Polycrystalline silicon deposition air inlet device based on growth characteristics of silicon core rod and control method

Abstract

The invention relates to the technical field of polycrystalline silicon deposition used as a main raw material in the semiconductor or solar industry, in particular to a polycrystalline silicon deposition air inlet device based on growth characteristics of a silicon core rod and a control method. The control method comprises the following steps: determining growth abnormal area data of the silicon core rod and overall growth rate data of the silicon core rod based on the surface temperature distribution uniformity degree of the silicon core rod in a first preset time length and / or the growth uniformity degree of the silicon core rod in a second preset time length; determining to control air intake by a local control method or an integral control method based on whether the growth abnormal area with the non-overlapped area and the growth abnormal area after space splicing cover the silicon core rod for a circle or not and a comparison result of the integral growth rate of the silicon core rod and a preset integral growth rate; according to the invention, the control accuracy of the air inlet device is improved by improving the analysis accuracy of the growth characteristics of the silicon core rod.

Description

Technical Field

[0001] The present invention relates to the technical field of polysilicon deposition used as the main raw material in the semiconductor or solar energy industry, and particularly to a polysilicon deposition gas inlet device and a control method based on the growth characteristics of a silicon core rod. Background Art

[0002] To manufacture polycrystalline silicon (also known as polysilicon) used as the main raw material in the semiconductor or solar energy industry, its preparation methods include the Siemens method, the fluidized bed method, the VLD (vapor-liquid deposition) method, and the method of directly refining metallurgical grade silicon. Among them, the most commonly used method in large quantities is the Siemens method. This method is to thermally decompose a mixed raw material gas of chlorosilane or monosilane and hydrogen and deposit it on a silicon core rod to manufacture polycrystalline silicon; during the production process of polysilicon, the growth quality of the silicon core rod has a crucial impact on the performance and quality of the final product. Polysilicon deposition is a complex physico-chemical process, and the performance and control method of the gas inlet device directly affect the temperature distribution on the surface of the silicon core rod and the growth of the silicon core rod. Traditional control methods for gas inlet devices are often relatively rough and cannot accurately adjust in real time according to the growth characteristics of the silicon core rod.

[0003] For example, Chinese Patent Application Publication No.: CN115132579A discloses a method for controlling the in-furnace uniformity of a polysilicon layer, including the steps of: placing a plurality of substrates in a polysilicon deposition furnace, and at least distributing them at the furnace mouth and the furnace tail in the furnace; adjusting the conditions in the polysilicon deposition furnace to polysilicon deposition conditions, introducing a gaseous polysilicon precursor into the polysilicon deposition furnace for reaction and deposition in a manner of simultaneously introducing gas from both ends of the furnace mouth and the furnace tail, and forming a polysilicon layer on the surface including the P+ channel and the connection area; at least measuring the thickness of the polysilicon layer formed at the furnace mouth and the furnace tail and obtaining the in-furnace uniformity value. When the in-furnace uniformity value of the polysilicon layer thickness is greater than a predetermined value T, heating the furnace tail or cooling the furnace mouth; the control method of this application can significantly improve the performance stability of the polysilicon field plate during mass production, thereby improving its yield, production rate, and reducing its cost.

[0004] However, the prior art has the problem that the analysis of polysilicon growth parameters is not accurate enough, resulting in inaccurate regulation of gas entry and uneven growth of the silicon core rod after deposition. Summary of the Invention

[0005] Therefore, the present invention provides a polysilicon deposition gas inlet device and a control method based on the growth characteristics of a silicon core rod to overcome the problem in the prior art that the inaccurate analysis of polysilicon growth parameters leads to inaccurate regulation of gas entry and uneven growth of the silicon core rod after deposition.

[0006] To achieve the above objectives, the present invention provides a method for controlling a polysilicon deposition gas inlet device based on silicon core rod growth characteristics, comprising: Acquire surface temperature data of the silicon core rod, growth data of the silicon core rod, and air intake data of the air intake device during the deposition process; Determining to obtain abnormal growth area data of the silicon core rod and overall growth rate data of the silicon core rod based on the uniformity of surface temperature distribution of the silicon core rod within the first preset time period and / or the uniformity of growth of the silicon core rod within the second preset time period; determining whether to spatially splice the abnormal growth areas based on whether there are non-overlapping areas in the abnormal growth areas; Determining whether to control the air intake by a local control method or an overall control method based on a comparison result of the growth abnormality region with non-overlapping regions and the coverage of the growth abnormality region after spatial splicing, and the overall growth rate of the silicon core rod and a preset overall growth rate; Based on whether there are conflicting abnormal characteristics in the local growth abnormal area, it is determined to adjust the intake flow or intake angle of the intake device corresponding to the local growth abnormal area, or based on the consistency of the abnormal characteristics of the overall growth area, it is determined to adjust the distribution position or distribution spacing of the overall intake device.

[0007] Furthermore, determining to obtain data of abnormal growth areas of the silicon core rod or obtaining data of the overall growth rate of the silicon core rod includes: If the surface temperature distribution uniformity of the silicon core rod within the first preset time period is greater than or equal to the preset distribution uniformity or the growth uniformity of the silicon core rod within the second preset time period is greater than or equal to the preset growth uniformity, determining to obtain the abnormal growth area data of the silicon core rod; If the surface temperature distribution uniformity of the silicon core rod within the first preset time period is less than the preset distribution uniformity and the growth uniformity of the silicon core rod within the second preset time period is less than the preset growth uniformity, it is determined to obtain the overall growth rate data of the silicon core rod.

[0008] Furthermore, calculating the uniformity of the surface temperature distribution of the silicon core rod within the first preset time period includes: Select several sections at equal intervals along the axial direction of the silicon core rod, and select multiple points at equal angles in the circumferential direction on each section as temperature monitoring points; Acquire the temperature data of each monitoring point collected in real time within a first preset time period, and record the temperature value of each point at each moment to form a time series temperature data set; Calculating the average temperature of the silicon core rod surface within a first preset time period, and calculating the deviation between the temperature value of each monitoring point and the average temperature; The standard deviation of the temperature deviations of all monitoring points is calculated to obtain the uniformity of the surface temperature distribution of the silicon core rod within the first preset time period.

[0009] Further, calculating the growth uniformity of the silicon core rod within the second preset time period includes: Select a number of cross-sections at equal intervals along the axial direction of the silicon core rod, and select multiple points at equal angles in the circumferential direction on each cross-section as growth uniformity monitoring points; Regularly measure the growth parameters of the silicon core rod at each monitoring point within the second preset time period, and record the growth data of each point at each moment to form a time series of growth data; Process the growth data of all monitoring points within the second preset time period to calculate the diameter change rate on the surface of the silicon core rod within this time period; Calculate the deviation between the diameter change rate of each monitoring point and the average diameter change rate; Calculate the standard deviation of the diameter change rate deviations of all monitoring points to obtain the growth uniformity of the silicon core rod within the second preset time period.

[0010] Further, determining whether to spatially splice the growth abnormal regions includes: If there are non-overlapping regions in the growth abnormal regions, determine that it is necessary to spatially splice the growth abnormal regions; If there are no non-overlapping regions in the growth abnormal regions, determine that it is not necessary to spatially splice the growth abnormal regions.

[0011] Further, spatially splicing the growth abnormal regions includes: Establish a three-dimensional coordinate system with the central axis of the silicon core rod as the coordinate axis; Determine the boundary point coordinates of each growth abnormal region and its range parameters in the circumferential and axial directions through measurement or calculation; Based on the boundary point coordinates and range parameters of each growth abnormal region, perform boundary matching to identify the connection relationship between adjacent growth abnormal regions; Based on the boundary point coordinates and connection relationship of each growth abnormal region, spatially splice the growth abnormal regions to form a continuous region.

