Manufacturing system and method for silicon single crystals

Abstract

To provide a silicon single crystal manufacturing system and a manufacturing method capable of precisely finding a diameter of a silicon single crystal having crystal orientation of <111> at a crystal center shaft.SOLUTION: A system comprises a silicon single crystal pulling device 10 for pulling a silicon single crystal 3 having crystal shaft orientation of at least <111> by a Chokralsky method, and a diameter measuring device 30 for finding a target diameter from plural measured values, by measuring during pulling, a diameter of the silicon single crystal which is pulled while rotating. The diameter measuring device 30 finds the diameter by excluding measured value data having a difference equal to or over a predetermined threshold from plural measured value data, and using all or a part of the remaining measured value data. The pulling device 10 controls the diameter of the silicon single crystal on the basis of the diameter found by the diameter measuring device.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a silicon single crystal manufacturing system and a manufacturing method, and more particularly to a silicon single crystal manufacturing system and a manufacturing method in which the crystal orientation of the crystal central axis is <111>.

Background Art

[0002] In a method for manufacturing a silicon single crystal by the Czochralski method (CZ method), a method is known in which the diameter of the single crystal being pulled is detected, and the pulling speed and the heater supply power (heater temperature) are controlled based on the detected diameter, thereby controlling the diameter of the pulled silicon single crystal to be constant (see Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in a silicon single crystal in which the crystal orientation of the crystal central axis is <111>, a flat portion along the crystal central axis is formed on a part of the outer periphery of the straight body portion of the ingot being pulled, so the diameter of the straight body portion detected by the camera is different between the flat portion and the non-flat portion. If the pulling speed and the heater supply power (heater temperature) are controlled based on the diameter including the diameter of the flat portion, there is a problem that the target diameter cannot be maintained during pulling.

[0005] The problem to be solved by the present invention is to provide a silicon single crystal manufacturing system and a manufacturing method capable of accurately obtaining the diameter of a silicon single crystal in which the crystal orientation of the crystal central axis is <111>.

Means for Solving the Problems

[0006] The present invention relates to at least the crystal axis orientation <111> A silicon single crystal pulling apparatus for pulling a silicon single crystal using the Czochralski method, A silicon single crystal being pulled up while rotating , the above <111> Based on the crystal orientation, the region including a flat portion that appears on a part of the surface of the straight body portion of the silicon single crystal being pulled diameter 、 Measured during the lifting Then, multiple diameter measurements were obtained. , The aforementioned multiple diameter From the measured values Used in the aforementioned lifting device A diameter measuring device for determining the diameter, The diameter measuring device is, The aforementioned multiple diameter measurement value A difference of more than the predetermined threshold from the middle diameter measurement Value Exclude and the remaining diameter measurement value Using all or part of the above Used in lifting devices Find the diameter, The lifting device is determined by the diameter measuring device. , used in the aforementioned lifting device The above problem is solved by a silicon single crystal manufacturing system that controls the diameter of the silicon single crystal based on its diameter.

[0007] Furthermore, the present invention relates to a method for producing silicon single crystals by pulling silicon single crystals using the Czochralski method, A silicon single crystal being pulled up while rotating , the above <111> Based on the crystal orientation, the region including a flat portion that appears on a part of the surface of the straight body portion of the silicon single crystal being pulled diameter 、 Measured during the lifting Then, multiple diameter measurements were obtained. , The aforementioned multiple diameter measurement value A difference of more than the predetermined threshold from the middle diameter measurement Value Exclude and the remaining diameter measurement value Using all or part This is used when controlling the pulling of the silicon single crystal. Find the diameter, requested , used when controlling the pulling of the silicon single crystal The above problem is solved by a method for manufacturing silicon single crystals that controls the diameter of the silicon single crystal based on its diameter.

[0008] In the above invention, when excluding measurement value data having a difference of a predetermined threshold value or more from among the plurality of measured measurement value data, the plurality of measured measurement value data are arranged in ascending or descending order, when arranged in ascending order, a predetermined number of measurement value data are excluded from the minimum value side, when arranged in descending order, a predetermined number of measurement value data are excluded from the maximum value side, and then, the remaining measurement value data may be averaged to obtain the diameter.

