A synthesis method and silicon carbide synthesis furnace that can improve the yield of solid-phase silicon carbide synthesis

Abstract

This invention relates to the field of silicon carbide synthesis technology, and discloses a synthesis method and a silicon carbide synthesis furnace that can improve the yield of solid-phase silicon carbide synthesis. The synthesis method includes the following steps: crushing, sieving, washing, and drying silicon carbide product blocks to obtain silicon carbide powder; 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; uniformly spreading the mixed raw material in a graphite crucible, placing the graphite crucible in a silicon carbide synthesis furnace, and performing solid-phase silicon carbide synthesis based on the optimal synthesis parameters output by a parameter optimization algorithm. This invention can not only effectively reduce the production cost of solid-phase silicon carbide synthesis, significantly improve the yield of silicon carbide, and reduce energy consumption and raw material waste during the production process, but also improve the quality and purity of silicon carbide products by precisely controlling the synthesis parameters.

Description

Technical Field

[0001] This invention relates to the field of silicon carbide synthesis technology, and more specifically, to a synthesis method and a silicon carbide synthesis furnace that can improve the yield of solid-phase silicon carbide synthesis. Background Technology

[0002] With the continuous advancement of the semiconductor industry, silicon carbide has gained widespread attention. As an outstanding representative of third-generation semiconductor materials, silicon carbide exhibits several superior properties compared to traditional silicon materials, including significantly higher bandgap, electron mobility, voltage withstand capability, thermal conductivity, and high-temperature stability. These characteristics enable it to demonstrate unparalleled performance advantages in extreme electronic device applications such as high temperature, high voltage, and high frequency. Along with the increasing demand for silicon carbide, the demand for the essential raw materials necessary for its production is also on the rise.

[0003] In this context, silicon carbide is not only considered an indispensable key material in high-performance electronic devices, but its applications in new energy vehicles, solar power generation, and high-efficiency power transmission systems have further fueled interest in its research and development. Therefore, with the continued expansion of demand for third-generation semiconductor materials, optimizing the silicon carbide production process, reducing costs, and improving efficiency and yield have become important research directions for the industry.

[0004] Currently, traditional methods for synthesizing silicon carbide mainly fall into 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 limitations on large-scale production restrict its capabilities. Solid-phase reaction synthesis, as a more traditional method, produces silicon carbide by directly heating a mixture of silicon and a carbon source. Although it is simple to operate and has lower costs, its low yield, high energy consumption, and strict requirements for raw material mixing uniformity and reaction control all limit its efficiency for industrial-scale applications.

[0005] Therefore, the present invention provides a synthesis method and a silicon carbide synthesis furnace that can improve the yield of solid-phase silicon carbide synthesis. Summary of the Invention

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

[0007] Therefore, the specific technical solution adopted by the present invention is as follows:

[0008] According to one aspect of the present invention, a synthesis method for improving the yield of solid-phase silicon carbide is provided, comprising the following steps:

[0009] S1. Obtain the pre-solid-phase synthesized silicon carbide product block, and crush, sieve, wash and dry the silicon carbide product block to obtain silicon carbide powder.

[0010] S2. High-energy ball milling technology combined with ultrasonic-assisted mixing technology is used to mix silicon carbide powder, carbon powder, silicon powder and polytetrafluoroethylene powder to obtain mixed raw materials;

[0011] S3. Spread the mixed raw materials evenly in the graphite crucible, and place the graphite crucible in the silicon carbide synthesis furnace. Perform solid-phase synthesis of silicon carbide based on the optimal synthesis parameters output by the parameter optimization algorithm.

[0012] The optimal synthesis parameters include the reaction temperature, heating rate, reaction pressure, and holding time, which maximize the yield while meeting product quality and preset costs.

[0013] 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 the mixed raw material includes the following steps:

[0014] S21. Weigh the silicon carbide powder, carbon powder, silicon powder and polytetrafluoroethylene powder according to the preset weight and proportion, and perform preliminary mixing treatment using a mixing container.

[0015] S22. Transfer the pre-mixed powder to a high-energy ball mill and use the grinding media in the ball mill to ball mill the pre-mixed powder.

[0016] S23. The powder after ball milling is evenly dispersed in the container of the ultrasonic processor, and a dispersion medium is added and mixed evenly. The suspension is then treated with ultrasound.

[0017] S24. After ultrasonic-assisted mixing is completed, the mixture is dried and the dispersion medium in the mixture is removed to obtain the mixed raw material.

[0018] Furthermore, the step of uniformly spreading 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, includes the following steps:

[0019] S31. Spread the mixed raw materials evenly in a graphite crucible with a fluorinated graphite liner, and place the graphite crucible in a silicon carbide synthesis furnace.

[0020] S32. Predict the optimal synthesis parameters corresponding to the mixed raw materials by using a parameter optimization algorithm in combination with the input parameters of the mixed raw materials, wherein 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.

