Single crystal silicon manufacturing apparatus

Abstract

The present application provides a single crystal silicon manufacturing device (1), the single crystal silicon manufacturing device (1) has cavity (50), crucible (51), radiation thermometer (3), light source (5), adjusting device (4), the crucible (51) is arranged in cavity (50), the radiation thermometer (3) has the detecting element (16) of detecting the radiation light from the measured object, the lens (15) of converging radiation light to detecting element (16) and the viewfinder (17) for visually confirming measured object, the light source (5) supplies light to measured object along the axis line coinciding with the optical axis (A) of lens (15) via viewfinder (17) and lens (15), and the adjusting device (4) supports radiation thermometer (3) in the state that the measured position of radiation thermometer (3) can be adjusted.

Description

TECHNICAL FIELD

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

[0002] The pulling of single crystal silicon based on the Czochralski method (CZ method) is performed by pulling a seed crystal upward by a pulling wire while the seed crystal is embedded in a silicon melt in a crucible.

[0003] In the pulling of single crystal silicon, 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 silicon melt, the quality of the single crystal silicon 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 pulling chamber, and the temperature of the surface of the silicon melt is measured using these two thermometers.

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

[0006] Further, when there is no silicon melt in the chamber, the chamber is dark, and so far, visual adjustment has been usually performed in a state in which there is a silicon melt (a luminescent object). However, in this case, there is a problem in that the mark can be visually observed but the target position cannot be accurately known. SUMMARY

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

[0008] The single crystal silicon manufacturing apparatus of the present application includes a chamber, a crucible, a radiation thermometer, a light source, and an adjustment device, the crucible is disposed in the chamber, the radiation thermometer has a detection element that detects radiation light from a measurement object, a lens that condenses the radiation light onto the detection element, and a viewfinder that visually confirms the measurement object, the light source supplies light to the measurement object along an axis that coincides with the optical axis of the lens via the viewfinder and the lens, and the adjustment device supports the radiation thermometer in a state in which the measurement position of the radiation thermometer can be adjusted.

[0009] In the above single crystal silicon manufacturing apparatus, the light source can be a laser device that emits laser light.

[0010] In the single crystal silicon manufacturing apparatus, the aforementioned radiation thermometer can have a mark at the center of the optical axis of the aforementioned lens, and the aforementioned laser device can have a focal point variable mechanism.

[0011] In the single crystal silicon manufacturing apparatus, the aforementioned adjustment device can be a two-axis goniometer that supports the aforementioned radiation thermometer.

[0012] In the single crystal silicon manufacturing apparatus, the aforementioned adjustment device can be a two-axis goniometer that supports the aforementioned radiation thermometer.

[0013] In the single crystal silicon manufacturing apparatus, the aforementioned adjustment device can be a two-axis goniometer that supports the aforementioned radiation thermometer.

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

[0015] In the single crystal silicon manufacturing apparatus, the aforementioned adjustment device can be a two-axis goniometer that supports the aforementioned radiation thermometer.

[0016] In the single crystal silicon manufacturing apparatus, the aforementioned adjustment device can be a two-axis goniometer that supports the aforementioned radiation thermometer.

[0017] According to the present application, in a single crystal silicon manufacturing apparatus that measures the temperature of the surface of a silicon melt using a radiation thermometer, the position measured by the radiation thermometer can be accurately aligned with respect to a target position. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 is a longitudinal sectional view showing the schematic structure of a single crystal silicon manufacturing apparatus of an embodiment of the present application.

[0019] Figure 2 is a perspective view partially disassembling a radiation thermometer unit fixed at a pull-up cavity cover of an embodiment of the present application.

[0020] Figure 3 is a perspective view partially disassembling an adjustment apparatus of an embodiment of the present application.

[0021] Figure 4 is a side view partially sectioned showing the configuration of a radiation thermometer and a reflecting portion of an embodiment of the present application.

[0022] Figure 5 is a sectional view of a laser apparatus of an embodiment of the present application.

[0023] Figure 6A are plan and side views of a coordinate plate of an embodiment of the present application.

