Shouldering control method, device and equipment based on pulling speed and storage medium

Abstract

The invention provides a pulling speed-based shouldering control method, which comprises the following steps of: for a selected crystal specification, selecting a corresponding pre-configured diameter growth rate prediction model and a pulling speed prediction model; in the shouldering stage, when the crystal grows to a preset length according to SOP control, predicting through a diameter growth rate prediction model to obtain a corresponding diameter growth rate prediction value when the length of the crystal is the sum of the preset length and one unit length; calculating through a pulling speed prediction model to obtain a corresponding pulling speed prediction value when the length of the crystal is a preset length plus a unit length; and controlling the pulling speed when the crystal length is equal to the sum of the preset length and one unit length based on the pulling speed predicted value. According to the method, the pulling speed can be dynamically adjusted in real time when the production environment changes, the survival rate of the crystal bar in the shouldering stage can be increased, and the consistency of the shoulder shape is better.

Description

Technical Field

[0001] This invention relates to the field of Czochralski method for producing single-crystal silicon rods, and in particular to a method, apparatus, equipment and storage medium for controlling the shoulder formation based on pulling speed. Background Technology

[0002] In the photovoltaic industry, the Czochralski method is the mainstream technology for preparing monocrystalline silicon ingots, and its quality directly affects the conversion efficiency of solar cells. The Czochralski method first involves placing polycrystalline silicon raw materials in a quartz crucible and melting them at high temperatures. The crystal pulling process includes key stages such as seed crystal formation, shoulder formation, constant-diameter growth, and finishing. Among these, the shoulder formation stage is particularly crucial, aiming to gradually grow a crystal ingot shoulder with a specific target diameter and a perfect monocrystalline structure from a small seed crystal. The success of shoulder formation directly determines the stability of subsequent constant-diameter growth, the overall quality of the ingot, and the final yield of silicon wafers.

[0003] Currently, conventional shoulder-growing processes mainly rely on preset, static combinations of process parameters (such as drawing speed, crucible lifting speed, heating power, etc.) for control, i.e., control according to SOP (Standard Operating Procedure). Two control methods have emerged: diameter-rate shoulder growing and shoulder-angle shoulder growing. Both methods essentially rely on a pre-set, desired shoulder growth path model to generate control commands (including parameters such as drawing speed, diameter growth rate, crucible lifting speed, main heater power, etc.).

[0004] However, the actual production environment is complex and variable, and there are unavoidable fluctuations in the thermal field (such as aging of heating elements, changes in cooling water temperature, disturbances in the argon gas flow field, and differences in the melt state of the raw materials). These disturbances can significantly affect the solid-liquid interface shape, temperature gradient, and thermal stress distribution during crystal growth. Under static parameter control, when faced with these disturbances, the shoulder-forming process controlled according to SOP (Standard Operating Procedure) is prone to problems such as shoulder angle deviation from the target, excessive diameter fluctuations, and even dislocations or shoulder formation failure. Summary of the Invention

[0005] To address at least one technical problem in the prior art, embodiments of the present invention provide a method, apparatus, device, and storage medium for shoulder formation control based on pulling speed; this allows for real-time dynamic adjustment of the pulling speed when the production environment changes, improving the survival rate of the crystal ingot during the shoulder formation stage and resulting in better consistency of the shoulder shape. To achieve the above technical objectives, the technical solution adopted by embodiments of the present invention is as follows:

[0006] In a first aspect, embodiments of the present invention provide a shoulder formation control method based on pulling speed, the method being used to control the shoulder formation process of a crystal during the shoulder formation stage of the Czochralski method, the method comprising:

[0007] For the selected crystal size, select the corresponding pre-configured diameter growth rate prediction model and pulling speed prediction model;

[0008] During the shoulder-forming stage, when the crystal grows to a preset length according to the standard operating procedure (SOP), the pulling speed, diameter growth rate, crucible lifting speed, and main power reduction for each unit length of crystal growth within the preset length interval before the preset length are obtained, wherein the preset length interval is less than or equal to the preset length; then, these are used as input data for the diameter growth rate prediction model, and the diameter growth rate prediction value corresponding to the crystal length being the preset length + one unit length is predicted by the diameter growth rate prediction model.

