Method of forming polydomain ferroelectric monocrystals with charged domain wall |
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IPC classes for russian patent Method of forming polydomain ferroelectric monocrystals with charged domain wall (RU 2485222):
     
 Method of making acoustooptical modulators / 2461097
Acoustic line is made in form of a rectangular prism. Further, optically antireflecting coatings are deposited via vacuum deposition onto the faces of the rectangular prism. A first adhesive layer is then deposited on one of the faces of the rectangular prism by vacuum deposition. Using vacuum deposition, a first gold layer is deposited on said first adhesive layer. Further, a first indium layer is deposited on said first gold layer by vacuum deposition. Also, using vacuum deposition, a second adhesive layer is deposited on one of the larger faces of each of two plates made from lithium niobate of the (Y+36°)-section. Using vacuum deposition, a second gold layer is then deposited on said second adhesive layer. Using vacuum deposition, a second indium layer is deposited on said second gold layer. The acoustic line is the joined with the lithium niobate plates by pressing the lithium niobate plates with the pressure of each lithium niobate plate of the second indium layer to the corresponding first indium layer. Each of the lithium niobate plates is then ground off to the required thickness which corresponds to the operating frequency band. Using vacuum deposition, a third adhesive layer is deposited on each free large face of each lithium niobate plate. A third gold layer is then deposited on said third adhesive layer via vacuum deposition. The method is characterised by that the acoustic line material used is a TeO2 monocrystal, wherein the faces of the rectangular prism are directed perpendicular to the crystallographic direction [001],
 Method for machine-tool manufacture of shear measuring transducer / 2436105
At the first stage of manufacture preparation of component parts and assemblies takes place that is manufacture of an armour ring of spring steel, of a ring nozzle with a conic external facet of a tungsten alloy, a titanium hexagonal foundation and a cup-type body with a coaxial connector or a cable. The second stage involves fixation of the assembly in the vertical axial fixture of the electroerosion wire-cutting machine-tool, making three vertical grooves in fixed positions, mounting sensor elements, press-fitting or hot shrink fit of the armour ring on the ring nozzle with piezoelectric elements, making horizontal radial sections under the armour ring for an inertial mass formation and installation and fixation of the body and connection to the outlet of the preliminary amplifier of the connector.
Method of removing organic residue from piezoelectric substrates / 2406785
Method involves evacuation and treating substrates in oxygen-containing plasma. Substrates are treated in a plasma mixture of oxygen and inert gas containing 5-12 vol. % oxygen and 88-95 vol. % inert gas. The inert gas is helium, neon or argon and treatment is carried out at temperature in the reaction chamber equal to 80-140 Pa, radio-frequency power equal to 0.02-0.06 W/cm3 and exposure time of 3-15 minutes.
Method of making quartz-crystal resonators with linear temperature-frequency characteristic / 2366037
Invention relates to the technology of making piezoelectric resonators and can be used for making quartz-crystal temperature sensitive piezoelectric sensors, used as precision measuring devices. The method involves depositing metal electrodes on the surface of an AT-cut piezoelectric plate, mounting the obtained piezoelectric element on a base, and tuning the resonance frequency of the piezoelectric resonator. After each operation thermal processing is done in isopropyl alcohol at liquid nitrogen temperature. After cooling the piezoelectric resonator is heated in a sealed capsule while letting in insulating gas under pressure.
 Method for improving temperature and frequency characteristics of glass-packaged crystal resonators / 2308790
Piezoid is exposed to focused pulse radiation of laser beyond disposition region of electrodes at Q-factor modulation with energy density in laser beam constriction exceeding laser destruction threshold of crystal piezoid to produce microscopic destruction therein measuring 30 to 100 μm. Impact points are chosen at distance L = (3t + 0.5) mm from piezoid electrode edge, where t is piezoid thickness in millimeters. Laser radiation energy density is below laser destruction threshold of resonator glass package residing beyond laser beam constriction region.
