Method and device for controlling resistivity of silicon single crystal rod and electronic equipment

Abstract

The invention provides a method and a device for controlling the resistivity of a silicon single crystal rod, and electronic equipment. The method comprises the following steps: acquiring a plurality of evaporation characteristic parameters, wherein the evaporation characteristic parameters are evaporation characteristics of a dopant under different crucible retention rates before a historical seeding step; according to the multiple evaporation characteristic parameters, the target crucible retention rate, the geometric parameters of the crucible and the preset content ratio, the target evaporation coefficient of the dopant before the current seeding step is determined, the target crucible retention rate is the crucible retention rate before the current seeding step, and the preset content ratio is the ratio of the initial silicon raw material content to the initial dopant content in the crucible; the evaporation coefficient represents the evaporation difficulty degree of the dopant under the corresponding crucible retention rate; according to the target evaporation coefficient, the compensation resistance of the head of the single crystal silicon rod is determined, the target compensation resistance is obtained, and the compensation resistance is the difference between the actual resistance and the expected resistance of the head of the single crystal silicon rod; and according to the target compensation resistance, determining a target addition amount of a dopant, and at least adding the target addition amount of the dopant into the crucible.

Description

Technical Field

[0001] The present application relates to the technical field of single crystal preparation, and in particular to a method, device and electronic equipment for controlling the resistivity of a single crystal silicon rod. Background Art

[0002] At present, in the production process of CZ-type single crystal silicon, the doping amount of impurities in the crucible is calculated based on the impurity segregation coefficient. The actual resistivity of the head of the single crystal silicon rod obtained is significantly different from the designed resistivity, resulting in a large difference in the electrical properties between the head of the single crystal silicon rod and other positions. Summary of the invention

[0003] The main purpose of the present application is to provide a method, device and electronic equipment for controlling the resistivity of a single crystal silicon rod, so as to at least solve the problem in the prior art that the actual value of the head resistance of a CZ single crystal silicon rod deviates greatly from the designed value.

[0004] In order to achieve the above-mentioned purpose, according to one aspect of the present application, a method for controlling the resistivity of a single crystal silicon rod is provided, comprising: obtaining a plurality of evaporation characteristic parameters, wherein the evaporation characteristic parameters are evaporation characteristics of a dopant at different crucible retention rates before a historical seeding step, wherein the crucible retention rate is a ratio of the amount of remaining material in the crucible to the initial charge amount in the crucible, and the evaporation characteristic is a parameter characterizing the characteristics affected by the crucible retention rate during the evaporation process; determining the evaporation coefficient of the dopant before the current seeding step according to the plurality of evaporation characteristic parameters, a target crucible retention rate, geometric parameters of the crucible, and a predetermined content ratio, to obtain to a target evaporation coefficient, the target crucible retention rate is the crucible retention rate before the current seeding step, the predetermined content ratio is the ratio of the initial silicon raw material content to the initial dopant content in the crucible, and the evaporation coefficient characterizes the ease of evaporation of the dopant at the corresponding crucible retention rate; according to the target evaporation coefficient, the compensation resistance of the single crystal silicon rod head is determined to obtain a target compensation resistance, the compensation resistance is the difference between the actual resistance of the single crystal silicon rod head and the expected resistance; according to the target compensation resistance, the target addition amount of the dopant is determined, and at least the target addition amount of the dopant is added to the crucible.

[0005] Optionally, obtaining a plurality of evaporation characteristic parameters includes: establishing a kinetic equation C(t)=C0e that reflects the relationship between the evaporation rate of the dopant and the content of the dopant in the crucible before the historical seeding step: -kt, wherein C(t) is the content of the dopant in the crucible heated to time t before the historical seeding step, C0 is the content of the dopant in the crucible before heating, e is a natural constant, k is an evaporation rate constant of the dopant, and t is a time; obtaining the remaining content of the dopant in the crucible corresponding to the crucible retention rate and the initial content of the dopant, and determining the evaporation rate constant corresponding to the crucible retention rate based on the remaining content, the initial content and the kinetic equation, and obtaining the evaporation characteristic parameter corresponding to the crucible retention rate.

[0006] Optionally, according to a plurality of the evaporation characteristic parameters, the target crucible retention rate, the geometric parameters of the crucible and the predetermined content ratio, the evaporation coefficient of the dopant before the current seeding step is determined to obtain a target evaporation coefficient, including: according to a plurality of the evaporation characteristic parameters, determining the evaporation characteristic parameters corresponding to the target crucible retention rate as the target evaporation characteristic parameters; according to the geometric parameters of the crucible, determining the lateral area to volume ratio of the crucible; according to the target crucible retention rate, the target evaporation characteristic parameters, the lateral area to volume ratio and the predetermined content ratio, determining the target evaporation coefficient as α=kRGS, wherein α is the target evaporation coefficient, k is the evaporation rate constant, R is the target crucible retention rate, G is the lateral area to volume ratio, and S is the predetermined content ratio.

[0007] Optionally, according to the target evaporation coefficient, the compensation resistance of the head of the single crystal silicon rod is determined to obtain the target compensation resistance, including: establishing a relationship model between the evaporation coefficient and the compensation resistance at different crucible retention rates; according to a plurality of the relationship models and the target crucible retention rate, determining the relationship model corresponding to the target crucible retention rate as the target relationship model; and inputting the target evaporation coefficient into the target relationship model to obtain the target compensation resistance.

[0008] Optionally, a relationship model between the evaporation coefficient and the compensation resistor at different crucible retention rates is established, including: obtaining multiple different evaporation coefficients corresponding to the same crucible retention rate, and obtaining the compensation resistors corresponding to multiple evaporation coefficients; performing nonlinear fitting on the multiple evaporation coefficients and the multiple compensation resistors to obtain the relationship model corresponding to the crucible retention rate.

[0009] Optionally, a target addition amount of a dopant is determined based on the target compensation resistance, including: determining a compensation amount of the dopant corresponding to the target compensation resistance based on the target compensation resistance; determining an initial addition amount of the dopant based on the target retention rate and the expected resistance; and determining the target addition amount as the sum of the compensation amount and the initial addition amount.

[0010] Optionally, adding at least the target amount of the dopant into the crucible includes: adding the target amount of the dopant into the crucible; and adjusting the heating temperature of the crucible after adding the dopant according to the target crucible retention rate, so that the heating temperature is within a preset temperature range corresponding to the target crucible retention rate.

[0011] Optionally, when the dopant is an N-type dopant, the dopant includes at least one of the following: phosphorus, antimony, arsenic, and bismuth; when the dopant is a P-type dopant, the dopant includes at least one of the following: boron, aluminum, gallium, indium, and thallium.

[0012] According to another aspect of the present application, a control device for the resistivity of a single crystal silicon rod is provided, comprising: an acquisition unit, for acquiring a plurality of evaporation characteristic parameters, wherein the evaporation characteristic parameters are evaporation characteristics of a dopant at different crucible retention rates before a historical seeding step, wherein the crucible retention rate is a ratio of the amount of remaining material in the crucible to the initial amount of material in the crucible, and wherein the evaporation characteristic characterizes a parameter of a characteristic affected by the crucible retention rate during an evaporation process; and a first determination unit, for determining an evaporation coefficient of the dopant before a current seeding step according to the plurality of evaporation characteristic parameters, a target crucible retention rate, geometric parameters of the crucible, and a predetermined content ratio, to obtain a target evaporation coefficient. The target crucible retention rate is the crucible retention rate before the current seeding step, the predetermined content ratio is the ratio of the initial silicon raw material content to the initial dopant content in the crucible, and the evaporation coefficient characterizes the ease of evaporation of the dopant at the corresponding crucible retention rate; a second determination unit is used to determine the compensation resistance of the single crystal silicon rod head according to the target evaporation coefficient to obtain the target compensation resistance, and the compensation resistance is the difference between the actual resistance of the single crystal silicon rod head and the expected resistance; an adding unit is used to determine the target addition amount of the dopant according to the target compensation resistance, and add at least the target addition amount of the dopant into the crucible.

[0013] According to another aspect of the present application, an electronic device is provided, comprising: one or more processors, a memory, and one or more programs, wherein 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 methods for executing any one of the described methods.