[0009] During the shoulder-forming stage, when the crystal grows to a preset length according to the standard operating procedure (SOP), the pulling speed and diameter growth rate corresponding to the preset crystal length are obtained. The pulling speed, diameter growth rate, and predicted diameter growth rate corresponding to the preset crystal length plus one unit length are used as input data for the pulling speed prediction model. The pulling speed prediction model is then used to calculate the predicted pulling speed corresponding to the preset crystal length plus one unit length.

[0010] The pulling speed is controlled based on the predicted pulling speed value when the crystal length is a preset length plus one unit length.

[0011] Furthermore, the preset length is 10 mm to 20 mm.

[0012] Furthermore, the preset length range is 10 mm to 20 mm.

[0013] Furthermore, the unit length is 1 mm to 2 mm.

[0014] Furthermore, the diameter growth rate prediction model is obtained through a first model training method, which includes the following steps:

[0015] For a selected crystal specification, production data of multiple crystals during the shoulder-forming stage is obtained, including: when the crystal grows to a preset length according to the standard operating procedure (SOP), the pulling speed, diameter growth rate, crucible lifting speed, and main power reduction of the crystal per unit length growth within the preset length interval before the preset length are obtained as input data for the diameter growth rate prediction model; wherein the preset length interval is less than or equal to the preset length; when the crystal grows to a preset length + one unit length according to the standard operating procedure (SOP), the diameter growth rate corresponding to the crystal length being the preset length + one unit length is obtained as output data for the diameter growth rate prediction model;

[0016] The diameter growth rate prediction model uses a Long Short-Time Memory (LSTM) network.

[0017] The diameter growth rate prediction model is trained based on the input and output data of the diameter growth rate prediction model; the diameter growth rate prediction model is used to predict the diameter growth rate when the crystal length is a preset length + one unit length.

[0018] Furthermore, the pulling speed prediction model is obtained through a second model training method, which includes the following steps:

[0019] For the selected crystal specification, obtain production data of multiple crystals during the shoulder-forming stage, including: when the crystal grows to a preset length + one unit length according to the standard operating procedure (SOP), obtain the pulling speed and the pulling speed difference when the crystal length is the preset length + one unit length; obtain the diameter growth rate and the diameter growth rate when the crystal length is the preset length + one unit length, and calculate the diameter growth rate difference.

[0020] The relationship between the difference in stretching speed and the difference in diameter growth rate was fitted to obtain the relationship expression;

[0021] The parameters in the relational expression are solved using the least squares method to establish a pulling speed prediction model; the pulling speed prediction model is used to calculate the pulling speed prediction value corresponding to a crystal length of a preset length plus one unit length.

[0022] Furthermore, the relational expression is shown in formula (4):

[0023] S l (L+1)-S l (L)=a*[S d (L+1)-S d (L)]+b (4)

[0024] Among them, S l (L+1) represents the pulling speed when the crystal length is the preset length plus one unit length, S l (L) represents the pulling speed corresponding to the crystal length being the preset length;

[0025] Among them, S d (L+1) represents the diameter growth rate when the crystal length is a preset length plus one unit length, S d (L) represents the diameter growth rate when the crystal length is the preset length;

[0026] The relational expression includes parameters a and b; a is the weight coefficient, and b is the bias term;

[0027] The speed prediction model is shown in formula (5):

[0028]

[0029] Among them, S l (L) represents the pulling speed corresponding to the crystal length being the preset length. This represents the predicted pulling speed when the crystal length is a preset length plus one unit length.

[0030] Secondly, embodiments of the present invention provide a shoulder release control device based on pulling speed, comprising:

[0031] The selection module is used to select the corresponding pre-configured diameter growth rate prediction model and pulling speed prediction model for the selected crystal size.

