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Invention relates to PCD diamond to be used in production of water-jet ejectors, engraving cutters for intaglio, scribers, diamond cutters and scribing rollers. PCD diamond is produced by conversion and sintering of carbon material of graphite-like laminar structure at superhigh pressure of up to 12-25 GPa and 1800-2600°C without addition of sintering additive of catalyst. Note here that sintered diamond grains that make this PCD diamond feature size over 50 nm and less than 2500 nm and purity of 99% or higher. Diamond features grain diameter D90 making (grain mean size plus grain mean size × 0.9) or less and hardness of 100 GPa or higher. |
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Method for preparing nanodiamonds with methane pyrolysis in electric field Invention may be used in medicine in producing preparations for a postoperative supporting therapy. What is involved is the high-temperature decomposition of methane on silicone or nickel substrate under pressure of 10-30 tor and a temperature of 1050-1150°C. The heating is conducted by passing the electric current through a carbon foil, cloth, felt or a structural graphite plate whereon the substrates are arranged. An analogous plate whereon a displacement potential from an external source is sent is placed above the specified plate. Nanodiamonds of 4 nm to 10 nm in size are deposited on the substrates. |
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Plunger pair and metering pump comprises at least one external part of crystal based on aluminium oxide alpha-modification and at least one internal part of crystal based on aluminium oxide alpha-modification, preferably, leucosapphire with working surface roughness Ra2÷5Å. Said surface smoothness is brought about by processing the cylindrical surfaces of part of crystal based on aluminium oxide alpha-modification. This method comprises drilling the preliminary blanks of part of crystal based on aluminium oxide alpha-modification with the help of diamond tool. Three-stage mechanical processing is performed by diamond tool with lubricant-coolants and sequential decreased in abrasive grain size to 125/100 and/or 100/80 mcm. Internal strain is removed from blanks by annealing at muffle furnace. Surface is processed by semisoft or soft grinding wheel or by lap with diamond 5/3 mcm or 1/0 mcm grain on clock oil. Tribochemical finishing of the surface is performed by colloidal SiO2-based composition. |
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Method of obtaining silicon carbide layers Silicon carbide is obtained by displacement of a carbon foil tape in a horizontal plane with supply to its surface of melted silicon, the process being performed in dynamic vacuum, rate of displacement being specified within the range of 0.5-3.0 m/min, which results in formation of microcrystals of semiconductor silicon carbide of a cubical structure in the form of a self-bound layer. The said crystals are bound with thin interlayers of excessive silicon, supplied from a feeder. After extraction of the tape with the grown layer, it is cut into measured strips, which are placed in furnaces and heated in air to a temperature of 1050°C for 8 hours. |
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Method and device for sapphire monocrystal growth Invention relates to production of sapphire monocrystals used for production of blue or white LEDs. This device comprises kiln 10 for heating to temperature above sapphire debris fusion and insulating from ambient air. Crucible 20 is arranged in sais kiln to fuse sapphire debris therein and to allow monocrystal growth from seed crystal 51 in crucible 20. Heater 30 is arranged outside said crucible 20 to fuse sapphire debris. Coolers 40 are arranged at crucible 20 bottom to prevent a complete fusion of seed crystal 51. Note here that heaters 30 is composed by several separate heaters controlled independently by temperature gages, power controllers and temperature control units so that uniform temperature inside crucible in horizontal direction is maintained. Said heater 30 can comprises several lateral heaters 32 arranged on both sides of crucible 20, nearby its outer walls, each being connected with appropriate electrode 31.Besides, it comprises connection heater 33 arranged at top parts of heaters 32 to interconnected lateral heaters so that vertical temperature gradient is created and quantity of electrode is decreased. |
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Method of growing monocrystals of lithium-bismuth molybdate Invention relates to field of chemical technology and deals with obtaining volumetric crystals with composition Li8Bi2(MoO4)7. Crystals are grown from solution-melt of lithium-bismuth molybdate in solvent by crystallisation with gradual cooling of melt and grown crystals, and as solvent used is eutectic mixture, containing 47 mol.% of molybdenum oxide and 53 mol.% of lithium molybdate with content of lithium-bismuth molybdate and eutectic mixture equal 10-40 mol.% and 90-60 mol.% respectively, growing is performed under conditions of low temperature gradients, constituting less than 1 grad/cm, on primer, oriented by [001] and rotating at rate 20-30 rev/min with pulling rate 0.5-2.0 mm/day with constant cooling of solution-melt at rate 0.2-5.0 degree/day with further separation of grown crystals from solution-melt and cooling them to room temperature. |