[0014] By applying the technical solution of the present application, the evaporation characteristic parameters of the dopant before the historical seeding step at multiple crucible retention rates are first obtained; then, the evaporation coefficient of the dopant before the current seeding step is determined according to the multiple evaporation characteristic parameters, the crucible retention rate before the current seeding step, the geometric parameters of the crucible, and the content ratio of the silicon raw material initially loaded in the crucible to the dopant; then, the compensation resistance of the head of the single crystal silicon rod is determined according to the evaporation coefficient; finally, the addition amount of the dopant is determined according to the compensation circuit, and the dopant is added to the crucible according to the addition amount, so as to compensate for the resistance of the head of the single crystal silicon rod, so that the actual resistance after compensation meets the requirement of the expected resistance, and the evaporation of the dopant at different crucible retention rates is fully considered, and the resistance change of the head of the single crystal silicon rod caused by the evaporation of the dopant can be accurately compensated, so that the resistance deviation of the head of the single crystal silicon rod is controlled within a very small range, which effectively solves the problem that the prior art does not fully consider the influence of factors such as the crucible retention rate on the evaporation of the dopant, resulting in a large deviation between the actual value of the head resistance of the CZ single crystal silicon rod and the design value. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] 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:

[0016] Figure 1 A hardware structure block diagram of a mobile terminal for executing a method for controlling the resistivity of a single crystal silicon rod provided in an embodiment of the present application is shown;

[0017] Figure 2 A schematic flow chart of a method for controlling the resistivity of a single crystal silicon rod provided in accordance with an embodiment of the present application is shown;

[0018] Figure 3 A control flow chart of the resistivity of a single crystal silicon rod provided according to an embodiment of the present application is shown;

[0019] Figure 4 A structural block diagram of a device for controlling the resistivity of a single crystal silicon rod provided according to an embodiment of the present application is shown.

[0020] The above drawings include the following reference numerals:

[0021] 102, processor; 104, memory; 106, transmission device; 108, input and output devices. DETAILED DESCRIPTION

[0022] 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.

[0023] 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.

[0024] 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.

[0025] As introduced in the background technology, in the prior art, the control method of the silicon rod head resistance is often relatively extensive, and only controls the content of dopants such as phosphorus based on empirical formulas or fixed doping ratios, without fully considering the dynamic effect of dopant evaporation on the resistivity of the silicon rod head during the silicon rod growth process, especially under different crucible retention rates. For example, the traditional method only adds a fixed amount of dopant to the silicon raw material, and then prepares the silicon rod according to the standard growth process, without targeted treatment of the dopant evaporation problem caused by changes in the crucible conditions (such as changes in the crucible retention rate) during the growth process, which makes the control accuracy of the silicon rod head resistance low, prone to large deviations, and difficult to meet the strict requirements of high-precision semiconductor manufacturing on the resistivity of the silicon rod head.

[0026] Therefore, there is a problem in the prior art that the actual value of the head resistance of the CZ-pulled single crystal silicon rod deviates greatly from the designed value. To solve the above technical problem, the embodiments of the present application provide a method, device and electronic device for controlling the resistivity of a single crystal silicon rod.

[0027] 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.

[0028] 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 1 is a hardware structure block diagram of a mobile terminal of a method for controlling the resistivity of a single crystal silicon rod according to an embodiment of the present invention. Figure 1As 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 are shown.

[0029] 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 resistivity control method of the single crystal silicon rod 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.

[0030] In this embodiment, a method for controlling the resistivity of a single crystal silicon rod 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 may be executed in an order different from that shown here.

[0031] Figure 2 1 is a flow chart of a method for controlling the resistivity of a single crystal silicon rod according to an embodiment of the present application. Figure 2 As shown, the method comprises the following steps:

[0032] Step S201, obtaining a plurality of evaporation characteristic parameters, the evaporation characteristic parameters being the evaporation characteristics of the dopant at different crucible retention rates before the historical seeding step, the crucible retention rate being the ratio of the amount of remaining material in the crucible to the initial amount of material in the crucible, the evaporation characteristic being a parameter characterizing the characteristics affected by the crucible retention rate during the evaporation process;

[0033] Specifically, a crucible retention rate corresponds to an evaporation characteristic parameter. The evaporation characteristic may include an evaporation rate constant. The amount of remaining material in the crucible is the amount of material in the crucible before the historical seeding step, and the material in the crucible includes silicon raw material and dopant.

[0034] Step S202, determining the evaporation coefficient of the dopant before the current seeding step according to a plurality of evaporation characteristic parameters, a target crucible retention rate, geometric parameters of the crucible, and a predetermined content ratio, to obtain a target evaporation coefficient, wherein the target crucible retention rate is the crucible retention rate before the current seeding step, the predetermined content ratio is the ratio of the initial silicon raw material content in the crucible to the initial dopant content, and the evaporation coefficient represents the ease of evaporation of the dopant at the corresponding crucible retention rate;

[0035] Specifically, the target crucible retention rate is the ratio of the amount of remaining material in the crucible before the current seeding step to the initial charge amount in the crucible. The initial silicon raw material content in the crucible is the silicon raw material content when charging in an empty crucible, and the initial dopant content in the crucible is the dopant content when charging in an empty crucible, that is, the predetermined content ratio is the ratio of the initial silicon raw material charge amount to the dopant charge amount in the crucible.

[0036] Step S203, determining the compensation resistance of the head of the single crystal silicon rod according to the target evaporation coefficient to obtain the target compensation resistance, where the compensation resistance is the difference between the actual resistance of the head of the single crystal silicon rod and the expected resistance;

[0037] Specifically, the head of the single crystal silicon rod refers to the part of the single crystal silicon rod connected to the seed crystal, and the single crystal silicon rod is obtained through the current seeding step and a series of subsequent steps. The above actual resistance is greater than the above expected resistance, and the actual resistance of the head of the single crystal silicon rod is reduced by increasing the amount of dopant added to make it close to the expected resistance.

[0038] Step S204, determining a target addition amount of the dopant according to the target compensation resistance, and adding at least the target addition amount of the dopant into the crucible.

[0039] Specifically, a target addition amount of dopant is added into the crucible before the current seeding step.

[0040] Through the above embodiment, the evaporation characteristic parameters of the dopant before the historical seeding step at multiple crucible retention rates are first obtained; then, the evaporation coefficient of the dopant before the current seeding step is determined according to the multiple evaporation characteristic parameters, the crucible retention rate before the current seeding step, the geometric parameters of the crucible, and the content ratio of the silicon raw material initially loaded in the crucible to the dopant; then, according to the evaporation coefficient, the compensation resistance of the head of the single crystal silicon rod is determined; finally, the addition amount of the dopant is determined according to the compensation circuit, and the dopant is added to the crucible according to the addition amount, so as to compensate for the resistance of the head of the single crystal silicon rod, so that the actual resistance after compensation meets the requirement of the expected resistance, and the evaporation of the dopant at different crucible retention rates is fully considered, and the resistance change of the head of the single crystal silicon rod caused by the evaporation of the dopant can be accurately compensated, so that the resistance deviation of the head of the single crystal silicon rod is controlled within a very small range, which effectively solves the problem that the influence of factors such as the crucible retention rate on the evaporation of the dopant is not fully considered in the prior art, resulting in a large deviation between the actual value of the head resistance of the CZ single crystal silicon rod and the design value.

[0041] In addition to adding a target amount of dopants into the crucible, silicon raw materials need to be added into the crucible for pulling the current single crystal silicon rod, wherein the amount of silicon raw materials added is smaller than the volume of the crucible.

[0042] In an optional scheme, multiple evaporation characteristic parameters are obtained, including: using a control variable method to obtain multiple crucible retention rate sample group data, each data includes the evaporation rate of the dopant and the corresponding crucible retention rate before the historical seeding step, and except for the evaporation rate and the crucible retention rate, other parameters of the multiple crucible retention rate sample groups are the same; based on the multiple data, nonlinear fitting is performed on the evaporation rate and the crucible retention rate to obtain the evaporation rate constant of the dopant at different crucible retention rates.

