Method and system for determining flatness, electronic equipment and storage medium

Abstract

The invention provides a method and a system for determining the flatness of a graphite substrate, electronic equipment and a storage medium, the method comprises the following steps: obtaining performance parameters of the graphite substrate and spatial position distribution and constraint types of supporting points, a supporting structure providing support for the graphite substrate at the supporting points; based on the performance parameters, the spatial position distribution of the supporting points and the constraint type, constructing geometric models of the graphite matrix and the supporting structure; grid division is conducted on the geometric model, and grid encryption is conducted on the area, corresponding to the supporting points, of the graphite base body; determining boundary conditions of the geometric model, wherein the boundary conditions comprise a temperature field boundary condition and a stress field boundary condition; based on the boundary conditions, thermal-mechanical coupling simulation is conducted on the geometric model, deformation distribution data of the surface of the graphite matrix are obtained, and the deformation distribution data are used for representing the flatness of the graphite matrix. The technical scheme of the invention has relatively high calculation efficiency and simulation accuracy.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of simulation, in particular to a method and system for determining flatness of a graphite substrate, an electronic device and a storage medium. BACKGROUND

[0002] With the continuous development of economy, the scale of China's integrated circuit industry is growing, and the quality requirements for semiconductor epitaxial layers are becoming higher and higher. Epitaxy (EPI) is a process of depositing a new single crystal layer with required conductivity type, resistivity, thickness and crystal lattice structure integrity on a single crystal substrate along its original crystal axis direction by chemical vapor deposition. In the process of silicon carbide epitaxial growth, the flatness of the silicon carbide film layer directly affects the quality of the epitaxial layer, and a flat silicon carbide film layer surface can ensure uniform growth of the epitaxial material. Since the silicon carbide film layer is a uniform film layer formed on the surface of the graphite substrate by chemical vapor deposition, the flatness of the graphite substrate determines the flatness of the silicon carbide film layer. Therefore, it is crucial to ensure the flatness of the graphite substrate when preparing the silicon carbide film layer. SUMMARY

[0003] To solve the above problems, the present application provides a method and system for determining the flatness of a graphite substrate, an electronic device and a storage medium.

[0004] In a first aspect, the present application provides a method for determining the flatness of a graphite substrate, comprising: obtaining performance parameters of the graphite substrate, and spatial position distribution and constraint type of support points, wherein a support structure provides support for the graphite substrate at the support points; constructing a geometric model of the graphite substrate and the support structure based on the performance parameters, the spatial position distribution of the support points and the constraint type; performing mesh division on the geometric model, wherein the region of the graphite substrate corresponding to the support points is subjected to mesh encryption; determining the boundary conditions of the geometric model, the boundary conditions including temperature field boundary conditions and stress field boundary conditions; performing thermal-mechanical coupling simulation on the geometric model based on the boundary conditions to obtain deformation distribution data of the surface of the graphite substrate, the deformation distribution data being used to represent the flatness of the graphite substrate.

[0005] In combination with the first aspect, in some implementations, the mesh division of the geometric model comprises: performing first mesh size division on the region of the graphite substrate corresponding to the support points; performing second mesh size division on the region of the graphite substrate not corresponding to the support points; and performing third mesh size division on the support structure, wherein the first mesh size is smaller than the second mesh size, and the second mesh size is smaller than the third mesh size.

[0006] In some implementations, in combination with the first aspect, the first grid size is greater than or equal to 0.5 mm and less than or equal to 2 mm; and / or, the second grid size is greater than or equal to 1 mm and less than or equal to 3 mm; and / or, the third grid size is greater than or equal to 10 mm and less than or equal to 20 mm.

[0007] In some implementations, in combination with the first aspect, determining the boundary condition of the geometric model comprises: determining surface temperature distribution data of the graphite matrix under the actual working condition; and determining the surface temperature distribution data as the temperature field boundary condition.

[0008] In some implementations, in combination with the first aspect, determining the surface temperature distribution data of the graphite matrix under the actual working condition comprises: measuring the temperature of the surface of the graphite matrix at different positions under the actual working condition by using a temperature measuring device; and determining the surface temperature distribution data based on the temperature of the surface of the graphite matrix at different positions.

[0009] In some implementations, in combination with the first aspect, determining the boundary condition of the geometric model comprises: obtaining the rotating speed and the gravitational acceleration of the graphite matrix under the actual working condition, and the friction coefficient of the support point; and determining the rotating speed, the gravitational acceleration and the friction coefficient as the stress field boundary condition.

[0010] In some implementations, in combination with the first aspect, the performance parameters comprise at least one of a thermal expansion coefficient, a Poisson's ratio, an elastic modulus, and a density.