 Piezoelectric transducer and its manufacturing process / 2258276
Proposed piezoelectric transducer has two identical insulating wafers made of ferroelectric piezofilm. Each wafer has separate polarized region with electrodes disposed on its opposing surfaces that functions as sensing element of transducer. Polarization vector of wafers is perpendicular to electrodes. Measuring current leads in the form of plane-parallel strips are deposited on opposing surfaces of piezofilm and electrically connected to electrodes. Both wafers are connected through their surfaces to unipolar electrodes symmetrically to one another. External and internal measuring current leads formed in this way are electrically interconnected in pairs and their transverse dimensions are chosen from expression α > w + 2b, where α is width of external current leads; w is width of internal current leads; b is distance between external and internal current leads. Proposed process for manufacturing piezoelectric transducer includes formation of transducer sensing element by separating desired region on insulating wafer made of ferroelectric piezofilm, disposition of electrodes on its opposing surfaces, and deposition of measuring current leads in the form of plane-parallel strips electrically connected to electrodes onto opposing surfaces of wafer. Two identical wafers are connected through their surfaces to unipolar electrodes symmetrically to one another. Measuring current leads are formed on each wafer by enlarging areas of respective electrodes. External and internal measuring current leads are electrically interconnected in pairs.
 The way the separate determination of acetone and ethyl acetate in the air / 2204126
The invention relates to analytical chemistry of organic compounds and can be used for the analysis of gaseous emissions from the production of dyes
 The way to create a modifier electrodes piezoquartz resonator for the detection of vapors of organic substances in the air / 2163374
The invention relates to analytical chemistry of organic compounds (detection and analysis) and can be used for the analysis of gaseous emissions of enterprises, in particular, to determine the concentration of aniline
A method of manufacturing an acoustic transducer / 2122260
The invention relates to methods for producing acoustic transducers, mainly piezoceramic ultrasonic transducers, the distinguishing feature of this method is the setting of the acoustic transducer at an optimum frequency response by adjusting the geometry of the membrane
 Bimorph piezoelectric seismogenic and the method of obtaining identical bimorph piezoelectric vibration detectors / 2119678
The invention relates to seismometry and can be used in seismology for control and measurement of vibration parameters of soil on land and in the sea, caused by artificial or natural sources of vibration
 Method of diamond heat treatment / 2471542
Invention relates to processes used in operation at high pressure and modifying substances physically. Proposed method comprises placing diamond in reaction cell in pressure transmitting medium, increasing pressure in reaction chamber and it cooling. Note here that thermal treatment is carried out at temperature increase rate of 10-50°C/s and at 2000-2350°C by passing electric current via heater in cell from programmed power supply source with due allowance for temperature relaxation in said cell in heating. For this, note also that temperature relaxation constant is defined. Said cell is cooled after heating by switching off power supply in forming short diamond heating pulse in temperature range of over 2000°C with diamond total stay time smaller than 30 seconds. Allowance for temperature relaxation in said cell in heating for heating rate Vt and pre-definition of cell temperature relaxation constant τ is made by setting in said programmable power source the maximum temperature of heating to τVT above maximum treatment temperature of 2000-2350°C.
 Method of forming optically permeable image inside diamond, apparatus for realising said method (versions) and apparatus for detecting said image / 2465377
Inside a diamond, in the region free from optically impermeable irregularities, an image is formed, which consists of a given number of optically permeable elements of micrometre or submicrometer size, which are clusters of N-V centres which fluoresce in exciting radiation, wherein formation of clusters of N-V centres is carried out by performing the following operations: treating the diamond with working optical radiation focused in the focal region lying in the region of the assumed region where the cluster of N-V centres is located, while feeding working ultrashort radiation pulses which enable to form a cluster of vacancies in said focal region and which provide integral fluence in said focal region lower than threshold fluence, where there is local conversion of the diamond to graphite or another non-diamond form of carbon; annealing at least said assumed regions where clusters of N-V centres are located, which provide in said regions drift of the formed vacancies and formation of N-V centres, grouped into clusters in the same regions as the clusters of vacancies; controlling the formed image elements based on detection of fluorescence of N-V centres by exposing at least regions where image elements are located to exciting optical radiation, which enables to excite N-V centres and form a digital and/or a three-dimensional model of the formed image. Images formed in diamond crystals from clusters of N-V centres are visible to the naked eye, by a magnifying glass and any optical or electronic microscope.
