Synthesis method capable of improving solid-phase synthesis silicon carbide discharge rate and silicon carbide synthesis furnace

Abstract

The invention relates to the technical field of silicon carbide synthesis, and discloses a synthesis method capable of improving solid-phase synthesis silicon carbide discharge rate and a silicon carbide synthesis furnace, the synthesis method comprises the following steps: crushing, screening, cleaning and drying a silicon carbide product block to obtain silicon carbide powder; the preparation method comprises the following steps: mixing silicon carbide powder, carbon powder, silicon powder and polytetrafluoroethylene powder by utilizing a high-energy ball milling technology and an ultrasonic-assisted mixing technology to obtain a mixed raw material; uniformly paving the mixed raw material in a graphite crucible, putting the graphite crucible into a silicon carbide synthesis furnace, and carrying out solid-phase synthesis of silicon carbide on the basis of optimal synthesis parameters output by a parameter optimization algorithm. According to the method, the production cost of solid-phase synthesis of silicon carbide can be effectively reduced, the yield of silicon carbide is remarkably improved, energy consumption and raw material waste in the production process are reduced, and the quality and purity of the silicon carbide product can be improved by accurately controlling synthesis parameters.

Description

Technical Field

[0001] The invention relates to the technical field of silicon carbide synthesis, and in particular to a synthesis method and a silicon carbide synthesis furnace capable of improving the output rate of solid-phase synthesized silicon carbide. Background Art

[0002] With the continuous progress of the semiconductor industry, silicon carbide has received widespread attention from the industry. As an outstanding representative of the third-generation semiconductor materials, silicon carbide has demonstrated many outstanding properties that surpass traditional silicon materials, including significantly higher energy band width, electron migration speed, voltage tolerance, thermal conductivity and high temperature stability. These characteristics enable it to show unparalleled performance advantages under extreme electronic equipment application conditions such as high temperature, high voltage and high frequency. With the growing demand for silicon carbide, the demand for basic raw materials necessary for the production of silicon carbide is also on the rise.

[0003] In this case, silicon carbide is not only regarded as an indispensable key material in high-performance electronic devices, but its application in new energy vehicles, solar power generation, high-efficiency power transmission systems, etc., has further promoted its interest in research and development. Therefore, with the continuous expansion of demand for third-generation semiconductor materials, optimizing the production process of silicon carbide, reducing costs, and improving efficiency and output have become important directions for industry research.

[0004] At present, the traditional synthesis methods of silicon carbide mainly cover two categories: gas phase synthesis and solid phase reaction synthesis. Gas phase synthesis, such as chemical vapor deposition (CVD), can produce high-purity and high-quality silicon carbide crystals, but its complex process requirements, high energy consumption and limited its ability to be mass-produced. Solid phase reaction synthesis, as a more traditional method, produces silicon carbide by directly heating a mixture of silicon and carbon sources. Although it is easy to operate and has low cost, its low yield, high energy consumption, and strict requirements for raw material mixing uniformity and reaction control all limit its efficiency in industrial-scale applications.

[0005] Therefore, the present invention provides a synthesis method and a silicon carbide synthesis furnace which can improve the output rate of solid phase synthesis of silicon carbide. Summary of the invention

[0006] In view of the problems in the related art, the present invention proposes a synthesis method and a silicon carbide synthesis furnace that can improve the output rate of solid-phase synthesis of silicon carbide, so as to overcome the above-mentioned technical problems existing in the existing related art.

[0007] To this end, the specific technical solution adopted by the present invention is as follows: According to one aspect of the present invention, there is provided a synthesis method capable of improving the yield of solid phase synthesized silicon carbide, comprising the following steps: S1. Obtaining a silicon carbide product block synthesized in advance by solid phase synthesis, and crushing, screening, washing and drying the silicon carbide product block to obtain silicon carbide powder; S2. Using high-energy ball milling technology combined with ultrasonic-assisted mixing technology to mix silicon carbide powder, carbon powder, silicon powder and polytetrafluoroethylene powder to obtain a mixed raw material; S3, evenly laying the mixed raw materials in a graphite crucible, and placing the graphite crucible in a silicon carbide synthesis furnace, and performing solid phase synthesis of silicon carbide based on the optimal synthesis parameters output by the parameter optimization algorithm; The optimal synthesis parameters include reaction temperature, heating rate, reaction pressure and holding time parameters that maximize the yield while satisfying product quality and preset costs.

[0008] Furthermore, the process of mixing silicon carbide powder, carbon powder, silicon powder and polytetrafluoroethylene powder using high-energy ball milling technology combined with ultrasonic-assisted mixing technology to obtain a mixed raw material includes the following steps: S21, weighing silicon carbide powder, carbon powder, silicon powder and polytetrafluoroethylene powder of preset weights and proportions, and performing preliminary mixing in a mixing container; S22, transferring the preliminarily mixed powder to a high-energy ball mill, and ball milling the preliminarily mixed powder using the ball milling medium in the ball mill; S23, evenly distributing the ball-milled powder in an ultrasonic processor container, adding a dispersion medium and mixing evenly, and treating the suspension with ultrasound; S24. After the ultrasonic-assisted mixing is completed, the mixture is dried and the dispersion medium in the mixture is removed to obtain a mixed raw material.