[0011] In the second aspect, the embodiments of the present application further provide a system for determining the flatness of a graphite matrix, comprising: an obtaining module, a constructing module, a dividing module, a determining module and a simulating module; wherein the obtaining module is configured to obtain performance parameters of the graphite matrix, and spatial position distribution and constraint type of support points, wherein a support structure provides support for the graphite matrix at the support points; the constructing module is configured to construct a geometric model of the graphite matrix and the support structure based on the performance parameters, the spatial position distribution of the support points and the constraint type; the dividing module is configured to divide the geometric model into grids, wherein the area of the graphite matrix corresponding to the support points is grid-encrypted; the determining module is configured to determine boundary conditions of the geometric model, the boundary conditions comprising temperature field boundary conditions and stress field boundary conditions; and the simulating module is configured to perform thermal-mechanical coupling simulation on the geometric model based on the boundary conditions, to obtain deformation distribution data of the surface of the graphite matrix, the deformation distribution data being used to represent the flatness of the graphite matrix.

[0012] In the third aspect, the embodiments of the present application further provide an electronic device, comprising: a processor; a memory connected with the processor, the memory being configured to store a computer program, the computer program being configured to implement the method for determining the flatness of a graphite matrix when executed by the processor.

[0013] In a fourth aspect, the embodiments of the present application further provide a storage medium, which has a computer program stored thereon, and the computer program, when executed by a processor, implements the method for determining the flatness of a graphite substrate.

[0014] In a fifth aspect, the embodiments of the present application provide a computer program product, which includes computer program instructions, and the computer program instructions, when executed by a processor, implement the method for determining the flatness of a graphite substrate.

[0015] According to the above technical solution, after the support mode of the support structure to the graphite substrate is determined, the temperature field and the stress field are coupled in combination with the actual working environment of the graphite substrate when the silicon carbide coating is deposited, the deformation of the graphite substrate under the working condition is simulated, the deformation distribution data of the surface of the graphite substrate is obtained through simulation calculation, the deformation distribution data can represent the flatness of the graphite substrate under the current support mode, and then the flatness of the graphite substrate can be further improved by adjusting the support mode, thereby facilitating the improvement of the flatness of the silicon carbide film layer. In the embodiments of the present application, only the key physical field influencing factors (temperature field and stress field) are captured to reduce the complexity of the simulation model, and the simulation accuracy is good while the calculation efficiency is improved. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 FIG. 1 is a flowchart of a method for determining the flatness of a graphite substrate according to an embodiment of the present application.

[0017] Figure 2 FIG. 2 is a structural block diagram of a system for determining the flatness of a graphite substrate according to an embodiment of the present application.

[0018] Figure 3 FIG. 3 is a structural diagram of an electronic device according to an embodiment of the present application. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of the present application.

[0020] At present, when preparing a silicon carbide film layer, a chemical vapor deposition method is usually used to form a uniform and dense silicon carbide coating on the surface of a graphite substrate. During the deposition process, it is very important to ensure that the planarity of the graphite substrate undergoes small and uniform deformation. In the case of uniform deposition, the planarity of the graphite substrate determines the planarity of the deposited silicon carbide film layer and is a key factor for ensuring high-quality epitaxial growth. It can not only directly affect the uniformity and crystal quality of the epitaxial layer, but also optimize the heat conduction performance, reduce mechanical damage and pollution. The planarity of the graphite substrate is affected by many factors, among which the support mode of the tooling plays an important role in the planarity of the graphite substrate. However, there is currently less research on how the tooling affects the planarity of the graphite substrate. The "planarity" refers to the deviation of the macroscopic concave-convex height of the substrate (for example, the graphite substrate) from the ideal plane. The planarity is an index for limiting the variation of the actual plane from its ideal plane and is used to control the shape error of the measured actual plane.

[0021] Based on this, the embodiment of the present application provides a method for determining the planarity of a graphite substrate. The method comprises: obtaining performance parameters of the graphite substrate, and spatial position distribution and constraint type of support points, wherein the support structure provides support for the graphite substrate at the support points; based on the performance parameters, the spatial position distribution of the support points and the constraint type, a geometric model of the graphite substrate and the support structure is constructed; the geometric model is meshed, wherein the area of the graphite substrate corresponding to the support points is meshed densely; the boundary conditions of the geometric model are determined, and the boundary conditions include temperature field boundary conditions and stress field boundary conditions; based on the boundary conditions, the geometric model is simulated by thermal-mechanical coupling to obtain deformation distribution data of the surface of the graphite substrate, and the deformation distribution data is used to represent the planarity of the graphite substrate. In the embodiment of the present application, after the support mode of the support structure to the graphite substrate is determined, the temperature field and the stress field are coupled in combination with the actual working environment of the graphite substrate during the deposition of the silicon carbide coating, the deformation of the graphite substrate under this working condition is simulated, the deformation distribution data of the surface of the graphite substrate is obtained by simulation calculation, the deformation distribution data can represent the planarity of the graphite substrate under the current support mode, and then the planarity of the graphite substrate can be further improved by adjusting the support mode, thereby facilitating the improvement of the planarity of the silicon carbide film layer. In the embodiment of the present application, only the key physical field influencing factors (temperature field and stress field) are captured to reduce the complexity of the simulation model, which improves the calculation efficiency while having good model accuracy and actual matching degree, and the simulation accuracy is high.