[0043] In another alternative, a plurality of evaporation characteristic parameters are obtained, including: establishing a kinetic equation C(t)=C0e that reflects the relationship between the evaporation rate of the dopant before the historical seeding step and the content of the dopant in the crucible. -kt, where C(t) is the content of the dopant in the crucible heated to time t before the historical seeding step, that is, C(t) is the remaining content of the dopant in the crucible after heating for (t-t0) time, t0 is the start time of heating, C0 is the content of the dopant in the crucible before heating, e is a natural constant, k is the evaporation rate constant of the dopant, and t is the time; the remaining content of the dopant in the crucible corresponding to the crucible retention rate and the initial content of the dopant are obtained, where the initial content of the dopant refers to the content of the dopant in the crucible before heating, and the evaporation rate constant corresponding to the crucible retention rate is determined according to the remaining content, the initial content and the kinetic equation, and the evaporation characteristic parameters corresponding to the crucible retention rate are obtained. The inventors found that the evaporation process of the dopant conforms to the first-order reaction kinetic equation, that is, the evaporation rate is proportional to the remaining dopant content in the crucible. Therefore, this embodiment establishes a kinetic equation between the evaporation rate and the dopant content in the crucible, and the equation includes the evaporation rate constant of the dopant. The dopant content in the crucible before and after heating is substituted into the kinetic equation to obtain the evaporation rate constant of the dopant at different crucible retention rates. This scheme provides a quantitative description and control means for the evaporation process of the dopant, so that in the direct pulling process where the dopant content needs to be precisely controlled, the evaporation of the dopant can be more accurately controlled to obtain the desired material properties; the evaporation behavior of the dopant at different crucible retention rates can be determined through the evaporation rate constant and the amount of dopant added can be controlled, thereby optimizing the production process of the single crystal silicon rod and further ensuring that the resistance of the head of the single crystal silicon rod finally obtained meets the design value requirements.

[0044] Specifically, a variety of analysis techniques can be used to monitor the change in the content of the dopant in the crucible. For example, spectral analysis technology can be used to perform spectral analysis on the gas above the crucible to determine the change in the intensity of the characteristic spectral lines of the dopant element, thereby indirectly inferring the evaporation amount of the dopant; or mass spectrometry technology can be used to directly measure the number of ions or molecules of the dopant evaporated into the gas phase, thereby calculating the evaporation amount of the dopant. The evaporation amount is measured at different time points, and as time goes by, the change data of the evaporation amount of the dopant over time is recorded, thereby calculating the evaporation rate.

[0045] In other optional schemes, the evaporation characteristic parameter includes an evaporation time constant, wherein the evaporation time constant is defined as C(t)=C0e -1 The time value at the time. Obtain multiple evaporation characteristic parameters, including: Establishing a kinetic equation C(t)=C0e that reflects the relationship between the evaporation rate of the dopant before the historical seeding step and the content of the dopant in the crucible -kt, wherein C(t) is the content of the dopant in the crucible heated to time t before the historical seeding step, C0 is the content of the dopant in the crucible before heating, e is a natural constant, k is the evaporation rate constant of the dopant, and t is the time; the remaining content of the dopant in the crucible corresponding to the crucible retention rate and the initial content of the dopant are obtained, and the evaporation rate constant corresponding to the crucible retention rate is determined based on the remaining content, the initial content and the kinetic equation; based on the evaporation rate constant, the evaporation time constant corresponding to the crucible retention rate is determined to be the inverse of the evaporation rate constant, and the evaporation characteristic parameters corresponding to the crucible retention rate are obtained.

[0046] Of course, in actual application, the evaporation characteristic parameters may include both the evaporation rate constant and the evaporation time constant.

[0047] In some embodiments, according to multiple evaporation characteristic parameters, target crucible retention rate, geometric parameters of the crucible and predetermined content ratio, the evaporation coefficient of the dopant before the current seeding step is determined to obtain the target evaporation coefficient, including: according to multiple evaporation characteristic parameters, the evaporation characteristic parameters corresponding to the target crucible retention rate are determined as the target evaporation characteristic parameters; according to the geometric parameters of the crucible, the side area volume ratio of the crucible is determined; according to the target crucible retention rate, the target evaporation characteristic parameters, the side area volume ratio and the predetermined content ratio, the target evaporation coefficient is determined as α=kRGS, wherein α is the target evaporation coefficient, k is the evaporation rate constant, R is the target crucible retention rate, G is the side area volume ratio, and S is the predetermined content ratio. In this embodiment, through the comprehensive consideration of multiple parameters such as evaporation characteristic parameters, crucible retention rate, geometric parameters of the crucible and predetermined content ratio, the evaporation coefficient of the dopant at the target crucible retention rate can be accurately determined, and the evaporation coefficient of the dopant under different crucible retention rates is quantified, which provides an accurate data basis for the subsequent determination of the compensation resistor based on the evaporation coefficient to achieve accurate compensation of the single crystal silicon rod head resistance.

[0048] Specifically, the process of determining the target evaporation characteristic parameter is to select the evaporation characteristic parameter corresponding to the same crucible retention rate as the target crucible retention rate from multiple evaporation characteristic parameters to obtain the target evaporation characteristic parameter. The target evaporation characteristic parameter is an evaporation rate constant.

[0049] In addition, when the evaporation characteristic parameters include the evaporation time constant, the target evaporation coefficient is determined as Here, τ is the evaporation time constant.

[0050] In actual application, the crucible is generally cylindrical, so the side area to volume ratio is Where r is the radius of the crucible and h is the height of the crucible.

[0051] According to some other embodiments of the present application, the compensation resistance of the head of the single crystal silicon rod is determined according to the target evaporation coefficient to obtain the target compensation resistance, including: establishing a relationship model between the evaporation coefficient and the compensation resistance at different crucible retention rates; determining the relationship model corresponding to the target crucible retention rate as the target relationship model according to multiple relationship models and the target crucible retention rate; inputting the target evaporation coefficient into the target relationship model to obtain the target compensation resistance. In this embodiment, a relationship between the evaporation coefficient and the compensation resistance of the head of the single crystal silicon rod is established based on the evaporation coefficient, so as to achieve accurate compensation of the head resistance of the single crystal silicon rod, greatly improving the accuracy and precision of the control of the head resistance of the single crystal silicon rod, and providing key technical support for the high-quality development of semiconductor silicon rod manufacturing. This control method can effectively reduce the problem of single crystal silicon rod head resistance deviation caused by the limitations of traditional methods, and further improve the consistency of the electrical performance of the single crystal silicon rod.

[0052] Specifically, one crucible retention rate corresponds to one relationship model, and a relationship model between the evaporation coefficient and the compensation resistance at different crucible retention rates can be established by means of data fitting or a neural network model.

[0053] In one embodiment, a relationship model between the evaporation coefficient and the compensation resistor at different crucible retention rates is established, including: obtaining multiple different evaporation coefficients corresponding to the same crucible retention rate, and obtaining compensation resistors corresponding to multiple evaporation coefficients; performing nonlinear fitting on multiple evaporation coefficients and multiple compensation resistors to obtain a relationship model corresponding to the crucible retention rate. This solution uses a nonlinear fitting method to establish a relationship model between the evaporation coefficient and the compensation resistor at different crucible retention rates, which can achieve accurate prediction of the compensation resistor of the head of the single crystal silicon rod. According to the prediction result, the resistance compensation of the head of the single crystal silicon rod can be performed, which can further improve the production quality of the head of the single crystal silicon rod during the direct pulling process.

[0054] Specifically, the compensation resistance can be obtained by measuring the difference between the actual head resistance of the single crystal silicon rod obtained by the existing method (i.e., the method of adding a fixed amount of dopant to the silicon raw material) and the expected head resistance. The actual head resistance can be measured by using a high-precision resistance measurement technology such as a four-probe method to obtain accurate resistance value data. Different evaporation coefficients corresponding to the same crucible retention rate can be achieved by changing the geometry of the crucible, the initial silicon raw material content in the crucible, and the initial dopant content in the crucible.

[0055] In order to further solve the problem of large deviation between the actual value and the design value of the head resistance of the CZ-pulled single crystal silicon rod in the prior art, in the present application, the target addition amount of the dopant is determined according to the target compensation resistance, including: determining the compensation amount of the dopant corresponding to the target compensation resistance according to the target compensation resistance; determining the initial addition amount of the dopant according to the target crumb retention rate and the expected resistance; determining the target addition amount as the sum of the compensation amount and the initial addition amount. In this way, the calculation accuracy of the dopant addition amount is improved, and the effect of controlling the resistance deviation of the head of the single crystal silicon rod within a very small range is further achieved, thereby further improving the accuracy of the head resistivity of the CZ-pulled single crystal silicon rod, and further ensuring that the actual value of the head resistance of the CZ-pulled single crystal silicon rod is substantially equal to its design value.

