A method and system for expanding the diameter of a silicon carbide crystal based on laser-assisted heating

Abstract

The present application relates to the technical field of laser diameter expansion system regulation, a silicon carbide crystal diameter expansion method and system based on laser auxiliary heating, comprising: based on the target blowing angle in the main jet nozzle and gas auxiliary parameters, nozzle angle regulation operation is carried out to obtain the adjusted main jet nozzle, gas flow field test regulation is carried out on the fixed silicon carbide crystal to obtain the optimal nozzle angle, nozzle angle correction operation is carried out on the adjusted main jet nozzle to obtain the optimal angle main jet nozzle, offset distance regulation is carried out on the optimal angle main jet nozzle to obtain the calibrated main jet nozzle, crystal diameter expansion regulation operation is carried out on the fixed silicon carbide crystal to obtain the expanded silicon carbide crystal, and the diameter expansion of the silicon carbide crystal based on laser auxiliary heating is completed based on the expanded silicon carbide crystal. The present application can realize dynamic and accurate regulation of the thermal field in the diameter expansion process, real-time adaptive adjustment of gas phase transport and composition.

Description

Technical Field

[0001] This invention relates to the field of laser diameter expansion system control technology, and in particular to a method and system for expanding the diameter of silicon carbide crystals based on laser-assisted heating. Background Technology

[0002] Laser-assisted heating is a technology that uses laser light as a heat source to heat a target object. Silicon carbide crystal diameter expansion refers to increasing the diameter of a silicon carbide crystal through specific techniques to meet particular application requirements.

[0003] In current mainstream growth technologies, traditional heating methods struggle to achieve precise control of the thermal field during diameter expansion, easily leading to unreasonable temperature gradients and problems such as thermal stress accumulation and crystal cracking. Simultaneously, lag in gas-phase transport and composition control results in prominent phenomena such as edge polycrystalline nucleation and defect aggregation, severely impacting diameter expansion yield and crystal quality. Laser heating offers advantages such as precision, speed, and concentrated energy, allowing for targeted optimization of temperature distribution in the diameter expansion region, adjustment of gas-phase transport efficiency, and suppression of edge defects and stress accumulation. Therefore, achieving dynamic and precise control of the thermal field and real-time adaptive adjustment of gas-phase transport and composition during diameter expansion is a pressing technical challenge. Summary of the Invention

[0004] This invention provides a method for expanding the diameter of silicon carbide crystals based on laser-assisted heating and a computer-readable storage medium. Its main purpose is to achieve dynamic and precise control of the thermal field and real-time adaptation and adjustment of gas phase transport and composition during the diameter expansion process.

[0005] To achieve the above objectives, the present invention provides a method for expanding the diameter of silicon carbide crystals based on laser-assisted heating, comprising: The silicon carbide crystal, laser, main nozzle and auxiliary nozzle were identified, and the silicon carbide crystal was fixed to obtain a fixed silicon carbide crystal. Set the gas-assisted parameters, which include: target blowing angle, negative offset distance, and argon flow rate; The processing start point position is determined based on the fixed silicon carbide crystal, and a three-dimensional rectangular crystal coordinate system is constructed based on the processing start point position; Based on the target blowing angle in the main jet nozzle and gas auxiliary parameters, the nozzle angle is adjusted to obtain the adjusted main jet nozzle; Based on the adjusted main jet nozzle, the gas flow field of the fixed silicon carbide crystal was tested and controlled to obtain the optimal nozzle angle; The nozzle angle of the adjusted main jet nozzle is corrected using the optimal nozzle angle to obtain the optimal main jet nozzle angle. The offset distance of the optimal angle main jet nozzle is adjusted based on a three-dimensional rectangular crystal coordinate system to obtain a calibrated main jet nozzle. Based on the calibration of the main jet nozzle, laser and auxiliary jet nozzle, crystal diameter expansion control operation is performed on the fixed silicon carbide crystal to obtain the expanded silicon carbide crystal; Laser-assisted heating was used to expand the diameter of silicon carbide crystals based on the expanded diameter silicon carbide crystals.

[0006] Optionally, the nozzle angle adjustment operation based on the target blowing angle in the main jet nozzle and gas auxiliary parameters to obtain the adjusted main jet nozzle includes: The initial angle of the main jet nozzle is measured to obtain the initial measurement angle. The angle adjustment amount is calculated based on the target blowing angle in the gas auxiliary parameters and the initial measurement angle. If the angle adjustment amount is greater than the preset zero value, the angle of the main jet nozzle is increased according to the preset coarse adjustment step size to obtain the coarse adjustment main jet nozzle; If the angle adjustment amount is less than zero, the main jet nozzle is adjusted by reducing the angle according to the coarse adjustment step size to obtain the coarse adjustment main jet nozzle; The coarse-adjusted main jet nozzle is precisely adjusted until the angle adjustment is equal to zero, thus obtaining the adjusted main jet nozzle.

[0007] Optionally, the step of adjusting the offset distance of the optimal angle main jet nozzle based on a three-dimensional rectangular crystal coordinate system to obtain a calibrated main jet nozzle includes: The theoretical intersection coordinates are calculated based on the negative offset distance and the three-dimensional rectangular crystal coordinate system. The nozzle axis direction vector is determined based on the optimal nozzle angle corresponding to the optimal angle main jet nozzle. The optimal angle main jet nozzle is height-adjusted based on the nozzle axis direction vector to obtain the standard height main jet nozzle. The standard height main jet nozzle is then moved laterally based on the negative offset distance in the theoretical intersection coordinates to obtain the coarse positioning main jet nozzle. The actual measured value is calculated based on the coarse positioning main jet nozzle, and the deviation is calculated based on the actual measured value and the negative offset distance to obtain the offset difference value; If the offset difference is not within the preset deviation range, the coarse positioning main jet nozzle is laterally adjusted to obtain an adjusted main jet nozzle. The adjusted main jet nozzle is then used as the coarse positioning main jet nozzle. The process is repeated until the offset difference is within the deviation range. If the bias difference is within the deviation range, the adjusted main jet nozzle is used as the calibrated main jet nozzle.

[0008] Optionally, the calculation of actual measured values ​​based on the coarse positioning main jet nozzle includes: The laser sensor readings are obtained based on the coarse positioning main jet nozzle, and the vertical distance is calculated based on the laser sensor readings and the preset installation offset value. The actual measured value is calculated based on the vertical distance, optimal nozzle angle, and installation offset. The formula for calculating the actual measured value is as follows: , in, This represents the actual measured value. Indicates vertical distance. Indicates the optimal nozzle angle. Represents the tangent function. This indicates the installation offset value.

[0009] Optionally, the step of performing crystal diameter expansion control operation on the fixed silicon carbide crystal based on calibrating the main jet nozzle, laser, and auxiliary jet nozzle to obtain the expanded silicon carbide crystal includes: The surface feature points of the silicon carbide crystal are identified to obtain the starting position of the diameter expansion center. Based on the starting position of the diameter expansion center, the laser is positioned and controlled to obtain the positioned laser. A power gradient set is set up, and based on the positioned laser, the calibrated main nozzle, the auxiliary nozzle, and the power gradient set, a crystal diameter expansion control operation is performed on the fixed silicon carbide crystal to obtain a silicon carbide crystal with expanded diameter.

[0010] Optionally, the step of performing crystal diameter expansion control operation on the fixed silicon carbide crystal based on the positioned laser, calibrated main nozzle, secondary nozzle, and power gradient set to obtain the expanded silicon carbide crystal includes: The first power gradient is extracted from the power gradient set, and the target number of revolutions parameters are determined based on the first power gradient. The target number of revolutions parameters include: scanning speed and helix spacing. The power of the located laser is set based on the first power gradient and the target number of cycles to obtain the first laser. The fixed silicon carbide crystal was simultaneously scanned using the first laser, the secondary jet nozzle, and the calibration main jet nozzle to obtain the preliminary diameter-expanded crystal, the crystal center point temperature, the scanning front temperature, and the temperature of the processed area. The average temperature of the crystal is obtained by weighted summing of the temperature at the crystal center point, the temperature at the scanning front edge, and the temperature of the processed area. The updated power gradient is obtained by performing power regulation operation based on the average temperature of the crystal. The updated power gradient is used as the first power gradient, and the initially expanded crystal is used as the fixed silicon carbide crystal. The process is repeated until the updated power gradient equals the preset end power gradient. The updated power gradients are summarized to obtain the updated power gradient set, and the expanded silicon carbide crystal is identified based on the updated power gradient set.

[0011] Optionally, the simultaneous scanning operation of the fixed silicon carbide crystal using a first laser, a secondary jet nozzle, and a calibration main jet nozzle to obtain the preliminary diameter-expanded crystal, the crystal center point temperature, the scanning front temperature, and the processed area temperature includes: The flow rate of the argon gas is controlled by the pre-constructed flow control system to obtain the main nozzle of the gas to be sprayed. The gas flow rate of the main nozzle of the gas to be sprayed is controlled to obtain the gas flow field environment. Based on the gas flow field environment, the first laser and the secondary jet nozzle are used to perform synchronous processing operations on the fixed silicon carbide crystal to obtain the initial diameter-expanded crystal. Temperature data was collected from the initial expanded crystal to obtain the temperature at the crystal center point, the scanning front temperature, and the temperature of the processed area.

[0012] Optionally, the power modulation operation based on the crystal average temperature to obtain the updated power gradient includes: Adjacent power gradients are identified from the power gradient set based on the first-order power gradient. If the average temperature of the crystal is greater than the preset end temperature limit, then the power reduction operation is performed on the adjacent power gradient to obtain the first controlled power gradient. If the average temperature of the crystal is less than the preset lower limit of the end temperature, then the power gradient of the adjacent power gradient is increased to obtain the second controlled power gradient. If the average crystal temperature is not greater than the upper limit of the termination temperature and not less than the lower limit of the termination temperature, then the adjacent power gradients are taken as the optimal power gradients. The updated power gradient is determined based on the first controlled power gradient, the second controlled power gradient, or the optimal power gradient.

[0013] Optionally, the formula for calculating the first controlled power gradient is as follows: , in, This represents the first control power gradient. Indicates the adjacent power gradient, This represents the natural exponential function. Indicates the average temperature of the crystal. Indicates the upper limit of the end temperature. This indicates the preset thermal inertia compensation temperature.

