Pronin Igor

• Doctor of Sciences
• Senior Researcher at Russian Academy of Sciences

Исследованы латеральный пьезоэлектрический отклик и Кельвин-мода отдельных перовскитовых островков, различающихся радиально-лучистой сферолитовой микроструктурой, в тонких пленках цирконата-титаната свинца. Показано, что сферолитовые островки радиально поляризованы, что связывается с изменением плотности фаз при кристаллизации перовскитовой фазы из...

Various diagnostic techniques aimed at studying the structure and physical properties (synchronous thermal analysis, atomic force microscopy operating in the current measurement mode, electron-probe X-ray spectral microanalysis, dynamic method for determining the pyroelectric response) were used to study the crystallization features and physical pr...

В работе показано, что образование лучистой сферолитовой микроструктуры в тонких пленках цирконата-титаната свинца, полученных методом высокочастотного магнетронного распыления, сопряжено с формированием радиальных растягивающих механических напряжений, действующих в плоскости подложки, величина которых возрастает с увеличением линейного размера сф...

An experimental study of the crystal structure and ferroelectric properties of <110>-textured lead zirconate titanate films with a fine variation in their composition (with a change in the elemental ratio of zirconium and titanium atoms within 1.5%) near the morphotropic phase boundary revealed jump-like changes in the pseudocubic lattice parameter...

An experimental study of the crystal structure and ferroelectric properties of <110>-textured lead zirconate titanate films with a fine variation in their composition (with a change in the elemental ratio of zirconium and titanium atoms within 1.5%) near the morphotropic phase boundary revealed jump-like changes in the pseudocubic lattice parameter...

The features of the microstructure of radiant spherulites in lead zirconate titanate thin films are studied using scanning electron and nonlinear optical microscopy by varying the blocks size of the perovskite structure. It is shown that with an increase in the radius of the spherulite (or the size of blocks), the angle of rotation of the growth ax...

In solid solutions of Na1/2Bi1/2TiO3-xBaTiO3, the question of the relationship between the concentration of BaTiO3(x) and the presence of relaxor properties, as well as at what value of x these properties disappear, was studied. For this purpose, dielectric measurements of polarized and unpolarized compounds were carried out in a wide range of conc...

Рассмотрено влияние линейных и изгибных напряжений на величину внутреннего поля и самополяризации в тонких пленках цирконата-титаната свинца (PZT), сформированных методом высокочастотного магнетронного распыления на подложках кремния и ситалла СТ-50. Состав тонких пленок соответствовал области морфотропной фазовой границы. Предположено, что изгибны...

This work presents the results of a comparative study of dielectric and pyroelectric properties of aluminum nitride (AlN) single-layer and multilayer samples with a thickness of 100 ÷ 200 μm grown in the [0001] direction by chloride-hydride epitaxy. A silicon wafer covered by silicon carbide nanolayer grown by solid-phase substitution (SiC/(111)Si)...

The microstructure and pyroelectric properties of AlxGa1-xN composite epitaxial layers grown on SiC/Si(111) and SiC/Si(110) hybrid substrates by the chloride-hydride epitaxy have been studied. The phenomenon of spontaneous formation of a system of heterojunctions consisting of periodic AlxGa1-xN layers of different composition located perpendicular...

In self-polarized lead zirconate titanate thin films formed on platinized silicon substrates, a significant increase in the internal electric field was observed as a result of long-term aging. To explain this phenomenon, a mechanism is proposed for the formation of the internal field associated with the diffusion of charged oxygen vacancies, which,...

The microstructure and pyroelectric properties of Al x Ga 1-x N composite epitaxial layers grown on SiC/Si(111) and SiC/Si(110) hybrid substrates by the chloride-hydride epitaxy have been studied. The phenomenon of spontaneous formation of a system of heterojunctions consisting of periodic Al x Ga 1-x N layers of different composition located perpe...

In self-polarized lead zirconate titanate thin films formed on platinized silicon substrates, a significant increase in the internal electric field was observed as a result of long-term aging. To explain this phenomenon, a mechanism is proposed for the formation of the internal field associated with the diffusion of charged oxygen vacancies, which,...

