Method for producing nitrogen-doped single crystal silicon rods and nitrogen-doped single crystal silicon rods

Abstract

The embodiments of the present application disclose a method for producing a nitrogen-doped single crystal silicon rod and a nitrogen-doped single crystal silicon rod, the method including: cutting a reference nitrogen-doped single crystal silicon rod into sample silicon wafers, selecting a plurality of silicon wafers to be detected, and evaluating the distribution of defect areas of the plurality of silicon wafers to be detected; determining the distribution positions of each defect area in the reference nitrogen-doped single crystal silicon rod based on the distribution positions of each defect area in the plurality of silicon wafers to be detected; and during the production process of the current nitrogen-doped single crystal silicon rod, pulling up the reference nitrogen-doped single crystal silicon rod at the distribution positions of each defect area in the reference nitrogen-doped single crystal silicon rod at a target pulling speed corresponding to each set defect area to produce the current nitrogen-doped single crystal silicon rod.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority from Chinese Patent Application No. 202111165312.4, filed in China on September 30, 2021, the entire contents of which are incorporated herein by reference. Embodiments of the present application relate to the technical field of semiconductors, and in particular to a method for producing a nitrogen-doped single crystal silicon rod and a nitrogen-doped single crystal silicon rod. [Background technology]

[0002] Silicon wafers used as substrates for semiconductor integrated circuits are primarily produced by slicing single-crystal silicon rods extracted using the Czochralski method. The Czochralski method involves melting polysilicon raw material in a quartz crucible to obtain a silicon melt, immersing a seed crystal in the silicon melt, and continuously lifting and moving the seed crystal away from the surface of the silicon melt, allowing single-crystal silicon rods to grow at the phase interface during the process.

[0003] In the above-mentioned production process, it is highly advantageous to provide a silicon wafer having a denuded zone (DZ) extending from the front surface into the bulk and a region containing bulk microdefects (BMDs) adjacent to the DZ and extending further into the bulk. The "front surface" here refers to the surface of the silicon wafer where electronic components are to be formed. The DZ is important because, in order to form electronic components on the silicon wafer, the electronic component formation region must be free of crystalline defects, which would otherwise cause defects such as circuit breaks. Forming electronic components in the DZ avoids the effects of crystalline defects. The BMDs act as intrinsic getters (IGs) against metal impurities, keeping them away from the DZ and thereby preventing adverse effects such as increased leakage current and degradation of gate oxide film quality.

[0004] However, during the production process of silicon wafers having the above-mentioned BMD regions, it is highly advantageous to dope the silicon wafer with nitrogen. For example, doping the silicon wafer with nitrogen can promote the formation of nitrogen-based BMDs, allowing the BMDs to reach a certain density, which not only enables the BMDs to function effectively as metal gettering sources, but also has a beneficial effect on the BMD density distribution, such as making the BMD density distribution more uniform in the radial direction of the silicon wafer, or making the BMD density higher in the region near the DZ and gradually decreasing toward the bulk of the silicon wafer.

[0005] However, in the conventional growth process of nitrogen-doped single crystal silicon rods, in addition to doping the silicon melt with nitrogen, silicon wafers produced from the nitrogen-doped single crystal silicon rods also require a heat treatment process to generate BMDs within the silicon wafers, promoting the adsorption of impurities on the surface of the silicon wafers near the BMDs and further improving the surface cleanliness of the silicon wafers. Meanwhile, currently, when producing an entire doped single crystal silicon rod, the ratio of the pulling speed to the crystal temperature in the pulling axis direction (V / G) remains unchanged, resulting in the production of an entire doped single crystal silicon rod containing various grown-in defects. As a result, the content and density of BMDs throughout the entire doped single crystal silicon rod are non-uniform, and the proportion of silicon wafers with high surface cleanliness within the entire doped single crystal silicon rod is low, leading to waste of doped single crystal silicon rods. Summary of the Invention [Problem to be solved by the invention]

[0006] In view of this, the embodiment of the present application is as follows: vacancy The present invention provides a method for producing nitrogen-doped single crystal silicon rods that can produce nitrogen-doped single crystal silicon rods having only rich regions and that can produce a greater proportion of silicon wafers with high surface cleanliness, and also provides nitrogen-doped single crystal silicon rods. [Means for solving the problem]

[0007] The technical solution according to the embodiment of the present application is realized as follows.