[0022] The following will be described in detail Figure 1 The technical scheme of the present application will be described in detail.

[0023] Figure 1 is a flowchart of the method for determining the planarity of the graphite substrate provided by an embodiment of the present application. As shown in Figure 1As shown, the method comprises the following steps.

[0024] In step S110, the performance parameters of the graphite matrix, the spatial position distribution of the support points, and the constraint types are obtained.

[0025] In some embodiments, the performance parameters include at least one of a coefficient of thermal expansion, a Poisson's ratio, an elastic modulus, and a density. The coefficient of thermal expansion is related to temperature, and the higher the temperature, the greater the coefficient of thermal expansion. Alternatively, the coefficient of thermal expansion here can be the coefficient of thermal expansion of the graphite matrix at the temperature of the actual working condition. Or the coefficient of thermal expansion is a coefficient of thermal expansion curve varying with temperature, so that when the geometric model is constructed, the corresponding coefficient of thermal expansion can be selected according to the temperature of the actual working condition. After the graphite matrix is determined, the Poisson's ratio, the elastic modulus, and the density are determined values, and these values can represent the mechanical properties of the graphite matrix. It can be understood that in some other embodiments, other performance parameters such as thermal conductivity can also be selected to more comprehensively reflect the physical characteristics of the graphite matrix in a thermal environment, which can be flexibly selected according to the simulation requirements.

[0026] Alternatively, the support structure provides support to the graphite matrix at the support points. That is, in the embodiments of the present application, the support structure supports the graphite matrix in a point support manner, for example, through three-point support, four-point support, five-point support, six-point support, etc.

[0027] The spatial position distribution of the support points refers to the specific coordinates of each point where the support structure contacts the graphite matrix in a three-dimensional coordinate system. For example, if the support structure adopts three-point support, the X-axis, Y-axis, and Z-axis coordinate values of the three support points on the bottom surface of the graphite matrix need to be determined, and the distribution manner directly affects the stability and stress of the graphite matrix in the supported state. The constraint type is used to limit the spatial freedom of the graphite matrix at the support points. Common constraint types include fixed constraint, hinged constraint, and sliding constraint, etc. The fixed constraint limits the translational freedom and rotational freedom of the support points in the X, Y, and Z directions. The hinged constraint usually limits the translational freedom of the support points in the X, Y, and Z directions, but allows a certain degree of rotation. The sliding constraint can only limit the translational or rotational freedom in some directions, for example, allowing sliding along a certain specific plane while limiting movement perpendicular to the plane. By determining the constraint type, the actual support effect of the support structure on the graphite matrix can be more accurately simulated. In the embodiments of the present application, the constraint type is a sliding constraint, that is, the support structure directly contacts the graphite matrix, and there is a friction force between the graphite matrix and the support structure.

[0028] In step S120, a geometric model of the graphite matrix and the support structure is constructed based on the performance parameters, the spatial position distribution of the support points, and the constraint types.

[0029] After obtaining the above data, a professional three-dimensional modeling software (for example, ANSYS, COMSOL Multiphysics, etc.) can be used to construct the geometric model. First, a three-dimensional model of the graphite matrix is created according to the actual size parameters (such as length, width, thickness, etc.) of the graphite matrix. The surface shape can be circular, square or other specific shape, which can be determined according to the actual situation. According to the spatial position distribution of the support points and the design form of the support structure (for example, support column, support block, etc.), a three-dimensional model of the support structure is constructed at the corresponding position, ensuring that the support structure and the graphite matrix are in accurate contact at the support points. In the modeling process, the performance parameters of the graphite matrix (such as thermal expansion coefficient, density, elastic modulus, Poisson's ratio, etc.) need to be assigned to the three-dimensional model of the graphite matrix. Since the support structure does not belong to the simulation object of the present application, the material properties of the support structure are directly set to default values and do not need to be adjusted. In addition, according to the constraint type, the support points are subjected to corresponding constraint conditions in the geometric model. For example, if the constraint type is sliding constraint, the support points are set to allow the graphite matrix to slide in a specific direction (for example, parallel to the surface of the graphite matrix) while limiting its movement in the vertical direction in the model, to simulate the relative motion relationship between the graphite matrix and the support structure under the actual support state. Through the above steps, the geometric model of the graphite matrix and the support structure is constructed.