[0014] To achieve the above objectives, the present invention also provides a silicon carbide crystal diameter expansion system based on laser-assisted heating, comprising: The control parameter setting module is used to identify the silicon carbide crystal, laser, main nozzle and auxiliary nozzle, fix the silicon carbide crystal to obtain a fixed silicon carbide crystal, and set the gas auxiliary parameters, including: target blowing angle, negative bias distance and argon flow rate. The nozzle angle control module is used to determine the processing start position based on the fixed silicon carbide crystal, construct a three-dimensional rectangular crystal coordinate system based on the processing start position, perform nozzle angle control operation based on the target blowing angle in the main jet nozzle and gas auxiliary parameters to obtain the adjusted main jet nozzle, perform gas flow field test and control on the fixed silicon carbide crystal based on the adjusted main jet nozzle to obtain the optimal nozzle angle, perform nozzle angle correction operation on the adjusted main jet nozzle using the optimal nozzle angle to obtain the optimal angle main jet nozzle, and adjust the offset distance of the optimal angle main jet nozzle based on the three-dimensional rectangular crystal coordinate system to obtain the calibrated main jet nozzle; The crystal diameter expansion control module is used to perform crystal diameter expansion control operations on a fixed silicon carbide crystal based on the calibration of the main jet nozzle, laser and auxiliary jet nozzle, to obtain a silicon carbide crystal with expanded diameter; The crystal diameter expansion control module is used to complete the diameter expansion of a silicon carbide crystal based on laser-assisted heating, using an already expanded silicon carbide crystal.

[0015] To address the above problems, the present invention also provides an electronic device, the electronic device comprising: Memory, storing at least one instruction; The processor executes the instructions stored in the memory to implement the laser-assisted heating-based silicon carbide crystal diameter expansion method described above.

[0016] To address the aforementioned problems, the present invention also provides a computer-readable storage medium storing at least one instruction, which is executed by a processor in an electronic device to implement the aforementioned method for expanding the diameter of silicon carbide crystals based on laser-assisted heating.

[0017] To address the problems described in the background art, this invention identifies the silicon carbide crystal, laser, main nozzle, and auxiliary nozzle, fixes the silicon carbide crystal to obtain a fixed silicon carbide crystal, and sets gas-assisted parameters, including the target blowing angle, negative offset distance, and argon flow rate. This invention ensures the stability of the crystal's spatial position during all subsequent processing and control operations by fixing it, avoiding processing deviations and inaccurate positioning caused by crystal displacement. Based on the fixed silicon carbide crystal, the processing starting point position is determined, and a three-dimensional Cartesian crystal coordinate system is constructed based on this starting point position. This three-dimensional Cartesian crystal coordinate system is used for subsequent laser positioning, nozzle angle adjustment, and offset distance adjustment. This invention provides a unified spatial reference for all spatial location-related operations, enabling precise spatial positioning throughout the entire processing flow and eliminating control deviations caused by inconsistent spatial references. Based on the target blowing angle in the main jet nozzle and gas auxiliary parameters, the nozzle angle is adjusted to obtain an adjusted main jet nozzle. This invention adjusts the blowing angle of the main jet nozzle to the target value preset by the process, allowing the argon gas injection direction of the main jet nozzle to initially adapt to the gas requirements of the crystal diameter expansion processing area. Based on the adjusted main jet nozzle, gas flow field testing and control are performed on the fixed silicon carbide crystal to obtain the optimal nozzle angle. This invention verifies and optimizes the blowing angle of the main jet nozzle through actual flow field testing, confirming that it can form a stable and adaptable flow field in the crystal processing area for diameter expansion. This invention optimizes the nozzle angle for the gas flow field, avoiding problems such as flow field disturbance and poor argon protection caused by unreasonable angles. It corrects the nozzle angle of the pre-adjusted main jet nozzle using the optimal nozzle angle, resulting in an optimal main jet nozzle. This precise correction of the main jet nozzle angle to its optimal value enables it to stably output the optimal gas flow field, providing a precisely angled nozzle for subsequent offset distance control. The offset distance of the optimal main jet nozzle is then controlled based on a three-dimensional Cartesian crystal coordinate system, resulting in a calibrated main jet nozzle. This invention achieves precise control of the main jet nozzle offset distance using a unified spatial reference, ensuring that the spatial relative position of the main jet nozzle and the crystal processing area matches the process requirements. By optimizing the nozzle angle, the calibrated jet nozzle can create an argon gas environment with optimal position, angle, and flow field in the crystal processing area. Based on the calibrated main jet nozzle, laser, and auxiliary jet nozzle, crystal diameter expansion control is performed on the fixed silicon carbide crystal to obtain an expanded silicon carbide crystal. This invention relies on the optimal gas flow field support of the calibrated jet nozzle, combined with the laser to complete the entire process control of crystal diameter expansion, achieving precise synergy between laser heating and argon assistance. This ensures the dimensional accuracy and forming quality of the crystal diameter expansion, avoiding problems such as crystal oxidation, thermal cracking, and irregular forming caused by insufficient gas assistance, resulting in an expanded crystal that meets the process requirements. Based on the expanded silicon carbide crystal, laser-assisted heating is used to complete the diameter expansion of silicon carbide crystals. Therefore, this invention can achieve dynamic and precise control of the thermal field and real-time adaptation and adjustment of gas phase transport and composition during the diameter expansion process. Attached Figure Description

[0018] Figure 1 This is a schematic flowchart of a method for expanding the diameter of silicon carbide crystals based on laser-assisted heating, provided in an embodiment of the present invention. Figure 2 This is a functional block diagram of a silicon carbide crystal diameter expansion system based on laser-assisted heating, provided in an embodiment of the present invention. Figure 3 A schematic diagram of the structure of an electronic device for implementing the laser-assisted heating-based silicon carbide crystal diameter expansion method according to an embodiment of the present invention; Figure 4 A schematic diagram of a three-dimensional rectangular crystal coordinate system for implementing the laser-assisted heating-based silicon carbide crystal diameter expansion method according to an embodiment of the present invention; Figure 5 This is a schematic diagram of laser diameter expansion processing for implementing the laser-assisted heating method for expanding the diameter of silicon carbide crystals, as provided in an embodiment of the present invention.

[0019] Explanation of reference numerals in the attached figures: 1. Electronic equipment; 10. Processor; 11. Memory; 12. Bus; 200. Fixed silicon carbide crystal; 201. Machining start position; 400. Machining table; 301. Laser; 302. Laser center axis; 501. Main nozzle; 502. Main nozzle center axis; 600. Secondary nozzle.

[0020] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0021] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0022] This application provides a method for expanding the diameter of silicon carbide crystals based on laser-assisted heating. The executing entity of this method includes, but is not limited to, at least one of the following electronic devices that can be configured to execute the method provided in this application: a server, a terminal, etc. In other words, the method for expanding the diameter of silicon carbide crystals based on laser-assisted heating can be executed by software or hardware installed on a terminal device or a server device, and the software can be a blockchain platform. The server includes, but is not limited to, a single server, a server cluster, a cloud server, or a cloud server cluster.

[0023] Reference Figure 1 The diagram shown is a schematic flowchart of a silicon carbide crystal diameter expansion method based on laser-assisted heating according to an embodiment of the present invention. In this embodiment, the silicon carbide crystal diameter expansion method based on laser-assisted heating includes: S1. Identify the silicon carbide crystal, laser, main nozzle, and auxiliary nozzle, and fix the silicon carbide crystal to obtain a fixed silicon carbide crystal.

[0024] It should be explained that silicon carbide crystal is a silicon carbide material blank with a specific crystal structure. The laser is a device that enables laser-assisted heating, used to output a laser beam of specific power and wavelength to the area of ​​the silicon carbide crystal to be expanded, providing the heating energy required for crystal expansion and creating the necessary temperature conditions for the crystal expansion process. The main nozzle is a nozzle that injects argon gas into the area of ​​the silicon carbide crystal to be expanded according to gas assistance parameters. The main nozzle achieves precise control of the gas flow field in the processing area through angle adjustment and offset distance adjustment, cooperating with laser heating to complete crystal expansion. The auxiliary nozzle is another nozzle in the gas assistance system of this invention, working in conjunction with the main nozzle to form a complete gas injection system. The auxiliary nozzle is used to cooperate with the main nozzle to deliver argon gas to the silicon carbide crystal processing area, jointly optimizing the gas flow field environment in the processing area and ensuring the uniformity and stability of the argon-assisted effect. Fixing the silicon carbide crystal involves using a special tooling fixture adapted to the shape of the silicon carbide crystal, combined with mechanical positioning or precision adsorption positioning, to fix the silicon carbide crystal on the processing station. Fixed silicon carbide crystals are silicon carbide crystals that have already been fixed.

[0025] S2. Set the gas auxiliary parameters, which include: target blowing angle, negative offset distance and argon flow rate.

[0026] It should be explained that the target blowing angle is the blowing angle at which the main nozzle injects argon gas into the region of the silicon carbide crystal to be expanded, and is an auxiliary... Figure 5 The theoretical angle between the central axis of the main jet nozzle and the surface of the silicon carbide crystal. The negative offset distance is the offset distance of the main jet nozzle relative to the fixed region of the silicon carbide crystal to be expanded and the subsequently constructed three-dimensional rectangular crystal coordinate system. The argon flow rate is the flow rate per unit time of argon gas injected into the region of the silicon carbide crystal to be expanded by the main and auxiliary jet nozzles. The negative offset distance corresponds to... Figure 5 The position of point M in the diagram, that is, the coordinate value of the intersection of the central axis of the main nozzle (i.e., the central axis 502 of the main nozzle) and the surface of the silicon carbide crystal in the x-axis.

[0027] S3. Based on the fixed silicon carbide crystal, the processing start point position is determined, and a three-dimensional rectangular crystal coordinate system is constructed based on the processing start point position.

[0028] It should be explained that the processing starting point is the fixed geometric center position within the silicon carbide crystal. The silicon carbide crystal diameter expansion process requires determining a unique processing starting point to provide a unified starting reference for all subsequent processing operations (i.e., the attached...). Figure 5Point O in the diagram. Since the geometric center is the symmetrical core of the crystal's diameter-expanding region, using it as the starting point allows subsequent laser scanning and gas jet diameter-expanding operations to proceed evenly outwards from the center, avoiding problems such as diameter-expanding misalignment and irregular forming caused by starting point offset. Simultaneously, the geometric center serves as the inherent geometric reference for the crystal's diameter-expanding region, ensuring precise positioning and strong stability. The steps for constructing a three-dimensional rectangular crystal coordinate system based on the processing starting point are as follows: Establish a right-handed rectangular coordinate system with the processing starting point as the origin; this is the three-dimensional rectangular crystal coordinate system. An example diagram of the three-dimensional rectangular crystal coordinate system is shown below. Figure 4 As shown, in this invention, the silicon carbide crystal is a cuboid, wherein the three-dimensional rectangular crystal coordinate system includes: the horizontal axis is parallel to the long side of the fixed silicon carbide crystal, and the direction extending along the long side is the positive direction; the vertical axis is perpendicular to the horizontal plane formed by the horizontal axis and the vertical axis, and the direction of the normal of the upper surface of the horizontal plane outward (that is, the direction of the silicon carbide crystal being placed horizontally in the processing position, away from the ground) is the positive direction.

