Silicon single crystal manufacturing apparatus

Abstract

The present application provides a kind of silicon single crystal manufacturing device (1), with: chamber (50);Crucible (51), be arranged in chamber (50);Radiation thermometer (3), with the detection element (16) of detecting the radiation light from measurement object, the lens (15) of converging radiation light in detection element (16), viewfinder (17) for visual confirmation measurement object, and the mark (MK) of center with the optical axis (A) of lens (15) consistent;Photographic device (5), mark (MK) and measurement object are photographed via viewfinder (17);Display device (13), display the mark (MK) and measurement object photographed;Illumination device (63), measurement object is illuminated so as to be able to photograph;And adjusting device (4), in the state that measurement position can be adjusted by measurement with radiation thermometer (3), support radiation thermometer (3).

Description

TECHNICAL FIELD

[0001] The present application relates to a silicon single crystal manufacturing apparatus. BACKGROUND

[0002] The pulling of a silicon single crystal by the Czochralski method (CZ method) is performed by implanting a seed crystal into a silicon melt in a crucible and pulling the seed crystal upward with a pulling wire.

[0003] In the pulling of a silicon single crystal, the temperature of the surface of the silicon melt in the crucible is one of the important parameters, and by accurately measuring the temperature of the surface of the melt, the quality of the silicon single crystal can be precisely controlled.

[0004] In Document 1 (Japanese Patent Application Publication No. 2014-218402), a technique is disclosed in which a radiation thermometer and a two-dimensional thermometer are disposed in the upper portion of a pull chamber, and the temperature of the surface of the silicon melt is measured using these two thermometers.

[0005] Incidentally, in a radiation thermometer, the alignment of the measurement position is usually performed by visual adjustment using an attached finder, but the measurement distance from the finder of the radiation thermometer disposed in the upper portion of the pull chamber to the crucible is long, and in the visual adjustment by the measurer, there is a problem in that the measurement position varies and is unstable depending on the observer's feeling and the angle of observation.

[0006] In addition, when the chamber is dark because there is no silicon melt in the chamber, visual adjustment has been conventionally performed in the state in which there is a silicon melt (a luminescent object). However, in this case, there is a problem in that although the marking can be seen by visual observation, the target position cannot be accurately known. SUMMARY

[0007] The present application aims to provide a silicon single crystal manufacturing apparatus in which the measurement position measured by a radiation thermometer can be accurately aligned with respect to the target position in a silicon single crystal manufacturing apparatus in which the temperature of the surface of a silicon melt is measured by a radiation thermometer.

[0008] The silicon single crystal manufacturing apparatus of the present application is characterized by comprising: a chamber; a crucible disposed in the chamber; a radiation thermometer having a detection element that detects radiation light from a measurement object, a lens that condenses the radiation light on the detection element, a finder that visually confirms the measurement object, and a marking whose center coincides with the optical axis of the lens; a photographing device that photographs the marking and the measurement object via the finder; a display device that displays the photographed marking and measurement object; an illumination device that illuminates the measurement object so as to be photographable; and an adjustment device that supports the radiation thermometer in a state in which the measurement position measured by the radiation thermometer can be adjusted.

[0009] In the silicon single crystal manufacturing apparatus described above, the aforementioned photographing device can be a camera capable of photographing an image.

[0010] In the silicon single crystal manufacturing apparatus described above, the aforementioned camera can have a high-depth lens capable of photographing both the aforementioned mark and the aforementioned measurement position at the same time.

[0011] In the silicon single crystal manufacturing apparatus described above, the aforementioned high-depth lens can be a liquid lens.

[0012] In the silicon single crystal manufacturing apparatus described above, the aforementioned photographing device can have a camera fixing jig for fixing the aforementioned camera to the aforementioned viewfinder; the aforementioned camera fixing jig can have a connection shaft formed in a cylindrical shape and connected to the aforementioned viewfinder; a camera holding portion having an insertion portion into which the aforementioned connection shaft can be inserted and holding the aforementioned camera; and a fixing member fixing the aforementioned camera holding portion to the aforementioned connection shaft in a state in which the aforementioned connection shaft is inserted into the aforementioned insertion portion.

[0013] In the silicon single crystal manufacturing apparatus described above, the aforementioned connection shaft can have a connection portion connected to the aforementioned viewfinder; and a cylindrical portion integrated with the aforementioned connection portion, in a cylindrical shape, having a male thread groove formed on an outer circumferential surface on a side opposite to the aforementioned connection portion, and capable of passing through the inside to confirm the aforementioned viewfinder; and the aforementioned insertion portion can be a U-shaped groove having an open lower portion and a terminal end portion formed in a circular arc having an inner diameter of the same size as an outer diameter of the aforementioned cylindrical portion; and the aforementioned fixing member can be screwed into the male thread groove of the aforementioned connection shaft, and fix the aforementioned camera holding portion in a state in which the aforementioned cylindrical portion is inserted into the aforementioned insertion portion.

[0014] In the silicon single crystal manufacturing apparatus described above, the aforementioned adjustment device can be a two-axis goniometer stand supporting the aforementioned radiation thermometer.