[0056] Exemplarily, adding at least a target amount of dopant to the crucible includes: adding a target amount of dopant to the crucible; adjusting the heating temperature of the crucible after adding the dopant according to the target crucible retention rate, so that the heating temperature is within a preset temperature range corresponding to the target crucible retention rate. In this embodiment, after adding the target amount of dopant to the crucible, the heating temperature of the crucible is adjusted to match the target crucible retention rate, ensuring that the silicon melt and the dopant in the crucible are uniformly heated, thereby maintaining a stable thermal field distribution during the CZ pulling process, and further ensuring accurate control of the resistance of the head of the single crystal silicon rod.

[0057] Optionally, when the dopant is an N-type dopant, the dopant includes at least one of the following: phosphorus, antimony, arsenic, bismuth; when the dopant is a P-type dopant, the dopant includes at least one of the following: boron, aluminum, gallium, indium, thallium. The above dopants are all volatile in a high temperature environment. The compensation measures based on their evaporation effect in this application can effectively avoid the resistivity deviation of the head of the single crystal silicon rod caused by the change of the crucible retention rate, thereby greatly improving the accuracy of the resistivity of the head of the single crystal silicon rod, ensuring that the electrical properties of the single crystal silicon rod meet the strict requirements of semiconductor manufacturing, and also providing a theoretical basis for further external field regulation of dopant segregation.

[0058] In order to enable those skilled in the art to more clearly understand the technical solution of the present application, the implementation process of the method for controlling the resistivity of a single crystal silicon rod of the present application will be described in detail below in conjunction with specific embodiments.

[0059] This embodiment relates to a specific method for controlling the resistivity of a single crystal silicon rod, and is described by taking the single crystal silicon rod as an N-type silicon rod and the dopant as phosphorus as an example. It should be noted that the method of the present application is not limited to the resistivity control of N-type single crystal silicon rods, and the method of the present application can also be applied to the resistivity control of P-type single crystal silicon rods; the method of the present application is not limited to the method in which the dopant is phosphorus, and the dopant can also be other dopants such as antimony, boron or aluminum. The solution of the present application is described below in conjunction with the technical problem.

[0060] At present, the doping elements of n-type CZ silicon are mostly phosphorus, which has a relatively small segregation coefficient (0.35) in silicon and a large saturated vapor pressure. Therefore, it is easily controlled by various factors such as volatilization, segregation, and melt flow during the directional solidification of polycrystalline silicon, which ultimately leads to its uneven distribution in the single crystal silicon, resulting in large differences in the electrical properties of single crystal silicon at different positions. Since the photoelectric conversion efficiency of the battery is closely related to the minority carrier lifetime, this also leads to the phenomenon that the conversion efficiency of n-type single crystal silicon batteries is unstable when single crystal silicon is prepared into batteries. The calculation of the doping amount is based only on the basic principle of segregation without considering the evaporation of impurities in the silicon melt, which often makes the simulated head resistance and the actual head resistance differ greatly, resulting in resistance misses, which in turn affects the quality of the single crystal silicon rod.

[0061] like Figure 3 As shown, the present application calculates the evaporation rate constant and evaporation time constant of impurity phosphorus corresponding to different crucible retention rates based on the evaporation effect of phosphorus, and then obtains the evaporation coefficient of impurity phosphorus corresponding to different crucible retention rates. Then, according to the relationship model between the evaporation coefficient and the compensation resistance of the head of the single crystal silicon rod at different crucible retention rates, the compensation resistance is determined, thereby controlling the amount of impurity phosphorus added in the crucible, so as to achieve the purpose of more accurately controlling the accuracy of the resistivity of the silicon rod head.

[0062] The specific calculation process of the evaporation coefficient is as follows:

[0063] (1) Experimental preparation:

[0064] a. Experimental equipment and material preparation:

[0065] Prepare multiple crucibles of the same specifications, which must have high-precision quality and size consistency to ensure consistency of experimental conditions. At the same time, prepare high-purity silicon raw materials and dopants containing phosphorus impurities and high-precision sensors for measuring parameters such as temperature and pressure;

[0066] Build an experimental furnace that can precisely control the temperature, pressure and atmosphere. The furnace should be able to simulate the thermal field conditions during the actual silicon rod growth process and have an observation window or internal detection device to monitor the situation inside the crucible in real time.

[0067] b. Sample preparation:

[0068] Silicon raw material and phosphorus-containing dopant are added to each crucible in a predetermined ratio to obtain samples with different initial phosphorus concentrations. At the same time, different crucible retention rate conditions are set by changing the loading amount of the crucible, and multiple repeated samples are set for each crucible retention rate condition.

[0069] (2) Determination of evaporation rate constant and evaporation time constant during the experiment:

[0070] a. Heating and temperature control:

[0071] Place the crucible containing the sample into the experimental furnace and raise the furnace temperature to the typical temperature range of silicon rod growth at a predetermined heating rate. During the heating process, continuously monitor and record the changes in temperature, pressure, and atmosphere composition in the experimental furnace;

[0072] After reaching the target temperature, keep the temperature stable and start timing, which is the start time of the experiment;

[0073] b. Phosphorus evaporation monitoring:

[0074] A variety of analytical techniques are used to monitor changes in the content of phosphorus impurities in the crucible. For example, spectral analysis can be used to perform spectral analysis on the gas above the crucible to determine the changes in the intensity of the characteristic spectral lines of the phosphorus element, thereby indirectly inferring the amount of phosphorus evaporated. Alternatively, mass spectrometry can be used to directly measure the number of phosphorus ions or molecules evaporated into the gas phase;

[0075] Measurements were taken at different time points, and the data on the change in phosphorus evaporation over time were recorded. For each sample group with different crucible retention rates, the experiment was repeated several times to obtain reliable data;

[0076] c. Calculation of evaporation rate constant and evaporation time constant:

[0077] The evaporation process of phosphorus conforms to the first-order reaction kinetic equation, that is, the evaporation rate is proportional to the concentration of residual phosphorus in the crucible. Let C(t) be the concentration of phosphorus in the crucible when heated to time t, and k be the evaporation rate constant. The evaporation rate V can be expressed as: V = -dC(t) / dt = kC(t). Solving this differential equation, we get the reaction kinetic equation C(t) = C0e -kt , C0 is the initial concentration of phosphorus in the crucible before heating. The phosphorus evaporation amount-time data obtained are fitted according to the reaction kinetic equation, and the evaporation rate constant of phosphorus impurities under different crucible retention rates can be obtained;

[0078] At the same time, by observing the characteristics of the phosphorus evaporation curve over time, it is determined that the stable evaporation state (i.e., satisfying C(t) = C0e -1 ) is the evaporation time constant, which is 1 / k. These evaporation rate constants and the corresponding evaporation time constants are the key parameters to describe the evaporation characteristics of phosphorus under different retention rates.

[0079] (3) Calculate the evaporation coefficient:

[0080] According to the obtained evaporation rate constant and / or evaporation time constant, combined with the initial concentration of silicon and phosphorus in the crucible, the geometric parameters of the crucible, and the crucible retention rate and other parameters, the calculation formula of the phosphorus evaporation coefficient α=kRGS is established through theoretical deduction. The specific forms of G and S here need to be determined according to the actual geometric shape of the crucible and the initial concentration of silicon and phosphorus. For example, if the crucible is cylindrical, G may be related to the radius r and height h of the cylinder, such as G=2πrh / V (V is the total volume of the crucible), and S can be expressed as the ratio of the initial concentrations of silicon and phosphorus. The evaporation coefficient comprehensively considers the comprehensive influence of multiple complex factors such as crucible retention rate, crucible geometry, temperature, pressure, etc. on phosphorus evaporation, which can reflect the difficulty of phosphorus evaporation at a specific crucible retention rate and the trend of evaporation over time. Using the above formula, the evaporation coefficient of phosphorus at different crucible retention rates is calculated. These evaporation coefficients will serve as an important basis for the subsequent control of the target resistance value of the head.

[0081] The calculation process of compensation resistance is as follows:

[0082] a. Establish the relationship model between phosphorus evaporation coefficient and head compensation resistance:

[0083] Through a large number of experimental and theoretical studies, considering factors such as the electrical properties of silicon rods, the doping behavior of phosphorus in silicon, and the special physical structure of the silicon rod head area, a quantitative relationship model between the phosphorus evaporation coefficient and the compensation resistance of the single crystal silicon rod head under different crucible retention rates was established.