[0029] S4. Based on the target blowing angle in the main jet nozzle and gas auxiliary parameters, perform nozzle angle adjustment operation to obtain the adjusted main jet nozzle.

[0030] In detail, the nozzle angle adjustment operation based on the target blowing angle in the main jet nozzle and gas auxiliary parameters to obtain the adjusted main jet nozzle includes: The initial angle of the main jet nozzle is measured to obtain the initial measurement angle. The angle adjustment amount is calculated based on the target blowing angle in the gas auxiliary parameters and the initial measurement angle. If the angle adjustment amount is greater than the preset zero value, the angle of the main jet nozzle is increased according to the preset coarse adjustment step size to obtain the coarse adjustment main jet nozzle; If the angle adjustment amount is less than zero, the main jet nozzle is adjusted by reducing the angle according to the coarse adjustment step size to obtain the coarse adjustment main jet nozzle; The coarse-adjusted main jet nozzle is precisely adjusted until the angle adjustment is equal to zero, thus obtaining the adjusted main jet nozzle.

[0031] It should be explained that the initial angle measurement of the main jet nozzle is an operation performed before the main jet nozzle angle adjustment operation. Using a constructed three-dimensional rectangular crystal coordinate system as a spatial reference, high-precision angle measuring equipment such as angle sensors and laser goniometers are employed to accurately detect and collect data on the current actual jet angle of the main jet nozzle. The initial measurement angle refers to the current actual jet angle of the main jet nozzle obtained after the initial angle measurement is completed. The current actual jet angle of the main jet nozzle corresponds to... Figure 5 Angle B is the included angle in the ZOX plane, and angle B lies within the ZOX plane.

[0032] It should also be explained that the angle adjustment amount is the difference between the target blowing angle and the initial measured angle. The zero value in this invention is 0. If the angle adjustment amount is greater than the preset zero value, it indicates that the current actual blowing angle of the main nozzle is less than the target blowing angle. Rotation adjustment is needed to increase the blowing angle of the main nozzle. The increased angle is the angle between the central axis of the main nozzle and the silicon carbide crystal surface. The increased angle adjustment amount ensures that the blowing angle of the main nozzle is the target blowing angle. Both the angle increase and decrease adjustments can be performed using a high-precision electric rotary table. This adjustment operation is existing technology and will not be described in detail here. The coarse adjustment step size is a preset fixed angle value for each rotation adjustment of the main nozzle during the coarse adjustment stage, used to quickly reduce the difference between the actual angle of the main nozzle and the target blowing angle. The coarse adjustment step size setting method is as follows: based on the process efficiency and mechanical rotation adaptability of the main jet nozzle angle control, a fixed angle value for each rotation adjustment of the main jet nozzle in the coarse adjustment stage is set in advance through process simulation or engineering test. The setting of this angle value must match the performance of the mechanical rotation mechanism of the main jet nozzle, while taking into account the process goal of rapidly reducing the angle difference in the coarse adjustment stage. This ensures that the set coarse adjustment step size allows the main jet nozzle to quickly approach the corresponding target blowing angle with the fewest number of rotation adjustments, while preventing the remaining angle difference after coarse adjustment from exceeding the reasonable range of precision control due to an excessively large step size.

[0033] Importantly, the coarse-adjusted main jet nozzle is the main jet nozzle after coarse adjustment step size. If the angle adjustment amount is less than zero, it means that the current actual jet angle of the main jet nozzle is greater than the target blowing angle. Rotation adjustment is needed to reduce the jet angle of the main jet nozzle to bring it closer to the target blowing angle. The coarse-adjusted main jet nozzle is the main jet nozzle obtained after increasing or decreasing the angle adjustment. The precision control operation of the coarse-adjusted main jet nozzle is based on a three-dimensional rectangular crystal coordinate system, using a high-precision angle control device (such as a piezoelectric ceramic driven precision angle adjustment stage or a manual precision micrometer head rotary adjustment stage). The coarse adjustment step size is switched to a fine adjustment step size much smaller than its value. The coarse-adjusted main jet nozzle is rotated and adjusted in small increments. After each adjustment, the actual angle of the main jet nozzle is detected in real time, and the remaining difference between the current angle and the target blowing angle is calculated. This operation is repeated until the remaining difference is zero, i.e., the angle adjustment amount equals zero. The adjusted main jet nozzle is the main jet nozzle whose actual jet angle is perfectly matched to the target blowing angle after the coarse-adjusted main jet nozzle has undergone precision control operation. For example, the coarse adjustment step size is 2°, and the fine adjustment step size is 0.1°.

[0034] It should be noted that in the above steps of this invention, in order to clarify the deviation value and specific adjustment direction between the actual blowing angle of the main jet nozzle and the target blowing angle, and to provide a precise and quantifiable basis for subsequent rotation adjustment operations, and to avoid blind adjustment without data support, this invention performs difference calculation between the target blowing angle and the initial measured angle of the main jet nozzle, so as to accurately obtain the angle adjustment amount between the two. Since it is necessary to efficiently reduce the difference between the actual angle of the main jet nozzle and the target blowing angle, so that the blowing angle of the main jet nozzle quickly approaches the target blowing angle, while shortening the overall angle control time and improving the efficiency of process operation, this invention determines the rotation adjustment direction of the main jet nozzle based on the positive or negative result of the angle adjustment amount, and performs rotation adjustment of the main jet nozzle in the corresponding direction according to a fixed coarse adjustment step size, so as to achieve rapid reduction of angle deviation. Meanwhile, since it is necessary to accurately match the actual blowing angle of the main jet nozzle to the target blowing angle, and to ensure that the blowing angle of the main jet nozzle strictly meets the accuracy requirements of the silicon carbide crystal diameter expansion process, after the coarse adjustment operation is completed, the present invention performs a precision adjustment operation on the coarse adjustment main jet nozzle. Based on the coarse adjustment, a small-amplitude precision angle calibration is performed to eliminate the remaining small deviation between the main jet nozzle and the target blowing angle.

[0035] S5. Based on the adjusted main jet nozzle, the gas flow field of the fixed silicon carbide crystal is tested and controlled to obtain the optimal nozzle angle.

[0036] Understandably, the steps for testing and controlling the gas flow field of a fixed silicon carbide crystal based on the adjusted main nozzle are as follows: Using the adjusted main nozzle as a base, aim the nozzle at the area to be expanded on the fixed silicon carbide crystal according to the currently matched target blowing angle, and inject argon gas into the area. Simultaneously, use flow field detection equipment to perform real-time detection and data acquisition of key flow field indicators such as argon flow field distribution, flow field intensity, and flow stability in the silicon carbide crystal processing area. By fine-tuning the blowing angle of the adjusted main nozzle and simultaneously recording the flow field detection data at different angles, compare whether the flow field indicators corresponding to each angle are suitable for the process requirements of laser-assisted heating expansion of the silicon carbide crystal, and select the nozzle angle that can form a uniform, stable argon flow field in the processing area that meets the process parameter requirements. The step of using flow field detection equipment to perform real-time detection and data acquisition of key flow field indicators such as argon flow field distribution, flow field intensity, and flow stability in the silicon carbide crystal processing area can be achieved using existing technology and will not be elaborated here. The optimal nozzle angle is selected from the flow field detection data corresponding to different nozzle angles during the gas flow field testing and control of silicon carbide crystals. It is the nozzle angle that can make the diameter expansion processing area of ​​the fixed silicon carbide crystal form a nozzle angle that is fully adapted to the requirements of the laser-assisted heating diameter expansion process.

[0037] S6. Use the optimal nozzle angle to perform nozzle angle correction operation on the adjusted main jet nozzle to obtain the optimal angle main jet nozzle.

[0038] Understandably, the steps for correcting the nozzle angle of the adjusted main jet nozzle using the optimal nozzle angle are as follows: Using the optimal nozzle angle as the new angle reference, the difference between the optimal nozzle angle and the current actual blowing angle of the adjusted main jet nozzle is calculated to obtain the angle correction amount. Based on this angle correction amount, a high-precision angle control device is used to perform targeted rotational adjustment of the adjusted main jet nozzle. During the adjustment process, the actual angle of the main jet nozzle is monitored in real time until the actual blowing angle of the main jet nozzle precisely matches the optimal nozzle angle, thus completing the nozzle angle correction operation for the adjusted main jet nozzle. The optimal angle main jet nozzle is the adjusted main jet nozzle after the correction operation corresponding to the optimal nozzle angle.

[0039] S7. Based on the three-dimensional rectangular crystal coordinate system, the offset distance of the main jet nozzle at the optimal angle is adjusted to obtain the calibrated main jet nozzle.

[0040] In detail, the process of adjusting the offset distance of the optimal angle main jet nozzle based on a three-dimensional rectangular crystal coordinate system to obtain a calibrated main jet nozzle includes: The theoretical intersection coordinates are calculated based on the negative offset distance and the three-dimensional rectangular crystal coordinate system. The nozzle axis direction vector is determined based on the optimal nozzle angle corresponding to the optimal angle main jet nozzle. The optimal angle main jet nozzle is height-adjusted based on the nozzle axis direction vector to obtain the standard height main jet nozzle. The standard height main jet nozzle is then moved laterally based on the negative offset distance in the theoretical intersection coordinates to obtain the coarse positioning main jet nozzle. The actual measured value is calculated based on the coarse positioning main jet nozzle, and the deviation is calculated based on the actual measured value and the negative offset distance to obtain the offset difference value; If the offset difference is not within the preset deviation range, the coarse positioning main jet nozzle is laterally adjusted to obtain an adjusted main jet nozzle. The adjusted main jet nozzle is then used as the coarse positioning main jet nozzle. The process is repeated until the offset difference is within the deviation range. If the bias difference is within the deviation range, the adjusted main jet nozzle is used as the calibrated main jet nozzle.