[0008] In a first aspect, an embodiment of the present application provides a method for producing a nitrogen-doped single crystal silicon rod, comprising: After cutting into sample silicon wafers based on the reference nitrogen-doped single crystal silicon rod, selecting a plurality of silicon wafers to be detected, and evaluating the distribution of defect areas of the plurality of silicon wafers to be detected; Determining the location of the distribution of each defect area in the reference nitrogen-doped single crystal silicon rod based on the distribution of defect areas in the plurality of silicon wafers to be detected; During the process of producing the current nitrogen-doped single crystal silicon rod, the reference nitrogen-doped single crystal silicon rod is pulled at a target pulling speed corresponding to each of the set defect regions at the distribution position of each defect region in the reference nitrogen-doped single crystal silicon rod to produce the current nitrogen-doped single crystal silicon rod; Among them, the defect area includes: vacancy a rich region, an interstitial rich region, vacancy A method for fabricating nitrogen-doped single crystal silicon rods is provided, the rods including alternating nitrogen-rich and interstitial-rich regions.

[0009] In a second aspect, an embodiment of the present application provides a nitrogen-doped single crystal silicon rod produced by the production method described in the first aspect. [Effects of the Invention]

[0010] The embodiments of the present application provide a method for manufacturing a nitrogen-doped single crystal silicon rod and a nitrogen-doped single crystal silicon rod. This manufacturing method can determine the distribution position of each defect area in a reference nitrogen-doped single crystal silicon rod based on the distribution status of multiple silicon wafer defect areas to be detected. Therefore, during the manufacturing process of the current nitrogen-doped single crystal silicon rod, when the reference nitrogen-doped single crystal silicon rod is pulled up to the distribution position of each defect area, the current nitrogen-doped single crystal silicon rod is manufactured by being pulled up at the target pulling speed corresponding to each set defect area. According to this manufacturing method, the target pulling speed of the current single crystal silicon rod can be adjusted stepwise to vacancy It is possible to obtain nitrogen-doped single crystal silicon rods having only rich regions, and furthermore, it is possible to obtain a larger number of silicon wafers with high surface cleanliness. [Brief explanation of the drawings]

[0011] [Figure 1]1 is a schematic diagram showing the distribution of various defect regions present in a conventional nitrogen-undoped single crystal silicon rod according to an embodiment of the present application. [Figure 2] 1 shows one form of alternating distribution of vacancy-rich regions and interstitial-rich regions according to an embodiment of the present application. [Figure 3] 10 is another form of alternating distribution of vacancy-rich regions and interstitial-rich regions according to an embodiment of the present application. [Figure 4] 1 is a schematic flow diagram of a method for producing nitrogen-doped single crystal silicon rods according to an embodiment of the present application. [Figure 5] 1 is a schematic flow diagram of a process for preparing a silicon wafer to be detected using a reference nitrogen-doped single crystal silicon rod according to an embodiment of the present application. FIG. [Figure 6] 1 is a schematic diagram of the positions corresponding to different defect regions in a reference nitrogen-doped single crystal silicon rod according to an embodiment of the present application. FIG. [Figure 7] 1 is a schematic diagram illustrating the use of different target pulling rates at different positions in a current single crystal silicon rod according to an embodiment of the present application. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, the technical solutions in the embodiments of the present application will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present application.

[0013] Referring to Figure 1, a schematic diagram of the distribution of various defect regions present in a conventional nitrogen-undoped single crystal silicon rod S0 is shown, and in the examples of the present application, specifically, a radial cross section is used to show the distribution of various defect regions. As shown in Figure 1, vacancy Defective area (shown as the area shaded on the left in the figure), vacancy The figure includes rich regions (shown as filled diamond regions in the figure), interstitial rich regions (shown as filled diagonal lines in the figure), and interstitial defect regions (shown as filled blank regions in the figure). vacancyThe defect region includes large-sized defects such as lattice grown-in point defects (Crystal Originated Particles, COPs) in nitrogen-doped single crystal silicon rods and flow pattern defects (FPDs). vacancy The interstitial defect region includes large interstitial defects such as dislocations and slip lines, which are formed by the diffusion and aggregation of vacancy point defects during the cooling process. vacancy The rich region is an oxygen precipitation promotion region where oxygen precipitation occurs, and the interstitial rich region is vacancy an oxygen precipitation suppression region located between the rich region and the interstitial defect region, in which oxygen precipitation does not occur; vacancy Both the rich region and the interstitial rich region contain defects of very small dimensions, on the order of nanometer-scale defects, and therefore, both of these regions are considered to be defect-free regions with very few grown-in defects.