[0012] Further, determining to control the intake air by a local control method or an overall control method includes: If the growth abnormal regions with non-overlapping regions and the growth abnormal regions after spatial splicing do not cover the entire circumference of the silicon core rod and the overall growth rate of the silicon core rod is greater than or equal to the preset overall growth rate, determine to control the intake air by a local control method; If either the growth abnormal regions with non-overlapping regions or the growth abnormal regions after spatial splicing cover the entire circumference of the silicon core rod or the overall growth rate of the silicon core rod is less than the preset overall growth rate, determine to control the intake air by an overall control method.

[0013] Furthermore, determining to adjust the intake flow rate or intake angle of the intake device corresponding to the local abnormal growth area includes: If the local abnormal growth region has conflicting abnormal features, determining to adjust the intake angle of the intake device corresponding to the local abnormal growth region; If the local abnormal growth region does not have conflicting abnormal features, it is determined to adjust the intake flow of the intake device corresponding to the local abnormal growth region.

[0014] Furthermore, determining and adjusting the distribution position or distribution spacing of the integral air intake device includes: If the degree of consistency of the abnormal characteristics of the entire growth area is less than or equal to a preset degree of consistency, determining to adjust the distribution position of the entire air intake device; If the degree of consistency of the abnormal characteristics of the entire growth area is greater than a preset degree of consistency, it is determined to adjust the distribution spacing of the entire air intake device.

[0015] A polysilicon deposition air inlet device applied to the polysilicon deposition air inlet device control method based on silicon core rod growth characteristics, comprising: An air inlet pipe, comprising a closed end located in the deposition furnace, an interface end connected to the silane air inlet, an outer pipe and an inner pipe, wherein the outer pipe is sleeved on the inner pipe, the inner pipe is used to circulate silane gas, and a sealed cavity is formed between the outer pipe and the inner pipe for heat insulation; Exhaust holes are evenly spaced along the extension direction of the air inlet pipe, with the opening direction inclined downward at 30°-60° to the axis of the silicon core rod, for uniform gas distribution; A connecting piece is located at the interface end and is used to connect the air inlet pipe to the silane air inlet.

[0016] Compared with the prior art, the beneficial effect of the present invention lies in that the present invention can accurately judge the current growth status of the silicon core rod by comparing the uniformity of the surface temperature distribution of the silicon core rod within the first preset time and the uniformity of the growth of the silicon core rod within the second preset time with the corresponding preset values. When the conditions of "the temperature distribution uniformity is greater than or equal to the preset distribution uniformity, or the growth uniformity is greater than or equal to the preset growth uniformity" are met, the data of the abnormal growth area is determined to be obtained, which can quickly lock the local abnormal growth area and conduct targeted analysis and processing of local problems in time; when "the temperature distribution uniformity is less than the preset distribution uniformity and the growth uniformity is less than the preset growth uniformity", the overall growth rate data is determined to be obtained, which helps to grasp the overall growth trend of the silicon core rod from a macro perspective, discover problems in the overall growth process, and avoid ignoring overall growth abnormalities due to local misjudgment. The above method improves the accuracy of the analysis of polysilicon growth parameters and thus realizes precise control of gas entry to obtain silicon core rods with uniform growth.

[0017] Furthermore, by establishing a three-dimensional coordinate system with the central axis of the silicon core rod as the coordinate axis, the present invention can accurately determine the spatial coordinate positions of each growth abnormal region on the silicon core rod, including the ranges in the axial and circumferential directions, and precisely obtain the specific distribution of the growth abnormal regions on the silicon core rod. When there are non-overlapping regions, a spatial splicing operation is performed to integrate the scattered growth abnormal regions into a continuous region, avoiding repeated analysis and processing caused by the dispersion of the growth abnormal regions, greatly improving the processing efficiency of the growth abnormal regions, reducing the labor and time costs. By judging whether there are non-overlapping regions in the growth abnormal regions, it is decided whether to perform spatial splicing, which helps to reasonably allocate production resources. For the case where there are no non-overlapping regions, there is no need to perform splicing operations, and resources can be concentrated on targeted treatment of existing growth abnormal regions; while for the case where there are non-overlapping regions that need to be spliced, after splicing, the overall scale and shape of the growth abnormal regions can be more clearly understood, so as to more scientifically plan and allocate resources. Through the above method, the accuracy of the analysis of polysilicon growth parameters is improved, and then the precise control of gas entry is realized to obtain a silicon core rod with uniform growth.

[0018] Furthermore, by comprehensively considering the coverage range of the growth abnormal regions and the overall growth rate, the present invention can accurately judge the types and degrees of the growth abnormalities of the silicon core rod. When neither the non-overlapping regions nor the growth abnormal regions after splicing cover the entire circumference of the silicon core rod and the overall growth rate meets the standard, a local control method is adopted, which can precisely focus on the local growth abnormal regions, avoid unnecessary interference with the normal growth regions, and reduce the waste of energy and raw materials; when the growth abnormal regions cover the entire circumference or the overall growth rate is insufficient, the overall control method is timely adopted to make adjustments from a macroscopic level to ensure the consistency of the growth environment of the entire silicon core rod, effectively solve the global growth problems, and improve the matching degree between the control strategy and the actual abnormal scenario. This method avoids the "one-size-fits-all" control method and flexibly selects local or overall control according to the actual situation. When there is local abnormality and good overall growth, the local control only adjusts the gas intake for the growth abnormal regions without large-scale modification of the entire gas intake system, reducing the equipment adjustment time and energy consumption and improving the production efficiency; in the case of overall abnormality, the overall control can quickly adjust the global gas intake conditions to make the growth of the silicon core rod return to normal as soon as possible, shorten the abnormal processing time, and avoid the spread of abnormalities caused by untimely local control, thereby improving the resource utilization efficiency and reducing the production cost. Through the above method, the accuracy of the analysis of polysilicon growth parameters is improved, and then the precise control of gas entry is realized to obtain a silicon core rod with uniform growth.

[0019] Furthermore, the present invention provides an accurate decision-making basis for adjusting the intake device by clearly distinguishing whether there are conflicting abnormal features in the locally growing abnormal area. When there are conflicting abnormal features, adjusting the intake angle can target the conflicting growth conditions within the area and focus on improving the weak abnormal features, such as increasing the concentration of reaction gas at the slow-growing area and enhancing heat transfer at the low-temperature area, so as to achieve targeted regulation of complex abnormal situations. When there are no conflicting abnormal features, adjusting the intake flow rate based on the comparison between the overall growth rate and the non-growing abnormal area can effectively solve the problem of overall growth being too slow or too fast. For the local area without conflicting abnormal features, the adjustment amount of the intake flow rate is accurately calculated according to the growth rate difference, avoiding over-supplying or under-supplying gas. While ensuring the growth quality of the silicon core rod, unnecessary consumption of reaction gas is reduced, and production costs are lowered. For the area with conflicting abnormal features, adjusting the intake angle can more reasonably distribute the gas flow direction. Through the above methods, the accuracy of analyzing the polysilicon growth parameters is improved, and thus the accurate regulation of gas entry is achieved to obtain a silicon core rod with uniform growth.

