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Invention relates to technology of producing coloured diamond materials, which can be applied as precious stones or cutting instruments. Method includes stages of growing monocrystalline diamond material in accordance with CVD-technology, with diamond material having concentration of single substituting nitrogen atoms [Ns 0] less than 1 ppm; initial CVD-diamond material is colourless, or, in case it is not colourless, then, according to colour gradation brown or yellow, and if it is brown according to colour gradation, then it has level G (brown) of colour gradation or better for diamond stone with 0.5 carat weight with round diamond cut, and if it is yellow according to colour gradation, it has level T (yellow) of colour gradation or better for diamond stone with 0.5 carat weight with round diamond cut, and irradiation of initial CVD-diamond by electrons to introduce isolated vacancies into diamond material in such a way that product of the total concentration of vacancies × way length [Vt]×L, in irradiated diamond material at said stage or after additional processing after irradiation, including annealing irradiated diamond material at temperature at least 300°C and not higher than 600°C, constitutes at least 0.072 ppm cm and not more than 0.36 ppm cm. |
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Method of forming high-quality heterostructures of light-emitting diodes Invention can be used to produce high-quality semiconductor light-emitting diodes (LED) based on heterostructures of A3B5 compounds. The method includes irradiating a plate with heterostructures with integral electron flux with density of 1014-1017 el/cm2 and energy of 0.3-10 MeV at a temperature not higher than minus 70°C, followed by rapid thermal annealing at a temperature higher than 600°C with photon flux in the visible spectrum with radiation intensity of 1-10 W/cm and energy higher than the band-gap of the semiconductor layer of the heterojunction the narrowest band-gap. |
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Method of processing monocrystalline cvd-diamond and obtained product Invention can be used in obtaining jewellery diamonds. method of introduction of NV-centres in monocrystalline CVD-diamond material includes the following stages: irradiation of CVD-diamond material, containing single substituting nitrogen, for introduction of isolated vacancies in concentration at least 0.05 ppm and at most 1 ppm; annealing irradiated diamond to form NV-centres from at least some of defects of single substituting nitrogen and introduced isolated vacancies. |
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Inventions can be used in chemical and jewellery industry. Nitrogen-doped diamond material, obtained in accordance with CVD technology, or representing monocrystal or precious stone, demonstrates difference of absorptive characteristics after exposure to radiation with energy of at least 5.5 eV, in particular UV radiation, and thermal processing at temperature 798 K. Defects into diamond material are introduced by its irradiation by electrons, neutrons or gamma-photons. After irradiation, difference in absorptive characteristics decreases. |
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Method for low-temperature growth of silicon oxide Invention relates to low-temperature micro- and nanoelectronic techniques and can be sued to design radiation-proof integrated circuits and power semiconductor devices. Silicon oxide is obtained by heating silicon in an oxygen atmosphere to 250-400°C with a stream of electrons with density in the range of 2.5·1013-1014 cm-2·s-1 with energy of 3.5-11 MeV. |
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Method of forming high-quality mos structures with polysilicon gate Invention relates to microelectronics and can be used to produce high-quality, high-power double-diffused MOS transistor, CMOS integrated circuits and CCD devices. The method includes thermal annealing of MOS structures in the temperature range of 600-850°C in an electric field with field intensity of 10-100 V/cm, while simultaneously irradiating with light in the visible and near-infrared spectrum in the wavelength range λ=0.5-1.4 mcm with radiation intensity of 1-10 W/cm2 and with a polysilicon gate with thickness of not more 0.6 mcm on an oxide located on a silicon substrate. |
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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 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 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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Method of diamond heat treatment 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. |
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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. |
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Method of producing diamond structure with nitrogen-vacancy defects 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. |
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Method of cleaning large crystals of natural diamonds 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. |
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Procedure for production of diamonds of fantasy yellow and black colour 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. |
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Procedure for radiation of minerals 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. |
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Device for irradiating minerals 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. |
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Polarisation method of monocrystal of lithium tantalate 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. |
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Method of producing mono-crystalline plates of arsenide-indium 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. |
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Method of obtaining minerals and device for its realisation 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. |
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Method comprises steps of acting upon crystal with electron beam whose integral flux is in range 5 x 1015 - 5 x 1018 electron/cm2; annealing crystal in temperature range 300 - 1900°C and acting with electron beam in condition of electric field having intensity more than 10 V/cm at least upon one local zone of crystal for imparting desired color tone to said zone. Local action of electron beams is realized through protection mask. As irradiation acts in condition of electric field local flaws such as bubbles or micro-inclusions are effectively broken. |
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Proposed method includes stage-by-stage treatment of diamond by mixture of acids under action of microwave radiation; at first stage, use is made of nitric acid and hydrogen peroxide at volume ratio of components of 10:1, respectively; at second stage, volume ratio of mixture of concentrated nitric acid, hydrochloric acid and hydrofluoric acid is 6:2:1, respectively; diamond is treated at temperature not higher than 210°C, pressure of 35 atm as set by loading ratio of autoclave equal to 1:10 at power of oven of microwave radiation of 1200 W; duration of each phase does not exceed 40 min. Proposed method ensures perfect cleaning of diamonds from contamination of mineral and organic nature including bitumen compounds on surface and in cracks of diamond. |
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Method for treating colored diamonds and brilliants for decolorizing them and releasing stresses Method is realized due to physically acting in closed reaction space upon samples of diamonds and brilliants by means of high pressure and temperature for time period sufficient for enhancing their quality. Pressure acting upon samples is in range 6 - 9 GPa in region of thermodynamic stability. Temperature during physical action upon samples is in range 1700 - 2300°C. Samples are subjected to physical action in medium of graphite powder filling reaction space. Heating till high temperature is realized due to applying AC to samples of diamond or brilliant through graphite powder at specific electric current power from 0.18 kWt/cm3 and more. Then electric power is gradually increased from zero till working value and further it is decreased and increased at least two times for some time interval at each change of electric power. Process of annealing samples is completed by smoothly lowering electric current power till zero. At physical action upon sample electric current intensity is lowered by 11 - 13 % and it is increased by 15 - 17 % for time interval from 8 min and more at each change of electric power. Sample is AC heated and it is cooled at rate no more than 0.05kWt/min per cubic centimeter of reaction volume of chamber. |
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Method of shaping high-melting and chemically stable materials Method comprises etching the surface of articles made of high-melting chemically stable materials by applying the layer of an agent interacting the article material and heating the surface by laser pulse irradiating. The surface of the article is simultaneously affected by the laser pulses and vapors of a volatile composition, which is subjected to the pyrolytic decomposition to produce the above mentioned material. The amplitude of the laser pulse should be sufficient to cause the evaporation of the material. |
Another patent 2551363.