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Monocrystal growing by crucibleless zone melting and device to this end Proposed method comprises crystal seeding from fused zone, curing for preset time and drawing the monocrystal for seeding from fused zone at temperature gradient. Here, fused zone central symmetric part diameter is controlled. Note also that crystallisation front diameter is selected with preset correction to allow for tolerable deviation of grown monocrystal diameter from preset magnitude. Said magnitude is kept constant during the entire growing process by adjusting the said fused zone central symmetric part diameter owing, in particular, to variation of growth chamber top rod displacement rod. This method is implemented with the help of device including growth chamber 3 with top and bottom rods, video camera 1 fitted in port 2 of growth chamber 3. Video camera output is connected via signal processing unit 4 to control signal generator 5 with its output connected with rod displacement rate ACS input 6, ACS being connected to rod displacement drive 7. Besides it comprises stroboscope 8 arranged ahead of port 2 of growth chamber 3 and synchroniser 9 connected with inputs of stroboscope 8 synchronisation and video camera 1. Signal processing unit 4 comprises processor 10 with image frame isolation module 11, image outline isolation module 12, fused zone central symmetric part diameter calculation module 13 and crystallisation front diameter calculation module 14. Note here that processor 10 is connected with synchroniser 9. Output of video camera 1 is connected to image frame isolation module 11 connected via image outline isolation module 12 to inputs of crystallisation front diameter calculation module 14 and fused zone central symmetric part diameter calculation module 13. Outputs of the latter are connected to first and second averaging filters 15, 16. Control signal generator 5 is composed by two-stage proportional-integration-differentiation controller. Note here that inputs of controller first stage 17 allowing for actual monocrystal crystallisation front are connected with output of the first averaging filter 15 and correction setting module 18. Inputs of the controller second stage 19 allowing for actual monocrystal crystallisation front are connected with controller first stage 17 output and output of second averaging filter 16. Controller second stage 19 output is connected to ACS input. |
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Single crystal diamond material Invention relates to technology of obtaining single crystal diamond material for electronics and jewellery production. Method includes growing single crystal diamond material by method of chemical precipitation from vapour or gas phase (CVD) on main surface (001) of diamond substrate, which is limited by at least one rib <100>, length of said at least one rib <100> exceeds the longest surface dimension, which is orthogonal to said at least one rib <100>, in ratio at least 1.3:1, and single crystal diamond material grows both on the normal to the main surface (001) and sideward from it, and during CVD process value α constitutes from 1.4 to 2.6, where α=(√3×growth rate in <001>) ÷ growth rate in <111>. |
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Method of exfoliation of layered crystalline materials Method includes exfoliation of blanks from layered crystalline materials, fixed on one side on gliphtale support, with application of adhesive tape, when exfoliation is completed, gliphtale is dissolved in acetone, where suspension of crystalline plates (layers) of metal chalcogenides is formed, the latter are separated from suspension by their precipitation on substrate. |
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Atomic layer deposition apparatus and method of loading atomic layer deposition apparatus Invention relates to an atomic layer deposition apparatus and a method of loading said apparatus. The apparatus comprises ALD reactors, each configured to receive a batch of substrates for ALD treatment and includes a reaction chamber with top loading, a system of covers, a hoisting device for hoisting the system of covers for loading the reaction chamber and a loading robot. The loading robot has a gripping part and a movement device, wherein the loading robot is configured to perform multiple loading operations for loading each of the ALD reactors. Each loading operation includes gripping the gripping part in a zone or on a storage shelf of a substrate holder in the batch of substrates, the movement device moving the substrate holder with the batch of substrates into the reaction chamber of the corresponding ALD reactor and lowering said substrate holder vertically from the top into the corresponding reaction chamber. |
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Method to produce diamond-like coatings by combined laser action Diamond-like coatings are produced in vacuum by spraying of target material with an impulse laser. The target material made of graphite of high degree of purity (more than 99.9%) is exposed to combined laser radiation: first short-wave (less than 300 nm) pulse radiation, the source of which is a KrF-laser with wavelength of 248 nm and specific energy of 5·107 W/cm2, as a result of which ablation is carried out, and gas-plasma phase of target material is generated. Subsequent exposure of a gas-plasma cloud during cloud flight from a target to a substrate is carried out by long-wave (more than 1 mcm) laser radiation. The source of long-wave laser radiation is a gas CO2-laser or a solid-state fibrous laser radiator. |
