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15 Oct 2003

Volume 94, Issue 8, pp. 4743-5438

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Dielectric relaxation in laser ablated polycrystalline ZrTiO4 thin films

P. Victor, S. Bhattacharyya, and S. B. Krupanidhi

J. Appl. Phys. 94, 5135 (2003); http://dx.doi.org/10.1063/1.1606509 (8 pages) | Cited 17 times

Online Publication Date: 30 September 2003

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Relaxation and conduction mechanisms under small ac fields of laser ablated ZrTiO4 thin films were analyzed in the light of impedance and modulus spectroscopy. The overall dielectric properties were mainly dominated by a Maxwell–Wagner type of relaxation with grains and the grain boundary two distinct parts of the circuit. Each of these parts was found to follow the universal power law of frequency dispersion. The modulus plot confirmed that the capacitive parts were relatively independent of the frequency and temperature, whereas the impedance and ac conduction studies exhibited significant temperature and frequency dependence. The conduction inside the grains was suggestive of a hopping mechanism through various defect sites whereas the interface barrier potential dictated grain boundary conduction. © 2003 American Institute of Physics.
Show PACS
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
77.55.-g Dielectric thin films
77.22.Gm Dielectric loss and relaxation
61.72.Mm Grain and twin boundaries
73.50.Dn Low-field transport and mobility; piezoresistance
61.80.Ba Ultraviolet, visible, and infrared radiation effects (including laser radiation)
73.61.Ng Insulators

Properties and lanthanum distribution of Bi4−xLaxTi3O12−SrBi4−yLayTi4O15 intergrowth ferroelectrics

Jun Zhu, Rong Hui, Xiang Yu Mao, Wang Ping Lu, Xiao Bing Chen, and Zeng-Ping Zhang

J. Appl. Phys. 94, 5143 (2003); http://dx.doi.org/10.1063/1.1604960 (4 pages) | Cited 12 times

Online Publication Date: 30 September 2003

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Using the standard solid-state reaction method, several lanthanum-doped intergrowth ferroelectric ceramics of type Bi4−xLaxTi3O12−SrBi4−yLayTi4O15 [BLT–SBLT (x+y)] were synthesized with the lanthanum doping content, (x+y), ranging from 0.00 to 1.50. The remnant polarization (2Pr) of the samples, which varies with (x+y), has a maximum when x+y=0.50, that is nearly 60% greater than at zero doping. The Curie temperature Tc decreases monotonously with (x+y). By assumpting that the Curie temperature of BLT-SBLT (x+y) is the average of Tcs for its two constituents BLT and SBLT, La distribution in each constituent is estimated. The result demonstrates that when (x+y) is small (⩽1.25), La concentration in BLT constituent is higher than that in SBLT; but when x+y=1.50, more La3+ ions would prefer substituting the Bi3+ ions in SBTi. This finding agrees well with the behavior of d(118) lattice space as well as the relaxation characteristics observed in BLT–SBLT(1.50). © 2003 American Institute of Physics.
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77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
77.80.B- Phase transitions and Curie point
77.22.Ej Polarization and depolarization
81.05.Je Ceramics and refractories (including borides, carbides, hydrides, nitrides, oxides, and silicides)
77.80.Dj Domain structure; hysteresis

Nonlinear electric field dependence of piezoresponse in epitaxial ferroelectric lead zirconate titanate thin films

Lang Chen, V. Nagarajan, R. Ramesh, and A. L. Roytburd

J. Appl. Phys. 94, 5147 (2003); http://dx.doi.org/10.1063/1.1610242 (6 pages) | Cited 39 times

Online Publication Date: 30 September 2003

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Landau–Devonshire-type phenomenological thermodynamic theory is employed to explain the electric field dependence of piezoelectric properties of tetragonal single domain PbZrxTi1−xO3 (PZT). The strong nonlinearity of the converse piezoelectric coefficient under a large external electric field is proved to be intrinsic both in bulk crystal and epitaxial tetragonal PZT thin films. The tunability of piezoelectric responses by an external electric field and its dependence on the film/substrate misfit and elastic compliance of thin films are characterized quantitatively. The theoretical predictions are in good agreement with the experimental results of piezoresponse scanning microscopy. Due to the large tunability of piezoresponse in it, PZT 50/50 (x=0.5) epitaxial film is a promising candidate for use in future tunable devices. © 2003 American Institute of Physics.
Show PACS
77.55.-g Dielectric thin films
77.65.Bn Piezoelectric and electrostrictive constants
77.80.-e Ferroelectricity and antiferroelectricity
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates

Structural and dielectric properties of Ga-modified BiFeO3–PbTiO3 crystalline solutions

Jin-Rong Cheng, Nan Li, and L. Eric Cross

J. Appl. Phys. 94, 5153 (2003); http://dx.doi.org/10.1063/1.1609655 (5 pages) | Cited 53 times

Online Publication Date: 30 September 2003

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The dielectric and structural properties of Bi(GaxFe1−x)O3–PbTiO3 (BGF–PT) crystalline solutions have been investigated. Studies have focused on phase-pure perovskite materials. With increasing Ga content, we have found: (i) a coexistence of tetragonal and rhombohedral ferroelectric phases; (ii) a multicell perovskite structure for BGF–0.3PT; and (iii) a maximum tetragonal c/a ratio for the composition BGF–0.6PT with x=0.25. Also, Ga modification increases the electrical resistivity to ⩾1012 Ω cm, reduces the dielectric loss or tan δ over a wide temperature range, and increases the dielectric constant K. We have developed BGF–PT materials with values of K>400 and of tan δ<0.03. © 2003 American Institute of Physics.
Show PACS
77.22.Ch Permittivity (dielectric function)
77.80.-e Ferroelectricity and antiferroelectricity
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
61.66.Fn Inorganic compounds
77.22.Gm Dielectric loss and relaxation
72.80.Sk Insulators

Electron beam generation in a diode with different ferroelectric cathodes

Ya. E. Krasik, K. Chirko, A. Sayapin, J. Gleizer, A. Krokhmal, and J. Felsteiner

J. Appl. Phys. 94, 5158 (2003); http://dx.doi.org/10.1063/1.1611628 (5 pages) | Cited 5 times

Online Publication Date: 30 September 2003

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We present experimental results of electron beam generation in a diode with cathodes made of BaTi solid solution and prepoled and unpoled PZT ferroelectrics without a screening grid in front of them. The diode operates with an accelerating pulse of ∼200 kV and ∼300 ns duration. It was found that although a surface plasma is always formed as a result of the application of a driving pulse, the beginning of the electron emission does not always coincide with the start of the accelerating pulse. Namely, it was shown that the application of the accelerating pulse at the same time with the driving pulse leads to simultaneous electron emission from the surface plasma only in the case of coincidence of the driving and accelerating electric field directions. In the opposite case, electron emission starts only at the end or at the fall of the driving pulse for the BaTi and PZT samples, respectively. Also, it was found that the electron beam current density distribution corresponds to the plasma emission spots which appear at the ferroelectric surface. © 2003 American Institute of Physics.
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77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
79.70.+q Field emission, ionization, evaporation, and desorption
84.47.+w Vacuum tubes
85.50.-n Dielectric, ferroelectric, and piezoelectric devices

Leakage current and relaxation characteristics of highly (111)-oriented lead calcium titanate thin films

X. G. Tang, J. Wang, Y. W. Zhang, and H. L. W. Chan

J. Appl. Phys. 94, 5163 (2003); http://dx.doi.org/10.1063/1.1611627 (4 pages) | Cited 11 times

Online Publication Date: 30 September 2003

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Highly (111)-oriented (Pb0.76Ca0.24)TiO3 (PCT) thin films were grown on Pt/Ti/SiO2/Si substrates by a sol–gel process. The Au/PCT/Pt metal–insulator–metal film capacitor showed well-saturated hysteresis loops at an applied field of 800 kV/cm with remanent polarization (Pr) and coercive electric field (Ec) values of 18.2 μC/cm2 and 210 kV/cm, respectively. The leakage current depended on the voltage polarity. At low electrical field and with Pt electrode biased negatively, the Pt/PCT interface exhibits a Schottky emission characteristics. The Au/PCT interface forms an ohmic contact. The conduction current when the Au electrode is biased negatively shows a space-charge-limited behavior. The dielectric relaxation current behavior of Au/PCT/Pt capacitor obeys the well-known Curie–von Schweidler law at low electric field. At higher fields, the currents have contributions to both dielectric relaxation current and leakage current. © 2003 American Institute of Physics.
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77.55.-g Dielectric thin films
68.55.-a Thin film structure and morphology
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
73.40.Rw Metal-insulator-metal structures
73.30.+y Surface double layers, Schottky barriers, and work functions