[0030] In step S130, the geometric model is meshed.

[0031] Optionally, the area of the graphite matrix corresponding to the support points is meshed.

[0032] Illustratively, meshing is to discretize a continuous geometric model into a finite number of elements with determined shape and nodes for numerical calculation. In the embodiment of the present application, when meshing the geometric model, a non-uniform meshing strategy is adopted, and the region corresponding to the support points of the graphite substrate is focused on for mesh refinement. Specifically, this step can include: performing first mesh size division on the region corresponding to the support points of the graphite substrate; performing second mesh size division on the region not corresponding to the support points of the graphite substrate; and performing third mesh size division on the support structure. Wherein, the first mesh size is smaller than the second mesh size, and the second mesh size is smaller than the third mesh size. It should be noted that the region corresponding to the support points of the graphite substrate includes the region on the side of the graphite substrate in contact with the support structure and the region on the side of the graphite substrate not in contact with the support structure. Since the support point region is a region with large stress concentration and deformation gradient, using a smaller first mesh size can more accurately capture the stress change in this region and improve the accuracy of the simulation results; the region not corresponding to the support points of the graphite substrate is relatively flat in terms of stress change, so using a slightly larger second mesh size can reduce the number of elements and improve the calculation efficiency while ensuring calculation accuracy; the support structure mainly serves as a support, and its own deformation has relatively small influence on the flatness of the graphite substrate, so a larger third mesh size can be used for division.

[0033] In some embodiments, the first mesh size is greater than or equal to 0.5 mm and less than or equal to 2 mm, for example, it can be 0.5 mm, 1 mm, 1.5 mm, 2 mm, etc. By limiting the first mesh size within this range, the demand for high-precision calculation of the support point region can be met, and the problem of excessive number of elements and excessive consumption of computing resources caused by too small mesh size can be avoided. The second mesh size is greater than or equal to 1 mm and less than or equal to 3 mm, for example, it can be 1 mm, 2 mm, 2.5 mm, 3 mm, etc. The selection of this size range takes into account the balance between the calculation accuracy and the calculation efficiency of the non-support point region of the graphite substrate. The third mesh size is greater than or equal to 10 mm and less than or equal to 20 mm, for example, it can be 10 mm, 15 mm, 18 mm, 20 mm, etc. While ensuring the basic characteristics of the support structure model, the calculation is simplified to the greatest extent. It should be noted that the specific values of the above mesh sizes are only examples, and in actual application, they can be adjusted appropriately according to the size of the graphite substrate, the number and distribution density of the support points, the requirement for simulation accuracy, and the computing power of the computer hardware, etc.

[0034] In step S140, the boundary conditions of the geometric model are determined.

[0035] Optionally, the boundary conditions include temperature field boundary conditions and stress field boundary conditions.

[0036] In some embodiments, the temperature field boundary condition is used to simulate the temperature distribution of the graphite substrate in actual working conditions. The temperature field boundary condition refers to the temperature distribution of the surface of the graphite substrate after reaching the working temperature (e.g., the temperature for chemical vapor deposition). In the process of silicon carbide epitaxial growth, the graphite substrate usually needs to be heated to a high temperature, for example, 1500-2000°C, and there can be temperature differences at different positions of the graphite substrate. Therefore, the temperature data in actual working conditions can be obtained by experimental measurement. Illustratively, the step of determining the temperature field boundary condition includes: determining the surface temperature distribution data of the graphite substrate in actual working conditions; and determining the surface temperature distribution data as the temperature field boundary condition. The temperature field boundary condition thus determined can reflect the actual working conditions, thereby improving the simulation accuracy. Optionally, the surface temperature distribution data of the graphite substrate in actual working conditions is determined by: in actual working conditions, measuring the temperatures of the surface of the graphite substrate at different positions by using a temperature measuring device; and determining the surface temperature distribution data based on the temperatures of the surface of the graphite substrate at different positions. In the embodiments of the present application, the temperature measuring device can include a temperature measuring ring. Illustratively, if the surface of the graphite substrate is annular, the graphite substrate is divided into three layers, i.e., an inner layer, a middle layer, and an outer layer, three temperature data are measured by using the temperature measuring ring, and the temperature data of the unmeasured region are determined by interpolation, so as to obtain the temperature distribution data of the surface of the graphite substrate.