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Invention relates to technology of production of synthetic diamond material, which can be applied in electronic devices. Diamond material contains single substituting nitrogen ( N s 0 ) in concentration more than 0.5 ppm and having such complete integral absorption in visible area from 350 nm to 750 nm, that at least nearly 35% of absorption is attributed to N s 0 . Diamond material is obtained by chemical deposition from vapour or gas phase (CVD) on substrate in synthesis medium, which contains nitrogen in atomic concentration from nearly 0.4 ppm to nearly 50 ppm, and gas-source contains: atomic part of hydrogen, Hf from nearly 0.40 to nearly 0.75, atom part of carbon, Cf, from nearly 0.15 to nearly 0.30; atomic part of oxygen, Of, from nearly -.13 to nearly 0.40; and Hf+Cf+Of=1; ratio of atomic part of carbon to atomic part of oxygen, Cf:Of, satisfy the ratio nearly 0.45:1<Cf:Of< nearly 1.25:1; and gas-source contains atoms of hydrogen, added in form of hydrogen molecules, H2, with atomic part of the total quantity of present atoms of hydrogen, oxygen and carbon between 0.05 and 0.40; and atomic parts of Hf, Cf and Of represent parts from the total quantity of atoms of hydrogen, oxygen and carbon, present in gas-source. |
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Method of obtaining optic polycrystalline materials based on zinc selenide Method includes preparation of charge based on zinc selenide, its placing into reactor, vacuumisation to pressure 10-5-10-4 mm Hg, heating reactor evaporation zone to the temperature of evaporation, passing ZnSe vapour through filter with its following sedimentation on substrate which has the temperature lower than the evaporation temperature, and following cooling of reactor with half-finished product to room temperature; as charge applied is mixture of zinc selenide with elementary selenium with the following wt %: zinc selenide - 90-99, elementary selenium - 1-10, reactor evaporation zone is heated to the evaporation temperature of 1000-1200°C, cooling is carried out at rate 25-30°C/h. |
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Invention relates to technology of obtaining pure substances, which are applied in field of high technologies: semi-conductor, solar energy, fiber-optic communication. Method of obtaining polycrystalline silicon is realised by plasmochemical pyrolysis of initial quartz raw material particles in flow reactor in flow of plasma of inert gas - argon and hydrogen, and as initial quartz raw material applied is natural quartz concentrate with size of particles not larger than 20 mcm, pyrolysis is realised at temperature 6500-13000 K with decomposition of reacting mixture into silicon and oxygen atoms, after which gas phase atomic mixture is cooled in the interval from 6500 to 2000 K at rate 105-106 K/s to form silicon vapour due to binding of free oxygen with hydrogen without silicon re-oxidation, after which obtained silicon vapour is condensed by further cooling of mixture to 1000 K with formation of polycrystalline silicon in form of spherical particles. |
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Method of producing solid semiconductors with addition of doping admixtures in crystallisation Invention relates to production of solid semiconductors, particularly, to silicon as ingots or strips used for fabrication of photovoltaic element substrates. Proposed method comprises the stages of semiconductor melt preparation from the semiconductor first portion including doping admixtures and solidification of fused semiconductor. Additionally, it comprises addition in one or several steps during solidification of extra semiconductor portions also containing doping admixtures to semiconductor melt. |
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Device for liquid phase epitaxy of multilayer semiconductor structures Device contains a body 1 with a cover 2, a container 3 with source melts reservoirs equipped with pistons 4, a multi-sectional holder 14 of substrates, a growth station 5 and channels for melts delivery and output. The container 3 with reservoirs is located under the multi-sectional holder 14 of substrates. The cover 2 is equipped with protrusions to output excess of melts. The device contains additional reservoirs 7 for a part of used melts which are installed over the container 3; each reservoir is equipped with a cover 8 with load and a port for melt discharge to the main container 3 located beneath. |
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Method and apparatus for neutron doping of substance Method for neutron doping of a substance involves slowing down fast source neutrons with a retarder substance, forming a stream of slow neutrons in a selected region and irradiating the substance to be doped with the slow neutrons. During the slowing down process, the fast source neutrons are separated according to propagation angles thereof; streams thereof moving a direction selected by the structure of the retarder substance are selected; streams selected by the structure are summed up, formed into a narrow band and directed onto the substance to be doped, which is controllably moved in the focal region of the neutron streams. |
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Device and method for growing profiled crystals of high-melting compounds Device includes melting pot 2 with molten metal 3, which is arranged in growth chamber 1 connected to an inert gas supply device, and stock 9 with seeding agent 10, which is installed above shaper 4 with annular feed capillary 5 made in it and at least one vertical channel 6 located in upper part of shaper 4; melting pot 2 is installed so that it can move vertically; in upper part of shaper 4 parallel to an end surface there is through channel 7 connected to each vertical channel 6 of shaper 4; with that, diameter of through channel 7 is at least 2.5 diameters of vertical channel 6; and in lower part of shaper 4 there is buffer cavity 8 open for melt 3 and connected to feed capillary 5. |