[0021] S33. Set the reaction temperature, reaction pressure, heating rate and holding time of the silicon carbide synthesis furnace according to the predicted optimal synthesis parameters;

[0022] S34. Start the silicon carbide synthesis furnace, introduce a mixture of hydrogen and inert gas during the heating process, and extract the gas from the silicon carbide synthesis furnace after a preset time.

[0023] S35. Inert gas is introduced into the silicon carbide synthesis furnace again until the reaction pressure is reached. The temperature is gradually increased to the reaction temperature according to the heating rate, and the temperature is maintained according to the set holding time.

[0024] S36. After the heat preservation is completed, the mixture is naturally cooled to room temperature. Then the graphite crucible is removed to obtain the synthesized silicon carbide.

[0025] Furthermore, the graphite crucible is provided with a fluorinated graphite liner, and the thickness of the fluorinated graphite liner is 3-8 mm.

[0026] Furthermore, the step of uniformly spreading the mixed raw materials in a graphite crucible with a fluorinated graphite liner and placing the graphite crucible into a silicon carbide synthesis furnace includes the following steps:

[0027] S311. A fluorinated graphite liner is installed in the graphite crucible, and the weight and thickness of the mixed raw materials are calculated in advance according to the size and shape of the graphite crucible.

[0028] S312. The mixed raw materials are evenly spread in the graphite crucible using a layered spreading method, and the uniformity of the mixed raw materials is improved by tapping after each layer is laid.

[0029] S313. Place the graphite crucible containing the mixed raw materials into the silicon carbide synthesis furnace.

[0030] Furthermore, the step of using a parameter optimization algorithm to predict the corresponding optimal synthesis parameters based on the input parameters of the mixed raw materials includes the following steps:

[0031] S321. Obtain historical data on solid-phase synthesis of silicon carbide from the database, and construct and train a performance index evaluation model based on the historical data on solid-phase synthesis of silicon carbide.

[0032] S322. Use parameter optimization algorithms combined with performance index evaluation models to find the optimal synthetic parameters corresponding to the input parameters in the parameter space.

[0033] Furthermore, the step of obtaining historical data on solid-phase silicon carbide synthesis from the database, and constructing and training a performance evaluation model based on this historical data, includes the following steps:

[0034] S3211. Obtain historical data on solid-phase synthesis of silicon carbide from the database and perform preprocessing. The historical data includes particle size and weight data of silicon carbide powder, carbon powder, silicon powder, and polytetrafluoroethylene powder, as well as reaction temperature, heating rate, reaction pressure, and holding time data during synthesis, and the yield and quality of silicon carbide products.

[0035] S3212. 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 during synthesis, are used as input parameters, and the yield and mass of silicon carbide products are used as output parameters.

[0036] S3213. Construct training and testing sets based on input and output parameters, and use the training and testing sets to train and test the performance evaluation model to obtain a trained performance evaluation model.

[0037] Furthermore, the step of using a parameter optimization algorithm combined with a performance index evaluation model to find the optimal synthesized parameters corresponding to the input parameters in the parameter space includes the following steps:

[0038] S3221. Define the optimization objective and construct an objective function to quantify the optimization objective, wherein the optimization objective is to maximize the yield while meeting product quality and preset cost.

[0039] S3222. Define the range of values ​​for the synthesis parameters, and randomly generate a set of initial solutions within the range of values ​​for the synthesis parameters. Use the performance index evaluation model to evaluate the performance of the initial solutions. The synthesis parameters include the reaction temperature, heating rate, reaction pressure and holding time data in the solid-state synthesis of silicon carbide.

[0040] S3223. Generate a new solution set based on selection, crossover and mutation operations of genetic algorithm, evaluate the performance of the newly generated solution using performance index evaluation model, and update the new solution set according to the evaluation results;

[0041] S3224. Repeat S3223 until the preset number of iterations or the preset performance standard is reached, and select the optimal solution from the current solution set to obtain the best synthesis parameters corresponding to the input parameters.

[0042] Furthermore, the process of evaluating the performance of the newly generated solution using a performance index evaluation model and updating the new solution set based on the evaluation results includes the following steps:

[0043] The newly generated solution is decoded to obtain new synthesis parameters. The trained performance index evaluation model is used in conjunction 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 product, and the performance evaluation results are obtained.

[0044] The fitness value of each solution is calculated based on the performance evaluation results, and the new solution set is updated according to the fitness value calculation results.

[0045] According to another aspect of the present invention, a silicon carbide synthesis furnace is provided, comprising a synthesis furnace, wherein a plurality of heating components are provided on the inner sidewall of the synthesis furnace, and each heating component is composed of a plurality of heating coils, each heating component is connected to an induction power supply via a wire, and the induction power supply is electrically connected to a control cabinet, and a graphite crucible is provided inside the synthesis furnace, wherein a fluorinated graphite lining layer is provided on the inner wall of the graphite crucible.