[0037] In some embodiments, the temperature field boundary condition can also be determined based on theoretical calculation or empirical formula. For example, the surface temperature distribution of the graphite substrate is calculated by a heat conduction equation according to the power of the heating device, the thermal conductivity of the graphite substrate, the environmental heat dissipation coefficient, and other parameters. Alternatively, the temperature distribution data under similar process conditions are referred to, and the temperature field boundary condition is obtained by modification in combination with the specific working conditions of the present application.

[0038] The stress field boundary condition is used to simulate the external stress received by the graphite substrate in actual working conditions. In the process of silicon carbide deposition, the graphite substrate and the support structure need to be rotated in the chamber to ensure uniform deposition. The external load received by the graphite substrate includes the support force provided by the support structure, the gravity of the graphite substrate itself, and the friction force between the graphite substrate and the support structure during rotation. Optionally, the determination of the stress boundary condition includes: obtaining the rotation speed and the gravitational acceleration of the graphite substrate in actual working conditions, and the friction coefficient of the support point; and determining the rotation speed, the gravitational acceleration, and the friction coefficient as the stress field boundary condition. Optionally, in actual working conditions, the rotation speed of the graphite substrate is 1.5 r / min, the gravitational acceleration is 9.8 m / s 2, the friction coefficient is 0.2 (the coefficient is an empirical coefficient in engineering applications). The direction of the gravity passing through the graphite matrix is vertically downward, and the size is the product of the mass of the graphite matrix and the gravity acceleration. The mass of the graphite matrix can be determined by the density and the volume of the graphite matrix. Since the graphite matrix and the support structure rotate, there is a sliding friction between the graphite matrix and the support structure. According to the friction coefficient and the mass of the graphite matrix, the friction can be determined. The support force provided by the support structure to the graphite matrix at each support point is balanced with the component of the gravity and the friction in the vertical support surface direction, so as to ensure the force balance of the graphite matrix at the support point. By taking the rotation speed, the gravity acceleration and the friction coefficient as the stress field boundary conditions, the centrifugal force, the gravity and the friction and other external stresses borne by the graphite matrix during rotation can be accurately simulated, and accurate mechanical input is provided for subsequent thermal-mechanical coupling simulation.

[0039] In step S150, the thermal-mechanical coupling simulation is performed on the geometric model based on the boundary conditions to obtain the deformation distribution data of the surface of the graphite matrix.

[0040] Optionally, the thermal-mechanical coupling simulation can adopt a sequential coupling or a direct coupling method. The sequential coupling includes first performing temperature field simulation to obtain the temperature distribution results of each node of the geometric model, then applying the temperature distribution results as body load to the stress field simulation, and performing structural mechanics analysis to obtain the deformation distribution data. The direct coupling simultaneously solves the temperature field control equation and the stress field control equation in the same solver, and considers the mutual influence between temperature and stress. For example, thermal stress caused by temperature change will lead to material deformation, and the deformation may affect the heat conduction path and thus change the temperature distribution. In the embodiments of the present application, considering that the thermal expansion and thermal stress of the graphite matrix in a high-temperature environment are the main factors leading to its deformation, and the temperature has a significant influence on the material performance parameters (for example, the thermal expansion coefficient), the direct thermal-mechanical coupling simulation method is preferably adopted to more accurately simulate the actual physical deformation process.

[0041] Optionally, the graphite matrix expands thermally at high temperature, thereby generating deformation. For linear materials, the length change can be calculated by formula (1).

[0042] (1) wherein, is the length change, is the thermal expansion coefficient of the material; is the initial length; is the temperature change.

[0043] In the thermal-mechanical coupling simulation, the temperature field boundary conditions and stress field boundary conditions determined in the above steps are applied to the geometric model after meshing, and the control equation is solved by a finite element analysis software (such as ANSYS, ABAQUS, COMSOL Multiphysics, etc.). The displacement data of each point on the surface of the graphite matrix is extracted, and the deformation distribution data is determined based on the displacement data.

[0044] Exemplarily, the control equation is determined by formula (2).

[0045] (2) [K] is the total stiffness matrix, representing the ability of the structure to resist deformation; {D} is the node displacement vector, representing the node displacement of the structure under the action of the load; {F} is the node force vector, representing the external force acting on the structure.