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Growth method of paratellurite crystals of polygonal shape, and device for its implementation Growth method of paratellurite crystals of a polygonal shape from a melt involves build-up of tellurium dioxide powder into a platinum melting pot; creation of the required axial temperature distribution, which is provided by a temperature gradient of 1-2 degrees/cm above the melt, with a step of 2-3 degrees at an air-melt boundary line, by temperature increase by 2-3 degrees to the depth of 2 cm and temperature constancy throughout the rest melt thickness; determination of equilibrium temperature when an inoculating crystal touches the melt surface; growth of the crystal at its rotation and drawing with the specified change of the cross-sectional area using a weight automatic control system and a heating surface with four independent heating elements in a vertical direction, separation of the crystal from the melt and cooling of the crystal till room temperature; with that, a furnace is used, in which middle heating elements are made in the form of three equal segments of 120 degrees each, and growth of the crystal is performed under conditions of non-homogeneous radial warm-up of the melt by temperature increase by 1-2 degrees in a 120-degree sector in the lower part of the growth melting pot. |
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Method of producing silicon filaments with arbitrary cross-section (versions) One of the versions of producing silicon filaments in form of rods and/or substrates with an arbitrary cross-section from high-purity silicon involves continuous fusion casting of silicon downwards on a seeding agent through a draw plate situated between the melt zone and an inductor in an atmosphere of oxygen, cooling the obtained filament by immersion in a coolant, wherein seeding is carried out below the plane of the draw plate; the level of the coolant is set and kept near the crystallisation front, and the crystallisation front of silicon rods and/or substrates is held below the plane of the draw plate at a distance of 0.5-20 mm. |
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Method of forming monocrystalline films of solid bismuth-antimony solution on substrates Monocrystalline films of a solid bismuth-antimony solution are obtained using zonal recrystallisation of vacuum sputtered, uniform-composition polycrystalline films of a solid bismuth-antimony solution under a protective coating, the melting point of which is higher than that of the obtained film, at a higher rate of zone movement than when growing bulk monocrystals (for films of solid bismuth-antimony solutions higher than 1 cm/h versus 0.05 mm/h for bulk crystals). |
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Thallium bromide based crystals for ionising radiation detectors Invention relates to production of materials for ionising radiation detectors which can be used for infrared optics, laser engineering and acoustooptics. The thallium bromide-based crystal further contains calcium bromide, with the following ratio of components, wt %: thallium bromide - 99.9972-99.99993, calcium bromide - 0.0028-0.00007 wt %. |
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Method of producing yttrium aluminium garnet alloyed with rare earth elements Proposed method consists in precipitation at introduction of starting compounds of aluminium, yttrium and alloying agents in arrester to extract precipitated product and to calcine obtained powder at 1100°C. Note here that precipitation is performed in the presence of fluorine-bearing additive taken in amount corresponding to 1-5% content of fluorine atoms relative to amount of arrester. Arrester represents ammonium bicarbonate. Mixed aqueous solution of aluminium, yttrium and alloying element nitrates are added to said bicarbonate in amount corresponding to molar ratio of ammonium bicarbonate to total amount of metal cations equal to 3.6:1. Thereafter, obtained mix is mixed at the rate of 300-500 rpm to flush precipitated product, to dry is at 100-150°C and to calcine it. |
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Method and device for deposition reactors Precursor vapours 101 are fed through reaction chamber cover in feed line 141, 142 into deposition reactor reaction chamber 110. Vertical flow of precursor vapours is set and forced vertically from top to bottom in spacing between vertical substrates 170. Material is deposited on surfaces of substrates 170 mounted vertically. |
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Method of growing yag doped with vanadium Method of growing YAG doped with vanadium consists in crystal growing by vertically directed crystallisation in molybdenum crucible in reduction atmosphere of argon with hydrogen and using charge that ensures vanadium content on grown crystal varying from 1 to 5 atom percent. Note here that batch composition is defined by general formula Y3Al5(1-0.01x)V0.05xO12, where x is atom percent in octahedral and tetrahedral positions of crystal lattice. |
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Producing method of nanocrystalline silicon-replaced hydroxyapatite Producing method of monophasic nanocrystalline silicon-replaced hydroxyapatite involves synthesis of silicon-containing hydroxyapatite by means of a method for deposition from water solution of reagents containing orthophosphoric acid, calcium hydroxide and tetraethyl orthosilicate at pH of not less than 9 and molar ratio of Ca/P in the range of 2.0 to 2.5; sedimentation for completion of a phase formation process, extraction of deposit, drying and heat treatment of deposit; with that, synthesis is performed by adding 10-20% solution of orthophosphoric acid at the speed of 0.2-0.8 ml/min per litre of water solution of calcium hydroxide / tetraethyl orthosilicate composition prepared by means of 0.08-0.16% water solution of calcium hydroxide and design amount of tetraethyl orthosilicate to obtain a finished product with silicon replacement degree x equal to 1-2 and molar ratio of Ca/(P+Si), which is close to 1.67, and heat treatment is performed at the temperature of not lower than 300°C, but not higher than 400°C. Invention allows obtaining stoichiometric monophasic product of phases with average size of crystals of 9.95-12.53 nm, specific surface of 108.97-132.58 m2/g, and increased bioactivity, at the heating of which incidental phases do not occur. |
