30 results about "Boron trichloride" patented technology

The present invention discloses a boron-containing, high-temperature-resistant, near-stoichiometric silicon carbide fiber and a preparation method thereof. The preparation method includes a spinning stage, an infusibility stage, a pre-sintering stage, a densification sintering stage, and a nitriding stage, and is characterized in that: in the infusibility stage, the metal-doped polycarbosilane precursor fiber obtained in the spinning stage is subjected to a boron-doping reaction in an atmosphere containing boron trichloride and a cross-linking reaction in an atmosphere of a gaseous hydrocarbon having a carbon-carbon double bond. The method is simple to operate, has high production efficiency, low production cost, and is easy to use for large-scale industrial production. The prepared boron-containing, high-temperature-resistant, near-stoichiometric silicon carbide fiber has the advantages of low oxygen content, high degree of densification, few defects, stable structure, high tensile strength modulus, large grain size, and good high-temperature resistance, oxidation resistance, and creep resistance.

The invention provides a preparation method and device of Bi2O3-B2O3 inverse magnetic rotation glass, and the preparation method comprises the following steps: (1) placing a glass raw material in a closed heating furnace, introducing ultra-dry oxygen, and simultaneously exhausting outwards to enable the pressure in the furnace body to be P1 which is more than or equal to 1kPa and less than or equal to 5kPa; (2) heating to melt the glass raw material in the furnace body into molten glass, raising the temperature to a clarification temperature, introducing the mixed gas into the molten glass by a bubbling method, simultaneously homogenizing and stirring, and stopping introducing the mixed gas and starting defoaming and stirring when the homogenizing and stirring time reaches t1; wherein the mixed gas comprises ultra-dry oxygen and boron trichloride, the volume ratio of the ultra-dry oxygen to the boron trichloride is k, and k is (1-5): 1; (3) cooling, forming, annealing and pouring; in the step (2) and the step (3), the pressure in the furnace body is kept P1. The Bi2O3-B2O3 diamagnetic optical rotation glass prepared by the method disclosed by the invention is stable in magneto-optical performance and low in hydroxyl absorption coefficient in a middle-infrared band.

The invention provides a TOPCon battery and a preparation method thereof, and boron diffusion equipment, and the preparation method of the TOPCon battery comprises the steps: providing a silicon substrate, placing the silicon substrate in a boron diffusion furnace, introducing nitrogen into a furnace mouth region of the boron diffusion furnace, introducing oxygen and boron trichloride into the boron diffusion furnace, introducing nitrogen gas into the furnace mouth region of the boron diffusion furnace, introducing nitrogen gas into the furnace mouth region of the boron diffusion furnace, introducing nitrogen gas into the furnace mouth region of the boron diffusion furnace, and introducing nitrogen gas into the furnace mouth region of the boron diffusion furnace, the ratio of the flow of the oxygen to the flow of the boron trichloride is alpha, and alpha is more than or equal to 3.5 and less than or equal to 4.5. The nitrogen can quickly purge reaction byproducts in a low-temperature area of the furnace mouth, and sufficient oxygen is provided to completely oxidize boron trichloride into a gaseous boron oxide precursor before the boron trichloride enters a high-temperature reaction area, so that the generation of viscous low-temperature boron oxide due to insufficient oxidation is avoided; and the generation and deposition of boron oxide crystals at the furnace mouth are inhibited from two dimensions of mass transfer process and chemical reaction completeness, and the yield and average photoelectric conversion efficiency of the TOPCon battery can be remarkably improved.

Provided is a plasma processing method capable of achieving flat etching process while suppressing vertical etching.The plasma processing method for plasma-etching a titanium nitride (TiN) film that forms a metal gate and contacts an insulating film on both sides includes the step of etching the titanium nitride (TiN) film by using plasmas that are generated by using a mixed gas of boron trichloride (BCl3) gas, nitrogen (N2) gas, and nitrogen trifluoride (NF3) gas and are generated by radio-frequency power modulated by a pulse, wherein the pulse has a first period with a first amplitude as its amplitude and a second period with a second amplitude as its amplitude and wherein the second amplitude is greater than 0 and less than the first amplitude.

