Manufacturing method of silicon single crystal rod and silicon wafer

Abstract

The invention relates to a manufacturing method of a silicon single crystal rod and a silicon wafer. The method comprises the following steps: acquiring relevant parameters of a silicon single crystal rod, acquiring a target segregation model corresponding to the silicon single crystal rod according to the relevant parameters of the silicon single crystal rod, generating a target cutting instruction according to the relevant parameters of the silicon single crystal rod and the target segregation model, and cutting the silicon single crystal rod according to the target cutting instruction; the target segregation model represents the mapping relation between the impurity concentration and the crystal generation length of the single crystal silicon rod. According to the embodiment of the invention, the target cutting instruction is generated through the obtained related parameters of the single crystal silicon rod and the target segregation model, the unqualified part of the tail resistor of the single crystal silicon rod is automatically cut off based on the target cutting instruction, a traditional artificial experience judgment and manual cutting mode is replaced, the cutting efficiency and the cutting precision are improved, and the production cost is reduced. The silicon material loss in the manufacturing process of the monocrystalline silicon rod is reduced, the qualified rate and the resource utilization rate of the monocrystalline silicon rod are improved, and intelligent upgrading of monocrystalline silicon manufacturing is promoted.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor technology, and in particular to a single crystal silicon rod manufacturing method and a silicon wafer. BACKGROUND

[0002] Tail resistance back cutting refers to a process of cutting and removing the tail of a single crystal silicon rod according to a measured resistance value after the single crystal silicon rod is drawn. If the single crystal silicon rod with uneven resistance is directly cut into slices, the resistance of the produced silicon wafer is chaotic, resulting in a very low yield of the whole single crystal silicon rod and high cost. Therefore, tail resistance back cutting is an indispensable bridge between a Czochralski silicon rod and a qualified silicon wafer, and is a key and necessary process for ensuring product quality and controlling production cost in the modern semiconductor industry.

[0003] At present, the tail resistance back cutting of a Czochralski single crystal silicon rod relies on manual detection, but this method needs to measure a single single crystal silicon rod multiple times, and has the problem of high labor cost. SUMMARY

[0004] Therefore, it is necessary to provide a single crystal silicon rod manufacturing method and a silicon wafer capable of reducing labor cost in view of the above technical problems.

[0005] In a first aspect, the present application provides a single crystal silicon rod manufacturing method, comprising:

[0006] obtaining related parameters of a single crystal silicon rod;

[0007] obtaining a target segregation model corresponding to the single crystal silicon rod according to the related parameters of the single crystal silicon rod; the target segregation model represents a mapping relationship between impurity concentration and crystal generation length of the single crystal silicon rod;

[0008] generating a target cutting instruction according to the related parameters of the single crystal silicon rod and the target segregation model;

[0009] cutting the single crystal silicon rod according to the target cutting instruction.

[0010] In one embodiment, the related parameters include a target tail resistance of the single crystal silicon rod and an actual growth length of the single crystal silicon rod; and the generating of the target cutting instruction according to the related parameters of the single crystal silicon rod and the target segregation model comprises:

[0011] determining a target growth length of the single crystal silicon according to the target tail resistance of the single crystal silicon rod and the target segregation model;

[0012] generating the target cutting instruction according to the actual growth length of the single crystal silicon rod and the target growth length.

[0013] In one embodiment, the determining of the target growth length of the single crystal silicon according to the target tail resistance of the single crystal silicon rod and the target segregation model comprises:

[0014] The solidification percentage of the single-crystal silicon rod is determined based on the target segregation model and the target tail resistance of the single-crystal silicon rod.

[0015] Based on the solidification percentage of the single-crystal silicon rod and the initial weight of the silicon melt, determine the weight of the solidified silicon melt when the single-crystal silicon rod reaches the target tail resistance.

[0016] The target growth length corresponding to the weight of the silicon melt is determined based on the conversion factor between the weight and length of the silicon melt.

[0017] In one embodiment, the method for fabricating a single-crystal silicon rod further includes:

[0018] The length conversion factor of the single-crystal silicon rod is determined based on its density and radius.

[0019] In one embodiment, cutting a single-crystal silicon rod according to a target cutting instruction includes:

[0020] The target cutting point is determined based on the actual growth length and target growth length of the monocrystalline silicon rod;

[0021] Generate target cutting instructions based on the target cutting points;

[0022] During the process of cutting a monocrystalline silicon rod using the target cutting command, the first tail detection resistor of the monocrystalline silicon rod is obtained, and the target cutting command is regenerated based on the first tail detection resistor.

[0023] Cut the single-crystal silicon rod according to the regenerated target cutting instructions.

[0024] In one embodiment, the target cutting command includes a reverse cutting length value and cutting parameters of the cutting device.

[0025] In one embodiment, the reverse shear length value ranges from 0 mm to 500 mm.

[0026] In one embodiment, the relevant parameters include the head resistance of the monocrystalline silicon rod; based on the relevant parameters of the monocrystalline silicon rod, the target segregation model corresponding to the monocrystalline silicon rod is obtained, including:

[0027] The head impurity concentration of the monocrystalline silicon rod is determined based on the head resistance of the monocrystalline silicon rod.