[0041] It should be explained that the step of calculating the theoretical intersection coordinates based on the negative offset distance and the three-dimensional rectangular crystal coordinate system is as follows: taking the processing starting point as the origin and the fixed silicon carbide crystal surface as the Z=0 plane, the distance (absolute value of the negative offset distance) is measured along the negative X-axis (because the negative offset distance is negative) to obtain the coordinates of the theoretical intersection point. The nozzle axis direction vector is the vector that characterizes the spatial extension direction of the argon jet axis of the main jet nozzle, which is the optimal nozzle angle corresponding to the optimal angle main jet nozzle, determined in the three-dimensional rectangular crystal coordinate system. The height adjustment of the optimal angle main jet nozzle based on the nozzle axis direction vector is carried out under the nozzle axis direction vector, with the vertical axis of the three-dimensional rectangular crystal coordinate system as the height adjustment reference. According to the pre-set main jet nozzle height process requirements of the silicon carbide crystal diameter expansion process, a high-precision displacement control device is used to adjust the optimal angle main jet nozzle along the vertical axis until the actual height of the main jet nozzle is equal to the pre-set process height. The standard height main jet nozzle is the optimal angle main jet nozzle after height adjustment. The lateral movement is a directional translation operation performed along the lateral direction (horizontal axis) of the three-dimensional rectangular crystal coordinate system, using the horizontal axis as the lateral adjustment reference. This is done according to the lateral offset corresponding to the negative offset distance in the theoretical intersection coordinates. The coarse positioning main jet nozzle is the standard height main jet nozzle after this lateral movement. Detailed steps for calculating the actual measurement value based on the coarse positioning main jet nozzle will be given later. The offset difference is the difference obtained by subtracting the negative offset distance from the actual measurement value. It should be noted that the offset difference can be positive, negative, or zero, and the sign of the difference directly corresponds to the horizontal axis direction: positive values ​​correspond to the positive direction of the horizontal axis, negative values ​​correspond to the negative direction, and zero indicates that the actual offset position coincides with the theoretical position, with no directional attribute. If the actual offset position of the coarse positioning main jet nozzle is in the positive direction of the horizontal axis, the direction of the offset difference is in the positive direction of the horizontal axis; if the actual offset position of the coarse positioning main jet nozzle is in the negative direction of the horizontal axis, the direction of the offset difference is in the negative direction of the horizontal axis.

[0042] Understandably, the deviation range is a pre-defined, reasonable fluctuation range for the offset difference, set by the process. The deviation range is determined by: based on the accuracy requirements of the main nozzle offset distance in the silicon carbide crystal expansion process, combined with the spatial positioning accuracy of the three-dimensional rectangular crystal coordinate system, the actual control accuracy of the main nozzle displacement control device, and the tolerance of the argon gas flow field to small deviations in the offset distance, pre-determining the upper and lower limits of the allowable offset difference through process simulation and actual debugging tests. These upper and lower limits define the reasonable fluctuation range of the offset difference. If the offset difference is not within the pre-defined deviation range, it indicates that the deviation between the actual offset distance and the negative offset distance of the coarse-positioned main nozzle exceeds the deviation range, and its current lateral spatial position does not meet the accuracy requirements of the silicon carbide crystal expansion process for the main nozzle offset distance, requiring further lateral adjustment. The lateral adjustment operation for the coarse positioning main nozzle uses the horizontal axis of the three-dimensional rectangular crystal coordinate system as the lateral adjustment reference. Based on the value and direction of the offset difference, a high-precision displacement control device is used to adjust the coarse positioning main nozzle by lateral translation. The adjusted main nozzle is the main nozzle obtained after the lateral adjustment operation of the coarse positioning main nozzle. If the offset difference is within the deviation range, it indicates that the deviation between the actual offset distance and the negative offset distance of the coarse positioning main nozzle is within the reasonable fluctuation range allowed by the process, and its current spatial position fully meets the accuracy requirements of the main nozzle offset distance for the silicon carbide crystal diameter expansion process, requiring no further lateral adjustment. The calibrated main nozzle is the adjusted main nozzle whose offset difference is within the deviation range.

[0043] It should be noted that the offset distance of the main jet nozzle directly determines the spatial relative position between the main jet nozzle and the area of ​​the silicon carbide crystal to be expanded. This spatial relative position directly affects the flow field distribution, intensity, and stability after argon injection. At the same time, spatial positioning deviation of the main jet nozzle can easily cause problems such as flow field disturbance and uneven crystal expansion. In order to ensure that the argon flow field and the laser heating area are accurately matched, guarantee the gas-assisted expansion effect, avoid the process problems caused by the above positioning deviation, and ensure that the spatial position of the main jet nozzle fully meets the process accuracy requirements of silicon carbide crystal expansion, this invention, in the laser-assisted heating expansion process of silicon carbide crystal, adjusts the offset distance of the main jet nozzle at the optimal angle based on the precise positioning and deviation closed-loop calibration of the three-dimensional rectangular crystal coordinate system. Finally, the offset distance is precisely adjusted to a negative offset distance, providing gas-assisted support with precise position and stable flow field for subsequent crystal expansion control operations.

[0044] Importantly, the negative of the negative offset distance corresponds to the negative direction of the horizontal axis in a three-dimensional Cartesian crystal coordinate system. Positioning the main jet nozzle in the positive horizontal axis direction, but with the intersection of its central axis and the horizontal axis falling in the negative direction, serves two purposes: First, it allows the argon gas to be injected at the optimal angle and along a reasonable path to form a protective flow field, fully covering the area of ​​the crystal to be expanded. This effectively isolates the crystal from air to prevent high-temperature oxidation and avoids the airflow directly hitting the laser heating focus, thus preventing disturbances in the thermal field distribution. This solves the problems of thermal field disturbances and flow field blind spots that easily occur with positive offset. Second, it creates a clear spatial partition with equipment such as lasers and auxiliary jet nozzles positioned in the positive vertical axis direction. This layout avoids physical collisions and operational path conflicts during equipment installation and operation, which can lead to various operational obstacles caused by the clustering of multiple devices with positive offset. Using a positive offset distance would not only disrupt the spatial positioning logic of the coordinate system, leading to chaotic flow field control operations, but also cause a series of process problems such as laser thermal field disturbances, crystal processing area oxidation, and equipment interference due to changes in airflow direction and equipment spatial layout, making it impossible to guarantee the accuracy and stability of silicon carbide crystal diameter expansion processing. For these reasons, this invention positions the intersection of the central axis of the main jet nozzle and the horizontal axis in the negative direction of the horizontal axis, i.e., a negative offset distance.

[0045] In detail, the calculation of actual measured values ​​based on the coarse positioning main jet nozzle includes: The laser sensor readings are obtained based on the coarse positioning main jet nozzle, and the vertical distance is calculated based on the laser sensor readings and the preset installation offset value. The actual measured value is calculated based on the vertical distance, optimal nozzle angle, and installation offset. The formula for calculating the actual measured value is as follows: , in, This represents the actual measured value. Indicates vertical distance. Indicates the optimal nozzle angle. Represents the tangent function. This indicates the installation offset value.

[0046] It should be explained that the step of obtaining laser sensor readings based on the coarse positioning main jet nozzle is as follows: The laser sensor is installed at the processing station according to the preset process position, with the detection optical path of the laser sensor aligned with the outlet of the coarse positioning main jet nozzle. The laser sensor is activated to perform non-contact distance detection on the coarse positioning main jet nozzle. The value output by the laser sensor after detection, representing the actual distance between the sensor and the outlet of the coarse positioning main jet nozzle, is directly read; this is the laser sensor reading. The vertical distance is the distance obtained by subtracting the installation offset value from the laser sensor reading. The installation offset value is a fixed quantified offset value between the preset actual installation position of the laser sensor and the preset theoretical installation position. The method for setting the installation offset value is as follows: First, the three-dimensional rectangular crystal coordinate system constructed by the silicon carbide crystal diameter expansion process is used as a unified spatial reference to determine the theoretical installation position of the laser sensor in the process and calibrate its coordinate parameters. Then, the laser sensor is installed in the installation area of ​​the processing station according to the process requirements. The spatial coordinates of the actual installation position of the sensor are obtained by a high-precision position detection device. Subsequently, the difference between the actual installation position coordinates and the theoretical installation position coordinates is calculated to obtain the offset quantization value between the actual and theoretical installation positions of the sensor. This quantization value is fixed as the installation offset value.

[0047] It should be noted that the calculation formula for the above-mentioned actual measured values ​​in this invention is a quantitative formula for calculating the actual offset distance of the coarse positioning main jet nozzle by combining geometric trigonometric function relationships and installation deviation compensation. This formula uses the optimal nozzle angle as the geometric calculation benchmark and expands the calculation by combining the geometric relationship of the right triangle formed by the jet direction of the main jet nozzle and the vertical distance to the detection. In this right triangle, the optimal nozzle angle is the corresponding acute angle, the vertical distance from the laser sensor to the coarse positioning main jet nozzle is the length of the opposite side of this acute angle, and the basic horizontal distance of the coarse positioning main jet nozzle is the length of the adjacent side of this acute angle. Based on the fundamental relationship that the tangent function of a right triangle is the opposite side divided by the adjacent side, the length of the adjacent side, i.e., the basic horizontal distance, can be derived as follows: This step involves converting the measured vertical distance into a horizontal base distance related to the offset distance through geometric calculations. Since there is a fixed installation offset between the actual and theoretical installation positions of the laser sensor, this offset will affect the horizontal distance measurement results. Therefore, after obtaining the horizontal base distance, this installation offset value needs to be subtracted to accurately compensate for the sensor installation deviation and eliminate the measurement error caused by the installation deviation. The final value obtained is the actual measured value of the coarse positioning main jet nozzle's actual offset distance. This formula, through the aforementioned geometric calculations combined with deviation compensation, eliminates the geometric measurement deviation caused by the nozzle angle and offsets the systematic error caused by the laser sensor installation offset. This achieves accurate calculation of the actual offset distance of the coarse positioning main jet nozzle, providing accurate quantitative data for subsequent deviation calculations between this actual measured value and the negative offset distance, and for determining whether the offset distance of the coarse positioning main jet nozzle meets the process accuracy requirements.

[0048] It should be noted that, since the offset distance adjustment of the main jet nozzle in this invention only revolves around the horizontal axis of the three-dimensional rectangular crystal coordinate system, and the vertical axis is the fixed working position, the position of the main jet nozzle in the vertical axis direction has been accurately positioned in the early stage and there is no need for adjustment throughout the process. The installation of the laser sensor has also been accurately calibrated with the fixed position of the vertical axis as the reference, and there is no installation offset in the vertical axis direction. However, the laser sensor may have a fixed offset value in the horizontal direction corresponding to the horizontal axis due to the installation operation. This fixed offset value will change the actual measurement reference of the laser sensor on the horizontal axis, thereby affecting the basic horizontal distance obtained by geometric calculation, and ultimately causing the deviation of the actual offset distance measurement value. Therefore, this invention needs to compensate for the installation deviation of the measurement results in the horizontal direction.

[0049] S8. Based on the calibration of the main jet nozzle, laser and auxiliary jet nozzle, the fixed silicon carbide crystal is subjected to crystal diameter expansion control operation to obtain the expanded silicon carbide crystal.

[0050] In detail, the process of performing crystal diameter expansion control on a fixed silicon carbide crystal based on calibrating the main jet nozzle, laser, and auxiliary jet nozzle to obtain a diameter-expanded silicon carbide crystal includes: The surface feature points of the silicon carbide crystal are identified to obtain the starting position of the diameter expansion center. Based on the starting position of the diameter expansion center, the laser is positioned and controlled to obtain the positioned laser. A power gradient set is set up, and based on the positioned laser, the calibrated main nozzle, the auxiliary nozzle, and the power gradient set, a crystal diameter expansion control operation is performed on the fixed silicon carbide crystal to obtain a silicon carbide crystal with expanded diameter.

