1402 results about "Crystal growth" patented technology

Crystal growth systems with a baffle are provided. In one example, a crystal growth system for growing crystalline material, the crystalline material including silicon carbide, includes a seed holder configured to hold a silicon carbide seed crystal. The seed crystal provides a growth surface for growth of the silicon carbide crystalline material. The system includes a crucible at least partially defining a crystal growth chamber. The system includes a source material. The system includes one or more baffles within the crystal growth chamber and spaced apart from the source material. The one or more baffles include one or more apertures defined through the one or more baffles. The baffle includes a long dimension that is non-perpendicular to the growth surface of the seed crystal.

The invention provides a method for preparing an iron-based superconducting material single crystal in a microgravity environment, and belongs to the field of superconducting materials. The method specifically comprises the following steps: carrying out a microgravity crystal growth experiment in a high-temperature experiment cabinet of a space station, putting a solid-phase sintered or pre-melted rod-like raw material into a furnace body, heating and melting, then slowly solidifying, and finally growing the iron-based superconducting material single crystal with large size and extremely low defect density.

The invention provides a crystal growth device and a crystal growth method, and solves the technical problems of low wafer utilization rate, low crystal growth speed, low efficiency, poor uniformity and the like in the existing chip manufacturing process. According to the invention, a traditional cylindrical ampoule structure is abandoned, and the annular ampoule design is innovatively adopted, so that the crystal grows into an inner hollow cylinder shape which is highly matched with the specification of a target wafer; the heater is arranged on the inner side of the ampoule, a traditional outer side heating mode is replaced, and heat is intensively acted on crystals in cooperation with an adjusting center of a heat preservation material during crystal growth, so that heat loss is reduced; the periphery of the heater is made of heat insulation materials, heat radiation leakage is effectively restrained, meanwhile, the ampoule supporting structure is adjusted, and the whole device is simple, low in cost and light in weight.

An object of the present invention is to provide a novel technique capable of manufacturing a large-diameter AlN substrate.The present invention is a method for manufacturing an AlN substrate, including a crystal growth step S30 of forming an AlN layer 20 on a SiC underlying substrate 10 having through holes 11. In addition, the present invention is a method for forming an AlN layer including the through hole formation step S20 of forming the through holes 11 in the SiC underlying substrate 10 before forming the AlN layer 20 on the SiC underlying substrate 10.

The invention provides a crystal growth device and a crystal growth method for separating crystals from melts, and solves the defect that polycrystals are easy to generate during crystal growth at present. The growth device comprises a heat preservation furnace, a heater, a crystal growth crucible, a lining crucible, a lifting mechanism, a ceramic lifting seat, pressing graphite, a heat conduction graphite ring and a heat preservation ring, the crystal growth crucible is coaxially arranged in the heat preservation furnace; the heater is coaxially arranged between the crystal growth crucible and the holding furnace; the lining crucible is coaxially arranged in the crystal growth crucible and comprises a crucible bottom plate, a melt transmission channel and a crucible main body which are coaxial and communicated from bottom to top; in order to reduce the influence of the melt on the crystal in the growth process, the crystal and the melt are physically separated, the growth device with the two crucibles is designed, and in consideration of the importance of stable crystal growth thermal field environment, heat transfer of the two crucibles is isolated through the heat preservation ring; the heat-conducting graphite is used for uniformizing the temperature of the center and the edge of the melt, and concave liquid surfaces are avoided.

The invention discloses an artemisinin extraction intelligent tracking and identification method, and relates to the technical field of image data processing. According to the method, an integrated closed-loop system is constructed through cooperation of four core technical means: based on classified filtering of foam stability difference and bimodal adaptive segmentation, dynamic foam is accurately removed, and preliminary interface extraction is optimized; the attention enhancement U-Net network is embedded into a channel attention module and an edge enhancement branch to realize accurate positioning and fluctuation tracking of a layered interface; the attention mechanism dynamically adjusts the bimodal weight, and completes multi-index cooperative tracking in combination with a partitioning strategy and an improved network; a crystal growth model is introduced to correct particle weight, a tracking effect is optimized by adopting layered resampling, and a closed-loop feedback mechanism of a crystal state and process parameters is established. All technical means are deeply coordinated, intelligent and accurate management and control of the whole extraction process are achieved, and reliable technical support is provided for artemisinin extraction production.

