Control method and device of crystal pulling process and crystal pulling system

Abstract

The invention provides a crystal pulling process control method and device and a crystal pulling system.The method comprises the steps that a transport numerical model of a target object in a single crystal furnace is built, and the target object comprises at least one of oxygen impurities and a phosphorus doping agent, the transport numerical model of the target object is used for reflecting the distribution condition of the target object in the single crystal furnace under different process conditions and magnetic field structures; according to the transport numerical model of the target object, a plurality of characteristic parameters corresponding to the target object under the plurality of process conditions and the plurality of magnetic field structure parameters are generated, and the characteristic parameters are used for representing physical characteristics of the target object; and according to the plurality of characteristic parameters, screening a target process condition and a target magnetic field structure parameter from the plurality of process conditions and the plurality of magnetic field structure parameters so as to control the single crystal furnace to perform a crystal pulling process under the target process condition and the target magnetic field structure parameter, therefore, the problem that the electrical property of the crystal cannot be guaranteed due to a czochralski method silicon single crystal rod growth process in the prior art is solved.

Description

Technical Field

[0001] The present application relates to the technical field of direct-pulling single-crystal silicon, and in particular to a control method, device and crystal pulling system for a crystal pulling process. Background Art

[0002] The Czochralski crystal growth process is an important technology and method for pulling semiconductor single crystal rods. It can produce high-purity, high-quality silicon single crystals and is an important foundation in the semiconductor materials industry.

[0003] As an important semiconductor material, the growth technology of single crystal silicon has a profound impact on the manufacture of high-purity silicon, solar cells, as well as aerospace, microelectronics and other fields. The Czochralski method is also the most important growth technology at present. The surface of N-type single crystal silicon rod has a good band structure and is often used to manufacture the N-type region of solar cells. N-type doping is a key factor in determining the quality of single crystal silicon rods. The distribution uniformity of dopants (P, As, B, Sb) directly affects the electrical properties of single crystal silicon.

[0004] However, there are many challenges in the growth of single crystal silicon rods. Among them: oxygen impurities introduced during the growth of single crystal silicon by the Czochralski method will reduce the minority carrier lifetime of the silicon wafer, which is not conducive to improving the efficiency of photovoltaic cells. The high concentration of oxygen impurities on the surface of the crystal will lead to poor surface energy band structure; and the uneven distribution of phosphorus in N-type silicon wafers will affect the resistivity and distribution of the silicon wafer, resulting in fluctuations and attenuation of the minority carrier lifetime during the crystal growth process, thereby affecting the electrical properties of the crystal. Summary of the invention

[0005] The main purpose of the present application is to provide a control method, device and crystal pulling system for a crystal pulling process, so as to at least solve the problem in the prior art that the electrical properties of the crystal cannot be guaranteed due to the Czochralski single crystal silicon rod growth process.

[0006] In order to achieve the above-mentioned purpose, according to one aspect of the present application, a control method for a crystal pulling process is provided, comprising: constructing a transport numerical model of a target object in a single crystal furnace, the target object including at least one of oxygen impurities and phosphorus dopants, wherein the transport numerical model of the target object is used to at least reflect the distribution of the target object inside the single crystal furnace under different process conditions and magnetic field structures; based on the transport numerical model of the target object, generating a plurality of characteristic parameters corresponding to the target object under multiple process conditions and multiple magnetic field structure parameters, wherein the characteristic parameters are used to characterize the physical properties of the target object; based on the plurality of characteristic parameters, selecting target process conditions and target magnetic field structure parameters from the plurality of process conditions and the plurality of magnetic field structure parameters to control the single crystal furnace to perform a crystal pulling process under the target process conditions and the target magnetic field structure parameters.

[0007] Optionally, the target object includes oxygen impurities, and constructing a transport numerical model of the target object in the single crystal furnace includes: establishing a first theoretical relationship for the dissolution rate of oxygen on the contact surface between the crucible and the silicon melt in the single crystal furnace under different process conditions and magnetic field structures based on multiple first historical experimental data under multiple process conditions and multiple magnetic field structure parameters and non-equilibrium molecular dynamics theory, wherein the multiple first historical experimental data include: the dissolution rate of oxygen in the single crystal furnace, and the oxygen concentration in the single crystal furnace; and constructing a transport numerical model of the oxygen impurities based on the first theoretical relationship.

[0008] Optionally, the target object includes a phosphorus dopant, and constructing a transport numerical model of the target object in the single crystal furnace includes: constructing a transport numerical model of the phosphorus dopant based on a plurality of second historical experimental data under a plurality of the process conditions and a plurality of the magnetic field structure parameters, wherein the plurality of the second historical experimental data include: the phosphorus dopant concentration in the single crystal furnace, and the resistivity of the single crystal silicon prepared by the single crystal furnace.

[0009] Optionally, the method generates multiple characteristic parameters corresponding to the target object under multiple process conditions and multiple magnetic field structure parameters according to the transport numerical model of the target object, including: performing calculations according to the transport numerical model of the oxygen impurity to obtain calculation results corresponding to multiple melt systems, wherein the calculation results include a dynamic relationship between an input set and an output set of the transport numerical model, and the dynamic relationship is used to reflect the physical properties corresponding to the multiple melt systems, any two of the melt systems have different dynamic properties, and the multiple melt systems correspond to multiple process conditions and multiple magnetic field structure parameters respectively, wherein: when the target object includes oxygen impurities, the physical properties include at least one of the following: oxygen impurities in the raw material The target object includes oxygen impurities, the physical properties include at least one of the following: the occurrence characteristics of oxygen impurities in the raw materials, the dissolution characteristics of oxygen impurities in the crucible wall, the transport characteristics of oxygen impurities in the silicon melt, the segregation characteristics of oxygen impurities at the crystal interface, the evaporation characteristics of oxygen impurities on the melt surface, and the distribution laws of oxygen impurities along the radial and axial directions of the crystal; when the target object includes oxygen impurities, the physical properties include at least one of the following: the occurrence characteristics of oxygen impurities in the raw materials, the dissolution characteristics of oxygen impurities in the crucible wall, the transport characteristics of oxygen impurities in the silicon melt, the segregation characteristics of oxygen impurities at the crystal interface, the evaporation characteristics of oxygen impurities on the melt surface, and the distribution laws of oxygen impurities along the radial and axial directions of the crystal; according to the calculation results, multiple preset process conditions and multiple preset magnetic field structure parameters, determine multiple characteristic parameters corresponding to the multiple melt systems respectively.