[0046] The beneficial effects of this invention are as follows:

[0047] 1) This invention not only significantly improves the uniformity and reaction efficiency of reactants by combining high-energy ball milling and ultrasonic-assisted mixing technologies, thereby promoting the efficiency of solid-state synthesis and increasing the yield of silicon carbide, but also provides precise control over the solid-state synthesis of silicon carbide by utilizing optimal synthesis parameters (reaction temperature, heating rate, reaction pressure, and holding time) predicted by parameter optimization algorithms. This maximizes yield while meeting product quality and preset costs, effectively increasing the silicon carbide yield. Compared to traditional technologies, this invention not only effectively reduces the production cost of solid-state silicon carbide synthesis, significantly increases silicon carbide yield, and reduces energy consumption and raw material waste during production, but also improves the quality and purity of silicon carbide products through precise control of synthesis parameters.

[0048] 2) By adding silicon carbide powder and polytetrafluoroethylene (PTFE) powder to the mixed raw materials, the mixing uniformity of the raw materials is improved by the PTFE powder, and the volatilization of silicon is reduced by the silicon carbide powder, thus increasing the yield of solid-phase synthesis. Furthermore, using a graphite crucible with a fluorinated graphite liner not only improves the crucible's corrosion resistance and service life but also optimizes reaction conditions, reduces the introduction of impurities, and improves product quality. 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 reaction conditions and improves product quality and yield but also reduces costs. Attached Figure Description

[0049] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0050] Figure 1 This is a flowchart of a synthesis method for improving the yield of solid-phase silicon carbide according to an embodiment of the present invention;

[0051] Figure 2 This is a schematic diagram of the structure of a silicon carbide synthesis furnace according to an embodiment of the present invention.

[0052] In the picture:

[0053] 1. Synthesis furnace; 2. Heating components; 3. Induction power supply; 4. Control cabinet; 5. Graphite crucible; 6. Fluorograph lining. Detailed Implementation

[0054] To further illustrate the various embodiments, the present invention provides accompanying drawings, which are part of the disclosure of the present invention. These drawings 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 drawings, those skilled in the art should be able to understand other possible implementation methods and the advantages of the present invention. The components in the drawings are not drawn to scale, and similar component symbols are generally used to represent similar components.

[0055] According to embodiments of the present invention, a synthesis method and a silicon carbide synthesis furnace that can improve the yield of solid-phase silicon carbide synthesis are provided.

[0056] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments, such as... Figure 1 As shown, according to an embodiment of the present invention, a synthesis method for improving the yield of solid-phase silicon carbide is provided, comprising the following steps:

[0057] S1. Obtain the pre-solid-phase synthesized silicon carbide product block, and crush, sieve, wash and dry the silicon carbide product block to obtain silicon carbide powder.

[0058] Specifically, the process of obtaining a pre-synthesized solid-state silicon carbide product block and then pulverizing, sieving, washing, and drying the silicon carbide product block to obtain silicon carbide powder includes the following steps:

[0059] 1) Crushing

[0060] Selection of crushing equipment: The choice of appropriate crushing equipment, such as jaw crusher, ball mill or hammer crusher, depends on the required powder particle size and output.

[0061] Crushing process: The silicon carbide product blocks are fed into the crushing equipment and crushed to the initially set particle size range. The crushing process needs to be carried out in several stages to gradually reduce the particle size.

[0062] 2) Screening

[0063] Selection of screening equipment: Use appropriate screening equipment, such as vibrating screens or cyclone classifiers, to classify according to particle size.

[0064] Screening process: The pulverized silicon carbide powder is passed through a screening device to separate powders of different particle sizes. Coarser particles need to be re-pulverized to ensure that all powders meet the required particle size specifications.

[0065] 3) Cleaning

[0066] Cleaning solvent selection: Select an appropriate cleaning solvent, such as deionized water, alcohol or other special solvents, based on the characteristics of silicon carbide powder and subsequent applications.

[0067] Cleaning process: Immerse the sieved silicon carbide powder in a cleaning solvent and gently stir to remove surface impurities and residual production byproducts. The cleaned powder must be thoroughly filtered or centrifuged to remove the solvent.

[0068] 4) Drying

[0069] Selection of drying equipment: The choice of appropriate drying equipment, such as hot air drying box, vacuum drying box or spray dryer, depends on the required drying speed and powder characteristics.

[0070] 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 customized according to the characteristics of the powder.

[0071] This series of physical processing steps ensures that the resulting silicon carbide powder has a consistent particle size distribution, is clean and dry, and is 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 application.