[0015] In the silicon single crystal manufacturing apparatus described above, there can be a base plate supporting the aforementioned two-axis goniometer stand; a mounting plate disposed between the aforementioned radiation thermometer and the aforementioned two-axis goniometer stand; a plurality of stop bolts having a shaft portion screwed into a female thread hole formed in the aforementioned base plate and a head portion in contact with a lower surface of the aforementioned mounting plate; and a nut fixing a height of the aforementioned stop bolts.

[0016] In the silicon single crystal manufacturing apparatus described above, there can be a reflection portion reflecting an optical path of radiation light measured by the aforementioned radiation thermometer in a direction orthogonal to an incident direction.

[0017] In the silicon single crystal manufacturing apparatus described above, the aforementioned reflection portion can have a mirror main body formed of an aluminum evaporation mirror.

[0018] In the silicon single crystal manufacturing apparatus described above, a crucible shaft that rotatably and vertically movably supports the crucible and a coordinate plate that is detachably attached to the crucible shaft and is photographed by the photographing device can be provided.

[0019] According to the present application, in a silicon single crystal manufacturing apparatus that measures the temperature of the surface of a silicon melt with a radiation thermometer, the measurement position measured by the radiation thermometer can be accurately aligned with respect to the target position. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 is a longitudinal sectional view showing the schematic structure of an embodiment of the silicon single crystal manufacturing apparatus according to the present application.

[0021] Figure 2 is a perspective view showing an embodiment of the radiation thermometer unit fixed to the pull chamber cover according to the present application.

[0022] Figure 3 is a perspective view showing a part of an embodiment of the adjustment device according to the present application.

[0023] Figure 4 is a partially cutaway side view showing the configuration of an embodiment of the radiation thermometer and the reflecting portion according to the present application.

[0024] Figure 5 is an exploded perspective view of an embodiment of the photographing device according to the present application.

[0025] Figure 6 is a perspective view of an embodiment of the camera holding portion according to the present application.

[0026] Figure 7A are a plan view and a side view of an embodiment of the coordinate plate according to the present application.

[0027] Figure 7B are a plan view and a side view of an embodiment of the coordinate plate according to the present application.

[0028] Figure 8 is a schematic view showing the state of fixation of the coordinate plate in the round plate fixation process.

[0029] Figure 9 is a view showing an example of a photographed image displayed on the display device. DETAILED DESCRIPTION

[0030] Hereinafter, an embodiment for carrying out the present application will be described with reference to the drawings.

[0031] Figure 1is a longitudinal sectional view showing a schematic configuration of an embodiment of a silicon single crystal manufacturing apparatus relating to the present application. The silicon single crystal manufacturing apparatus 1 manufactures a silicon single crystal SM using the CZ method.

[0032] As shown in Figure 1 , the silicon single crystal manufacturing apparatus 1 is provided with a chamber 50, a crucible 51, a heater 52, a pulling section 53, a heat shield 54, a heat insulating member 55, a crucible shaft 56, and a radiation thermometer unit 2.

[0033] The chamber 50 is provided with a main chamber 57 in which pulling of a crystal is performed, and a pulling chamber 58 which is connected to an upper portion of the main chamber 57 and in which a pulled crystal is accommodated. In the pulling chamber 58, a gas introduction port 59 which introduces a non-active gas such as argon (Ar) gas into the main chamber 57 is provided. In a lower portion of the main chamber 57, a gas exhaust port (not shown) which exhausts gas in the main chamber 57 by driving of a vacuum pump is provided.

[0034] The pulling chamber 58 has a cylindrical pulling chamber main body 58A, and a pulling chamber cover 58B which seals an upper end of the pulling chamber main body 58A. In the pulling chamber cover 58B, a measurement window 58C is provided. The measurement window 58C can be formed of a material which transmits radiation light and visible light from the silicon melt M, such as quartz.

[0035] In the main chamber 57, an observation window 57A for observing the inside of the main chamber 57 is provided. In the vicinity of the observation window 57A and outside of the main chamber 57, an illumination device 63 which illuminates a measurement object so as to enable photographing is provided. The illumination device 63 is disposed so as to irradiate the crucible 51 and a coordinate plate 35 (refer to Figure 8 ) which will be described later. As the illumination device 63, an LED lamp is preferable. According to experiments by the inventors, the light amount of the LED lamp is sufficient by being set to 70 lumens (lumen) or more and 200 lumens or less, and by being set to such a light amount, it is possible to reduce the cost as compared to an illumination device which is made to be 1000 lumens, for example.

[0036] The radiation thermometer unit 2 is fixed to the pulling chamber cover 58B, and measures the temperature of a measurement position of the silicon melt surface via the measurement window 58C. In addition, the distance from the radiation thermometer unit 2 to the silicon melt surface is about 6 m.

[0037] In an upper portion of the pulling chamber 58, a maintenance deck 60 is provided. An operator can perform work (adjustment, measurement, etc.) on the radiation thermometer unit 2 on the maintenance deck 60.