[0009] In the above invention, the diameter measuring device includes a camera that photographs a predetermined portion of a silicon single crystal being lifted, the camera photographs the silicon single crystal being lifted while the silicon single crystal rotates once relative to the camera to obtain a plurality of photographed image data, and the plurality of measured measurement value data may be generated from the plurality of photographed image data.

[0010] In the above invention, it is more preferable that the predetermined number of measurement value data to be excluded is a number equal to or greater than the number of times the flat portion area appearing on the surface of the silicon single crystal being lifted is photographed by the camera.

[0011] In the above invention, the predetermined number may be set in advance in the diameter measuring device.

Advantages of the Invention

[0012] According to the present invention, measurement value data having a difference of a predetermined threshold value or more is excluded from among the plurality of measured measurement value data, and the diameter of the silicon single crystal is obtained using all or part of the remaining measurement value data, so that the diameter of a silicon single crystal whose crystal orientation of the crystal central axis is <111> can be accurately obtained.

Brief Description of the Drawings

[0013] [Figure 1] It is a longitudinal sectional view showing an embodiment of a silicon single crystal manufacturing system according to the present invention. [Figure 2]Figure 1 is a schematic perspective view showing an image of the boundary between a silicon single crystal and a silicon melt, captured by the camera shown. [Figure 3] The crystal orientation of the central axis of the crystal is <111> This is a perspective view showing an example of a silicon single crystal. [Figure 4] This is a cross-sectional view along the line IV-IV in Figure 3. [Figure 5] This figure shows an example of processing multiple measurement data measured by the diameter measuring device shown in Figure 1. [Figure 6] This figure shows another example of processing multiple measurement data measured by the diameter measuring device shown in Figure 1. [Figure 7] This figure shows yet another example of processing multiple measurement data measured by the diameter measuring device shown in Figure 1. [Modes for carrying out the invention]

[0014] Embodiments of the present invention will be described below with reference to the drawings. Figure 1 is a longitudinal cross-sectional view showing one embodiment of the silicon single crystal manufacturing system according to the present invention. As shown in Figure 1, the silicon single crystal manufacturing system 1 of this embodiment comprises a silicon single crystal pulling device 10 (hereinafter also simply referred to as the pulling device 10) and a diameter measuring device 30. The silicon single crystal pulling device 10 of this embodiment has at least the crystal axis orientation <111> Since it is sufficient to pull a silicon single crystal using the Czochralski method, the crystal orientation is <111> Other than, for example <100> It may also be used when pulling up silicon single crystals.

[0015] The silicon single crystal pulling apparatus 10 of this embodiment comprises a water-cooled chamber 11, a quartz crucible 12 for holding a silicon melt 2 inside the chamber 11, a graphite susceptor 13 for holding the quartz crucible 12, a rotating shaft 14 for supporting the graphite susceptor 13, a heater 15 arranged around the graphite susceptor 13, a heat shield 16 positioned above the quartz crucible 12, a pulling wire 17 which is a crystal pulling shaft positioned above the quartz crucible 12 and coaxial with the rotating shaft 14, a crystal pulling mechanism 18 positioned above the chamber 11, a drive mechanism 19 for rotating and raising / lowering the quartz crucible 12 via the rotating shaft 14 and the graphite susceptor 13, and a control unit 20 for controlling each part of the pulling apparatus 10.

[0016] Chamber 11 includes a main chamber 11a and an elongated cylindrical pull chamber 11b connected to the upper opening of the main chamber 11a. A quartz crucible 12, a graphite susceptor 13, a heater 15, and a heat shield 16 are provided in the main chamber 11a. The pull chamber 11b is provided with a gas inlet 11c for introducing an inert gas (purge gas) such as argon gas or a dopant gas into the chamber 11, and a gas outlet 11d for discharging the atmospheric gas from the chamber 11 is provided at the bottom of the main chamber 11a. In addition, a viewing window 11e is provided at the top of the main chamber 11a, allowing observation of the growth status of the silicon single crystal 3 through the viewing window 11e.

[0017] The quartz crucible 12 is a container having cylindrical side walls and a bottom. The graphite susceptor 13 holds the quartz crucible 12 in close contact with its outer surface, enclosing it, in order to maintain the shape of the quartz crucible 12 after it has softened due to heating. The quartz crucible 12 and the graphite susceptor 13 constitute a double-layered crucible that supports the silicon molten liquid 2 within the chamber 11.