[0072] S2. High-energy ball milling technology combined with ultrasonic-assisted mixing technology is used to mix silicon carbide powder, carbon powder, silicon powder and polytetrafluoroethylene powder to obtain mixed raw materials;

[0073] 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:

[0074] S21. Weigh out the silicon carbide powder, carbon powder, silicon powder and polytetrafluoroethylene powder in the preset weight and proportion, and use a mixing container (such as a V-type mixer, blade mixer, etc.) to perform preliminary mixing treatment, the purpose of which is to achieve rough uniform mixing.

[0075] S22. Transfer the pre-mixed powder to a high-energy ball mill and use the grinding media in the ball mill to ball mill the pre-mixed powder.

[0076] Specifically, the pre-mixed powder is first transferred to a high-energy ball mill, and an appropriate amount of grinding media, such as cemented carbide balls or zirconia balls, is added to the ball mill. Then, the ball milling parameters are set, such as the ball milling speed, time, and the mass ratio of balls to powder. These parameters need to be optimized according to the experimental purpose and material characteristics. Finally, the ball mill is started to perform ball milling. High-energy ball milling can effectively improve the fineness of the powder, improve the mixing uniformity, and promote the reactivity of the material through mechanical force.

[0077] S23. The powder after ball milling is evenly dispersed in the container of the ultrasonic processor, and a dispersion medium is added and mixed evenly. The suspension is then treated with ultrasound.

[0078] Specifically, the powder after ball milling is first mixed with ultrasonic-assisted mixing, where an appropriate amount of dispersion medium (such as alcohol, deionized water, etc.) is mixed to facilitate ultrasonic treatment. Then, an ultrasonic mixer is used to treat the suspension (a suspension is a mixture in which solid powder raw materials are uniformly dispersed in a liquid medium). The high-intensity sound waves generated by the ultrasonic waves can further refine the powder particle size, break up particle agglomeration, and achieve a higher degree of mixing uniformity. The time and power of the ultrasonic treatment need to be optimized according to the material characteristics and expected results.

[0079] S24. After ultrasonic-assisted mixing is completed, the mixture is dried and the dispersion medium in the mixture is removed to obtain the mixed raw material.

[0080] Specifically, after ultrasonic-assisted mixing is completed, 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 light ball milling or other form of post-processing may also be performed as needed to ensure the homogeneity and activity of the final mixture.

[0081] The S2 step yields a highly uniformly mixed raw material, which is of great significance for subsequent solid-phase synthesis of silicon carbide, helping to improve synthesis efficiency and the performance of the final product.

[0082] S3. The mixed raw materials are evenly spread in a graphite crucible, and the graphite crucible is placed in a silicon carbide synthesis furnace. Solid-state synthesis of silicon carbide is carried out based on the optimal synthesis parameters output by the parameter optimization algorithm. The optimal synthesis parameters include the reaction temperature, heating rate, reaction pressure and holding time parameters that maximize the yield while meeting product quality and preset cost.

[0083] Specifically, the process of uniformly spreading the mixed raw materials in a graphite crucible, 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 a parameter optimization algorithm includes the following steps:

[0084] S31. The mixed raw materials are evenly spread in a graphite crucible with a fluorinated graphite liner, and the graphite crucible is placed in a silicon carbide synthesis furnace.

[0085] Specifically, the step of uniformly spreading the mixed raw materials in a graphite crucible with a fluorinated graphite liner and placing the graphite crucible into a silicon carbide synthesis furnace includes the following steps:

[0086] S311. A fluorinated graphite liner is provided in a graphite crucible, and the thickness of the fluorinated graphite liner is 3-8 mm. The weight of the mixed raw materials and the thickness of the liner are calculated in advance according to the size and shape of the graphite crucible.

[0087] S312. The mixed raw materials are evenly spread in the graphite crucible using a layered spreading method, and the uniformity of the mixed raw materials is improved by tapping after each layer is laid.

[0088] Specifically, the process is carried out in layers, with each layer being gently compacted after it is laid to ensure good contact between the layers and to avoid voids or air bubbles. The thickness of the layers is controlled to ensure that each layer is heated evenly during the synthesis process, thus avoiding inconsistent reaction rates between the center and the edges.

[0089] S313. Place the graphite crucible containing the mixed raw materials into the silicon carbide synthesis furnace.

[0090] S32. Predict the optimal synthesis parameters corresponding to the mixed raw materials by using a parameter optimization algorithm in combination with the input parameters of the mixed raw materials, wherein 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.

[0091] Specifically, the step of using a parameter optimization algorithm to predict the corresponding optimal synthesis parameters based on the input parameters of the mixed raw materials includes the following steps:

[0092] S321. Obtain historical data on solid-phase synthesis of silicon carbide from the database, and construct and train a performance index evaluation model based on the historical data on solid-phase synthesis of silicon carbide.