[0024] Figure 6B are plan and side views of a coordinate plate of an embodiment of the present application.

[0025] Figure 7 is a schematic view showing the fixed state of a coordinate plate in a round plate fixing process.

[0026] Figure 8 is a view showing the case where a pattern of a mark is projected onto a coordinate plate by diffused laser light in an irradiation process. DETAILED DESCRIPTION

[0027] Hereinafter, the present embodiment will be described with reference to the drawings.

[0028] Figure 1 is a longitudinal sectional view showing the schematic structure of a single crystal silicon manufacturing apparatus of an embodiment of the present application. The single crystal silicon manufacturing apparatus 1 manufactures a single crystal silicon SM by the CZ method.

[0029] As shown in Figure 1 , the single crystal silicon manufacturing apparatus 1 is provided with a cavity 50, a crucible 51, a heater 52, a pull-up portion 53, a heat shield 54, a heat insulating member 55, a crucible shaft 56, and a radiation thermometer unit 2.

[0030] The cavity 50 is provided with a main cavity 57 in which a crystal is pulled up, and a pull-up cavity 58 which is connected to the upper portion of the main cavity 57 and accommodates the crystal pulled up. The pull-up cavity 58 is provided with a gas introduction port 59 which introduces a non-active gas such as argon (Ar) into the main cavity 57. A gas discharge port (not shown) which discharges the gas in the main cavity 57 by driving of a vacuum pump is provided at the lower portion of the main cavity 57.

[0031] The pull-up chamber 58 has a cylindrical pull-up chamber main body 58A and a pull-up chamber cover 58B that seals the upper end of the pull-up chamber main body 58A. A measurement window 58C is provided at the pull-up chamber cover 58B. The measurement window 58C can be formed of a material that transmits radiation light from the silicon melt M, such as quartz. An observation window 57A for observing the inside of the main chamber 57 is provided at the main chamber 57.

[0032] The radiation thermometer unit 2 is fixed to the pull-up chamber cover 58B and measures the temperature of the measurement position of the silicon melt surface via the measurement window 58C. The distance from the radiation thermometer unit 2 to the silicon melt surface is about 6 m.

[0033] A maintenance platform 60 is provided at the upper portion of the pull-up chamber 58. An operator can perform work (adjustment, measurement, etc.) related to the radiation thermometer unit 2 on the maintenance platform 60.

[0034] The crucible 51 is disposed in the main chamber 57 and stores the silicon melt M.

[0035] The heater 52 is disposed at a predetermined interval outside the crucible 51 and heats the silicon melt M in the crucible 51. The pull-up portion 53 has a cable 61 having a seed crystal SC attached to one end, and a pull-up drive portion 62 that raises and rotates the cable 61.

[0036] The heat shield 54 is provided so as to surround the pulled single crystal silicon SM and cut off radiant heat from the heater 52 to the single crystal silicon 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 predetermined speed. In addition, the crucible 51 is detachably attached with respect to the crucible shaft 56, and the coordinate plate 35 described later can be detachably attached at the crucible shaft 56 instead of the crucible 51.

[0037] Next, the radiation thermometer unit 2 will be described.

[0038] The radiation thermometer unit 2 is a unit that has the radiation thermometer 3 that measures the temperature of the silicon melt surface in the crucible 51 at the time of manufacturing the single crystal silicon SM.

[0039] Figure 2 is an exploded perspective view of a portion of the radiation thermometer unit 2 fixed at the pull-up chamber cover 58B. In addition, Figure 2 is a state in which the laser device 5 is not attached to the radiation thermometer 3 so that the viewfinder 17 that enables observation of the radiation thermometer 3 is represented.

[0040] As Figure 2As shown, the radiation thermometer unit 2 is provided with a radiation thermometer 3 that non-contact measures the temperature of the surface of the silicon melt, an adjustment device 4 that adjusts the measurement position of the radiation thermometer 3, a laser device 5 that emits laser light, and a reflection portion 6. The reflection portion 6 reflects the optical path P of the radiation light measured by the radiation thermometer 3 and the laser light emitted from the laser device 5 in a direction orthogonal to the incident direction.