The utility model discloses a fine-grain nanocrystalline homogenization magnetic field stirring crystallizer capable of achieving an ecological cold-water-free accompanying system, and relates to the technical field of non-ferrous metal casting, the fine-grain nanocrystalline homogenization magnetic field stirring crystallizer comprises a fixed stirring assembly and a movable stirring assembly, and the fixed stirring assembly comprises a plurality of fixed coils evenly distributed on the periphery of the crystallizer; the movable stirring assembly comprises a plurality of movable coils evenly distributed on the periphery of the fixed stirring assembly, the movable coils and the fixed coils are distributed in an included angle mode, and the movable stirring assembly is configured to rotate and move relative to the fixed stirring assembly, so that the movable coils can be correspondingly matched with the fixed coils in the local area. Composite magnetic field distribution is formed in a corresponding local area, so that the magnetic field distribution condition of the local area is accurately adjusted, local directional stirring of the melt is achieved, the stirring effect of the melt is accurately controlled, it is ensured that the melt in each area can be uniformly stirred, and therefore the temperature cooling uniformity is improved, and the crystal growth quality and stability are guaranteed.

In a first step S101, the raw material is directly induction heated using a high-frequency induction heating coil (103) while cooling the outer periphery of a raw material (151) to or below the melting point of the raw material by a cooling mechanism (102) to form a raw material melt (152) (raw material melting step). In a second step S102, a seed crystal (161) is brought into contact with the melt (seeding step). In a third step S103, a crystal (153) is grown from the seed crystal (crystal growth step). In the third step S103, the high-frequency induction heating coil and the seed crystal are gradually separated from each other while maintaining the relative distance between the high-frequency induction heating coil and the outer periphery of the raw material, and the crystal is grown in the melt.

The invention discloses a growth device and method suitable for mass production of crystals by a fluxing agent method / liquid phase method. The growth method comprises the following steps: putting a seed crystal and a liquid phase growth raw material into a first growth container, putting the seed crystal into a second growth container, keeping the temperature of a first temperature zone at a first temperature T1, keeping the temperature of a second temperature zone at a second temperature T2, keeping the temperature of a third temperature zone at a third temperature T3, other growth conditions required by crystal growth are provided in the growth chamber; and rotating the rotary lifting frame to drive the second growth container and the seed crystal carried by the second growth container to rotate along a selected rotating track, so that the second growth container and the seed crystal carried by the second growth container are repeatedly transferred between the first temperature zone and the second temperature zone and are repeatedly immersed into the liquid phase growth raw material in the first growth container. The method can be used for industrially producing high-quality single crystals such as gallium nitride with different sizes in batches, and the production efficiency and quality are improved.

The invention discloses a preparation method and application of an MFI zeolite membrane.The preparation method comprises the steps that an MFI zeolite nanosheet serves as a seed crystal, a uniformly-distributed and compact seed crystal layer is prepared on a carrier through a vacuum filtration method, namely, a nucleation center crystallized into a membrane is loaded on the surface of the carrier, and directional growth and membrane forming of the zeolite nanosheet can be effectively controlled; the highly b-oriented MFI zeolite membrane can be prepared within several hours, the prepared b-oriented MFI zeolite membrane shows a continuous and compact microstructure and almost has no defects, and compared with a traditional hydrothermal method, the method overcomes the defects that the reaction process is too long in time consumption, uneven in heating is prone to occurring, and the like. And therefore, the time required by crystal growth is greatly shortened. The prepared MFI zeolite membrane can be applied to pervaporation separation of xylene isomers, shows good size screening separation performance, and has important industrial application value.

The invention discloses an inflation method for regulating and controlling the growth rate of silicon carbide crystals and a related device, and relates to the technical field of semiconductors, and the inflation method comprises the following steps: obtaining the mass loss rate of a silicon carbide crystal growth system based on a weighing sensor; the quality loss rate is compared with a theoretical loss rate, a deviation rate is obtained, and the theoretical loss rate is the quality loss rate meeting the production requirement under the current technology; acquiring a growth stage parameter, judging whether the growth stage parameter reaches a preset value or not, if the growth stage parameter reaches the preset value, adopting a first control strategy, and if the growth stage parameter does not reach the preset value, adopting a second control strategy, the growth stage parameters comprise the silicon carbide crystal thickness corresponding to the preset crystal growth time. According to the method, the uniformity of the resistivity of the silicon carbide crystal is improved by regulating and controlling the doping gas proportion in the growth process of the silicon carbide crystal.