[0018] The graphite susceptor 13 is fixed to the upper end of the rotating shaft 14, and the lower end of the rotating shaft 14 is connected to a drive mechanism 19 located outside the chamber 11, passing through the bottom of the chamber 11. The graphite susceptor 13, the rotating shaft 14, and the drive mechanism 19 constitute the rotation and lifting mechanisms of the quartz crucible 12. The rotation and lifting movements of the quartz crucible 12, driven by the drive mechanism 19, are controlled by the control unit 20.

[0019] The heater 15 is used to melt the silicon raw material packed in the quartz crucible 12 to produce a silicon melt 2, and to maintain the molten state of the silicon melt 2. The heater 15 is a carbon resistance heater and is positioned to surround the graphite susceptor 13 of the quartz crucible 12. Furthermore, an insulating material 11f is provided on the outside of the heater 15, surrounding it, thereby improving the heat retention of the chamber 11. The output of the heater 15 is controlled by the control unit 20.

[0020] The thermal shield 16 is provided to suppress temperature fluctuations in the silicon melt 2, provide an appropriate heat distribution near the crystal growth interface, and prevent heating of the silicon single crystal 3 by radiant heat from the heater 15 and the quartz crucible 12. The thermal shield 16 is a substantially cylindrical graphite member and is provided to cover the region above the silicon melt 2, excluding the pulling path of the silicon single crystal 3.

[0021] The diameter of the opening at the lower end of the heat shield 16 is larger than the diameter of the silicon single crystal 3, thereby ensuring a pulling path for the silicon single crystal 3. Furthermore, the outer diameter of the lower end of the heat shield 16 is smaller than the diameter of the quartz crucible 12, and the lower end of the heat shield 16 is located inside the quartz crucible 12. Therefore, even if the upper end of the side wall of the quartz crucible 12 is raised above the lower end of the heat shield 16, the heat shield 16 will not interfere with the quartz crucible 12.

[0022] As the silicon single crystal 3 grows, the amount of molten material in the quartz crucible 12 decreases. Therefore, the quartz crucible 12 is raised so that the gap between the molten material surface and the heat shield 16 remains constant. This gap control improves the stability of the crystal defect distribution, oxygen concentration distribution, resistivity distribution, etc., in the pulling axis direction of the silicon single crystal 3.

[0023] Above the quartz crucible 12, there is a pull wire 17, which is the pulling axis for the silicon single crystal 3, and a crystal pulling mechanism 18 that pulls up the silicon single crystal 3 by winding up the pull wire 17. The crystal pulling mechanism 18 has the function of rotating the silicon single crystal 3 together with the pull wire 17. The crystal pulling mechanism 18 is controlled by the control unit 20. The crystal pulling mechanism 18 is located above the pull chamber 11b, and the pull wire 17 hangs down from the crystal pulling mechanism 18 through the pull chamber 11b, with the tip of the pull wire 17 reaching the internal space of the main chamber 11a.

[0024] Figure 1 shows a silicon single crystal 3 in the process of growth suspended from a pulling wire 17. When pulling up the silicon single crystal 3, a seed crystal is attached to the tip of the pulling wire 17, and the silicon single crystal 3 is grown by gradually pulling up the pulling wire 17 while rotating the quartz crucible 12 and the seed crystal, starting from a state where the seed crystal is immersed in the silicon melt 2. The crystal pulling speed is controlled by the control unit 20.

[0025] The control unit 20 controls the crystal diameter during pulling in real time by controlling the crystal pulling speed and other parameters based on the crystal diameter data obtained from the diameter measuring device 30, which will be described later. Specifically, if the measured diameter is larger than the target diameter, the crystal pulling speed is increased, and if it is smaller than the target diameter, the crystal pulling speed is decreased. The control unit 20 also controls the amount of movement of the quartz crucible 12 (crucible raising speed) based on the crystal length data of the silicon single crystal 3 obtained from the sensor of the crystal pulling mechanism 18 and the crystal diameter data obtained from the image captured by the camera 31.

[0026] The diameter measuring device 30 consists of a camera 31 installed outside the chamber 11, a computer on which an image processing program for processing image data captured by the camera 31 is installed, and a memory for storing various types of data.