[0009] Furthermore, the mixed raw materials are evenly laid in a graphite crucible, and the graphite crucible is placed in a silicon carbide synthesis furnace, and solid-phase synthesis of silicon carbide based on the optimal synthesis parameters output by the parameter optimization algorithm includes the following steps: S31, evenly laying the mixed raw materials in a graphite crucible with a fluorinated graphite lining layer, and placing the graphite crucible in a silicon carbide synthesis furnace; S32, using a parameter optimization algorithm in combination with input parameters of the mixed raw materials to predict the corresponding optimal synthesis parameters, wherein the input parameters of the mixed raw materials include particle size and weight data of silicon carbide powder, carbon powder, silicon powder and polytetrafluoroethylene powder; S33, setting the reaction temperature, reaction pressure, heating rate and holding time of the silicon carbide synthesis furnace according to the predicted optimal synthesis parameters; S34, starting the silicon carbide synthesis furnace, introducing a mixed gas of hydrogen and inert gas during the heating process, and extracting the gas in the silicon carbide synthesis furnace after a preset time; S35, refilling the silicon carbide synthesis furnace with inert gas until the reaction pressure is reached, gradually heating the furnace to the reaction temperature according to the heating rate, and performing insulation treatment according to the set insulation time; S36. After the heat preservation is completed, the mixture is naturally cooled to room temperature, and then the graphite crucible is taken out to obtain synthesized silicon carbide.

[0010] Furthermore, a fluorinated graphite lining is provided in the graphite crucible, and the thickness of the fluorinated graphite lining is 3-8 mm.

[0011] Furthermore, the step of evenly laying the mixed raw material in a graphite crucible with a fluorinated graphite lining layer and placing the graphite crucible in a silicon carbide synthesis furnace comprises the following steps: S311, setting a fluorinated graphite lining layer in a graphite crucible, and precalculating the weight and laying thickness of the mixed raw material according to the size and shape of the graphite crucible; S312, using a layered paving method to evenly lay the mixed raw materials in the graphite crucible, and using a tapping method after each layer of paving is completed to improve the paving uniformity of the mixed raw materials; S313, placing the graphite crucible covered with the mixed raw materials into a silicon carbide synthesis furnace.

[0012] Furthermore, the method of using a parameter optimization algorithm to predict the optimal synthesis parameters corresponding to the input parameters of the mixed raw materials includes the following steps: S321, obtaining historical data of solid phase synthesis of silicon carbide in a database, and constructing a performance index evaluation model based on the historical data of solid phase synthesis of silicon carbide and performing training; S322. Use a parameter optimization algorithm combined with a performance indicator evaluation model to find the best synthesis parameters corresponding to the input parameters in the parameter space.

[0013] Furthermore, the acquisition of historical data of solid phase synthesis of silicon carbide in the database, and the construction and training of a performance index evaluation model based on the historical data of solid phase synthesis of silicon carbide include the following steps: S3211. Obtain historical data of solid phase synthesis of silicon carbide in the database and perform preprocessing, wherein the historical data includes the particle size and weight data of silicon carbide powder, carbon powder, silicon powder, and polytetrafluoroethylene powder, as well as the reaction temperature, heating rate, reaction pressure and holding time data during synthesis, and the yield and quality of silicon carbide products; S3212, using the obtained particle size and weight data of silicon carbide powder, carbon powder, silicon powder, and polytetrafluoroethylene powder, as well as the reaction temperature, heating rate, reaction pressure, and holding time data during synthesis as input parameters, and using the yield and quality of the silicon carbide product as output parameters; S3213. Construct a training set and a test set based on the input parameters and the output parameters, and use the training set and the test set to train and test the performance indicator evaluation model to obtain a trained performance indicator evaluation model.

[0014] Furthermore, the method of using the parameter optimization algorithm in combination with the performance index evaluation model to search for the best synthesis parameters corresponding to the input parameters in the parameter space includes the following steps: S3221. Define the optimization goal and construct an objective function to quantify the optimization goal, wherein the optimization goal is to maximize the yield while satisfying product quality and preset cost; S3222, defining a value range of synthesis parameters, and randomly generating a set of initial solutions within the value range of the synthesis parameters, and evaluating the performance of the initial solutions using a performance index evaluation model, wherein the synthesis parameters include reaction temperature, heating rate, reaction pressure, and holding time data in a solid phase synthesis process of silicon carbide; S3223, generating a new solution set based on the selection, crossover and mutation operations of the genetic algorithm, and using the performance indicator evaluation model to perform performance evaluation on the newly generated solution, and updating the new solution set according to the evaluation results; S3224. Repeat S3223 until a preset number of iterations is reached or a preset performance standard is reached, and the optimal solution is selected from the current solution set to obtain the optimal synthesis parameters corresponding to the input parameters.

[0015] Furthermore, the method of using the performance indicator evaluation model to perform performance evaluation on the newly generated solution and updating the new solution set according to the evaluation result includes the following steps: The newly generated solution is decoded to obtain new synthesis parameters, and the trained performance index evaluation model is used to combine the particle size and weight data of silicon carbide powder, carbon powder, silicon powder, and polytetrafluoroethylene powder to output the corresponding yield and quality of silicon carbide products to obtain performance evaluation results; The fitness value of each solution is calculated based on the results of the performance evaluation, and the new solution set is updated according to the calculation results of the fitness value.