[0046] Optionally, the deformation distribution data is used to represent the flatness of the graphite matrix. The deformation distribution data can be the displacement components (such as displacement along the X-axis, Y-axis, and Z-axis) of each node on the surface of the graphite matrix in three-dimensional space. By analyzing these displacement components, especially the displacement component perpendicular to the surface of the graphite matrix (i.e., the deformation in the flatness direction), the flatness of the graphite matrix can be intuitively reflected. For example, if the Z-axis direction displacement of a certain region on the surface of the graphite matrix is large, it indicates that the flatness of this region is poor; on the contrary, if the Z-axis direction displacement is small and uniformly distributed, it indicates that the flatness of the graphite matrix is good. The deformation distribution data obtained by thermal-mechanical coupling simulation can provide quantitative basis for evaluating the flatness of the graphite matrix under the current support mode, and then the spatial position distribution of the support points, the constraint type or the design parameters of the support structure can be adjusted accordingly, and the simulation calculation is performed again until the flatness that meets the requirements is obtained.

[0047] In some embodiments, after obtaining the deformation distribution data, the method further comprises: determining the flatness error value of the graphite matrix based on the deformation distribution data. If the flatness error value is greater than a preset threshold, the spatial position distribution of the support points is adjusted, and steps S110 to S150 are returned to be executed until the flatness error value is less than or equal to the preset threshold. The preset threshold can be set according to the flatness requirement of the silicon carbide film layer and the acceptable range of the actual production process. Through this iterative optimization method, the spatial position distribution of the support points that optimizes the flatness of the graphite matrix can be found, thereby providing a theoretical basis for the design and optimization of the tooling support structure.

[0048] For example, the initial setting adopts three-point support, the support points are uniformly distributed on the circumference of the bottom surface of the graphite substrate, and the constraint type is sliding constraint. Through the thermal-mechanical coupling simulation, the flatness error value is 50 μm, which is greater than the preset threshold value 30 μm. At this time, the number of support points can be adjusted, such as increasing to four-point support; or the contact area of the support structure at the support point and the graphite substrate is adjusted. Then the above steps are re-executed, the flatness error value under the new support mode is calculated, and if it still does not meet the requirements, the adjustment is continued until the flatness error value meets the preset threshold value.

[0049] The deformation obtained by the simulation in the embodiment of the present application is similar to the deformation range obtained by the multi-physical coupling simulation in the prior art, that is, the simulation result in the embodiment of the present application also has high accuracy, and the one-way coupling model of the temperature field and the stress field in the embodiment of the present application is simpler, the calculation time is faster, and the efficiency is higher. Therefore, the technical scheme of the present application can balance the calculation efficiency and the simulation accuracy.

[0050] In the embodiment of the present application, after the support mode of the support structure to the graphite substrate is determined, the temperature field and the stress field are coupled in combination with the actual working environment of the graphite substrate during the deposition of the silicon carbide coating, the deformation of the graphite substrate under the working condition is simulated, the deformation distribution data of the surface of the graphite substrate is obtained by simulation calculation, the flatness of the graphite substrate under different support modes is accurately predicted, and therefore the flatness of the graphite substrate can be improved by adjusting the support mode, thereby facilitating the improvement of the deposition quality of the silicon carbide film layer, having important application value for the semiconductor epitaxial growth. In the embodiment of the present application, only the key physical field influencing factors (temperature field and stress field) are captured to reduce the complexity of the simulation model, the calculation efficiency is improved, and the model accuracy and actual matching degree are good, and the simulation accuracy is high.

[0051] It should be understood that the size of the serial number of each step in the above embodiment does not mean the order of execution, and the execution order of each process should be determined according to its function and internal logic, and should not constitute any limitation on the implementation process of the embodiment of the present application. For example, in some embodiments, steps S110 to S150 are executed in logical order, but in some cases, step S140 can be performed before or in parallel with part of the operation of step S130, as long as the determination of the boundary condition and the mesh division are completed before the simulation is performed.

[0052] Figure 2 The system for determining the flatness of a graphite substrate provided in an embodiment of the present application. As shown in Figure 2 The system 200 includes an acquisition module 210, a construction module 220, a division module 230, a determination module 240, and a simulation module 250.

[0053] Optionally, the obtaining module 210 is configured to obtain a performance parameter of the graphite base, and a spatial position distribution and a constraint type of the support points at which the support structure supports the graphite base.

[0054] The constructing module 220 is configured to construct a geometric model of the graphite base and the support structure based on the performance parameter, the spatial position distribution of the support points, and the constraint type.

[0055] The dividing module 230 is configured to perform mesh division on the geometric model, and the graphite base is mesh-encrypted in the region corresponding to the support points.

[0056] The determining module 240 is configured to determine a boundary condition of the geometric model, and the boundary condition includes a temperature field boundary condition and a stress field boundary condition.