[0010] Optionally, the method of determining multiple characteristic parameters corresponding to multiple melt systems based on the calculation results, multiple preset process conditions and multiple preset magnetic field structure parameters includes: obtaining characteristic parameters corresponding to multiple melt systems based on the calculation results, multiple preset rotational speeds and multiple preset hook-shaped magnetic field structure parameters, wherein the preset rotational speed includes at least: the crucible rotational speed of the single crystal furnace, and the crystal rotational speed of the single crystal furnace, the preset hook-shaped magnetic field structure parameters include at least: the position and intensity of the hook-shaped magnetic field, and the characteristic parameters include at least one of the following: the concentration distribution of the oxygen impurities, the crystal growth rate in the single crystal furnace, and the temperature distribution in the single crystal furnace.

[0011] Optionally, the target process conditions and target magnetic field structure parameters are screened from the multiple process conditions and the multiple magnetic field structure parameters based on the multiple characteristic parameters, including: judging whether the multiple characteristic parameters meet corresponding preset conditions; when a first target characteristic parameter among the multiple characteristic parameters meets the target preset condition, determining the process conditions and the magnetic field structure parameters corresponding to the first target characteristic parameter as the target process conditions and target magnetic field structure parameters.

[0012] Optionally, the control method also includes: an adjustment step: when the first target characteristic parameter does not meet the target preset condition, outputting an adjustment signal to the single crystal furnace to adjust the process conditions and the magnetic field structure parameters corresponding to the first target characteristic parameter; a determination step: re-determining the updated first target characteristic parameter corresponding to the target object under the adjusted process conditions and / or magnetic field structure parameters based on the transport numerical model of the target object; a judgment step: judging whether the first target characteristic parameter meets the target preset condition; when the first target characteristic parameter does not meet the target preset condition, repeating the adjustment step, the determination step and the judgment step until the first target characteristic parameter meets the target preset condition and stops.

[0013] Optionally, when the single crystal furnace receives the adjustment signal, it grows single crystal silicon using the adjusted process conditions and / or magnetic field structure parameters, and the determination step includes: generating a second target characteristic parameter corresponding to the target object under the adjusted process conditions and / or magnetic field structure parameters based on a transport numerical model of the target object, the second target characteristic parameter being a characteristic parameter different from the first target characteristic parameter among a plurality of characteristic parameters; obtaining target experimental data for the growth of the single crystal silicon, wherein the target experimental data and the second target characteristic parameter have the same characteristic type; determining whether the difference between the second target characteristic parameter and the experimental data satisfies a preset difference; and if the preset difference is satisfied, determining that the second target characteristic parameter is the updated first target characteristic parameter.

[0014] According to another aspect of the present application, a process control device for a single crystal silicon rod is provided, comprising: a construction module, for constructing a transport numerical model of a target object in a single crystal furnace, the target object comprising at least one of oxygen impurities and phosphorus dopants, wherein the transport numerical model of the target object is used to at least reflect the distribution of the target object inside the single crystal furnace under different process conditions and magnetic field structures; a generation module, for generating, according to the transport numerical model of the target object, a plurality of characteristic parameters corresponding to the target object under a plurality of process conditions and a plurality of magnetic field structure parameters, wherein the characteristic parameters are used to characterize the physical properties of the target object; and a control module, for selecting, according to a plurality of the characteristic parameters, target process conditions and target magnetic field structure parameters from a plurality of the process conditions and a plurality of the magnetic field structure parameters, so as to control the single crystal furnace to perform a crystal pulling process under the target process conditions and the target magnetic field structure parameters.

[0015] According to another aspect of the present application, a crystal pulling system is provided, comprising: a single crystal furnace, one or more processors, a memory, and one or more programs, wherein the one or more processors are electrically connected to the single crystal furnace, the one or more programs are stored in the memory and are configured to be executed by the one or more processors, and the one or more programs include a control method for executing the crystal pulling process.

[0016] By applying the technical solution of the present application, a transport numerical model of target objects such as oxygen impurities and phosphorus dopants is established to at least reflect the distribution of the target objects inside the single crystal furnace under different process conditions and magnetic field structures, and based on the above transport numerical model, the physical properties of the above target objects in the melt and crystal at different stages of single crystal silicon growth under different process conditions and magnetic field structures are studied, so as to develop a transport regulation technology for target objects such as oxygen impurities and phosphorus dopants in the magnetically controlled N-type single crystal silicon pulling growth. Furthermore, through process parameter optimization and magnetic field structure matching, not only can the reduction and uniform distribution of oxygen impurity concentration in the crystal be achieved, so as to reduce the decay rate of minority carrier lifetime during crystal growth, which is beneficial to improving the efficiency of photovoltaic cells, but also the uniformity of phosphorus distribution in N-type single crystal silicon can be improved, so as to improve the resistivity uniformity of N-type single crystal silicon and slow down or avoid the fluctuation and attenuation of minority carrier lifetime during crystal growth. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings constituting part of the present application are used to provide a further understanding of the present application. The exemplary embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0018] Figure 1 A hardware structure block diagram of a mobile terminal for executing a control method for a crystal pulling process provided in an embodiment of the present application is shown;

[0019] Figure 2 A schematic flow chart of a control method for a crystal pulling process provided in accordance with an embodiment of the present application is shown;

[0020] Figure 3 A structural block diagram of a control device for a crystal pulling process provided according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0021] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0022] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0023] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0024] As introduced in the background technology, oxygen impurities introduced during the traditional Czochralski method of single crystal silicon growth in the prior art will reduce the minority carrier lifetime of the silicon wafer, which is not conducive to improving the efficiency of photovoltaic cells. The high concentration of oxygen impurities on the crystal surface will lead to poor surface energy band structure. In addition, the uneven distribution of phosphorus elements in N-type silicon wafers will affect the resistivity and distribution of the silicon wafer, resulting in fluctuations and attenuation of the minority carrier lifetime during the crystal growth process, thereby affecting the electrical properties of the crystal. To solve the above problems, the embodiments of the present application provide a control method, device, storage medium and crystal pulling system for a crystal pulling process.

[0025] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0026] The method embodiments provided in the embodiments of the present application can be executed in a mobile terminal, a computer terminal or a similar computing device. Taking running on a mobile terminal as an example, Figure 1 FIG. 1 is a hardware structure block diagram of a mobile terminal for a method for controlling a crystal pulling process according to an embodiment of the present invention. Figure 1 As shown, the mobile terminal may include one or more ( Figure 1 Only one is shown in the figure) a processor 102 (the processor 102 may include but is not limited to a processing device such as a microprocessor MCU or a programmable logic device FPGA) and a memory 104 for storing data, wherein the mobile terminal may also include a transmission device 106 and an input / output device 108 for communication functions. It can be understood by those skilled in the art that Figure 1 The structure shown is only for illustration and does not limit the structure of the mobile terminal. Figure 1 More or fewer components as shown, or with Figure 1 Different configurations shown.