[0020] Furthermore, the present invention can more accurately address the problems that occur during the overall growth process of the silicon core rod by selecting the method of adjusting the intake device based on the degree of consistency of the abnormal features in the overall growth area. When the degree of consistency of the abnormal features is low, adjusting the distribution position can accurately direct the gas to the area with poor growth. When the degree of consistency is high, adjusting the distribution spacing can optimize the gas distribution as a whole, enabling the reaction gas to more effectively participate in the deposition process of the silicon core rod, reducing the uneven growth situation, thereby increasing the growth rate of the silicon core rod, improving production efficiency, reducing the differences in growth rate, temperature, and gas flow rate at different parts of the silicon core rod, enhancing the overall growth uniformity of the silicon core rod, and reducing the internal stress and defects caused by uneven growth, thus improving the quality and performance of the silicon core rod. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is the working flow chart of the control method for the polysilicon deposition intake device based on the growth characteristics of the silicon core rod in the embodiment of the present invention; Figure 2 is the working flow chart of determining the uniformity degree of the surface temperature distribution of the silicon core rod in the control method for the polysilicon deposition intake device based on the growth characteristics of the silicon core rod in the embodiment of the present invention; Figure 3 is the working flow chart of determining whether to spatially splice the growth abnormal area in the control method for the polysilicon deposition intake device based on the growth characteristics of the silicon core rod in the embodiment of the present invention; Figure 4 is the structural schematic diagram of the silicon core rod with a growth abnormal area in the control method for the polysilicon deposition intake device based on the growth characteristics of the silicon core rod in the embodiment of the present invention; Figure 5Schematic diagram of a polysilicon deposition intake device for the control method of the polysilicon deposition intake device applied to the embodiments of the present invention based on the growth characteristics of a silicon ingot rod; In the figure, 1 is the closed end; 2 is the exhaust hole; 3 is the interface end; 4 is the connecting piece; 5 is the outer tube; 6 is the inner tube; 7 is the first growth abnormal area; 8 is the second growth abnormal area; 9 is the central axis of the silicon ingot rod. Detailed implementation manners

[0022] In order to make the objectives and advantages of the present invention clearer and more understandable, the present invention will be further described below in conjunction with embodiments; it should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0023] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are only used to explain the technical principles of the present invention and do not limit the protection scope of the present invention.

[0024] It should be noted that in the description of the present invention, the terms indicating directions or positional relationships such as "upper", "lower", "left", "right", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings. This is only for the convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention.

[0025] In addition, it should be noted that in the description of the present invention, unless otherwise clearly defined and limited, the terms "installation", "connection", and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0026] Please refer to Figures 1-4 as shown Figure 1 is the working flowchart of the control method of the polysilicon deposition intake device based on the growth characteristics of the silicon ingot rod in the embodiments of the present invention; Figure 2 is the working flowchart of determining the uniformity of the surface temperature distribution of the silicon ingot rod in the control method of the polysilicon deposition intake device based on the growth characteristics of the silicon ingot rod in the embodiments of the present invention; Figure 3 is the working flowchart of determining whether to perform spatial splicing on the growth abnormal area in the control method of the polysilicon deposition intake device based on the growth characteristics of the silicon ingot rod in the embodiments of the present invention; Figure 4 is the structural schematic diagram of the silicon ingot rod with a growth abnormal area in the control method of the polysilicon deposition intake device based on the growth characteristics of the silicon ingot rod in the embodiments of the present invention.

[0027] The control method for the intake device of polysilicon deposition based on the growth characteristics of a silicon ingot in an embodiment of the present invention includes: Step S1, obtaining the surface temperature data of the silicon ingot, the growth data of the silicon ingot, and the intake data of the intake device during the deposition process; Step S2, determining the growth abnormal area data of the silicon ingot and the overall growth rate data of the silicon ingot based on the uniformity degree of the surface temperature distribution of the silicon ingot within a first preset time period and / or the growth uniformity degree of the silicon ingot within a second preset time period; Step S3, determining whether to perform spatial splicing on the growth abnormal area based on whether there is an un-overlapped area in the growth abnormal area; Step S4, determining to control the intake with a local control method or an overall control method based on the coverage range of the growth abnormal area with un-overlapped areas and the growth abnormal area after spatial splicing, and the comparison result between the overall growth rate of the silicon ingot and the preset overall growth rate; Step S5, determining to adjust the intake flow rate or intake angle of the intake device corresponding to the local growth abnormal area based on whether there are conflict abnormal characteristics in the local growth abnormal area, or determining to adjust the distribution position or distribution spacing of the overall intake device based on the consistency degree of the abnormal characteristics of the overall growth area.

[0028] In the embodiment of the present invention, the growth data of the silicon ingot includes but is not limited to "diameter change rate data, growth rate data, and growth abnormal area data", the intake data of the intake device includes but is not limited to "gas flow rate data, gas temperature data, and intake device distribution position data", and the growth abnormal area is the area with uneven surface temperature distribution of the silicon ingot and the area with uneven growth of the silicon ingot.

[0029] In the embodiments of the present invention, the initial distribution position of the intake device can determine the axial and radial distribution positions of the intake device according to the length, diameter, and target growth shape (such as cylindrical, conical) of the silicon core rod. For example, according to the symmetry of the deposition furnace, a uniform angular distribution is adopted (such as arranging an intake device every 60°); the initial distribution angle of the intake device can determine the tilt angle (such as 30°-60°) of the intake device by calculating or simulating the diffusion angle of silane gas (such as chlorosilane), so that the gas can cover the target growth area. The angle should avoid directly impacting the surface of the silicon core rod vertically to prevent uneven growth caused by local turbulence. The initial value can be set based on the angle with the best gas distribution uniformity in historical deposition experiments; the initial intake flow rate of the intake device can calculate the required gas flow rate per unit time (such as 10-20 L / min) according to the reduction and deposition efficiency of chlorosilane, and is associated with the preset overall growth rate of the silicon core rod (such as 0.5 mm / h). The required intake speed is inversely deduced through a gas-growth rate model (such as the Arrhenius equation). The initial distribution spacing of the intake device can calculate the gas diffusion radius (such as CFD simulation) to ensure that there is partial overlap (the overlap rate is about 20%-30%) in the airflow fields of adjacent intake devices, avoiding dead corners. Based on the previous experimental data, the spacing that minimizes the standard deviation of the temperature field and growth rate is selected (such as the axial spacing is 15-30 cm, and the circumferential spacing is adjusted according to the number of intake devices).

[0030] Specifically, in step S2, when determining to obtain data on the growth abnormal area of the silicon core rod or obtain data on the overall growth rate of the silicon core rod, it is determined to obtain data on the growth abnormal area of the silicon core rod or obtain data on the overall growth rate of the silicon core rod according to the uniformity of the surface temperature distribution of the silicon core rod within the first preset time period and / or the growth uniformity of the silicon core rod within the second preset time period; When the uniformity of the surface temperature distribution of the silicon core rod within the first preset time period is greater than or equal to the preset distribution uniformity or the growth uniformity of the silicon core rod within the second preset time period is greater than or equal to the preset growth uniformity, it is determined to obtain data on the growth abnormal area of the silicon core rod; When the uniformity of the surface temperature distribution of the silicon core rod within the first preset time period is less than the preset distribution uniformity and the growth uniformity of the silicon core rod within the second preset time period is less than the preset growth uniformity, it is determined to obtain data on the overall growth rate of the silicon core rod.