[0016] According to another aspect of the present invention, a silicon carbide synthesis furnace is provided, including a synthesis furnace, wherein a plurality of groups of heating components are arranged on the inner side walls of the synthesis furnace, and each group of heating components is composed of a plurality of heating coils, each group of heating components is connected to an induction power supply through a wire, and the induction power supply is electrically connected to a control cabinet, a graphite crucible is arranged inside the synthesis furnace, and a fluorinated graphite lining layer is arranged on the inner wall of the graphite crucible.

[0017] The beneficial effects of the present invention are: 1) The present invention can not only significantly improve the uniformity and reaction efficiency of the reaction raw materials, promote the efficiency of the solid phase synthesis reaction, and increase the output rate of silicon carbide by combining high-energy ball milling technology and ultrasonic assisted mixing technology, but also provide precise control for the solid phase synthesis of silicon carbide by using the optimal synthesis parameters (reaction temperature, heating rate, reaction pressure and holding time) predicted by the parameter optimization algorithm, thereby maximizing the yield while meeting the product quality and preset cost, and effectively improving the output rate of silicon carbide. Compared with traditional technologies, the present invention can not only effectively reduce the production cost of solid phase synthesis of silicon carbide, significantly improve the yield of silicon carbide, and reduce energy consumption and raw material waste in the production process, but also improve the quality and purity of silicon carbide products by precisely controlling the synthesis parameters.

[0018] 2) By adding silicon carbide powder and polytetrafluoroethylene powder to the mixed raw materials, the mixing uniformity of the raw materials can be improved under the action of polytetrafluoroethylene powder, and the volatilization of silicon can be reduced under the action of silicon carbide powder, thereby increasing the output rate of solid phase synthesis. In addition, the use of graphite crucibles lined with fluorinated graphite not only improves the corrosion resistance and service life of the crucible, but also optimizes the reaction conditions, reduces the introduction of impurities, and improves the quality of the product. By introducing a parameter optimization algorithm, based on historical data and performance index evaluation models, the optimal synthesis parameters are scientifically predicted and selected, which not only optimizes the reaction conditions, improves the quality and yield of the product, but also reduces costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 is a flow chart of a synthesis method capable of improving the output rate of solid phase synthesis silicon carbide according to an embodiment of the present invention; Figure 2 Schematic diagram of the structure of a silicon carbide synthesis furnace according to an embodiment of the present invention.

[0021] In the figure: 1. Synthesis furnace; 2. Heating component; 3. Induction power supply; 4. Control cabinet; 5. Graphite crucible; 6. Fluorinated graphite lining layer. DETAILED DESCRIPTION

[0022] To further illustrate each embodiment, the present invention provides drawings, which are part of the disclosure of the present invention and are mainly used to illustrate the embodiments and can be used in conjunction with the relevant descriptions in the specification to explain the operating principles of the embodiments. With reference to these contents, ordinary technicians in the field should be able to understand other possible implementations and advantages of the present invention. The components in the figures are not drawn to scale, and similar component symbols are generally used to represent similar components.

[0023] According to an embodiment of the present invention, a synthesis method and a silicon carbide synthesis furnace are provided, which can improve the output rate of solid-phase synthesized silicon carbide.

[0024] The present invention is further described with reference to the accompanying drawings and specific embodiments. Figure 1 As shown, according to one embodiment of the present invention, a synthesis method for improving the output rate of solid phase synthesis of silicon carbide is provided, comprising the following steps: S1. Obtaining a silicon carbide product block synthesized in advance by solid phase synthesis, and crushing, screening, washing and drying the silicon carbide product block to obtain silicon carbide powder; Specifically, obtaining a silicon carbide product block synthesized in advance in a solid phase, and crushing, screening, cleaning and drying the silicon carbide product block to obtain silicon carbide powder includes the following steps: 1) Crushing Crushing equipment selection: Selecting appropriate crushing equipment, such as jaw crusher, ball mill or hammer crusher, depends on the required powder particle size and output.

[0025] Crushing process: Put the silicon carbide product block into the crushing equipment and crush it to the initially set particle size range. The crushing process needs to be carried out in several stages to gradually reduce the particle size.

[0026] 2) Screening Screening Equipment Selection: Use appropriate screening equipment, such as vibrating screens or cyclone classifiers, to classify according to particle size.

[0027] Screening process: The crushed silicon carbide powder is passed through a screening device to separate powders of different particle sizes. Coarser particles need to be re-crushed to ensure that all powders meet the required particle size specifications.

[0028] 3) Cleaning Cleaning solvent selection: According to the characteristics of silicon carbide powder and subsequent applications, select appropriate cleaning solvents, such as deionized water, alcohol or other special solvents.

[0029] Cleaning process: Soak the screened silicon carbide powder in the cleaning solvent and gently stir to remove surface impurities and residual production by-products. The cleaned powder needs to be thoroughly filtered or centrifuged to remove the solvent.

[0030] 4) Drying Drying Equipment Selection: Selecting appropriate drying equipment, such as hot air drying oven, vacuum drying oven or spray dryer, depends on the required drying speed and powder characteristics.

[0031] Drying process: The cleaned and filtered silicon carbide powder is placed in a drying device and dried to the required humidity level. Drying conditions (such as temperature and time) need to be tailored according to the characteristics of the powder.