[0041] The viewfinder 17 of the radiation thermometer 3 is normally used in visual-based temperature measurement, but in the radiation thermometer unit 2 of the present application, the laser device 5 is installed at the viewfinder 17. The laser device 5 is a device that functions as a light source that supplies light such as laser light. The laser device 5 is installed at the viewfinder, and thus the laser device 5 emits laser light along an axis that coincides with the optical axis A of the lens 15 (see FIG. 2) of the radiation thermometer 3. This laser light is reflected in an orthogonal direction by the reflection portion 6 and is irradiated to the surface of the silicon melt M. On the other hand, the optical path P of the radiation light (infrared rays) from the silicon melt M measured by the radiation thermometer 3 is reflected in an orthogonal direction by the reflection portion 6 and is incident to the lens 15. Therefore, the optical path P coincides with the optical path of the laser light reflected by the reflection portion 6, and the irradiation position of the laser light corresponds to the measurement position of the radiation thermometer 3, so it can be used for adjustment of the measurement position of the radiation thermometer 3. Figure 4

[0042] The radiation thermometer 3 is fixed to the pull-up cavity cover 58B via the adjustment device 4. In the radiation thermometer unit 2 of the present embodiment, the radiation thermometer 3 is disposed so that the optical axis A of the lens 15 is substantially horizontal, and the optical path P is converted to a substantially vertical direction via the reflection portion 6.

[0043] Figure 3 is an exploded perspective view of a portion of the adjustment device 4. The adjustment device 4 is fixed to the pull-up cavity cover 58B and supports the radiation thermometer 3, and is a device that adjusts the measurement position of the radiation thermometer 3.

[0044] The adjustment device 4 is provided with a base plate 7 that is fixed to the pull-up cavity cover 58B, a two-axis goniometer stage 8 that is fixed to the base plate 7, and a seating plate 9 that supports the radiation thermometer 3 and is fixed to the two-axis goniometer stage 8.

[0045] The base plate 7 is, for example, a plate-shaped member that is fixed to the pull-up cavity cover 58B via a fastening link member such as a bolt B1 (see FIG. 2). 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-up cavity cover 58B so that the upper surface thereof is horizontal. The two-axis goniometer stage 8 is, for example, fixed to the upper surface of the base plate 7 via a bolt (not shown). Figure 2

[0046] ​​A plurality of stop bolts 10 can be installed to the base plate 7. The stop bolt 10 is a bolt having a shaft portion 10A that is threadedly engaged with an internally 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 contacts the lower surface of the placement plate 9.

[0047] The two-axis goniometer stage 8 is a device for adjusting the posture of the radiation thermometer 3 supported by the adjusting device 4. By adjusting the posture of the radiation thermometer 3 by means of the two-axis goniometer stage 8, the angle of the optical axis A of the lens 15 is adjusted, and the measurement position of the radiation thermometer 3 is adjusted.

[0048] The two-axis goniometer stage 8 combines two single-axis goniometer stages (tilt stages) in such a manner that the respective centers of rotation are 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.

[0049] 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 FIG. 2), 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 an axis parallel to the Y axis. Figure 3 ) parallel to the Y axis, 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 an axis parallel to the Y axis.

[0050] The second goniometer stage 12 has a second fixed stage 12A, a second movable stage 12B connected to the upper side of the second fixed stage 12A, and a second handle 12C. The upper surface of the second fixed stage 12A is a cylindrical curved surface centered on an axis parallel to the X axis (refer to FIG. 2), and the lower surface of the second movable stage 12B is along the curved surface of the upper surface of the second fixed stage 12A. By turning the second handle 12C, the second movable stage 12B is turned about an axis parallel to the X axis. Figure 3

[0051] Here, the X axis is an axis extending horizontally through the center of the cavity 50, and the Y axis is an axis extending in the horizontal direction orthogonally to the X axis.

[0052] The placement plate 9 is fixed to the upper surface of the second goniometer stage 12 by fastening link members such as bolts B2, and is a plate-like member disposed between the radiation thermometer 3 and the two-axis goniometer stage 8. The placement plate 9 can be formed of a plate having a strength sufficient to support the radiation thermometer 3. At the placement plate 9, a plurality of radiation thermometer fixing holes 9A used when the radiation thermometer 3 is fixed to the placement plate 9 are formed.