The paper discusses the possibility of a fine variation in the composition of submicron ferroelectric films of lead zirconate titanate solid solutions corresponding to a morphotropic phase boundary. Composition was varied by changing the distance from the target to the substrate in the range of 30-70 mm in an installation for radio-frequency magnet...

The article discusses the possibilities of fine composition variation of polycrystalline PZT films at the morphotropic phase boundary. The composition of thin films prepared by RF magnetron sputtering of a ceramic target of stoichiometric composition PbZr0.54Ti0.46O3 was varied by changing the distance from the target to the substrate in the range...

The results of the dielectric, pyroelectric, and piezoelectric studies of aluminum nitride single crystals are presented in this paper. The crystals were grown by sublimation and hybrid-chloride vapor phase epitaxy, which provided high growth rates, large sizes, and the ability to reduce structural defects. The pyroelectric effect measurements by a...

The microstructure, dielectric, and pyroelectric properties of AlxGa1-xN composite epitaxial layers grown on SiC / (111) Si substrates by chloride-hydride epitaxy are studied. In the process of layer growth, the phenomenon of spontaneous formation of heterojunctions was discovered. Based on AlxGa1-xN epitaxial layers, a material has been obtained w...

The relaxation processes in polycrystalline PZT films formed on silicon substrates have been studied during a quasi-static change in an external electric field. The dielectric relaxation is shown to be characterized at least by three relaxation times depending on the direction of the self-polarization in the film, the value of the polarizing field,...

A comparative study of the morphology and piezoelectric response of island and continuous perovskite thin PZT films deposited on a platinized silicon substrate Si/SiO2/TiO2/Pt was carried out. It was shown that the self-polarization value of micron-size island films was about 1.4 times higher than that of continuous films. It is assumed that the di...

Dielectric and polar properties of aluminum nitride (AlN) thin films epitaxially grown on differently oriented silicon substrates with the p-type conduction and a buffer silicon carbide (SiC) layer and on vicinal planes are investigated. The results of studies of the polar properties by two independent methods—the dynamic pyroelectric effect and th...

The barrier properties of a capacitor heterostructure based on a ferroelectric lead zirconate-titanate were investigated by using the methods of current-voltage and voltage-capacitance characteristics. The variable values of the potential barrier on the PZT-Pt interface were determined by the C-V method (from 0.5 to 1.6 eV) and the I-V method (from...

Two-layer thin films of lead zirconate titanate (PZT) with lead content in the layers differing by 20% were deposited by RF magnetron sputtering at variable working gas pressure in the system. The phase states, compositions, and dielectric properties of two-layer films obtained with different orders of layer deposition were compared. It is establis...

The element composition modification is experimentally studied in PZT thin films obtained via the RF magnetron sputtering with variable working gas pressure. The experimental data were interpreted through the statistic simulation of thermalization and diffusion of sprayed Pb, Zr, and Ti atoms during the ion-plasma deposition of PZT thin films. The...

The paper presents the results of studies of bilayer thin ferroelectric PZT films with a lead content variation on the films thickness, formed by the method of radio-frequency magnetron deposition at different pressures of the gas mixture. It was shown that, depending on the sequence of deposition of the layers, both the structure and the dielectri...

Surface topography, dielectric and pyroelectric properties of semipolar AlN thin films are studied. The growth of AlN was carried out by hydride-chloride vapor phase epitaxy on hybrid SiC layers specially prepared for the growth of semipolar AlN layers. SiC layers were grown on Si substrates of p-type (KDB) with (100)-orientation. The dynamic pyroe...

In this work, the electrical properties of SiC epitaxial films grown on single-crystalline silicon substrates with conductivity of n- and p-types were studied. It was shown that the electric response of these films to light irradiation in the wavelength range 400–980 nm had a photovoltaic nature. The photon energy of the irradiation was smaller tha...