[0027] Camera 31 is, for example, a CCD camera, and it photographs the inside of the chamber 11 through a viewing window 11e formed in the chamber 11. The camera 31 is set at a predetermined angle with respect to the vertical direction, and the camera 31 has an optical axis inclined with respect to the pulling axis of the silicon single crystal 3. That is, the camera 31 photographs the opening of the heat shield 16, the liquid surface of the silicon molten liquid 2, and the single crystal from obliquely above. The installation position and installation angle of the camera 31 relative to the pulling device 10 are known.

[0028] Camera 31 is connected to a diameter measuring device that includes an image processing program, and diameter measuring device 30 is connected to the control unit 20. The image processing program included in diameter measuring device 30 calculates the crystal diameter near the solid-liquid interface from the contour pattern of the single crystal captured in the image taken by camera 31.

[0029] Next, the method for measuring the diameter of the silicon single crystal 3 using the diameter measuring device 30 will be described. In order to control the diameter of the silicon single crystal 3 during the pulling process, the boundary between the silicon single crystal 3 and the molten surface is photographed with a camera 31, and the diameter of the silicon single crystal 3 is determined from the center position of the fusion ring generated at the boundary and the distance between the two brightness peaks of the fusion ring. In addition, in order to control the liquid surface position of the silicon molten 2, the liquid surface position is determined from the center position of the fusion ring. The control unit 20 controls the pulling conditions such as the pulling speed of the pulling wire 17, the power of the heater 15, and the rotation speed of the quartz crucible 12 so that the diameter of the silicon single crystal 3 becomes the target diameter. The control unit 20 also controls the vertical position of the quartz crucible 12 so that the liquid surface position is at the desired position.

[0030] Figure 2 is a schematic perspective view showing an image of the boundary between the silicon single crystal 3 and the silicon melt 2, captured by the camera 31. As shown in Figure 2, the image processing program of the diameter measuring device 30 calculates the radius r and diameter R=2r of the fusion ring 4 from the coordinate position of the center C0 of the fusion ring 4 that occurs at the boundary between the silicon single crystal 3 and the silicon melt 2, and the coordinate position of an arbitrary point on the fusion ring 4. In other words, the image processing program calculates the diameter R of the silicon single crystal 3 at the solid-liquid interface. The position of the center C0 of the fusion ring 4 is the intersection point of the extension line 5 of the pulling axis of the silicon single crystal 3 and the melt surface.

[0031] Since camera 31 photographs the boundary between the silicon single crystal 3 and the molten surface from an oblique angle above, it cannot capture the fusion ring 4 as a perfect circle. However, since camera 31 is precisely installed in a predetermined position and at a predetermined angle in the lifting device 10, and these positions and angles are known, the approximately elliptical fusion ring 4 can be corrected to a perfect circle based on the viewing angle relative to the molten surface, and its diameter can be geometrically calculated from the corrected fusion ring 4.

[0032] Incidentally, the fusion ring 4 is a ring-shaped high-luminosity region formed by light reflected by the meniscus, and occurs around the entire circumference of the silicon single crystal 3, but it is not possible to see the fusion ring 4 on the back side of the silicon single crystal 3 from the viewing window 11e. Also, when viewing the fusion ring 4 through the gap between the lower opening 16a of the heat shield 16 and the silicon single crystal 3, if the diameter of the silicon single crystal 3 is large, a part of the fusion ring 4 located on the front side in the viewing direction (lower side in Figure 2) may be hidden behind the heat shield 16 and cannot be seen. In this case, the only visible parts of the fusion ring 4 are a part 4L on the front left side and a part 4R on the front right side when viewed from the viewing direction. Even when only a part of the fusion ring 4 can be observed in this way, it is possible to calculate its diameter from that part.

[0033] As described above, the silicon single crystal manufacturing system 1 of the present embodiment includes a diameter measuring device 30 including a camera 31 that photographs the inside of the chamber 11, estimates the diameter of the silicon single crystal 3 near the solid-liquid interface from the photographed image of the camera 31, and controls the crystal pulling conditions such as the crystal pulling speed so that this diameter becomes a desired diameter (for example, 305 to 320 mm for a 300 mm wafer).