[0028] The initial concentration of silicon melt in the monocrystalline silicon rod is determined based on the impurity concentration at the head of the monocrystalline silicon rod and the segregation coefficient corresponding to the monocrystalline silicon rod.

[0029] The target segregation model is obtained based on the initial concentration of silicon melt and the segregation coefficient.

[0030] In one embodiment, the method for fabricating a single-crystal silicon rod further includes:

[0031] obtaining a second tail detection resistance of the cut single crystal silicon rod and a detection impurity concentration corresponding to the second tail detection resistance;

[0032] optimizing a segregation coefficient in a target segregation model according to the second tail detection resistance, the detection impurity concentration corresponding to the second tail detection resistance, the target tail resistance and the impurity concentration corresponding to the target tail resistance.

[0033] In a second aspect, the application further provides a silicon wafer, which is prepared by slicing a single crystal silicon rod prepared by the method of any one of the first aspect.

[0034] The method of manufacturing a single crystal silicon rod and the silicon wafer described above obtain the related parameters of the single crystal silicon rod, obtain a target segregation model corresponding to the single crystal silicon rod according to the related parameters of the single crystal silicon rod, generate a target cutting instruction according to the related parameters of the single crystal silicon rod and the target segregation model, and cut the single crystal silicon rod according to the target cutting instruction. The target segregation model represents the mapping relationship between the impurity concentration and the crystal generation length of the single crystal silicon rod. The embodiments of the application generate the target cutting instruction by obtaining the related parameters of the single crystal silicon rod and the target segregation model, and automatically cut off the unqualified part of the tail resistance of the single crystal silicon rod based on the target cutting instruction, thereby replacing the traditional manual experience judgment and manual cutting method, improving the cutting efficiency and cutting precision, reducing the loss of silicon material in the manufacturing of the single crystal silicon rod, improving the yield and resource utilization of the single crystal silicon rod, and promoting the intelligent upgrading of the single crystal silicon manufacturing. BRIEF DESCRIPTION OF DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the application or the related art, the following will briefly introduce the drawings needed to be used in the description of the embodiments of the application or the related art. Obviously, the drawings in the following description are only some embodiments of the application, and for those skilled in the art, other related drawings can also be obtained without creative labor.

[0036] Figure 1 It is a flowchart of a manufacturing method of a single crystal silicon rod in a conventional technology;

[0037] Figure 2 It is a flowchart of a manufacturing method of a single crystal silicon rod in another conventional technology;

[0038] Figure 3 It is a flowchart of a manufacturing method of a single crystal silicon rod in an embodiment;

[0039] Figure 4 It is a flowchart of the generation of a target cutting instruction in an embodiment;

[0040] Figure 5A flowchart of a method for determining a target growth length in an embodiment;

[0041] Figure 6 A flowchart of a method for manufacturing a single crystal silicon rod in another embodiment;

[0042] Figure 7 A block diagram of a manufacturing device for a single crystal silicon rod in an embodiment;

[0043] Figure 8 An internal structure diagram of a computer device in an embodiment. DETAILED DESCRIPTION

[0044] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and do not limit the present application.

[0045] It should be noted that the terms "first", "second", etc. used in the present application can be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish the first element from the second element. The terms "include" and "have" used in the present application and any variations thereof are intended to cover non-exclusive inclusion. The term "multiple" used in the present application refers to two or more. The term "and / or" used in the present application refers to one of the options or any combination of multiple options.

[0046] Currently, there are mainly two technical paths for the back cutting processing of the unqualified part of the tail resistance of the Czochralski single crystal silicon rod: manual four-probe detection method: as shown in Figure 1 , the resistance is detected from the tail of the single crystal silicon rod to the front by manual four-probe, until the cutting position of the target tail resistance is found. For example, the operator needs to move the four-probe along the axial direction of the single crystal silicon rod, and measure the resistance at a certain distance (such as 10 cm) each time, until the qualified area is detected. The manual four-probe detection method needs to measure the single single crystal silicon rod multiple times, and the labor cost is high. Experienced value automatic back cutting method: as shown in Figure 2 , the back cutting length standard (such as fixed cutting 200 mm) is preset based on historical data or process model, and the cutting is directly performed by automatic equipment. For example, a cutting machine bed controlled by a programmable logic controller (PLC) is used to perform the cutting.

[0047] In an exemplary embodiment, as shown in Figure 3 , a method for manufacturing a single crystal silicon rod is provided, comprising the following S301 to S304. Wherein:

[0048] S301, obtain related parameters of the single crystal silicon rod.

[0049] The related parameters of the single crystal silicon rod include a target tail resistance of the single crystal silicon rod, an actual growth length of the single crystal silicon rod, a head resistance of the single crystal silicon rod, an initial silicon melt weight at a seeding start stage, and the like.

[0050] Optionally, the single crystal silicon rod can be an N-type phosphorus-doped single crystal silicon rod of various sizes, or a P-type boron-doped single crystal silicon rod of various sizes.