The invention relates to the technical field of iron phosphate preparation, in particular to a preparation method of low-impurity iron phosphate with a high iron-phosphorus ratio, which at least comprises the following steps: preparing an iron source solution and a phosphorus source solution; mixing an oxidizing agent and a phosphorus source solution as a phosphorus source mixed solution; adding the phosphorus source mixed solution into the iron source solution, and controlling the molar ratio of iron to phosphorus to be 1: (1.1-1.3) to prepare slurry; dividing the slurry into two parts, respectively adding an impurity removal agent, and then carrying out segmented aging at 90 DEG C to prepare crystallized slurry; and filtering, washing, drying and calcining the crystallized slurry to obtain a target product iron phosphate finished product. The impurity removal agent is selected from one or more of ferrous sulfate, ferrous chloride, ferrous nitrate and ferrous oxalate. Seed crystals are formed through segmented aging crystal transformation to promote crystal growth, and autonomous grain size distribution is achieved; an impurity removing agent is added in the aging stage, impurities are reduced by using the same ion effect, the iron-phosphorus ratio is increased, and the compaction density and the electrical property of the prepared lithium iron phosphate are remarkably improved.

The invention relates to the technical field of crystal growth, in particular to a device and a method for diversion growth of silicon carbide single crystals. The invention provides a device for diversion growth of silicon carbide single crystals. The device comprises a crucible, a first rotary lifting shaft and a turbine liquid pump kit, the turbine liquid pump kit comprises a flow guide baffle, the upper portion of the flow guide baffle is connected with the first rotary lifting shaft, a seed crystal support with seed crystals is installed on the lower portion of the flow guide baffle, turbine blades are installed on the flow guide baffle and evenly distributed around the seed crystals, and the height of the lower ends of the turbine blades is smaller than that of the seed crystals. The invention provides a device and a method for diversion growth of silicon carbide single crystals, which can improve the transmission stability and transmission efficiency of solute in a solution and improve the long-time growth stability of crystals.

The invention belongs to the technical field of SiC crystal growth, and particularly relates to a thermal field component for SiC crystal growth and a preparation method of the thermal field component. The thermal field component comprises a thermal field component body, and the thermal field component body is made of a porous tantalum carbide material. The thermal field component can efficiently filter carbon particles, has corrosion resistance and long service life, and can remarkably reduce the production cost.

Crystal growth systems for growing crystalline material comprising silicon carbide are provided. In one example, the crystal growth system includes a crucible at least partially defining a crystal growth chamber. The crystal growth chamber has a plurality of zones, each zone associated with a different processing profile. The system includes a silicon carbide crystal. The system includes a source material.

The invention discloses a fracturing proppant using coal gangue and fly ash and a preparation process thereof, and relates to the field of fracturing proppants, the fracturing proppant comprises coal gangue, fly ash, silica fume, nanometer alumina, a composite pore-forming agent and a fluxing agent, and the preparation process comprises raw material pretreatment, mixing granulation, microwave-gradient sintering and post-treatment. The raw material pretreatment comprises the following steps: removing iron and impurities through carbon thermal reduction-magnetic separation; the composite pore-forming agent is enriched on the surface of the green body during mixed granulation; the microwave-gradient sintering is used for cooperatively regulating and controlling growth of mullite crystals through microwave preheating and resistance heating to form an internal acicular mullite interlaced structure and a surface micro-convex structure; a finished product is obtained through post-treatment grading and surface cleaning. Resource utilization of industrial solid waste is achieved, the strength and flow conductivity of the proppant are improved through raw material synergy, crystal structure regulation and control and surface microstructure design, preparation energy consumption is reduced, and the proppant is suitable for oil and gas field fracturing engineering.