[0032] The diameter growth rate prediction module is used during the shoulder-forming stage to obtain, when the crystal grows to a preset length according to the standard operating procedure (SOP), the pulling speed, diameter growth rate, crucible lifting speed, and main power reduction corresponding to each unit length of crystal growth within a preset length interval before the preset length, wherein the preset length interval is less than or equal to the preset length; then, it is used as input data for the diameter growth rate prediction model, which predicts the diameter growth rate when the crystal length is the preset length + one unit length.

[0033] The pulling speed prediction module is used during the shoulder-forming stage to obtain the pulling speed and diameter growth rate corresponding to the crystal length when it grows to a preset length according to the standard operating procedure (SOP). The predicted values ​​of the pulling speed, diameter growth rate, and diameter growth rate when the crystal length is the preset length plus one unit length are used as input data to the pulling speed prediction model. The pulling speed prediction model then calculates the predicted pulling speed value when the crystal length is the preset length plus one unit length.

[0034] The pulling speed control module controls the pulling speed when the crystal length is a preset length plus one unit length, based on the predicted pulling speed value.

[0035] Thirdly, embodiments of the present invention provide an electronic device, including:

[0036] Memory, which stores computer programs;

[0037] A processor is configured to run the computer program, which, when running, performs the steps of the shoulder release control method based on pulling speed as described above.

[0038] Fourthly, embodiments of the present invention provide a storage medium storing a computer program configured to execute the steps of the shoulder release control method based on pulling speed as described above.

[0039] The beneficial effects of the technical solution provided by the embodiments of the present invention are as follows:

[0040] 1) Compared with the method of directly using SOP to control growth, this application adopts a diameter growth rate prediction model to predict the diameter growth rate, which fully considers the trend of production data such as pulling speed, crucible lifting speed and main power reduction, as well as the mutual influence between them and the diameter growth rate; thus making the short-term prediction of diameter growth rate more accurate when the thermal field fluctuates.

[0041] 2) This application calculates the predicted pulling speed for the next unit length using a pulling speed prediction model. When there are short-term fluctuations in the thermal field, it can avoid the pulling speed being too high or too low for a short time due to adjustment using only SOP. This allows the pulling speed to respond quickly and accurately to changes in the crystal growth state, reducing the probability of wire breakage caused by excessively high or low pulling speed, and improving the survival rate of the crystal rod during the shoulder formation stage. Attached Figure Description

[0042] Figure 1 This is a flowchart of the shoulder-releasing control method in an embodiment of the present invention.

[0043] Figure 2 This is a schematic diagram of the shoulder-relaxation control device in an embodiment of the present invention.

[0044] Figure 3 This is a schematic diagram of an electronic device in an embodiment of the present invention. Detailed Implementation

[0045] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0046] In the description of the embodiments of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0047] In the description of the embodiments of the present invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can also refer to the internal connection of two components; and they can refer to a wireless connection or a wired connection. Those skilled in the art can understand the specific meaning of the above terms in the present invention based on the specific circumstances.

[0048] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0049] In the embodiments of the present invention, for the sake of simplicity and convenience, crystal refers to a single-crystal silicon ingot produced by the Czochralski method; pulling speed refers to the upward pulling speed of the single-crystal silicon ingot.

[0050] This invention proposes a shoulder formation control method based on pulling speed. This method is used to control the shoulder formation process of crystals during the Czochralski pulling method, such as... Figure 1 As shown, it includes:

[0051] Step S110: For the selected crystal specification, select the corresponding pre-configured diameter growth rate prediction model and pulling speed prediction model.

[0052] Step S120: During the shoulder-forming stage, when the crystal grows to the preset length according to the standard operating procedure (SOP), the pulling speed, diameter growth rate, crucible lifting speed, and main power reduction of the crystal per unit length within the preset length interval before the preset length are obtained, wherein the preset length interval is less than or equal to the preset length; then, as input data for the diameter growth rate prediction model, the diameter growth rate prediction value corresponding to the crystal length being the preset length + one unit length is obtained through the diameter growth rate prediction model.