[0051] In the embodiments of the present application, the industrial control computer obtains detection data obtained by measuring the single crystal silicon rod by each detection device in real time. For example, a high-precision resistance tester is used to detect the head resistance of the single crystal silicon rod in real time, so as to ensure that the measurement error is within ±0.1Ω; a weighing sensor is used to accurately measure the initial silicon melt weight at the seeding start stage, and the accuracy reaches ±0.1g; a laser range finder is used to measure the actual generation length of the single crystal silicon rod, and the error is controlled within ±0.1mm. These detection data are transmitted to the industrial control computer in real time through a data acquisition card.

[0052] S302, obtain a target segregation model corresponding to the single crystal silicon rod according to the related parameters of the single crystal silicon rod; the target segregation model represents a mapping relationship between the impurity concentration of the single crystal silicon rod and the crystal generation length.

[0053] In the embodiments of the present application, the head impurity concentration of the single crystal silicon rod can be determined according to the head resistance of the single crystal silicon rod, the initial silicon melt concentration of the single crystal silicon rod can be determined according to the head impurity concentration of the single crystal silicon rod and the segregation coefficient corresponding to the single crystal silicon rod, and the target segregation model can be obtained further according to the initial silicon melt concentration and the segregation coefficient.

[0054] In one possible implementation, a mapping relationship among the head resistance of the single crystal silicon rod, the segregation coefficient corresponding to the single crystal silicon rod, and the segregation model can also be established in advance, and the target segregation model matched with the head resistance of the single crystal silicon rod can be determined based on the mapping relationship after the head resistance of the single crystal silicon rod is obtained.

[0055] S303, generate a target cutting instruction according to the related parameters of the single crystal silicon rod and the target segregation model.

[0056] The target cutting instruction includes a back-cut length value and a cutting parameter of a cutting device; the range of the back-cut length value is 0mm-500mm, an abnormal back-cut length value can be automatically uploaded to a manufacturing execution system (Manufacturing Execution System, MES), the silicon melt doping record and the thermal field parameter are associated, and a process parameter abnormality alarm is automatically triggered. The cutting parameter can be a moving path speed of the cutting device, a cutting depth, a cutting angle, an impact force, and the like.

[0057] In the embodiment of the present application, the target growth length of the single crystal silicon can be determined according to the target tail resistance and the target segregation model of the single crystal silicon rod, the back cutting length value can be determined according to the actual growth length and the target growth length of the single crystal silicon rod, the industrial control computer transmits the calculated back cutting length value to the controller of the automatic cutting system, and the controller determines the cutting parameters of the cutting equipment based on the back cutting length value to generate the target cutting instruction.

[0058] S304, cutting the single crystal silicon rod according to the target cutting instruction.

[0059] In the embodiment of the present application, the controller controls the movement path and cutting depth of the cutting equipment according to the target cutting instruction to realize the automatic back cutting of the unqualified part of the tail resistance of the single crystal silicon rod.

[0060] In the above method for manufacturing the single crystal silicon rod, the related parameters of the single crystal silicon rod are obtained, the target segregation model corresponding to the single crystal silicon rod is obtained according to the related parameters of the single crystal silicon rod, the target cutting instruction is generated according to the related parameters of the single crystal silicon rod and the target segregation model, and the single crystal silicon rod is cut according to the target cutting instruction; the target segregation model represents the mapping relationship between the impurity concentration and the crystal growth length of the single crystal silicon rod. In the embodiment of the present application, the target cutting instruction is generated according to the obtained related parameters of the single crystal silicon rod and the target segregation model, and the automatic cutting of the unqualified part of the tail resistance of the single crystal silicon rod is realized based on the target cutting instruction, which replaces the traditional manual experience judgment and manual cutting mode, improves the cutting efficiency and cutting precision, reduces the silicon material loss in the manufacturing of the single crystal silicon rod, improves the qualification rate and resource utilization rate of the single crystal silicon rod, and promotes the intelligent upgrading of the single crystal silicon manufacturing.

[0061] Figure 4 For a flowchart of generating a target cutting instruction in an embodiment, as shown in Figure 4 The embodiment of the present application relates to a possible implementation manner of how to generate a target cutting instruction according to the related parameters of a single crystal silicon rod and a target segregation model, and includes the following steps:

[0062] S401, determining the target growth length of the single crystal silicon according to the target tail resistance and the target segregation model of the single crystal silicon rod.

[0063] In the embodiment of the present application, the solidification percentage of the single crystal silicon rod can be determined according to the target segregation model and the target tail resistance of the single crystal silicon rod, and the silicon melt weight that has been solidified when the single crystal silicon rod reaches the target tail resistance can be determined according to the product of the solidification percentage of the single crystal silicon rod and the initial silicon melt weight, so as to determine the target growth length corresponding to the silicon melt weight according to the length conversion coefficient of the silicon melt weight.

[0064] In a possible implementation, the resistance distribution curve of the solidification percentage g=0 to g=0.99 can also be pre-calculated according to the target segregation model, the abscissa is the solidification percentage g, and the ordinate is the theoretical resistance. Since the crystal growth length is proportional to the solidification quality, and the solidification quality is proportional to the solidification percentage, the crystal growth length is also proportional to the solidification percentage (in the equal-diameter growth stage). The abscissa of the resistance distribution curve is replaced by the crystal growth length. In this way, a relationship curve of the theoretical resistance and the crystal growth length is obtained. The target growth length of the single crystal silicon is determined according to the target tail resistance of the single crystal silicon rod and the relationship curve of the theoretical resistance and the crystal growth length.