A device for crystal growth and a crystal growth method. The device comprises a seed crystal holder, a seed crystal connecting rod, and a state detection assembly. The seed crystal holder is connected to one end of the seed crystal connecting rod, and the state detection assembly is configured to detect a seed crystal holder state of the seed crystal holder, wherein the seed crystal holder state reflects the state of the seed crystal holder relative to a melt, and the melt is used for crystal growth.

The invention discloses an intelligent energy-saving regulation and control system and method for a silicon single crystal thermal field. The system comprises a multi-physical field acquisition unit, a thermal field simulation calculation module, a gradient thermal insulation assembly, an AI regulation and control module, a feedback execution control module and an energy consumption evaluation module. The system constructs a coupling temperature field / flow field model by collecting temperature, flow velocity and pressure data in a furnace in real time, generates a dynamic control strategy by using an AI algorithm, and drives a heater, a cooling system and an adjustable graphite felt assembly to cooperatively respond; the gradient heat insulation assembly adapts to heat flow distribution through the axial heat conductivity decreasing design, and heat loss is reduced. The method comprises the steps of data acquisition, simulation modeling, AI strategy generation, execution control, quality evaluation and model correction, and closed-loop optimization is formed. The method realizes intelligent dynamic regulation and control of thermal field distribution, remarkably improves crystal growth quality and energy efficiency, and is suitable for the field of semiconductor silicon single crystal preparation.

The invention discloses a linkage regulation and control method and system for a vacuum environment, and belongs to the technical field of vacuum environment regulation and control, and the method specifically comprises the steps: collecting time sequence data of a crystal growth environment in real time, constructing a temperature-vacuum-growth stage three-dimensional mapping relation, and dynamically correcting a vacuum threshold value by combining a furnace body material thermal expansion deformation compensation algorithm. Generating a multi-parameter coupling vacuum regulation and control model; generating a dynamic vacuum threshold curve of each growth stage based on a vacuum regulation and control model, and outputting a cooperative control signal through real-time deviation calculation; a three-level linkage control strategy is adopted to maintain the vacuum degree stable, a long-short-term memory network is utilized to predict the change trend of the vacuum degree, and a standby vacuum unit is activated in advance; a distributed optical fiber strain sensor is used for detecting leakage sound wave characteristics of a sealing surface, positioning a failure point and driving a magnetic compensation plug to perform dynamic plugging, and meanwhile, leakage information is fed back to a vacuum regulation and control model, so that closed-loop optimization is realized; the vacuum degree control precision and the equipment reliability in the crystal growth process are improved.

The invention discloses an electrolyte for water system energy storage and a preparation method and application thereof, and belongs to the technical field of electrochemical energy storage, the electrolyte for water system energy storage comprises a mixed salt and a mixed solvent, the mixed salt comprises a metal salt and an organic salt; the mixed solvent comprises water and an aprotic organic solvent; the organic salt is trifluoromethanesulfonate containing imidazole cations. Through the ion-solvent synergistic effect, an anion-rich and water-poor double-electrode-layer structure is formed on an electrode interface, dendritic crystal growth and side reaction are remarkably inhibited, and meanwhile high ionic conductivity is kept. The aqueous battery prepared from the electrolyte has good cycling stability and excellent practical performance under the conditions of low N / P ratio and low current density.

The utility model discloses an atmosphere maintaining device for a vacuum crystal growing furnace, which relates to the technical field of crystal growing furnaces, and comprises a crystal growing furnace body, a reaction cavity is arranged in the crystal growing furnace body, and the outer side wall of the crystal growing furnace body is fixedly connected with a mounting frame. A gas control unit is arranged at the upper end of the mounting frame, a gas extraction unit is arranged at the upper end of the crystal growth furnace body, the gas control unit comprises two gas storage tanks fixedly connected to the upper end of the mounting frame, and first gas extraction pumps are fixedly connected to the upper ends of the two gas storage tanks; the output ends of the two first sucking pumps are fixedly connected with conveying pipes correspondingly, and adjusting sleeves are installed on the outer side walls of the two conveying pipes correspondingly. The air exhaust unit is arranged, so that the air pressure in the reaction cavity can be adjusted, and the air pressure in the reaction cavity is kept stable; and by arranging the gas control unit, different gases can be injected into the reaction cavity, so that the atmosphere in the reaction cavity is kept stable.