 Method of producing diamond structure with nitrogen-vacancy defects / 2448900
Invention can be used in magnetometry, quantum optics, biomedicine and information technology. Cleaned detonation nanodiamonds are sintered in a chamber at pressure 5-7 GPa and temperature 750-1200°C for a period time ranging from several seconds to several minutes. The obtained powder of diamond aggregates is exposed to laser radiation with wavelength smaller than 637 nm and diamond aggregates with high concentration of nitrogen-vacancy (NV) defects are selected based on the bright characteristic luminescence in the red spectral region. In the obtained diamond structure, about 1% of carbon atoms are substituted with NV defects and about 1% of carbon atoms are substituted with single nitrogen donors.
 Method of cleaning large crystals of natural diamonds / 2447203
Method involves step-by-step treatment of diamonds in an autoclave at high temperature and pressure, including a step for cleaning with a mixture of nitric acid and hydrogen peroxide and a step for cleaning with a mixture of concentrated nitric, hydrochloric and hydrofluoric acids under the effect of microwave radiation. After the step for cleaning with nitric acid and hydrogen peroxide, the diamonds are treated under the effect of microwave radiation with hydrochloric acid in gaseous phase at temperature 215-280°C for 15-300 minutes. Further, the diamonds are treated with distilled water at temperature 160-280°C for 5-30 minutes in an autoclave in liquid phase. At the step for cleaning with a mixture of nitric acid and hydrogen peroxide, treatment is carried out with the following volume ratio of components: nitric acid and hydrogen peroxide 4-10:1-3, respectively, at temperature 215-280°C for 15-540 minutes in liquid phase in a system with external heating or in a gaseous phase under the effect of microwave radiation. At the step for cleaning with a mixture of concentrated nitric, hydrochloric and hydrofluoric acids, treatment under the effect of microwave radiation is carried out with the following volume ratio of components: nitric, hydrochloric and hydrofluoric acid 1-6:1-6:1-3, respectively, in gaseous phase at temperature 215-280°C for 15-300 minutes.
 Procedure for production of diamonds of fantasy yellow and black colour / 2434977
Procedure consists in ion-energy-beam processing diamonds with high power ion beam of inert chemical element of helium with dose of radiation within range from 0.2×1016 to 2.0×1017 ion/cm2 eliminating successive thermal annealing.
 Procedure for radiation of minerals / 2431003
Procedure for radiation of minerals in neutron flow of reactor in container consists in screening radiated minerals from heat and resonance neutrons. Composition of material and density of the screen is calculated so, that specific activity of radiated minerals upon completion of radiation and conditioning does not exceed 10 Bq/g. Before radiation contents of natural impurities in radiated minerals can be analysed by the method of neutron activation analysis. Only elements activated with resonance neutrons are chosen from natural impurities of radiated minerals. Tantalum and manganese or scandium and/or iron or chromium are used as elements of the screen. Chromium-nickel steel alloyed with materials chosen from a row tantalum, manganese and scandium are used in material of the screen.
 Device for irradiating minerals / 2406170
Device for irradiating minerals has a reactor active zone, an irradiation channel, a container and extra slow neutron filter. Inside the container there are slow and resonance neutron filters. The extra slow neutron filter surrounds the container and is fitted in the irradiation zone. A gamma-quanta absorber of the reactor is placed between the container and the active zone of the reactor. A resonance neutron absorber is added to the extra slow neutron filter. The thickness of these absorbers enables to keep temperature inside the container not higher than 200°C during irradiation.