It is established that the magnetron sputtered thin PbZr54Ti46O3 (PZT) films contain a certain amount of pores, which makes it impossible to investigate their properties by traditional methods. It is shown that the boundaries of polycrystalline blocks in PZT films have an increased values of appearing transient currents associated with grain bounda...

Variation of the working gas pressure (from 8 to 2 Pa) during RF magnetron sputtering deposition of thin perovskite lead zirconate titanate (PZT) films revealed strong changes in their lead content, which decreased below the stoichiometric level and led to the formation of a two-phase (perovskite–pyrochlore) structure upon subsequent high-temperatu...

Variation of the working gas pressure (from 8 to 2 Pa) during RF magnetron sputtering deposition of thin perovskite lead zirconate titanate (PZT) films revealed strong changes in their lead content, which decreased below the stoichiometric level and led to the formation of a two-phase (perovskite–pyrochlore) structure upon subsequent high-temperatu...

Two-layer thin lead zirconate titanate films in which the lead content differed by 20% were formed by radio-frequency magnetron deposition under variation of the working gas pressure. A comparative study of the phase state, composition, and dielectric properties of bilayer structures differing in the sequence of layers deposition has been carried o...

The features of the microstructure and piezoelectric response of perovskite islands in the matrix of the pyrochloric phase in thin lead zirconate titanate films formed by the method of radio-frequency magnetron sputtering are investigated. The radial heterogeneity of the surface morphology of the islands and the piezoelectric response is revealed....

The relationship between the microstructure, composition, phase state, and dielectric properties with a change in the distance from the target to the substrate (in the range 30–70 mm) was studied for high-frequency magnetron deposition of thin layers of lead zirconatetitanate (PZT). The composition of the sputtered target of the solid solution of P...

It is shown that the character and orientation of a self-polarization depends on the superstoichiometric amount of lead in thin Pb(Zr1-xTix)O3 films (x = 0.46) formed on a Pt/TiO2/SiO2/Si substrate by a two-stage RF-magnetron sputtering (ex-situ) method. The lead content was changed by varying the pressure of the working Ar+O2 mixture in the range...

The paper presents the results of a study of dielectric and photovoltaic properties of heterostructures SiC / Si with different conductivity type of silicon substrates. The stationary photovoltaic responses of the structures were observed under electromagnetic radiation in the wavelength range from 400 — 980 nm. It is shown that the phase of photov...

The article presents the effect of technological parameters of RF magnetron sputtering on the concentration of components of thin-film ferroelectric structures based on lead zirconate titanate PZT in the region of the morphotropic phase boundary. It is shown that by changing the distance from the target to the substrate and the pressure of the work...

We investigated the behavior of the capacitance and dielectric loss tangent under bias voltage in Pt/PZT/Pt thin film structures annealed at 540–570°C. Internal field in PZT films was determined on a basis of C-V characteristics. Also, the frequency dependence of the dielectric response of these films was obtained. A correlation between dielectric...

The phase state of lead-zirconate-titanate thin films, obtained by a two-stage technology, at the morphotropic phase boundary is studied by electron backscatter diffraction and by measuring the temperature dependence of their dielectric constant. It is shown that depending on the working-gas pressure and the heat-treatment temperature, the volume r...

The influence of the pressure of the argon-oxygen gas mixture on the composition of Pb(Zr,Ti)O3 (PZT) films deposited by RF magnetron sputtering on the silicon substrate with a platinum layer has been studied. It was demonstrated that the change in the self-polarization vector is unambiguously associated with the variations of the concentration of...

Explosive crystallization (EC) of materials has been extensively studied both theoretically and experimentally in the end of 20 th century. Now EC can be used for investigations of fast phase transitions [1] and controlled fabrication of heterostructures, for example, by the laser annealing [2]. In this case, location of the heat source depends on...

The factors responsible for the change in the orientation of the natural unipolarity vector due to heating to the Curie temperature of a Pt/PZT/Pt thin-film capacitor (PZT—lead zirconate titanate) formed on a TiO2/SiO2/Si substrate have been considered. Lead zirconate titanate thin layers containing a small excess of lead oxide have been formed ex...