[0014] Most of the defect-free nitrogen-doped single crystal silicon rods currently on the market are mainly vacancy It is an alternating distribution of rich regions and interstitial rich regions. vacancy The alternating distribution of the rich regions and the interstitial rich regions can be divided into two main forms, as specifically shown in FIGS.

[0015] On the other hand, BMD is a type of vacancy In actual production, BMDs are formed by depositing on defects. vacancy Defective area and vacancy If the single crystal silicon rod is deposited in the rich region, vacancy If a defect region is included, it will affect the integrity of the gate oxide film of the silicon wafer produced from that single crystal silicon rod. In the interstitial rich region, impurity oxygen cannot be deposited, so BMD cannot be formed. vacancy Only nitrogen-doped single crystal silicon rods in the rich region can produce high density BMDs and produce silicon wafers with high surface cleanliness. However, defect-free nitrogen-doped single crystal silicon rods currently on the market have the following characteristics: vacancy a rich region, an interstitial rich region, vacancy The presence of defective regions in which rich regions and interstitial rich regions are alternately distributed simultaneously reduces the percentage of silicon wafers with high surface cleanliness that can be obtained from a single nitrogen-doped single crystal silicon rod.

[0016] Based on the above description, in order to achieve a uniform BMD content throughout a single nitrogen-doped single crystal silicon rod and increase the proportion of silicon wafers with high surface cleanliness, the embodiment of the present application controls and adjusts the parameter V / G: vacancy The aim is to produce nitrogen-doped single crystal silicon rods with only rich regions, and to obtain a greater proportion of silicon wafers with high surface cleanliness. However, in the case of a fixed hot zone structure, the G value is constant, so in the examples of this application, the growth rate is obtained by adjusting only the pulling speed V. vacancy The present invention aims to obtain a nitrogen-doped single crystal silicon rod having only a rich region. Therefore, referring to FIG. 4, an embodiment of the present invention provides a method for producing a nitrogen-doped single crystal silicon rod, and the method includes: After cutting into sample silicon wafers based on the reference nitrogen-doped single crystal silicon rod, a plurality of silicon wafers to be detected are selected, and the distribution of defect areas of the plurality of silicon wafers to be detected is evaluated, wherein the defect areas include: vacancy a rich region, an interstitial rich region, vacancy Step S401 includes a rich and interstitial rich alternating distribution region; The method includes step S402 of determining the distribution position of each defect region in the reference nitrogen-doped single crystal silicon rod based on the distribution of defect regions of the plurality of silicon wafers to be detected; and step S403 of, during the production process of the current nitrogen-doped single crystal silicon rod, pulling up the reference nitrogen-doped single crystal silicon rod at the distribution position of each defect region in the reference nitrogen-doped single crystal silicon rod at a target pulling speed corresponding to each set defect region, to produce the current nitrogen-doped single crystal silicon rod.

[0017] The technical solution shown in Figure 4 can determine the distribution position of each defect area in the reference nitrogen-doped single crystal silicon rod based on the distribution status of multiple silicon wafer defect areas to be detected, so that during the production process of the current nitrogen-doped single crystal silicon rod, when it is pulled up to the distribution position of each defect area in the reference nitrogen-doped single crystal silicon rod, it is pulled up at the target pulling speed corresponding to each set defect area, thereby producing the current nitrogen-doped single crystal silicon rod. According to this production method, the target pulling speed of the current single crystal silicon rod is gradually adjusted to vacancy It is possible to obtain nitrogen-doped single crystal silicon rods having only rich regions, and furthermore, it is possible to obtain a larger number of silicon wafers with high surface cleanliness.