Polarisation method of monocrystal of lithium tantalate / 2382837
Invention relates to industrial production of monocrystals, received from melt by Czochralski method, and can be used during polarisation of ferroelectrics with high temperature Curie, principally lithium tantalate. On monocrystal of lithium tantalate by means of grinding it is formed contact pad, surface of which is perpendicular to optical axis of crystal or at acute angle to it. Monocrystal is located between bottom segmental or laminar platinum electrode and implemented from wire of diametre 0.3-0.6 mm top circular platinum electrode through adjoining to its surfaces interlayers. In the capacity of material of interlayer it is used fine-dispersed (40-100 mcm) powder of crystalline solid solution LiNb1-xTaxO3, where 0.1≤x≤0.8, with bonding alcoholic addition in the form of 94-96% ethyl alcohol at mass ratio of alcohol and powder 1:2.5-3.5. Monocrystal is installed into annealing furnace, it is heated at a rate not more than 70°C/h up to temperature for 20-80°C higher than temperature Curie of monocrystal and through it is passed current by means of feeding on electrodes of polarising voltage. Then monocrystal is cooled in the mode current stabilisation at increasing of voltage rate 1.2-1.5 times up to temperature up to 90-110°C lower than temperature Curie, and following cooling is implemented in the mode of stabilisation of polarising voltage at reduction of current value through monocrystal. At reduction of current value 3.0-4.5 times of its stable value voltage feeding is stopped, after what monocrystal is cooled at a rate of natural cooling-down. Monocrystal cooling up to stop of feeding of polarising voltage is implemented at a rate 15-30°C/h.
 Method of producing mono-crystalline plates of arsenide-indium / 2344211
Invention refers to semi-conductor technology of AIIIBV type compositions. The method is implemented by means of bombarding mono-crystalline plates of arsenide-indium with fast neutrons with following heating, annealing and cooling. The mono-crystalline plates are subject to bombardment with various degree of compensation at density of flow not more, than 1012 cm-2 c-1 till fluence F=(0.5÷5.0)·1015 cm-2 , while annealing is carried out at 850÷900°C during 20 minutes at the rate of heating and cooling 10 deg/min and 5 deg/min correspondingly.
 Method of obtaining minerals and device for its realisation / 2341596
Method of obtaining minerals is realised in neutron reactor flow, minerals being placed in layers between layers of substance or mixture of substances, containing elements, absorbing thermal and resonance neutrons, layers being separated with aluminium interlayer and surrounded with filtering unit from substance or mixture of substances, containing elements, absorbing thermal and resonance neutrons, with cadmium screen, layer thickness and geometrical parameters of unit are calculated in such way that at the moment of exposure to radiation mineral temperature does not exceed 200°C, and "Фб.н./Фт.н." ≥10, where "Фб.н." is density of flow of fast neutrons with energy higher than 1MeV, "Фт.н." - density of thermal neutrons flow. Described is device for mineral irradiation, containing hermetical filtering unit, filled with substance or mixture of substances, containing elements, absorbing thermal and resonance neutrons, with axial hole, in which cadmium screen is placed and also placed is a case open from the bottom for partial filling with heat carrier, operation volume of case is filled with minerals, placed in layers between layers of substance or mixture of substances, containing elements, absorbing thermal and resonance neutrons, layers being separated with aluminium interlayer.
Composite tantalate of rare-earth elements / 2438983
Invention relates to novel chemical compounds and can be used in medicine, particularly radiology as an X-ray contrast agent during X-ray examination of various organs. The invention discloses a composite tantalate of rare-earth elements with the formula M1-xM'xTaO4, where 0.01≤x≤0.45; M and M' are elements selected from a group consisting of: yttrium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, as a contrast agent for X-ray diagnosis. The disclosed contrast agent, which provides a high level of X-ray absorption, enables to smoothly and continuously vary the level of absorption with the same quantitative content of the agent owing to change in values of x, i.e., owing to change in the ratio of atoms the first and second elements in the crystal lattice of tantalate.