Dielectric response of thin-film capacitor structures of Pt/PZT/Pt deposited by the RF magnetron sputtering method and annealed at temperatures of 540–570 °C was investigated. It was found that dielectric properties of these structures depend on the synthesis temperature. Stability of a polarized state is considered on the basis of the analysis of...

BZT and BTS thin films were fabricated in-situ by RF magnetron on Pt/Ti/Al 2 O 3 substrate (r-cut) in oxygen atmosphere. All films with thickness 400 to 500 nm were crystallized in perovskite phase. For the electrical studies the sandwich capacitors were fabricated based on BZT and BTS films. Tunability at 20 V reached 3.5 with dielectric losses as...

Thin films of BaSnxTi1-xO3 composition (Sn/Ti ≈50/50) are grown in-situ by RF magnetron deposition onto Pt/Ti/Al2O3 substrate. Structural and dielectric properties are optimized by changing substrate temperature. Best thin-film samples have shown a high tunability (about 3.5) and low dielectric losses attractive for microwave electronics.

This paper presents the results of pyroelectric and piezoelectric studies of AlN films formed by chloride–hydride epitaxy (CHE) and molecular beam epitaxy (MBE) on epitaxial SiC nanolayers grown on Si by the atom substitution method. The surface topography and piezoelectric and pyroelecrtric responses of AlN films have been analyzed. The results of...

Thin ferroelectric Bax Sr1–x TiO3 (BST) layers have been grown for the first time on semi-insulating silicon carbide substrates by RF magnetron sputtering of a ceramic target without using buffer sublayers. Results of investigation of the structure of obtained BST films and the electrical properties of related planar capacitors are presented. The o...

Submicron thin layers of BaZrx Ti1–x O3 are grown in-situ by RF magnetron sputtering of a ceramic target (x = 0.50) on a substrate of Pt/r-cut leucosapphire Al2O3. It is shown that the composition of the ferroelectric layer is not identical to the composition of the sputtered target and is shifted toward barium zirconate. The reasons for such behav...

Рассматриваются причины изменения ориентации вектора естественной униполярности в результате нагревания до температуры Кюри тонкопленочного конденсатора Pt/PZT/Pt (PZT --- цирконат-титанат свинца), сформированного на подложке TiO 2 /SiO 2 /Si. Тонкие слои PZT, содержащие незначительный избыток оксида свинца, сформированы ex situ методом высокочасто...

The features of microstructure crystallization into perovskite phase in lead zirconate titanate film by femtosecond laser radiation of near-infrared range were discussed. In-situ crystallization kinetics by method of second harmonic generation (SHG) was studied. The presence of several types of crystallization was shown, including ultra-fast (explo...

The crystallization in a transparent precursor of a perovskite ferroelectric film deposited on an absorbing platinized silicon substrate initiated by multipulse femtosecond sharply focused laser beam of near-infrared spectral range is studied by transmission electron microscopy. Time dependences of the shapes of crystallized areas point to initiati...

It has been shown that 300-nm-thick polycrystalline films of lead zirconate titanate (PZT), the compositions of which correspond to the region of morphotropic phase boundary, undergo anomalous changes in the composition and the microstructure as the annealing temperature increases. This causes substantial variations in the dielectric and piezoelect...

Features of crystallization of microstructures to the perovskite-like phase in a lead zirconate titanate film are studied using multiple near-IR femtosecond laser pulse radiation. The kinetics of crystallization is in situ investigated using the second-harmonic generation technique. It is established that the crystallization is divided into high-te...

Submicron ferroelectric PZT films deposited on the Pt/TiO2/SiO2/Si substrate by RF magnetron sputtering and annealed at 530–570 °C consisted of spherulitic blocks with crosswise size of ~5-40 μm. The films composition corresponded to morphotropic phase boundary. The spherulite sizes, excess lead oxide content, the dielectric constant, self-polariza...