Crystallographic and optical properties of epitaxial Pb(Zr0.6,Ti0.4)O3 thin films grown on LaAlO3 substrates

B. Vilquin, R. Bouregba, G. Poullain, H. Murray, E. Dogheche, and D. Remiens

J. Appl. Phys. 94, 5167 (2003); http://dx.doi.org/10.1063/1.1610776 (5 pages) | Cited 5 times

Online Publication Date: 30 September 2003

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Pb(Zr0.6,Ti0.4)O3 (PZT) thin films are grown in situ on LaAlO3 substrates by rf magnetron sputtering. The relationship between structural and optical properties is investigated as a function of growth temperature. The ferroelectric films exhibit satisfying crystallization with epitaxial growth from 475 °C. The optical refractive index value is 2.558, in agreement with the bulk value. The films show homogeneous structure and the squarelike shape of the index profile along with the PZT thickness suggests a good interface quality with the substrate. The crystallographic and optical properties measured on our films tend to demonstrate the suitability of in situ grown PZT films for optical applications. © 2003 American Institute of Physics.
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77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
77.55.-g Dielectric thin films
68.55.-a Thin film structure and morphology
78.66.Nk Insulators
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)
42.70.Nq Other nonlinear optical materials; photorefractive and semiconductor materials

Model of the polarization response of single-crystal lead magnesium niobate-lead titanate for transducer applications

Jean C. Piquette, Ahmed H. Amin, and Elizabeth A. McLaughlin

J. Appl. Phys. 94, 5172 (2003); http://dx.doi.org/10.1063/1.1610808 (10 pages) | Cited 1 time

Online Publication Date: 30 September 2003

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A theoretical model is developed and applied to experimentally measured polarization acquired from lead magnesium niobate lead titanite (PMN–PT) single crystals. The model is shown to describe well the polarization behavior with respect to changes in temperature and applied electric field at a variety of levels of applied prestress. Including the effects of prestress is important if the model is to be used in transducer design and output control. Large prestresses are applied to the active materials used in transducers in order to prevent the driver from extending. (Damage to the driver is much more likely should it go into extension during operation, and large applied prestress reduces this possibility.) Physically, the model accounts for both rotation and stretching of elementary dipoles, and realistic values for the elementary dipole moment and dipole concentration are deduced from the measurements using the model. Reasonable dipole behavior with respect to changes in temperature, stress, and electric field is also seen. The model has been shown to successfully interpolate and extrapolate measurements in temperature and electric field at various levels of applied prestress, thus allowing a significant reduction in the number of measurements that must be acquired to characterize single-crystal PMN–PT for transducer applications.
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77.22.Ej Polarization and depolarization
85.50.-n Dielectric, ferroelectric, and piezoelectric devices
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates

Frequency and temperature dependent dielectric and conductivity behavior of KNbO3 ceramics

B. Sundarakannan, K. Kakimoto, and H. Ohsato

J. Appl. Phys. 94, 5182 (2003); http://dx.doi.org/10.1063/1.1610260 (6 pages) | Cited 31 times

Online Publication Date: 30 September 2003

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Dielectric and conductivity measurements were carried out on the potassium niobate ceramics both as a function of temperature (50 to 550 °C) and frequency (102 to 106 Hz). A low-frequency dielectric relaxation in the temperature range of 100 to 200 °C is observed and analyzed with the Cole–Cole function. The activation energy of dielectric relaxation is estimated to be 0.84 eV. Frequency dependent conductivity data are analyzed with an augmented Jonscher relation. Potassium niobate exhibits universal conductivity behavior. Activation energies obtained for the dc conductivity and the hopping frequency are 1.01 and 0.94 eV, respectively. A possible mechanism for both the low-frequency dielectric relaxation and the frequency dependent conductivity is proposed based on activation energies and off stoichiometry of KNbO3, which is resulted due to potassium oxide evaporation during preparation processes. © 2003 American Institute of Physics.
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77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
72.20.Fr Low-field transport and mobility; piezoresistance
72.80.Sk Insulators
77.22.Gm Dielectric loss and relaxation
72.20.Ee Mobility edges; hopping transport