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FIELD: chemistry. SUBSTANCE: method of forming polydomain ferroelectric monocrystals with a charged domain wall involves using a workpiece in form of plate of ferroelectric monoaxial monocrystal of the lithium niobate and lithium tantalate family, which is cut perpendicular to the polar axis, one of the surfaces of which is irradiated with ion flux to form high concentration of point radiation defects in the surface layer, which results in high electroconductivity of the layer, after which an electric field is formed in the plate, directed along the polar axis, the polarity and value of which enable formation of domains on the surface of the plate which is not exposed, and their growth deep into the plate in the polar direction up to the boundary of the layer with high conductivity, which leads formation of a charged domain wall with an irregular shape, wherein the depth of the layer is determined by the value of the energy and dose of ions, and the shape of the wall is determined by the value of the electric field formed. EFFECT: invention enables to form a charged domain wall, having an irregular three-dimensional shape with given geometric parameters, lying at a given depth in a monocrystalline ferroelectric plate without heating the plate or cutting a workpiece for making the plate. 4 cl, 7 dwg
The invention relates to the field of obtaining single crystals of ferroelectric lithium niobate and lithium tantalate with artificial domain structure and can be used to create devices precise positioning acoustoelectronic devices, devices based on electron emission due to the pyroelectric effect, and also to modify the dielectric and optical properties of crystals. A method of obtaining domain structures when exposed to the crystal temperature gradient in the process of its growth, the so-called layered growth of domain structures (Nofilename, You, Touchline and other Periodic domain structure in the crystal LiNbO3:Y grown by Czochralski method. // Solid state physics, 2000, V. 42 (9, s-1681). The disadvantage of this method is the need of the growing crystal is large in size, relatively small fraction of the crystal volume, suitable for use, for a long time crystal growth and the need for separation of the crystal plates with the required domain structure. The known Method of forming a domain structure in a nonlinear optical plate of the ferroelectric by the electric field (U.S. Patent 5193023, G02F 1/03; G11C 11/22 published 09.03.1993), according to which on the opposite polar surfaces of the plate Faure is irout electrodes, at least one of which is performed according to a certain pattern (configuration) - strip electrode. Then to the electrodes applied voltage, resulting in the formation of the domain structure in accordance with the configuration of the strip electrode. The disadvantage of this method is the impossibility of the creation of charged domain walls in the crystal. The known Method of forming a domain structure in the crystal of a potassium-titanyl-phosphate for nonlinear frequency conversion of laser radiation (RF patent No. 2044337 C1, MPK7 C30B 33/02, C30B 33/04, C30B 33/00, H01L 41/00, C30B 29/30), by forming a domain structure consisting of ferroelectric domains of opposite orientation, with the period determined by the difference of the wave vectors of the primary radiation and the converted frequency. On the crystal surface applied film of material having a coefficient of thermal expansion and conductivity different from the same parameters of the crystal and domain structure is formed either by heating to 850°C and cooling to room temperature or by cooling the crystal potassium titanyl-phosphate below room temperature. Due to the difference of coefficients of thermal expansion between the dielectric and the crystal in the substrate occur tensile and compressive mechanical stress, leading selectbooleancheckbox effect to the appearance of the alternating electric field, having a component directed opposite to the vector of spontaneous polarization of the crystal. Created in this way domain patterns are the surface that does not allow you to create a domain structure with a charged domain wall located at a specified depth. In addition, this method uses the fact that the high conductivity of potassium titanyl-phosphate (103-104times greater than that of lithium niobate), prevents the formation of domains in areas not covered by the film. It is not possible to use this method in materials with low conductivity, such as lithium niobate or tantalate lithium. The closest to this invention is a Method for piezoelectric crystals with a polydomain structure for precise positioning devices (Patent RU 2233354 C1, published 27.07.2004) (prototype), according to which the preparation of the ferroelectric single crystal, which may form only a 180-degree domain walls in which at least two faces parallel to each other and perpendicular to these edges do not coincide with the direction of the axis of spontaneous polarization, moving in thermal field of the zone temperature is above the Curie temperature in an area with a temperature below the Curie temperature with the simultaneous