The titration bottle comprises a bottle body, the bottom of the bottle body is provided with a base, the inner top of the bottle body is provided with a sealing rubber plug, the sealing rubber plug is filled with a sponge block, and the top of the sealing rubber plug and the top of the sponge block are connected with a bottle cap. A dropper is inserted between the sealing rubber plug and the sponge block, the lower end of the dropper extends into the inner bottom of the bottle body, the upper end of the dropper is connected with an air bag, scale marks are arranged on the front end face of the bottle body, a containing groove is formed in the top of the base, and the bottom of the bottle body is arranged in the containing groove of the base. And a magnet is embedded in the middle of the bottom of the base. Through the arrangement of the base and the magnet, the bottle body is not prone to toppling over when accidentally collided, the safety coefficient is high, the bottle body can be firmly attracted and fixed to an iron working table through the magnet, and the safety in the using process is further improved.

The invention belongs to the technical field of boron trichloride gas detection and analysis, and particularly relates to a gas chromatographic analysis device and method for trace impurities of high-purity boron trichloride. The device comprises a sample gas inlet path used for providing uniform and quantitative sample gas to be detected; the first detection gas path is used for detecting light component impurities; the second detection gas path is used for detecting CO2-containing impurities; and the third detection gas path is used for detecting high-boiling-point impurities. According to the arrangement of the structure and the method, the gas chromatographic analysis device and the gas chromatographic analysis method for the trace impurities of the high-purity boron trichloride, which can realize high efficiency, stability and high precision and can carry out gradient separation through one-time gas inlet, are realized.

The invention belongs to the technical field of ceramic precursors, and particularly relates to a silicon-boron-carbon-nitrogen ceramic precursor with a main chain containing alkynyl and a preparation method of the silicon-boron-carbon-nitrogen ceramic precursor. Comprising the following steps: (1) dropwise adding an n-butyllithium solution into an ether solvent, stirring, continuously dropwise adding trichloroethylene, and reacting to obtain an alkynyl dilithium salt turbid solution; (2) adding boron trichloride into the alkynyl dilithium salt turbid solution to carry out primary dechlorination polycondensation reaction, and dropwise adding dichlorosilane to carry out secondary dechlorination polycondensation reaction after the reaction is completed; (3) adding hexamethyldisilazane into the system in the step (2) to carry out an end-capping reaction, collecting supernate after the reaction is finished, and distilling at normal pressure to remove the solvent, so as to obtain a silicon-boron-carbon-nitrogen ceramic precursor crude product; and (4) dissolving the silicon-boron-carbon-nitrogen ceramic precursor crude product in an organic solvent, carrying out dialysis treatment, and carrying out atmospheric distillation on the solution in a dialysis membrane to remove the solvent so as to obtain the silicon-boron-carbon-nitrogen ceramic precursor with the main chain containing alkynyl, and the ceramic yield of the silicon-boron-carbon-nitrogen ceramic precursor in the high-temperature ceramization process can reach more than 70%.

The present disclosure relates to the technical field of chemical separation, in particular to a preparation method of electronic-grade boron trichloride and the boron trichloride obtained by the same. Before the generation of the target product boron trichloride, firstly metal chlorides are generated by allowing metal impurities to react with chlorine, and since a reaction temperature of the metals and the chlorine is usually 350°C to 450°C, which is less than temperature at which the boron trichloride is generated by allowing boron carbideto react with the chlorine, two products can be generated separately under a temperature control condition. The generated metal chlorides have been vaporized at 400°C to 450°C, and are exhausted along with unreacted chlorine. After the metal impurities are removed, reaction between the boron carbide and the chlorine is performed, to generate the target product boron trichloride. According to the present disclosure, the metal chloride impurities can be deeply removed from the boron trichloride, and a removal rate reaches 95% or above. Other impurities are effectively removed through the combination of adsorption and rectification, and purity of the obtained boron trichloride reaches 99.999%, which meets 5N standards.

The invention discloses a hole transport material, a preparation method thereof and a perovskite solar cell, the hole transport material has a structure as shown in a formula 1, and the preparation method of the hole transport material comprises the following steps: S1, adding 4, 5-dichlorophthalonitrile, phenylacetylene and a catalyst into a solvent for mixing, performing a first heating reflux reaction in an inert atmosphere to obtain a product as shown in a formula 2; and S2, mixing the product as shown in the formula 2, boron trichloride and an organic solvent, and carrying out a second heating reflux reaction in an inert atmosphere to prepare the hole transport material. According to the hole transport material, subphthalocyanine is used as a core skeleton, modification is carried out through peripheral phenylacetylene groups, a pi conjugated system is remarkably expanded while the basic structure of subphthalocyanine is maintained, and therefore the photoelectric conversion efficiency of a perovskite solar cell is improved; in addition, the hole transport material is good in thermal and chemical stability and has hydrophobicity, so that the service life of the perovskite solar cell is prolonged, and the stability of the perovskite solar cell is improved.