[0038] The crucible 51 is disposed in the main chamber 57, and stores the silicon melt M.

[0039] The heater 52 is arranged at a prescribed interval outside the crucible 51 to heat the silicon melt M inside the crucible 51. The pulling section 53 has a cable 61 having a seed crystal SC attached to one end, and a pulling drive section 62 that raises and rotates the cable 61.

[0040] The heat shield 54 is arranged so as to surround the silicon single crystal SM being pulled, and interrupts the radiant heat from the heater 52 toward the silicon single crystal SM. The crucible shaft 56 is a support shaft that supports the crucible 51 from below, and is connected to a drive device (not shown) that rotates and raises the crucible 51 at a prescribed speed. In addition, the crucible 51 is detachably attached to the crucible shaft 56, and the coordinate plate 35 described later is detachably attached to the crucible shaft 56 in place of the crucible 51.

[0041] Next, the radiant thermometer unit 2 will be described.

[0042] The radiant thermometer unit 2 is a unit that has the radiant thermometer 3 that measures the temperature of the surface of the silicon melt inside the crucible 51 at the time of manufacturing the silicon single crystal SM.

[0043] Figure 2 is a perspective view of the radiant thermometer unit 2 fixed to the pulling chamber cover 58B.

[0044] As shown in Figure 2 , the radiant thermometer unit 2 has the radiant thermometer 3 that non-contact measures the temperature of the surface of the silicon melt, the adjustment device 4 that adjusts the measurement position at which measurement is performed by the radiant thermometer 3, the photographing device 5 that photographs the measurement position at which measurement is performed by the radiant thermometer 3, the display device 13 (refer to Figure 1 ), and the reflection section 6.

[0045] The reflection section 6 reflects the optical path P of the radiant light (infrared rays) measured by the radiant thermometer 3 in the orthogonal direction with respect to the incident direction. The optical path P of the radiant light from the silicon melt M is reflected in the orthogonal direction by the reflection section 6 and is incident to the lens 15, and is measured by the radiant thermometer 3.

[0046] The viewfinder 17 of the radiant thermometer 3 is normally used at the time of temperature measurement by visual observation, but in the radiant thermometer unit 2 of the present application, the photographing device 5 is attached to the viewfinder 17. By this, the photographing device 5 can photograph the measurement position via the radiant thermometer 3 and the reflection section 6.

[0047] The radiant thermometer 3 is fixed to the pulling chamber cover 58B via the adjustment device 4. In the radiant thermometer unit 2 of the present embodiment, the radiant thermometer 3 is arranged so that the optical axis A of the lens 15 becomes substantially horizontal.

[0048] Figure 3is an exploded perspective view of a portion of the adjustment device 4. The adjustment device 4 is fixed to the pull chamber cover 58B, and is a device that supports the radiation thermometer 3 and adjusts a measurement position at which measurement is performed by the radiation thermometer 3.

[0049] The adjustment device 4 has a base plate 7 fixed to the pull chamber cover 58B, a two-axis goniometer stage 8 fixed to the base plate 7, and a mount plate 9 fixed to the two-axis goniometer stage 8 and supporting the radiation thermometer 3.

[0050] The base plate 7 is a plate-shaped member fixed to the pull chamber cover 58B with fastening members such as bolts B1 (refer to Figure 2 ) and the like. The base plate 7 can be formed of a plate having sufficient strength to support the radiation thermometer 3 and the two-axis goniometer stage 8. The base plate 7 is fixed to the pull chamber cover 58B with its upper surface horizontal. The two-axis goniometer stage 8 is fixed to the upper surface of the base plate 7 with, for example, bolts (not shown).

[0051] A plurality of stop bolts 10 can be installed in the base plate 7. The stop bolt 10 is a bolt having a shaft portion 10A that is screwed into a female threaded hole of the base plate 7 and a head portion 10B provided with a pad of resin. The stop bolt 10 is adjusted so that the pad of the head portion 10B is in contact with the lower surface of the mount plate 9.

[0052] The two-axis goniometer stage 8 is a device used in adjustment of the posture of the radiation thermometer 3 supported by the adjustment device 4. By adjusting the posture of the radiation thermometer 3 with the two-axis goniometer stage 8, the angle of the optical axis A of the lens 15 of the radiation thermometer 3 is adjusted, and the measurement position at which measurement is performed by the radiation thermometer 3 is adjusted.

[0053] The two-axis goniometer stage 8 is a structure in which two single-axis goniometer stages (tilt stages) are combined with their respective centers of rotation orthogonal to each other, and has a first goniometer stage 11 disposed on the base plate 7 and a second goniometer stage 12 connected to the upper side of the first goniometer stage 11.

[0054] The first goniometer stage 11 has a first fixed stage 11A, a first movable stage 11B connected to the upper side of the first fixed stage 11A, and a first handle 11C. The upper surface of the first fixed stage 11A is a cylindrical curved surface centered on an axis parallel to the Y axis (refer to Figure 3 ), and the lower surface of the first movable stage 11B is along the curved surface of the upper surface of the first fixed stage 11A. By turning the first handle 11C, the first movable stage 11B is turned about the axis parallel to the Y axis.