[0018] For the technical solution shown in FIG. 4, in some examples, the method includes: cutting the above-mentioned reference nitrogen-doped single crystal silicon rod into sample silicon wafers; selecting a plurality of silicon wafers to be detected; and evaluating the distribution of defect areas of the plurality of silicon wafers to be detected; Pulling the reference nitrogen-doped single crystal silicon rod at a reference pulling speed to prepare the reference nitrogen-doped single crystal silicon rod, and cutting the reference nitrogen-doped single crystal silicon rod to obtain the sample silicon wafer; selecting a plurality of the sample silicon wafers located at different positions of the reference nitrogen-doped single crystal silicon rod as the silicon wafers to be detected, and evaluating the distribution of defect areas of the plurality of silicon wafers to be detected.

[0019] It can be understood that, as shown in FIG. 5, after a reference nitrogen-doped single crystal silicon rod S1 is prepared by pulling at a reference pulling speed V0, in order to determine the distribution of defect regions present in the reference nitrogen-doped single crystal silicon rod S1, in the embodiment of the present application, the reference nitrogen-doped single crystal silicon rod S1 is sliced ​​to obtain a plurality of sample silicon wafers W, and some of the sample silicon wafers W are selected as silicon wafers W to be detected for evaluating the distribution of defect regions.

[0020] It should be noted that the number of silicon wafers W to be detected is selected according to the specific actual situation.

[0021] On the other hand, in order to fully obtain the distribution of defect regions at each position in the reference nitrogen-doped single crystal silicon rod, in the embodiment of the present application, the silicon wafers W to be detected are selected from the sample silicon wafers W located at the head, middle, and tail of the reference nitrogen-doped single crystal silicon rod S1, as specifically shown in Figure 5. However, it should be noted that the selection method of the silicon wafers W to be detected in the embodiment of the present application is not limited to the selection method described above and shown in Figure 5, and can be specifically adjusted according to actual conditions.

[0022] Regarding the above example, in some specific implementations, the evaluating of the distribution of defect areas of the plurality of silicon wafers to be detected as described above includes: acquiring minority carrier lifetime data on the surfaces of the plurality of silicon wafers to be detected, and plotting a minority carrier lifetime map according to the minority carrier lifetime data on the surfaces of the plurality of silicon wafers to be detected; and evaluating a distribution of defect regions of the plurality of silicon wafers to be detected based on the minority carrier lifetime map.

[0023] Regarding the above example, in some specific embodiments, evaluating the distribution of defect regions of the plurality of silicon wafers to be detected based on the above-mentioned minority carrier lifetime map includes: When the minority carrier lifetime map is a circular map with a long lifetime, the silicon wafer to be detected corresponding to the circular map with a long lifetime is vacancy determining that the first silicon wafer to be detected contains only rich regions; When the minority carrier lifetime map is a map with a circular and low lifetime, a silicon wafer to be detected corresponding to the map with a circular and low lifetime is vacancy determining that the second silicon wafer to be detected includes an interstitial rich region surrounding the rich region; When the minority carrier lifetime map is a circular map with a high lifetime, the silicon wafer to be detected corresponding to the circular map with a high lifetime surrounds the interstitial rich region. vacancy determining that the third silicon wafer to be detected includes a rich region; and if the minority carrier lifetime map is a circular, low lifetime map, determining that the silicon wafer to be detected corresponding to the circular, low lifetime map is a fourth silicon wafer to be detected that includes only interstitial-rich regions.

[0024] It should be noted that the minority carrier lifetime data on the surface of the silicon wafer W to be detected can be obtained by a microwave photoconductivity decay method, but the specific method will not be described in detail in this application.

[0025] As can be understood, in the present embodiment, the minority carrier lifetime of the silicon wafer to be detected is the lifetime of the excited carriers when excited with energy (1.12 eV) greater than the forbidden band width of the semiconductor. vacancy -refers to the average time for minority carriers in an electron pair to recombine. vacancybecome majority carriers and electrons become minority carriers. vacancy The cause of the formation of rich defects is the promotion of oxygen precipitation during the crystal pulling process, which results in circular defects. vacancy Because a rich region has been created, the average time for minority carriers to recombine is long in this region. vacancy A minority carrier lifetime map including only rich regions is a circular map with a high lifetime. As a result, by scanning the minority carrier lifetime map of the entire surface of the silicon wafer to be detected, the silicon wafer to be detected corresponding to the circular map with a high lifetime is vacancy It can be determined that the silicon wafer to be first detected contains only rich regions.