[0031] In the embodiments of the present invention, the first preset duration can be determined by collecting a large amount of historical data during the past polysilicon deposition production process, including the data on the uniformity of the surface temperature distribution of the silicon core rod in different batches of production and the corresponding monitoring durations. Analyze the monitoring duration corresponding to the stable state of the surface temperature distribution uniformity of the silicon core rod when qualified products are produced (i.e., no growth abnormalities caused by temperature distribution problems are found in subsequent inspections). Statistically analyze the central tendency (such as the average value) of these duration data, and combine production experience and actual requirements to determine the first preset duration. For example, a large polysilicon production enterprise has collected production data from the past 1000 batches. Analyze the uniformity of the surface temperature distribution of the silicon core rod in each batch of production, and find the monitoring duration when the temperature distribution uniformity reaches a stable state and no growth abnormalities are caused by temperature problems in each batch. After statistics, the average value of these duration data is 55 minutes. Considering the stability of the equipment and the product quality requirements in actual production, in order to ensure the accurate judgment of the surface temperature distribution uniformity of the silicon core rod, the first preset duration is determined to be 55 minutes. In subsequent production, if the equipment is upgraded or the process parameters change significantly, the first preset duration is re-evaluated and adjusted according to the new historical data; the second preset duration can be determined according to the growth stage of the silicon core rod. For example, in the initial stage of the silicon core rod growth (0-20 hours), the value is 2 hours; in the middle stage of growth (20-65 hours), the value is 4 hours; in the later stage of growth (65-85 hours), the value is 6 hours. The preset distribution uniformity is the average value of the surface temperature distribution uniformity of the silicon core rod when no growth abnormal areas appear on the silicon core rod under the same deposition conditions within a number of first preset durations. The preset growth uniformity is the average value of the growth uniformity of the silicon core rod when no growth abnormal areas appear on the silicon core rod under the same deposition conditions within a number of second preset durations. The same deposition conditions include, but are not limited to, "the same silicon core rod growth stage, the same silicon core rod growth data, and the same silicon core rod intake data", but the above values are not limited to this, and those skilled in the art can also adjust the values according to actual needs.

[0032] The present invention can accurately judge the growth status of the current silicon core rod by comparing the surface temperature distribution uniformity of the silicon core rod within the first preset time period and the growth uniformity of the silicon core rod within the second preset time period with the corresponding preset values respectively. When the condition of "the temperature distribution uniformity is greater than or equal to the preset distribution uniformity, or the growth uniformity is greater than or equal to the preset growth uniformity" is met, it is determined to obtain data on the growth abnormal area, which can quickly lock the local growth abnormal area and timely conduct targeted analysis and processing of local problems; when "the temperature distribution uniformity is less than the preset distribution uniformity and the growth uniformity is less than the preset growth uniformity", it is determined to obtain the overall growth rate data, which helps to grasp the overall growth trend of the silicon core rod from a macroscopic level, discover problems existing in the overall growth process, and avoid ignoring the overall growth abnormality due to local judgment errors. Through the above method, the accuracy of analyzing polysilicon growth parameters is improved, and then the precise regulation of gas entry is realized to obtain a silicon core rod with uniform growth.

[0033] Specifically, in step S2, the steps of determining the surface temperature distribution uniformity of the silicon core rod within the first preset time period include: Step S2101, select a plurality of cross-sections at equal intervals along the axial direction of the silicon core rod, and select a plurality of points at equal angles in the circumferential direction on each cross-section as temperature monitoring points; Step S2102, obtain the temperature data of each monitoring point collected in real time within the first preset time period, and record the temperature values of each point at each moment to form a temperature data set with a time series; Step S2103, calculate the average temperature on the surface of the silicon core rod within the first preset time period, and calculate the deviation between the temperature value of each monitoring point and the average temperature; Step S2104, calculate the standard deviation of the temperature deviations of all monitoring points to obtain the surface temperature distribution uniformity of the silicon core rod within the first preset time period.

[0034] The present invention can perform non-contact temperature measurement on the surface of the silicon core rod through an infrared thermometer, and measure its temperature by measuring the infrared radiation intensity emitted by the surface of the silicon core rod. For example, according to the temperature range that the silicon core rod may reach during the production process, select a suitable infrared thermometer. For example, the ST300 colorimetric infrared thermometer is suitable for high-temperature measurement in polysilicon production, and its temperature measurement range can cover the temperature range during the growth of the silicon core rod. Select a high-precision infrared thermometer, such as the MLX90640 infrared array sensor, whose own frame accuracy is ±1°C. In a complex environment such as a reduction furnace, an infrared thermometer that is not sensitive to window contamination, signal attenuation, etc. should be selected. For example, the ST300 colorimetric thermometer is basically not affected by the material emissivity and signal attenuation, and is not sensitive to slight contamination of the window.

[0035] In an embodiment of the present invention, if the length of the silicon core rod is 1 meter and the first preset duration is 60 minutes, 5 cross-sections (0.2 meters, 0.4 meters, 0.6 meters, 0.8 meters, 1.0 meters) are selected at equal intervals along the axial direction of the silicon core rod. On each cross-section, 6 points are selected at equal angles in the circumferential direction (one monitoring point every 60 degrees). On the 5 cross-sections of the silicon core rod, 6 temperature monitoring points are evenly arranged on each cross-section, for a total of 30 monitoring points. During the first preset duration (60 minutes), the temperature data of each monitoring point is collected in real time, and the temperature data is recorded every minute to form a temperature data set in a time series. For example, the temperature data of monitoring point 1 within 60 minutes is: T 1,1 ,T 1,2 ,…,T 1,60 . For each monitoring point, calculate its average temperature within 60 minutes, then calculate the average temperature of all monitoring points. For each monitoring point, calculate the deviation between its average temperature and the overall average temperature, and calculate the standard deviation of the temperature deviations of all monitoring points to obtain the surface temperature distribution uniformity of the silicon core rod within the first preset duration.

[0036] Specifically, in step S2, the steps of determining the growth uniformity of the silicon core rod within the second preset duration include: Step S2201: Select a plurality of cross-sections at equal intervals along the axial direction of the silicon core rod, and select a plurality of points at equal angles in the circumferential direction on each cross-section as growth uniformity monitoring points; Step S2202: Regularly measure the growth parameters of the silicon core rod at each monitoring point within the second preset duration, and record the growth data of each point at each moment to form a time series of growth data; Step S2203: Process the growth data of all monitoring points within the second preset duration to calculate the diameter change rate on the surface of the silicon core rod during this duration; Step S2204: Calculate the deviation between the diameter change rate of each monitoring point and the average diameter change rate; Step S2205: Calculate the standard deviation of the diameter change rate deviations of all monitoring points to obtain the growth uniformity of the silicon core rod within the second preset duration.

[0037] The present invention can capture images of the silicon core rod through a high-speed camera, and then use image processing technology to analyze the contour of the silicon core rod in the image, so as to calculate its diameter change rate. For example, select a camera and lens that can withstand high temperatures, or use a heat insulation protection device to protect an ordinary camera. For example, an industrial camera with a heat insulation cover can be used, or an optical glass lens that can withstand high temperatures can be used. Select a high-resolution black-and-white camera because a black-and-white camera is more sensitive to infrared light in a high-temperature environment and can better capture the contour of the silicon core rod. In a high-temperature environment, the image may be affected by thermal radiation and thermal disturbance, resulting in a decrease in image quality. The automatic color equalization (ACE) algorithm can be used to preprocess the image to enhance the image contrast and suppress background light and thermal fog. The image inverse filtering technology is used to eliminate the influence of thermal disturbance on the image. Through the inverse filtering restoration technology in the frequency domain, the image quality is improved. The collected image is processed by image processing software (such as OpenCV) to extract the contour information of the silicon core rod. The edge detection algorithm (such as the Canny algorithm) can be used to identify the edge of the silicon core rod, calculate the diameter change rate of the silicon core rod, and calculate the diameter change rate at each monitoring point by analyzing the image data at multiple time points.

[0038] In an embodiment of the present invention, if the length of the silicon core rod is 1 meter and the second preset time period is 2 hours, 5 cross-sections (0.2 meters, 0.4 meters, 0.6 meters, 0.8 meters, 1.0 meters) are selected at equal intervals along the axial direction of the silicon core rod. At each cross-section, 6 points are selected at equal angles in the circumferential direction (one monitoring point every 60 degrees). On the 5 cross-sections of the silicon core rod, 6 growth uniformity monitoring points are evenly arranged on each cross-section, with a total of 30 monitoring points. During the second preset time period, the growth parameters of the silicon core rod at each monitoring point are regularly measured (for example, measured once every 30 minutes), and the growth data of each point at each moment is recorded to form a time series of growth data. For example, the growth data of monitoring point 1 within 2 hours is: D 1,1 ,D 1,2 ,…,D 1,4 , for each monitoring point, calculate its diameter change rate within the second preset time period, and then calculate the average diameter change rate of all monitoring points. For each monitoring point, calculate the deviation between its diameter change rate and the average diameter change rate, and calculate the standard deviation of the diameter change rate deviations of all monitoring points to obtain the growth uniformity of the silicon core rod within the second preset time period.