[0084] In the process of model building, the resistance of the silicon rod head grown under different evaporation coefficients was measured, and high-precision resistance measurement technology such as the four-probe method was used to obtain accurate resistance value data. Through data analysis and fitting, the functional relationship between the phosphorus evaporation coefficient and the head compensation resistance was determined.

[0085] b. Resistance compensation control:

[0086] Substitute the evaporation coefficient into the relationship model of phosphorus evaporation coefficient-head compensation resistance to obtain the resistance value that needs to be compensated.

[0087] According to the calculated compensation resistance value, the amount of phosphorus dopant added is determined, and the precise control of the silicon rod head resistance is achieved by adjusting the process parameters, including adding the above amount of dopant, controlling the thermal field distribution, and controlling the silicon rod growth rate. During the growth process, the change of the silicon rod head resistance is continuously monitored, and the process parameters are adjusted in time according to the deviation between the actual measured value and the target resistance value to ensure that the head resistance is always kept within the predetermined accuracy range.

[0088] A specific application of using the resistivity control method of the single crystal silicon rod of the present application to compensate the resistivity of the head of the single crystal silicon rod is as follows:

[0089] Quartz crucibles of different sizes were used, with crucible radius of 10 cm, 12 cm and 15 cm, and height of 30 cm. The initial silicon raw material purity was 99.999%, and the concentration of phosphorus dopant was set to three different levels, namely 1×10 15 cm -3 , 5×10 15 cm -3 and 1×10 17 cm -3 .

[0090] The crucible retention rate was controlled by changing the raw material charge amount in each experiment, and was set to 0.6, 0.7 and 0.8 respectively. The experimental temperature was controlled at 1420℃, which is a typical temperature for the growth of single crystal silicon rods, and the pressure in the furnace was kept at 1 standard atmosphere during the entire experiment.

[0091] First, the phosphorus evaporation amount was determined by monitoring the change in the phosphorus content in the gas above the crucible through spectral analysis technology. The phosphorus evaporation data was recorded at different time points, and it was found that the change in phosphorus evaporation over time basically conformed to the first-order reaction kinetic model.

[0092] For a radius of 10 cm and an initial phosphorus concentration of 1×10 15 cm -3 , the crucible with a crucible retention rate of 0.6, the evaporation rate constant k = 0.01s -1 Assuming the crucible is a cylindrical crucible, consider the crucible volume V = πr 2 h, (Here the shape details of the bottom of the crucible are ignored), then G = 2 / 10 = 0.2. Initial silicon-phosphorus concentration ratio S = C Si0 / C P0 , assuming that the initial concentration of silicon is high (compared to phosphorus), approximately 10 23 cm -3 , then S = 10 23 / (1×10 16 )=10 7 .

[0093] According to the evaporation coefficient formula α=kRGS, the evaporation coefficient α=0.01×0.6×0.2×10 7 =1.2×10 4 .

[0094] By calculating the evaporation coefficient under different experimental conditions, the relationship between the evaporation coefficient and the compensation resistance value of the silicon rod head was established. It was found that when the evaporation coefficient is =1.2×10 4When the silicon rod is made of silicon dioxide, the compensation resistance value of the silicon rod head is about 0.5Ω·cm. By adjusting the phosphorus doping amount and other process parameters, the error between the actual resistance of the silicon rod head and the expected resistance is successfully controlled within ±5%.

[0095] This application scheme derives the compensation head target resistance value by calculating the evaporation coefficient of phosphorus, thereby achieving more accurate control of the head resistance, and has the following significant technical effects:

[0096] (1) Improve resistance control accuracy: Traditional methods have large errors when controlling the resistance of the silicon rod head, while the present application fully considers the evaporation of phosphorus at different crucible retention rates. By accurately calculating the evaporation coefficient, the resistance change caused by phosphorus evaporation can be accurately compensated. This greatly improves the control accuracy of the resistance at the silicon rod head, and can control the deviation of the resistance value within a very small range, better meeting the strict requirements of high-precision semiconductor manufacturing on the electrical properties of silicon rods;

[0097] (2) Enhance product consistency: In the process of large-scale production of silicon rods, the fluctuations in various process conditions, especially the changes in the crucible retention rate, can easily lead to inconsistent resistance at the head of the silicon rods. The technical solution of the present application effectively overcomes this problem. By calculating the phosphorus evaporation coefficient and the corresponding resistance compensation, the resistance at the head of the silicon rods in different batches or even in different positions of the same batch can maintain a high degree of consistency, thereby improving the stability of product quality and reducing product performance fluctuations caused by resistance differences;

[0098] (3) Optimize process parameter adjustment: Based on the relationship between the phosphorus evaporation coefficient and the head target resistance value, producers can adjust process parameters more scientifically. During the silicon rod growth process, the doping amount, temperature, growth rate and other process parameters can be adjusted quickly and accurately according to the real-time monitoring of the crucible retention rate and other parameter changes, so as to achieve dynamic optimization control of the head resistance. This dynamic adjustment capability not only improves production efficiency, but also reduces the waste of resources caused by trial and error adjustment of process parameters;

[0099] (4) Expanding the scope of application: The technical effect of accurately controlling the resistance of the silicon rod head makes the silicon rod advantageous in a wider range of semiconductor application fields. Whether it is for integrated circuit manufacturing with extremely high resistance precision requirements, or for other electronic equipment fields that require the stability of the electrical properties of silicon materials, the silicon rods produced by this application solution can better meet their needs, thereby broadening the market application prospects of silicon rod products.

[0100] It should be noted that the steps shown in the flowcharts of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and that, although a logical order is shown in the flowcharts, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0101] The embodiment of the present application also provides a control device for the resistivity of a single crystal silicon rod. It should be noted that the control device for the resistivity of a single crystal silicon rod in the embodiment of the present application can be used to execute the control method for the resistivity of a single crystal silicon rod provided in the embodiment of the present application. The device is used to implement the above-mentioned embodiments and preferred implementation modes, and those that have been described will not be repeated. 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.

[0102] The resistivity control device of a single crystal silicon rod provided in an embodiment of the present application is introduced below.

[0103] Figure 4 Schematic diagram of a device for controlling the resistivity of a single crystal silicon rod according to an embodiment of the present application. Figure 4 As shown, the device comprises:

[0104] An acquisition unit 10 is used to acquire a plurality of evaporation characteristic parameters, wherein the evaporation characteristic parameters are evaporation characteristics of the dopant at different crucible retention rates before the historical seeding step, wherein the crucible retention rate is a ratio of the amount of remaining material in the crucible to the initial amount of material in the crucible, and the evaporation characteristic is a parameter characterizing the characteristics affected by the crucible retention rate during the evaporation process;

[0105] Specifically, a crucible retention rate corresponds to an evaporation characteristic parameter. The evaporation characteristic may include an evaporation rate constant. The amount of remaining material in the crucible is the amount of material in the crucible before the historical seeding step, and the material in the crucible includes silicon raw material and dopant.

[0106] The first determination unit 20 is used to determine the evaporation coefficient of the dopant before the current seeding step according to a plurality of evaporation characteristic parameters, a target crucible retention rate, geometric parameters of the crucible, and a predetermined content ratio, and obtain a target evaporation coefficient, wherein the target crucible retention rate is the crucible retention rate before the current seeding step, the predetermined content ratio is the ratio of the initial silicon raw material content to the initial dopant content in the crucible, and the evaporation coefficient represents the ease of evaporation of the dopant at the corresponding crucible retention rate;

[0107] Specifically, the target crucible retention rate is the ratio of the amount of remaining material in the crucible before the current seeding step to the initial charge amount in the crucible. The initial silicon raw material content in the crucible is the silicon raw material content when charging in an empty crucible, and the initial dopant content in the crucible is the dopant content when charging in an empty crucible, that is, the predetermined content ratio is the ratio of the initial silicon raw material charge amount to the dopant charge amount in the crucible.

[0108] A second determination unit 30 is used to determine the compensation resistance of the single crystal silicon rod head according to the target evaporation coefficient to obtain the target compensation resistance, where the compensation resistance is the difference between the actual resistance of the single crystal silicon rod head and the expected resistance;

[0109] Specifically, the head of the single crystal silicon rod refers to the part of the single crystal silicon rod connected to the seed crystal, and the single crystal silicon rod is obtained through the current seeding step and a series of subsequent steps. The above actual resistance is greater than the above expected resistance, and the actual resistance of the head of the single crystal silicon rod is reduced by increasing the amount of dopant added to make it close to the expected resistance.