The invention discloses a single-crystal lithium-rich manganese-based positive electrode material as well as a preparation method and application thereof. The preparation method of the single-crystal lithium-rich manganese-based material comprises the following steps: synthesizing a nickel-cobalt-manganese hydroxide as a precursor by using a coprecipitation method, then fully mixing the precursor with a lithium source, and then preparing the single-crystal lithium-rich manganese-based positive electrode material by adopting a stepped sintering schedule in combination with a high-temperature-section short-time low-oxygen-partial-pressure mixed atmosphere. According to the method, a stepped sintering schedule is adopted, the conditions such as the temperature, the heating and cooling rate and the atmosphere during sintering are reasonably regulated and controlled, the stepped sintering schedule is beneficial to optimizing the processes such as crystal crystallization, crystal growth and crystal defect repair, the short-time low-oxygen-partial-pressure mixed atmosphere in the high-temperature section is beneficial to achieving better crystal domain dispersion, the staggered structure of the Li2MnO3 phase is improved, and the performance of the lithium ion battery is improved. And finally, the micron-sized single-crystal lithium-rich manganese-based positive electrode material with good grain size consistency is obtained.

The invention discloses an oxygen-enriched destressing crystal growth method and a crystal growth furnace, and relates to the technical field of crystal growth, and the oxygen-enriched destressing crystal growth method comprises the following steps: step 1, pre-treating a PMNT polycrystal material, and putting the pretreated PMNT polycrystal material into a crucible; 2, pre-flushing the growth furnace and creating an oxygen partial pressure environment; 3, raising the temperature in the growth furnace to melt and homogenize the PMNT polycrystal material in the crucible; step 4, the crucible moves downwards for directional solidification of the crystal, a solid-liquid interface is formed and stably moves upwards, and in the process, a dynamic regulation and control strategy is adopted in the growth furnace to control an oxygen-enriched environment to promote crystal growth, so that the crystal digests growth stress in the growth process, and formation of oxygen vacancies is inhibited; and step 5, after crystal growth is finished, gradient cooling is performed to room temperature in an oxygen-enriched environment, and a crystal ingot is obtained. Oxygen is used as a regulation and control tool, the stress problem caused by oxygen vacancy is physically solved, the color center and performance problems caused by oxygen vacancy are chemically solved, and the crystal growth quality is improved.

The invention provides a seed crystal bonding method for inhibiting back sublimation of SiC, and belongs to the technical field of silicon carbide crystal growth treatment. A laser annealing mode is adopted, laser is used as a heat source, after the laser passes through a transmission system, a laser beam with uniform energy distribution can be generated and is projected to the surface of the silicon carbide seed crystal, silicon carbide on the surface layer absorbs the energy of the laser to be melted and then decomposed into carbon and silicon, the melting point of the silicon is low, and the silicon escapes after being melted and gasified; and the left carbon can form a compact carbon film on the surface layer of the silicon carbide. The production cost is reduced, the production efficiency is improved, meanwhile, the problem of back sublimation during SiC growth is solved, and the success rate of seed crystal bonding and the SiC crystal quality are both improved.

The invention belongs to the technical field of metal powder preparation, and particularly relates to a preparation method of copper powder. According to the method, the pH value of a reduction reaction system is precisely regulated and controlled to be within the range of 5.38-9.38, the dispersing agent is reasonably added in stages before and after pH regulation, and the copper powder with the small average particle size and the low variable coefficient is successfully prepared. From the perspective of the process principle, the accurate regulation and control of the pH value can influence the crystal growth kinetics of copper hydroxide by adjusting the proton concentration, and directionally induce the copper hydroxide to form a target crystal form with a regular structure and uniform morphology, thereby laying a foundation for uniform nucleation and growth of copper atoms in the subsequent reduction reaction; by adding the dispersing agent in stages, the steric hindrance effect and the interface adsorption effect of the dispersing agent can be synergistically exerted, copper hydroxide particles are effectively inhibited from being agglomerated in the early stage, copper particles are prevented from being agglomerated due to too high local concentration in the reduction process in the later stage, and the consistency of the particle size is further guaranteed.