[0051] It should be explained that the step of identifying surface feature points on the fixed silicon carbide crystal is as follows: Using industrial vision recognition equipment or laser 3D scanning and detection equipment, a comprehensive scan of the surface of the area to be expanded on the fixed silicon carbide crystal is performed. Through the equipment's built-in feature extraction algorithm (such as the Harris corner detection algorithm or the Canny algorithm), feature points (such as the geometric center point, edge reference point, or preset marker point of the crystal's area to be expanded) are accurately extracted from the scanned crystal surface contour, texture, and geometric point information. The starting position of the expansion center is the starting point of the expansion processing center for the area to be expanded on the silicon carbide crystal, determined after identifying the surface feature points. Positioning and control is the precise adjustment and fixing of the laser's emitting end spatial position and laser emission angle, using the starting position of the expansion center as a spatial reference and combining the coordinate parameters of the three-dimensional rectangular crystal coordinate system. The purpose of positioning and control is to ensure that the laser beam of the laser is precisely aligned with the starting position of the expansion center on the fixed silicon carbide crystal, ensuring that the laser heating energy accurately acts on the area to be expanded. The positioned laser is a laser whose beam, after positioning and adjustment, can precisely target the starting position of the diameter expansion center of a pre-fixed silicon carbide crystal. The power gradient set is a pre-set set of laser power values ​​arranged in ascending order. For example, the power gradient set might be {5W, 8W, 12W, 15W}. The power gradient set allows for step-wise adjustment of the laser power output, providing laser heating energy suitable for different processing stages during crystal diameter expansion. The detailed steps for controlling the diameter expansion of the pre-fixed silicon carbide crystal using the positioned laser, calibrated main and secondary nozzles, and the power gradient set will be provided later.

[0052] In detail, the crystal diameter expansion control operation performed on the fixed silicon carbide crystal based on the positioned laser, the calibrated main nozzle, the secondary nozzle, and the power gradient set to obtain the expanded silicon carbide crystal includes: The first power gradient is extracted from the power gradient set, and the target number of revolutions parameters are determined based on the first power gradient. The target number of revolutions parameters include: scanning speed and helix spacing. The power of the located laser is set based on the first power gradient and the target number of cycles to obtain the first laser. The fixed silicon carbide crystal was simultaneously scanned using the first laser, the secondary jet nozzle, and the calibration main jet nozzle to obtain the preliminary diameter-expanded crystal, the crystal center point temperature, the scanning front temperature, and the temperature of the processed area. The average temperature of the crystal is obtained by weighted summing of the temperature at the crystal center point, the temperature at the scanning front edge, and the temperature of the processed area. The updated power gradient is obtained by performing power regulation operation based on the average temperature of the crystal. The updated power gradient is used as the first power gradient, and the initially expanded crystal is used as the fixed silicon carbide crystal. The process is repeated until the updated power gradient equals the preset end power gradient. The updated power gradients are summarized to obtain the updated power gradient set, and the expanded silicon carbide crystal is identified based on the updated power gradient set.

[0053] It should be explained that the power gradient is the laser power value extracted from the power gradient set and used for processing the fixed silicon carbide crystal. The scanning speed is the linear velocity of the laser beam emitted by the laser as it scans the surface of the silicon carbide crystal in the area to be expanded. The helical spacing is the distance between two adjacent helical scanning trajectories when the laser and the calibration main nozzle process the crystal in a helical scanning manner. The first laser is the laser whose output power is set according to the extracted power gradient, and whose scanning parameters are matched with the scanning speed and helical spacing in the target number of revolutions. The specific operational steps for simultaneously scanning the silicon carbide crystal using the first laser and the calibration main nozzle to obtain the initial expanded crystal, the crystal center temperature, the scanning front temperature, and the processed area temperature will be given later. The first power gradient is the first power gradient in the power gradient set. The last power gradient is the last power gradient in the power gradient set.

[0054] For example, the power gradient set is {5W, 8W, 12W, 15W}. The first power gradient is identified as 5W from the power gradient set. The diameter of the fixed silicon carbide crystal is expanded using the first power gradient, and the average temperature of the crystal is calculated after the diameter expansion. When the average temperature of the crystal is not greater than the upper limit of the ending temperature and not less than the lower limit of the ending temperature, the current average temperature of the crystal is considered to be qualified. At this time, the second power of 8W is no longer adjusted, and the second power of 8W is recorded as the updated power gradient. Otherwise, the current average temperature of the crystal is considered to be unqualified, which will damage the crystal during the diameter expansion. Therefore, the present invention adjusts the second power to obtain the updated power gradient, uses the updated power gradient as the first power gradient, and returns to the step of identifying the target number of cycles based on the first power gradient. The steps of the first power gradient are executed until the updated power gradient is equal to the final power gradient of 15W, and the above loop operation is stopped.

[0055] Importantly, the step of weighted summation of the crystal center point temperature, scanning front temperature, and processed area temperature involves: setting corresponding process weighting coefficients for the crystal center point temperature, scanning front temperature, and processed area temperature (the weighting coefficients are determined based on the influence of each temperature index on the diameter expansion effect; the greater the influence, the higher the coefficient, and the sum of all coefficients is 1); multiplying each temperature value by its corresponding weighting coefficient to obtain the weighted value of each temperature; and finally summing the weighted values ​​of the three temperatures. The crystal average temperature is the temperature value obtained by weighted summation of the crystal center point temperature, scanning front temperature, and processed area temperature. The updated power gradient is the new laser power value obtained after adjusting the original extracted power gradient based on the crystal average temperature. The updated power gradient set is a collection composed of updated power gradients. The expanded silicon carbide crystal is the silicon carbide crystal obtained after extracting all power gradients from the power gradient set round by round and completing all synchronous scanning and power adjustment operations. The detailed steps of power adjustment based on the crystal average temperature to obtain the updated power gradient will be given later.

[0056] It should be noted that in the above steps of this invention, since the heating energy and effect corresponding to different laser powers are different, it is necessary to match the scanning motion parameters such as scanning speed and helical spacing to ensure the uniformity of laser heating and the crystal diameter expansion effect. Therefore, this invention determines the target number of revolutions based on the extracted power gradient. The purpose is to make the laser power and scanning rhythm accurately matched, so as to avoid problems such as excessive or insufficient local heating of crystal, diameter expansion size deviation, and irregular forming surface caused by mismatch between power and scanning parameters. Secondly, a laser beam of set power is emitted by a laser to heat the area of ​​the silicon carbide crystal to be expanded, thereby expanding the crystal diameter. At the same time, the main nozzle of the calibration system synchronously sprays argon gas along the laser scanning trajectory. The argon gas is used to protect and assist in the shaping of the processing area, ensuring the quality of the diameter expansion process. During the synchronous scanning process, the temperature of the core area of ​​the crystal diameter expansion (i.e., the area currently being acted upon by the laser beam), the processing front area (the area to be processed that will be scanned by the laser), and the processed area (i.e., the area that has been scanned by the laser beam and has completed the diameter expansion deformation) is monitored in real time by a temperature detection device. This accurately obtains the temperature data of different areas during the processing. While completing a single round of laser heating and diameter expansion, the real-time temperature status of different processing parts of the crystal can be comprehensively collected. This not only realizes the basic diameter expansion operation, but also provides a comprehensive temperature data basis for subsequent dynamic control of laser power. The collected temperatures at the crystal center point, scanning front, and processed area are integrated using a weighted summation method. This comprehensively considers the influence of different temperature regions on the overall diameter expansion effect of the fixed silicon carbide crystal, calculating the average crystal temperature that reflects the overall temperature level of the diameter expansion region. This method effectively avoids the one-sidedness of temperature data from a single region and eliminates the drawback of local temperatures failing to characterize the overall heating state of the fixed silicon carbide crystal. It comprehensively reflects the current overall heating state of the fixed silicon carbide crystal, providing reliable data support for subsequent laser power adjustment. Based on the calculated average crystal temperature, it is compared with the preset optimal temperature range for crystal diameter expansion. According to the deviation between the actual average temperature and the optimal temperature range, the laser power is dynamically adjusted accordingly. This ensures that the laser power matches the current actual temperature state of the crystal, promptly correcting temperature deviations caused by excessively high or low power, and ensuring that the heating temperature of the crystal diameter expansion region remains stable within the optimal range required by the process during subsequent scanning and processing.The adjusted updated power gradient is used as the new processing power, and the initially expanded crystal is used as the new processing substrate. The corresponding scanning parameters are matched again and synchronous scanning processing is carried out. Through such a closed-loop operation, the expansion processing corresponding to all power gradients in the power gradient concentration is completed round by round. In each round of processing, the laser power is adapted and controlled, and the laser power is dynamically optimized throughout the process. This ensures that the laser power in the entire silicon carbide crystal expansion process is always matched with the real-time temperature state and processing progress of the silicon carbide crystal, effectively improving the dimensional accuracy and forming quality of the crystal expansion, and ensuring that the expansion effect meets the preset process requirements.

[0057] In detail, the simultaneous scanning operation of the fixed silicon carbide crystal using a first laser, a secondary jet nozzle, and a calibration main jet nozzle to obtain the preliminary diameter-expanded crystal, the crystal center point temperature, the scanning front temperature, and the processed area temperature includes: The flow rate of the argon gas is controlled by the pre-constructed flow control system to obtain the main nozzle of the gas to be sprayed. The gas flow rate of the main nozzle of the gas to be sprayed is controlled to obtain the gas flow field environment. Based on the gas flow field environment, the first laser and the secondary jet nozzle are used to perform synchronous processing operations on the fixed silicon carbide crystal to obtain the initial diameter-expanded crystal. Temperature data was collected from the initial expanded crystal to obtain the temperature at the crystal center point, the scanning front temperature, and the temperature of the processed area.