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Heterostructures sic/si and diamond/sic/si, and also methods of their synthesis Heteroepitaxial semiconductor film on a single-crystal silicon substrate is grown by the method of chemical deposition from the gas phase. Synthesis of the heterostructure SiC/Si is carried out on a single-crystal silicon substrate in a horizontal reactor with hot walls by means of formation of a transition layer between the substrate and the film of the silicon carbide with the speed of not more than 100 nm/hour with heating of the specified substrate to the temperature from 700 to 1050°C with application of a gas mixture containing 95-99% of hydrogen and the following sources of silicon and carbon SiH4, C2H6, C3H8, (CH3)3SiCl, (CH3)2SiCl2, at the same time C/Si≥2, and formation of the single-crystal film of silicon carbide with the help of supplu of steam and gas mixture of hydrogen and CH3SiCl3 into the reactor while maintaining absolute pressure in the reactor in the range from 50 to 100 mm of mercury column. The silicon substrate is a plate that has an angle of inclination of crystallographic direction (111) in direction (110) from 1 to 30 of angular degrees and in direction (101) from 1 to 30 angular degrees. |
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Method for making fancifully coloured orange monocrystalline cvd-diamond, and finished product Monocrystalline diamond material that has been grown using a CVD method and has concentration of single substituent nitrogen [Ns 0] of less than 5 ppm is irradiated to introduce isolated vacancies V to at least some part of the provided CVD-diamond material so that total concentration of isolated vacancies [VT] in the obtained diamond material is at least more than (a) 0.5 ppm and (b) by 50% more than concentration [Ns 0] in ppm in the provided diamond material; after that, annealing of the obtained diamond material is performed so that chains of vacancies can be formed from at least some of the introduced isolated vacancies at the temperature of at least 700°C and maximum 900°C during the period of at least 2 hours; with that, irradiation and annealing stages reduce the concentration of isolated vacancies in diamond material, due to which concentration of isolated vacancies in the irradiated and annealed diamond material is <0.3 ppm. |
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Method of sulphide compound crystal growth based on rare-earth element sesquialteral sulphides Invention relates to production of sulphide compound crystals based on sesquialteral sulphides of rare-earth metals doped with tin, including in the form of high-temperature polymorphous γ-modification. Proposed method comprises loading of initial components into heat-resistant crucible, placing the latter into quartz reactor, degassing and sealing of said reactor and heating the latter in oven. Said initial components represent the mix of sesquialteral sulphide of rare-earth element, REE=Y, La-Lu, and tin sulphide, or mix of powders of sesquialteral sulphide of rare-earth element and tin sulphide, or mix of elementary lanthanide, tin and sulfur taken in stoichiometric ratio for synthesis of Ln2S3 and SnS. Reactor is heated to above tin sulphide fusion point, tin sulphide being used as a solvent, and kept at said temperature unless melt-solution homogenising. Then, temperature gradient is developed over the reactor length for solvent mass transfer from said melt-solution into colder part of said reactor, evaporation of solvent and crystallisation from melt-solution with doping of crystals by tin cation. |
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Unit and method for obtaining polycrystalline silicon Method is implemented in a reactor containing a bottom plate forming a lower part of the reactor and a bell-shaped vacuum cap attached to the bottom plate so that it can be removed, in which on the bottom plate there located is a variety of gas inlet holes for supply of raw gas in upward direction to the reactor, and gas outlet holes for discharge of waste gas after the reaction, and in which the variety of gas inlet holes is located concentrically along the whole surface area enveloping the upper surface of the bottom plate, in which many silicon target rods are installed; at that, silicon target rods are heated and polycrystalline silicon is deposited from raw gas on surfaces of silicon target rods. Supply of raw gas from gas inlet holes is stopped near the reactor centre during the specified period of time while raw gas is being supplied form other gas inlet holes at early stage of the reaction, and a way for descending gas flow is provided after it collides with vacuum cap ceiling. |