[0039] Specifically, in step S3, when determining whether to perform spatial splicing on the growth abnormal region, it is determined whether to perform spatial splicing on the growth abnormal region according to whether there is an overlapping region in the growth abnormal region; When there is an overlapping region in the growth abnormal region, it is determined that the growth abnormal region needs to be spatially spliced; When there is no non - overlapping area in the growth abnormal area, it is determined that there is no need to perform spatial splicing on the growth abnormal area.

[0040] In the embodiment of the present invention, determining whether there is a non - overlapping area in the growth abnormal area includes establishing a three - dimensional coordinate system with the central axis 9 of the silicon core rod as the coordinate axis, determining the spatial coordinate positions of each growth abnormal area on the silicon core rod, including the starting point and ending point coordinates. For each growth abnormal area, determine its range in the circumferential direction and the axial direction. For example, the first growth abnormal area 7 may be between 0.2 meters and 0.4 meters in the axial direction and from 0 degrees to 120 degrees in the circumferential direction; the second growth abnormal area 8 may be between 0.4 meters and 0.6 meters in the axial direction and from 120 degrees to 240 degrees in the circumferential direction. Compare the coordinate ranges of different growth abnormal areas to determine whether there is an overlapping area. If two growth abnormal areas have an overlapping part in the circumferential direction or the axial direction, it is considered that there is an overlapping area. If two growth abnormal areas have no overlapping part in both the circumferential direction and the axial direction, it is considered that there is a non - overlapping area.

[0041] It can be understood that in the actual deposition process of the silicon core rod to which the method of the present invention is applied, there will be different numbers of abnormal growth areas. Here, only two growth abnormal areas are used as an example to describe whether there is a non - overlapping area in the growth abnormal area in the embodiment of the present invention, rather than indicating that there are only two abnormal growth areas in the actual deposition process of the silicon core rod.

[0042] By establishing a three - dimensional coordinate system with the central axis 9 of the silicon core rod as the coordinate axis, the present invention can accurately determine the spatial coordinate positions of each growth abnormal area on the silicon core rod, including the ranges in the axial direction and the circumferential direction, and accurately obtain the specific distribution of the growth abnormal areas on the silicon core rod. When there is a non - overlapping area, a spatial splicing operation is performed to integrate the scattered growth abnormal areas into a continuous area, avoiding repeated analysis and processing caused by the dispersion of the growth abnormal areas, greatly improving the processing efficiency of the growth abnormal areas, reducing the labor and time costs. By judging whether there is a non - overlapping area in the growth abnormal area and deciding whether to perform spatial splicing, it helps to reasonably allocate production resources. For the case where there is no non - overlapping area, there is no need to perform splicing operations, and resources can be concentrated on targeted processing of existing growth abnormal areas; for the case where there is a non - overlapping area that needs to be spliced, after splicing, the overall scale and shape of the growth abnormal area can be more clearly understood, so as to more scientifically plan and allocate resources. Through the above - mentioned method, the accuracy of analyzing the growth parameters of polysilicon is improved, and then the precise control of gas entry is realized to obtain a silicon core rod with uniform growth.

[0043] Specifically, in step S3, the steps of performing spatial splicing on the growth abnormal area include: Step S3301, establish a three - dimensional coordinate system with the central axis 9 of the silicon core rod as the coordinate axis; Step S3302: Determine the boundary point coordinates of each growth anomaly region and its range parameters in the circumferential direction and the axial direction through measurement or calculation. Step S3303: Perform boundary matching based on the boundary point coordinates and range parameters of each growth anomaly region to identify the connection relationship between adjacent growth anomaly regions. Step S3304: Based on the boundary point coordinates and connection relationship of each growth anomaly region, splice the growth anomaly regions in space to form a continuous region.

[0044] In the embodiment of the present invention, the central axis 9 of the silicon core rod is used as the Z-axis, the center of the bottom surface of the silicon core rod is the origin O, the two mutually perpendicular horizontal directions are the X-axis and the Y-axis respectively, and the unit length is set to 1 millimeter. Growth anomaly region A: Axial range: The Z coordinate ranges from 100 mm to 150 mm. Circumferential range: Starting from the positive X-axis direction as the initial side, rotating clockwise by 30° to 90°. Boundary point coordinates: At Z = 100 mm, the point coordinates corresponding to 30° in the circumferential direction are (86.6, 50, 100), and the point coordinates corresponding to 90° are (0, 100, 100); at Z = 150 mm, the corresponding boundary point coordinates are (86.6, 50, 150) and (0, 100, 150). Growth anomaly region B: Axial range: The Z coordinate ranges from 140 mm to 190 mm. Circumferential range: Starting from the positive X-axis direction as the initial side, rotating clockwise by 80° to 140°. Boundary point coordinates: At Z = 140 mm, the point coordinates corresponding to 80° in the circumferential direction are (17.4, 98.5, 140), and the point coordinates corresponding to 140° are (-76.6, 64.3, 140); at Z = 190 mm, the corresponding boundary point coordinates are (17.4, 98.5, 190) and (-76.6, 64.3, 190). Growth anomaly region C: Axial range: The Z coordinate ranges from 180 mm to 230 mm. Circumferential range: Starting from the positive X-axis direction as the initial side, rotating clockwise by 130° to 190°. Boundary point coordinates: At Z = 180 mm, the point coordinates corresponding to 130° in the circumferential direction are (-64.3, 76.6, 180), and the point coordinates corresponding to 190° are (-98.5, -17.4, 180); at Z = 230 mm, the corresponding boundary point coordinates are (-64.3, 76.6, 230) and (-98.5, -17.4, 230). Connection relationship between abnormal growth region A and abnormal growth region B: The axial end point Z = 150 mm of abnormal growth region A overlaps with the axial starting point Z = 140 mm of abnormal growth region B (from 140 mm to 150 mm). The circumferential range of abnormal growth region A is from 30° to 90°, and the circumferential range of abnormal growth region B is from 80° to 140°. The two overlap from 80° to 90°. It can be determined that abnormal growth region A and abnormal growth region B overlap axially and partially overlap circumferentially, and there is an adjacent connection relationship; Connection relationship between abnormal growth region B and abnormal growth region C: The axial end point Z = 190 mm of abnormal growth region B overlaps with the axial starting point Z = 180 mm of abnormal growth region C (from 180 mm to 190 mm). The circumferential range of abnormal growth region B is from 80° to 140°, and the circumferential range of abnormal growth region C is from 130° to 190°. The two overlap from 130° to 140°. It can be determined that abnormal growth region B and abnormal growth region C overlap axially and partially overlap circumferentially, and there is an adjacent connection relationship; Connection relationship between abnormal growth region A and abnormal growth region C: The axial end point Z = 150 mm of abnormal growth region A does not overlap with the axial starting point Z = 180 mm of abnormal growth region C. The circumferential range of abnormal growth region A is from 30° to 90°, and the circumferential range of abnormal growth region C is from 130° to 190°. The two do not overlap. It can be determined that there is no adjacent connection relationship between abnormal growth region A and abnormal growth region C. After integrating the axial ranges of the three regions, it is from 100 mm to 230 mm. Circumferential range integration: After integrating the circumferential ranges of the three regions, it is from 30° to 190°; The spliced continuous region: Axial range: The Z coordinate is from 100 mm to 230 mm. Circumferential range: Starting from the positive X-axis direction as the starting side, rotate clockwise from 30° to 190°. This continuous region includes all parts of abnormal growth region A, abnormal growth region B, and abnormal growth region C, and through boundary matching and connection relationship recognition, they are spliced together.