[0058] It should be explained that the flow control system is a control system used to precisely regulate and adjust the argon output flow of the calibration main nozzle. The main nozzle to be sprayed is the main nozzle in a state where the argon flow rate meets the standard and can spray argon at any time after the calibration main nozzle has completed the argon flow rate setting and control through the flow control system. The steps of gas flow control operation of the main nozzle to be sprayed are as follows: the actual argon output flow of the main nozzle to be sprayed is monitored in real time through the flow control system, and the measured flow rate is compared with the process preset flow rate. If there is a deviation, the argon flow rate is dynamically fine-tuned through the control system in a timely manner to ensure that the main nozzle to be sprayed continuously and stably outputs the preset flow rate of argon. At the same time, the argon acts on the silicon carbide crystal to be expanded area, and finally forms a stable, uniform gas flow field environment in the crystal processing area that is adapted to the expansion process requirements. The gas flow field environment is the environment formed in and around the silicon carbide crystal to be expanded area after the main nozzle to be sprayed performs precise gas flow control operation. The steps for obtaining an initial diameter-expanded crystal by simultaneously processing a fixed silicon carbide crystal using a first laser and a secondary nozzle based on a gas flow field environment are as follows: First, the spot of the first laser is focused on the starting position of the diameter expansion center on the surface of the fixed silicon carbide crystal. Second, the first laser is started to perform a circular spiral scan from the inside out according to the extracted power gradient and scanning parameters (including scanning speed and spiral spacing). At the same time, the secondary nozzle is started synchronously, so that the secondary nozzle sprays argon gas with a pulse frequency and pulse width that matches the laser scanning cycle. The main nozzle provides a continuous and stable laminar argon gas to form a basic protective atmosphere covering the processing area, while the pulsed airflow of the secondary nozzle generates an instantaneously enhanced airflow disturbance near the laser action point, which works in conjunction with the main airflow to remove gaseous products and micro-debris generated during processing. During this process, the laser energy causes the silicon carbide material to undergo thermal decomposition and vaporization, and the pulsed airflow assists in removing products and inhibiting oxidation. Through a spiral scanning path that expands successively over multiple turns, a circular diameter-expanded structure with diameter and depth is finally formed on the surface of the fixed silicon carbide crystal, thus obtaining the initial diameter-expanded crystal.

[0059] Understandably, the temperature data acquisition for the initial diameter-expanding crystal is performed using a non-contact temperature detection device. Using the starting position of the diameter-expanding center of the fixed silicon carbide crystal as the detection reference, the detection points of the device are precisely aligned with the diameter-expanding center of the initial diameter-expanding crystal, the unprocessed area at the leading edge of the laser scanning trajectory, and the processed area where the laser has completed scanning. The temperature values ​​of these three areas are captured and recorded in real time by the non-contact temperature detection device. The crystal center point temperature, the scanning leading edge temperature, and the processed area temperature are respectively the real-time temperature of the starting position of the diameter-expanding center of the initial diameter-expanding crystal, the real-time temperature of the unprocessed area to be heated by the laser, and the real-time temperature of the processed area that has completed scanning. Detecting the crystal center point temperature directly reflects the heating intensity and temperature stability of the diameter-expanding core area and is a key basis for determining whether the laser base power is suitable for the heating requirements of the crystal core area. If the temperature in this area is too high or too low, it will directly affect the diameter-expanding effect of the crystal core. Detecting the temperature at the scanning front edge reflects the preheating state of the unprocessed area and the temperature transition between the processed and unprocessed areas. This helps determine the compatibility of the laser scanning rhythm and power with the temperature of the unprocessed area of ​​the crystal, preventing sudden temperature changes and stress cracks caused by excessively low front edge temperatures during laser heating, or excessively high front edge temperatures leading to overheating and affecting diameter expansion accuracy. Detecting the temperature of the processed area reflects the residual heat decay after processing. Combined with the purging operation of the secondary nozzle, the cooling and heat preservation effects of the purging can be evaluated. If the temperature in this area drops too quickly, it can easily lead to uneven shrinkage and dimensional deviations after crystal forming. If the temperature is too high, it may cause secondary heating of the crystal and loss of control over the diameter expansion morphology.

[0060] In detail, the power regulation operation based on the average temperature of the crystal to obtain the updated power gradient includes: Adjacent power gradients are identified from the power gradient set based on the first-order power gradient. If the average temperature of the crystal is greater than the preset end temperature limit, then the power reduction operation is performed on the adjacent power gradient to obtain the first controlled power gradient. If the average temperature of the crystal is less than the preset lower limit of the end temperature, then the power gradient of the adjacent power gradient is increased to obtain the second controlled power gradient. If the average crystal temperature is not greater than the upper limit of the termination temperature and not less than the lower limit of the termination temperature, then the adjacent power gradients are taken as the optimal power gradients. The updated power gradient is determined based on the first controlled power gradient, the second controlled power gradient, or the optimal power gradient.

[0061] It should be explained that the adjacent power gradient is determined by arranging the currently extracted power gradient used for processing in ascending order, and identifying the next adjacent laser power gradient. If the average crystal temperature exceeds the preset end temperature limit, it indicates that after processing with the current power gradient, the overall average temperature of the crystal expansion region exceeds the end temperature limit, and the silicon carbide crystal is in an overheated state. Continuing to process with the original power or adjacent power can easily lead to excessive thermal stress, cracking, and uncontrolled expansion of the silicon carbide crystal, requiring a downward adjustment of the power gradient. The end temperature limit is a preset threshold for the maximum overall average temperature of the crystal expansion region during the silicon carbide crystal expansion process. The power reduction operation for adjacent power gradients is performed using a preset fixed power reduction value (e.g., 50W). The first adjusted power gradient is the power gradient obtained after performing the power reduction operation on the adjacent power gradients. If the average crystal temperature is lower than the preset lower limit of the end temperature, it means that after processing with the current power gradient, the overall average temperature of the crystal expansion region is lower than the lower limit of the end temperature. The silicon carbide crystal is in a state of insufficient heating. Continuing to process at the original power or adjacent power will lead to problems such as slow expansion of the silicon carbide crystal, substandard expansion dimensions, and non-dense crystal structure. Therefore, the power needs to be increased. The lower limit of the end temperature is a preset threshold value representing the minimum overall average temperature of the crystal expansion region during the silicon carbide crystal expansion process. The power increase adjustment operation for adjacent power gradients involves quantitatively increasing the power of the adjacent power gradient using a preset fixed power increase value (e.g., 30W). The second power gradient adjustment is the power gradient obtained after increasing the power of the adjacent power gradients. The optimal power gradient is the adjacent power gradient where the average crystal temperature is not greater than the upper limit of the end temperature or not less than the lower limit of the end temperature.

[0062] It should be noted that the upper and lower limits of the termination temperature are set as follows: First, based on the inherent material properties of silicon carbide crystals, such as melting point, coefficient of thermal expansion, and thermal stress tolerance threshold, combined with the forming requirements of laser heating diameter expansion and the target crystal diameter expansion size, a basic control range for the overall average temperature of the crystal diameter expansion region is initially defined. The initial values ​​of the upper and lower limits of the termination temperature are then determined. The initial value of the upper limit of the termination temperature is lower than the critical temperature for crystal thermal deformation and thermal cracking, while the initial value of the lower limit of the termination temperature is higher than the minimum heating temperature at which effective diameter expansion cannot be achieved for silicon carbide crystals. Then, a simulation model of silicon carbide crystal laser diameter expansion is built using process simulation software. Different power gradients and scanning parameters are input to simulate the crystal diameter expansion process in different temperature ranges, and the carbonization process is analyzed. The molding effect, thermal stress distribution, and diameter expansion accuracy of silicon crystals at different temperatures were investigated. Based on simulation results, the initial upper and lower limits of the ending temperature were optimized and adjusted to eliminate temperature thresholds that could lead to diameter expansion defects and narrow the temperature control accuracy range. Subsequently, multiple sets of actual diameter expansion process experiments of silicon carbide crystals were carried out. Laser heating processing was performed according to the optimized temperature thresholds, and the average temperature of the crystal and the corresponding diameter expansion molding data were collected in real time to verify the diameter expansion quality of the crystal under different upper and lower temperature limits. It was particularly important to confirm that the silicon carbide crystals did not experience thermal cracking or thermal deformation at the upper end temperature and that the crystals could achieve stable diameter expansion molding at the lower end temperature. Based on the experimental results, the temperature thresholds were precisely calibrated to determine the upper and lower limits of the ending temperature suitable for actual processing.

[0063] In detail, the formula for calculating the first controlled power gradient is as follows: , in, This represents the first control power gradient. Indicates the adjacent power gradient, This represents the natural exponential function. Indicates the average temperature of the crystal. Indicates the upper limit of the end temperature. This indicates the preset thermal inertia compensation temperature.

[0064] It should be explained that the thermal inertia compensation temperature is a fixed compensation parameter pre-calibrated based on the thermophysical properties of silicon carbide crystals, the heat conduction law of laser processing, and the requirements of the diameter expansion process. It is used to quantitatively compensate for the hysteresis deviation between temperature detection and power control caused by the thermal inertia of the silicon carbide crystal during laser heating. The calculation formula for the first controlled power gradient in this invention utilizes the nonlinear variation characteristics of the natural exponential curve to make the power reduction magnitude nonlinearly related to the difference between the average crystal temperature and the upper limit of the final temperature. The greater the temperature exceedance, the greater the power reduction magnitude. Simultaneously, the thermal inertia compensation temperature offsets the control hysteresis problem caused by the thermal inertia of the silicon carbide crystal, thereby achieving precise and nonlinear power reduction control of adjacent power gradients. This ensures that the obtained first controlled power gradient can adapt to the actual degree of overheating of the silicon carbide crystal and compensates for the control deviation caused by thermal inertia, avoiding the limitations of a single fixed value reduction. This guarantees precise matching between the laser power and the actual temperature state of the crystal, preventing problems such as thermal cracking and uncontrolled molding caused by continuous overheating of the silicon carbide crystal.

[0065] S9. Based on the expanded silicon carbide crystal, complete the expansion of silicon carbide crystal using laser-assisted heating.

[0066] It should be noted that this invention completes the entire process of laser-assisted heating silicon carbide crystal diameter expansion, verifies the effectiveness of the whole process control operation, and finally obtains silicon carbide crystals with diameter expansion size, forming quality and other properties that meet the process preset requirements, thus achieving the diameter expansion processing target set by the process.