[0093] The process of obtaining historical data on solid-phase silicon carbide synthesis from the database and constructing and training a performance evaluation model based on this data includes the following steps:

[0094] S3211. Obtain historical data on solid-phase synthesis of silicon carbide from the database and perform preprocessing (i.e., clean and preprocess the collected data, including removing outliers, filling missing values, and standardizing the data to ensure data quality and prepare for subsequent model training). The historical data includes particle size and weight data of silicon carbide powder, carbon powder, silicon powder, and polytetrafluoroethylene powder, as well as reaction temperature, heating rate, reaction pressure, and holding time data during synthesis, and the yield and quality of silicon carbide products.

[0095] S3212. 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 during synthesis, are used as input parameters, and the yield and mass of silicon carbide products are used as output parameters.

[0096] S3213. Construct training and testing sets based on input and output parameters (a common ratio is 70% training data and 30% testing data), and use the training and testing sets to train and test the performance evaluation model (in this embodiment, the performance evaluation model is a neural network model) to obtain a trained performance evaluation model.

[0097] In addition, test set data can be used to evaluate the performance of the model. Common evaluation metrics include accuracy, precision, recall, F1 score, etc. Analyze the model's prediction results, identify potential problems with the model (such as overfitting or underfitting), and based on the model evaluation results, return to the steps of data preprocessing, feature selection, model selection, or parameter tuning to further optimize the model.

[0098] S322. Use parameter optimization algorithms combined with performance index evaluation models to find the optimal synthetic parameters corresponding to the input parameters in the parameter space.

[0099] The process of finding the optimal synthesized parameters corresponding to the input parameters in the parameter space using a parameter optimization algorithm combined with a performance index evaluation model includes the following steps:

[0100] S3221. Define the optimization objective and construct an objective function to quantify the optimization objective, wherein the optimization objective is to maximize the yield while meeting product quality and preset cost.

[0101] S3222. Define the range of values ​​for the synthesis parameters, and randomly generate a set of initial solutions within the range of values ​​for the synthesis parameters. Use the performance index evaluation model to evaluate the performance of the initial solutions. The synthesis parameters include the reaction temperature, heating rate, reaction pressure and holding time data in the solid-state synthesis of silicon carbide.

[0102] S3223. Generate a new solution set based on selection, crossover and mutation operations of genetic algorithm, evaluate the performance of the newly generated solution using performance index evaluation model, and update the new solution set according to the evaluation results;

[0103] The process of evaluating the performance of the newly generated solution using a performance index evaluation model and updating the new solution set based on the evaluation results includes the following steps:

[0104] The newly generated solutions (usually represented as strings or arrays) in the genetic algorithm are decoded to obtain new synthesis parameters. A trained performance evaluation model, combined with particle size and weight data of silicon carbide powder, carbon powder, silicon powder, and polytetrafluoroethylene powder, outputs the corresponding yield and quality of the silicon carbide product, yielding performance evaluation results. Based on the performance evaluation results, the fitness value of each solution is calculated. The fitness value reflects the solution's performance on the objective function, i.e., how "fit" it is to the current optimization objective. The new solution set is updated based on the calculated fitness values. The solution update rules are as follows:

[0105] Selection mechanism: Based on the calculated fitness value, a selection mechanism (such as roulette wheel selection, tournament selection, etc.) is used to determine which solutions will be retained and become part of the next generation.

[0106] Update strategies include direct replacement (the new generation completely replaces the old generation), elite retention (retaining a portion of the best-performing solutions), or other strategies.

[0107] S3224. Repeat S3223 until the preset number of iterations or the preset performance standard is reached, and select the optimal solution from the current solution set to obtain the best synthesis parameters corresponding to the input parameters.

[0108] S33. Set the reaction temperature, reaction pressure, heating rate and holding time of the silicon carbide synthesis furnace according to the predicted optimal synthesis parameters;

[0109] S34. Start the silicon carbide synthesis furnace, introduce a mixture of hydrogen and inert gas during the heating process, and extract the gas from the silicon carbide synthesis furnace after a preset time.

[0110] Specifically, before or at the initial stage of heating the synthesis furnace, a pre-mixed mixture of hydrogen and an inert gas (such as argon) is introduced. This mixture helps create a reducing and / or inert environment, reducing potential oxidation reactions. A flow meter or similar device is used to precisely control the gas inflow rate, ensuring that the gas mixing ratio and flow rate meet the requirements of the synthesis process.

[0111] S35. Inert gas is introduced into the silicon carbide synthesis furnace again until the reaction pressure is reached. The temperature is gradually increased to the reaction temperature according to the heating rate, and the temperature is maintained according to the set holding time.