[0032] This series of physical processing steps ensures that the obtained silicon carbide powder has a consistent particle size distribution, as well as being clean, dry, and suitable for subsequent applications or further processing. The specific parameters of each step (such as equipment selection, temperature setting, processing time, etc.) need to be optimized according to the specific material properties and target applications.

[0033] S2. Using high-energy ball milling technology combined with ultrasonic-assisted mixing technology to mix silicon carbide powder, carbon powder, silicon powder and polytetrafluoroethylene powder to obtain a mixed raw material; The method of mixing silicon carbide powder, carbon powder, silicon powder and polytetrafluoroethylene powder by high-energy ball milling technology combined with ultrasonic-assisted mixing technology to obtain a mixed raw material includes the following steps: S21, weighing silicon carbide powder, carbon powder, silicon powder and polytetrafluoroethylene powder of preset weight and proportion, and performing preliminary mixing treatment using a mixing container (such as a V-type mixer, a blade mixer, etc.) to achieve rough uniform mixing; S22, transferring the preliminarily mixed powder to a high-energy ball mill, and ball milling the preliminarily mixed powder using the ball milling medium in the ball mill; Specifically, the preliminary mixed powder is first transferred to a high-energy ball mill, and an appropriate amount of ball milling media, such as carbide balls, zirconia balls, etc., is added to the ball mill; then the ball milling parameters are set, such as ball milling speed, time, mass ratio of balls to powder, etc. These parameters need to be optimized according to the experimental purpose and material properties; finally, the ball mill is started for ball milling treatment. High-energy ball milling can effectively increase the fineness of the powder, improve the mixing uniformity, and promote the reaction activity of the material through mechanical force.

[0034] S23, evenly distributing the ball-milled powder in an ultrasonic processor container, adding a dispersion medium and mixing evenly, and treating the suspension with ultrasound; Specifically, the powder after ball milling is first subjected to ultrasonic-assisted mixing, and the powder is mixed with an appropriate amount of dispersion medium (such as alcohol, deionized water, etc.) to facilitate ultrasonic treatment; then an ultrasonic mixer is used to treat the suspension (a suspension refers to a mixture formed by uniformly dispersing solid powder raw materials in a liquid medium). The high-intensity sound waves generated by ultrasound can further refine the powder particle size, break up particle agglomerations, and achieve a higher degree of mixing uniformity; the time and power of ultrasonic treatment need to be optimized according to the material properties and expected effects.

[0035] S24. After the ultrasonic-assisted mixing is completed, the mixture is dried and the dispersion medium in the mixture is removed to obtain a mixed raw material.

[0036] Specifically, after completing the ultrasonic-assisted mixing, the mixture needs to be dried to remove the dispersion medium; the dried powder may need to be sieved to remove any insufficiently refined particles or agglomerates; a slight ball milling or other form of post-processing may also be performed as needed to ensure the uniformity and activity of the final mixture.

[0037] Through step S2, highly uniformly mixed raw materials can be obtained, which is of great significance for the subsequent solid phase synthesis of silicon carbide and helps to improve the synthesis efficiency and the performance of the final product.

[0038] S3. Evenly spread the mixed raw materials in a graphite crucible, and place the graphite crucible in a silicon carbide synthesis furnace, and perform solid phase synthesis of silicon carbide based on the optimal synthesis parameters output by a parameter optimization algorithm; wherein the optimal synthesis parameters include reaction temperature, heating rate, reaction pressure and holding time parameters that maximize the yield while satisfying product quality and a preset cost.

[0039] Specifically, the mixed raw materials are evenly laid in a graphite crucible, and the graphite crucible is placed in a silicon carbide synthesis furnace, and solid-phase synthesis of silicon carbide based on the optimal synthesis parameters output by the parameter optimization algorithm includes the following steps: S31. Evenly spread the mixed raw materials in a graphite crucible with a fluorinated graphite lining layer, and place the graphite crucible in a silicon carbide synthesis furnace.

[0040] Specifically, the process of evenly laying the mixed raw materials in a graphite crucible with a fluorinated graphite lining layer and placing the graphite crucible in a silicon carbide synthesis furnace comprises the following steps: S311, setting a fluorinated graphite lining layer in a graphite crucible, wherein the thickness of the fluorinated graphite lining is 3-8 mm, and pre-calculating the weight and laying thickness of the mixed raw material according to the size and shape of the graphite crucible; S312. Use the layered laying method to evenly lay the mixed raw materials in the graphite crucible, and use the tapping method to improve the laying uniformity of the mixed raw materials after each layer is laid; Specifically, during the laying process, it is carried out in layers. After each layer is laid, it is gently compacted to ensure good contact between layers, while avoiding the generation of voids or bubbles; control the thickness of the laying layer to ensure that each layer can be evenly heated during the synthesis process, and avoid inconsistent reaction rates between the central part and the edge part.

[0041] S313. Put the graphite crucible with the laid mixed raw materials into the silicon carbide synthesis furnace.