[0057] The simulation module 250 is configured to perform thermal-mechanical coupling simulation on the geometric model based on the boundary condition, and obtain deformation distribution data of a surface of the graphite base, the deformation distribution data being used to represent flatness of the graphite base.

[0058] The specific working principle and benefits of the system for determining the flatness of the graphite base provided in the embodiments of the present application are similar to those of the method for determining the flatness of the graphite base provided in the embodiments of the present application, and will not be repeated here.

[0059] Figure 3 FIG. 1 is a structural schematic diagram of an electronic device according to an embodiment of the present application.

[0060] As shown in FIG. 1, the electronic device 300 includes one or more processors 301 and a memory 302. Figure 3 The processor 301 can be a central processing unit (CPU) or other forms of processing units having data processing capability and / or instruction execution capability, and can control other components in the electronic device 300 to perform desired functions.

[0061]

[0062] ​The memory 302 can include one or more computer program products that can include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory, for example, can include random access memory (RAM), and / or a cache, etc. The non-volatile memory, for example, can include read-only memory (ROM), hard disk, flash memory, etc. One or more computer program instructions can be stored on the computer-readable storage media, and the processor 301 can execute the program instructions to implement the method of determining flatness of a graphite substrate and / or other desired functions of various embodiments of the present application described above. Various contents such as performance parameters of the graphite substrate, geometric models, etc. can also be stored in the computer-readable storage media.

[0063] In one example, the electronic device 300 can further include an input device 303 and an output device 304, which are interconnected through a bus system and / or other forms of connection mechanisms (not shown).

[0064] The input device 303 can include, for example, a keyboard, a mouse, etc.

[0065] The output device 304 can output various information to the outside, including the deformation distribution data of the surface of the graphite substrate, etc. The output device 304 can include, for example, a display, a speaker, a printer, a communication network and a remote output device connected thereto, etc.

[0066] Of course, in order to simplify, Figure 3 Only some of the components in the electronic device 300 related to the present application are shown in the figure, and components such as buses, input / output interfaces, etc. are omitted. In addition, the electronic device 300 can also include any other appropriate components according to specific application cases.

[0067] In addition to the above method and device, the embodiments of the present application can also be a computer program product including computer program instructions, which, when executed by a processor, cause the processor to perform the steps in the method of determining flatness of a graphite substrate according to various embodiments of the present application described above in the specification.

[0068] The computer program product can be written in any combination of one or more programming languages, including an object oriented programming language such as Java, C++ or the like, and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The program code can execute entirely on the user's computing device, partly on the user's computing device, as a stand-alone software package, partly on the user's computing device and partly on a remote computing device or entirely on the remote computing device or server. The embodiments of the present application are not limited by the programming languages used to implement the routines.

[0069] In addition, an embodiment of the present application can also be a computer readable storage medium, which stores computer program instructions, and when the computer program instructions are run by a processor, the processor executes the steps of the method for determining flatness of a graphite substrate according to various embodiments of the present application described above in the specification.

[0070] The computer readable storage medium can take any combination of one or more of the following: a readable signal medium or a readable storage medium. The readable storage medium can include, but is not limited to, an electrical, a magnetic, an optical, an electromagnetic, an infrared, or a semiconductor system, device or apparatus, or any combination of the above. More specific examples (a non-exhaustive list) of the readable storage medium include an electrical connection having one or more wires, a portable disc, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above.

[0071] The above describes the basic principles of the present application in combination with specific embodiments, but it should be noted that the advantages, advantages, effects and the like mentioned in the present application are only examples and are not limiting, and these advantages, advantages, effects and the like cannot be considered as the must-have of each embodiment of the present application. In addition, the above specific details are only for the purpose of example and understanding, and are not limiting, and the above details do not limit the present application to the must-use specific details.

[0072] The block diagrams of the devices, apparatuses, equipment, systems referred to in this application are only as illustrative examples and are not intended to require or imply that the connection, arrangement, configuration must be as shown in the block diagrams. These devices, apparatuses, equipment, systems can be connected, arranged, configured in any way as will be appreciated by those skilled in the art. Words such as "include", "contain", "have" and the like are open-ended words, mean "including but not limited to", and can be used interchangeably with each other. The words "or" and "and" used herein mean the word "and / or", and can be used interchangeably with each other, unless the context clearly indicates otherwise. The word "such as" used herein means the phrase "such as but not limited to", and can be used interchangeably with each other.

[0073] It should also be noted that in the devices, apparatuses and methods of the present application, each component or step can be decomposed and / or recombined. These decompositions and / or recombinations should be considered as equivalents of the present application.