Structural characterization of the epitaxial thin aluminum nitride (AlN) 1-mu m-thick films grown on SiC/(111)Si substrate by molecular beam epitaxy method was done. The films are shown to be single crystals of (0002) orientation with parameter full width half maximum FWHM omega(theta) = 0.5 degrees. A comparative study of the film electrical prope...

An accuracy of elemental composition of submicron PZT films was investigated using nondestructive method of the electron probe X-ray microanalysis based on energy dispersive analyzer. PZT films RF-magnetron sputtered on Pt/SiO2/Si substrate were annealed to create the perovskite phase in the temperature range of 530-570°C. Unusual changes of lead c...

It has been shown that, in polycrystalline thin PZT films with the Zr/Ti = 0.535/0.465 ratio of ions in octahedral positions of the perovskite structure, the permittivity and the pyroelectric and piezoelectric responses increase with increasing linear sizes of growth blocks to reach anomalously large values. It has been assumed that the observed ef...

Single crystals of Na1/2Bi1/2TiO3-KTaO3 (NBT-KT) solid solutions have been grown for the first time. The elemental composition of as-grown single crystals determined by X-ray diffraction corresponds to 0.81 NBT-0.19 KT. Measurements of the temperature dependences of dielectric characteristics showed that the obtained NBT-KT crystals possess clearly...

Electrical conductivity and dielectric characteristics in Pt/Pb(Zr0.54,Ti0.46)O3/Pt film structures synthesized at different temperatures are studied. Current-voltage (I–V) and capacity-voltage (C–V) characteristics are obtained. Asymmetry of the I–V characteristics is revealed, indicating a difference in the potential barriers at the interfaces of...

We have studied changes in the dielectric properties of thin lead zirconate titanate Pb(Zr,Ti)O3 (PZT) films, obtained using a two-stage ex-situ technology, as dependent on the microstructure of a perovskite phase and the content of microinclusions of excess lead oxide. The presence of these microinclusions leads to either anomalously low or high v...

A study has been performed of the mechanisms underlying evolvement of excess lead oxide from lead zirconate titanate films grown ex-situ in two different regimes by magnetron sputtering. In the first case, crystallization of the dense phase of perovskite passed through an intermediate “porous” phase, and in the second, straight through. It has been...

The study of conductivity of thin film capacitor structures on the basis of PZT was carried out. The obtained asymmetry of I-V characteristics showed the distinction of potential barrier height on interfaces of the Pt/PZT/Pt heterostructures, which changed depending on synthesis conditions. Time dependences of the electric current on DC voltage wer...

This paper presents an experimental study of the pyrochlore-to-perovskite phase transition in ferroelectric lead zirconate titanate (PZT) films grown on silicon substrates by rf magnetron sputtering and annealed in air or in an inert (argon) atmosphere at temperatures of up to 600°C and atmospheric pressure. Simultaneous thermal analysis results de...

The quazi-amorphous PbZrTiO2 (PZT) precursor film on a platinized silicon substrate is annealed by femtosecond laser at the wavelength falling into transparency band of PZT. Two areas are found within the laser spot: ferroelectric perovskite revealing strong hysteresis and coercivity in piezoelectric response and paraelectric with low piezoresponse...

The phase transformation from the pyrochlore phase into the perovskite phase in ferroelectric films of lead zirconate titanate on silicon substrates due to annealing of samples has been investigated experimentally and theoretically. It has been proved that this transformation is a typical first-order phase transition, which is accompanied by a chan...

Ti-sapphire femtosecond laser was utilized to crystallize Pb(Zr0:54Ti0:46)O3 (PZT) film on platinized silicon substrate. Second harmonic generation was used to in-situ monitor of the annealing process and to confirm a non-centrosymmetric perovskite ferroelectric phase of the irradiated area. The images of the film surface after laser exposure were...

Parameters characterizing diffuseness of ferroelectric phase transitions in (1-x) PbMg1/3-Nb2/3O3(PMN) + xPbTiO3(PT) and (1–x)PMN+xPb(Ni1/3Nb2/3)O3 (PNN) solid solutions are investigated. Experimental methods of their evaluation are discussed. The relationship between different diffuseness parameters of the systems is clarified and discussed.