[0027] The memory 104 can be used to store computer programs, for example, software programs and modules of application software, such as the computer program corresponding to the control method of the crystal pulling process in the embodiment of the present invention. The processor 102 executes various functional applications and data processing by running the computer program stored in the memory 104, that is, the above method is implemented. The memory 104 may include a high-speed random access memory, and may also include a non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some examples, the memory 104 may further include a memory remotely arranged relative to the processor 102, and these remote memories can be connected to the mobile terminal via a network. Examples of the above-mentioned network include but are not limited to the Internet, an intranet, a local area network, a mobile communication network, and a combination thereof. The transmission device 106 is used to receive or send data via a network. The above-mentioned specific examples of the network may include a wireless network provided by a communication provider of the mobile terminal. In one example, the transmission device 106 includes a network adapter (Network Interface Controller, referred to as NIC), which can be connected to other network devices through a base station so as to communicate with the Internet. In one example, the transmission device 106 may be a radio frequency (RF) module, which is used to communicate with the Internet wirelessly.

[0028] In this embodiment, a method for controlling a crystal pulling process running on a mobile terminal, a computer terminal or a similar computing device is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0029] Figure 2 1 is a flow chart of a method for controlling a crystal pulling process according to an embodiment of the present application. Figure 2 As shown, the method comprises the following steps:

[0030] Step S201, constructing a transport numerical model of a target object in a single crystal furnace, wherein the target object includes at least one of an oxygen impurity and a phosphorus dopant, wherein the transport numerical model of the target object is used to at least reflect the distribution of the target object inside the single crystal furnace under different process conditions and magnetic field structures;

[0031] Specifically, the above-mentioned transport numerical model can be used to study the physical properties of the above-mentioned target objects in the melt and crystal at different stages of single crystal silicon growth under different process conditions and magnetic field structures, so as to develop transport control technology for target objects such as oxygen impurities and phosphorus dopants in magnetically controlled N-type single crystal silicon pulling growth.

[0032] Step S202, generating a plurality of characteristic parameters corresponding to the target object under a plurality of process conditions and a plurality of magnetic field structure parameters according to the transport numerical model of the target object, wherein the characteristic parameters are used to characterize the physical properties of the target object;

[0033] Specifically, according to the transport numerical model of the target object constructed, characteristic parameters of the target object under different process conditions and magnetic field structure parameters can be generated. These characteristic parameters can characterize the physical properties of the target object, including but not limited to the transport characteristics inside the silicon melt, the segregation characteristics at the crystal interface, the evaporation characteristics on the surface of the silicon melt, and the distribution laws along the radial and axial directions of the crystal. By comparing and analyzing these parameters, the consumption of oxygen impurities, phosphorus dopants and other target objects and the influence of their distribution in the crystal at different stages of single crystal silicon growth under the influence of different process conditions and magnetic field structure parameters can be studied.

[0034] Step S203, determining target process conditions and target magnetic field structure parameters according to multiple characteristic parameters, multiple process conditions and multiple magnetic field structure parameters, and controlling the single crystal furnace to perform a crystal pulling process under the target process conditions and target magnetic field structure parameters.

[0035] Specifically, based on the generated characteristic parameters, a set of optimal target process conditions and target magnetic field structure parameters can be determined in combination with historical experimental data. The selection of these parameters aims to improve the uniformity of the distribution of the target object in N-type single crystal silicon and avoid the influence of its uneven distribution on the minority carrier lifetime during the crystal growth process. Then, the determined target process conditions and magnetic field structure parameters are applied to the actual single crystal furnace control, and the single crystal furnace is ensured to operate under optimal conditions by adjusting parameters such as the crucible speed, crystal speed, hook-shaped magnetic field position and intensity. This control method can specifically solve the problems of uneven distribution of oxygen impurities and difficult control of phosphorus dopant transport in the existing process, thereby significantly improving the quality of Czochralski single crystal silicon rods.

[0036] Through this embodiment, a transport numerical model of target objects such as oxygen impurities and phosphorus dopants can be established and utilized to reflect the distribution of the target objects inside the single crystal furnace under different process conditions and magnetic field structures, and based on the above transport numerical model, the physical properties of the above target objects in the melt and crystal at different stages of single crystal silicon growth under different process conditions and magnetic field structures are studied, so as to develop a transport control technology for target objects such as oxygen impurities and phosphorus dopants in magnetically controlled N-type single crystal silicon pulling growth. Furthermore, through process parameter optimization and magnetic field structure matching, not only can the reduction and uniform distribution of oxygen impurity concentration in the crystal be achieved to reduce the decay rate of minority carrier lifetime during crystal growth, which is beneficial to improving the efficiency of photovoltaic cells, but also the uniformity of phosphorus distribution in N-type single crystal silicon can be improved to improve the resistivity uniformity of N-type single crystal silicon and slow down or avoid the fluctuation and attenuation of minority carrier lifetime during crystal growth.

[0037] On the one hand, oxygen impurities introduced during the growth of single crystal silicon by the Czochralski method will reduce the minority carrier lifetime of silicon wafers, which is not conducive to improving the efficiency of photovoltaic cells. In view of this problem, in the case where the above target object includes oxygen impurities, the above step S201 can be implemented by the following steps: according to multiple first historical experimental data under multiple process conditions and multiple magnetic field structure parameters and non-equilibrium molecular dynamics theory, a first theoretical relationship of the dissolution rate of oxygen on the contact surface between the crucible and the silicon melt in the single crystal furnace under different process conditions and magnetic field structures is established, wherein the multiple first historical experimental data include: the dissolution rate of oxygen in the single crystal furnace, and the oxygen concentration in the single crystal furnace, and according to the first theoretical relationship, a transport numerical model of oxygen impurities is constructed.

[0038] Illustratively, this application constructs an atomic-scale model of quartz dissolution in silicon melt based on nonequilibrium molecular dynamics theory and related experimental data, compares and studies the changes in oxygen dissolution rate and oxygen concentration over time at different temperatures, reveals the influence of temperature and oxygen concentration on the oxygen dissolution rate, obtains the theoretical relationship between the dissolution rate of oxygen on the contact surface between quartz and silicon melt, and establishes a numerical model that can accurately describe the generation, consumption and transport of oxygen impurities during the growth of magnetically controlled N-type single crystal silicon.