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Method for obtaining monolithic crystals of silicon carbide involves the following: i) placing of mixture containing chips of polycrystalline silicon and carbon powder onto the bottom of a cylindrical reaction chamber having a cover plate; ii) sealing of cylindrical reaction chamber; iii) placing of cylindrical reaction chamber into a vacuum furnace; iv) pumping of air out of the furnace; v) filling of the furnace with mixture of gases that are essentially inert gases to approximately atmospheric pressure; vi) heating of cylindrical reaction chamber in the furnace to the temperature of 1975 to 2500°C; vii) pressure drop in cylindrical reaction chamber to less than 50 torr, but not less than 0.05 torr; and viii) implementation of sublimation and condensation of vapours on inner part of the cover plate of cylindrical reaction chamber. |
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Scintillator for detecting neutrons and neutron detector Scintillator for detecting neutrons has a metal fluoride crystal selected from LiCaAlF6, LiSrAlF6, LiYF4, which serves as a matrix in which content of 6Li atoms per unit volume (atom/nm3) ranges from 1.1 to 20. The crystal has effective atomic number from 10 to 40, and contains at least one type of lanthanide selected from a group consisting of cerium, praseodymium and europium. The neutron detector contains said scintillator and a photodetector. The metal fluoride crystal is obtained by melting a mixture composed of lithium fluoride, a fluoride of said metal, having valence of 2 or higher, and lanthanide fluoride and a monocrystal is grown from the melt. |
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Method of crystal growth by kiropulos method Proposed method of crystal growth from the melt or solution-melt comprises crystal growth at starting bar locked at crystal holder at melt surface top point, growing the crystal in growth crucible at slow temperature decrease and cooling the grown crystal. Note here that, after growth cycle, melt or solution-melt remained in crucible is drained via pipe heated by extra heater arranged at crucible bottom while grown crystal is cooled in crucible without melt. Lithium triborate crystal sized to 150×130×80 mm is thus produced with optically qualitative part makes 80-90-volume of grown crystal. |
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Method of growing germanium monocrystals Germanium monocrystals are grown in crystallographic direction [111] after holding at melting point for 1-2 hours, with temperature gradient at the crystallisation front in the range of (10.0÷18.0) K/cm, which provides dislocation density on the level of (2·104-5·105) per cm2. |
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Method for formation of bidomain structure in single-crystal plates Electrodes in the form of a system of parallel strings are applied onto two flat-parallel faces of the crystal, which are aligned at the angle of z+36° to the polar axis, wire platinum contracts are connected to electrodes, the assembled cell is placed into a furnace and heated to temperature of phase transition - Curie temperature under action of a heterogeneous electric field, as a result of which two oppositely charged domains of equal volume are formed with a flat domain-to-domain border. |
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Method of diamond selective grinding Invention relates to diamond grinding in making diamond rock cutting tool. Proposed method comprises processing the diamonds in velocity layer of magnetic fields together with ferromagnetic particles. Mix composed of ferromagnetic particles and diamond grains fills the cylindrical case by 0.25-0.35 of its volume. Diamond magnetic susceptibility is defined by the relationship: X 1 ≥ g R 1 ( R 1 + R 2 ) 2 24 μ 0 ρ 2 R 2 2 H 2 X 2 , where X1, X2 are diamond and ferromagnetic particle magnetic susceptibility, m3/kg; g is acceleration of gravity, m/s2; R1, R2 are diamond and ferromagnetic particle grain radii, m; µ0 is magnetic permeability of vacuum, (µ0=4π·107 GN/m); ρ2 is ferromagnetic particle density, kg/m3; H is magnetic field intensity, A/m. Note here that the relationship between diamond grain weight and that of ferromagnetic particles makes 0.51-0.61. |
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Method of growing profiled monocrystals of germanium from liquor Profiled monocrystals of germanium are grown on seed crystal from liquor with application of shape-former, placed in crucible and having holes in the place where its lower part adjoins crucible bottom for removal of excessive liquor; first initial charge of germanium is placed into shape-former and space between crucible wall and shape-former and melted, with height of liquor in said space being at the level 0.85÷0.95 of height of liquor in shape-former, after that, seed crystal rotating with angular speed in the range 5÷20 rev/min is placed into liquor of shape-former, and crystal is grown in radial direction until its diameter approaches diameter of shape-former, then rotation of crystal is stopped, regulated reduction of temperature to complete crystallisation of entire liquor volume in shape-former with formation of its excess and flowing of liquor through holes of shape-former into space between crucible and shape-former is carried out, after which entire volume of liquor in space between crucible and shape-former is crystallised by further reduction of temperature. |
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Method of producing polycrystalline optical zinc selenide Method involves heating and evaporating starting material at temperature of 1050-1150°C, condensing vapour on a substrate heated to 950-1050°C at a rate of 0.2-0.8 mm/h, wherein cooling the apparatus with the grown workpiece is carried out in a controlled manner, where at below 900°C cooling is carried out at a rate of 50-100°C/h, in the range of 900-600°C - at a rate of 30-50°C/h and at above 600°C - inertial cooling to room temperature. To evaporate semi-volatile impurities, the starting material in form of powder or compact chips can be subjected to preliminary annealing in a medium of an inert gas, e.g. argon, at temperature of up to 1200°C for 10-15 hours. The invention enables to obtain the following optical properties with diameter of the grown workpieces of up to 500 mm and thickness of up to 50 mm: transmission at wavelength of 0.6 mcm - 30%, 1.06 mcm - 60%, 3-5 mcm 69%, 8-12.5 mcm - 71%. Birefringence in the optical material does not exceed 100 nm/cm. |