[0053] Next, the structure of the radiation thermometer 3 will be described. Figure 4 is a partially cutaway side view illustrating the configuration of the radiation thermometer 3 and the reflecting portion 6.​

[0054] As shown in Figure 4 Fig. 1, the radiation thermometer 3 is provided with a substantially cylindrical case 14, a lens 15 arranged in the case 14, a detection element 16 arranged in the case 14, and a viewfinder 17.

[0055] The lens 15 is arranged so that its optical axis A coincides with the central axis of the case 14. That is, by arranging the radiation thermometer 3 so that the central axis of the case 14 is horizontal, the optical axis A of the lens 15 can be made horizontal.

[0056] The radiation thermometer 3 is a radiation thermometer of a type that converges, to the detection element 16, the radiant light of the measurement target that is taken in through an opening portion 14A formed at the case 14, via the lens 15 and a beam splitter 18. The beam splitter 18 is used to separate the radiant light and the visible light, and for example, a half mirror can be used.

[0057] The detection element 16 is an element that senses the radiant light and generates an electric signal corresponding to the energy of the radiant light.

[0058] The radiation thermometer 3 has a mark (for example, a black circle) whose center coincides with the optical axis A of the lens 15. The mark is marked so that its center is the measurement center. The mark can be formed directly on the lens 15, but can also be formed outside the lens 15. Further, the distance coefficient of the radiation thermometer 3 is selected in correspondence with the measurement distance (for example, 6,000 mm in the present embodiment) and the size of the measurement target object.

[0059] Next, the reflection portion 6 will be described. The reflection portion 6 is a mechanism for bending the optical path P of the radiant light at right angles.

[0060] As shown in Figure 4 Fig. 2, the reflection portion 6 has a mirror case 30 that is fixed at the case 14 of the radiation thermometer 3, a mirror body 31 that is fixed in the mirror case 30, and a shield pipe 32 that is connected to the lower portion of the mirror case 30 and shields between the mirror case 30 and the measurement window 58C. In addition, when the radiation thermometer 3 is inclined by the two-axis goniometer stage 8, a slight gap is provided between the shield pipe 32 and the measurement window 58C so that the shield pipe 32 does not collide with the measurement window 58C.

[0061] The mirror case 30 is a case that houses the mirror body 31 at an appropriate angle with respect to the optical axis A of the lens 15. The mirror case 30 has a function of cutting off the light from the outside.

[0062] The mirror body 31 is formed of a material capable of reflecting radiated light (infrared rays) and laser light. The mirror body 31 can be formed of, for example, an aluminum evaporated mirror. The aluminum evaporated mirror has a wide wavelength band compared to a gold evaporated glass mirror in which a gold evaporated coating layer is applied to one surface of a quartz glass, and is also suitable for laser reflection. The mirror body 31 is not limited to the aluminum evaporated mirror, and can employ, for example, a gold evaporated mirror. The gold evaporated mirror has high reflectivity in an infrared wavelength, a near-infrared wavelength, and the like under optimum conditions, but silicon is known to have a wavelength of about 0.6 μm (600 nm) or less at around 600°C, and further has a short wavelength at a high temperature. The reflectivity of the aluminum evaporated mirror and the gold evaporated mirror is not greatly different in this region. Therefore, the inexpensive aluminum evaporated mirror can be used compared to the gold evaporated mirror.

[0063] The shield tube 32 is a cylindrical member connected to the lower portion of the mirror case 30. The shield tube 32 has a function of cutting off external light between the mirror case 30 and the measurement window 58C.

[0064] Next, the laser device 5 will be described. Figure 5 is a cross-sectional view of the laser device 5.