[0045] Specifically, in step S4, when it is determined to control the intake air by the local control method or the overall control method, it is determined to control the intake air by the local control method or the overall control method according to the coverage range of the abnormal growth region with non-overlapping regions and the abnormal growth region after spatial splicing, as well as the comparison result between the overall growth rate of the silicon core rod and the preset overall growth rate; When the abnormal growth region with non-overlapping regions and the abnormal growth region after spatial splicing do not cover the entire circumference of the silicon core rod and the overall growth rate of the silicon core rod is greater than or equal to the preset overall growth rate, it is determined to control the intake air by the local control method; When any one of the growth abnormal regions with non-overlapping regions and the growth abnormal regions after spatial splicing covers the entire circumference of the silicon core rod or the overall growth rate of the silicon core rod is less than the preset overall growth rate, it is determined to control the intake air by the overall control method.

[0046] In the embodiment of the present invention, the preset overall growth rate is the average value of the overall growth rates of the silicon core rod under several identical deposition conditions. The judgment that neither the growth abnormal region with non-overlapping regions nor the growth abnormal region after spatial splicing covers the entire circumference of the silicon core rod includes that the circumferential direction of the growth abnormal region does not reach 360 degrees, but the above value is not limited to this, and those skilled in the art can also adjust this value according to actual needs.

[0047] The present invention can accurately judge the type and degree of the growth abnormality of the silicon core rod by comprehensively considering the coverage range of the growth abnormal region and the overall growth rate. When neither the non-overlapping region nor the growth abnormal region after splicing covers the entire circumference of the silicon core rod and the overall growth rate meets the standard, the local control method is adopted, which can accurately focus on the local growth abnormal region, avoid unnecessary interference to the normal growth region, and reduce the waste of energy and raw materials; when the growth abnormal region covers one week or the overall growth rate is insufficient, the overall control method is adopted in time to make adjustments from a macroscopic level to ensure the consistency of the growth environment of the entire silicon core rod, effectively solve the global growth problem, and improve the matching degree of the control strategy and the actual abnormal scenario. This method avoids the "one-size-fits-all" control method, flexibly selects local or overall control according to the actual situation. When there is a local abnormality and the overall growth is good, the local control only adjusts the intake air volume of the intake device corresponding to the growth abnormal region, without large-scale modification of the entire intake system, reducing the equipment adjustment time and energy consumption, and improving the production efficiency; in the case of overall abnormality, the overall control can quickly adjust the global intake air conditions to make the growth of the silicon core rod return to normal as soon as possible, shorten the abnormal handling time, and avoid the spread of the abnormality caused by untimely local control, thereby improving the resource utilization efficiency and reducing the production cost. Through the above method, the accuracy of the analysis of the polysilicon growth parameters is improved, and then the precise regulation of the gas inlet is realized to obtain a silicon core rod with uniform growth.

[0048] Specifically, in step S5, when it is determined to control the intake air by the local control method, the intake air volume or intake air angle of the intake device corresponding to the local growth abnormal region is determined according to whether there are conflict abnormal characteristics in the local growth abnormal region; When there are conflict abnormal characteristics in the local growth abnormal region, it is determined to adjust the intake air angle of the intake device corresponding to the local growth abnormal region; When there are no conflict abnormal characteristics in the local growth abnormal region, it is determined to adjust the intake air volume of the intake device corresponding to the local growth abnormal region.

[0049] In the embodiments of the present invention, determining whether there are conflicting abnormal features in the locally growing abnormal area includes the occurrence of conflicting growth conditions within the local area. For example, in the same area, the growth rate at some positions is greater than the maximum value of the growth rate in the non-growing abnormal area, while the growth rate at other positions is less than the minimum value of the growth rate in the non-growing abnormal area; the temperature at some positions in the same area is greater than the maximum value of the temperature in the non-growing abnormal area, while the temperature at other positions is less than the minimum value of the temperature in the non-growing abnormal area; the gas flow rate at some positions in the same area is less than the minimum value of the gas flow rate in the non-growing abnormal area, while the gas flow rate at other positions is greater than the maximum value of the gas flow rate in the non-growing abnormal area. Adjusting the intake angle of the intake device corresponding to the locally growing abnormal area includes adjusting the intake angle of the intake device to a direction tending to the weak abnormal features. The weak abnormal features include, but are not limited to, "the growth rate is less than the minimum value of the growth rate in the non-growing abnormal area, the temperature is less than the minimum value of the temperature in the non-growing abnormal area, and the gas flow rate is less than the minimum value of the gas flow rate in the non-growing abnormal area". The adjustment amount of the intake angle can be calculated by establishing a mathematical model and comprehensively considering the above parameters. For example, a adjustment coefficient is set, and this coefficient is proportional to the degree of difference of the abnormal features and the size of the growing abnormal area, and inversely proportional to the stability of the abnormal features. Through experiments or simulations, the specific values of the adjustment coefficient in different situations are determined, so as to calculate the adjustment amount of the intake angle.

[0050] In an embodiment of the present invention, during the polysilicon deposition process, real-time monitoring is performed on a certain silicon core rod. The surface temperature data, growth data of the silicon core rod, and the intake air data of the intake air device are obtained through the system. The first preset duration is set to 30 minutes, and the second preset duration is set to 60 minutes. After calculation, it is found that there are conflict abnormal characteristics in a local area of the silicon core rod with an axial length of 20 - 30 cm and a circumferential angle of 60° - 120°. It is necessary to adjust the intake air angle of the corresponding intake air device in this area. The maximum growth rate in the non-growth abnormal area is 0.5 mm / h. In this local growth abnormal area, the growth rate at some positions reaches 0.7 mm / h, while the growth rate at some other positions is only 0.2 mm / h. Taking the growth rate less than the minimum value of 0.2 mm / h as the analysis object, the difference between it and the minimum value of the non-growth abnormal area (assuming the minimum value of the non-growth abnormal area is 0.3 mm / h) is 0.1 mm / h; the maximum temperature in the non-growth abnormal area is 1050 °C, and the minimum value is 1000 °C. In this local growth abnormal area, the temperature at some positions is 1100 °C, and the temperature at some positions is 950 °C. Taking the temperature less than the minimum value of 950 °C as the analysis object, the difference between it and the minimum value of the non-growth abnormal area is 50 °C; the maximum gas flow rate in the non-growth abnormal area is 15 L / min, and the minimum value is 10 L / min. In this local growth abnormal area, the gas flow rate at some positions is 8 L / min, and the gas flow rate at some positions is 18 L / min. Taking the gas flow rate less than the minimum value of 8 L / min as the analysis object, the difference between it and the minimum value of the non-growth abnormal area is 2 L / min; weights are assigned to each parameter. Assuming the weight of the growth rate is 0.4, the weight of the temperature is 0.3, and the weight of the gas flow rate is 0.3; the difference degree score of the abnormal characteristics is calculated to be 15.64 through weighted average. The axial length of this local growth abnormal area is 10 cm, and the circumferential angle range is 60°. According to a certain quantization standard (for example, quantifying 1 cm in the axial direction as 1 point and 1° in the circumferential angle as 0.1 point), the size score of the growth abnormal area is calculated to be 16. By observing the data within the past 2 hours, it is found that this conflict abnormal characteristic has been continuously present. The stability score is set to 0.2 (the scoring range is 0 - 1, and the lower the value, the higher the stability and the more serious the problem). The adjustment coefficient calculation formula is set as adjustment coefficient = k × ; where k is a constant determined through experiments or simulations; the adjustment amount of the intake air angle has a linear relationship with the adjustment coefficient, and each unit of the adjustment coefficient corresponds to an intake air angle adjustment of 0.5°. Then the finally calculated intake air angle adjustment amount is the product of the adjustment coefficient and 0.5.