Effects of La substituent on ferroelectric rhombohedral/tetragonal morphotropic phase boundary in (1−x)(Bi,La)(Ga0.05Fe0.95)O3–xPbTiO3 piezoelectric ceramics

Jin-Rong Cheng and L. Eric Cross

J. Appl. Phys. 94, 5188 (2003); http://dx.doi.org/10.1063/1.1610802 (5 pages) | Cited 41 times

Online Publication Date: 30 September 2003

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Crystalline solutions of (1−x)(Bi,La)(Fe0.95Ga0.05)O3–xPbTiO3 (BLGF–PT) have been fabricated with La concentrations of 0, 10, and 20 at. %. The BLGF–PT system has been found to have excellent insulation resistivity ⩽1013 Ω cm. In addition, La substituent was found to decrease the coercive field, resulting in much improved dielectric and piezoelectric properties. A shift in the morphotropic phase boundary of BLGF–PT with increasing La content was identified for x=0.3, 0.4, and 0.43. We have achieved optimized dielectric constant, loss factor, Curie temperature, remnant polarization, and piezoelectric d33 properties of 881, 0.037, 386 °C, 30 μC/cm2 and 163 pC/N, respectively, for 0.6BLGF–0.4PT with 10 at. % La. These results clearly demonstrate that BLGF–PT is a competitive alternative piezoelectric material to Pb(Zr,Ti)O3 with reduced lead content. © 2003 American Institute of Physics.
Show PACS
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
77.65.Bn Piezoelectric and electrostrictive constants
77.80.B- Phase transitions and Curie point
77.22.Ej Polarization and depolarization
72.20.Fr Low-field transport and mobility; piezoresistance
72.80.Sk Insulators
77.22.Ch Permittivity (dielectric function)
77.22.Gm Dielectric loss and relaxation

Defects in CeO2/SrTiO3 fabricated by automatic feeding epitaxy probed using positron annihilation

A. Uedono, K. Shimoyama, M. Kiyohara, and K. Yamabe

J. Appl. Phys. 94, 5193 (2003); http://dx.doi.org/10.1063/1.1606112 (6 pages) | Cited 4 times

Online Publication Date: 30 September 2003

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Vacancy-type defects in the CeO2/SrTiO3 structure were studied by means of positron annihilation. Thin CeO2 films were grown on SrTiO3 substrates by molecular-beam epitaxy without using an oxidant; oxygen was supplied by diffusion from the substrate (this process is referred to as automatic feeding epitaxy). A preferential epitaxial growth of CeO2(001) on SrTiO3(001) was observed, but an increase in the film thickness or annealing in an O2 atmosphere caused a partial growth of CeO2(110). The introduction of this phase was found to correlate with the reduction in the concentration of vacancy-type defects. The species of defects introduced into the SrTiO3 substrate was found to be not only oxygen vacancies but also Sr vacancies or their complexes. We discuss the mechanism that introduced cation vacancies in terms of oxygen nonstoichiometry. We found the trapping rate of positrons by Sr vacancies to depend on the sample temperature. This was associated with the temperature dependence of the dielectric constant near the defects or the presence of shallow trapping centers. © 2003 American Institute of Physics.
Show PACS
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
78.70.Bj Positron annihilation
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
61.72.J- Point defects and defect clusters
68.55.Nq Composition and phase identification
61.72.Cc Kinetics of defect formation and annealing
77.22.Ch Permittivity (dielectric function)
77.55.-g Dielectric thin films
77.84.Bw Elements, oxides, nitrides, borides, carbides, chalcogenides, etc.