[0053] Compared with the method of directly using SOP to control growth, this application uses a diameter growth rate prediction model to predict the diameter growth rate, which fully considers the trend of production data such as pulling speed, crucible lifting speed and main feed power reduction, as well as the interaction between them and the diameter growth rate; thus, the short-term prediction of the diameter growth rate under thermal fluctuations is more accurate.

[0054] Step S130: During the shoulder-forming stage, when the crystal grows to a preset length according to the standard operating procedure (SOP), the pulling speed and diameter growth rate corresponding to the preset crystal length are obtained. The pulling speed, diameter growth rate, and diameter growth rate predictions corresponding to the preset crystal length plus one unit length are used as input data for the pulling speed prediction model. The pulling speed prediction model is then used to calculate the pulling speed prediction value corresponding to the preset crystal length plus one unit length.

[0055] This application calculates the predicted pulling speed for the next unit length using a pulling speed prediction model, which avoids the pulling speed being too high or too low in the short term due to adjustment using only SOP. This allows the pulling speed to respond quickly and accurately to changes in the crystal growth state, reducing the probability of wire breakage caused by excessively high or low pulling speeds, and improving the survival rate of the crystal rod during the shoulder formation stage.

[0056] Step S140: Based on the predicted pulling speed value, control the pulling speed when the crystal length is a preset length plus one unit length.

[0057] In the Czochralski process, the crystal length is typically 140 mm to 180 mm at the end of the shoulder formation stage. Therefore, in a specific embodiment, the preset length is 10 mm to 20 mm. This way, after the shoulder formation stage is controlled according to the SOP (Standard Operating Procedure), the pulling speed can be adjusted in real time according to changes in the production environment within a short period of time.

[0058] The preset length range is usually equal to or less than the preset length, for example, the preset length range is 10 mm to 20 mm. When the crystal grows to the preset length according to the SOP, the pulling speed, diameter growth rate, crucible lifting speed and main power reduction of the crystal per unit length of growth within the preset length range before the preset length are obtained. Then, the diameter growth rate prediction value can be obtained by using the diameter growth rate prediction model.

[0059] The unit length needs to be compatible with the preset length and preset length range, so the unit length is 1 mm to 2 mm. The unit length is often an integer, such as 1 mm or 2 mm.

[0060] The pulling speed corresponding to each unit length of crystal growth is obtained by dividing each unit length of crystal growth by the corresponding time interval.

[0061] The diameter growth rate per unit length of crystal growth is obtained by dividing the diameter growth length per unit length of crystal growth by the corresponding time interval.

[0062] In some embodiments, the crystal length and crystal diameter can be obtained by a real-time measurement method based on image processing, thereby obtaining the crystal growth length per unit length and the diameter growth length corresponding to the crystal growth length per unit length.

[0063] Let the preset length be L, where "1" represents one unit length.

[0064] The pulling speed corresponding to the crystal length when the crystal length is the preset length can be obtained by dividing the unit length of the crystal growth from L-1 to L by the corresponding time interval.

[0065] The diameter growth rate when the crystal length is the preset length can be obtained by dividing the diameter growth length corresponding to the growth from L-1 to L by the corresponding time interval.

[0066] The crucible lifting speed refers to the speed at which the crucible rises. In the shoulder-setting stage of the Czochralski method, polycrystalline silicon raw materials are placed in the crucible and heated to form polycrystalline silicon melt.

[0067] The main power refers to the power of the main heater; the main power reduction is the current main power minus the main power at the beginning of the shoulder stage; the main power reduction corresponding to each unit length of crystal growth within the preset length range before the preset length is the main power corresponding to each unit length of crystal growth within the preset length range minus the main power at the beginning of the shoulder stage.