[0065] S402, generating a target cutting instruction according to the actual growth length and the target growth length of the single crystal silicon rod.

[0066] In the embodiment of the application, the actual growth length of the single crystal silicon rod is the length of the single crystal silicon rod that has been drawn at present. Therefore, the back-cut length value can be determined according to the difference between the actual growth length and the target growth length of the single crystal silicon rod, the cutting parameters of the cutting equipment are determined according to the back-cut length value, and thus the target cutting instruction is generated.

[0067] In the embodiment of the application, the target growth length of the single crystal silicon is determined according to the target tail resistance of the single crystal silicon rod and the target segregation model, the target cutting instruction is generated according to the actual growth length and the target growth length of the single crystal silicon rod, which lays a foundation for subsequent automatic back-cutting of the single crystal silicon rod based on the target cutting instruction, and improves the intelligence of the single crystal silicon rod manufacturing and the detection efficiency of the tail resistance of the single crystal silicon rod.

[0068] Figure 5 For a flowchart of the method for determining the target growth length in an embodiment, as shown in FIG. 1, the embodiment of the application relates to a possible implementation of how to determine the target growth length of the single crystal silicon according to the target tail resistance of the single crystal silicon rod and the target segregation model, which includes the following steps. Figure 5

[0069] S501, determining the solidification percentage of the single crystal silicon rod according to the target segregation model and the target tail resistance of the single crystal silicon rod.

[0070] In the embodiment of the application, the tail impurity concentration of the single crystal silicon rod can be determined according to the target tail resistance of the single crystal silicon rod, and the tail impurity concentration is substituted into the target segregation model to obtain the solidification percentage of the single crystal silicon rod.

[0071] S502, determining the solidified silicon melt weight of the single crystal silicon rod when the target tail resistance is reached according to the solidification percentage of the single crystal silicon rod and the initial silicon melt weight.

[0072] ​The initial silicon melt weight is related to the initial material state of the single crystal silicon rod.

[0073] In the embodiment of the present application, the solidification percentage represents the proportion of the solidified part to the initial silicon melt weight, and thus the solidified silicon melt weight of the single crystal silicon rod when reaching the target tail resistance can be obtained based on the solidification percentage and the initial silicon melt weight.

[0074] S503, determining the target growth length corresponding to the silicon melt weight according to the length conversion coefficient of the silicon melt weight.

[0075] The length conversion coefficient S of the single crystal silicon rod can be determined according to the density and radius of the single crystal silicon rod, and can be expressed as S = 1 / (p x p x (d / 2) 2 ), wherein p is the density of the single crystal silicon rod, and d is the diameter of the single crystal silicon rod.

[0076] The conversion coefficients of the weight and length of the single crystal silicon rod under different diameters are calculated and stored in the system database.

[0077] In the embodiment of the present application, the formula L = m x S = m / (p x p x (d / 2) 2 ), wherein L is the target growth length corresponding to the silicon melt weight, and m is the silicon melt weight.

[0078] In the embodiment of the present application, the solidification percentage of the single crystal silicon rod is determined according to the target segregation model and the target tail resistance of the single crystal silicon rod, the solidified silicon melt weight of the single crystal silicon rod when reaching the target tail resistance is determined according to the solidification percentage of the single crystal silicon rod and the initial silicon melt weight, and the target growth length corresponding to the silicon melt weight is determined according to the silicon melt weight and the length conversion coefficient.

[0079] In one embodiment, the single crystal silicon rod is cut according to the target cutting instruction, including the following steps:

[0080] The target cutting point is determined according to the actual growth length and the target growth length of the single crystal silicon rod, the target cutting instruction is generated according to the target cutting point, the first tail detection resistance of the single crystal silicon rod is obtained in the process of cutting the single crystal silicon rod by using the target cutting instruction, and the target cutting instruction is regenerated according to the first tail detection resistance, and the single crystal silicon rod is cut according to the regenerated target cutting instruction.

[0081] In the embodiment of the present application, the back-cut length value is determined according to the difference between the actual growth length and the target growth length of the single crystal silicon rod, the back-cut length value is taken as the target cutting point at the position corresponding to the single crystal silicon rod, and the initial cutting instruction is generated according to the target cutting point. The controller controls the cutting device to cut the single crystal silicon rod based on the initial cutting instruction. In the cutting process, the cutting angular velocity, cutting speed, etc. of the cutting device may cause the cutting surface of the single crystal silicon rod to be uneven or the cutting surface to have abnormalities. The four-probe resistance detection module and the optical positioning system can be integrated to perform high-precision scanning on the tail of the single crystal silicon rod, obtain the first tail detection resistance of the single crystal silicon rod, and identify the unqualified boundary in the cutting process in real time according to the first tail detection resistance, so as to adjust the cutting parameters of the cutting device, regenerate the target cutting instruction, and cut the single crystal silicon rod based on the regenerated target cutting instruction, thereby realizing the error of the back-cut length ≤ 3 mm.