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Method of producing nanocrystalline silicon-substituted hydroxylapatite Method involves mixing phosphates, calcium and silicon compounds, milling and mechanochemical synthesis, wherein the starting components used are disubstituted anhydrous calcium phosphate, annealed calcium oxide and amorphous hydrated silicon oxide with water content of less than 0.5 mol, with specific surface area of 200-450 m2/g in amount of not more than 1.2 mol silicon per elementary cell of hydroxylapatite; mechanochemical solid-phase synthesis is carried out in high-energy planetary mills with drum rotation speed of 1200-1800 rpm for 12-30 minutes. Calcium oxide is annealed preferably at temperature of 900°C for 5 hours. |
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Substrate for growing epitaxial layers of gallium arsenide Invention involves use of substrates made from intermetallic compounds to grow epitaxial layers of GaAs, said compounds having a strict stoichiometric composition, and specifically from gallium lanthanides GaLa3 and Ga3La5, gallium zirconides Ga3Zr and Ga3Zr5, aluminium zirconide Al3Zr, aluminium ceride CeAl2, palladium beryllide BePd, magnesium lanthanide MgLa, aluminium lanthanide Al2La, platinum stannide Pt3Sn, indium lanthanide InLa, tin zirconide SnZr4, platinum plumbide Pt3Pb. |
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Method of making composite polycrystalline and monocrystalline diamond plate Method of making monocrystalline and polycrystalline diamond plates with a large surface area involves arranging, without touching each other, workpiece monocrystals with surface orientation (100) on a substrate holder, creating nucleation centres on the surface of the substrate holder free from the workpiece monocrystals, simultaneous chemical vapour deposition (CVD) of an epitaxial layer on the surface of workpiece monocrystals and a polycrystalline diamond film on the remaining surface of the substrate holder. As a result of chemical vapour deposition of the diamond, splicing of monocrystalline and polycrystalline diamond takes place on the side surface of the workpiece monocrystals to form a diamond plate of a large surface area, having spliced monocrystalline and polycrystalline diamonds. To obtain a plane-parallel CVD diamond plate, the grown composite diamond substrate is polished on both sides. |
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Method for obtaining columnar monocrystals of silicon from sand, and device for its implementation Method involves preliminary installation in lower part of a melting pot of fuse providing crystallisation of end product, charging of the cavity of the melting pot with raw material consisting of sand grains so that there provided is continuous supply to the cavity of the melting pot of new additional portions of raw materials from the volume of the additional tank, which is interconnected with it and isolation of the melting pot cavity with monocrystal being formed in it from outside environment, and treatment of raw material with artificially created physical field at constant rotation of the melting pot with the crystal being formed in its cavity about its longitudinal axis, at the pressure, the value of which does not correspond to the value of atmospheric one. Besides, silicon oxide particles are used as initial raw material, which are obtained by crushing of sand grains to the size of 1-8 mcm, which are contained in the air suspension formed in the melting pot cavity in the volume of 40-60%, and as artificially created physical field - rotating alternating magnetic field, the intensity of which in conversion zone of initial raw material is 1×105÷1×107 A/m, and frequency is 40-70 Hz, treatment of raw material is performed in the melting pot consisting of three independent parts: upper detachable part being a raw material tank; a serviceable melting pot that is immediately intended for growth of monocrystals, the cavity of which is interconnected with the tank volume; and lower detachable part attached to lower part of the serviceable melting pot, which is intended for collection of wastes formed in it during treatment, and namely slags and granules of silicon, which is interconnected with its inner volume through calibrated orifices made in a detachable partition wall. Besides, to the cavity of the serviceable melting pot there constantly supplied are compressed air jets under excess pressure of 0.1-0.6 kgf/cm2, and rotation of the melting pot is performed during 54-72 minutes at two stages, at the first one of which the rotation axis constantly keeps vertical orientation; and at the second stage the above axis changes its initial position from time to time by being diverted from it through the earlier specified angle of 5-15°. The melting pot performs the function of a closing connecting link for the system generating alternating magnetic fields. |