[0067] To address the problems described in the background art, this invention identifies the silicon carbide crystal, laser, main nozzle, and auxiliary nozzle, fixes the silicon carbide crystal to obtain a fixed silicon carbide crystal, and sets gas-assisted parameters, including the target blowing angle, negative offset distance, and argon flow rate. This invention ensures the stability of the crystal's spatial position during all subsequent processing and control operations by fixing it, avoiding processing deviations and inaccurate positioning caused by crystal displacement. Based on the fixed silicon carbide crystal, the processing starting point position is determined, and a three-dimensional Cartesian crystal coordinate system is constructed based on this starting point position. This three-dimensional Cartesian crystal coordinate system is used for subsequent laser positioning, nozzle angle adjustment, and offset distance adjustment. This invention provides a unified spatial reference for all spatial location-related operations, enabling precise spatial positioning throughout the entire processing flow and eliminating control deviations caused by inconsistent spatial references. Based on the target blowing angle in the main jet nozzle and gas auxiliary parameters, the nozzle angle is adjusted to obtain an adjusted main jet nozzle. This invention adjusts the blowing angle of the main jet nozzle to the target value preset by the process, allowing the argon gas injection direction of the main jet nozzle to initially adapt to the gas requirements of the crystal diameter expansion processing area. Based on the adjusted main jet nozzle, gas flow field testing and control are performed on the fixed silicon carbide crystal to obtain the optimal nozzle angle. This invention verifies and optimizes the blowing angle of the main jet nozzle through actual flow field testing, confirming that it can form a stable and adaptable flow field in the crystal processing area for diameter expansion. This invention optimizes the nozzle angle for the gas flow field, avoiding problems such as flow field disturbance and poor argon protection caused by unreasonable angles. It corrects the nozzle angle of the pre-adjusted main jet nozzle using the optimal nozzle angle, resulting in an optimal main jet nozzle. This precise correction of the main jet nozzle angle to its optimal value enables it to stably output the optimal gas flow field, providing a precisely angled nozzle for subsequent offset distance control. The offset distance of the optimal main jet nozzle is then controlled based on a three-dimensional Cartesian crystal coordinate system, resulting in a calibrated main jet nozzle. This invention achieves precise control of the main jet nozzle offset distance using a unified spatial reference, ensuring that the spatial relative position of the main jet nozzle and the crystal processing area matches the process requirements. By optimizing the nozzle angle, the calibrated jet nozzle can create an argon gas environment with optimal position, angle, and flow field in the crystal processing area. Based on the calibrated main jet nozzle, laser, and auxiliary jet nozzle, crystal diameter expansion control is performed on the fixed silicon carbide crystal to obtain an expanded silicon carbide crystal. This invention relies on the optimal gas flow field support of the calibrated jet nozzle, combined with the laser to complete the entire process control of crystal diameter expansion, achieving precise synergy between laser heating and argon assistance. This ensures the dimensional accuracy and forming quality of the crystal diameter expansion, avoiding problems such as crystal oxidation, thermal cracking, and irregular forming caused by insufficient gas assistance, resulting in an expanded crystal that meets the process requirements. Based on the expanded silicon carbide crystal, laser-assisted heating is used to complete the diameter expansion of silicon carbide crystals. Therefore, this invention can achieve dynamic and precise control of the thermal field and real-time adaptation and adjustment of gas phase transport and composition during the diameter expansion process.

[0068] like Figure 2 The diagram shown is a functional block diagram of a silicon carbide crystal diameter expansion system based on laser-assisted heating provided in an embodiment of the present invention.

[0069] The laser-assisted heating silicon carbide crystal diameter expansion system 100 described in this invention can be installed in an electronic device. Depending on the functions implemented, the laser-assisted heating silicon carbide crystal diameter expansion system 100 may include a parameter setting module 101, a nozzle angle control module 102, a crystal diameter expansion control module 103, and a crystal diameter expansion control completion module 104. The module described in this invention can also be called a unit, referring to a series of computer program segments that can be executed by the processor of an electronic device and perform a fixed function, stored in the memory of the electronic device. The control parameter setting module 101 is used to identify the silicon carbide crystal, laser, main nozzle and auxiliary nozzle, fix the silicon carbide crystal to obtain a fixed silicon carbide crystal, and set gas auxiliary parameters, including: target blowing angle, negative bias distance and argon flow rate. The nozzle angle control module 102 is used to determine the processing start position based on the fixed silicon carbide crystal, construct a three-dimensional rectangular crystal coordinate system based on the processing start position, perform nozzle angle control operation based on the target blowing angle in the main jet nozzle and gas auxiliary parameters to obtain the adjusted main jet nozzle, perform gas flow field test and control on the fixed silicon carbide crystal based on the adjusted main jet nozzle to obtain the optimal nozzle angle, perform nozzle angle correction operation on the adjusted main jet nozzle using the optimal nozzle angle to obtain the optimal angle main jet nozzle, and perform offset distance control on the optimal angle main jet nozzle based on the three-dimensional rectangular crystal coordinate system to obtain the calibrated main jet nozzle; The crystal diameter expansion control module 103 is used to perform crystal diameter expansion control operation on the fixed silicon carbide crystal based on the calibration of the main jet nozzle, laser and auxiliary jet nozzle, so as to obtain the expanded silicon carbide crystal. The crystal diameter expansion control module 104 is used to complete the diameter expansion of a silicon carbide crystal based on laser-assisted heating, using an already expanded silicon carbide crystal. Specifically, in this embodiment of the invention, each module in the laser-assisted heating silicon carbide crystal diameter expansion system 100 employs the same methods as described above. Figure 1 The method described herein is the same as the laser-assisted heating-based silicon carbide crystal diameter expansion method and can produce the same technical effect, so it will not be repeated here.

[0070] like Figure 3 The diagram shown is a schematic representation of an electronic device for implementing a laser-assisted heating method for expanding the diameter of silicon carbide crystals, according to an embodiment of the present invention.

[0071] The electronic device 1 may include a processor 10, a memory 11 and a bus 12, and may also include a computer program stored in the memory 11 and executable on the processor 10, such as a program for a method of expanding the diameter of silicon carbide crystals based on laser-assisted heating.

[0072] The memory 11 includes at least one type of readable storage medium, such as flash memory, portable hard drive, multimedia card, card-type memory (e.g., SD or DX memory), magnetic memory, magnetic disk, optical disk, etc. In some embodiments, the memory 11 can be an internal storage unit of the electronic device 1, such as the portable hard drive of the electronic device 1. In other embodiments, the memory 11 can be an external storage device of the electronic device 1, such as a plug-in portable hard drive, smart media card (SMC), secure digital card (SD), flash card, etc., equipped on the electronic device 1. Furthermore, the memory 11 includes both internal storage units and external storage devices of the electronic device 1. The memory 11 can be used not only to store application software and various types of data installed on the electronic device 1, such as the code of a laser-assisted heating silicon carbide crystal diameter expansion method program, but also to temporarily store data that has been output or will be output.

[0073] In some embodiments, the processor 10 may be composed of integrated circuits, such as a single packaged integrated circuit or multiple integrated circuits with the same or different functions, including combinations of one or more central processing units (CPUs), microprocessors, digital processing chips, graphics processors, and various control chips. The processor 10 is the control unit of the electronic device, connecting various components of the entire electronic device through various interfaces and lines. It executes programs or modules stored in the memory 11 (e.g., a program for a silicon carbide crystal diameter expansion method based on laser-assisted heating) and calls data stored in the memory 11 to perform various functions of the electronic device 1 and process data.

[0074] The bus 12 can be a peripheral component interconnect (PCI) bus or an extended industry standard architecture (EISA) bus, etc. The bus 12 can be divided into an address bus, a data bus, a control bus, etc. The bus 12 is configured to realize the connection and communication between the memory 11 and at least one processor 10, etc.

[0075] Figure 3 Only electronic devices with components are shown; it will be understood by those skilled in the art that... Figure 3 The structure shown does not constitute a limitation on the electronic device 1, and may include fewer or more components than shown, or combine certain components, or have different component arrangements.

[0076] For example, although not shown, the electronic device 1 may also include a power supply (such as a battery) to power the various components. Preferably, the power supply can be logically connected to the at least one processor 10 through a power management device, thereby enabling functions such as charging management, discharging management, and power consumption management. The power supply may also include one or more DC or AC power supplies, recharging devices, power fault detection circuits, power converters or inverters, power status indicators, and other arbitrary components. The electronic device 1 may also include various sensors, Bluetooth modules, Wi-Fi modules, etc., which will not be described in detail here.

[0077] Furthermore, the electronic device 1 may also include a network interface. Optionally, the network interface may include a wired interface and / or a wireless interface (such as a Wi-Fi interface, a Bluetooth interface, etc.), which is typically used to establish communication connections between the electronic device 1 and other electronic devices.

[0078] Optionally, the electronic device 1 may further include a user interface, which may be a display, an input unit (such as a keyboard), and optionally, a standard wired interface or a wireless interface. Optionally, in some embodiments, the display may be an LED display, a liquid crystal display, a touch-sensitive liquid crystal display, or an OLED (Organic Light-Emitting Diode) touchscreen, etc. The display may also be appropriately referred to as a screen or display unit, used to display information processed in the electronic device 1 and to display a visual user interface.

[0079] The program for the laser-assisted heating silicon carbide crystal diameter expansion method stored in the memory 11 of the electronic device 1 is a combination of multiple instructions. When run in the processor 10, it can achieve the following: The silicon carbide crystal, laser, main nozzle and auxiliary nozzle were identified, and the silicon carbide crystal was fixed to obtain a fixed silicon carbide crystal. Set the gas-assisted parameters, which include: target blowing angle, negative offset distance, and argon flow rate; The processing start point position is determined based on the fixed silicon carbide crystal, and a three-dimensional rectangular crystal coordinate system is constructed based on the processing start point position; Based on the target blowing angle in the main jet nozzle and gas auxiliary parameters, the nozzle angle is adjusted to obtain the adjusted main jet nozzle; Based on the adjusted main jet nozzle, the gas flow field of the fixed silicon carbide crystal was tested and controlled to obtain the optimal nozzle angle; The nozzle angle of the adjusted main jet nozzle is corrected using the optimal nozzle angle to obtain the optimal main jet nozzle angle. The offset distance of the optimal angle main jet nozzle is adjusted based on a three-dimensional rectangular crystal coordinate system to obtain a calibrated main jet nozzle. Based on the calibration of the main jet nozzle, laser and auxiliary jet nozzle, crystal diameter expansion control operation is performed on the fixed silicon carbide crystal to obtain the expanded silicon carbide crystal; Laser-assisted heating was used to expand the diameter of silicon carbide crystals based on the expanded diameter silicon carbide crystals.

[0080] Specifically, the processor 10's implementation method for the above instructions can be found in [reference needed]. Figures 1 to 3 The descriptions of the relevant steps in the corresponding embodiments are not repeated here.

[0081] Furthermore, if the modules / units integrated in the electronic device 1 are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. The computer-readable storage medium can be volatile or non-volatile. For example, the computer-readable medium may include: any entity or device capable of carrying the computer program code, a recording medium, a USB flash drive, a portable hard drive, a magnetic disk, an optical disk, a computer memory, or a read-only memory (ROM).

[0082] The present invention also provides a computer-readable storage medium storing a computer program, which, when executed by a processor of an electronic device, can perform the following: The silicon carbide crystal, laser, main nozzle and auxiliary nozzle were identified, and the silicon carbide crystal was fixed to obtain a fixed silicon carbide crystal. Set the gas-assisted parameters, which include: target blowing angle, negative offset distance, and argon flow rate; The processing start point position is determined based on the fixed silicon carbide crystal, and a three-dimensional rectangular crystal coordinate system is constructed based on the processing start point position; Based on the target blowing angle in the main jet nozzle and gas auxiliary parameters, the nozzle angle is adjusted to obtain the adjusted main jet nozzle; Based on the adjusted main jet nozzle, the gas flow field of the fixed silicon carbide crystal was tested and controlled to obtain the optimal nozzle angle; The nozzle angle of the adjusted main jet nozzle is corrected using the optimal nozzle angle to obtain the optimal main jet nozzle angle. The offset distance of the optimal angle main jet nozzle is adjusted based on a three-dimensional rectangular crystal coordinate system to obtain a calibrated main jet nozzle. Based on the calibration of the main jet nozzle, laser and auxiliary jet nozzle, crystal diameter expansion control operation is performed on the fixed silicon carbide crystal to obtain the expanded silicon carbide crystal; Laser-assisted heating was used to expand the diameter of silicon carbide crystals based on the expanded diameter silicon carbide crystals.