[0112] Specifically, in the silicon carbide synthesis process, the inert gas is re-introduced into the synthesis furnace until the required reaction pressure is reached. Then, the temperature is gradually increased to the reaction temperature according to a predetermined heating rate, and a holding time is performed according to a set time. This is a key step to ensure the efficiency of silicon carbide synthesis and product quality. This process is described in detail below:

[0113] 1) Inert gas filling

[0114] Gas selection: Inert gases, such as argon, are often used in the synthesis of silicon carbide to provide a non-reactive environment and prevent the material from oxidizing.

[0115] Inert gas charging: Start the gas supply system and charge the synthesis furnace with inert gas until the predetermined reaction pressure is reached. Use a pressure gauge to monitor the furnace pressure in real time to ensure that it meets the standards required for synthesis.

[0116] 2) Heating process

[0117] Heating rate: The heating rate inside the furnace is set by the control system to ensure it meets the predicted optimal parameters. An appropriate heating rate helps ensure uniform temperature inside the furnace and avoids localized overheating or incomplete reaction of the material.

[0118] 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.

[0119] 3) Thermal insulation treatment

[0120] Holding time setting: After reaching the reaction temperature, maintain this temperature and hold it for the previously set time. This period is crucial for ensuring the complete chemical reaction.

[0121] Reaction monitoring: During the holding period, continue to monitor the pressure and temperature inside the furnace to ensure they remain within the set parameter range. This helps ensure the smooth progress of the reaction and ultimately obtains high-quality silicon carbide products.

[0122] S36. After the heat treatment is completed, allow it to cool naturally to room temperature, then remove the graphite crucible to obtain the synthesized silicon carbide, specifically including:

[0123] Cooling: After the heat preservation treatment is completed, the furnace temperature is gradually reduced to room temperature according to the operation manual and safety guidelines. The cooling rate needs to be controlled to avoid material stress caused by rapid cooling.

[0124] Pressure release: Gradually reduce the furnace pressure at appropriate times until it returns to atmospheric pressure. Ensure a smooth pressure release throughout the process to prevent safety issues caused by rapid pressure changes.

[0125] Sampling and analysis: After the furnace body cools to a safe temperature, the sample is taken out for subsequent quality inspection and analysis, including the evaluation of indicators such as purity, crystal structure and particle size.

[0126] To better understand the technical solution for solid-phase synthesis of silicon carbide based on the optimal synthesis parameters output by the parameter optimization algorithm in step S3, the following example is provided:

[0127] Suppose our goal is to synthesize high-purity, high-performance silicon carbide powder on an industrial scale. First, prepare a mixture of raw materials, including fine silicon carbide powder, pure carbon powder, high-purity silicon powder, and a small amount of polytetrafluoroethylene powder as a sintering aid. To ensure uniformity and complete reaction during the solid-state reaction, the selection and pretreatment of raw materials are crucial. This includes the following steps:

[0128] 1) Raw Material Preparation and Laying: First, the required weight ratios of various powders were calculated, assuming the synthesis of 1 kg of silicon carbide. Based on previous experiments and theoretical calculations, the optimal ratio of silicon carbide powder, carbon powder, silicon powder, and polytetrafluoroethylene powder was determined. A 3-8 mm thick fluorinated graphite liner was placed in a graphite crucible of a predetermined size and shape to prevent the material from reacting with the crucible at high temperatures. The mixed raw materials were evenly laid in the crucible using a layered laying method. After each layer was laid, it was gently compacted using a tapping method to ensure the uniformity and good contact of the mixed raw materials.

[0129] 2) Parameter Optimization and Prediction: Historical data and performance evaluation models (such as neural network models) were used to optimize parameters such as reaction temperature, heating rate, reaction pressure, and holding time in the silicon carbide solid-state synthesis process. The optimization objective was to maximize yield while ensuring product quality and controlling costs. Through iterative optimization using a parameter optimization algorithm (such as a genetic algorithm), a set of optimal synthesis parameters was obtained. For example, the reaction temperature was set to 2200°C, the heating rate to 5°C / min, the reaction pressure to 1.5 × 10¹³²⁵ kPa, and the holding time to 4 hours.

[0130] 3) Synthesis Process: A graphite crucible containing the mixed raw materials is placed in a silicon carbide synthesis furnace, and the synthesis parameters of the furnace are set according to the optimized parameters. In the initial stage of heating, a mixture of hydrogen and an inert gas (such as argon) is introduced to create a reducing and inert environment. The temperature is gradually increased to the reaction temperature according to the set heating rate, and then held at that temperature for the set time. After the holding time is complete, the furnace is allowed to cool naturally to room temperature, and then the graphite crucible is removed to obtain the synthesized silicon carbide powder.

[0131] Conclusion: High-quality silicon carbide powder was successfully synthesized by precisely controlling various parameters in the synthesis process. This process not only improved the yield but also ensured product quality. This example illustrates how to systematically synthesize high-performance silicon carbide materials in industrial production through parameter optimization and precise control of raw material preparation and synthesis steps.