The invention discloses a catalyst for synthesizing p-cumylphenol and a preparation method thereof. The catalyst comprises an active component A, a carrier B and a cocatalyst C. The active component A is one or more of aluminum trichloride, tin tetrachloride, zinc chloride, ferric chloride and boron trichloride. The carrier B is one or more of silica gel and aluminum oxide; the cocatalyst C is one or more of zinc oxide, copper oxide, magnesium oxide, zirconium dioxide, titanium dioxide and boric oxide, the selectivity of the catalyst is high, and p-cumylphenol can be efficiently prepared.

The invention belongs to the technical field of ICP (Inductively Coupled Plasma) etching, and relates to a method for etching gallium oxide by ICP, which comprises the following steps of: placing a gallium oxide sample with a PR mask on a wafer in an ICP etching chamber, introducing a first gas halide and a second gas halide into the front surface of the gallium oxide sample until the interior of the etching chamber is in a stable state, and removing the first gas halide and the second gas halide from the front surface of the gallium oxide sample; continuously introducing each gas and starting radio frequency to carry out etching treatment to obtain etched gallium oxide; the first gas halide comprises boron trichloride, and the second gas halide comprises any one or a combination of at least two of hydrogen bromide, chlorine and trifluoromethane. According to the method, pollution caused by the metal mask to gallium oxide etching can be avoided, the etching roughness can be reduced, the gallium oxide etching perpendicularity can be improved, the bottom of the etched gallium oxide achieves a fillet effect, and compared with a conventional etching method, the selection ratio of gallium oxide to PR is also obviously improved.

An apparatus includes a body configured to support a substrate, a first coating, conformal on a surface of the body, that is corrosion resistant to at least one of: boron trichloride, nitrogen trifluoride, hafnium tetrachloride, aluminum trichloride, oxygen gas, chlorine gas, fluorine gas, chlorine trifluoride, hydrogen fluoride, hydrogen gas, ammonia, tungsten hexafluoride, tetrafluoromethane, titanium tetrachloride, molybdenum pentachloride, ozone, tetrafluorosilane, or hexafluoroethane, and a second coating, on the first coating, having a hardness that greater than or equal to about 8 gigapascals.

The invention discloses a trimethyl boron preparation method and device, namely trimethyl boron is prepared by reaction of trimethyl aluminum and boron trichloride, the conversion rate of boron trichloride can reach 99%, the yield of trimethyl boron is greater than or equal to 95%, the purity is greater than 99%, the method is convenient and low in cost, and the trimethyl boron production process is simpler. Meanwhile, a set of reaction device for continuously preparing trimethyl boron is designed and developed, the reaction device is composed of a feeding system, a reaction system, a temperature control system, a product purification and collection system, a product collection system and a temperature control system, and the method and the device can efficiently produce trimethyl boron.

The invention relates to the technical field of semiconductor power device manufacturing, and discloses a method for improving metal etching residues based on dry etching. The method comprises the following steps: S1, providing a substrate layer; s2, depositing a stop layer on the substrate layer, and forming a pattern on the substrate layer on the stop layer through a photoetching process to serve as a first pattern; s3, performing wet etching on the first pattern to the substrate layer; s4, removing the photoresist in the step S2 by adopting a wet process, depositing a metal composite layer on the stop layer, and forming a pattern on the substrate layer on the metal composite layer through a photoetching process as a second pattern; and S5, the metal composite layer is subjected to metal etching, the stop layer serves as an etching end point, the bias power of metal etching is 200-250 W, and the flow of boron trichloride gas is 40-50 sccm. In this way, the problem of metal residues in the etching process can be effectively solved.