[0110] The adding unit 40 is used to determine a target addition amount of the dopant according to a target compensation resistance, and to add at least the target addition amount of the dopant into the crucible.

[0111] Specifically, a target addition amount of dopant is added into the crucible before the current seeding step.

[0112] Through the above embodiment, the evaporation characteristic parameters of the dopant before the historical seeding step at multiple crucible retention rates are obtained by the acquisition unit; the evaporation coefficient of the dopant before the current seeding step is determined by the first determination unit according to the multiple evaporation characteristic parameters, the crucible retention rate before the current seeding step, the geometric parameters of the crucible, and the content ratio of the silicon raw material initially loaded in the crucible to the dopant; the compensation resistance of the head of the single crystal silicon rod is determined by the second determination unit according to the evaporation coefficient; the addition amount of the dopant is determined by the adding unit according to the compensation circuit, and the dopant is added to the crucible according to the addition amount, so as to compensate for the resistance of the head of the single crystal silicon rod, so that the actual resistance after compensation meets the requirement of the expected resistance, fully considers the evaporation of the dopant at different crucible retention rates, can accurately compensate for the resistance change of the head of the single crystal silicon rod caused by the evaporation of the dopant, so as to control the resistance deviation of the head of the single crystal silicon rod within a very small range, and effectively solves the problem that the influence of factors such as the crucible retention rate on the evaporation of the dopant is not fully considered in the prior art, resulting in a large deviation between the actual value of the head resistance of the CZ single crystal silicon rod and the design value.

[0113] In addition to adding a target amount of dopants into the crucible, silicon raw materials need to be added into the crucible for pulling the current single crystal silicon rod, wherein the amount of silicon raw materials added is smaller than the volume of the crucible.

[0114] In an optional scheme, the acquisition unit includes: a first acquisition module, which is used to adopt a control variable method to acquire multiple crucible retention rate sample group data, each data includes the evaporation rate of the dopant and the corresponding crucible retention rate before the historical seeding step, and except for the evaporation rate and the crucible retention rate, other parameters of the multiple crucible retention rate sample groups are the same; a fitting module, which is used to perform nonlinear fitting on the evaporation rate and the crucible retention rate according to the multiple data to obtain the evaporation rate constant of the dopant at different crucible retention rates.

[0115] In another optional solution, the acquisition unit includes: a first establishment module for establishing a kinetic equation C(t)=C0e reflecting the relationship between the evaporation rate of the dopant and the content of the dopant in the crucible before the historical seeding step -kt , wherein C(t) is the content of the dopant in the crucible heated to time t before the historical seeding step, that is, C(t) is the remaining content of the dopant in the crucible after heating for (t-t0) time, t0 is the start time of heating, C0 is the content of the dopant in the crucible before heating, e is a natural constant, k is the evaporation rate constant of the dopant, and t is the time; the second acquisition module is used to obtain the remaining content of the dopant in the crucible corresponding to the crucible retention rate and the initial content of the dopant, wherein the initial content of the dopant refers to the content of the dopant in the crucible before heating, and according to the remaining content, the initial content and the kinetic equation, the evaporation rate constant corresponding to the crucible retention rate is determined to obtain the evaporation characteristic parameters corresponding to the crucible retention rate. The inventors found that the evaporation process of the dopant conforms to the first-order reaction kinetic equation, that is, the evaporation rate is proportional to the remaining dopant content in the crucible. Therefore, this embodiment establishes a kinetic equation between the evaporation rate and the dopant content in the crucible, and the equation includes the evaporation rate constant of the dopant. The dopant content in the crucible before and after heating is substituted into the kinetic equation to obtain the evaporation rate constant of the dopant at different crucible retention rates. This scheme provides a quantitative description and control means for the evaporation process of the dopant, so that in the direct pulling process where the dopant content needs to be precisely controlled, the evaporation of the dopant can be more accurately controlled to obtain the desired material properties; the evaporation behavior of the dopant at different crucible retention rates can be determined through the evaporation rate constant and the amount of dopant added can be controlled, thereby optimizing the production process of the single crystal silicon rod and further ensuring that the resistance of the head of the single crystal silicon rod finally obtained meets the design value requirements.

[0116] Specifically, a variety of analysis techniques can be used to monitor the change in the content of the dopant in the crucible. For example, spectral analysis technology can be used to perform spectral analysis on the gas above the crucible to determine the change in the intensity of the characteristic spectral lines of the dopant element, thereby indirectly inferring the evaporation amount of the dopant; or mass spectrometry technology can be used to directly measure the number of ions or molecules of the dopant evaporated into the gas phase, thereby calculating the evaporation amount of the dopant. The evaporation amount is measured at different time points, and as time goes by, the change data of the evaporation amount of the dopant over time is recorded, thereby calculating the evaporation rate.

[0117] In other optional schemes, the evaporation characteristic parameter includes an evaporation time constant, wherein the evaporation time constant is defined as C(t)=C0e -1 The acquisition unit includes: a first establishment module, for establishing a kinetic equation C(t)=C0e reflecting the relationship between the evaporation rate of the dopant and the content of the dopant in the crucible before the historical seeding step-kt , wherein C(t) is the content of the dopant in the crucible heated to time t before the historical seeding step, C0 is the content of the dopant in the crucible before heating, e is a natural constant, k is an evaporation rate constant of the dopant, and t is a time; a second acquisition module is used to obtain the remaining content of the dopant in the crucible corresponding to the crucible retention rate and the initial content of the dopant, and determine the evaporation rate constant corresponding to the crucible retention rate based on the remaining content, the initial content and the kinetic equation; a first determination module is used to determine, based on the evaporation rate constant, that the evaporation time constant corresponding to the crucible retention rate is the inverse of the evaporation rate constant, and obtain the evaporation characteristic parameter corresponding to the crucible retention rate.

[0118] Of course, in actual application, the evaporation characteristic parameters may include both the evaporation rate constant and the evaporation time constant.

[0119] In some embodiments, the first determination unit includes: a second determination module, which is used to determine the evaporation characteristic parameter corresponding to the target crucible retention rate as the target evaporation characteristic parameter according to multiple evaporation characteristic parameters; a third determination module, which is used to determine the side area volume ratio of the crucible according to the geometric parameters of the crucible; and a fourth determination module, which is used to determine the target evaporation coefficient as α=kRGS according to the target crucible retention rate, the target evaporation characteristic parameter, the side area volume ratio and the predetermined content ratio, wherein α is the target evaporation coefficient, k is the evaporation rate constant, R is the target crucible retention rate, G is the side area volume ratio, and S is the predetermined content ratio. In this embodiment, through the comprehensive consideration of multiple parameters such as the evaporation characteristic parameter, the crucible retention rate, the geometric parameters of the crucible and the predetermined content ratio, the evaporation coefficient of the dopant at the target crucible retention rate can be accurately determined, and the evaporation coefficient of the dopant under different crucible retention rates is quantified, which provides an accurate data basis for the subsequent determination of the compensation resistor based on the evaporation coefficient to achieve accurate compensation of the single crystal silicon rod head resistance.

[0120] Specifically, the process of determining the target evaporation characteristic parameter is to select the evaporation characteristic parameter corresponding to the same crucible retention rate as the target crucible retention rate from multiple evaporation characteristic parameters to obtain the target evaporation characteristic parameter. The target evaporation characteristic parameter is an evaporation rate constant.

[0121] In addition, when the evaporation characteristic parameters include the evaporation time constant, the target evaporation coefficient is determined as Here, τ is the evaporation time constant.

[0122] In actual application, the crucible is generally cylindrical, so the side area to volume ratio is Where r is the radius of the crucible and h is the height of the crucible.

[0123] According to some other embodiments of the present application, the second determination unit includes: a second establishment module, which is used to establish a relationship model between the evaporation coefficient and the compensation resistance at different crucible retention rates; a fifth determination module, which is used to determine the relationship model corresponding to the target crucible retention rate as the target relationship model based on multiple relationship models and the target crucible retention rate; an input module, which is used to input the target evaporation coefficient into the target relationship model to obtain the target compensation resistance. In this embodiment, based on the evaporation coefficient, a relationship between it and the compensation resistance of the head of the single crystal silicon rod is established, so as to achieve accurate compensation of the head resistance of the single crystal silicon rod, which greatly improves the accuracy and precision of the control of the head resistance of the single crystal silicon rod, and provides key technical support for the high-quality development of semiconductor silicon rod manufacturing. This control method can effectively reduce the problem of single crystal silicon rod head resistance deviation caused by the limitations of traditional methods, and further improve the consistency of the electrical performance of the single crystal silicon rod.