[0068] The diameter growth rate prediction model is obtained through a first model training method, which includes the following steps:

[0069] Step S210: For the selected crystal specification, acquire production data of multiple crystals during the shoulder-forming stage, including: when the crystal grows to a preset length according to the standard operating procedure (SOP), acquire the pulling speed, diameter growth rate, crucible lifting speed, and main power reduction corresponding to each unit length of crystal growth within the preset length interval before the preset length, as input data for the diameter growth rate prediction model; wherein the preset length interval is less than or equal to the preset length; when the crystal grows to a preset length + one unit length according to the standard operating procedure (SOP), acquire the diameter growth rate corresponding to the crystal length being the preset length + one unit length, as output data for the diameter growth rate prediction model.

[0070] The diameter growth rate prediction model specifically employs a long short-term memory network, namely LSTM.

[0071] In one specific embodiment, the preset length is 10 mm to 20 mm.

[0072] In one specific embodiment, the preset length range is 10 mm to 20 mm.

[0073] In one specific embodiment, the unit length is 1 mm to 2 mm.

[0074] In a specific embodiment, the preset length is L, the preset length range is ΔL, and the unit length is 1 mm; assuming the preset length L = 10 mm and the preset length range ΔL = 10 mm, then when the crystal grows to the preset length L = 10 mm according to the SOP control, the input data of the diameter growth rate prediction model is as shown in formula (1):

[0075]

[0076] The preset length L = 10 millimeters.

[0077] S l (1)S l (2)…S l (L) represents the pulling speed of the crystal per unit length growth within the preset length interval before the preset length when the crystal grows to the preset length.

[0078] S d (1)S d (2)…S d (L) represents the diameter growth rate of the crystal per unit length within the preset length interval before the preset length when the crystal grows to the preset length.

[0079] S c (1)S c (2)…S c (L) represents the crucible lifting speed corresponding to each unit length of crystal growth within the preset length interval before the preset length when the crystal grows to the preset length.

[0080] P desc (1)P desc (2)…P desc (L) represents the decrease in main power for each unit length of crystal growth within the preset length range before the preset length when the crystal grows to the preset length.

[0081] S l (1) S d (1) S c (1) and P desc In (1), “1” represents a unit length.

[0082] The pulling speed corresponding to each unit length of crystal growth is obtained by dividing each unit length of crystal growth by the corresponding time interval.

[0083] The diameter growth rate per unit length of crystal growth is obtained by dividing the diameter growth length per unit length of crystal growth by the corresponding time interval.

[0084] The diameter growth rate when the crystal length is a preset length plus one unit length is obtained by dividing the diameter growth length when the crystal length grows from the preset length to the preset length plus one unit length by the corresponding time interval.

[0085] In some embodiments, the crystal length and crystal diameter can be obtained by a real-time measurement method based on image processing, thereby obtaining the crystal growth length per unit length and the diameter growth length corresponding to the crystal growth length per unit length.

[0086] The crucible lifting speed refers to the speed at which the crucible rises. In the shoulder-setting stage of the Czochralski method, polycrystalline silicon raw materials are placed in the crucible and heated to form polycrystalline silicon melt.

[0087] The main power refers to the power of the main heater; the main power reduction is the current main power minus the main power at the beginning of the shoulder stage; the main power reduction corresponding to each unit length of crystal growth within the preset length range before the preset length is the main power corresponding to each unit length of crystal growth within the preset length range minus the main power at the beginning of the shoulder stage.

[0088] Step S220: Train the diameter growth rate prediction model based on the input and output data of the diameter growth rate prediction model; the diameter growth rate prediction model is used to predict the diameter growth rate when the crystal length is a preset length + one unit length.

[0089] In this step, for example, production data of 100 crystals during the shoulder-building stage is obtained. Specifically, for each crystal, when it grows to a preset length according to the SOP, the pulling speed, diameter growth rate, crucible lifting speed, and main power reduction of the crystal per unit length growth within the preset length interval before the preset length are obtained as input data for the diameter growth rate prediction model. For each crystal, when it grows to a preset length + one unit length according to the SOP, the diameter growth rate corresponding to the crystal length of the preset length + one unit length is obtained as output data for the diameter growth rate prediction model. Then, the long short-term memory network is trained.