The invention provides a light emitting diode for improving electric leakage and a preparation method thereof, and belongs to the technical field of photoelectron manufacturing. The preparation method of the light-emitting diode comprises the following steps: forming an epitaxial structure on a patterned substrate; the surface, away from the patterned substrate, of the epitaxial structure is bonded to a conductive substrate, and the patterned substrate is removed; the surface, away from the conductive substrate, of the epitaxial structure is etched, a first groove is formed, etching gas comprises chlorine and boron trichloride, the upper power of etching equipment in at least part of stages in the etching process is smaller than or equal to 500 W, and the lower power of the etching equipment in at least part of stages in the etching process is smaller than or equal to 300 W. According to the embodiment of the invention, the problem of over-etching of the epitaxial layer can be improved, and electric leakage caused by short circuit of the film layer after over-etching can be avoided.

The application discloses a SiC nanowire in-situ modified ceramic matrix composite connecting fastener and a preparation method thereof, and belongs to the technical field of ceramic matrix composite materials. The preparation method comprises the following steps: firstly, performing heat treatment on a fiber preform; then, performing CVD or CVI deposition on the fiber preform by using boron trichloride and ammonia gas / ethylene as a precursor; then, performing catalyst solution impregnation and drying; finally, performing CVI deposition on the composite preform by using trichloromethylsilane as a precursor, so that the composite preform is prepared; firstly, performing CVD or CVI deposition on the composite preform by using silicon tetrachloride and ammonia gas as a precursor; then, performing precursor solution impregnation and drying; then, performing vacuum pyrolysis treatment; finally, performing CVI deposition on the composite preform by using silicon tetrachloride and ammonia gas as a precursor, processing threads, and the connecting fastener is prepared. The application realizes rapid densification while reinforcing and toughening by means of in-situ growth of SiC nanowires, and has the advantages of short preparation period, good mechanical properties of products, high connecting efficiency and the like.

Molybdenum is etched in a highly controllable manner by performing one or more etch cycles, where each cycle involves exposing the substrate having a molybdenum layer to an oxygen-containing reactant to form molybdenum oxide followed by treatment with boron trichloride to convert molybdenum oxide to a volatile molybdenum oxychloride with subsequent treatment of the substrate with a fluorine-containing reactant to remove boron oxide that has formed in a previous reaction, from the surface of the substrate. In some embodiments the method is performed in an absence of plasma and results in a substantially isotropic etching. The method can be used in a variety of applications in semiconductor processing, such as in wordline isolation in 3D NAND fabrication.

The application provides a purification method of boron trichloride, which comprises the following steps: removing the size particles in raw material boron trichloride through a filter, removing water through a first adsorption tower, removing phosgene through a second adsorption tower, collecting the boron trichloride after pressure boosting through a crude product tank, removing light components through a first rectification tower, removing heavy components through a second rectification tower, finally detecting the boron trichloride, collecting the boron trichloride to a product storage tank when the detection is qualified, and returning the unqualified product to the first adsorption tower for further purification; and the application also provides a purification device of boron trichloride, which removes water and phosgene in crude boron trichloride through an adsorption tower containing 4A molecular sieve and MOF-74 series fillers, and then purifies the boron trichloride through a second rectification, so that the process flow is simple, and the purity of the product can reach 6N level.

The present disclosure generally relates to semiconductor processing tool cleaning, such as may be included in semiconductor processing for manufacturing an integrated circuit (IC). In an example, a cleaning process is performed on an interior surface of a chamber of a semiconductor processing tool. The cleaning process includes flowing a reactive gas into an interior volume of the chamber. The interior volume is defined at least in part by the interior surface. The reactive gas consists exclusively of boron trichloride (BCl3). After performing the cleaning process, a material layer over a semiconductor substrate is etched in the chamber.

This invention discloses a method for preparing aluminum-containing SiBCN ceramic fibers. The method involves mixing a precursor, polyaluminosilane carbosilane (PACS), and boron nitride powder to obtain a uniform, pale yellow PACS / BN hybrid precursor. This hybrid precursor is then sequentially subjected to melt spinning, air-insoluble treatment, high-temperature pyrolysis, and sintering to achieve densification, resulting in black, dense aluminum-containing SiBCN ceramic fibers. This invention differs from existing methods for preparing SiBCN ceramic fibers by avoiding the use of toxic organic monomers (such as boron trichloride, chlorosilanes, and hexamethyldisilazane) or difficult-to-synthesize polyborosilicate (PBSZ, a precursor for SiBCN ceramic fibers). It offers advantages such as safe and simple operation, economy, mild reaction conditions, and adjustable boron and nitrogen content.