[0065] As shown in Figure 5 , the laser device 5 has a laser projector 19 (light source body) and a laser fixing jig 20 (light source fixing jig) for fixing the laser projector 19 to the finder 17 of the radiation thermometer 3. The laser projector 19 is fixed by the laser fixing jig 20 in such a manner that the axis B of the laser light coincides with the optical axis A of the lens 15. Thereby, the laser light emitted from the laser projector 19 is irradiated to the center of the measurement position (target) of the radiation thermometer 3 in a case where the pattern shape is set to a point pattern (light spot).

[0066] The laser projector 19 is a device that emits laser light to irradiate a laser pattern to an irradiation object. The laser projector 19 is in a cylindrical shape, and has a laser irradiation port 19A provided at one end. The laser projector 19 emits laser light in the axis direction of the laser projector 19.

[0067] The laser projector 19 can adjust the focal point by operating a focal point adjustment portion 19B to make the pattern shape a point pattern, an extended diffusion pattern. That is, the laser projector 19 has a focal point variable mechanism. The laser projector 19 can be supplied with power by, for example, a battery pack constituted by a plurality of batteries. The power supply of the laser projector 19 is performed via a cable 19C.

[0068] The laser projector 19 can employ, for example, an LDS series manufactured by TAKENAKA OPTONIC.

[0069] The laser fixing jig 20 has a cylindrical portion 21 that houses the laser projector 19, a connection nut 22 that is attached to one end of the cylindrical portion 21 and is fixed to the viewfinder 17 of the radiation thermometer 3, and a push nut 23 that blocks the other end of the cylindrical portion 21 and supports the other end of the laser projector 19.

[0070] The cylindrical portion 21 is a member that constitutes a cylinder and has a cylindrical portion main body 24, a ridge portion 25, a diameter expansion portion 26, and an adjustment opening portion 27. The cylindrical portion main body 24 has a cylindrical inner peripheral surface into which the laser projector 19 is fitted. The ridge portion 25 is formed on the inner peripheral surface of one end side of the cylindrical portion main body 24. The diameter expansion portion 26 is formed on the outer peripheral surface of one end of the cylindrical portion main body 24. The adjustment opening portion 27 penetrates between the outer peripheral surface and the inner peripheral surface of the cylindrical portion main body 24.

[0071] The ridge portion 25 is formed on the inner peripheral side of the cylindrical portion main body 24 so as to protrude over the entire circumference of the inner peripheral surface of the cylindrical portion main body 24. The ridge portion 25 is a portion that contacts the tip end of the laser projector 19 housed in the cylindrical portion 21 and restricts movement of the laser projector 19 in the axis B direction toward one end side (B1 direction) of the cylindrical portion main body 24.

[0072] The diameter expansion portion 26 is a portion in which the cylindrical portion main body 24 is expanded in diameter. The outer diameter of the diameter expansion portion 26 is slightly larger than the outer diameter of the cylindrical portion main body 24 and is a size that fits into the inner peripheral surface of the connection nut main body 22A described later. The surface of the diameter expansion portion 26 that faces the B2 direction and abuts against the connection nut 22 described later is a tapered surface 26A that constitutes a taper that gradually expands in diameter toward the B1 direction. The B2 direction is the direction on the side opposite to the B1 direction.

[0073] The adjustment opening portion 27 is an opening that can operate the focal point adjustment portion 19B of the laser projector 19 housed in the cylindrical portion 21.

[0074] The push nut 23 has a push nut main body 23A that is threadedly engaged with an external thread groove 24A formed on the outer peripheral surface of the cylindrical portion main body 24 and a nut ridge portion 23B formed on the inner peripheral surface of the push nut main body 23A. The nut ridge portion 23B is formed on the inner peripheral surface of the push nut main body 23A over the entire circumference.

[0075] The push nut 23 is a member that restricts movement of the laser projector 19 in the B1 direction.

[0076] Furthermore, the laser fixing jig 20 has a rubber ring 28 that is arranged between the laser projector 19 and the nut ridge portion 23B of the push nut 23 and functions as a cushion member.

[0077] The connection nut 22 is a member that holds the cylindrical portion 21 and is threadedly engaged with the viewfinder 17 of the radiation thermometer 3.