[0055] The second angle measuring stage 12 has a second fixed stage 12A, a second movable stage 12B connected above the second fixed stage 12A, and a second handle 12C. The upper surface of the second fixed stage 12A is oriented perpendicular to the X-axis (see reference). Figure 3 The second movable stage 12B is a cylindrical curved surface centered on a parallel axis, and the lower surface of the second movable stage 12B is a curved surface along the upper surface of the second fixed stage 12A. By rotating the second handle 12C, the second movable stage 12B rotates about an axis parallel to the X-axis.

[0056] Here, the X-axis is an axis that passes through the center of chamber 50 and extends horizontally, and the Y-axis is an axis that is orthogonal to the X-axis and extends horizontally.

[0057] Mounting plate 9 is fixed to the upper surface of the second goniometer stage 12 by fastening components such as bolts B2, and is a plate-shaped component disposed between the radiation thermometer 3 and the biaxial goniometer stage 8. Mounting plate 9 can be formed of a plate with sufficient strength to support the radiation thermometer 3. Multiple radiation thermometer mounting holes 9A are formed on mounting plate 9 for use when fixing the radiation thermometer 3 to mounting plate 9.

[0058] Next, the structure of the radiation thermometer 3 will be explained. Figure 4 This is a side view showing a partial cross-section of the structure of the radiation thermometer 3 and the reflector 6.

[0059] like Figure 4 As shown, the radiation thermometer 3 has a generally cylindrical housing 14, a lens 15 disposed within the housing 14, a detection element 16 disposed within the housing 14, and a viewfinder 17.

[0060] The lens 15 is configured such that its optical axis A is aligned with the central axis of the housing 14. That is, by setting the radiation thermometer 3 so that the central axis of the housing 14 is horizontal, the optical axis A of the lens 15 can be made horizontal.

[0061] The radiation thermometer 3 is a type of radiation thermometer that focuses the radiation light from the object being measured, which is taken in through the opening 14A formed in the housing 14, onto the sensing element 16 via the lens 15 and the beam splitter 18. The beam splitter 18 is a component used to separate the radiation light from the visible light; for example, a half mirror can be used.

[0062] The detection element 16 is a component that senses radiation light and generates an electrical signal corresponding to the energy of the radiation light.

[0063] The radiation thermometer 3 has a mark (e.g., a black circle) whose center aligns with the optical axis A of the lens 15. The mark is recorded with its center as the measurement center. This mark can typically be formed directly on the lens 15, but it can also be formed outside the lens 15. Furthermore, the distance coefficient of the radiation thermometer 3 is selected based on the measurement distance (e.g., 6000 mm in this embodiment) and the size of the object being measured.

[0064] Next, the reflector 6 will be described. The reflector 6 is a mechanism used to bend the light path P of the radiated light at a right angle.

[0065] like Figure 4 As shown, the reflector 6 includes a reflector housing 30 fixed to the housing 14 of the radiation thermometer 3, a reflector body 31 fixed inside the reflector housing 30, and a shielding tube 32 connected to the lower part of the reflector housing 30 and shielding the reflector housing 30 from the measuring window 58C. Furthermore, a slight gap is provided between the shielding tube 32 and the measuring window 58C so that the shielding tube 32 will not collide with the measuring window 58C when the radiation thermometer 3 is tilted using the biaxial goniometer stage 8.

[0066] The reflector housing 30 is a housing that houses the reflector body 31 so that the reflector body 31 is at an appropriate angle relative to the optical axis A of the lens 15. The reflector housing 30 has the function of blocking external light.

[0067] The reflector body 31 is formed of a material capable of reflecting both infrared and visible light. The reflector body 31 can be formed, for example, from an aluminum vapor-deposited reflector. However, the reflector body 31 is not limited to aluminum vapor-deposited reflectors; for example, a gold vapor-deposited reflector can also be used. While gold vapor-deposited reflectors have high reflectivity under optimal conditions in the infrared and near-infrared wavelengths, silicon is known to have a wavelength of approximately 0.6 μm (600 nm) at around 600°C, and thus becomes a short wavelength at high temperatures. In this region, there is no significant difference in reflectivity between aluminum vapor-deposited and gold vapor-deposited reflectors. Therefore, an aluminum vapor-deposited reflector, which is less expensive than a gold vapor-deposited reflector, can be used.

[0068] The shielding tube 32 is a cylindrical component connected to the lower part of the reflector housing 30. The shielding tube 32 has the function of blocking external light between the reflector housing 30 and the measuring window 58C.

[0069] Next, the photographic device 5 will be explained. Figure 5 This is an exploded perspective view of the photographic device 5. Furthermore, in the following description, the lens 15 of the radiation thermometer 3 (see reference...) will be used... Figure 4 The direction of the optical axis A is called the axial direction DA. Furthermore, the directions used in the description of the various components of the photographic apparatus 5, such as the vertical direction DV and the axial direction DA, correspond to...Figure 5 .