[0034] By the way, when pulling up the silicon single crystal 3 with a crystal axis orientation of <111>, a flat portion 3b along the central axis is formed on a part of the outer periphery of the straight cylindrical portion 3a as shown in FIG. 3. FIG. 3 is a perspective view showing an example of a silicon single crystal ingot with a crystal orientation of <111> of the crystal central axis, and FIG. 4 is a cross-sectional view taken along line IV-IV of FIG. 3. As described above, the diameter measuring device 30 photographs the vicinity of the solid-liquid interface of the silicon single crystal 3 pulled up while rotating with the camera 31, extracts the coordinate position of an arbitrary point on the fusion ring 4 from this photographed image, and measures the diameter of the silicon single crystal 3. Therefore, as shown in FIG. 4, the diameter D1 obtained from the measured value when the coordinate position P1 of the flat portion 3b is extracted and the diameter D2 obtained from the measured value when the coordinate position P2 other than the flat portion 3b is extracted are such that D1 < D2 by the amount of the flat portion 3b, and if these diameters D1 and D2 are used as they are, an accurate diameter cannot be obtained.

[0035] Therefore, the diameter measuring device 30 of this embodiment determines the diameter D2 of the straight section 3a excluding the flat section 3b by performing the following processing. First, the camera 31 photographs multiple locations near the solid-liquid interface while the silicon single crystal 3 is being pulled up while rotating, thereby acquiring multiple image data. Although not particularly limited, the camera 31 photographs 30 to 50 locations near the solid-liquid interface while the silicon single crystal 3 is rotating, and the diameter measuring device 30 processes each of the obtained 30 to 50 image data to generate 30 to 50 measurement value data. Of these, it is preferable that the flat section 3b is photographed two or more times, and more preferably three or more times from the viewpoint of stable diameter control of the straight section. It is preferable that the timing of photography by the camera 31 be uniform with respect to the circumferential direction of the silicon single crystal, and it is preferable that the number of times the straight section 3a other than the flat section 3b is photographed is greater than the number of times the flat section 3b is photographed.

[0036] Once image data including the flat portion 3b is obtained, the diameter measuring device 30 excludes measurement data that differs by more than a predetermined threshold from among the multiple measurement data, and uses all or part of the remaining measurement data to determine the diameter of the silicon single crystal. Here, the method for excluding measurement data that differs by more than a predetermined threshold from among the multiple measurement data will be explained.

[0037] As shown in Figure 4, the difference between the diameter D1 obtained from the measurement when the coordinate position P1 of the flat portion 3b is extracted and the diameter D2 obtained from the measurement when the coordinate position P2 other than the flat portion 3b is extracted is approximately 10 mm for a 300 mm wafer, while it has been empirically observed that the variation in the diameter D2 obtained from the measurement when the coordinate position P2 other than the flat portion 3b is extracted is less than 1 mm. Therefore, when observing the distribution of the obtained multiple measurement data, it becomes as shown in Figure 5. Figure 5 is a diagram showing an example of processing of multiple measurement data measured by the diameter measuring device 30, where the vertical axis shows the measured diameter and the horizontal axis shows the parameter corresponding to the measurement location.

[0038] As described above, a flat section 3b appears. <111> In silicon single crystals with a specific crystal orientation, the difference between diameters D1 and D2, as shown in Figure 4, is large, while the variation in diameter D2 is significantly smaller in comparison. Therefore, as shown in Figure 5, a predetermined threshold can be set over a relatively wide range. That is, while the difference between diameters D1 and D2 is approximately 10 mm, the variation in diameter D2 is less than 1 mm, so the predetermined threshold can be set to any value between, for example, 3 and 8 mm.

[0039] Furthermore, the method for excluding measurement data with a difference exceeding a predetermined threshold from among multiple measured measurement data is not particularly limited, and various mathematical or statistical processing methods can be used. For example, from the multiple measurement data shown in Figure 5, one arbitrary measurement data is first extracted, and the difference between this arbitrary measurement data and all the remaining measurement data is calculated to classify the measurement data into those with small differences and those with large differences. If the one arbitrary measurement data extracted earlier is, for example, data measuring diameter D1, then there will be more measurement data with large differences than measurement data with small differences, so the measurement data with small differences from the extracted arbitrary measurement data are excluded. Conversely, if the one arbitrary measurement data extracted earlier is, for example, data measuring diameter D2, then there will be more measurement data with small differences than measurement data with large differences, so the measurement data with large differences are excluded.