[0074] The above description of disclosed aspects is provided to enable any person skilled in the art to make or use the application. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein can be applied to other aspects without departing from the scope of the application. Thus, the present application is not intended to be limited to the aspects shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0075] The above description has been given for the purpose of illustration and description. Furthermore, this description does not intend to limit the embodiments of the present application to the forms disclosed herein. Although a number of example aspects and embodiments have been discussed above, those skilled in the art will recognize certain modifications, permutations, additions, and sub-combinations thereof.

[0076] The above detailed description does not limit the scope of the application. Various modifications, combinations, sub-combinations and alternatives can occur to those skilled in the art without departing from the spirit and scope of the application. Any modification, equivalent replacement and improvement, etc. made within the spirit and principle of the application shall fall within the scope of the application.

Claims

1. A method for determining the flatness of a graphite matrix, characterized in that, include: The performance parameters of the graphite matrix, as well as the spatial distribution and constraint type of the support points, are obtained, wherein the support structure provides support to the graphite matrix at the support points; Based on the performance parameters, the spatial distribution of the support points, and the constraint type, a geometric model of the graphite matrix and the support structure is constructed. The geometric model is meshed, wherein the region of the graphite matrix corresponding to the support point is meshed more finely; Determine the boundary conditions of the geometric model, including temperature field boundary conditions and stress field boundary conditions; Based on the boundary conditions, a thermo-mechanical coupling simulation is performed on the geometric model to obtain deformation distribution data of the graphite matrix surface. The deformation distribution data is used to characterize the flatness of the graphite matrix.

2. The method for determining the flatness of a graphite matrix according to claim 1, characterized in that, The meshing of the geometric model includes: The region of the graphite matrix corresponding to the support point is divided into a first grid size; The region of the graphite matrix that does not correspond to the support point is divided into a second grid size; The support structure is divided into a third grid size, wherein the first grid size is smaller than the second grid size, and the second grid size is smaller than the third grid size.

3. The method for determining the flatness of a graphite matrix according to claim 2, characterized in that, The first grid size is greater than or equal to 0.5 mm and less than or equal to 2 mm; and / or, the second grid size is greater than or equal to 1 mm and less than or equal to 3 mm; and / or, the third grid size is greater than or equal to 10 mm and less than or equal to 20 mm.

4. The method for determining the flatness of a graphite matrix according to claim 1, characterized in that, Determining the boundary conditions of the geometric model includes: Determine the surface temperature distribution data of the graphite matrix under actual working conditions; The surface temperature distribution data is used as the boundary condition for the temperature field.

5. The method for determining the flatness of a graphite matrix according to claim 4, characterized in that, The determination of the surface temperature distribution data of the graphite matrix under actual working conditions includes: Under the actual working conditions, the temperature of the graphite matrix surface at different locations is measured using a temperature measuring device; The surface temperature distribution data is determined based on the temperature at different locations on the surface of the graphite matrix.

6. The method for determining the flatness of a graphite matrix according to claim 1, characterized in that, Determining the boundary conditions of the geometric model includes: Obtain the rotational speed and gravitational acceleration of the graphite matrix under actual working conditions, as well as the friction coefficient of the support point; determine the rotational speed, gravitational acceleration, and friction coefficient as the stress field boundary conditions.

7. The method for determining the flatness of a graphite matrix according to claim 1, characterized in that, The performance parameters include at least one of the following: coefficient of thermal expansion, Poisson's ratio, elastic modulus, and density.

8. A system for determining the flatness of a graphite matrix, characterized in that, include: The acquisition module is used to acquire the performance parameters of the graphite matrix, as well as the spatial distribution and constraint type of the support points, wherein the support structure provides support to the graphite matrix at the support points; A construction module is used to construct a geometric model of the graphite matrix and the support structure based on the performance parameters, the spatial distribution of the support points, and the constraint type. A meshing module is used to mesh the geometric model, wherein the region of the graphite matrix corresponding to the support point is meshed more finely; A determination module is used to determine the boundary conditions of the geometric model, the boundary conditions including temperature field boundary conditions and stress field boundary conditions; The simulation module is used to perform thermo-mechanical coupling simulation on the geometric model based on the boundary conditions to obtain deformation distribution data on the surface of the graphite matrix. The deformation distribution data is used to characterize the flatness of the graphite matrix.

9. An electronic device, characterized in that, include: processor; A memory connected to the processor, the memory being used to store a computer program that, when executed by the processor, implements the method for determining the flatness of a graphite matrix as described in any one of claims 1 to 7.

10. A storage medium, characterized in that, The storage medium stores a computer program, which, when executed by a processor, implements the method for determining the flatness of a graphite matrix as described in any one of claims 1 to 7.

Images