[0070] As shown in FIG. 1, a photographing apparatus 5 has a camera 19 and a camera fixing jig 20 for fixing the camera 19 to a viewfinder 17. Figure 5

[0071] The camera 19 is a device capable of photographing an image, and has a high depth lens 19A and a cable 19B for power supply. The main body of the camera 19 is in a cuboid shape, and a female screw hole 19C used in fixing the camera 19 is formed in the lower surface thereof. For the camera 19, power supply can be performed by, for example, a portable battery of a charging type.

[0072] Further, the camera 19 is provided with the high depth lens 19A capable of photographing from a close distance (for example, 100 mm) to a long distance (for example, 6000 mm) at the same time. The high depth lens 19A can employ, for example, a mechanism using a liquid lens. The liquid lens is a lens capable of changing a focal distance by electrically controlling the curvature of the interface between two kinds of liquids of the same density. The liquid lens uses two kinds of liquids of the same density, for example, oil as an insulator and water as a conductor, and changes the curvature of the interface between the two kinds of liquids by changing the voltage, to change the focal distance of the lens.

[0073] Further, the camera 19 has a data transceiving function by wireless communication (for example, wireless LAN). An operator can confirm the image photographed by the camera 19 via the display device 13 (refer to FIG. 2). Figure 1

[0074] The display device 13 can be a device capable of wireless communication with the camera 19, for example, a terminal such as a tablet, and can be configured to be capable of various setting operations of the camera 19 such as focusing and exposure by installing control software of the camera 19.

[0075] The structure of the camera 19 is not limited to the above-described structure, and the display device 13 can be integrated with the camera 19 to be configured to have no wireless communication function. In the present embodiment, a vision sensor In-Sight 2000 series manufactured by Cognex Corporation is employed as the camera 19, but any device having the same function can be employed, and is not limited thereto.

[0076] The camera fixing jig 20 has a connection shaft 21 fixed to the viewfinder 17, a camera holding portion 22 holding the camera 19 and fixed to the connection shaft 21, and a fixing member 23 as a nut for fixing the camera holding portion 22 to the connection shaft 21.

[0077] ​​The connecting shaft 21 has a connecting portion 24 that connects to the viewfinder 17, and a cylindrical portion 25 integral with the connecting portion 24. The connecting shaft 21 functions as a component for fixing the camera retaining portion 22 to the base of the viewfinder 17.

[0078] The connecting part 24 is a nut-shaped portion that engages with a male threaded groove formed on the outer peripheral surface of the viewfinder 17 of the radiation thermometer 3. The outer peripheral surface of the connecting part 24 is knurled. By knurling the outer peripheral surface of the connecting part 24 to provide a non-slip function, it is easier to install the connecting shaft 21 onto the viewfinder 17.

[0079] The cylindrical portion 25 is a cylindrical part that is coaxial with the connecting portion 24. The inner diameter of the cylindrical portion 25 is such that the size of the viewfinder 17 can be determined by passing through the interior of the cylindrical portion 25. On the outer peripheral surface of the cylindrical portion 25, opposite to the connecting portion 24, a male threaded groove 25A is formed that engages with the fixing member 23.

[0080] The outer diameter of the connecting portion 24 is larger than that of the cylindrical portion 25, and the connecting portion 24 has a contact surface 24A that contacts the base portion 40 (described later) when assembled into the photographic device 5. In this embodiment, the connecting portion 24 is cylindrical in shape when viewed from the axial direction, but it is not limited to this and may also be polygonal.

[0081] The camera holding part 22 has a bracket part 27 fixed to the connecting shaft 21, and a camera support part 28 integral with the bracket part 27 and supporting the camera 19.

[0082] like Figure 5 and Figure 6 As shown, the bracket portion 27 is a part that is U-shaped when viewed from above, having a base portion 40 fixed to the connecting shaft 21 and a pair of arm portions 41 protruding from both ends of the base portion 40 in a direction away from the connecting shaft 21.

[0083] The base portion 40 is a rectangular plate-shaped component. The base portion 40 is fixed to the connecting shaft 21 by being clamped by the connecting portion 24 and the fixing component 23 of the connecting shaft 21.

[0084] The base portion 40 has a U-shaped insertion portion 42 that is open at the bottom and into which the cylindrical portion 25 of the connecting shaft 21 is inserted. The insertion portion 42 consists of an arc portion 42A with a semi-circular shape at its upper end and a pair of straight portions 42B that connect the two ends of the arc portion 42A to the lower long side 40A of the base portion 40 and are parallel to each other. In other words, the insertion portion 42 is a cut formed from the lower long side 40A toward the upper long side 40B, and the end of the cut is made into an arc.

[0085] The inner diameter of the circular arc portion 42A is the same size as the outer diameter of the cylindrical portion 25 of the connecting shaft 21, and the pair of straight portions 42B are spaced apart from each other by a size slightly larger than the diameter of the cylindrical portion 25 of the connecting shaft 21.