The application provides a production device, a production device control method and a preparation method of a phenyl chlorosilane. The production device comprises a reactor, a catalyst circulation device and a catalyst. The reactor is used for accommodating a reaction raw material and is provided with an outlet and an inlet. The catalyst circulation device is in communication with the outlet and the inlet respectively and is used for driving at least part of the catalyst to circulate in and out of the reactor. The reaction raw material comprises a chlorosilane and a benzene compound, and the catalyst comprises boron trifluoride or boron trichloride. The application can realize the recycling of the catalyst in the production process of the phenyl chlorosilane, separate the catalyst from hydrogen generated in the reaction, improve the reaction efficiency of the catalyst, and thus reduce the production cost of the phenyl chlorosilane.

The invention relates to the technical field of electrical insulating materials and particularly discloses an epoxy resin material for a direct-current wall bushing as well as a preparation method and application of the epoxy resin material. The method comprises the following steps: mixing low-aromatic-ring low-molecular-weight epoxy resin, short-chain epoxy resin containing an ester-group main chain and an anhydride curing agent under vacuum heating, adding a boron trichloride multi-side-chain amine complex, and stirring to obtain a mixed material liquid; and pouring into a mold, and carrying out vacuum standing and stepped heating curing to obtain the required material. The problem that an existing epoxy resin material is difficult to cooperate in heat resistance and breakdown strength in a process window is solved. The prepared material is low in viscosity and wide in process window, is beneficial to full impregnation and defect reduction, has high heat resistance and high breakdown strength, and can guarantee long-term stable operation of the direct-current wall bushing.

The invention discloses a viscous ceramic diaphragm and a preparation process thereof, belonging to the technical field of lithium-ion batteries. The diaphragm comprises a base film and a ceramic coating, wherein the ceramic coating is obtained by coating a ceramic slurry on the base film and drying the ceramic slurry; the ceramic slurry comprises the following raw materials in parts by weight: 10-70 parts of inorganic ceramic particles, 0.5-20 parts of modified sodium carboxymethyl cellulose, 1-10 parts of a plasticizer, 0.5-2 parts of a dispersant, 0.5-1 parts of dopamine, and 10-90 parts of deionized water; boron trichloride, a solvent, dichloromethylsilane, and 1,3-bistrifluoropropyl-1,1,3,3-tetramethyldisilazane are reacted to obtain a mixed intermediate, which is then blended and modified with high-viscosity sodium carboxymethyl cellulose to obtain the modified sodium carboxymethyl cellulose. By introducing the modified sodium carboxymethyl cellulose into the ceramic coating, the ceramic coating and the base film have strong bonding at high temperatures and the ceramic diaphragm has good thermal stability, thereby meeting the requirements of lithium battery technology for the diaphragm.

The invention discloses a light-cured resin system for additive manufacturing of SiBCN ceramic and a preparation method thereof, and the light-cured resin system for additive manufacturing of SiBCN ceramic comprises the following raw material components: vinyl-containing polyborosilazane, mercaptan, a light absorbing agent, a free radical capturing agent and a photoinitiator. The preparation method of the vinyl-containing polyborosilazane comprises the following step: carrying out reaction on dichloromethylsilane, trichloroethylene-based silane, boron trichloride and hexamethyldisilazane, wherein the molar ratio of the raw materials is 10: (3-7): (3-7): (30-51). The light-cured resin system for additive manufacturing of the SiBCN ceramic can complete printing forming of high-precision polyborosilazane through DLP 3D printing equipment, the SiBCN ceramic prepared through pyrolysis generates equal-proportion shrinkage of about 50%, the sintered ceramic is free of warping and cracking, the original printed basic shape is maintained, and preparation of the SiBCN ceramic in a complex shape is achieved.

The invention relates to the technical field of high polymer materials, and discloses ablation-resistant metal modified polyborosilazane resin as well as a preparation method and application thereof. The method comprises the following steps: (1) in an argon or nitrogen atmosphere, dropwise adding a part of hexamethyldisilazane into a solution containing metal chloride, and carrying out a first contact reaction to obtain an intermediate compound I; (2) in an argon or nitrogen atmosphere, dropwise adding the other part of hexamethyldisilazane into a mixed solution of boron trichloride and methyl dichlorosilane, and then mixing with the intermediate compound I to carry out a second contact reaction, so as to obtain an intermediate compound II; and (3) in an argon or nitrogen atmosphere, carrying out segmented heating curing treatment on the intermediate compound II to obtain the ablation-resistant metal modified polyborosilazane resin. According to the method, refractory metal elements are introduced into a polymerization system in situ in the form of a prefabricated metal silazane precursor, the polyborosilazane resin with uniformly distributed metal is successfully prepared, the high temperature resistance and ablation resistance of the material are remarkably improved, the controllability of the reaction process is high, and the industrial application prospect is good.

