matrix increases the complex dielectric constant and dynamical mechanical response of the composites. A similar behavior
is observed for the α- or β-phase of the polymeric matrix indicating that the PVDF polymer matrix is not particularly relevant for the composite behavior.
On the other hand, ceramic size and especially content play the major role in the increase of the dielectric response and
the room temperature storage modulus. In particular, the storage modulus increases with increasing PZT concentration, but
this increase is more pronounced, in terms of maximum value, for the sample with 2.35 μm particle size; DMA reveals two main
relaxations in the analyzed samples. A low-temperature process maximum at ca. −40°C, usually labeled by β or α
a
associated to the T
g
of the polymer and the α-relaxation at temperatures above 30°C. The β-relaxation is also observed in the dielectric measurements.
The models used to asses the dielectric behavior of the samples with increasing PZT concentration indicate that the particle–matrix
interaction plays a relevant role, as well as the particle asymmetry and relative orientation, being the Yamada model the
most appropriate to describe the composite behavior.
An erratum to this article can be found at 相似文献
13.
Yu. P. Sukhorukov N. N. Loshkareva E. A. Gan’shina E. V. Mostovshchikova I. K. Rodin A. R. Kaul O. Yu. Gorbenko A. A. Bosak A. S. Moskvin E. V. Zenkov 《Journal of Experimental and Theoretical Physics》2003,96(2):257-267
The variations in the electronic structure and the evolution of phase separation as a result of creation of vacancies or excess of lanthanum in lanthanum manganites are studied on the basis of analysis of optical and magnetic properties of LaxMnO3 epitaxial films (0.83≤x≤1.10) in the fundamental absorption range. The Kerr effect, the temperature dependences of resistivity, optical density, and magnetoabsorption of light indicate the charge and magnetic phase separation in the films. The fine structure observed in the spectrum is attributed to spectral overlapping of electron transitions with charge transfer and geometrical resonances reflecting an inhomogeneous nanoscopic structure of the films, which strongly depends on stoichiometry and stresses emerging during film deposition. It is shown that, in contrast to bulk polycrystals, the gradient of stresses over the film thickness significantly affects the phase separation in the films. 相似文献
14.
T. Wei Y. Wang C. Zhu X.W. Dong Y.D. Xia J.S. Zhu J.-M. Liu 《Applied Physics A: Materials Science & Processing》2008,90(1):185-189
The ferroelectric and polarization fatigue characteristics of Pb1-xCax(Zr0.52Ti0.48)O3 (PCZT) thin films prepared using the sol–gel method were studied. The Ca-doping slightly suppresses the ferroelectricity
of Pb(Zr0.52Ti0.48)O3 (PZT) because of the quantum paraelectric behavior of CaTiO3. Compared with PZT thin films, the PCZT (x=0.2) thin films show enhanced fatigue resistance at room temperature, further
emphasized by the almost fatigue-free behavior at 100 K. The temperature-dependent dc-conductivity suggests a decrease of
the oxygen vacancy density by almost 20 times and a slightly declined activation energy U for oxygen vacancies, upon increasing
of the Ca-doping content from 0.0 to 0.2. It is argued that the improved fatigue endurance is ascribed to the decreasing density
of oxygen vacancies due to the Ca-doping, although the lowered activation energy of oxygen vacancies is unfavorable.
PACS 77.84.Dy; 66.30.-h; 68.35.Fx 相似文献
15.
Pb(Zr0.52Ti0.48)O3 (PZT) thin films with large remanent polarization and SrBi2Ta2O9 (SBT) thin films with excellent fatigue-resisting characteristic have been widely studied for non-volatile random access memories, respectively. To combine these two advantages, bilayered Pb(Zr0.52Ti0.48)O3/SrBi2Ta2O9 (PZT/SBT) thin films were fabricated on Pt/TiO2/SiO2/Si substrates by chemical solution deposition method. X-ray diffraction patterns revealed that the diffraction peaks of PZT/SBT thin films were completely composed of PZT and SBT, and no other secondary phase was observed. The electrical properties of the bilayered structure PZT/SBT films have been investigated in comparison with pure PZT and SBT films. PZT/SBT bilayered thin films showed larger remanent polarization (2Pr) of 18.37 μC/cm2 than pure SBT and less polarization fatigue up to 1 × 109 switching cycles than pure PZT. These results indicated that this bilayered structure of PZT/SBT is a promising material combination for ferroelectric memory applications. 相似文献
16.