Electric field induced piezoelectric resonance in the micrometer to millimeter waveband in a thin film SrTiO3 capacitor

Kentaro Morito, Yoshiki Iwazaki, Toshimasa Suzuki, and Masayuki Fujimoto

J. Appl. Phys. 94, 5199 (2003); http://dx.doi.org/10.1063/1.1611268 (7 pages) | Cited 10 times

Online Publication Date: 30 September 2003

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Thin film SrTiO3 metal–insulator–metal (MIM) capacitors were fabricated in order to characterize the piezoelectric resonance in the micrometer to millimeter waveband arising from electric field induced ferroelectricity in the SrTiO3 film. The specimens showed a second-order phase transition, and the piezoelectric resonance appeared when an electric field of 250 kV/cm was applied at room temperature. Finite element method (FEM) analysis was used to interpret the piezoelectric resonance observed in the capacitors. The FEM analysis data basically agrees well with the experimental data, and the few differences between the theoretical and experimental data are interpreted mainly as artifacts caused by overlapping of resonant/antiresonant peaks during the measurement. The piezoelectric resonance of thin film MIM capacitors is strongly influenced by the longitudinal stacked structure of the MIM. © 2003 American Institute of Physics.
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73.40.Rw Metal-insulator-metal structures
85.50.-n Dielectric, ferroelectric, and piezoelectric devices
84.32.Tt Capacitors
77.65.Fs Electromechanical resonance; quartz resonators
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates

Optomechanical effect in ferroelectric liquid crystal freely suspended films

Serguei V. Yablonskii, Kazuyuki Nakano, Masanori Ozaki, Mikhail V. Kozlovsky, and Katsumi Yoshino

J. Appl. Phys. 94, 5206 (2003); http://dx.doi.org/10.1063/1.1611637 (4 pages) | Cited 1 time

Online Publication Date: 30 September 2003

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Optomechanical effect in vibrating ferroelectric liquid crystal freely suspended films have been observed. In the experiment the liquid crystal films are doped with a photochromic dye which undergoes trans-cis isomerization. Photoisomerization induces the change both in a switching potential of the host liquid crystal and the film surface tension. We observed also a nonlinear dependence of photoinduced variation of the surface tension as function of the dye concentration. Such dependence strongly supports the possibility of amplification of photochemical effect in liquid crystals. The optomechanical effect might be exploited for the remote control of the sensors using freely suspended films, and more generally for the investigation of the cooperative phenomena in liquid crystals. © 2003 American Institute of Physics.
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78.66.Qn Polymers; organic compounds
78.20.hb Piezo-optical, elasto-optical, acousto-optical, and photoelastic effects
77.84.Nh Liquids, emulsions, and suspensions; liquid crystals
42.70.Df Liquid crystals

Origin and implications of the observed rhombohedral phase in nominally tetragonal Pb(Zr0.35Ti0.65)O3 thin films

Maxim B. Kelman, Paul C. McIntyre, Alexei Gruverman, Bryan C. Hendrix, Steven M. Bilodeau, and Jeffrey F. Roeder