[0086] In addition, the insertion portion 42 into which the connecting shaft 21 is inserted does not necessarily have to be U-shaped, but can be a simple circular hole. If the insertion portion 42 is U-shaped, the connecting shaft 21 can be inserted from below and attached to the base portion 40, so that attachment is facilitated.

[0087] The arm portion 41 is rectangular plate-shaped, and is connected to both ends of the base portion 40 with the main surfaces of the arm portion 41 parallel to each other.

[0088] The camera support portion 28 is rectangular plate-shaped, and is a portion that supports the lower surface of the camera 19 from below.

[0089] In the camera support portion 28, a circular hole 28A that corresponds to a female threaded hole 19C formed in the lower surface of the camera 19 is formed.

[0090] Next, the method of attaching the camera 19 using the camera fixing jig 20 will be described.

[0091] First, the connecting shaft 21 is fixed to the viewfinder 17. Further, the camera 19 is fixed to the camera holding portion 22 using the bolt B3. Next, the camera holding portion 22 is fixed to the connecting shaft 21 using the fixing member 23 in a state in which the circular arc portion 42A of the insertion portion 42 is in contact with the cylindrical portion 25 of the connecting shaft 21.

[0092] By attaching the camera 19 to the viewfinder 17 using the camera fixing jig 20, the camera 19 can photograph the mark and the measurement object of the radiation thermometer 3 via the viewfinder 17, and the optical axis of the high-depth lens 19A of the camera 19 and the optical axis A of the lens 15 of the radiation thermometer 3 are substantially aligned, so that the mark is displayed at the substantially center of the photographed image.

[0093] By attaching the camera 19 to the viewfinder 17, the high-depth lens 19A of the camera 19 faces the viewfinder 17 via the inside of the cylindrical portion 25, and the mark and the measurement object of the radiation thermometer 3 are imaged.

[0094] Next, the coordinate plate 35 used when adjusting the measurement position of the measurement using the radiation thermometer 3 using the adjustment device 4 will be described. The coordinate plate 35 is a circular plate that is fixed to the upper end of the crucible shaft 56 after the crucible 51 is removed, and functions as an imaginary liquid surface that simulates the surface of the silicon melt when adjusting the measurement position of the measurement using the radiation thermometer 3.

[0095] Figure 7A and Figure 7Bis a plan view and a side view of the coordinate plate 35. As shown in Figure 7A and Figure 7B The coordinate plate 35 is a member in the shape of a circular plate. The coordinate plate 35 is fixed to the upper end of the crucible shaft 56 with its main face horizontal.

[0096] Preferably, the coordinate plate 35 is formed of a material, such as a resin such as polytetrafluoroethylene, which is not problematic even if it comes into contact with the crucible shaft 56.

[0097] The coordinate plate 35 is formed with a pattern that functions as a coordinate when recording a target position on one face by groove processing. As the pattern, either a lattice-shaped pattern Figure 7A or a pattern composed of a plurality of circles in the shape of concentric circles and a plurality of lines extending in a radial fashion from the center Figure 7B may be used. Further, each of these patterns can be formed on the front face and the back face of the coordinate plate 35, respectively.

[0098] Next, a method of adjusting the temperature measurement position using the silicon single crystal manufacturing apparatus 1 described above will be described.

[0099] The method of manufacturing a silicon single crystal has a target position decision process, a coordinate plate fixing process, a photographing process, and an adjustment process.

[0100] The target position decision process is a process of deciding a target position in the surface of the silicon melt at which effective crystal quality control by temperature measurement is possible.

[0101] In the target position decision process, for example, the temperature distribution of the surface of the silicon melt measured by the two-dimensional thermometer is measured. Next, based on the measured temperature distribution, a region of constant low temperature at which the temperature is lower than at other regions is determined. Next, a target position is set inside this region of constant low temperature. At this time, the target position T can also be recorded on the coordinate plate 35 (refer to Figure 9 ).

[0102] In the coordinate plate fixing process, as shown in Figure 8 , the coordinate plate 35 is attached to the upper end of the crucible shaft 56 in a state in which the crucible 51 has been removed. Next, the coordinate plate 35 is moved so that the upper face of the coordinate plate 35 becomes the same height as the surface of the silicon melt by moving the crucible shaft 56 up and down.

[0103] In the photographing process, after the illuminance is ensured to the extent that the coordinate plate 35 can be photographed using the lighting device 63, photographing of the marks of the radiation thermometer 3 and the coordinate plate 35 as the measurement object is performed by the photographing device 5 via the viewfinder 17. Figure 9 is an example of a photographed image. As shown in Figure 9As shown, the display device 13 displays a photographic image of the mark MK of the radiation thermometer 3 and the coordinate plate 35 (target position T) at the same time. Such a photographic image is obtained by adjusting the depth of focus in advance by the high depth lens.

[0104] In the adjustment process, the adjustment device 4 is operated so that the target position T coincides with the center of the mark MK in the photographic image. The operator can operate the adjustment device 4 while confirming the photographic image displayed on the display device 13.