[0026] Similarly, the formation of interstitial rich defects is caused by the suppression of oxygen precipitation during the crystal pulling process, resulting in the formation of circular interstitial rich regions, in which the average time for minority carriers to recombine is short. Therefore, a minority carrier lifetime map that includes only interstitial rich regions will be circular and have a short lifetime. As a result, by scanning the minority carrier lifetime map over the entire surface of the silicon wafer to be detected, it can be determined that the silicon wafer to be detected that corresponds to the circular and short lifetime map is the fourth silicon wafer to be detected that includes only interstitial rich regions. Therefore, by analyzing the minority carrier lifetime map, vacancy A distinction can be made between rich regions and interstitially rich regions.

[0027] at the same time, vacancy For a second silicon wafer to be detected that includes an interstitial rich region surrounding the rich region, vacancy Since the lifetime of minority carriers in the rich region is longer than that of minority carriers in the interstitial rich region, as shown in Figure 2 vacancyIn the case of a pattern including interstitial rich regions distributed so as to surround a rich region, a circular map with a short lifetime is obtained as the minority carrier lifetime map, whereas the map with interstitial rich regions surrounding the interstitial rich region is obtained as the minority carrier lifetime map. vacancy For the third silicon wafer to be detected including the rich region, vacancy Since the lifetime of minority carriers in the rich region is longer than that of minority carriers in the interstitial rich region, the minority carriers are distributed around the interstitial rich region as shown in Figure 3. vacancy In the case of a shape including a rich region, a circular map with a long lifetime is obtained as the minority carrier lifetime map.

[0028] For the technical solution shown in FIG. 4, in some examples, determining the distribution location of each defect area in the reference nitrogen-doped single crystal silicon rod based on the distribution of defect areas of the plurality of silicon wafers to be detected as described above may include: The aforementioned vacancy Based on the first silicon wafer to be detected, which contains only the rich region, vacancy Determining the location I of the distribution of rich regions; The aforementioned vacancy Based on a second silicon wafer to be detected, which includes an interstitial rich region surrounding a rich region, in the reference nitrogen-doped single crystal silicon rod vacancy determining a distribution location II of interstitial rich regions surrounding the interstitial rich regions; vacancy Based on the third silicon wafer to be detected, which contains a rich region, surrounding the interstitial rich region in the reference nitrogen-doped single crystal silicon rod. vacancy determining a position III of the distribution of the interstitial rich regions; and determining a position IV of the distribution of the interstitial rich regions in the reference nitrogen-doped single crystal silicon rod based on a fourth silicon wafer to be detected that includes only the interstitial rich regions.

[0029] It can be understood that, as shown in FIG. 6, once defect evaluation is performed on a plurality of silicon wafers W to be detected and the defect distribution conditions within each silicon wafer W to be detected are determined, it becomes possible to determine the types of defects contained at different positions in the reference nitrogen-doped single crystal silicon rod corresponding to each silicon wafer W to be detected and the locations of the defect areas.

[0030] Regarding the technical solution shown in FIG. 4, in some examples, during the preparation process of the above-mentioned current nitrogen-doped single crystal silicon rod, the reference nitrogen-doped single crystal silicon rod is pulled at the distribution position of each defect region in the reference nitrogen-doped single crystal silicon rod at the target pulling speed corresponding to each set defect region to prepare the current nitrogen-doped single crystal silicon rod; When the hot zone structure of the current nitrogen-doped single crystal silicon rod is consistent with the hot zone structure of the reference nitrogen-doped single crystal silicon rod, during the manufacturing process of the current nitrogen-doped single crystal silicon rod, In the reference nitrogen-doped single crystal silicon rod vacancy Pulling out using a reference crystal pull rate based on the location I of the distribution of the rich regions; In the reference nitrogen-doped single crystal silicon rod vacancy pulling out the crystal at a first target crystal pull rate V1 based on the location II of the distribution of interstitial rich regions surrounding the rich region; Surrounding the interstitial rich region in the reference nitrogen-doped single crystal silicon rod vacancy pulling the crystal at a second target crystal pull rate V2 based on the position III of the distribution of the rich region; and pulling the silicon rod using a third target crystal pull rate V3 based on the position IV of the distribution of interstitial rich regions in the reference nitrogen-doped single crystal silicon rod.