[0083] In the embodiments provided by this invention, it should be understood that the disclosed devices, systems, and methods can be implemented in other ways. For example, the system embodiments described above are merely illustrative, and actual implementations may have other classification methods.

[0084] The modules described as separate components may or may not be physically separate. The components shown as modules may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0085] Furthermore, the functional modules in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or in the form of hardware plus software functional modules.

[0086] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention.

[0087] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for expanding the diameter of silicon carbide crystals based on laser-assisted heating, characterized in that, The method includes: The silicon carbide crystal, laser, main nozzle and auxiliary nozzle were identified, and the silicon carbide crystal was fixed to obtain a fixed silicon carbide crystal. Set the gas-assisted parameters, which include: target blowing angle, negative offset distance, and argon flow rate; The processing start point position is determined based on the fixed silicon carbide crystal, and a three-dimensional rectangular crystal coordinate system is constructed based on the processing start point position; Based on the target blowing angle in the main jet nozzle and gas auxiliary parameters, the nozzle angle is adjusted to obtain the adjusted main jet nozzle; Based on the adjusted main jet nozzle, the gas flow field of the fixed silicon carbide crystal was tested and controlled to obtain the optimal nozzle angle; The nozzle angle of the adjusted main jet nozzle is corrected using the optimal nozzle angle to obtain the optimal main jet nozzle angle. The offset distance of the optimal angle main jet nozzle is adjusted based on a three-dimensional rectangular crystal coordinate system to obtain a calibrated main jet nozzle. Based on the calibration of the main jet nozzle, laser and auxiliary jet nozzle, crystal diameter expansion control operation is performed on the fixed silicon carbide crystal to obtain the expanded silicon carbide crystal; Laser-assisted heating was used to expand the diameter of silicon carbide crystals based on the expanded diameter silicon carbide crystals.

2. The method for expanding the diameter of silicon carbide crystals based on laser-assisted heating as described in claim 1, characterized in that, The nozzle angle adjustment operation based on the target blowing angle in the main jet nozzle and gas auxiliary parameters to obtain the adjusted main jet nozzle includes: The initial angle of the main jet nozzle is measured to obtain the initial measurement angle. The angle adjustment amount is calculated based on the target blowing angle in the gas auxiliary parameters and the initial measurement angle. If the angle adjustment amount is greater than the preset zero value, the angle of the main jet nozzle is increased according to the preset coarse adjustment step size to obtain the coarse adjustment main jet nozzle; If the angle adjustment amount is less than zero, the main jet nozzle is adjusted by reducing the angle according to the coarse adjustment step size to obtain the coarse adjustment main jet nozzle; The coarse-adjusted main jet nozzle is precisely adjusted until the angle adjustment is equal to zero, thus obtaining the adjusted main jet nozzle.

3. The method for expanding the diameter of silicon carbide crystals based on laser-assisted heating as described in claim 2, characterized in that, The process of adjusting the offset distance of the optimal angle main jet nozzle based on a three-dimensional rectangular crystal coordinate system to obtain a calibrated main jet nozzle includes: The theoretical intersection coordinates are calculated based on the negative offset distance and the three-dimensional rectangular crystal coordinate system. The nozzle axis direction vector is determined based on the optimal nozzle angle corresponding to the optimal angle main jet nozzle. The optimal angle main jet nozzle is height-adjusted based on the nozzle axis direction vector to obtain the standard height main jet nozzle. The standard height main jet nozzle is then moved laterally based on the negative offset distance in the theoretical intersection coordinates to obtain the coarse positioning main jet nozzle. The actual measured value is calculated based on the coarse positioning main jet nozzle, and the deviation is calculated based on the actual measured value and the negative offset distance to obtain the offset difference value; If the offset difference is not within the preset deviation range, the coarse positioning main jet nozzle is laterally adjusted to obtain an adjusted main jet nozzle. The adjusted main jet nozzle is then used as the coarse positioning main jet nozzle. The process is repeated until the offset difference is within the deviation range. If the bias difference is within the deviation range, the adjusted main jet nozzle is used as the calibrated main jet nozzle.

4. The method for expanding the diameter of silicon carbide crystals based on laser-assisted heating as described in claim 3, characterized in that, The calculation of actual measured values ​​based on the coarse positioning main jet nozzle includes: The laser sensor readings are obtained based on the coarse positioning main jet nozzle, and the vertical distance is calculated based on the laser sensor readings and the preset installation offset value. The actual measured value is calculated based on the vertical distance, optimal nozzle angle, and installation offset. The formula for calculating the actual measured value is as follows: ， in, This represents the actual measured value. Indicates vertical distance. Indicates the optimal nozzle angle. Represents the tangent function. This indicates the installation offset value.

5. The method for expanding the diameter of silicon carbide crystals based on laser-assisted heating as described in claim 4, characterized in that, The process of performing crystal diameter expansion control on a fixed silicon carbide crystal based on calibrating the main jet nozzle, laser, and auxiliary jet nozzle to obtain a diameter-expanded silicon carbide crystal includes: The surface feature points of the silicon carbide crystal are identified to obtain the starting position of the diameter expansion center. Based on the starting position of the diameter expansion center, the laser is positioned and controlled to obtain the positioned laser. A power gradient set is set up, and based on the positioned laser, the calibrated main nozzle, the auxiliary nozzle, and the power gradient set, a crystal diameter expansion control operation is performed on the fixed silicon carbide crystal to obtain a silicon carbide crystal with expanded diameter.

6. The method for expanding the diameter of silicon carbide crystals based on laser-assisted heating as described in claim 5, characterized in that, The process of performing crystal diameter expansion control on a fixed silicon carbide crystal based on a positioned laser, a calibrated main nozzle, a secondary nozzle, and a power gradient set to obtain a diameter-expanded silicon carbide crystal includes: The first power gradient is extracted from the power gradient set, and the target number of revolutions parameters are determined based on the first power gradient. The target number of revolutions parameters include: scanning speed and helix spacing. The power of the located laser is set based on the first power gradient and the target number of cycles to obtain the first laser. The fixed silicon carbide crystal was simultaneously scanned using the first laser, the secondary jet nozzle, and the calibration main jet nozzle to obtain the preliminary diameter-expanded crystal, the crystal center point temperature, the scanning front temperature, and the temperature of the processed area. The average temperature of the crystal is obtained by weighted summing of the temperature at the crystal center point, the temperature at the scanning front edge, and the temperature of the processed area. The updated power gradient is obtained by performing power regulation operation based on the average temperature of the crystal. The updated power gradient is used as the first power gradient, and the initially expanded crystal is used as the fixed silicon carbide crystal. The process is repeated until the updated power gradient equals the preset end power gradient. The updated power gradients are summarized to obtain the updated power gradient set, and the expanded silicon carbide crystal is identified based on the updated power gradient set.

7. The method for expanding the diameter of silicon carbide crystals based on laser-assisted heating as described in claim 6, characterized in that, The simultaneous scanning operation of the fixed silicon carbide crystal using a first laser, a secondary jet nozzle, and a calibration main jet nozzle yields preliminary diameter-expanding crystal, crystal center point temperature, scanning front temperature, and processed area temperature, including: The flow rate of the argon gas is controlled by the pre-constructed flow control system to obtain the main nozzle of the gas to be sprayed. The gas flow rate of the main nozzle of the gas to be sprayed is controlled to obtain the gas flow field environment. Based on the gas flow field environment, the first laser and the secondary jet nozzle are used to perform synchronous processing operations on the fixed silicon carbide crystal to obtain the initial diameter-expanded crystal. Temperature data was collected from the initial expanded crystal to obtain the temperature at the crystal center point, the scanning front temperature, and the temperature of the processed area.

8. The method for expanding the diameter of silicon carbide crystals based on laser-assisted heating as described in claim 7, characterized in that, The power modulation operation based on the average temperature of the crystal to obtain the updated power gradient includes: Adjacent power gradients are identified from the power gradient set based on the first-order power gradient. If the average temperature of the crystal is greater than the preset end temperature limit, then the power reduction operation is performed on the adjacent power gradients to obtain the first controlled power gradient. If the average temperature of the crystal is less than the preset lower limit of the end temperature, then the power gradient of the adjacent power gradient is increased to obtain the second controlled power gradient. If the average crystal temperature is not greater than the upper limit of the termination temperature and not less than the lower limit of the termination temperature, then the adjacent power gradients are taken as the optimal power gradients. The updated power gradient is determined based on the first controlled power gradient, the second controlled power gradient, or the optimal power gradient.

9. The method for expanding the diameter of silicon carbide crystals based on laser-assisted heating as described in claim 8, characterized in that, The formula for calculating the first controlled power gradient is as follows: ， in, This represents the first control power gradient. Indicates the adjacent power gradient, This represents the natural exponential function. Indicates the average temperature of the crystal. Indicates the upper limit of the end temperature. This indicates the preset thermal inertia compensation temperature.

10. A silicon carbide crystal diameter expansion system based on laser-assisted heating, characterized in that, The system includes: The control parameter setting module is used to identify the silicon carbide crystal, laser, main nozzle and auxiliary nozzle, fix the silicon carbide crystal to obtain a fixed silicon carbide crystal, and set the gas auxiliary parameters, including: target blowing angle, negative bias distance and argon flow rate. The nozzle angle control module is used to determine the processing start position based on the fixed silicon carbide crystal, construct a three-dimensional rectangular crystal coordinate system based on the processing start position, perform nozzle angle control operation based on the target blowing angle in the main jet nozzle and gas auxiliary parameters to obtain the adjusted main jet nozzle, perform gas flow field test and control on the fixed silicon carbide crystal based on the adjusted main jet nozzle to obtain the optimal nozzle angle, perform nozzle angle correction operation on the adjusted main jet nozzle using the optimal nozzle angle to obtain the optimal angle main jet nozzle, and adjust the offset distance of the optimal angle main jet nozzle based on the three-dimensional rectangular crystal coordinate system to obtain the calibrated main jet nozzle; The crystal diameter expansion control module is used to perform crystal diameter expansion control operations on a fixed silicon carbide crystal based on the calibration of the main jet nozzle, laser and auxiliary jet nozzle, to obtain a silicon carbide crystal with expanded diameter; The crystal diameter expansion control module is used to complete the diameter expansion of a silicon carbide crystal based on laser-assisted heating, using an already expanded silicon carbide crystal.

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