[0124] Specifically, one crucible retention rate corresponds to one relationship model, and a relationship model between the evaporation coefficient and the compensation resistance at different crucible retention rates can be established by means of data fitting or a neural network model.

[0125] In one embodiment, the second establishment module includes: an acquisition submodule for acquiring multiple different evaporation coefficients corresponding to the same crucible retention rate, and acquiring compensation resistors corresponding to multiple evaporation coefficients; a fitting submodule for performing nonlinear fitting on multiple evaporation coefficients and multiple compensation resistors to obtain a relationship model corresponding to the crucible retention rate. This solution uses a nonlinear fitting method to establish a relationship model between the evaporation coefficient and the compensation resistor at different crucible retention rates, which can achieve accurate prediction of the compensation resistor of the single crystal silicon rod head. According to the prediction result, the resistance compensation of the single crystal silicon rod head can be performed, which can further improve the production quality of the single crystal silicon rod head during the direct pulling process.

[0126] Specifically, the compensation resistance can be obtained by measuring the difference between the actual head resistance of the single crystal silicon rod obtained by the existing method (i.e., the method of adding a fixed amount of dopant to the silicon raw material) and the expected head resistance. The actual head resistance can be measured by using a high-precision resistance measurement technology such as a four-probe method to obtain accurate resistance value data. Different evaporation coefficients corresponding to the same crucible retention rate can be achieved by changing the geometry of the crucible, the initial silicon raw material content in the crucible, and the initial dopant content in the crucible.

[0127] In order to further solve the problem of large deviation between the actual value and the design value of the head resistance of the CZ-pulled single crystal silicon rod in the prior art, in the present application, the adding unit includes: a sixth determination module, which is used to determine the compensation amount of the dopant corresponding to the target compensation resistance according to the target compensation resistance; a seventh determination module, which is used to determine the initial addition amount of the dopant according to the target crumb retention rate and the expected resistance; and an eighth determination module, which is used to determine the target addition amount as the sum of the compensation amount and the initial addition amount. In this way, the calculation accuracy of the dopant addition amount is improved, and the effect of controlling the resistance deviation of the head of the single crystal silicon rod within a very small range is further achieved, thereby further improving the accuracy of the head resistivity of the CZ-pulled single crystal silicon rod, and further ensuring that the actual value of the head resistance of the CZ-pulled single crystal silicon rod is substantially equal to its design value.

[0128] Exemplarily, the adding unit includes: an adding module for adding a target amount of dopant to the crucible; and an adjusting module for adjusting the heating temperature of the crucible after the dopant is added according to the target crucible retention rate, so that the heating temperature is within a preset temperature range corresponding to the target crucible retention rate. In this embodiment, after adding the target amount of dopant to the crucible, the heating temperature of the crucible is adjusted to match the target crucible retention rate, ensuring that the silicon melt and dopant in the crucible are uniformly heated, thereby maintaining a stable thermal field distribution during the straight pulling process, and further ensuring the precise control of the resistance of the head of the single crystal silicon rod.

[0129] Optionally, when the dopant is an N-type dopant, the dopant includes at least one of the following: phosphorus, antimony, arsenic, bismuth; when the dopant is a P-type dopant, the dopant includes at least one of the following: boron, aluminum, gallium, indium, thallium. The above dopants are all volatile in a high temperature environment. The compensation measures based on their evaporation effect in this application can effectively avoid the resistivity deviation of the head of the single crystal silicon rod caused by the change of the crucible retention rate, thereby greatly improving the accuracy of the resistivity of the head of the single crystal silicon rod, ensuring that the electrical properties of the single crystal silicon rod meet the strict requirements of semiconductor manufacturing, and also providing a theoretical basis for further external field regulation of dopant segregation.

[0130] The control device for resistivity of a single crystal silicon rod includes a processor and a memory, wherein the acquisition unit, the first determination unit, the second determination unit, and the adding unit 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.

[0131] The processor includes a kernel, which retrieves the corresponding program unit from the memory. One or more kernels can be provided, and the problem of a large deviation between the actual value of the head resistance of the CZ single crystal silicon rod and the designed value in the prior art can be at least solved by adjusting the kernel parameters.

[0132] 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.

[0133] An embodiment of the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium includes a stored program, wherein when the program is run, a device where the computer-readable storage medium is located is controlled to execute a method for controlling the resistivity of a single crystal silicon rod.

[0134] An embodiment of the present invention provides a processor, which is used to run a program, wherein a method for controlling the resistivity of a single crystal silicon rod is executed when the program is run.

[0135] An embodiment of the present invention provides a device, the device including a processor, a memory, and a program stored in the memory and executable on the processor, and when the processor executes the program, at least the following steps are implemented:

[0136] Step S201, obtaining a plurality of evaporation characteristic parameters, the evaporation characteristic parameters being the evaporation characteristics of the dopant at different crucible retention rates before the historical seeding step, the crucible retention rate being the ratio of the amount of remaining material in the crucible to the initial amount of material in the crucible, the evaporation characteristic being a parameter characterizing the characteristics affected by the crucible retention rate during the evaporation process;

[0137] Step S202, determining the evaporation coefficient of the dopant before the current seeding step according to a plurality of evaporation characteristic parameters, a target crucible retention rate, geometric parameters of the crucible, and a predetermined content ratio, to obtain a target evaporation coefficient, wherein the target crucible retention rate is the crucible retention rate before the current seeding step, the predetermined content ratio is the ratio of the initial silicon raw material content in the crucible to the initial dopant content, and the evaporation coefficient represents the ease of evaporation of the dopant at the corresponding crucible retention rate;

[0138] Step S203, determining the compensation resistance of the head of the single crystal silicon rod according to the target evaporation coefficient to obtain the target compensation resistance, where the compensation resistance is the difference between the actual resistance of the head of the single crystal silicon rod and the expected resistance;

[0139] Step S204, determining a target addition amount of the dopant according to the target compensation resistance, and adding at least the target addition amount of the dopant into the crucible.

[0140] The devices in this article can be servers, PCs, PADs, mobile phones, etc.

[0141] The present application also provides a computer program product, including computer instructions, which, when executed by a processor, implement at least the following method steps:

[0142] Step S201, obtaining a plurality of evaporation characteristic parameters, the evaporation characteristic parameters being the evaporation characteristics of the dopant at different crucible retention rates before the historical seeding step, the crucible retention rate being the ratio of the amount of remaining material in the crucible to the initial amount of material in the crucible, the evaporation characteristic being a parameter characterizing the characteristics affected by the crucible retention rate during the evaporation process;

[0143] Step S202, determining the evaporation coefficient of the dopant before the current seeding step according to a plurality of evaporation characteristic parameters, a target crucible retention rate, geometric parameters of the crucible, and a predetermined content ratio, to obtain a target evaporation coefficient, wherein the target crucible retention rate is the crucible retention rate before the current seeding step, the predetermined content ratio is the ratio of the initial silicon raw material content in the crucible to the initial dopant content, and the evaporation coefficient represents the ease of evaporation of the dopant at the corresponding crucible retention rate;

[0144] Step S203, determining the compensation resistance of the head of the single crystal silicon rod according to the target evaporation coefficient to obtain the target compensation resistance, where the compensation resistance is the difference between the actual resistance of the head of the single crystal silicon rod and the expected resistance;

[0145] Step S204, determining a target addition amount of the dopant according to the target compensation resistance, and adding at least the target addition amount of the dopant into the crucible.

[0146] 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.

[0147] 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 in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0148] 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 1 A device that provides the functions specified in a block or multiple blocks.

[0149] 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 including 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.

[0150] 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 The steps for the functions specified in one or more boxes.

[0151] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0152] 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.

[0153] 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.

[0154] 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.