M. Khodaei S. A. Seyyed Ebrahimi Yong Jun Park Jong Mok Ok Jun Sung Kim Junwoo Son Sunggi Baik 《Applied Physics A: Materials Science & Processing》2014,117(3):1153-1160
The CoFe2O4 and Co0.8Fe2.2O4 single layer (CFO) as well as PZT/CoFe2O4 and PZT/Co0.8Fe2.2O4 bilayer thin films were grown using the pulsed laser deposition technique on Pt(111)/Si substrates at 600 °C. All films had a perfect (111)-orientation and the degree of orientation of CFO films was improved by the deposition of a PZT top layer. Precision X-ray diffraction analysis (avoiding the shift of peaks due to sample misalignment) revealed that the CFO films on Pt(111)/Si substrate were under an out-of-plane contraction and the deposition of a PZT top layer led to the increase in the out-of-plane contraction. The (111)-oriented CFO single layer films had a strong in-plane magnetic anisotropy as a result of orientation as well as the stress-induced magnetic anisotropy. The magnetic properties of CFO film were altered by the deposition of a PZT top layer leading to the enhancement of in-plane magnetic anisotropy. The enhanced in-plane magnetic anisotropy was more detectable in PZT/Co0.8Fe2.2O4 rather than PZT/CoFe2O4 bilayer film, which could be expected from its higher magnetocrystalline as well as magnetostriction constants. 相似文献
17.
Lijun Jia Tao Li Huaiwu Zhang Hui Zhong Yingli Liu Gang Xue 《Journal of magnetism and magnetic materials》2009,321(18):2936-2940
To adjust the dielectric constant and the initial permeability of NiCuZn-ferrite materials for suppressing electromagnetic interference, Pb0.95Sr0.05(Zr0.52Ti0.48)O3 (PZT) was introduced. The effects of PZT additive on the phase composition, densification, microstructures and electromagnetic properties of the ceramics with composition of xPZT+(1−x)NiCuZn-ferrite (where x=0-25 wt%) were investigated. The results show that these composites are mainly of spinel phase, exhibiting relatively high dielectric constant and initial permeability due to the mutual effects of magnetization of NiCuZn-ferrite phase and polarization of PZT phase. Meanwhile, relatively high-quality factor (Q) and excellent frequency stability were obtained for the samples with PZT additive. These materials are expected to be used as embedded inductors or embedded capacitors. 相似文献
18.
0.95 Ti0.05)O3 (PZT 95/5) thin films of perovskite structure were prepared on various substrates by the radio-frequency magnetron sputtering
with a stoichiometric ceramic target. The crystal structure of the films showed a strong dependency on the crystal structure
of the substrates. After conventional-furnace annealing at 750 °C, crack-free and transparent epitaxial PZT 95/5 films were
successfully obtained on SrTiO3(100) substrates, and highly oriented films on LaAlO3(012). The films on r-sapphire exhibit slightly preferred orientation along both the (040) and (122) axes of the orthorhombic
PZT 95/5 phase. The films on YSZ(100) consist principally of the perovskite PZT 95/5 phase with random orientation with a small
portion of unknown phase. However, the formation of the perovskite PZT 95/5 phase was not observed in the films on Si(110)
or (111)Pt-coated Si substrates. The crystallization of the perovskite PZT 95/5 on these substrates could be improved by rapid
thermal annealing (RTA). Single perovskite phase was obtained in the films on (111)Pt/Si which had RTA at 750 °C for 1 min.
No tangible loss of Pb from the films occurred during either the sputtering or annealing.
Received: 17 April 1997/Accepted: 18 November 1997 相似文献
19.
M. P. Ivliev 《Bulletin of the Russian Academy of Sciences: Physics》2010,74(9):1203-1205
A phase diagram identical to the x-T diagram for lead zirconate-titanate (PZT) solid solutions (PbZr1 − x
Ti
x
O3) was obtained on the basis of a statistical 12-minima model in the vicinity of the cubic phase boundary. The applicability
of this model to the phase transitions in PZT is discussed. 相似文献
20.
S. A. Gridnev A. G. Gorshkov A. V. Sitnikov 《Bulletin of the Russian Academy of Sciences: Physics》2007,71(10):1408-1410
Conductivity of thin-film heterogeneous Cox(PZT)1 ? x structures has been studied in a wide ranges of metallic phase concentrations and temperatures. The crystallization kinetics of amorphous samples of Cox(PZT)100 ? x nanocomposites has been investigated by analyzing the time dependences of their conductivity. The main parameters of the crystallization process have been determined. 相似文献