[0031] In the above example, in some specific embodiments, the first target crystal pull-up speed V1 is a reference crystal pull-up speed V0 ±0.001 mm / min to 0.002 mm / min; the second target crystal pulling speed V2 is the reference crystal pulling speed V0 ±0.002 mm / min to 0.003 mm / min; The third target crystal pull-up speed V3 is the reference crystal pull-up speed V0 ±0.003 mm / min to 0.006 mm / min.

[0032] Understandably, as shown in Figure 7, vacancy In order to obtain the current nitrogen-doped single crystal silicon rod S2 having only the rich region, different target pulling speeds are used for different defect regions, and by using such a method of setting the target pulling speed in stages, vacancy The present nitrogen-doped single crystal silicon rod S2 having only the rich region can be produced, and a larger proportion of silicon wafers with high surface cleanliness can be obtained.

[0033] It can be seen that, when comparing the current nitrogen-doped single crystal silicon rod with the reference nitrogen-doped single crystal, the two manufacturing processes have the same manufacturing process parameters except for the corresponding crystal pulling speed, specifically, the crucible rotation speed, nitrogen dopant doping method, hot zone structure, and protective atmosphere are all the same. Therefore, by studying the defect area of ​​the reference nitrogen-doped single crystal silicon rod, a method for improving the distribution of the defect area of ​​the current nitrogen-doped single crystal silicon rod can be obtained.

[0034] It should be noted that in the embodiments of the present application, the target pulling speed of the current nitrogen-doped single crystal silicon rod S2 can be controlled within the above range through the pulling speed adjustment method in the conventional technical solution.

[0035] Referring to FIG. 7, an embodiment of the present application further provides a nitrogen-doped single crystal silicon rod fabricated by the fabrication method described in the above technical solution.

[0036] It should be noted that the technical solutions described in the embodiments of this application can be arbitrarily combined unless they are contradictory.

[0037] The above is merely a specific embodiment of the present application, and the scope of protection of the present application is not limited thereto. Those skilled in the art can easily think of modifications and alternatives within the technical scope disclosed in the present application, and all such modifications and alternatives should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be in accordance with the scope of protection of the accompanying claims.

Claims

1. A method for producing a nitrogen-doped single crystal silicon rod, comprising: After cutting into sample silicon wafers based on the reference nitrogen-doped single crystal silicon rod, selecting a plurality of silicon wafers to be detected, and evaluating the distribution of defect areas of the plurality of silicon wafers to be detected; Determining the location of the distribution of each defect area in the reference nitrogen-doped single crystal silicon rod based on the distribution of defect areas in the plurality of silicon wafers to be detected; During the process of producing the current nitrogen-doped single crystal silicon rod, the reference nitrogen-doped single crystal silicon rod is pulled at a target pulling speed corresponding to each of the set defect regions at the distribution position of each defect region in the reference nitrogen-doped single crystal silicon rod to produce the current nitrogen-doped single crystal silicon rod; The defect region includes a vacancy-rich region, an interstitial-rich region, and an alternating vacancy-rich and interstitial-rich region; After cutting into sample silicon wafers based on the above-mentioned reference nitrogen-doped single crystal silicon rod, selecting a plurality of silicon wafers to be detected, and evaluating the distribution of defect areas of the plurality of silicon wafers to be detected, Pulling the reference nitrogen-doped single crystal silicon rod at a reference pulling speed to prepare the reference nitrogen-doped single crystal silicon rod, and cutting the reference nitrogen-doped single crystal silicon rod to obtain the sample silicon wafer; selecting a plurality of the sample silicon wafers located at different positions of the reference nitrogen-doped single crystal silicon rod as the silicon wafers to be detected, and evaluating the distribution of defect areas of the plurality of silicon wafers to be detected; The above-mentioned evaluating the distribution of defect areas of the plurality of silicon wafers to be detected includes: acquiring minority carrier lifetime data on the surfaces of the plurality of silicon wafers to be detected, and plotting a minority carrier lifetime map according to the minority carrier lifetime data on the surfaces of the plurality of silicon wafers to be detected; evaluating a distribution of defect regions of the plurality of silicon wafers to be detected based on the minority carrier lifetime map; Evaluating the distribution of defect regions of the plurality of silicon wafers to be detected based on the minority carrier lifetime map described above includes: If the minority carrier lifetime map is a map with a circular shape and a long lifetime, determining that the silicon wafer to be detected corresponding to the map with a circular shape and a long lifetime is a first silicon wafer to be detected that includes only vacancy-rich regions; If the minority carrier lifetime map is a circular map with a low lifetime, determining that the silicon wafer to be detected corresponding to the circular map with a low lifetime is a second silicon wafer to be detected that includes an interstitial-rich region surrounding a vacancy-rich region; If the minority carrier lifetime map is a map with an annular and high lifetime, determining that the silicon wafer to be detected corresponding to the map with an annular and high lifetime is a third silicon wafer to be detected including a vacancy-rich region surrounding an interstitial-rich region; If the minority carrier lifetime map is a circular map with a low lifetime, determining that the silicon wafer to be detected corresponding to the circular map with a low lifetime is a fourth silicon wafer to be detected that includes only interstitial rich regions.