[0039] On the other hand, the distribution of phosphorus in N-type silicon wafers has a significant effect on the resistivity and distribution of silicon wafers, which is closely related to the transport process of phosphorus dopants during the growth of single crystal silicon. In view of this problem, in the case where the target object includes phosphorus dopants, the above step S201 can be implemented by the following steps: constructing a transport numerical model of phosphorus dopants based on multiple second historical experimental data under multiple process conditions and multiple magnetic field structure parameters, wherein the multiple second historical experimental data include: the concentration of phosphorus dopants in the single crystal furnace, and the resistivity of single crystal silicon prepared by the single crystal furnace.

[0040] Exemplarily, the present application considers the volatilization of phosphorus at the free liquid surface, the segregation at the crystallization interface, and the free diffusion inside the crystal. Based on the volatilization loss of phosphorus from the melt surface during the pulling process, the experimental data related to the segregation characteristics of phosphorus at the crystallization interface, and the diffusion coefficient of phosphorus inside the crystal, a numerical model of the transport of dopant phosphorus in magnetically controlled N-type single crystal silicon grown by the pulling method is established.

[0041] In order to generate characteristic parameters for characterizing the physical properties of the target object, the above-mentioned step S202 of the present application can be implemented by the following steps: performing calculations according to the transport numerical model of the target object to obtain calculation results corresponding to multiple melt systems, wherein the calculation results include a dynamic relationship between an input set and an output set of the transport numerical model, and the dynamic relationship is used to reflect the physical properties corresponding to the multiple melt systems, any two melt systems have different dynamic properties, and the multiple melt systems respectively correspond to multiple preset process conditions and multiple magnetic field structure parameters; based on the calculation results, the multiple preset process conditions and the multiple magnetic field structure parameters, determine multiple characteristic parameters corresponding to the multiple melt systems respectively.

[0042] In some optional embodiments, multiple characteristic parameters corresponding to multiple melt systems are determined based on calculation results, multiple preset process conditions and multiple preset magnetic field structure parameters, including: obtaining characteristic parameters corresponding to multiple melt systems based on calculation results, multiple preset rotational speeds and multiple preset hook-shaped magnetic field structure parameters, wherein the preset rotational speed includes at least: the crucible rotational speed of the single crystal furnace, and the crystal rotational speed of the single crystal furnace, the preset hook-shaped magnetic field structure parameters include at least: the position and intensity of the hook-shaped magnetic field, and the characteristic parameters include at least one of the following: the concentration distribution of oxygen impurities, the crystal growth rate in the single crystal furnace, and the temperature distribution in the single crystal furnace.

[0043] In the above optional implementation, the established transport numerical model of the target object can be used to study and analyze the physical characteristics of the target object under different process conditions (such as crucible speed, crystal speed, temperature, pressure, etc.) and hook-shaped magnetic field structures (magnetic field position, intensity, distribution, etc.), so as to identify the key parameters affecting the distribution of the target object.

[0044] Specifically, in the case where the above-mentioned target object includes oxygen impurities, the physical properties of oxygen impurities may include one of the following: the occurrence characteristics of oxygen impurities in raw materials, the dissolution characteristics of oxygen impurities on the wall of the crucible, the transport characteristics of oxygen impurities in the silicon melt, the segregation characteristics of oxygen impurities at the crystal interface, the evaporation characteristics of oxygen impurities on the melt surface, and the distribution law of oxygen impurities along the radial and axial directions of the crystal. In this application, based on the above-mentioned transport numerical model of oxygen impurities and crystal growth experiments, the occurrence characteristics of oxygen impurities in raw materials, the segregation characteristics of oxygen impurities at the crystal interface, and the evaporation characteristics of oxygen impurities on the free surface of the melt and the distribution law along the radial and axial directions of the crystal are studied, and the free surface interface effect is analyzed, so as to analyze the influence of process parameters such as crucible speed, crystal speed, and the position and strength of the hook-shaped magnetic field on the generation, consumption and distribution of oxygen impurities in the crystal at different stages of single crystal silicon growth, so as to obtain the key parameters affecting the distribution of oxygen impurities, especially the regulatory effect of the hook-shaped magnetic field on oxygen transport.

[0045] In the case where the above-mentioned target object includes a phosphorus dopant, the physical properties of the phosphorus dopant may include one of the following: transport characteristics of the phosphorus dopant inside the silicon melt, segregation characteristics of the phosphorus dopant at the crystal interface, evaporation characteristics of the phosphorus dopant on the surface of the silicon melt, and the distribution law of the phosphorus dopant along the radial and axial directions of the crystal.

[0046] Specifically, based on the above-mentioned numerical transport model of phosphorus dopants and crystal growth experiments, with the purpose of inhibiting the volatilization loss of phosphorus from the melt surface during the melting and pulling process, the segregation characteristics of phosphorus at the crystal interface, the evaporation characteristics on the free surface of the melt, and the distribution laws along the radial and axial directions of the crystal are studied, so as to inhibit the volatilization loss of phosphorus from the melt surface during the melting and pulling process. The consumption of phosphorus dopants and their distribution in the crystal at different stages of single crystal silicon growth under the influence of process parameters such as crucible rotation speed, crystal rotation speed, and the position and intensity of the y-type magnetic field are studied, so as to obtain the key parameters affecting the distribution of phosphorus, especially the regulatory effect of the y-type magnetic field on phosphorus transport.

[0047] In some embodiments, the above-mentioned step S203 can be specifically implemented through the following steps: determining whether multiple characteristic parameters meet corresponding preset conditions; when the first target characteristic parameter among the multiple characteristic parameters meets the target preset conditions, determining the process conditions and magnetic field structure parameters corresponding to the first target characteristic parameter as the target process conditions and target magnetic field structure parameters.

[0048] Specifically, numerical simulation is performed using the established model to analyze the distribution patterns of oxygen impurities and phosphorus elements under different process conditions and magnetic field structures, and how these distributions affect their turbulent transport inside the melt and their segregation at the crystallization interface. Then, preset conditions are set by using the characteristic parameters of the historical silicon melt system with stable transport, and by determining whether the characteristic parameters obtained in step S202 meet the preset conditions, the optimal combination of magnetic field parameters is found from the historical experimental data, which can reduce the turbulent transport of oxygen impurities and phosphorus elements in the melt and control their segregation at the crystallization interface, thereby achieving the optimal distribution of oxygen impurities and phosphorus elements and crystal performance. In addition to the magnetic field parameters, process conditions such as crucible speed, crystal speed, etc. need to be determined to cooperate with the effect of the magnetic field.