[0082] Optionally, the cutting device can be a water jet driven by a servo motor.

[0083] In the embodiment of the present application, the target cutting point is determined according to the actual growth length and the target growth length of the single crystal silicon rod, the target cutting instruction is generated according to the target cutting point, the first tail detection resistance of the single crystal silicon rod is obtained in the process of cutting the single crystal silicon rod by using the target cutting instruction, and the target cutting instruction is regenerated according to the first tail detection resistance. The single crystal silicon rod is cut according to the regenerated target cutting instruction, so that the difference between the actual tail resistance after cutting and the target tail resistance is smaller, the cutting precision of the single crystal silicon rod is improved, the resistance real-time detection module, the segregation simulation calculation unit and the automatic cutting device are integrated to form a full-process unmanned operation.

[0084] In one embodiment, the target segregation model corresponding to the single crystal silicon rod is obtained according to the related parameters of the single crystal silicon rod, including: determining the head impurity concentration of the single crystal silicon rod according to the head resistance of the single crystal silicon rod; determining the initial concentration of the silicon melt of the single crystal silicon rod according to the head impurity concentration of the single crystal silicon rod and the segregation coefficient corresponding to the single crystal silicon rod; and obtaining the target segregation model according to the initial concentration of the silicon melt and the segregation coefficient.

[0085] In the embodiments of the present application, the head resistance of the single crystal silicon rod reflects the electrical property of the head of the single crystal silicon rod. According to the type of the dopant of the single crystal silicon rod, the standard Irvin curve (resistance-impurity concentration relationship curve) is consulted to determine the head impurity concentration corresponding to the head resistance. In the initial stage of crystal growth, the impurity concentration in the single crystal silicon satisfies the segregation relationship with the impurity concentration in the silicon melt. According to the ratio of the head impurity concentration of the single crystal silicon rod and the corresponding segregation coefficient of the single crystal silicon rod, the initial concentration of the silicon melt of the single crystal silicon rod is determined. Since in the process of crystal growth, as the crystal is continuously precipitated, the impurities in the silicon melt will gradually enrich, and the relationship between the impurity concentration in the solid phase and the crystal length can be described by the segregation model. Therefore, the initial concentration of the silicon melt and the segregation coefficient are brought into the normal solidification model to solve, and the target segregation model is obtained.

[0086] In the embodiments of the present application, the head resistance of the single crystal silicon rod reflects the electrical property of the head of the single crystal silicon rod. According to the type of the dopant of the single crystal silicon rod, the standard Irvin curve (resistance-impurity concentration relationship curve) is consulted to determine the head impurity concentration corresponding to the head resistance. In the initial stage of crystal growth, the impurity concentration in the single crystal silicon satisfies the segregation relationship with the impurity concentration in the silicon melt. According to the ratio of the head impurity concentration of the single crystal silicon rod and the corresponding segregation coefficient of the single crystal silicon rod, the initial concentration of the silicon melt of the single crystal silicon rod is determined. Since in the process of crystal growth, as the crystal is continuously precipitated, the impurities in the silicon melt will gradually enrich, and the relationship between the impurity concentration in the solid phase and the crystal length can be described by the segregation model. Therefore, the initial concentration of the silicon melt and the segregation coefficient are brought into the normal solidification model to solve, and the target segregation model is obtained.

[0087] In one embodiment, the method for manufacturing a single crystal silicon rod further comprises: obtaining a second tail detection resistance of the cut single crystal silicon rod and a detection impurity concentration corresponding to the second tail detection resistance; and optimizing the segregation coefficient in the target segregation model according to the second tail detection resistance, the detection impurity concentration corresponding to the second tail detection resistance, a target tail resistance, and a tail impurity concentration corresponding to the target tail resistance.

[0088] In the embodiments of the present application, the resistance difference between the second tail detection resistance and the target tail resistance is determined, and the impurity concentration difference between the detection impurity concentration corresponding to the second tail detection resistance and the tail impurity concentration is determined. The segregation coefficient in the target segregation model is optimized according to the resistance difference and the impurity concentration difference. The dynamic correction response time of the segregation coefficient is ≤1 second. A “detection-simulation-cut-verification” full-process closed-loop control system is established. The second tail detection resistance after actual cutting and the detection impurity concentration corresponding to the second tail detection resistance are fed back to the target segregation model. The segregation coefficient is iteratively optimized. Real-time process optimization is supported. The target segregation model can adapt to different process scenarios (such as P-type / N-type silicon rods and boron / phosphorus doping). It is ensured that the error between the calculation result of the target segregation model and the actual production data is within an acceptable range. This scheme integrates the segregation theory modeling and intelligent control technology, and provides an efficient and high-precision solution for the tail resistance quality control of the Czochralski single crystal silicon rod.

[0089] The initial silicon melt weight can also be introduced as a weight factor of the target segregation model, and by changing the initial silicon melt weight, the segregation parameters in the target segregation model are dynamically affected or targeted, thereby improving the adaptability under different process parameter scenarios (e.g., the initial silicon melt weight fluctuates ±20% and still can be stably output).