application of periodically varies the dealing alternating the electric field parallel to the faces of the workpiece, after cooling the entire volume of the workpiece below the Curie temperature it formed an ordered domain structure, the sizes of the domains in which you can set the speed of movement of the workpiece and the period of the polarity of the applied electric field thereto, after which divide the blank on the plate, two faces which are parallel to the domain boundary and contain an equal number of domains of opposite polarity. This method allows to form the workpiece with a charged domain boundaries, however, has several disadvantages: the need for separation of the workpiece on the plate after the formation of the domain structure, the necessity of heating the crystal above the Curie temperature, the use of procurement with faces that are not perpendicular to the polar axis of the crystal. In addition, in this way there is no possibility to control the shape of the charged domain walls. The invention achieves the technical result consists in the possibility of creating a charged domain wall, which has a complex three-dimensional shape with a given geometrical parameters, which is located at a predetermined depth in the single crystal plate of ferroelectric lithium niobate or lithium tantalate, there is no need to apply heating plate and cut the workpiece to obtain the plates. The specified technical result is t is achieved as follows. As the workpiece take a plate of uniaxial ferroelectric single crystal of lithium niobate or lithium tantalate, cut perpendicular to the polar axis. One of the surfaces of the plate is exposed to the flow of ions. In the result of the impact of accelerated ions and radiation heating of the crystal structure in the surface layer is broken with the formation of a large concentration of point defects, which increases the conductivity of the layer. Then the plate create an electric field directed along the polar axis of the crystal. The polarity of the field is chosen so that the field was directed opposite to the direction of spontaneous polarization of a ferroelectric. The magnitude of the field is chosen so that began the process of switching polarization representing the formation of domains on the surface of the plates and their germination into the plate. This increased conductivity of the surface layer of the plate leads to a distribution of electric field, the domains grow in depth only to the border of this layer formation near the boundary layer of a charged domain wall complex three-dimensional forms. Geometrical parameters of the wall define the selection parameters of the generated electric field. As the ferroelectric single crystal can the be used for example, lithium niobate; tantalate lithium; lithium niobate doped MgO or tantalate lithium-doped MgO. For the irradiation of the ion flux can be used to install for ion-plasma sputtering, in which is formed a gas flow of ions, and the plate is placed on the sprayed metal target. Can be used, for example, the flow of argon ions with an energy in the range from 1 to 10 Kev. The invention is illustrated as follows. Monocrystalline nonlinear optical ferroelectric lithium niobate or tantalate lithium is a material having a temperature range of spontaneous polarization, the direction of which can be changed by external influences, for example by application of an electric field. Spontaneous polarization in these materials can only take certain directions along one or more polar axes. In particular, lithium niobate and tantalate lithium are uniaxial crystals, thus, have only two possible directions of polarization. Switching of polarization in these materials is due to the formation and growth of domains with opposite polarization direction domains. If the normal to the boundary of the domain (domain wall) is not perpendicular to the direction of spontaneous polarization (about polar and crystal), it is due to a jump of the normal component of the polarization at the border will be an associated charge. The density of the bound charge numerically equal to the change in the normal component of the polarization. In this case, the domain wall is called charged. Charged domain wall has a high electrical conductivity, and optical and photovoltaic properties different from the properties of the material (J. Seidel et al. Conduction at domain walls in oxide multiferroics. // Nature Materials. Nature Publishing Group, 2009. Vol.8, No. 3. P.229-234; M. Gureev, A. Tagantsev, N. Setter Head-to-Head and tail-to-tail 180° domain walls in an isolated ferroelectric // Physical Review B.