[0090] Since the diameter growth rate is not only trend-based, but also affected by production data such as pulling speed, crucible lifting speed, and main heating power reduction when the thermal field changes, training a diameter growth rate prediction model can fully utilize the trend of each production data and the mutual influence relationship between them and the diameter growth rate, thereby improving the accuracy of diameter growth rate prediction when the thermal field fluctuates.

[0091] The speed prediction model is obtained through a second model training method, which includes the following steps:

[0092] Step S310: For the selected crystal specification, obtain production data of multiple crystals during the shoulder-forming stage, including: when the crystal grows to a preset length + one unit length according to the standard operating procedure (SOP), obtain the pulling speed corresponding to the crystal length being the preset length + one unit length and the pulling speed corresponding to the crystal length being the preset length, and calculate the pulling speed difference; obtain the diameter growth rate corresponding to the crystal length being the preset length + one unit length and the diameter growth rate corresponding to the crystal length being the preset length, and calculate the diameter growth rate difference;

[0093] The speed difference is shown in formula (2):

[0094] S l (L+1)-S l (L)(2)

[0095] Among them, S l (L+1) represents the pulling speed when the crystal length is the preset length plus one unit length, S l (L) represents the pulling speed corresponding to the crystal length being the preset length; S is obtained by dividing the unit length grown from L to L+1 by the corresponding time interval. l (L+1); S is obtained by dividing the unit length of crystal growth from L-1 to L by the corresponding time interval. l (L); L represents the preset length; the "1" here represents one unit length;

[0096] The difference in diameter growth rate is shown in formula (3):

[0097] S d (L+1)-S d (L)(3)

[0098] Among them, S d (L+1) represents the diameter growth rate when the crystal length is a preset length plus one unit length, S d (L) represents the diameter growth rate when the crystal length is the preset length; S is obtained by dividing the diameter growth length corresponding to the crystal length growing from L to L+1 by the corresponding time interval. d (L+1); The diameter growth length corresponding to the crystal length growing from L-1 to L, divided by the corresponding time interval, gives S. d (L); L represents the preset length; here "1" represents one unit length.

[0099] Step S320: Fit the relationship between the difference in pulling speed and the difference in diameter growth rate to obtain the relationship expression; as shown in formula (4):

[0100] S l (L+1)-S l(L)=a*[S d (L+1)-S d (L)]+b (4)

[0101] The relational expression includes parameters a and b; a is the weight coefficient (i.e., slope), and b is the bias term (i.e., intercept);

[0102] Step S330: Solve the parameters in the relational expression using the least squares method to establish a pulling speed prediction model; the pulling speed prediction model is used to calculate the pulling speed prediction value corresponding to the crystal length being a preset length + one unit length; the pulling speed prediction model is shown in formula (5):

[0103]

[0104] Among them, S l (L) represents the pulling speed corresponding to the crystal length being the preset length. This represents the predicted pulling speed when the crystal length is a preset length plus one unit length; S d (L) represents the diameter growth rate when the crystal length is the preset length; S d (L+1) represents the diameter growth rate when the crystal length is the preset length plus one unit length.

[0105] Compared to adjusting the pulling speed using only SOP, this application uses a pulling speed prediction model to calculate the predicted pulling speed for the next unit length. When there are short-term fluctuations in the thermal field, the calculated predicted pulling speed can accurately match the diameter growth rate, thereby avoiding the situation of shoulder breakage due to excessive or insufficient pulling speed adjustment.

[0106] This invention also provides a shoulder release control device based on pulling speed, such as... Figure 2 As shown, it includes:

[0107] The selection module is used to select the corresponding pre-configured diameter growth rate prediction model and pulling speed prediction model for the selected crystal size.

[0108] The diameter growth rate prediction module is used during the shoulder-forming stage to obtain the pulling speed, diameter growth rate, crucible lifting speed, and main power reduction of the crystal per unit length within a preset length interval before the preset length, when the crystal grows to a preset length according to the standard operating procedure (SOP). The preset length interval is less than or equal to the preset length. This data is then used as input data for the diameter growth rate prediction model, which predicts the diameter growth rate when the crystal length is the preset length plus one unit length.