[0105] Specifically, first, the head of the set bolt 10 initially in contact with the lower surface of the mounting plate 9 is lowered by screwing the set bolt 10 into the base plate 7, and is separated from the lower surface of the mounting plate 9 by about 5 to 10 mm in advance. Next, the radiation thermometer 3 is rotated with the axis along the Y axis as the center by rotating the first handle 11C of the two-axis goniometer stand 8, and is rotated with the axis along the X axis as the center by rotating the second handle 12C. By using the two-axis goniometer stand 8, the measurement position is moved by about 10.5 mm (tan 0.1° x 6000 mm) by imparting a tilt of 0.1°, for example, from the measurement position of 6 m. Thus, the measurement position of the radiation thermometer 3 can be adjusted accurately.

[0106] After the adjustment to the target position is completed, the head of the set bolt 10 is raised by loosening the screwing of the set bolt 10 from the base plate 7, and after it is brought into contact with the lower surface of the mounting plate 9, the height of the set bolt 10 is fixed by screwing the two hexagonal nuts 10C disposed between the set bolt 10 and the base plate 7 toward the base plate 7 side.

[0107] Next, the coordinate plate 35 is detached from the crucible shaft 56, and the crucible 51 is installed. Further, the camera fixing jig 20 is detached from the viewfinder 17.

[0108] According to the above-described embodiment, by observing the photographic image photographed by the photographic device 5 while adjusting the measurement position for measurement by the radiation thermometer 3, the measurement position for measurement by the radiation thermometer 3 can be accurately aligned to the target position compared to the adjustment performed while visually observing the viewfinder 17. That is, in the visual adjustment performed while visually observing the viewfinder 17, the measurement position varies depending on the feeling and the angle of observation of the operator, and is unstable, but in the adjustment performed while observing the photographic image, the mark MK is displayed by overlapping with the coordinate plate 35, and thus the difference due to the operator can be eliminated. Thus, the temperature measurement of the silicon melt surface can be performed while pulling the silicon single crystal at the desired position.

[0109] Further, by displaying the photographic image on the display device 13 disposed away from the camera 19, the operator can confirm the photographic image in a free posture.

[0110] Further, by making the structure that the camera holding portion 22 is installed in the viewfinder 17 by installing the connecting shaft 21, fitting the insertion portion 42 of the base portion 40 in the connecting shaft 21, and fastening with the fixing member 23, the camera holding portion 22 can be easily attached and detached with respect to the connecting shaft 21.

[0111] Further, by making the structure that the positioning of the camera 19 is performed by making the circular arc portion 42A of the insertion portion 42 contact the cylindrical portion 25 of the connecting shaft 21, the reproducibility of the positioning of the camera 19 can be improved, and the installation error of each worker can be eliminated.

[0112] Further, since the camera 19 has a focus mechanism that can adjust the focus distance, the image photographing with the focus at both the mark MK and the coordinate plate 35 can be performed, and the display device 13 can be displayed.

[0113] Further, since the adjustment of the adjustment device 4 can be performed while confirming the displayed photographing image of the coordinate plate 35 or the like with the display device 13, the work by one worker can be performed.

[0114] Further, by using the two-axis goniometer stage 8 as the adjustment device 4, the fine adjustment of the measurement position at which the radiation thermometer 3 performs the measurement can be performed. Further, since the measurement position of the radiation thermometer 3 is changed only by the angle adjustment by the two-axis goniometer stage 8, the tightening of the bolt of the fixing installation plate 9 or the like is not required after the adjustment, and the variation of the measurement position does not occur.

[0115] Further, after the adjustment of the two-axis goniometer stage 8, by fixing the stop bolt 10 in the state that the head portion of the stop bolt 10 contacts the lower surface of the installation plate 9, the variation of the temperature measurement position due to the variation with time or the mechanical micro-vibration generated from the silicon single crystal manufacturing device 1, or the like of the two-axis goniometer stage 8 can be suppressed.

[0116] Further, since it is recommended that the setting on the horizontal plane is performed with respect to the goniometer stage, by making the structure that the light path P of the radiation light is reflected in the orthogonal direction with the reflection portion 6, the adjustment work using the two-axis goniometer stage 8 can be performed. Further, by the combination of the reflection portion 6 and the two-axis goniometer stage 8, the work on the maintenance table 60 can be performed, and the adjustment work can be made easy.

[0117] Further, by using the aluminum evaporation mirror as the reflection mirror of the reflection portion 6, compared with the gold evaporation glass reflection mirror, the reflection mirror whose color condition is suitable for the camera visual confirmation can be made.

[0118] Further, by using the camera that can be supplied with the power with the chargeable portable battery as the camera 19, the portability of the camera 19 is improved, and the work at a high place can be made easy.

[0119] Further, in the adjustment process, by using the coordinate plate 35 which functions as an imaginary liquid surface which simulates the surface of the silicon melt, the grasping of the set target position becomes easy, and the adjustment using the photographic image can be made easy.

[0120] [Modified example]

[0121] The present application is not limited to the structures described in the above embodiments, and modified examples within the range capable of achieving the object of the present application are included in the present application.