[0042] S32. Use the parameter optimization algorithm to predict the corresponding optimal synthesis parameters in combination with the input parameters of the mixed raw materials. Among them, the input parameters of the mixed raw materials include the particle size and weight data of silicon carbide powder, carbon powder, silicon powder and polytetrafluoroethylene powder; Specifically, the use of the parameter optimization algorithm to predict the corresponding optimal synthesis parameters in combination with the input parameters of the mixed raw materials includes the following steps: S321. Obtain the historical data of solid-phase synthesis of silicon carbide in the database, and construct and train a performance index evaluation model based on the historical data of solid-phase synthesis of silicon carbide; The obtaining of the historical data of solid-phase synthesis of silicon carbide in the database and the construction and training of a performance index evaluation model based on the historical data of solid-phase synthesis of silicon carbide include the following steps: S3211. Obtain the historical data of solid-phase synthesis of silicon carbide in the database and perform preprocessing (that is, clean and preprocess the collected data, including removing outliers, filling in missing values, data standardization, etc., to ensure data quality and prepare for subsequent model training). Among them, the historical data includes the particle size and weight data of silicon carbide powder, carbon powder, silicon powder, polytetrafluoroethylene powder, as well as the reaction temperature, heating rate, reaction pressure and holding time data during synthesis, and the yield and quality of silicon carbide products; S3212. Use the particle size and weight data of silicon carbide powder, carbon powder, silicon powder, polytetrafluoroethylene powder and the reaction temperature, heating rate, reaction pressure and holding time data during synthesis as input parameters, and use the yield and quality of silicon carbide products as output parameters; S3213. Construct a training set and a test set based on the input parameters and output parameters (a common ratio is 70% training data and 30% test data), and use the training set and the test set to train and test the performance index evaluation model (in this embodiment, this performance index evaluation model is a neural network model) to obtain a trained performance index evaluation model.

[0043] In addition, the test set data can be used to evaluate the performance of the model. Common evaluation indicators include accuracy, precision, recall, F1 score, etc.; analyze the results of model prediction, identify possible problems with the model (such as overfitting or underfitting), and based on the results of model evaluation, return to the steps of data preprocessing, feature selection, model selection or parameter tuning to further optimize the model.

[0044] S322. Use a parameter optimization algorithm combined with a performance indicator evaluation model to find the best synthesis parameters corresponding to the input parameters in the parameter space.

[0045] The method of using the parameter optimization algorithm in combination with the performance index evaluation model to find the best synthesis parameters corresponding to the input parameters in the parameter space comprises the following steps: S3221. Define the optimization goal and construct an objective function to quantify the optimization goal, wherein the optimization goal is to maximize the yield while satisfying product quality and preset cost; S3222, defining a value range of synthesis parameters, and randomly generating a set of initial solutions within the value range of the synthesis parameters, and evaluating the performance of the initial solutions using a performance index evaluation model, wherein the synthesis parameters include reaction temperature, heating rate, reaction pressure, and holding time data in a solid phase synthesis process of silicon carbide; S3223, generating a new solution set based on the selection, crossover and mutation operations of the genetic algorithm, and using the performance indicator evaluation model to perform performance evaluation on the newly generated solution, and updating the new solution set according to the evaluation results; The method of using the performance indicator evaluation model to evaluate the performance of the newly generated solution and updating the new solution set according to the evaluation result comprises the following steps: The newly generated solution (usually expressed in the form of a string or array) in the genetic algorithm is decoded to obtain new synthesis parameters. The trained performance indicator evaluation model is combined with the particle size and weight data of silicon carbide powder, carbon powder, silicon powder, and polytetrafluoroethylene powder to output the corresponding yield and quality of silicon carbide products to obtain performance evaluation results. The fitness value of each solution is calculated based on the results of the performance evaluation. The fitness value reflects the performance of the solution on the objective function, that is, how "suitable" it is for the current optimization goal, and the new solution set is updated according to the calculation results of the fitness value. The solution update rules are as follows: Selection Mechanism: Based on the calculated fitness values, some selection mechanism (such as roulette selection, tournament selection, etc.) is used to decide which solutions will be retained and become part of the next generation.

[0046] Update strategies: including direct replacement (the new generation completely replaces the old generation), elite retention (retaining a portion of the best performance solutions), or other strategies.

[0047] S3224. Repeat S3223 until a preset number of iterations is reached or a preset performance standard is reached, and the optimal solution is selected from the current solution set to obtain the optimal synthesis parameters corresponding to the input parameters.

[0048] S33, setting the reaction temperature, reaction pressure, heating rate and holding time of the silicon carbide synthesis furnace according to the predicted optimal synthesis parameters; S34, starting the silicon carbide synthesis furnace, introducing a mixed gas of hydrogen and inert gas during the heating process, and extracting the gas in the silicon carbide synthesis furnace after a preset time; Specifically, before or at the beginning of the heating of the synthesis furnace, a pre-prepared mixed gas of hydrogen and inert gas (such as argon) is introduced, which helps to create a reducing and / or inert environment and reduce possible oxidation reactions. A flow meter or similar device is used to accurately control the inflow rate of the gas to ensure that the gas mixing ratio and flow rate meet the requirements of the synthesis process.

[0049] S35, refilling the silicon carbide synthesis furnace with inert gas until the reaction pressure is reached, gradually heating the furnace to the reaction temperature according to the heating rate, and performing insulation treatment according to the set insulation time; Specifically, during the silicon carbide synthesis process, the synthesis furnace is refilled with inert gas until the required reaction pressure is reached, and then the temperature is gradually raised to the reaction temperature according to the predetermined heating rate, and the insulation treatment is performed according to the set insulation time. This is a key step to ensure the silicon carbide synthesis efficiency and product quality. The following describes this process in detail: 1) Inert gas filling Gas Selection: Inert gases, such as argon, are often used in the SiC synthesis process to provide a non-reactive environment and prevent oxidation of the material.