[0090] In order to better introduce the embodiments of the present application, as shown in Figure 6 the head resistance of the single crystal silicon rod is 0.66Ω·cm, the initial silicon melt weight is 600kg, the actual growth length is 2000mm, and the target tail resistance is 0.54Ω·cm. The diameter of the single crystal silicon rod is 274.6mm, and the density of the single crystal silicon rod is 2.329g / cm 3 .

[0091] According to the head resistance 0.66Ω·cm, the segregation model is calculated to determine the head impurity concentration of the single crystal silicon rod. According to the head impurity concentration of the single crystal silicon rod and the corresponding segregation coefficient of the single crystal silicon rod, the initial concentration of the silicon melt of the single crystal silicon rod is determined. According to the initial concentration of the silicon melt and the segregation coefficient, the target segregation model is obtained.

[0092] According to the target tail resistance 0.54Ω·cm and the target segregation model, the solidification percentage is calculated to be 30%. According to the solidification percentage 30% and the initial silicon melt weight 600kg, the solidified silicon melt weight of the single crystal silicon rod when reaching the target tail resistance is calculated to be 30%×600kg=180kg. The length conversion coefficient is calculated to be L=1 / ((2.329)×π×(0.2746 / 2) 2 ) = 7.25 by the density and diameter of the single crystal silicon rod. The target growth length corresponding to the solidified silicon melt weight 180kg is converted to be 1305mm. The back cut length value is calculated to be 2000mm-1305mm=695mm based on the actual growth length and the target growth length.

[0093] The back cut length value 695mm is transmitted to the automatic cutting system, and the cutting equipment cuts according to the value. The tail resistance of the cut single crystal silicon rod is detected to be 0.54Ω·cm, which meets the target tail resistance requirement.

[0094] In one embodiment, the embodiments of the present application are compared with the artificial detection method, and the results are shown in Table 1. The traditional artificial detection method takes 5 minutes per root, and the scheme provided by the embodiments of the present application realizes automatic calculation through the target segregation model, and the whole process takes ≤1 minute per root, which is 6-12 times more efficient. The embodiments of the present application avoid process interruption by adopting a closed-loop feedback system, and the utilization rate of the single crystal furnace is increased from 68% to 83%, and the production capacity is increased by 22%. The error of the artificial detection method is ±20mm, and the error of the experience model is ±30mm. The method provided by the embodiments of the present application realizes an error of ≤3mm, and the cutting precision is increased by 5-6 times. After cutting in the traditional process, the tail resistance is detected, and the qualified rate is 70%-80%. The embodiments of the present application realize real-time detection and adaptive cutting, and the qualified rate is increased to more than 95% (compared with the traditional artificial detection method, which is increased by 15%-25%). The loss rate of silicon material (overcut rate) is ≥15% in the traditional way, the embodiments of the present application accurately calculate the reverse cutting length value, and the loss rate of silicon material is ≤5%, and 100mm-300mm of silicon material (2000mm) is saved per single silicon rod (1000 tons per year). The doping type supported by the embodiments of the present application includes P-type (boron), N-type (phosphorus), low segregation coefficient dopant (gallium), etc.; the silicon rod diameter is adapted to mainstream specifications such as 200mm, 300mm and 450mm; and the resistance range covers 0.2Ω·cm-5Ω·cm, which meets the demand of semiconductor-grade and photovoltaic-grade silicon rods. The accuracy of the abnormality detection of the embodiments of the present application is ≥95%, while the accuracy of the traditional artificial detection is only 60%; the labor cost is reduced by 80% (the demand for detection and cutting posts is reduced); and the waste recovery cost is reduced by 50% (silicon scraps are reduced and can be recycled). The adaptive cutting parameters (such as the bevel cutting angle ±5°) of the embodiments of the present application make the crack depth of the fracture surface <10μm (the traditional process is 50-100μm); and the standard deviation of the silicon rod resistance consistency is optimized from ±0.3Ω·cm to ±0.05Ω·cm.

[0095] Table 1 Comparison table of traditional technology and effects of the present application

[0096]

[0097] In one embodiment, a silicon wafer is also provided, which is cut from a single crystal silicon rod prepared by the method provided in any of the above embodiments.

[0098] It should be understood that although each step in the flowchart involved in the above-described embodiments is shown in sequence according to the direction of the arrow, these steps are not necessarily executed in the order indicated by the arrow. Unless otherwise specified herein, the execution of these steps is not strictly limited in sequence, and these steps can be executed in other sequences. Moreover, at least some of the steps in the flowchart involved in the above-described embodiments can include multiple steps or multiple stages, which are not necessarily executed at the same time but can be executed at different times, and the execution of these steps or stages is not necessarily sequential but can be performed alternately or alternately with at least some of the other steps or steps or stages in other steps. It can be understood that the steps in different embodiments can be freely combined as needed, and various non-contradictory schemes formed by the combination are within the scope of protection of the present application.

[0099] Based on the same inventive concept, the embodiments of the present application also provide a single crystal silicon rod production device for implementing the above-mentioned single crystal silicon rod production method. The implementation scheme for solving the problem provided by the device is similar to the implementation scheme described in the above method, so the specific limitations in one or more single crystal silicon rod production device embodiments provided below can refer to the limitations of the single crystal silicon rod production method described above, and will not be repeated here.