[0049] In some optional embodiments, the control method in the embodiment of the present application also includes: an adjustment step: when the target characteristic parameter does not meet the target preset condition, an adjustment signal is output to the single crystal furnace to adjust the process conditions and magnetic field structure parameters corresponding to the first target characteristic parameter; a determination step: re-determining the updated target characteristic parameters corresponding to the target object under the adjusted process conditions and / or magnetic field structure parameters based on the transport numerical model of the target object; a judgment step: judging whether the target characteristic parameter meets the target preset condition; when the target characteristic parameter does not meet the target preset condition, repeating the adjustment step, the determination step and the judgment step until the target characteristic parameter meets the target preset condition and stops.

[0050] Furthermore, when the single crystal furnace receives the adjustment signal, it grows single crystal silicon according to the adjusted process conditions and / or magnetic field structure parameters, and then generates a second target characteristic parameter corresponding to the silicon melt under the adjusted process conditions and / or magnetic field structure parameters according to the transport numerical model of the target object, wherein the second target characteristic parameter is a characteristic parameter different from the first target characteristic parameter among multiple characteristic parameters; and obtains target experimental data for single crystal silicon growth, wherein the target experimental data and the second target characteristic parameter have the same characteristic type; then, it is determined whether the difference between the second target characteristic parameter and the experimental data satisfies a preset difference, and if the preset difference is satisfied, the second target characteristic parameter is determined to be the updated first target characteristic parameter.

[0051] Specifically, the position and intensity of the hook-shaped magnetic field can be adjusted to study its effect on the distribution of target objects such as oxygen impurities and phosphorus elements, and the model prediction can be verified through experiments, and the magnetic field configuration can be gradually optimized to find an optimal magnetic field structure parameter, which can effectively improve the distribution uniformity of target objects such as oxygen impurities and phosphorus elements in N-type single crystal silicon. In addition to the magnetic field structure parameters, process conditions such as crucible speed and crystal speed can also be adjusted to cooperate with the effect of the magnetic field. The adjustment of these parameters can also be based on model predictions and experimental verification to ensure that the concentration distribution state of target objects such as oxygen impurities and phosphorus elements can be effectively controlled during the entire growth process. Finally, through continuous production data collection and analysis, it is verified whether the adjusted magnetic field structure parameters and process conditions can indeed improve the distribution uniformity of target objects in N-type single crystal silicon.

[0052] Through this series of steps in the embodiment of the present application, the hook-shaped magnetic field can be effectively utilized to improve the distribution uniformity of target objects such as oxygen impurities and phosphorus elements in N-type single crystal silicon, reduce the impact of uneven distribution on the minority carrier lifetime during the crystal growth process, and help improve the efficiency of photovoltaic cells.

[0053] The present application also provides a process control device. It should be noted that the process control device of the present application can be used to execute the process control method provided by the present application. The device is used to implement the above-mentioned embodiments and preferred embodiments, and the descriptions have been omitted. As used below, the term "module" can implement a combination of software and / or hardware for a predetermined function. Although the device described in the following embodiments is preferably implemented in software, the implementation of hardware, or a combination of software and hardware, is also possible and conceived.

[0054] The process control device provided in the embodiments of the present application is introduced below.

[0055] Figure 3 Schematic diagram of a process control device according to an embodiment of the present application. Figure 3 As shown, the device comprises:

[0056] A construction module 10 is used to construct a transport numerical model of a target object in a single crystal furnace, wherein the target object includes at least one of an oxygen impurity and a phosphorus dopant, wherein the transport numerical model of the target object is used to at least reflect the distribution of the target object inside the single crystal furnace under different process conditions and magnetic field structures;

[0057] A generating module 20, for generating a plurality of characteristic parameters corresponding to the target object under a plurality of process conditions and a plurality of magnetic field structure parameters according to the transport numerical model of the target object, wherein the characteristic parameters are used to characterize the physical properties of the target object;

[0058] The control module 30 is used to select target process conditions and target magnetic field structure parameters from multiple process conditions and multiple magnetic field structure parameters according to multiple characteristic parameters, so as to control the single crystal furnace to perform a crystal pulling process under the target process conditions and target magnetic field structure parameters.

[0059] As an optional scheme, the target object includes phosphorus dopants, and the construction module 10 includes: an establishment submodule, which is used to establish a first theoretical relationship for the dissolution rate of oxygen on the contact surface between the crucible and the silicon melt in the single crystal furnace under different process conditions and magnetic field structures according to multiple first historical experimental data under multiple process conditions and multiple magnetic field structure parameters and the non-equilibrium molecular dynamics theory, wherein the multiple first historical experimental data include: the dissolution rate of oxygen in the single crystal furnace, and the oxygen concentration in the single crystal furnace; a first construction submodule, which is used to construct a numerical model of oxygen impurity transport according to the first theoretical relationship.

[0060] As another optional scheme, the target object includes oxygen impurities, and the construction module 10 includes: a second construction submodule, used to construct a transport numerical model of phosphorus dopants based on multiple second historical experimental data under multiple process conditions and multiple magnetic field structure parameters, wherein the multiple second historical experimental data include: the phosphorus dopant concentration in the single crystal furnace, and the resistivity of the single crystal silicon prepared by the single crystal furnace.

[0061] In an optional scheme, the generation module 20 includes: a calculation submodule, which is used to perform calculations according to the transport numerical model of oxygen impurities to obtain calculation results corresponding to multiple melt systems, wherein the calculation results include a dynamic relationship between an input set and an output set of the transport numerical model, and the dynamic relationship is used to reflect the physical properties corresponding to the multiple melt systems, any two melt systems have different dynamic properties, and the multiple melt systems correspond to multiple process conditions and multiple magnetic field structure parameters, respectively, wherein: when the target object includes oxygen impurities, the physical properties include at least one of the following: the occurrence characteristics of oxygen impurities in the raw materials, the dissolution characteristics of oxygen impurities on the crucible wall, the transport characteristics of oxygen impurities in the silicon melt, transport characteristics, segregation characteristics of oxygen impurities at the crystallization interface, evaporation characteristics of oxygen impurities on the melt surface, and distribution laws of oxygen impurities along the radial and axial directions of the crystal; when the target object includes oxygen impurities, the physical characteristics include at least one of the following: occurrence characteristics of oxygen impurities in raw materials, dissolution characteristics of oxygen impurities on the crucible wall, transport characteristics of oxygen impurities in the silicon melt, segregation characteristics of oxygen impurities at the crystallization interface, evaporation characteristics of oxygen impurities on the melt surface, and distribution laws of oxygen impurities along the radial and axial directions of the crystal; a first determination submodule is used to determine multiple characteristic parameters corresponding to multiple melt systems respectively according to the calculation results, multiple preset process conditions and multiple preset magnetic field structure parameters.