The conductivity of thin-film Pt/PZT/Pt structures has been studied using the method of current-voltage characteristics. The asymmetry of current-voltage characteristics has been revealed, which indicates that the potential barriers at the interfaces between the studied structures are different, and this asymmetry changes depending on the condition...

The thermodynamics of processes involved in the growth and annealing of ferroelectric films of lead zirconate titanate Pb(Ti,Zr)O3 (PZT) has been studied using the method of synchronous thermal analysis (STA). Thin PZT films were grown by the RF magnetron sputtering and then annealed in air or in an inert gas (argon) at atmospheric pressure and var...

The structure and dielectric properties of thin lead zirconate titanate Pb(Zr,Ti)O3 films grown ex situ on a silicon substrate are studied using various methods (X-ray analysis, raster electron microscopy, atomic-force microscopy, optical microscopy, and dielectric measurements). It is shown that, upon increase in the crystallization temperature, t...

Inclusions of lead oxide in ex-situ grown PZT thin films are known to give rise to a phenomenon of self-polarization. It is shown that dependence of self-polarization on thickness in the films deposited on glass ceramic/Pt substrate differ substantionally from that for ones deposited on Si/SiO2/Pt substrate. Different behaviour of curves is discuss...

In the work, “ex-situ” prepared PZT films were deposited on Pt/Ti/SiO2/Si and Pt/Ti/pyroseram substrates by rf magnetron sputtering of PZT ceramic targets additionally containing excess lead oxide. An unusual “beak” shape of pyroelectric and piezoelectric hysteresis loops measured by “remanent hysteresis” regime were studied upon application of str...

The structure and dielectric properties of thin lead zirconate titanate films grown ex situ on Pt/SiO2/Si substrates were studied. It was shown that with a crystallization temperature increase in the range of 540 to 580°C, the mechanism of perovskite phase growth changes and the ferroelectric parameters change according to this transformation.

This paper reports on a study of crystallization of thin lead zirconate-titanate films deposited on Si/SiO2/Pt substrates by RF magnetron sputtering at a low temperature and annealed at 540–580°C. In this temperature interval, one observes successively two first-order phase transitions: the low-temperature pyrochlore phase—perovskite-I phase and pe...

Structures of the transparent ferroelectric field-effect transistor PZT/SnO2/Al2O3 with ``normal'' and ``anomalous'' conductivity hystereses of the channel are prepared and investigated. The ``normal'' modulation loop for these structures is obtained for the first time. Antimony-doped SnO2/Al2O3 epitaxial films evaporated by a YAG laser from a meta...

A new thin-film structure representing the Pt/PZT/SiC/Si system is obtained. The structure comprises a lead zirconate titanate Pb(Zr,Ti)O3 (PZT) film deposited onto thin (90–100 nm) single crystal silicon carbide layers of 3C-SiC and 4H-SiC polytypes grown by a new solid-phase epitaxy on single crystal silicon substrates. Methods used for the form...

Piezo- and pyroelectric hysteresis loops have been studied in unipolar lead zirconate titanate (PZT) films grown on silicon substrates. The PZT film compositions corresponded to the region of a morphotropic phase boundary. It is established that the degree of unipolarity (spontaneous polarization) in such films can reach a level that is close to th...

Comparative analysis of pyroelectric and piezoelectric hysteresis loops of thin PbZr0.54Ti0.46O3 + 10 mol % PbO films formed under the same conditions on pyroceram and silicon substrates has been performed. The significant differences in the behavior of the parameters under study are attributed to the different character of the biaxial stress actin...

We studied a PbxZr1−xTiO3/SnO2/Al2O3 heterostructure as a base for transparent ferroelectric field-effect transistor. Single-crystal SnO2/Al2O3 epitaxial films with the electron mobility of 25 cm2/V were grown by pulsed laser deposition using two YAG:Nd lasers. Depletion mode transistor Au/PZT/SnO2/Al2O3 was produced by laser ablation and RF sputte...