[0100] In one exemplary embodiment, as shown in Figure 7 A single crystal silicon rod production device is provided, comprising: a first acquisition module 11, a second acquisition module 12, a generation module 13, and a cutting module 14, wherein:

[0101] The first acquisition module 11 is configured to acquire related parameters of a single crystal silicon rod.

[0102] The second acquisition module 12 is configured to acquire a target segregation model corresponding to the single crystal silicon rod according to the related parameters of the single crystal silicon rod. The target segregation model represents the mapping relationship between the impurity concentration and the crystal generation length of the single crystal silicon rod.

[0103] The generation module 13 is configured to generate a target cutting instruction according to the related parameters of the single crystal silicon rod and the target segregation model.

[0104] The cutting module 14 is configured to cut the single crystal silicon rod according to the target cutting instruction.

[0105] In one embodiment, the generation module 13 is specifically configured to determine a target growth length of the single crystal silicon according to the target tail resistance of the single crystal silicon rod and the target segregation model, and generate the target cutting instruction according to the actual growth length of the single crystal silicon rod and the target growth length.

[0106] In one embodiment, the generating module 13 is specifically configured to determine the solidification percentage of the single crystal silicon rod according to the target segregation model and the target tail resistance of the single crystal silicon rod; determine the solidified silicon melt weight of the single crystal silicon rod when the target tail resistance is reached according to the solidification percentage of the single crystal silicon rod and the initial silicon melt weight; and determine the target growth length corresponding to the silicon melt weight according to the silicon melt weight and the length conversion coefficient.

[0107] In one embodiment, the generating module 13 is specifically configured to determine the length conversion coefficient of the single crystal silicon rod according to the density and radius of the single crystal silicon rod.

[0108] In one embodiment, the cutting module 14 is specifically configured to generate a target cutting instruction according to a target cutting point; obtain a first tail detection resistance of the single crystal silicon rod in the process of cutting the single crystal silicon rod by using the target cutting instruction, and regenerate the target cutting instruction according to the first tail detection resistance; and cut the single crystal silicon rod according to the regenerated target cutting instruction.

[0109] In one embodiment, the target cutting instruction includes a back cut length value and a cutting parameter of a cutting device.

[0110] In one embodiment, the back cut length value ranges from 0 mm to 500 mm.

[0111] In one embodiment, the single crystal silicon rod manufacturing device further includes:

[0112] The first determining module is configured to determine the head impurity concentration of the single crystal silicon rod according to the head resistance of the single crystal silicon rod.

[0113] The second determining module is configured to determine the initial silicon melt concentration of the single crystal silicon rod according to the head impurity concentration of the single crystal silicon rod and the corresponding segregation coefficient of the single crystal silicon rod.

[0114] The third determining module is configured to obtain the target segregation model according to the initial silicon melt concentration and the segregation coefficient.

[0115] In one embodiment, the single crystal silicon rod manufacturing device further includes:

[0116] The third obtaining module is configured to obtain a second tail detection resistance of the cut single crystal silicon rod and a detection impurity concentration corresponding to the second tail detection resistance.

[0117] The optimization module is configured to optimize the segregation coefficient in the target segregation model according to the second tail detection resistance, the detection impurity concentration corresponding to the second tail detection resistance, the target tail resistance, and the impurity concentration corresponding to the target tail resistance.

[0118] In one exemplary embodiment, a computer device is provided, which can be a server, and an internal structure diagram of the computer device can be as shown in Figure 8As shown in the figure. The computer device includes a processor, a memory, an Input / Output (I / O) interface and a communication interface. Among them, the processor, the memory and the input / output interface are connected through the system bus, and the communication interface is connected to the system bus through the input / output interface. Among them, the processor of the computer device is used to provide computing and control capability. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store the related data of the production of the single crystal silicon rod. The input / output interface of the computer device is used to exchange information between the processor and the external device. The communication interface of the computer device is used to communicate with the terminal outside through the network connection. The computer program is executed by the processor to realize a method for producing a single crystal silicon rod.

[0119] Those skilled in the art can understand that, Figure 8 The structure shown in the figure is only a block diagram of part of the structure related to the scheme of the present application, and does not constitute a limitation on the computer device to which the scheme of the present application is applied. The specific computer device can include more or fewer components than those shown in the figure, or combine certain components, or have a different component arrangement.

[0120] In one exemplary embodiment, a computer device is provided, including a memory and a processor, the memory storing a computer program, and the processor executing the computer program to realize the steps of any of the above method embodiments.

[0121] In one embodiment, a computer readable storage medium is provided, having a computer program stored thereon, and the computer program is executed by the processor to realize the steps of any of the above method embodiments.

[0122] In one embodiment, a computer program product is provided, including a computer program, and the computer program is executed by the processor to realize the steps of any of the above method embodiments.

[0123] It should be noted that the user information (including but not limited to user equipment information, user personal information, etc.) and data (including but not limited to data for analysis, stored data, displayed data, etc.) involved in the present application are all information and data authorized by the user or authorized by all parties, and the collection, use and processing of related data need to comply with relevant regulations.