[0062] In an optional scheme, the first determination submodule is used to obtain characteristic parameters corresponding to multiple melt systems based on calculation results, multiple preset rotational speeds and multiple preset hook-shaped magnetic field structure parameters, wherein the preset rotational speed includes at least: the crucible rotational speed of the single crystal furnace, and the crystal rotational speed of the single crystal furnace, the preset hook-shaped magnetic field structure parameters include at least: the position and intensity of the hook-shaped magnetic field, and the characteristic parameters include at least one of the following: the concentration distribution of oxygen impurities, the crystal growth rate in the single crystal furnace, and the temperature distribution in the single crystal furnace.

[0063] In an optional scheme, the control module 30 includes: a judgment submodule, used to judge whether multiple characteristic parameters meet the corresponding preset conditions; and a second determination submodule, used to determine the process conditions and magnetic field structure parameters corresponding to the first target characteristic parameters as target process conditions and target magnetic field structure parameters when the first target characteristic parameters meet the target preset conditions.

[0064] In an optional scheme, the process control device of an embodiment of the present application also includes: an adjustment module, which is used to output an adjustment signal to the single crystal furnace to adjust the process conditions and magnetic field structure parameters corresponding to the first target characteristic parameters when the first target characteristic parameters do not meet the target preset conditions; a fourth determination submodule, which is used to re-determine the updated first target characteristic parameters corresponding to the silicon melt under the adjusted process conditions and / or magnetic field structure parameters based on the transport numerical model of the target object; a second judgment submodule, which is used to judge whether the first target characteristic parameters meet the target preset conditions; and a loop submodule, which is used to repeat the adjustment step, the determination step and the judgment step when the first target characteristic parameters do not meet the target preset conditions, and stop when the first target characteristic parameters meet the target preset conditions.

[0065] In an optional scheme, when the single crystal furnace receives an adjustment signal, it grows single crystal silicon according to the adjusted process conditions and / or magnetic field structure parameters, and the fourth determination submodule includes: a generation submodule, which is used to generate a second target characteristic parameter corresponding to the silicon melt under the adjusted process conditions and / or magnetic field structure parameters according to the transport numerical model of the target object; an acquisition submodule, which is used to acquire target experimental data for single crystal silicon growth, wherein the target experimental data and the second target characteristic parameter have the same characteristic type; a third judgment submodule, which is used to judge whether the difference between the second target characteristic parameter and the experimental data meets the preset difference; if the preset difference is met, the second target characteristic parameter is determined to be the updated first target characteristic parameter.

[0066] In this embodiment, a construction module 10 is used to establish a transport numerical model of target objects such as oxygen impurities and phosphorus dopants, which is used to at least reflect the distribution of the target objects in the single crystal furnace under different process conditions and magnetic field structures, and a generation module 20 and a control module 30 are used to study the physical properties of the target objects in the melt and the crystal at different stages of single crystal silicon growth under different process conditions and magnetic field structures based on the above transport numerical model, so as to develop a transport control technology for target objects such as oxygen impurities and phosphorus dopants in the magnetically controlled N-type single crystal silicon pulling growth. Then, through process parameter optimization and magnetic field structure matching, not only can the reduction and uniform distribution of oxygen impurity concentration in the crystal be achieved, so as to reduce the decay rate of minority carrier lifetime during the crystal growth process, which is beneficial to improving the efficiency of photovoltaic cells, but also the uniformity of phosphorus distribution in N-type single crystal silicon can be improved, so as to improve the resistivity uniformity of N-type single crystal silicon and slow down or avoid the fluctuation and decay of minority carrier lifetime during the crystal growth process.

[0067] The process control device includes a processor and a memory, and the construction module 10, the generation module 20 and the control module 30 are all stored in the memory as program units, and the processor executes the program units stored in the memory to implement corresponding functions. The modules are all located in the same processor; or, the modules are located in different processors in any combination.

[0068] The processor includes a kernel, which retrieves the corresponding program unit from the memory. One or more kernels can be set, and the problem that the electrical properties of the crystal cannot be guaranteed due to the Czochralski method single crystal silicon rod growth process in the prior art can be solved by adjusting the kernel parameters.

[0069] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM, and the memory includes at least one memory chip.

[0070] An embodiment of the present invention provides a computer-readable storage medium, the computer-readable storage medium including a stored program, wherein when the program is run, a control method for controlling a device where the computer-readable storage medium is located to execute a crystal pulling process.

[0071] Specifically, the control method of the crystal pulling process includes:

[0072] Step S201, constructing a transport numerical model of a target object in a single crystal furnace, wherein the target object includes at least one of an oxygen impurity and a phosphorus dopant, wherein the transport numerical model of the target object is used to at least reflect the distribution of the target object inside the single crystal furnace under different process conditions and magnetic field structures;

[0073] Specifically, the above-mentioned transport numerical model can be used to study the physical properties of the above-mentioned target objects in the melt and crystal at different stages of single crystal silicon growth under different process conditions and magnetic field structures, so as to develop transport control technology for target objects such as oxygen impurities and phosphorus dopants in magnetically controlled N-type single crystal silicon pulling growth.

[0074] Step S202, generating a plurality of characteristic parameters corresponding to the target object under a plurality of process conditions and a plurality of magnetic field structure parameters according to the transport numerical model of the target object, wherein the characteristic parameters are used to characterize the physical properties of the target object;

[0075] Specifically, according to the transport numerical model of the target object constructed, characteristic parameters of the target object under different process conditions and magnetic field structure parameters can be generated. These characteristic parameters can characterize the physical properties of the target object, including but not limited to the transport characteristics inside the silicon melt, the segregation characteristics at the crystal interface, the evaporation characteristics on the surface of the silicon melt, and the distribution laws along the radial and axial directions of the crystal. By comparing and analyzing these parameters, the consumption of oxygen impurities, phosphorus dopants and other target objects and the influence of their distribution in the crystal at different stages of single crystal silicon growth under the influence of different process conditions and magnetic field structure parameters can be studied.