-2011. Vol.83, No. 18). Charged domain wall can be flat or have a complicated three-dimensional shape, in particular, if it is formed by the application of an external electric field (V.Ya.Shur, E.L.Rumyantsev, E.V.Nikolaeva, E.I.Shishkin. Formation and Evolution of Charged Domain Walls in Congruent Lithium Niobate. Applied Physics Letters, 2000, V.77, N.22, pp.3636-3638). In this invention as the workpiece take a plate of uniaxial ferroelectric single crystal of lithium niobate or lithium tantalate, cut perpendicular to the polar axis. One of the surfaces of the plate is exposed to the flow of ions. In the result of the impact of accelerated ions and radiation heating of the crystal structure in the surface layer is broken with the formation of a large concentration of point defects, which represents a vacancy (for example, oxygen in the kansei) and interstitial atoms, and their complexes. Ion irradiation is accompanied by diffusion of defects. Partially diffusion may be caused by heating of the crystal during irradiation. In addition, a significant role can play interstitial diffusion characteristic of the atoms of small radius, since the interstitial atoms are present in the lattice in irregular positions and to capture vacancies can rapidly diffuse through the interstices. Depending on the dose and energy of the ions due to the formation of defects and their diffusion into the crystal in the surface layer is increased concentration of point defects, which increases the conductivity of the layer, and the thickness of the layer formed by diffusion may greatly exceed the penetration depth of the ions and reach values of a few millimeters. Then the plate create an electric field directed along the polar axis of the crystal. The polarity of the field is chosen so that the field was directed opposite to the direction of spontaneous polarization of a ferroelectric. The magnitude of the field is chosen so that began the process of switching polarization representing the formation of domains on the surface of the plate, and their germination into the plate. To create in the plate of the electric field can be used, nab is emer, metal electrodes or electrodes based liquid electrolyte deposited on the polar surface of the plate, between which the applied voltage. The increased conductivity of the surface layer of the plate leads to a distribution of electric field across the thickness of the plate, the domains grow in depth only to the border of the layer. In the process of growth of domains near the boundary layer is the formation of a charged domain wall complex three-dimensional forms. Geometrical parameters of the form walls depend on the parameters of the layer and the magnitude of the generated electric field. Emerging wall has a complex gear form, characterized by amplitude (the maximum difference of the depths of the points of the wall). In addition, in the cross-section plane that is parallel to the polar axis, the wall has the shape of a zigzag, which may be characterized by the average period. As the ferroelectric single crystal take, for example, lithium niobate or lithium niobate doped MgO, and tantalate lithium or tantalate lithium-doped MgO. These materials are among the most popular for applications in optoelectronics, nonlinear optics and acoustoelectronic due to the large values of electro-optical, nonlinear optical and piezoelectric coefficients. The lithium niobate and chant the lat lithium are isomorphic materials with the same crystal structure and similar physical properties. Importantly, the single crystals of lithium niobate and lithium tantalate high quality are produced industrially in the form of plates with a diameter up to 125 mm MgO Doping significantly increases the threshold of optical damage, which allows, for example, to apply the crystals to convert the wavelength of the radiation in the creation of powerful lasers emitting in the blue-green part of the spectrum. To receive the stream of ions can be used for installation of vacuum ion-plasma sputtering of known construction, in which application of an electric field in a vacuum chamber at a given pressure of gas lighting gas discharge, resulting in the formation of plasma. To the target, which must be irradiated to the flow of ions exert a constant negative voltage relative to the chamber walls, which leads to the extrusion of ions from the plasma and accelerate them towards the target. As a target for sputtering can be used, for example, metal. The plate is placed on the sprayed metal target so that the irradiated side was converted to a plasma discharge. This method of obtaining flow of ions is preferred, as it allows independent control of the ion energy and current density. As gas can be used, for example, argon. It is most often used for p is myshlennyh systems ion-plasma sputtering. The energy of the ions can be in the range from 1 to 10 Kev. In figure 1, 2 and 3 presents the scheme of implementation of the method. Figure 1 - the exposure surface of the wafer 1 by the flow of ions 2 (a cross-section of the plate). Figure 2 - creating the electric field E in the plate with the formed layer 3 having high conductivity, due to the application of the voltage source 4 between the electrodes 5, plotted on a polar surface of the plate, which leads to the appearance of the 6 domains on the unexposed surface of the plate, which grow deep into the plate, fuse to form a charged domain wall 7 near the border layer 3 having high conductivity, as shown in Figure 3. The geometric parameters of a wall: 8 - amplitude, 9 - period. The invention is illustrated by the example of the implementation of the proposed method. As the workpiece monocrystalline ferroelectric take a plate of lithium niobate doped with 5% MgO, with a thickness