[0132] According to another embodiment of the invention, such as Figure 2 As shown, a silicon carbide synthesis furnace is provided, including a synthesis furnace 1. The inner sidewall of the synthesis furnace 1 is provided with several sets of heating components 2, and each set of heating components 2 is composed of several heating coils. Each set of heating components 2 is connected to an induction power supply 3 through a wire. In specific applications, multiple induction power supplies 3 can independently control the induction coils to heat, thereby independently adjusting the temperature at different positions in the synthesis furnace 1. The induction power supplies 3 are all electrically connected to a control cabinet 4. A graphite crucible 5 is provided inside the synthesis furnace 1, and the inner wall of the graphite crucible 5 is provided with a fluorinated graphite lining layer 6.

[0133] In summary, by utilizing the above-mentioned technical solutions of this invention, the present invention not only significantly improves the uniformity and reaction efficiency of the reaction raw materials by combining high-energy ball milling technology and ultrasonic-assisted mixing technology, thereby promoting the efficiency of solid-phase synthesis reaction and increasing the yield of silicon carbide, but also provides precise control for the solid-phase synthesis of silicon carbide by utilizing the optimal synthesis parameters (reaction temperature, heating rate, reaction pressure, and holding time) predicted by parameter optimization algorithms. This allows for maximizing yield while meeting product quality and preset costs, effectively increasing the yield of silicon carbide. Compared to traditional technologies, this invention not only effectively reduces the production cost of solid-phase silicon carbide synthesis, significantly increases the yield of silicon carbide, and reduces energy consumption and raw material waste during the production process, but also improves the quality and purity of silicon carbide products through precise control of synthesis parameters.

[0134] Meanwhile, by adding silicon carbide powder and polytetrafluoroethylene (PTFE) powder to the mixed raw materials, the mixing uniformity of the raw materials is improved by the PTFE powder, and the volatilization of silicon is reduced by the silicon carbide powder, thus increasing the yield of solid-phase synthesis. Furthermore, using a graphite crucible with a fluorinated graphite liner not only improves the crucible's corrosion resistance and service life but also optimizes reaction conditions, reduces the introduction of impurities, and improves product quality. 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 reaction conditions and improves product quality and yield but also reduces costs.

[0135] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "setting," "connection," "fixing," "screw connection," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal connection of two components or the interaction between two components. Unless otherwise explicitly limited, those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0136] 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 principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A synthesis method that can improve the yield of solid-phase silicon carbide synthesis, characterized in that, Includes the following steps: S1. Obtain the pre-solid-phase synthesized silicon carbide product block, and crush, sieve, wash and dry the silicon carbide product block to obtain silicon carbide powder. S2. High-energy ball milling technology combined with ultrasonic-assisted mixing technology is used to mix silicon carbide powder, carbon powder, silicon powder and polytetrafluoroethylene powder to obtain mixed raw materials; S3. Spread the mixed raw materials evenly in the graphite crucible, and place the graphite crucible in the silicon carbide synthesis furnace. Perform solid-phase synthesis of silicon carbide based on the optimal synthesis parameters output by the parameter optimization algorithm. The optimal synthesis parameters include the reaction temperature, heating rate, reaction pressure, and holding time that maximize the yield while meeting product quality and preset costs. The process of uniformly spreading the mixed raw materials in a graphite crucible, 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 a parameter optimization algorithm includes the following steps: S31. Spread the mixed raw materials evenly in a graphite crucible with a fluorinated graphite liner, and place the graphite crucible in a silicon carbide synthesis furnace. S32. Predict the optimal synthesis parameters corresponding to the mixed raw materials by using a parameter optimization algorithm in combination with the input parameters of the mixed raw materials, wherein 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. S33. Set the reaction temperature, reaction pressure, heating rate and holding time of the silicon carbide synthesis furnace according to the predicted optimal synthesis parameters; S34. Start the silicon carbide synthesis furnace, introduce a mixture of hydrogen and inert gas during the heating process, and extract the gas from the silicon carbide synthesis furnace after a preset time. S35. Inert gas is introduced into the silicon carbide synthesis furnace again until the reaction pressure is reached. The temperature is gradually increased to the reaction temperature according to the heating rate, and the temperature is maintained according to the set holding time. S36. After the heat preservation is completed, the mixture is naturally cooled to room temperature. Then the graphite crucible is removed to obtain the synthesized silicon carbide.

2. The synthesis method for improving the yield of solid-phase silicon carbide according to claim 1, characterized in that, 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. Weigh the silicon carbide powder, carbon powder, silicon powder and polytetrafluoroethylene powder according to the preset weight and proportion, and perform preliminary mixing treatment using a mixing container. S22. Transfer the pre-mixed powder to a high-energy ball mill and use the grinding media in the ball mill to ball mill the pre-mixed powder. S23. The powder after ball milling is evenly dispersed in the container of the ultrasonic processor, and a dispersion medium is added and mixed evenly. The suspension is then treated with ultrasound. S24. After ultrasonic-assisted mixing is completed, the mixture is dried and the dispersion medium in the mixture is removed to obtain the mixed raw material.