[0109] The pulling speed prediction module is used during the shoulder-forming stage to obtain the pulling speed and diameter growth rate corresponding to the crystal length when it grows to a preset length according to the standard operating procedure (SOP). The predicted values ​​of the pulling speed, diameter growth rate, and diameter growth rate when the crystal length is the preset length plus one unit length are used as input data to the pulling speed prediction model. The pulling speed prediction model then calculates the predicted pulling speed when the crystal length is the preset length plus one unit length.

[0110] The pulling speed control module controls the pulling speed when the crystal length is a preset length plus one unit length, based on the predicted pulling speed value.

[0111] like Figure 3 As shown, this embodiment of the invention also provides an electronic device, including: a processor and a memory; the processor and the memory communicate with each other, for example, by being connected and communicating with each other via a communication bus; the memory stores a computer program; the processor is used to run the computer program, and the computer program executes the steps of the shoulder release control method based on pull speed as described above when it runs; the processor may be a CPU, or other general-purpose processor, digital signal processor (DSP), application specific integrated circuit (ASIC), field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or combinations of the above-mentioned chips, devices, or circuits; the memory may include volatile memory, such as random access memory; the memory may also include non-volatile memory, such as flash memory, hard disk or solid-state drive; the memory may also include combinations of the above-mentioned types of memory.

[0112] This invention also proposes a storage medium storing a computer program configured to execute the steps of the pull-speed-based shoulder control method described above during runtime. The storage medium can be a magnetic disk, optical disk, read-only memory (ROM), random access memory (RAM), flash memory, hard disk drive (HDD), or solid-state drive (SSD), etc.; the storage medium may also include combinations of the above types of memory.

[0113] Finally, it should be noted that the above specific embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the 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, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A shoulder-forming control method based on pulling speed, the method being used to control the shoulder-forming process of a crystal during the shoulder-forming stage of the Czochralski method, characterized in that, The method includes: For the selected crystal size, select the corresponding pre-configured diameter growth rate prediction model and pulling speed prediction model; During the shoulder-forming stage, when the crystal grows to a preset length according to the standard operating procedure (SOP), the pulling speed, diameter growth rate, crucible lifting speed, and main power reduction for each unit length of crystal growth within the preset length interval before the preset length are obtained, wherein the preset length interval is less than or equal to the preset length; then, these are used as input data for the diameter growth rate prediction model, and the diameter growth rate prediction value corresponding to the crystal length being the preset length + one unit length is predicted by the diameter growth rate prediction model. During the shoulder-forming stage, when the crystal grows to a preset length according to the standard operating procedure (SOP), the pulling speed and diameter growth rate corresponding to the preset crystal length are obtained. The pulling speed, diameter growth rate, and predicted diameter growth rate corresponding to the preset crystal length plus one unit length are used as input data for the pulling speed prediction model. The pulling speed prediction model is then used to calculate the predicted pulling speed corresponding to the preset crystal length plus one unit length. The pulling speed is controlled based on the predicted pulling speed value when the crystal length is a preset length plus one unit length.

2. The shoulder release control method based on stretching speed as described in claim 1, characterized in that, The preset length is 10 mm to 20 mm.

3. The shoulder release control method based on stretching speed as described in claim 1, characterized in that, The preset length range is 10 mm to 20 mm.

4. The shoulder release control method based on stretching speed as described in claim 1, characterized in that, The unit length is 1 mm to 2 mm.