of 1 mm and a diameter of 76 mm, cut perpendicular to the polar axis and polished on both sides. The plate is placed in the installation of ion-plasma sputtering, depicted in Figure 4. The installation consists of a metal vacuum chamber 10, which creates a gas discharge in argon at a pressure of about 10-4Torr, resulting in a plasma region 11. The metal body of the target 12 is made of copper, placed the plate 1, and the target make a permanent, negative with respect to the vacuum chamber 10 accelerating voltage U, is equal to 2.5 kV. The applied voltage leads to the acceleration of positively charged argon ions from the plasma towards the target, when this occurs, the irradiation of the surface of the plate. The irradiation is carried out when the value of current I of about 4 mA for 5 minutes. When this is achieved the dose up to 1019cm-2. After irradiation of the crystal decreases light transmission in the visible region of the spectrum and the surface conductivity increases to 100 kω/square. The depth of the layer is specified by the value of the energy and dose of the ions and for the value of the accelerating voltage U=2.5 kV is h=150 microns. Then on a polar surface of the plate, put the electrodes in the form of saturated aqueous solution of LiCl, which are widely used in the creation of the electric field in the crystal (E. Soergel Visualization of ferroelectric domains in bulk single crystals // Applied Physics B. 2005. Vol.81, No.6. P.729-751; S. Kwon et al. Domain reversal of periodically poled LiNbO3with a shorter domain inverted period // Thin Solid Films. 2007. Vol.516, No. 2-4. P.183-188). Between the electrodes applied voltage (Figure 2) with the amplitude Us=5 kV during the time interval t=50 C. While the polarity of the voltage is chosen so that the plate was created elektricheskaya E, directed opposite to the direction of spontaneous polarization Ps. As a result of influence of the electric field under the electrode formed domains, the growth of which leads to the formation of charged domain wall complex three-dimensional forms near the boundary layer with high conductivity. Geometrical parameters of the wall the following: amplitude A=80 μm, the period D=6 μm. Figure 5 shows the micrograph obtained with a polarizing microscope in the formation of charged domain walls. The observed optical contrast associated with electro-optical effects caused by the presence of an electric field created related charges on a charged domain wall. In addition, the domain structure was observed using known techniques of optical microscopy after the well-known method of selective chemical etching plate with concentrated hydrofluoric acid (HF) for 5 minutes, and is also known by scanning laser confocal microscopy Raman scattering. The image of the cross section of the plate created with charged domain wall 7, obtained using optical microscopy after selective chemical etching, is shown in Fig.6. The shape of the wall is determined by the magnitude of the generated electric field. In an hour the particular figure 7 shows the micrograph obtained with a polarizing microscope in the formation of charged domain walls in the growth of domains with application of an electric voltage of lesser magnitude (Us=1 kV). The shape of the charged domain wall is qualitatively different from the one shown on Figure 5: structure more isotropic, and the straight wall is much shorter. This feature is due to the fact that the formation of a charged domain wall starts with a larger number of centres. Thus, the proposed method allows to form in ferroelectric single crystals of lithium niobate or tantalate lithium charged domain wall, which is located at a predetermined depth in the crystal. 1. The method of formation of polydomain ferroelectric single crystals with charged domain wall, characterized in that as the blanks using the plate uniaxial ferroelectric single crystal family of lithium niobate and lithium tantalate, cut perpendicular to the polar axis, one surface of which is exposed to the flow of ions for forming the high concentration of point radiation defects in the surface layer, which increases the conductivity of the layer, after which the plate creates an electric field is directional along the polar axis, the polarity and magnitude of which provide the formation of domains on the surface of the plate is not subjected to irradiation, and their germination into the plate in the polar direction to the boundary layer with high conductivity, which leads to the formation of a charged domain wall complex shape, and the depth of the layer is specified by the value of the energy and dose of ions, and the shape of the wall is determined by the magnitude of the generated electric field. 2. The method according to claim 1, in which the ferroelectric single crystal using the lithium niobate doped MgO, or tantalate lithium-doped MgO. 3. The method according to claim 1, in which exposure to the flow of ions use the facility for ion-plasma sputtering, and the plate is placed on the sprayed metal target. 4. The method according to claim 1, in which use the flow of argon ions with energies from 1 to 10 Kev.
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