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Method of growing lithium-magnesium molybdate monocrystals Invention relates to the technology of growing lithium-magnesium molybdate Li2Mg2(MoO4)3 crystals. The method involves melting lithium-magnesium molybdate in a molten solvent, crystallising while cooling the melt and cooling the grown crystals, wherein the solvent used is lithium molybdate Li2MoO4 with molar ratio of lithium-magnesium molybdate to lithium molybdate Li2MoO4 of 2:3, respectively; crystallisation is carried out on an inoculating crystal revolving at a rate of 35 rpm, oriented on the [010] direction, rate of drawing rate of the inoculating crystal of 1-3 mm/day while simultaneously cooling the melt at a rate of 0.2-5 degrees/day and then separating the grown crystals from the melt and cooling at a rate of 30 degrees/hour. |
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Method of growing crystals of silver and thallium halides Invention relates to production of materials which are transparent in the infrared region, and specifically crystals of silver and thallium halides, which can be used in making optical components transparent in the wavelength range from 0.4 mcm to 25 mcm, as well as in making infrared fibre light-emitting diodes. The method of growing crystals of silver and thallium halides involves loading material based on a solid solution of silver or thallium halides into a container made from heat-resistant glass, melting, filtering the melt through an opening in the container into a receiving ampoule and directed crystallisation of the melt by moving in a temperature gradient. Before filtering, the melt is cooled to a temperature which is 1-2 degrees lower than the melting point of the corresponding solid halide solution, held for 1.5-2.0 hours, followed by overheating the melt 40-50 degrees higher than the melting point of the solid solution, and filtering is carried out at a rate of 0.1-2.0 l/min. |
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Method of making crystalline workpieces of solid solutions of silver halides for optical components Method involves loading starting separate silver chloride and silver bromide salts into a container made of heat-resistant glass, fusing said salts to a given composition of solid solution, growing a monocrystal in a halogenating atmosphere by moving the container in a temperature gradient, cooling the grown crystal to room temperature and removing the crystal from the container; the monocrystal is then heated at a rate of 50-60°C per hour to temperature of 250-270°C, held at said temperature for 1-2 hours, cooled at a rate of 20-25°C per hour to temperature of 100-150°C and then cooled at a rate of 30-40°C per hour to room temperature. |
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Crystalline antibodies against htnfα Method of batch crystallisation is provided for crystallising the antibody against hTNFα, comprising combining an aqueous solution of the antibody, salt of inorganic phosphate and acetate buffer, and incubating the resulting mixture. The crystalline antibody is considered, in particular the antibody D2E7 obtained by the method according to the invention, the pharmaceutical compositions including injectable liquid compositions comprising the antibody crystal, the crystal suspension, and also the methods of treatment the hTNFα-related disorder connected with, and application of the antibody crystals for obtaining the pharmaceutical composition for treatment such diseases. |
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Method of forming polydomain ferroelectric monocrystals with charged domain wall 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. |
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Nitride monocrystal, method for production thereof and substrate used therein Method of producing a nitride monocrystal by epitaxial growth on a base (100), having a growth plane (105), comprises steps of: forming a sacrificial layer (101) on the base (100), forming columns (102) on said sacrificial layer, growing a nitride crystal (103) layer on the columns at such growth conditions that said nitride crystal layer does not pass downwards to the base in depressions (107) formed between the columns, removing the nitride crystal layer from the base. Said columns (102) are made from material which is compatible with epitaxial growth of GaN, and the ratio D/d of the height D of one column to the distance d between two neighbouring columns is greater than or equal to 1.5. |
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Composite optical material and method for production thereof Composite optical material has a base in form of a transparent substrate wafer made from ZnSe, which is grown by chemical vapour deposition (CVD) whose polished surface is coated with a protective layer of ZnS, which is obtained by physical vapour deposition (PVD), wherein adhesion of the ZnSe substrate wafer to the protective layer of ZnS is provided by an optically transparent transition layer in form of a continuous row of solid solutions ZnSexS1-x, where x varies from 0 to 1, by interdiffusion of sulphur and selenium into the ZnSe and ZnS layers, respectively. |
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Invention refers to the method for obtaining monocrystalline aluminium nitride that is included in composition of light-emitting diodes and laser elements Device includes crucible 9, in inner part of which there contained is initial aluminium nitride 11 and inoculating crystal 12 placed so that it can be located opposite initial aluminium nitride; at that, crucible 9 consists of internal crucible 2 with initial aluminium nitride 11 and inoculating crystal 12 inside it; at that, internal crucible is corrosion-resistant to sublimate gas of initial aluminium nitride and includes a single metal housing having ionic radius that exceeds ionic radius of aluminium, or contains metal nitride; and external crucible 4 made from boron nitride that covers internal crucible 2 In addition, crucible 9 can contain graphite crucible 6 covering external crucible 4. |
Another patent 2513820.