[0155] From the above description, it can be seen that the above embodiments of the present application achieve the following technical effects:

[0156] 1) The method of the present application first obtains the evaporation characteristic parameters of the dopant at multiple crucible retention rates before the historical seeding step; then determines the evaporation coefficient of the dopant before the current seeding step according to the multiple evaporation characteristic parameters, the crucible retention rate before the current seeding step, the geometric parameters of the crucible, and the content ratio of the silicon raw material initially loaded in the crucible to the dopant; then determines the compensation resistance of the head of the single crystal silicon rod according to the evaporation coefficient; finally, determines the addition amount of the dopant according to the compensation circuit, and adds the dopant to the crucible according to the addition amount, thereby compensating the resistance of the head of the single crystal silicon rod, so that the actual resistance after compensation meets the requirement of the expected resistance, fully considers the evaporation of the dopant at different crucible retention rates, can accurately compensate for the resistance change of the head of the single crystal silicon rod caused by the evaporation of the dopant, thereby controlling the resistance deviation of the head of the single crystal silicon rod within a very small range, and effectively solves the problem that the prior art does not fully consider the influence of factors such as the crucible retention rate on the evaporation of the dopant, resulting in a large deviation between the actual value of the head resistance of the CZ single crystal silicon rod and the design value.

[0157] 2) The device of the present application obtains the evaporation characteristic parameters of the dopant at multiple crucible retention rates before the historical seeding step through an acquisition unit; determines the evaporation coefficient of the dopant before the current seeding step through a first determination unit according to multiple evaporation characteristic parameters, the crucible retention rate before the current seeding step, the geometric parameters of the crucible, and the content ratio of the silicon raw material initially loaded in the crucible to the dopant; determines the compensation resistance of the head of the single crystal silicon rod according to the evaporation coefficient through a second determination unit; determines the addition amount of the dopant according to the compensation circuit through an adding unit, and adds the dopant to the crucible according to the addition amount, thereby compensating the resistance of the head of the single crystal silicon rod, so that the actual resistance after compensation meets the requirement of the expected resistance, fully considers the evaporation of the dopant at different crucible retention rates, can accurately compensate for the resistance change of the head of the single crystal silicon rod caused by the evaporation of the dopant, thereby controlling the resistance deviation of the head of the single crystal silicon rod within a very small range, and effectively solves the problem that the prior art does not fully consider the influence of factors such as the crucible retention rate on the evaporation of the dopant, resulting in a large deviation between the actual value of the head resistance of the CZ single crystal silicon rod and the design value.

[0158] 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 method for controlling the resistivity of a single crystal silicon rod, characterized in that: include: Acquire a plurality of evaporation characteristic parameters, wherein the evaporation characteristic parameters are evaporation characteristics of the dopant at different crucible retention rates before the historical seeding step, wherein the crucible retention rate is a ratio of the amount of remaining material in the crucible to the initial amount of material in the crucible, and the evaporation characteristic characterizes parameters of characteristics affected by the crucible retention rate during the evaporation process; Determine the evaporation coefficient of the dopant before the current seeding step according to the plurality of evaporation characteristic parameters, the target crucible retention rate, the geometric parameters of the crucible, and the predetermined content ratio to obtain a target evaporation coefficient, wherein the target crucible retention rate is the crucible retention rate before the current seeding step, the predetermined content ratio is the ratio of the initial silicon raw material content to the initial dopant content in the crucible, and the evaporation coefficient represents the ease of evaporation of the dopant at the corresponding crucible retention rate; According to the target evaporation coefficient, determining the compensation resistance of the head of the single crystal silicon rod to obtain the target compensation resistance, wherein the compensation resistance is the difference between the actual resistance of the head of the single crystal silicon rod and the expected resistance; A target addition amount of a dopant is determined according to the target compensation resistance, and at least the target addition amount of the dopant is added into the crucible.

2. The method according to claim 1, characterized in that Obtain multiple evaporation characteristic parameters, including: Establish a kinetic equation C(t)=C0e that reflects the relationship between the evaporation rate of the dopant and the content of the dopant in the crucible before the historical seeding step. -kt , wherein C(t) is the content of the dopant in the crucible heated to time t before the historical seeding step, C0 is the content of the dopant in the crucible before heating, e is a natural constant, k is the evaporation rate constant of the dopant, and t is the time; The remaining content of the dopant in the crucible corresponding to the crucible retention rate and the initial content of the dopant are obtained, and the evaporation rate constant corresponding to the crucible retention rate is determined according to the remaining content, the initial content and the kinetic equation to obtain the evaporation characteristic parameter corresponding to the crucible retention rate.

3. The method according to claim 2, characterized in that According to the plurality of evaporation characteristic parameters, the target crucible retention rate, the geometric parameters of the crucible and the predetermined content ratio, the evaporation coefficient of the dopant before the current seeding step is determined to obtain the target evaporation coefficient, including: According to the plurality of evaporation characteristic parameters, determining the evaporation characteristic parameter corresponding to the target crucible retention rate as the target evaporation characteristic parameter; Determining the lateral area to volume ratio of the crucible according to the geometric parameters of the crucible; According to the target crucible retention rate, the target evaporation characteristic parameter, the lateral area to volume ratio and the predetermined content ratio, the target evaporation coefficient is determined to be α=kRGS, wherein α is the target evaporation coefficient, k is the evaporation rate constant, R is the target crucible retention rate, G is the lateral area to volume ratio, and S is the predetermined content ratio.

4. The method according to claim 1, characterized in that According to the target evaporation coefficient, determining the compensation resistance of the head of the single crystal silicon rod to obtain the target compensation resistance includes: Establishing a relationship model between the evaporation coefficient and the compensation resistance at different crucible retention rates; According to the plurality of relationship models and the target crumb retention rate, determining the relationship model corresponding to the target crumb retention rate as a target relationship model; The target evaporation coefficient is input into the target relationship model to obtain the target compensation resistance.

5. The method according to claim 4, characterized in that The relationship model between the evaporation coefficient and the compensation resistance under different crucible retention rates includes: Obtaining a plurality of different evaporation coefficients corresponding to the same crucible retention rate, and obtaining the compensation resistors corresponding to the plurality of evaporation coefficients; Nonlinear fitting is performed on the plurality of evaporation coefficients and the plurality of compensation resistors to obtain the relationship model corresponding to the crucible retention rate.

6. The method according to claim 1, characterized in that Determining a target addition amount of a dopant according to the target compensation resistance includes: Determining, according to the target compensation resistance, a compensation amount of the dopant corresponding to the target compensation resistance; Determining the initial addition amount of the dopant according to the target crucible retention rate and the expected resistance; The target addition amount is determined as the sum of the compensation amount and the initial addition amount.

7. The method according to claim 1, characterized in that Adding at least the target amount of the dopant into the crucible comprises: adding the target amount of the dopant into the crucible; According to the target crucible retention rate, the heating temperature of the crucible after the dopant is added is adjusted so that the heating temperature is within a preset temperature range corresponding to the target crucible retention rate.

8. The method according to claim 1, characterized in that When the dopant is an N-type dopant, the dopant includes at least one of the following: phosphorus, antimony, arsenic, and bismuth; when the dopant is a P-type dopant, the dopant includes at least one of the following: boron, aluminum, gallium, indium, and thallium.

9. A device for controlling the resistivity of a single crystal silicon rod, characterized in that: include: an acquisition unit, for acquiring a plurality of evaporation characteristic parameters, wherein the evaporation characteristic parameters are evaporation characteristics of the dopant at different crucible retention rates before the historical seeding step, wherein the crucible retention rate is a ratio of the amount of remaining material in the crucible to the initial amount of material in the crucible, and the evaporation characteristic characterizes parameters of characteristics affected by the crucible retention rate during the evaporation process; A first determination unit is used to determine the evaporation coefficient of the dopant before the current seeding step according to a plurality of evaporation characteristic parameters, a target crucible retention rate, geometric parameters of the crucible, and a predetermined content ratio to obtain a target evaporation coefficient, wherein the target crucible retention rate is the crucible retention rate before the current seeding step, the predetermined content ratio is the ratio of the initial silicon raw material content to the initial dopant content in the crucible, and the evaporation coefficient represents the ease of evaporation of the dopant at the corresponding crucible retention rate; A second determination unit is used to determine the compensation resistance of the head of the single crystal silicon rod according to the target evaporation coefficient to obtain a target compensation resistance, wherein the compensation resistance is the difference between the actual resistance of the head of the single crystal silicon rod and the expected resistance; The adding unit is used to determine a target addition amount of a dopant according to the target compensation resistance, and to add at least the target addition amount of the dopant into the crucible.

10. An electronic device, characterized in that: include: One or more processors, a memory, and one or more programs, wherein 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 methods for executing any one of claims 1 to 8.

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