This invention discloses a method for the continuous production of lithium difluorooxalate borate using a microchannel reactor, comprising the following steps: lithium fluoride is added to a solvent, the temperature is maintained at 10-20°C, and the mixture is stirred until homogeneous to obtain a lithium fluoride solution; the lithium fluoride solution, boron trifluoride gas, oxalic acid, boron trichloride gas, and silicon tetrachloride are respectively introduced into the microchannel reactor; the gas at the top is absorbed by a multi-stage falling film to form a hydrochloric acid solution, and the silicon tetrafluoride gas reacts with the hydrofluoric acid solution to generate hexafluorosilicic acid; the solution leaving the bottom of the reactor is degassed by negative pressure heating, cooled for crystallization, filtered, and dried to obtain a qualified product. The reaction of this invention occurs continuously in the microchannel reactor, which, compared to intermittent reactions, significantly reduces energy consumption and raw material consumption for the same production capacity, eliminates many intermediate equipment, and lowers investment costs.

The invention discloses a preparation method and application of a novel boron-nitrogen heterocyclic boron compound. The preparation method comprises the following steps: taking o-amino styrene, o-aminobiphenyl or derivatives thereof as raw materials, carrying out ring closing reaction under the action of boron trichloride to generate chlorine / bromoborane, and then further reacting the chlorine / bromoborane under the action of metal sodium, thereby generating the target boron-nitrogen heterocyclic biboron compound. The synthesis method is simple and convenient to operate, the basic structural unit of the synthesized diboron compound is the 2, 1-boron nitrogen heterocyclic ring, the unique structure endows the diboron compound with special reaction activity, a series of compounds containing the 2, 1-boron nitrogen heterocyclic ring can be further efficiently prepared from the diboron compound, and particularly, the diboron compound has broad application prospects in the field of organic functional materials. The method has great potential application value, and is expected to provide new material selection and technical support for the development of related fields.

The application relates to a preparation method of a high-wear-resistance tungsten boride coating and belongs to the technical field of wear-resistant material preparation. By using a chemical vapor deposition technology, a pure tungsten coating with a thickness of about 29.1 microns is first prepared on a tungsten base, then a low-temperature solid-phase boronizing technology is used to convert part of the pure tungsten coating into a tungsten boride coating, and thus the surface hardness and wear resistance of the material are improved. Compared with direct chemical vapor deposition of tungsten boride on a metal surface, the method can avoid using the high-risk boron trichloride gas, and can effectively control the coating thickness and the microstructure. The coating preparation process can be applied to the surface strengthening modification of various metal materials, and has strong practical application value.

To provide atomic layer etching of molybdenum that is used in a variety of applications in semiconductor processing, such as word line isolation in 3D NAND fabrication, etch molybdenum in a highly controllable manner by performing one or more etching cycles.SOLUTION: In a molybdenum etching method, each etching cycle includes exposing a substrate having a molybdenum layer to an oxygen-containing reactant to form molybdenum oxide, followed by treatment with boron trichloride to convert the molybdenum oxide to a volatile molybdic oxychloride, and then treating the substrate with a fluorine-containing reactant to remove the boron oxide formed in the previous reaction from the substrate surface. In some embodiments, the method is performed in the absence of a plasma to obtain a substantially isotropic etch.SELECTED DRAWING: Figure 1

The application belongs to the field of new energy, and discloses a synthesis method of lithium tetrafluoroborate, which comprises the following steps: step 1: adding lithium halide into a non-aqueous organic solvent, and introducing boron trichloride to obtain a solution containing lithium haloborate; and step 2: introducing hydrogen fluoride into the solution obtained in step 1 to obtain a solution containing lithium tetrafluoroborate. The method is synthesized by using a solvent method, and any available lithium halide and boron trichloride are used to react to obtain an intermediate product, and then the intermediate product is fluorinated to obtain lithium tetrafluoroborate, and various lithium halides can be selected to realize the scheme of the application, the raw materials are rich in selectivity, and the production cost is significantly reduced.