The invention belongs to the technical field of semiconductor crystal growth, and particularly relates to a magnetic field dynamic adaptation system and method for improving single crystal oxygen content uniformity, the melt liquid level height H is sensed in real time through a liquid level position sensing unit, thermal field state data W is obtained through a temperature zone monitoring unit, and the single crystal oxygen content uniformity is improved on the basis of the melt liquid level height H and the thermal field state data W. And the control module converts the target position Pz into a driving instruction and sends the driving instruction to the magnetic field execution module to drive the magnetic field execution module to synchronously and dynamically adjust the magnetic field space position of the magnetic field generator, converts the target intensity Btarget into a driving instruction and sends the driving instruction to the magnetic field execution module to drive the magnetic field execution module to synchronously and dynamically adjust the magnetic field intensity of the magnetic field generator. The magnetic field space position of the magnetic field generator is dynamically adjusted to promote oxygen to be conveyed uniformly, so that the radial oxygen concentration CV value is reduced, the magnetic field intensity of the magnetic field generator is dynamically adjusted to avoid nonlinear fluctuation in the oxygen segregation process, and the linearity of an axial oxygen distribution curve is improved.

Systems and methods for defect mitigation in silicon carbide crystal growth systems are provided. In an aspect, an example method includes providing a crystalline material in a first zone of the crystal growth chamber. In some implementations, the example method includes providing a silicon carbide vapor source material in a second zone of the crystal growth chamber. The example method includes providing an etching agent in the crystal growth chamber. The example method includes controlling a temperature gradient in the crystal growth chamber such that a first temperature in the first zone is greater than a second temperature in the second zone to implement an etching process on the crystalline material in the crystal growth chamber.

The invention discloses a crystal growth method for avoiding formation of a gallium oxide polycrystal shoulder, and belongs to the technical field of crystal growth. The length of the slit on the surface of the mold is designed to be not more than one third of the length of the mold, and melt supply is strictly limited in a local area of the slit in a seeding stage, so that accurate starting of single crystals is realized; and then, in a crystal lateral expansion stage, actively regulating and controlling the interval between the upper surface of the mold and a crystal growth interface, so that a melt layer in the interval is used as a dynamic and expandable raw material supply channel. Therefore, the technical prejudice that a traditional edge-defined film-fed method depends on full-length solid slit feeding penetrating through a mold is broken through, a melt exposure area is reduced to be near a growth interface, spontaneous nucleation of a melt in a non-target area is fundamentally inhibited, formation of a polycrystal shoulder (square shoulder) is effectively avoided, raw material volatilization is remarkably reduced, thermal field uniformity is improved, and the method is suitable for large-scale production. And the crystal quality, the growth stability and the process efficiency are improved.

The present application relates to the technical field of identification during crystal growth, and specifically relates to a method for identifying and detecting the edges and corners of a seed crystal single crystal wire in a crystal growth process, comprising four steps, i.e., constructing a high-quality data set, constructing an artificial intelligence algorithm model, performing model training, and performing model evaluation and verification. The present invention overcomes the defects of manual determination of the starting time of a seeding procedure, and provides a method for automatically determining the seeding time, so that a control system automatically controls the operation of starting the seeding procedure after temperature adjustment is ended.

The invention discloses a method for decalcifying by selectively precipitating magnesium ions in high-calcium and high-magnesium wastewater. The method comprises the following steps: pretreating the high-calcium and high-magnesium wastewater, filtering to remove impurities, and adjusting the pH value to obtain a pretreatment solution with the pH value of 9.5-10.5; adding phosphate into the pretreatment liquid to carry out auxiliary precipitation, so that Mg (OH) 2 crystals grow to obtain reaction slurry; introducing the reaction slurry into a sedimentation tank to settle Mg (OH) 2 crystals, and introducing supernate in the sedimentation tank into a decalcification tank; adding 100-200mg / L of polyaluminum chloride and 5-10mg / L of polyacrylamide into the decalcification tank, stirring and reacting, and introducing the reaction liquid into a decalcification sedimentation tank; carrying out solid-liquid separation in the decalcification sedimentation tank to obtain decalcified supernate; and carrying out deep decalcification on the decalcified supernate by using a selective ion exchange method. The method creates conditions for selective precipitation calcium removal and magnesium ion crystallization recovery of the high-calcium and high-magnesium wastewater.