5. The shoulder release control method based on pulling speed as described in claim 1, characterized in that, The diameter growth rate prediction model is obtained through a first model training method, which includes the following steps: For a selected crystal specification, production data of multiple crystals during the shoulder-forming stage is obtained, including: when the crystal grows to a preset length according to the standard operating procedure (SOP), the pulling speed, diameter growth rate, crucible lifting speed, and main power reduction of the crystal per unit length growth within the preset length interval before the preset length are obtained as input data for the diameter growth rate prediction model; wherein the preset length interval is less than or equal to the preset length; when the crystal grows to a preset length + one unit length according to the standard operating procedure (SOP), the diameter growth rate corresponding to the crystal length being the preset length + one unit length is obtained as output data for the diameter growth rate prediction model; The diameter growth rate prediction model uses a Long Short-Time Memory (LSTM) network. The diameter growth rate prediction model is trained based on the input and output data of the diameter growth rate prediction model; the diameter growth rate prediction model is used to predict the diameter growth rate when the crystal length is a preset length + one unit length.

6. The shoulder release control method based on stretching speed as described in claim 1, characterized in that, The speed prediction model is obtained through a second model training method, which includes the following steps: For the selected crystal specification, obtain production data of multiple crystals during the shoulder-forming stage, including: when the crystal grows to a preset length + one unit length according to the standard operating procedure (SOP), obtain the pulling speed and the pulling speed difference when the crystal length is the preset length + one unit length; obtain the diameter growth rate and the diameter growth rate when the crystal length is the preset length + one unit length, and calculate the diameter growth rate difference. The relationship between the difference in stretching speed and the difference in diameter growth rate was fitted to obtain the relationship expression; The parameters in the relational expression are solved using the least squares method to establish a pulling speed prediction model; the pulling speed prediction model is used to calculate the pulling speed prediction value corresponding to a crystal length of a preset length plus one unit length.

7. The shoulder release control method based on stretching speed as described in claim 6, characterized in that, The relational expression is shown in formula (4): S l (L+1)-S l (L)=a*[S d (L+1)-S d (L)]+b (4) Among them, S l (L+1) represents the pulling speed when the crystal length is the preset length plus one unit length, S l (L) represents the pulling speed corresponding to the crystal length being the preset length; Among them, S d (L+1) represents the diameter growth rate when the crystal length is a preset length plus one unit length, S d (L) represents the diameter growth rate when the crystal length is the preset length; The relational expression includes parameters a and b; a is the weight coefficient, and b is the bias term; The speed prediction model is shown in formula (5): Among them, S l (L) represents the pulling speed corresponding to the crystal length being the preset length. This represents the predicted pulling speed when the crystal length is a preset length plus one unit length.

8. A shoulder release control device based on pulling speed, characterized in that, include: The selection module is used to select the corresponding pre-configured diameter growth rate prediction model and pulling speed prediction model for the selected crystal size. The diameter growth rate prediction module is used during the shoulder-forming stage to obtain, when the crystal grows to a preset length according to the standard operating procedure (SOP), the pulling speed, diameter growth rate, crucible lifting speed, and main power reduction corresponding to each unit length of crystal growth within a preset length interval before the preset length, wherein the preset length interval is less than or equal to the preset length; then, it is used as input data for the diameter growth rate prediction model, which predicts the diameter growth rate when the crystal length is the preset length + one unit length. The pulling speed prediction module is used during the shoulder-forming stage to obtain the pulling speed and diameter growth rate corresponding to the crystal length when it grows to a preset length according to the standard operating procedure (SOP). The predicted values ​​of the pulling speed, diameter growth rate, and diameter growth rate when the crystal length is the preset length plus one unit length are used as input data to the pulling speed prediction model. The pulling speed prediction model then calculates the predicted pulling speed value when the crystal length is the preset length plus one unit length. The pulling speed control module controls the pulling speed when the crystal length is a preset length plus one unit length, based on the predicted pulling speed value.

9. An electronic device, characterized in that, include: Memory, which stores computer programs; A processor for running the computer program, which, when running, performs the steps of the shoulder release control method based on pulling speed as described in any one of claims 1 to 7.

10. A storage medium, characterized in that, The storage medium stores a computer program configured to execute the steps of the shoulder release control method based on pulling speed as described in any one of claims 1 to 7 when the computer program is run.

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