[0051] In the embodiment of the present invention, adjusting the intake air flow rate of the intake device corresponding to the locally abnormally growing area includes: when there are no conflicting abnormal features in the locally abnormally growing area, it is necessary to determine whether the overall growth state of this area is too fast or too slow. If the overall growth rate is less than the average growth rate of the non-abnormally growing area, it indicates that the growth is too slow. At this time, the intake air flow rate of the intake device should be increased to provide more reaction gas for the growth of the silicon core rod to accelerate the growth rate; if the overall growth rate is greater than the average growth rate of the non-abnormally growing area, it means that the growth is too fast, then the intake air flow rate of the intake device should be reduced to reduce the supply of reaction gas, thereby slowing down the growth rate; calculate the flow rate adjustment amount according to the difference in growth rate between the locally abnormally growing area and the non-abnormally growing area, establish a mathematical model, for example, set that the flow rate adjustment amount has a linear relationship with the growth rate difference, and determine the proportional coefficient through a large number of experiments or simulations. Assume that through experiments, it is determined that for every 0.1 mm / h difference in growth rate, the corresponding intake air flow rate is adjusted by 1 L / min. If the average growth rate of the locally abnormally growing area is 0.3 mm / h lower than the average growth rate of the non-abnormally growing area, then the intake air flow rate needs to be increased by 3 L / min.

[0052] The present invention provides a precise decision-making basis for adjusting the intake device by clearly distinguishing whether there are conflicting abnormal features in the locally abnormally growing area. When there are conflicting abnormal features, adjusting the intake angle can target the conflicting growth conditions within the area and focus on improving the weak abnormal features, such as increasing the concentration of reaction gas at the place where the growth is too slow and increasing the heat transfer at the place where the temperature is too low, etc., to achieve targeted regulation of complex abnormal situations; when there are no conflicting abnormal features, adjust the intake air flow rate based on the comparison between the overall growth rate and the non-abnormally growing area, which can effectively solve the problem of overall growth being too slow or too fast. For the local area without conflicting abnormal features, accurately calculate the intake air flow rate adjustment amount according to the growth rate difference, avoid the situation of excessive or insufficient gas supply, reduce the unnecessary consumption of reaction gas while ensuring the growth quality of the silicon core rod, and reduce the production cost; for the area with conflicting abnormal features, adjusting the intake angle can more reasonably distribute the gas flow direction. Through the above method, the accuracy of analyzing the growth parameters of polysilicon is improved, and then the precise regulation of gas entry is realized to obtain a silicon core rod with uniform growth.

[0053] Specifically, in step S5, when it is determined to control the intake air by the overall control method, determine the distribution position or distribution spacing of the overall intake device according to the degree of consistency of the abnormal features in the overall growth area; When the degree of consistency of the abnormal features in the overall growth area is less than or equal to the preset degree of consistency, determine to adjust the distribution position of the overall intake device; When the degree of consistency of the abnormal features in the overall growth area is greater than the preset degree of consistency, determine to adjust the distribution spacing of the overall intake device.

[0054] In an embodiment of the present invention, when it is determined to control the intake air by the overall control method, if the overall growth rate of the silicon core rod is less than the preset overall growth rate, the total intake air flow rate is increased. A mathematical model can be established to calculate the increase in the total intake air flow rate according to the difference between the overall growth rate and the preset overall growth rate. For example, it is set that the adjustment amount of the total intake air flow rate has a linear relationship with the growth rate difference, and the proportional coefficient is determined through a large number of experiments or simulations, and then the total intake air flow rate is increased according to the proportional coefficient.

[0055] In an embodiment of the present invention, the degree of consistency of the abnormal characteristics of the overall growth region can be determined according to the following method. The overall growth region is divided into multiple small sub-regions. The division of the sub-regions needs to comprehensively consider factors such as the shape of the silicon core rod and the distribution of the intake air device. For example, it can be evenly divided into several small regions along the axial and circumferential directions of the silicon core rod. For each sub-region, the growth rate, temperature, and gas flow rate data are collected respectively. For each abnormal characteristic parameter (growth rate, temperature, gas flow rate), first calculate the average characteristic value of the overall growth region, and then calculate the deviation between the characteristic value of each sub-region and the average characteristic value. For example, the growth rate deviation of the sub-region is the growth rate of the sub-region minus the average growth rate of the overall growth region. According to actual production experience and experimental data, different weights are assigned to each abnormal characteristic parameter. For example, since the growth rate has a greater impact on the quality of the silicon core rod, a higher weight (such as 0.5) can be assigned; the temperature and gas flow rate are assigned weights of 0.3 and 0.2 respectively. Multiply the deviation of each abnormal characteristic of each sub-region by the corresponding weight, and then sum to obtain the comprehensive abnormal characteristic deviation of the sub-region. Calculate the standard deviation of the comprehensive abnormal characteristic deviations of all sub-regions to obtain the degree of consistency of the abnormal characteristics of the overall growth region.

[0056] In the embodiments of the present invention, the preset degree of consistency is the average value of the degrees of consistency of the abnormal characteristics of the overall growth region during intake under the overall control method under several identical deposition conditions. Adjusting the distribution position of the overall intake device includes, but is not limited to, moving the intake device to regions with low growth rate, low temperature, and insufficient gas flow to enhance the gas supply in these regions. According to the abnormal characteristics of the sub-regions, the distribution position of the intake device is readjusted to make the gas more evenly distributed on the surface of the silicon core rod. Adjusting the distribution spacing of the overall intake device includes increasing the distance between the intake devices if the growth rate and temperature are generally high, and decreasing the distance between the intake devices if the growth rate and temperature are generally low. The moving amount of the intake device can be determined according to the severity of the abnormal characteristics of the sub-regions. For example, if the growth rate is more than 10% lower than the average value, the moving distance can be set to 10 cm; if it is 5%-10% lower than the average value, the moving distance can be set to 5 cm. The adjustment amount of the distribution spacing can be determined according to the general levels of the growth rate and temperature. For example, if the growth rate is more than 10% higher than the average value, the spacing is increased by 5 cm; if it is more than 10% lower than the average value, the spacing is decreased by 5 cm. However, the above values are not limited to this, and those skilled in the art can also adjust the values according to actual needs.

[0057] By selecting the method of adjusting the intake device according to the degree of consistency of the abnormal characteristics of the overall growth region, the present invention can more accurately address the problems that occur during the overall growth process of the silicon core rod. When the degree of consistency of the abnormal characteristics is low, adjusting the distribution position can accurately direct the gas to the regions with poor growth; when the degree of consistency is high, adjusting the distribution spacing can optimize the overall gas distribution, enabling the reaction gas to more effectively participate in the deposition process of the silicon core rod, reducing the uneven growth situation, thereby increasing the growth rate of the silicon core rod, improving production efficiency, reducing the differences in growth rate, temperature, and gas flow among different parts of the silicon core rod, enhancing the overall growth uniformity of the silicon core rod, and reducing the internal stress and defects caused by uneven growth, thereby improving the quality and performance of the silicon core rod.

[0058] Please refer to Figure 5 as shown in Figure 5 which is a schematic structural diagram of a polysilicon deposition intake device for the polysilicon deposition intake device control method applied to the embodiments of the present invention based on the growth characteristics of the silicon core rod.