[0040] The method for excluding measurement data with a difference exceeding a predetermined threshold from among multiple measured measurement data is not limited to this. Figure 6 shows another example of processing multiple measurement data measured by the diameter measuring device 30. In this example, first, all measured measurement data are sorted in ascending order, that is, from smallest to largest. The vertical axis in Figure 6 shows the measured diameter, and the horizontal axis shows the measurement data sorted in ascending order. The measurement values ​​increase from left to right in Figure 6. With the data sorted in this ascending order, a predetermined number of measurement data are excluded from the smallest value side. The predetermined number to be excluded here is specifically the two on the left side shown in Figure 6, but this predetermined number may be set in advance in the diameter measuring device 30. Since the number of times the flat portion 3b of the silicon single crystal is photographed by the camera 31 is known, and the number of measurement data obtained from this is also known, this number is set as the predetermined number in the diameter measuring device 30.

[0041] Alternatively, as shown in Figure 6, the difference between two adjacent measurement values ​​is calculated for the measurement data arranged in ascending order. If the difference exceeds a predetermined threshold, the smaller measurement value corresponds to diameter D1, and the larger measurement value corresponds to diameter D2. Therefore, measurement values ​​smaller than this boundary are excluded.

[0042] The method for excluding measurement data with a difference exceeding a predetermined threshold from among multiple measured measurement data is not limited to this. Figure 7 shows yet another example of processing multiple measurement data measured by the diameter measuring device 30. In this example, first, all measured measurement data are sorted in descending order, that is, from largest to smallest. The vertical axis in Figure 7 shows the measured diameter, and the horizontal axis shows the measurement data sorted in descending order. The measurement values ​​decrease from left to right in Figure 7. With the data sorted in descending order, a predetermined number of measurement data are excluded from the maximum value side. Specifically, the predetermined number to be excluded is the two on the right side shown in Figure 7, but this predetermined number may be set in advance in the diameter measuring device 30. Since the number of times the flat portion 3b of the silicon single crystal is photographed by the camera 31 is known, and the number of measurement data obtained from that is also known, this number is set as the predetermined number in the diameter measuring device 30.

[0043] Alternatively, as shown in Figure 7, the difference between two adjacent measurement values ​​is calculated for the measurement data arranged in descending order. If the difference exceeds a predetermined threshold, the smaller measurement value corresponds to diameter D1, and the larger measurement value corresponds to diameter D2. Therefore, measurement values ​​smaller than this boundary are excluded. [Explanation of symbols]

[0044] 1…Silicon single crystal manufacturing system 10…Silicon single crystal pulling device 11... Chamber 11a... Main Chamber 11b... Pull chamber 11c...Gas inlet 11d...Gas outlet 11e... Peephole 11f... Insulation material 12…Quartz crucible 13…Graphite susceptor 14…Rotation axis 15… Heater 16… Heat shield 17… Lifting wire 18…Crystal pulling mechanism 19…Drive mechanism 20... Control Unit 30…Diameter measuring device 31... Camera 2…Melting silicon 3…Silicon single crystal 3a…straight body part 3b...Flat area

Claims

1. A silicon single crystal pulling apparatus for pulling silicon single crystals with at least a crystal axis orientation of <111> using the Czochralski method, The device comprises a diameter measuring device that measures the diameter of a region including a flat portion that appears on a part of the surface of the straight body portion of a silicon single crystal being pulled up while rotating, based on the crystal orientation of the silicon single crystal being pulled up, and obtains multiple diameter measurements, and determines the diameter to be used in the pulling device from the multiple diameter measurements, The diameter measuring device excludes the diameter measurement values ​​that have a difference of more than a predetermined threshold from the plurality of diameter measurement values, and uses all or part of the remaining diameter measurement values ​​to determine the diameter to be used in the lifting device. The pulling device is a silicon single crystal manufacturing system that controls the diameter of the silicon single crystal based on the diameter used in the pulling device, which is determined by the diameter measuring device.

2. The diameter measuring device, in excluding diameter measurements that have a difference of more than a predetermined threshold from among the plurality of diameter measurements, The measured values ​​of the multiple diameters are arranged in ascending or descending order. When sorted in ascending order, a predetermined number of diameter measurements are excluded from the minimum value side. When sorted in descending order, a predetermined number of diameter measurements are excluded from the highest value side. Next, the silicon single crystal manufacturing system according to claim 1, wherein the diameter to be used in the pulling device is determined by averaging the measured values ​​of the remaining diameter.