[0050] Filling inert gas: Start the gas supply system and fill the synthesis furnace with inert gas until the predetermined reaction pressure is reached. Use a pressure gauge to monitor the pressure in the furnace in real time to ensure that it reaches the required standard for synthesis.

[0051] 2) Heating process Heating rate: The heating rate in the furnace is set by the control system to ensure that it meets the predicted optimal parameters. The appropriate heating rate helps to ensure uniform temperature in the furnace and avoid local overheating or incomplete reaction of the material.

[0052] Reaction temperature: According to the preset program, the furnace gradually heats up to the required reaction temperature. This temperature needs to be precisely set according to the specific requirements of silicon carbide synthesis.

[0053] 3) Insulation treatment Insulation time setting: After reaching the reaction temperature, maintain the temperature unchanged and carry out insulation treatment according to the previously set insulation time. This period of time is the key stage to ensure that the chemical reaction is fully carried out.

[0054] Monitor the reaction: During the holding period, continue to monitor the pressure and temperature in the furnace to ensure that they remain within the set parameters. This helps to ensure the smooth progress of the reaction and ultimately obtain high-quality silicon carbide products.

[0055] S36, naturally cooling to room temperature after the heat preservation is completed, then taking out the graphite crucible to obtain synthesized silicon carbide, specifically comprising: Cooling: After the insulation treatment is completed, gradually reduce the furnace temperature to room temperature according to the operating manual and safety guidelines. The cooling rate needs to be controlled to avoid material stress caused by rapid cooling.

[0056] Pressure release: Gradually reduce the pressure in the furnace at the right time until it returns to atmospheric pressure. Ensure smooth pressure release throughout the process to prevent safety problems caused by rapid pressure changes.

[0057] Sampling and analysis: After the furnace has cooled to a safe temperature, samples are taken out for subsequent quality inspection and analysis, including evaluation of indicators such as purity, crystal structure and particle size.

[0058] In order to better understand the technical solution of solid phase synthesis of silicon carbide based on the optimal synthesis parameters output by the parameter optimization algorithm in step S3, an example is given below: Suppose our goal is to synthesize high-purity, high-performance silicon carbide powder on an industrial scale. First, prepare a mixed raw material, including fine silicon carbide powder, pure carbon powder, high-purity silicon powder, and a small amount of polytetrafluoroethylene powder as a sintering aid. In order to ensure uniformity and complete reaction during the solid phase reaction, the selection and pretreatment of the raw materials are crucial. The steps include: 1) Raw material preparation and laying: First, calculate the weight ratio of various powders required, assuming that 1 kg of silicon carbide needs to be synthesized. Based on previous experiments and theoretical calculations, the optimal ratio of silicon carbide powder, carbon powder, silicon powder and polytetrafluoroethylene powder was determined. A 3-8mm thick fluorinated graphite lining layer is set in a graphite crucible of preset size and shape to prevent the material from reacting with the crucible at high temperature. The mixed raw materials are evenly laid in the crucible by layering. After each layer is laid, it is gently compacted by tapping to ensure the uniformity and good contact of the mixed raw materials.

[0059] 2) Parameter optimization and prediction: Using historical data and performance indicator evaluation models (such as neural network models), the reaction temperature, heating rate, reaction pressure and holding time in the solid phase synthesis process of silicon carbide are optimized. Here, the optimization goal is to maximize the yield while ensuring product quality and controlling costs. After iterations of parameter optimization algorithms (such as genetic algorithms), a set of optimal synthesis parameters is obtained. For example, the reaction temperature is set to 2200°C, the heating rate is 5°C / min, the reaction pressure is 1.5×101.325kPa, and the holding time is 4 hours.

[0060] 3) Synthesis process: Place the graphite crucible with the mixed raw materials into the silicon carbide synthesis furnace, and set the synthesis parameters of the synthesis furnace according to the optimized parameters. At the beginning of the temperature rise, a mixed gas of hydrogen and inert gas (such as argon) is introduced to create a reducing and inert environment. The temperature is gradually raised to the reaction temperature at the set heating rate, and then the insulation treatment is carried out according to the set insulation time. After the insulation is completed, let the furnace cool naturally to room temperature, then take out the graphite crucible to obtain the synthesized silicon carbide powder.

[0061] Conclusion: High-quality silicon carbide powder was successfully synthesized by precisely controlling various parameters in the synthesis process. This process not only improves the yield, but also ensures the quality of the product. This example illustrates how to systematically achieve the synthesis of high-performance silicon carbide materials in industrial production through parameter optimization and fine control of raw material preparation and synthesis steps.

[0062] According to another embodiment of the present invention, Figure 2 As shown, a silicon carbide synthesis furnace is provided, including a synthesis furnace 1, wherein the inner side wall of the synthesis furnace 1 is provided with a plurality of groups of heating components 2, and each group of the heating components 2 is composed of a plurality of heating coils, and each group of the heating components 2 is connected to an induction power supply 3 through a wire, and in specific application, a plurality of induction power supplies 3 can independently control the induction coils for heating, so that the temperature at different positions in the synthesis furnace 1 can be independently adjusted, and the induction power supplies 3 are electrically connected to a control cabinet 4, and a graphite crucible 5 is provided inside the synthesis furnace 1, and a fluorinated graphite lining layer 6 is provided on the inner wall of the graphite crucible 5.