The influence of 0.63-μm laser radiation and an external electric field on the photo-and pyroelectric response of thin ferroelectric Pb(Zr0.54Ti0.46)O3 (PZT) films is studied at various temperatures. The films are grown by RF magnetron sputtering of a PZT ceramic target on platinum-coated substrates. It is found that the photosensitivity of PZT fil...

The nature and mechanisms of formation of the spontaneous polarization arising in thin ferroelectric films in the course of formation of a thin-film capacitor structure and relaxation of this polarization under the action of an electric field, temperature, and illumination are discussed.

The possibility of fabrication of a transparent ferroelectric field effect transistor (FFET) with a high electron mobility channel was demonstrated. The highest obtained electron mobility in the channel SnO 2 /c-Al 2 O 3 is 25 cm 2 /V·s and SnO 2 /r-Al 2 O 3 is 40 cm 2 /V·s at the electron density of 10 19 –10 20 cm −3 . A transparent FFET structur...

The possibility of fabricating a ferroelectric FET based on a Pb(ZrxTi1−x )O3/SnO2 (PZT/SnO2) heterostructure is investigated. Sb-doped epitaxial SnO2/Al2O3 thin film deposited by YAG laser ablation from a metal target is used as the FET channel. The highest obtained electron mobility in the channel is 25 cm2/(V s) at an electron density of 8 × 101...

We have studied the effect of optical radiation on the conductivity of a thin film field effect transistor based on a Si-SiO2-Pt-PZT-SnO2− x-Pt multilayer structure. Within an admissible radiation dose, the conducting channel possesses a persistent photoconductivity, with an optical data storage time of at least 10s. Effective channel impedance con...

Pyroelectric hysteresis in unipolar lead zirconate titanate (PZT) films was studied upon preliminary poling in a strong external electric field and immediately in the applied external field. The asymmetry of the observed hysteresis loops is considered within the framework of an electromechanical approach to the phenomenon of natural unipolarity (sp...

Self-polarization effect was observed in Pb(Zr0.54Ti0.46)O-3 (PZT) films with 10 mol% of PbO excess RF magnetron sputtered onto Pt/Ti/SiO2/Si substrates. On the contrary, no self-polarization was found in films sputtered from stoichiometric targets. Local piezoelectric measurements revealed the asymmetry in the piezoelectric distributions of self-p...

We have studied the effect of optical radiation on the conductivity of a thin-film field-effect transistor based on a multilayer structure of the Si-SiO2-Pt-PZT-SnO2−x -Pt type. Within the permissible radiation dose, the conducting channel exhibits a residual photoconductivity, with an optical data storage time of no less than 105 s. The effective...

A model of mechanical stresses acting upon a ferroelectric film in a thin-film capacitor structure of the Si-SiO2-Pt-PZT-Pt type is proposed. An analysis of this model showed that, in most cases, thin PZT films with thicknesses within 100-200 nm (used in the elements of NVFRAM devices) are subjected to tensile stresses. It is suggested that replaci...

The effect of stresses, appearing due to a difference between the temperature coefficients of linear expansion of a substrate and ferroelectric film, on the self-polarization is discussed using thin films of lead zirconate-titanate PbZrxTi1−x O3 (PZT) of different compositions as an example. It is assumed that the nature of self-polarization is con...

It is shown that high-temperature treatment of self-poled lead zirconate-titanate films containing an excess of lead oxide, followed by prolonged storage at room temperature, results in a charge redistribution in the near-electrode regions of ferroelectric films. Such heat treatment destroys, as a rule, the self-poled state and removes the dielectr...

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...

Electrical properties of 1- w m-thickness preferentially <111>-oriented PZT ferroelectric films of rhombohedral composition near the morphotropic boundary prepared by RF magnetron sputtering of a ceramic target containing additionally 10 mol % lead oxide were studied. The data obtained suggests n -type conductivity due to lead oxide excess in the f...