[0076] Step S203, determining target process conditions and target magnetic field structure parameters according to multiple characteristic parameters, multiple process conditions and multiple magnetic field structure parameters, and controlling the single crystal furnace to perform a crystal pulling process under the target process conditions and target magnetic field structure parameters.

[0077] Specifically, based on the generated characteristic parameters, a set of optimal target process conditions and target magnetic field structure parameters can be determined in combination with historical experimental data. The selection of these parameters aims to improve the uniformity of the distribution of the target object in N-type single crystal silicon and avoid the influence of its uneven distribution on the minority carrier lifetime during the crystal growth process. Then, the determined target process conditions and magnetic field structure parameters are applied to the actual single crystal furnace control, and the single crystal furnace is ensured to operate under optimal conditions by adjusting parameters such as the crucible speed, crystal speed, hook-shaped magnetic field position and intensity. This control method can specifically solve the problems of uneven distribution of oxygen impurities and difficult control of phosphorus dopant transport in the existing process, thereby significantly improving the quality of Czochralski single crystal silicon rods.

[0078] An embodiment of the present invention provides a crystal pulling system, which includes a single crystal furnace, a processor, a memory, and a program stored in the memory and executable on the processor. When the processor executes the program, at least the following steps are implemented: constructing a transport numerical model of a target object in the single crystal furnace, the target object including at least one of oxygen impurities and phosphorus dopants, wherein the transport numerical model of the target object is used to at least reflect the distribution of the target object inside the single crystal furnace under different process conditions and magnetic field structures; generating multiple characteristic parameters corresponding to the target object under multiple process conditions and multiple magnetic field structure parameters according to the transport numerical model of the target object, wherein the characteristic parameters are used to characterize the physical properties of the target object; and selecting target process conditions and target magnetic field structure parameters from multiple process conditions and multiple magnetic field structure parameters according to the multiple characteristic parameters to control the single crystal furnace to perform a crystal pulling process under the target process conditions and target magnetic field structure parameters.

[0079] The present application also provides a computer program product, which, when executed on a data processing device, is suitable for executing a program that initializes at least the following method steps: constructing a transport numerical model of a target object in a single crystal furnace, the target object including at least one of oxygen impurities and phosphorus dopants, wherein the transport numerical model of the target object is used to at least reflect the distribution of the target object inside the single crystal furnace under different process conditions and magnetic field structures; based on the transport numerical model of the target object, generating multiple characteristic parameters corresponding to the target object under multiple process conditions and multiple magnetic field structure parameters, wherein the characteristic parameters are used to characterize the physical properties of the target object; based on the multiple characteristic parameters, selecting target process conditions and target magnetic field structure parameters from multiple process conditions and multiple magnetic field structure parameters to control the single crystal furnace to perform a crystal pulling process under the target process conditions and target magnetic field structure parameters.

[0080] Obviously, those skilled in the art should understand that the above modules or steps of the present invention can be implemented by a general computing device, they can be concentrated on a single computing device, or distributed on a network composed of multiple computing devices, they can be implemented by a program code executable by a computing device, so that they can be stored in a storage device and executed by the computing device, and in some cases, the steps shown or described can be executed in a different order than here, or they can be made into individual integrated circuit modules, or multiple modules or steps therein can be made into a single integrated circuit module for implementation. Thus, the present invention is not limited to any specific combination of hardware and software.

[0081] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0082] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1A device that provides the functions specified in a block or multiple blocks.

[0083] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0084] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0085] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0086] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. The memory is an example of a computer-readable medium.

[0087] Computer readable media include permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. Information can be computer readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, magnetic tape disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer readable media does not include temporary computer readable media (transitory media), such as modulated data signals and carrier waves.

[0088] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0089] From the above description, it can be seen that the above embodiments of the present application achieve the following technical effects:

[0090] 1) In the control method of the crystal pulling process of the embodiment of the present application, a transport numerical model of target objects such as oxygen impurities and phosphorus dopants is established to at least reflect the distribution of the target objects in the single crystal furnace under different process conditions and magnetic field structures, and based on the above transport numerical model, the physical properties of the above target objects in the melt and crystal at different stages of single crystal silicon growth under different process conditions and magnetic field structures are studied, so as to develop a transport control technology for target objects such as oxygen impurities and phosphorus dopants in magnetically controlled N-type single crystal silicon pulling growth, and then through process parameter optimization and magnetic field structure matching, not only can the reduction and uniform distribution of oxygen impurity concentration in the crystal be achieved, so as to reduce the decay rate of minority carrier lifetime during crystal growth, which is beneficial to improve the efficiency of photovoltaic cells, but also the uniformity of phosphorus distribution in N-type single crystal silicon can be improved, so as to improve the resistivity uniformity of N-type single crystal silicon and slow down or avoid the fluctuation and attenuation of minority carrier lifetime during crystal growth.

[0091] 2) The embodiment of the present application can verify whether the adjusted magnetic field structure parameters and process conditions can indeed improve the distribution uniformity of target objects such as oxygen impurities and phosphorus elements in N-type single crystal silicon through continuous production data collection and analysis.

[0092] 3) The embodiment of the present application can effectively utilize the hook-shaped magnetic field to improve the distribution uniformity of target objects such as oxygen impurities and phosphorus elements in N-type single crystal silicon, reduce the impact of uneven distribution on the minority carrier lifetime during the crystal growth process, and help improve the efficiency of photovoltaic cells.

[0093] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A control method for a crystal pulling process, characterized in that: include: Constructing a transport numerical model of a target object in a single crystal furnace, wherein the target object includes at least one of an oxygen impurity and a phosphorus dopant, wherein the transport numerical model of the target object is used to at least reflect the distribution of the target object inside the single crystal furnace under different process conditions and magnetic field structures; According to the transport numerical model of the target object, a plurality of characteristic parameters corresponding to the target object under a plurality of process conditions and a plurality of magnetic field structure parameters are generated, wherein the characteristic parameters are used to characterize the physical properties of the target object; According to the multiple characteristic parameters, target process conditions and target magnetic field structure parameters are screened from the multiple process conditions and the multiple magnetic field structure parameters to control the single crystal furnace to perform a crystal pulling process under the target process conditions and the target magnetic field structure parameters.