3. The synthesis method for improving the yield of solid-phase silicon carbide according to claim 1, characterized in that, The graphite crucible is provided with a fluorinated graphite liner, and the thickness of the fluorinated graphite liner is 3-8 mm.

4. The synthesis method for improving the yield of solid-phase silicon carbide according to claim 1, characterized in that, The process of uniformly spreading the mixed raw materials in a graphite crucible with a fluorinated graphite liner and placing the graphite crucible into a silicon carbide synthesis furnace includes the following steps: S311. A fluorinated graphite liner is installed in the graphite crucible, and the weight and thickness of the mixed raw materials are calculated in advance according to the size and shape of the graphite crucible. S312. The mixed raw materials are evenly spread in the graphite crucible using a layered spreading method, and the uniformity of the mixed raw materials is improved by tapping after each layer is laid. S313. Place the graphite crucible containing the mixed raw materials into the silicon carbide synthesis furnace.

5. The synthesis method for improving the yield of solid-phase silicon carbide according to claim 1, characterized in that, The method of using parameter optimization algorithms to predict the corresponding optimal synthesis parameters based on the input parameters of the mixed raw materials includes the following steps: S321. Obtain historical data on solid-phase synthesis of silicon carbide from the database, and construct and train a performance index evaluation model based on the historical data on solid-phase synthesis of silicon carbide. S322. Use parameter optimization algorithms combined with performance index evaluation models to find the optimal synthetic parameters corresponding to the input parameters in the parameter space.

6. The synthesis method for improving the yield of solid-phase silicon carbide according to claim 5, characterized in that, The process of obtaining historical data on solid-phase silicon carbide synthesis from the database and constructing and training a performance evaluation model based on this data includes the following steps: S3211. Obtain historical data on solid-phase synthesis of silicon carbide from the database and perform preprocessing. The historical data includes particle size and weight data of silicon carbide powder, carbon powder, silicon powder, and polytetrafluoroethylene powder, as well as reaction temperature, heating rate, reaction pressure, and holding time data during synthesis, and the yield and quality of silicon carbide products. S3212. Take 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 during synthesis, as input parameters, and take the yield and mass of silicon carbide product as output parameters. S3213. Construct training and testing sets based on input and output parameters, and use the training and testing sets to train and test the performance evaluation model to obtain a trained performance evaluation model.

7. The synthesis method for improving the yield of solid-phase silicon carbide according to claim 6, characterized in that, The process of finding the optimal synthesized parameters corresponding to the input parameters in the parameter space using a parameter optimization algorithm combined with a performance index evaluation model includes the following steps: S3221. Define the optimization objective and construct an objective function to quantify the optimization objective, wherein the optimization objective is to maximize the yield while meeting product quality and preset cost. S3222. Define the range of values ​​for the synthesis parameters, and randomly generate a set of initial solutions within the range of values ​​for the synthesis parameters. Use the performance index evaluation model to evaluate the performance of the initial solutions. The synthesis parameters include the reaction temperature, heating rate, reaction pressure and holding time data in the solid-state synthesis of silicon carbide. S3223. Generate a new solution set based on selection, crossover and mutation operations of genetic algorithm, evaluate the performance of the newly generated solution using performance index evaluation model, and update the new solution set according to the evaluation results; S3224. Repeat S3223 until the preset number of iterations or the preset performance standard is reached, and select the optimal solution from the current solution set to obtain the best synthesis parameters corresponding to the input parameters.

8. The synthesis method for improving the yield of solid-phase silicon carbide according to claim 7, characterized in that, The process of evaluating the performance of newly generated solutions using a performance index evaluation model and updating the new solution set based on the evaluation results includes the following steps: decoding the newly generated solutions to obtain new synthesis parameters; using the trained performance index evaluation model in conjunction 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, thereby obtaining the performance evaluation results. The fitness value of each solution is calculated based on the performance evaluation results, and the new solution set is updated according to the fitness value calculation results.

9. A silicon carbide synthesis furnace, used to synthesize silicon carbide in the synthesis method according to any one of claims 1-8 that can improve the yield of solid-phase silicon carbide synthesis, characterized in that, The silicon carbide synthesis furnace includes a synthesis furnace (1), the inner sidewall of which is provided with several sets of heating components (2), and each set of heating components (2) is composed of several heating coils. Each set of heating components (2) is connected to an induction power supply (3) through a wire, and the induction power supply (3) is electrically connected to a control cabinet (4). The inside of the synthesis furnace (1) is provided with a graphite crucible (5), and the inner wall of the graphite crucible (5) is provided with a fluorinated graphite lining layer (6).

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