2. Determining the location of the distribution of each defect area in the reference nitrogen-doped single crystal silicon rod based on the distribution of defect areas of the plurality of silicon wafers to be detected includes: Determining the distribution position I of the vacancy-rich region in the reference nitrogen-doped single crystal silicon rod based on the first silicon wafer to be detected that includes only the vacancy-rich region; Determining a distribution position II of the interstitial rich region surrounding the vacancy rich region in the reference nitrogen-doped single crystal silicon rod based on a second silicon wafer to be detected, which includes an interstitial rich region surrounding the vacancy rich region; Determining a distribution location III of the vacancy-rich region surrounding the interstitial-rich region in the reference nitrogen-doped single crystal silicon rod based on a third silicon wafer to be detected, which includes a vacancy-rich region surrounding the interstitial-rich region; and determining a position IV of the distribution of the interstitial rich region in the reference nitrogen-doped single crystal silicon rod based on a fourth silicon wafer to be detected that includes only the interstitial rich region.

3. During the process of producing the current nitrogen-doped single crystal silicon rod, the reference nitrogen-doped single crystal silicon rod is pulled at a target pulling speed corresponding to each set defect region at the distribution position of each defect region in the reference nitrogen-doped single crystal silicon rod to produce the current nitrogen-doped single crystal silicon rod; When the hot zone structure of the current nitrogen-doped single crystal silicon rod is consistent with the hot zone structure of the reference nitrogen-doped single crystal silicon rod, during the manufacturing process of the current nitrogen-doped single crystal silicon rod, Pulling out the reference nitrogen-doped single crystal silicon rod using a reference crystal pull rate based on the position I of the distribution of vacancy-rich regions in the reference nitrogen-doped single crystal silicon rod; Based on the position II of the distribution of the interstitial rich region surrounding the vacancy rich region in the reference nitrogen-doped single crystal silicon rod, a first target crystal pulling speed V １ and extracting the same using Based on the position III of the distribution of the vacancy-rich region surrounding the interstitial-rich region in the reference nitrogen-doped single crystal silicon rod, a second target crystal pulling speed V ２ and extracting the same using Based on the position IV of the distribution of the interstitial rich region in the reference nitrogen-doped single crystal silicon rod, a third target crystal pulling speed V ３ and drawing the film using a drawing tool.

4. The first target crystal pulling speed V １ is the reference crystal pulling speed V ０ ±0.001 to 0.002 mm / min, The second target crystal pulling speed V ２ is the reference crystal pulling speed V ０ ±0.002 mm / min to 0.003 mm / min, The third target crystal pulling speed V ３ is the reference crystal pulling speed V ０ The method according to claim 3, wherein the speed is ±0.003 mm / min to 0.006 mm / min.

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