[0063] In summary, with the help of the above technical scheme of the present invention, the present invention can not only significantly improve the uniformity and reaction efficiency of the reaction raw materials by combining high-energy ball milling technology and ultrasonic-assisted mixing technology, promote the efficiency of solid-phase synthesis reaction, and improve the output rate of silicon carbide, but also can use the optimal synthesis parameters (reaction temperature, heating rate, reaction pressure and holding time) predicted by the parameter optimization algorithm to provide precise control for the solid-phase synthesis of silicon carbide, so as to maximize the yield while meeting the product quality and preset cost, and effectively improve the output rate of silicon carbide. Compared with traditional technology, the present invention can not only effectively reduce the production cost of solid-phase synthesis of silicon carbide, significantly improve the yield of silicon carbide, and reduce energy consumption and raw material waste in the production process, but also improve the quality and purity of silicon carbide products by precisely controlling the synthesis parameters.

[0064] At the same time, by adding silicon carbide powder and polytetrafluoroethylene powder to the mixed raw materials, the mixing uniformity of the raw materials can be improved under the action of polytetrafluoroethylene powder, and the volatilization of silicon can be reduced under the action of silicon carbide powder, thereby improving the discharge rate of solid phase synthesis. In addition, the use of graphite crucibles lined with fluorinated graphite not only improves the corrosion resistance and service life of the crucible, but also optimizes the reaction conditions, reduces the introduction of impurities, and improves the quality of the product. By introducing a parameter optimization algorithm, based on historical data and performance index evaluation models, the optimal synthesis parameters are scientifically predicted and selected, which not only optimizes the reaction conditions, improves the quality and yield of the product, but also reduces costs.

[0065] In the present invention, unless otherwise clearly stipulated and limited, the terms such as "installation", "setting", "connection", "fixation" and "screw-on" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements. Unless otherwise clearly defined, ordinary technicians in this field can understand the specific meanings of the above terms in the present invention according to the specific circumstances.

[0066] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A synthesis method capable of improving the yield of solid phase synthesized silicon carbide, characterized in that: The following steps are involved: S1. Obtaining a silicon carbide product block synthesized in advance by solid phase synthesis, and crushing, screening, washing and drying the silicon carbide product block to obtain silicon carbide powder; S2. Using high-energy ball milling technology combined with ultrasonic-assisted mixing technology to mix silicon carbide powder, carbon powder, silicon powder and polytetrafluoroethylene powder to obtain a mixed raw material; S3, evenly laying the mixed raw materials in a graphite crucible, and placing the graphite crucible in a silicon carbide synthesis furnace, and performing solid phase synthesis of silicon carbide based on the optimal synthesis parameters output by the parameter optimization algorithm; The optimal synthesis parameters include reaction temperature, heating rate, reaction pressure and holding time parameters that maximize the yield while satisfying product quality and preset costs.

2. The synthesis method for improving the yield of solid phase synthesized silicon carbide according to claim 1, characterized in that: The method of mixing silicon carbide powder, carbon powder, silicon powder and polytetrafluoroethylene powder by using high-energy ball milling technology combined with ultrasonic-assisted mixing technology to obtain a mixed raw material includes the following steps: S21, weighing silicon carbide powder, carbon powder, silicon powder and polytetrafluoroethylene powder of preset weights and proportions, and performing preliminary mixing in a mixing container; S22, transferring the preliminarily mixed powder to a high-energy ball mill, and ball milling the preliminarily mixed powder using the ball milling medium in the ball mill; S23, evenly distributing the ball-milled powder in an ultrasonic processor container, adding a dispersion medium and mixing evenly, and treating the suspension with ultrasound; S24. After the ultrasonic-assisted mixing is completed, the mixture is dried and the dispersion medium in the mixture is removed to obtain a mixed raw material.

3. The synthesis method for improving the yield of solid phase synthesized silicon carbide according to claim 1, characterized in that: The mixed raw materials are evenly laid in a graphite crucible, and the graphite crucible is placed in a silicon carbide synthesis furnace, and solid-phase synthesis of silicon carbide based on the optimal synthesis parameters output by the parameter optimization algorithm comprises the following steps: S31, evenly laying the mixed raw materials in a graphite crucible with a fluorinated graphite lining layer, and placing the graphite crucible in a silicon carbide synthesis furnace; S32, using a parameter optimization algorithm in combination with input parameters of the mixed raw materials to predict the corresponding optimal synthesis parameters, wherein the input parameters of the mixed raw materials include particle size and weight data of silicon carbide powder, carbon powder, silicon powder and polytetrafluoroethylene powder; S33, setting the reaction temperature, reaction pressure, heating rate and holding time of the silicon carbide synthesis furnace according to the predicted optimal synthesis parameters; S34, starting the silicon carbide synthesis furnace, introducing a mixed gas of hydrogen and inert gas during the heating process, and extracting the gas in the silicon carbide synthesis furnace after a preset time; S35, refilling the silicon carbide synthesis furnace with inert gas until the reaction pressure is reached, gradually heating the furnace to the reaction temperature according to the heating rate, and performing insulation treatment according to the set insulation time; S36. After the heat preservation is completed, the mixture is naturally cooled to room temperature, and then the graphite crucible is taken out to obtain synthesized silicon carbide.