[0124] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a non-volatile computer readable storage medium, and when executed, can include the processes of the above-mentioned embodiment methods. Any reference to memory, database or other medium used in the embodiments provided in the present application can include at least one of non-volatile memory and volatile memory. The non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical storage, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetoresistive random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. The volatile memory can include random access memory (RAM) or external cache memory, etc. As an illustration but not limitation, the RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc. The database involved in the embodiments provided in the present application can include at least one of a relational database and a non-relational database. The non-relational database can include a distributed database based on a block chain, etc., without being limited thereto. The processor involved in the embodiments provided in the present application can be a general-purpose processor, a central processing unit, a graphics processing unit, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, an artificial intelligence (AI) processor, etc., without being limited thereto.

[0125] The technical features of the above embodiments can be combined in any manner. To make the description concise, all possible combinations of the technical features in the above embodiments are not described, but as long as the combinations of the technical features do not exist, they should be considered as the scope of the present application.

[0126] The above-described embodiments are merely illustrative of several embodiments of the present application, which are described in more detail and in a specific manner, but should not be construed as limiting the scope of the patent of the present application. It should be noted that, for those of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. A method of producing a single crystal silicon ingot, characterized by, The method comprises the following steps: obtaining the related parameters of a single crystal silicon rod; obtaining a target segregation model corresponding to the single crystal silicon rod according to the related parameters of the single crystal silicon rod; the target segregation model represents the mapping relationship between the impurity concentration and the crystal generation length of the single crystal silicon rod; generating a target cutting instruction according to the related parameters of the single crystal silicon rod and the target segregation model; cutting the single crystal silicon rod according to the target cutting instruction.

2. The method of producing a single crystal silicon ingot according to claim 1, wherein The related parameters include the target tail resistance of the single crystal silicon rod and the actual growth length of the single crystal silicon rod; the target cutting instruction is generated according to the related parameters of the single crystal silicon rod and the target segregation model, which comprises the following steps: determining the target growth length of the single crystal silicon according to the target tail resistance of the single crystal silicon rod and the target segregation model; generating the target cutting instruction according to the actual growth length of the single crystal silicon rod and the target growth length.

3. The method of producing a single crystal silicon ingot according to claim 2, wherein The target growth length of the single crystal silicon is determined according to the target tail resistance of the single crystal silicon rod and the target segregation model, which comprises the following steps: determining the solidification percentage of the single crystal silicon rod according to the target segregation model and the target tail resistance of the single crystal silicon rod; determining the weight of the solidified silicon melt of the single crystal silicon rod when the target tail resistance is reached according to the solidification percentage of the single crystal silicon rod and the initial weight of the silicon melt; determining the target growth length corresponding to the weight of the silicon melt according to the weight of the silicon melt and the length conversion coefficient.

4. The method of producing a single crystal silicon ingot according to claim 3, wherein The method for manufacturing the single crystal silicon rod further comprises the following steps: determining the length conversion coefficient of the single crystal silicon rod according to the density and radius of the single crystal silicon rod.

5. The method of producing a single crystal silicon ingot according to claim 2, wherein The single crystal silicon rod is cut according to the target cutting instruction, which comprises the following steps: determining the target cutting point according to the actual growth length of the single crystal silicon rod and the target growth length; generating the target cutting instruction according to the target cutting point; re-generating the target cutting instruction according to the first tail detection resistance of the single crystal silicon rod in the process of cutting the single crystal silicon rod by using the target cutting instruction; cutting the single crystal silicon rod according to the re-generated target cutting instruction.

6. The method of producing a single crystal silicon ingot according to claim 5, wherein The target cutting instruction comprises a back-cut length value and the cutting parameters of a cutting device.

7. The method of producing a single crystal silicon ingot according to claim 6, wherein The range of the back-cut length value is 0mm-500mm.

8. The method of producing a single crystal silicon ingot according to Claim 1, wherein The related parameters include the head resistance of the single crystal silicon rod; the target segregation model corresponding to the single crystal silicon rod is obtained according to the related parameters of the single crystal silicon rod, which comprises the following steps: determining the head impurity concentration of the single crystal silicon rod according to the head resistance of the single crystal silicon rod; determining the initial concentration of the silicon melt of the single crystal silicon rod according to the head impurity concentration of the single crystal silicon rod and the segregation coefficient corresponding to the single crystal silicon rod; obtaining the target segregation model according to the initial concentration of the silicon melt and the segregation coefficient.

9. The method of producing a single crystal silicon ingot according to claim 8, wherein The method for manufacturing the single crystal silicon rod further comprises the following steps: obtaining the second tail detection resistance of the single crystal silicon rod after cutting and the detection impurity concentration corresponding to the second tail detection resistance; According to the second tail detection resistance, the detection impurity concentration corresponding to the second tail detection resistance, the target tail resistance and the impurity concentration corresponding to the target tail resistance, the fractional condensation coefficient in the target fractional condensation model is optimized.

10. A silicon wafer, characterized by, The silicon wafer is cut from the single crystal silicon rod prepared by the method of any one of claims 1-9.

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