[0122] In the above embodiment, the camera holding portion 22 is made into a structure in which the cradle portion 27 and the camera support portion 28 are integrated, but is not limited thereto. For example, the cradle portion 27 and the camera support portion 28 can be made into a separate structure, and the camera support portion 28 can be slidably mounted in the axis direction DA on the cradle portion 27. By making such a structure, the position of the axis direction DA of the camera 19 can be adjusted.

[0123] Further, in the above embodiment, a structure in which the camera holding portion 22 is mounted via the connecting shaft 21 after the connecting shaft 21 is fixed to the viewfinder 17 is made, but is not limited thereto. For example, the viewfinder 17 can be made longer in the axis direction DA, and the viewfinder 17 and the camera holding portion 22 can be directly fixed.

[0124] Further, a biaxial goniometer stage is employed as the adjustment device 4, but as long as a device capable of adjusting the measurement position at which the radiation thermometer 3 performs measurement can be employed, other structures can be employed. For example, as the adjustment device 4, a stage device in which an X axis, a Y axis, and a θ axis are independent of each other can be employed.

[0125] Further, in the above embodiment, a structure in which the reflection portion 6 is provided to reflect the radiation light is made, but is not limited thereto, and a structure in which the radiation thermometer 3 directly takes in the radiation light can be made. For example, by mounting an L-shaped cradle on the biaxial goniometer stage, and mounting the radiation thermometer 3 on the L-shaped cradle such that the optical axis is in the vertical direction, the reflection portion 6 can be omitted.

[0126] Further, the coordinate plate 35 does not need to be made into a circular plate, and can be polygonal. The mark provided to the radiation thermometer 3 is not limited to a black circle, and the shape and color thereof can be appropriately set.

Claims

1. A silicon single crystal production apparatus characterized by comprising: a chamber; a crucible disposed in the chamber; a radiation thermometer having a detection element that detects radiation light from a measurement object, a lens that condenses the radiation light on the detection element, a viewfinder that visually confirms the measurement object, and a mark whose center coincides with an optical axis of the lens; a photographing device that photographs the mark and the measurement object via the viewfinder; a display device that displays the photographed mark and measurement object; an illuminating device that illuminates the measurement object so as to be photographable; a crucible shaft that detachably mounts the crucible and drives the crucible to rotate and to be raised and lowered; a coordinate plate that is detachably mounted to the crucible shaft and is photographed by the photographing device; and an adjustment device that supports the radiation thermometer in a state where a measurement position at which measurement is performed by the radiation thermometer is adjustable and is operated so that a target position on the coordinate plate and the center of the mark coincide.

2. The silicon single crystal production apparatus according to claim 1, characterized in that the photographing device is a camera that can photograph an image.

3. The silicon single crystal production apparatus according to claim 2, characterized in that the camera has a high-depth lens that can photograph both the mark and the measurement position at the same time.

4. The silicon single crystal production apparatus according to claim 3, characterized in that the high-depth lens is a liquid lens.

5. The silicon single crystal production apparatus according to claim 2, characterized in that the photographing device has a camera fixing jig that fixes the camera to the viewfinder; the camera fixing jig has: a connection shaft that is formed in a cylindrical shape and is connected to the viewfinder; a camera holding portion that has an insertion portion into which the connection shaft is inserted and holds the camera; and a fixing member that fixes the camera holding portion to the connection shaft in a state where the connection shaft is inserted into the insertion portion.

6. The silicon single crystal production apparatus according to claim 5, characterized in that the connection shaft has: a connection portion that is connected to the viewfinder; and a cylindrical portion that is integrated with the connection portion and is in a cylindrical shape, has a male thread groove formed on an outer circumferential surface on a side opposite to the connection portion, and can pass through the inside to confirm the viewfinder; the insertion portion is a U-shaped groove that is open at a lower portion thereof and has a terminal end that is formed in a circular arc having an inner diameter that is the same size as an outer diameter of the cylindrical portion; and the fixing member is screwed into the male thread groove of the connection shaft and fixes the camera holding portion in a state where the cylindrical portion is inserted into the insertion portion.

7. The silicon single crystal production apparatus according to claim 1, characterized in that the adjustment device is a two-axis goniometer stand that supports the radiation thermometer.

8. The silicon single crystal production apparatus according to claim 7, characterized by comprising: a base plate that supports the two-axis goniometer stand; a mounting plate that is disposed between the radiation thermometer and the two-axis goniometer stand; a plurality of set screws that have a shaft portion that is screwed into a female thread hole formed in the base plate and a head portion that contacts a lower surface of the mounting plate; and ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ A nut fixes the height of the aforementioned stop bolt.

9. The silicon single crystal production apparatus according to Claim 1, wherein The aforementioned reflecting section has a reflecting mirror main body formed of an aluminum evaporation reflecting mirror.

10. The silicon single crystal production apparatus according to Claim 9, wherein The aforementioned reflecting section has a reflecting mirror main body formed of an aluminum evaporation reflecting mirror.

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