[0059] Specifically, a polysilicon deposition intake device applied to the polysilicon deposition intake device control method based on the growth characteristics of the silicon core rod includes: An intake pipe, which includes a closed end 1 located in the deposition furnace, an interface end 3 connected to the silane intake port, and an outer pipe 5 and an inner pipe 6. The outer pipe 5 is sleeved on the inner pipe 6. The inner pipe 6 is used for flowing silane gas, and a sealed cavity is formed between the outer pipe 5 and the inner pipe 6 for heat insulation. The exhaust holes 2 are evenly spaced along the extension direction of the intake pipe, and the opening direction is inclined downward at an angle of 30°-60° with respect to the vertical direction (the axis direction of the silicon core rod) for evenly distributing the gas; The connecting piece 4 is located at the interface end and is used to connect the intake pipe to the silane inlet.

[0060] So far, the technical solution of the present invention has been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. A control method for a polysilicon deposition intake device based on the growth characteristics of a silicon ingot, characterized in that, Including: Obtaining the surface temperature data of the silicon core rod, the growth data of the silicon core rod, and the intake air data of the intake device during the deposition process; Determining to obtain the growth abnormal area data of the silicon core rod and the overall growth rate data of the silicon core rod based on the uniformity degree of the surface temperature distribution of the silicon core rod within a first preset time period and / or the growth uniformity degree of the silicon core rod within a second preset time period; Determining whether to perform spatial splicing on the growth abnormal area based on whether there is an overlapping area in the growth abnormal area; Determining to control the intake air by a local control method or an overall control method based on the coverage range of the growth abnormal area with non-overlapping areas and the spliced growth abnormal area, and the comparison result between the overall growth rate of the silicon core rod and the preset overall growth rate; Determining to adjust the intake air flow or intake air angle of the intake device corresponding to the local growth abnormal area based on whether there are conflict abnormal features in the local growth abnormal area, or determining to adjust the distribution position or distribution spacing of the overall intake device based on the consistency degree of the abnormal features of the overall growth area.

2. The control method of the polysilicon deposition intake device based on the growth characteristics of a silicon ingot rod according to claim 1, characterized in that, Determining to obtain the growth abnormal area data of the silicon core rod or obtain the overall growth rate data of the silicon core rod includes: If the uniformity degree of the surface temperature distribution of the silicon core rod within a first preset time period is greater than or equal to the preset distribution uniformity degree or the growth uniformity degree of the silicon core rod within a second preset time period is greater than or equal to the preset growth uniformity degree, determining to obtain the growth abnormal area data of the silicon core rod; If the uniformity degree of the surface temperature distribution of the silicon core rod within a first preset time period is less than the preset distribution uniformity degree and the growth uniformity degree of the silicon core rod within a second preset time period is less than the preset growth uniformity degree, determining to obtain the overall growth rate data of the silicon core rod.

3. The control method of the polysilicon deposition intake device based on the growth characteristics of the silicon ingot according to claim 2, wherein, Calculating the uniformity degree of the surface temperature distribution of the silicon core rod within a first preset time period includes: Selecting a number of cross-sections at equal intervals along the axial direction of the silicon core rod, and selecting a plurality of points at equal angles in the circumferential direction on each cross-section as temperature monitoring points; Obtaining the temperature data of each monitoring point collected in real time within a first preset time period, and recording the temperature values of each point at each moment to form a time series temperature data set; Calculating the average temperature on the surface of the silicon core rod within a first preset time period, and calculating the deviation between the temperature value of each monitoring point and the average temperature; Calculating the standard deviation of the temperature deviations of all monitoring points to obtain the uniformity degree of the surface temperature distribution of the silicon core rod within a first preset time period.

4. The control method of the polysilicon deposition intake device based on the growth characteristics of the silicon core rod according to claim 2, characterized in that, Calculating the growth uniformity degree of the silicon core rod within a second preset time period includes: Selecting a number of cross-sections at equal intervals along the axial direction of the silicon core rod, and selecting a plurality of points at equal angles in the circumferential direction on each cross-section as growth uniformity monitoring points; Regularly measuring the growth parameters of the silicon core rod at each monitoring point within a second preset time period, and recording the growth data of each point at each moment to form a time series of growth data; Processing the growth data of all monitoring points within a second preset time period, and calculating the diameter change rate on the surface of the silicon core rod within this time period; Calculating the deviation between the diameter change rate of each monitoring point and the average diameter change rate; Calculating the standard deviation of the diameter change rate deviations of all monitoring points to obtain the growth uniformity degree of the silicon core rod within a second preset time period.

5. The control method of the polysilicon deposition intake device based on the growth characteristics of the silicon ingot rod according to claim 4, characterized in that, Determining whether to perform spatial splicing on the growth abnormal area includes: If there is an unoverlapped area in the growth abnormal area, it is determined that the growth abnormal area needs to be spatially spliced; If there is no unoverlapped area in the growth abnormal area, it is determined that the growth abnormal area does not need to be spatially spliced.

6. The control method for the polysilicon deposition intake device based on the growth characteristics of a silicon ingot, as claimed in claim 5, wherein Spatially splicing the growth abnormal area includes: Establish a three-dimensional coordinate system with the central axis of the silicon core rod as the coordinate axis; Determine the boundary point coordinates of each growth abnormal area and its range parameters in the circumferential and axial directions through measurement or calculation; Based on the boundary point coordinates and range parameters of each growth abnormal area, perform boundary matching to identify the connection relationship between adjacent growth abnormal areas; Based on the boundary point coordinates and connection relationship of each growth abnormal area, splice the growth abnormal areas spatially to form a continuous area.

7. The control method of the polysilicon deposition intake device based on the growth characteristics of the silicon ingot according to claim 6, characterized in that, Determining to control the intake air by a local control method or an overall control method includes: If the growth abnormal areas with unoverlapped areas and the growth abnormal areas after spatial splicing do not cover the entire circumference of the silicon core rod and the overall growth rate of the silicon core rod is greater than or equal to the preset overall growth rate, it is determined to control the intake air by a local control method; If any of the growth abnormal areas with unoverlapped areas and the growth abnormal areas after spatial splicing covers the entire circumference of the silicon core rod or the overall growth rate of the silicon core rod is less than the preset overall growth rate, it is determined to control the intake air by an overall control method.

8. The control method of the polysilicon deposition intake device based on the growth characteristics of a silicon ingot, as claimed in claim 7, wherein Determining to adjust the intake air flow rate or intake air angle of the intake device corresponding to the local growth abnormal area includes: If there are conflict abnormal features in the local growth abnormal area, it is determined to adjust the intake air angle of the intake device corresponding to the local growth abnormal area; If there are no conflict abnormal features in the local growth abnormal area, it is determined to adjust the intake air flow rate of the intake device corresponding to the local growth abnormal area.

9. The control method of the polysilicon deposition intake device based on the growth characteristics of a silicon ingot according to claim 8, characterized in that Determining to adjust the distribution position or distribution spacing of the overall intake device includes: If the degree of consistency of the abnormal features in the overall growth area is less than or equal to the preset degree of consistency, it is determined to adjust the distribution position of the overall intake device; If the degree of consistency of the abnormal features in the overall growth area is greater than the preset degree of consistency, it is determined to adjust the distribution spacing of the overall intake device.

10. A polysilicon deposition intake device for the control method of the polysilicon deposition intake device based on the growth characteristics of a silicon core rod according to any one of claims 1-9, characterized in that, Includes: An intake pipe, which includes a closed end located in the deposition furnace, an interface end connected to the silane intake port, and an outer pipe and an inner pipe. The outer pipe is sleeved on the inner pipe. The inner pipe is used for flowing silane gas, and a sealed cavity is formed between the outer pipe and the inner pipe for heat insulation; Exhaust holes, which are evenly spaced along the extending direction of the intake pipe, and the opening direction is inclined downward at 30° - 60° with respect to the axis direction of the silicon core rod for evenly distributing gas; A connector, which is located at the interface end for connecting the intake pipe to the silane intake port.

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