J. Appl. Phys. 94, 5210 (2003); http://dx.doi.org/10.1063/1.1610773 (10 pages) | Cited 7 times

Online Publication Date: 30 September 2003

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The structural and electrical properties of Pb(Zr0.35Ti0.65)O3 (PZT) thin films ranging in thickness from 700 to 4000 Å have been investigated. These (001)/(100)-textured films were grown by metalorganic chemical vapor deposition on (111)-textured Ir bottom electrodes. It was observed that, in the as-deposited state, the thinnest PZT films are rhombohedral even though bulk PZT of this composition should be tetragonal. Thicker films have a layered structure with tetragonal PZT at the surface and rhombohedral PZT at the bottom electrode interface. In this article we investigate the origin of this structure and its effect of the ferroelectric and dielectric properties of PZT capacitors. It has been suggested that thin films stresses can affect the phase stability regions of single domain PZT. This possibility has been investigated by piezoresponse microscopy and thin film stress measurements. In the as-deposited state the majority of PZT grains contain a single ferroelastic domain, whereas after a high temperature anneal, a large fraction of the grains contain several ferroelastic domains. Wafer curvature measurements in combination with x-ray diffraction stress measurements in the Ir bottom electrode showed that the as-deposited PZT films are, within experimental error, stress free at room temperature. Landau–Ginbzurg–Devonshire formalism was used to explain the origin of the rhombohedral phase as a result of substrate constraint on single domain PZT grains. Annealing was found to affect the relative volume fractions of the rhombohedral and tetragonal phases and the electrical properties of PZT films. Intermediate temperature anneals increased the volume fraction of the rhombohedral phase and the coercive field extracted from the polarization-electric field hysteresis loops. After a high temperature anneal (650 °C) the majority of the grains transformed into a polydomain state, decreasing the volume fraction of the rhombohedral phase and the coercive field. If the high temperature anneal was performed after deposition of the top electrode, the coercive field became independent of the PZT thickness. © 2003 American Institute of Physics.
Show PACS
77.55.-g Dielectric thin films
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
77.80.Dj Domain structure; hysteresis
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
68.55.-a Thin film structure and morphology
84.32.Tt Capacitors
77.22.Ej Polarization and depolarization
85.50.-n Dielectric, ferroelectric, and piezoelectric devices

Allowed mesoscopic point group symmetries in domain average engineering of perovskite ferroelectric crystals

D. M. Hatch, H. T. Stokes, and W. Cao

J. Appl. Phys. 94, 5220 (2003); http://dx.doi.org/10.1063/1.1611634 (8 pages) | Cited 2 times

Online Publication Date: 30 September 2003

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In multivariant systems, several energetically degenerate low temperature domain states can be produced at the structural phase transition. Coexistence of these domain states can produce mesoscopic structures that possess symmetries distinct from the microscopic single domain crystal symmetry. Such engineered domain structures in certain ferroelectric materials have been proven to give superior piezoelectric properties and extremely soft shear moduli. The objective of this article is to consider the variety of symmetries that can be produced through domain average engineering in proper ferroelectric systems arising from the cubic Pmmathm symmetry perovskite structure. © 2003 American Institute of Physics.
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77.80.Dj Domain structure; hysteresis
61.50.Ah Theory of crystal structure, crystal symmetry; calculations and modeling
77.80.B- Phase transitions and Curie point

Improved ferroelectric and pyroelectric properties in Mn-doped lead zirconate titanate thin films

Q. Zhang and R. W. Whatmore

J. Appl. Phys. 94, 5228 (2003); http://dx.doi.org/10.1063/1.1613370 (6 pages) | Cited 47 times

Online Publication Date: 30 September 2003

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We have investigated the effects of Mn doping on the ferroelectric and pyroelectric properties of Pb(Zr0.3Ti0.7)O3 (PZT) thin films on substrates Pt/Ti/SiO2/Si. The Mn-doped (1 mol %) PZT (PMZT) showed almost no hysteretic fatigue up to 1010 switching bipolar pulse cycles, coupled with excellent retention properties. We present evidence that while a low permittivity interfacial layer forms between the Pt electrode and PZT films, this does not occur in PMZT. We propose that Mn dopants are able to reduce oxygen vacancy mobility in PZT films and Mn2+ ions consume the oxygen vacancies generated during repeated switching, forming Mn4+ ions. These mechanisms are probably responsible for their low observed fatigue characteristics. Mn doping brings additional benefits to the electrical properties of PZT films. The relevant pyroelectric coefficients (p) of a 700 nm thick film are 3.52×10−4 C m−2 K−1 and detectivity figures of merit FD=3.85×10−5 Pa−0.5 at 33 Hz for Mn-doped PZT, compared with p=2.11×10−4 C m−2 K−1 and FD=1.07×10−5 Pa−0.5 for the undoped PZT films. This means that the Mn-doped PZT thin films are excellent candidates as device materials for both memory and pyroelectric applications. © 2003 American Institute of Physics.
Show PACS
77.55.-g Dielectric thin films
77.80.Fm Switching phenomena
77.70.+a Pyroelectric and electrocaloric effects
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
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