4. The synthesis method for improving the yield of solid phase synthesized silicon carbide according to claim 3, characterized in that: The graphite crucible is provided with a fluorinated graphite lining, and the thickness of the fluorinated graphite lining is 3-8 mm.

5. The synthesis method for improving the yield of solid phase synthesized silicon carbide according to claim 3, characterized in that: The process of evenly laying the mixed raw materials in a graphite crucible with a fluorinated graphite lining layer and placing the graphite crucible in a silicon carbide synthesis furnace comprises the following steps: S311, setting a fluorinated graphite lining layer in a graphite crucible, and precalculating the weight and laying thickness of the mixed raw material according to the size and shape of the graphite crucible; S312, using a layered paving method to evenly lay the mixed raw materials in the graphite crucible, and using a tapping method after each layer of paving is completed to improve the paving uniformity of the mixed raw materials; S313, placing the graphite crucible covered with the mixed raw materials into a silicon carbide synthesis furnace.

6. The synthesis method for improving the yield of solid phase synthesized silicon carbide according to claim 3, characterized in that: The method of using a parameter optimization algorithm to predict the optimal synthesis parameters corresponding to the input parameters of the mixed raw materials comprises the following steps: S321, obtaining historical data of solid phase synthesis of silicon carbide in a database, and constructing a performance index evaluation model based on the historical data of solid phase synthesis of silicon carbide and performing training; S322. Use a parameter optimization algorithm combined with a performance indicator evaluation model to find the best synthesis parameters corresponding to the input parameters in the parameter space.

7. The synthesis method for improving the yield of solid phase synthesized silicon carbide according to claim 6, characterized in that: The method of obtaining the historical data of solid phase synthesized silicon carbide in the database, and constructing and training a performance index evaluation model based on the historical data of solid phase synthesized silicon carbide includes the following steps: S3211. Obtain historical data of solid phase synthesis of silicon carbide in the database and perform preprocessing, wherein the historical data includes the particle size and weight data of silicon carbide powder, carbon powder, silicon powder, and polytetrafluoroethylene powder, as well as the reaction temperature, heating rate, reaction pressure and holding time data during synthesis, and the yield and quality of silicon carbide products; S3212, using the obtained particle size and weight data of silicon carbide powder, carbon powder, silicon powder, and polytetrafluoroethylene powder, as well as the reaction temperature, heating rate, reaction pressure, and holding time data during synthesis as input parameters, and using the yield and quality of the silicon carbide product as output parameters; S3213. Construct a training set and a test set based on the input parameters and the output parameters, and use the training set and the test set to train and test the performance indicator evaluation model to obtain a trained performance indicator evaluation model.

8. The synthesis method for improving the yield of solid phase synthesized silicon carbide according to claim 7, characterized in that: The method of using the parameter optimization algorithm in combination with the performance index evaluation model to find the best synthesis parameters corresponding to the input parameters in the parameter space comprises the following steps: S3221. Define the optimization goal and construct an objective function to quantify the optimization goal, wherein the optimization goal is to maximize the yield while satisfying product quality and preset cost; S3222, defining a value range of synthesis parameters, and randomly generating a set of initial solutions within the value range of the synthesis parameters, and evaluating the performance of the initial solutions using a performance index evaluation model, wherein the synthesis parameters include reaction temperature, heating rate, reaction pressure, and holding time data in a solid phase synthesis process of silicon carbide; S3223, generating a new solution set based on the selection, crossover and mutation operations of the genetic algorithm, and using the performance indicator evaluation model to perform performance evaluation on the newly generated solution, and updating the new solution set according to the evaluation results; S3224. Repeat S3223 until a preset number of iterations is reached or a preset performance standard is reached, and the optimal solution is selected from the current solution set to obtain the optimal synthesis parameters corresponding to the input parameters.

9. The synthesis method for improving the yield of solid phase synthesized silicon carbide according to claim 8, characterized in that: The method of using the performance indicator evaluation model to evaluate the performance of the newly generated solution and updating the new solution set according to the evaluation result comprises the following steps: The newly generated solution is decoded to obtain new synthesis parameters, and the trained performance index evaluation model is used to combine the particle size and weight data of silicon carbide powder, carbon powder, silicon powder, and polytetrafluoroethylene powder to output the corresponding yield and quality of silicon carbide products to obtain performance evaluation results; The fitness value of each solution is calculated based on the results of the performance evaluation, and the new solution set is updated according to the calculation results of the fitness value.

10. A silicon carbide synthesis furnace, used for realizing the synthesis of silicon carbide in the synthesis method capable of improving the output rate of solid phase synthesis silicon carbide as claimed in any one of claims 1 to 9, characterized in that: The silicon carbide synthesis furnace comprises a synthesis furnace (1), wherein a plurality of groups of heating components (2) are arranged on the inner side wall of the synthesis furnace (1), and each group of the heating components (2) is composed of a plurality of heating coils, each group of the heating components (2) is connected to an induction power supply (3) via a wire, and the induction power supply (3) is electrically connected to a control cabinet (4), and a graphite crucible (5) is arranged inside the synthesis furnace (1), and a fluorinated graphite lining layer (6) is arranged on the inner wall of the graphite crucible (5).

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