2. The control method according to claim 1, characterized in that: The target object includes oxygen impurities, and the construction of a transport numerical model of the target object in the single crystal furnace includes: According to a plurality of first historical experimental data under a plurality of process conditions and a plurality of magnetic field structure parameters and non-equilibrium molecular dynamics theory, a first theoretical relationship of the oxygen dissolution rate at the contact surface between the crucible and the silicon melt in the single crystal furnace under different process conditions and magnetic field structures is established, wherein the plurality of first historical experimental data include: the oxygen dissolution rate in the single crystal furnace and the oxygen concentration in the single crystal furnace; According to the first theoretical relationship, a transport numerical model of the oxygen impurities is constructed.

3. The control method according to claim 1, characterized in that: The target object includes a phosphorus dopant, and the step of constructing a transport numerical model of the target object in the single crystal furnace includes: A transport numerical model of the phosphorus dopant is constructed based on multiple second historical experimental data under multiple process conditions and multiple magnetic field structure parameters, wherein the multiple second historical experimental data include: the phosphorus dopant concentration in the single crystal furnace, and the resistivity of the single crystal silicon prepared by the single crystal furnace.

4. The control method according to claim 1, characterized in that: The step of generating a plurality of characteristic parameters corresponding to the target object under a plurality of process conditions and a plurality of magnetic field structure parameters according to the transport numerical model of the target object comprises: Calculation is performed according to the transport numerical model of the target object to obtain calculation results corresponding to multiple melt systems, wherein the calculation results include a dynamic relationship between an input set and an output set of the transport numerical model, and the dynamic relationship is used to reflect the physical properties corresponding to the multiple melt systems, any two of the melt systems have different dynamic properties, and the multiple melt systems correspond to multiple process conditions and multiple magnetic field structure parameters, respectively, wherein: In the case where the target object includes oxygen impurities, the physical properties include at least one of the following: occurrence characteristics of oxygen impurities in raw materials, dissolution characteristics of oxygen impurities on the crucible wall, transport characteristics of oxygen impurities in the silicon melt, segregation characteristics of oxygen impurities at the crystal interface, evaporation characteristics of oxygen impurities on the melt surface, and distribution laws of oxygen impurities along the radial and axial directions of the crystal; In the case where the target object includes a phosphorus dopant, the physical property includes at least one of the following: a transport property of the phosphorus dopant in a silicon melt, a segregation property of the phosphorus dopant at a crystal interface, an evaporation property of the phosphorus dopant on a silicon melt surface, and a distribution law of the phosphorus dopant along a radial direction and an axial direction of the crystal; According to the calculation results, a plurality of preset process conditions and a plurality of preset magnetic field structure parameters, a plurality of characteristic parameters respectively corresponding to the plurality of melt systems are determined.

5. The control method according to claim 4, characterized in that: Determining a plurality of characteristic parameters corresponding to a plurality of melt systems according to the calculation results, a plurality of preset process conditions and a plurality of preset magnetic field structure parameters includes: According to the calculation results, multiple preset rotational speeds and multiple preset hook-shaped magnetic field structure parameters, characteristic parameters corresponding to multiple melt systems are obtained, wherein the preset rotational speed includes at least: the crucible rotational speed of the single crystal furnace, and the crystal rotational speed of the single crystal furnace, the preset hook-shaped magnetic field structure parameters include at least: the position and intensity of the hook-shaped magnetic field, and the characteristic parameters include at least one of the following: the concentration distribution of the oxygen impurities, the crystal growth rate in the single crystal furnace, and the temperature distribution in the single crystal furnace.

6. The control method according to any one of claims 1 to 5, characterized in that: The step of selecting target process conditions and target magnetic field structure parameters from the plurality of process conditions and the plurality of magnetic field structure parameters according to the plurality of characteristic parameters comprises: Determining whether the plurality of characteristic parameters meet corresponding preset conditions; When a first target characteristic parameter among the plurality of characteristic parameters satisfies a target preset condition, the process conditions and the magnetic field structure parameters corresponding to the first target characteristic parameter are determined as target process conditions and target magnetic field structure parameters.

7. The control method according to claim 6, characterized in that: Also includes: Adjustment step: when the first target characteristic parameter does not meet the target preset condition, output an adjustment signal to the single crystal furnace to adjust the process conditions and the magnetic field structure parameters corresponding to the first target characteristic parameter; Determining step: re-determining updated first target characteristic parameters corresponding to the target object under the adjusted process conditions and / or magnetic field structure parameters according to the transport numerical model of the target object; Determination step: determining whether the first target characteristic parameter meets the target preset condition; In the case that the first target characteristic parameter does not satisfy the target preset condition, the adjusting step, the determining step and the judging step are repeatedly performed until the first target characteristic parameter satisfies the target preset condition and then stops.

8. The control method according to claim 7, characterized in that: When the single crystal furnace receives the adjustment signal, the single crystal silicon growth is performed using the adjusted process conditions and / or magnetic field structure parameters, and the determining step includes: generating, according to the transport numerical model of the target object, a second target characteristic parameter corresponding to the target object under the adjusted process conditions and / or magnetic field structure parameters, wherein the second target characteristic parameter is a characteristic parameter different from the first target characteristic parameter among the plurality of characteristic parameters; Acquiring target experimental data of the single crystal silicon growth, wherein the target experimental data and the second target characteristic parameter have the same characteristic type; Determine whether the difference between the second target characteristic parameter and the experimental data satisfies a preset difference; When the preset difference is met, the second target characteristic parameter is determined as the updated first target characteristic parameter.

9. A process control device for a single crystal silicon rod, characterized in that: include: A construction module, used to construct a transport numerical model of a target object in a single crystal furnace, wherein the target object includes at least one of an oxygen impurity and a phosphorus dopant, wherein the transport numerical model of the target object is used to at least reflect the distribution of the target object inside the single crystal furnace under different process conditions and magnetic field structures; A generating module, configured to generate, according to a transport numerical model of the target object, a plurality of characteristic parameters corresponding to the target object under a plurality of process conditions and a plurality of magnetic field structure parameters, wherein the characteristic parameters are used to characterize the physical properties of the target object; A control module is used to select target process conditions and target magnetic field structure parameters from the multiple process conditions and the multiple magnetic field structure parameters according to the multiple characteristic parameters, so as to control the single crystal furnace to perform a crystal pulling process under the target process conditions and the target magnetic field structure parameters.

10. A crystal pulling system, characterized in that: include: A single crystal furnace, one or more processors, a memory, and one or more programs, wherein the one or more processors are electrically connected to the single crystal furnace, the one or more programs are stored in the memory and are configured to be executed by the one or more processors, and the one or more programs include a control method for executing the crystal pulling process described in any one of claims 1 to 8.

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