3. The diameter measuring device includes a camera that photographs a predetermined location of the silicon single crystal while it is being pulled up. The camera captures multiple images of the silicon single crystal being pulled while it rotates once relative to the camera, and acquires multiple images of the silicon single crystal. A silicon single crystal manufacturing system according to claim 1 or 2, which generates the measured values ​​of the plurality of diameters from the plurality of captured image data.

4. The diameter measuring device, in excluding a diameter measurement value having a difference of more than a predetermined threshold from among the plurality of diameter measurement values, The measured values ​​of the multiple diameters are arranged in ascending or descending order. When sorted in ascending order, a predetermined number of diameter measurements are excluded from the minimum value side. When sorted in descending order, a predetermined number of diameter measurements are excluded from the highest value side. Next, the remaining diameter measurements are averaged to determine the diameter to be used in the lifting device. The diameter measuring device includes a camera that photographs a predetermined location of the silicon single crystal while it is being pulled up. The camera captures multiple images of the silicon single crystal being pulled while it rotates once relative to the camera, and acquires multiple images of the silicon single crystal. The multiple measured diameters are generated from the multiple captured image data, The silicon single crystal manufacturing system according to claim 1, wherein the predetermined number of diameter measurements to be excluded is greater than or equal to the number of times the camera photographs the flat region appearing on the surface of the silicon single crystal during pulling.

5. The silicon single crystal manufacturing system according to claim 4, wherein the predetermined number is set in advance in the diameter measuring device.

6. In a method for manufacturing silicon single crystals, in which a silicon single crystal having at least a crystal axis orientation of <111> is pulled by the Czochralski method, As the silicon single crystal is pulled up while rotating, the diameter of the region including a flat portion that appears on a part of the surface of the straight body of the silicon single crystal during the pulling process is measured during the pulling process based on the crystal orientation of <111>, and multiple diameter measurements are obtained. From the multiple measured diameters, the measured diameters that have a difference of more than a predetermined threshold are excluded, and the diameter used when controlling the pulling of the silicon single crystal is determined using all or part of the remaining measured diameters. A method for manufacturing a silicon single crystal, wherein the diameter of the silicon single crystal is controlled based on the diameter used when controlling the pulling of the silicon single crystal, which has been determined.

7. In excluding the measured diameter values ​​from the aforementioned plurality of measured diameter values ​​that have a difference of more than a predetermined threshold, The measured values ​​of the multiple diameters are arranged in ascending or descending order. When sorted in ascending order, a predetermined number of diameter measurements are excluded from the minimum value side. When sorted in descending order, a predetermined number of diameter measurements are excluded from the highest value side. Next, the method for manufacturing a silicon single crystal according to claim 6, wherein the diameter used when controlling the pulling of the silicon single crystal is determined by averaging the measured values ​​of the remaining diameter.

8. Using a camera, multiple image data are acquired by photographing a predetermined location of the silicon single crystal being pulled while the silicon single crystal rotates once relative to the camera. A method for manufacturing a silicon single crystal according to claim 6 or 7, which generates the measured values ​​of the plurality of diameters from the plurality of captured image data.

9. When excluding a diameter measurement value having a difference of more than a predetermined threshold from among the plurality of diameter measurement values, The measured values ​​of the multiple diameters are arranged in ascending or descending order. When sorted in ascending order, a predetermined number of diameter measurements are excluded from the minimum value side. When sorted in descending order, a predetermined number of diameter measurements are excluded from the highest value side. Next, the remaining diameter measurements are averaged to determine the diameter used when controlling the pulling of the silicon single crystal. Using a camera, multiple image data are acquired by photographing a predetermined location of the silicon single crystal being pulled while the silicon single crystal rotates once relative to the camera. The multiple measured diameters are generated from the multiple captured image data, The method for manufacturing a silicon single crystal according to claim 6, wherein the predetermined number of diameter measurements to be excluded is greater than or equal to the number of times the camera photographs the flat region appearing on the surface of the silicon single crystal during pulling.

10. A method for manufacturing a silicon single crystal according to claim 9, wherein the predetermined number is set in advance and the corresponding diameter measurement value is excluded.

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