[0078] Specifically, the connection nut 22 is a combined nut having a connection nut main body 22A and a locking portion 22B, the connection nut main body 22A covering the enlarged diameter portion 26 of the barrel portion 21 from the outer peripheral side and being threadedly engaged with an external thread groove formed in the outer peripheral surface of the viewfinder 17 of the radiation thermometer 3, and the locking portion 22B being formed in the inner peripheral surface of the connection nut main body 22A and locking the enlarged diameter portion 26 from the side opposite to the viewfinder 17.

[0079] The locking portion 22B is formed over the entire circumference of the inner peripheral surface of the connection nut main body 22A. The inner diameter of the locking portion 22B is a size smaller than the outer diameter of the enlarged diameter portion 26 of the barrel portion 21 and slightly larger than the outer diameter of the barrel main body 24.

[0080] The surface of the locking portion 22B facing the Bl direction and abutting against the enlarged diameter portion 26 of the barrel portion 21 is a tapered surface 22C constituting a taper gradually expanding toward the Bl direction. The tapered surface 26A of the enlarged diameter portion 26 and the tapered surface 22C of the locking portion 22B are formed to be in surface contact with each other.

[0081] In this way, the barrel portion 21 and the connection nut 22 are in contact via the tapered surfaces 26A and 22C, whereby the reproducibility of the angle of the barrel portion 21 can be improved at the time of mounting and dismounting of the laser fixing jig 20. Thus, the reuse of the laser projector 19 and the laser fixing jig 20 becomes easy, and it is possible to use one laser projector 19 in a plurality of single-crystal silicon manufacturing devices 1 as needed only at the time of adjustment of the measurement position of the radiation thermometer 3, so that cost reduction can be achieved.

[0082] Further, the barrel portion 21 and the connection nut 22 are in contact via the tapered surfaces 26A and 22C, whereby in the case where the axis B of the laser light and the optical axis A of the lens 15 are not coincident, the angle of the barrel portion 21 can be easily finely adjusted.

[0083] The laser fixing jig 20 has a ring member 29 disposed between the end surface of the barrel portion 21 and the viewfinder 17 at the time of mounting the laser projector 19 to the radiation thermometer 3 with the laser fixing jig 20. The ring member 29 is formed to have an outer diameter substantially the same as the outer diameter of the enlarged diameter portion 26 of the barrel portion 21 and an inner diameter substantially the same as the inner diameter of the barrel main body 24. The ring member 29 is formed of, for example, a resin such as polytetrafluoroethylene (PTFE).

[0084] Next, the mounting method of the laser projector 19 with the laser fixing jig 20 will be described.

[0085] First, the ring member 29 is attached to the end surface of the cylindrical portion 21 on the B1 direction side by means of an adhesive so that the inner peripheral surface of the cylindrical portion 21 and the inner peripheral surface of the ring member 29 do not deviate. Next, the cylindrical portion 21 is inserted into the connecting nut 22, and the connecting nut 22 and the cylindrical portion 21 are combined.

[0086] Next, the laser projector 19 is inserted into the inside of the cylindrical portion 21. Next, after the rubber ring 28 is attached to the push nut 23, the push nut 23 is installed to the cylindrical portion 21. With the above, the laser fixing jig 20 in which the laser projector 19 is installed is assembled.

[0087] Then, the connecting nut 22 of the laser fixing jig 20 is installed to the viewfinder 17 of the radiation thermometer 3. By this, the laser projector 19 is installed to the radiation thermometer 3.

[0088] Next, the coordinate plate 35 used when adjusting the measurement position of the radiation thermometer 3 by 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 imitates the surface of the silicon melt when adjusting the measurement position of the radiation thermometer 3.

[0089] Figure 6A and Figure 6B are a plan view and a side view of the coordinate plate 35. As shown in Figure 6A and Figure 6B , the coordinate plate 35 is a member configured in a circular plate shape. The coordinate plate 35 is fixed to the upper end of the crucible shaft 56 with its main surface horizontal.

[0090] Preferably, the coordinate plate 35 is formed of a material such as a resin such as polytetrafluoroethylene that is not problematic even if it comes into contact with the crucible shaft 56.

[0091] The coordinate plate 35 is formed with a pattern that functions as a coordinate when recording a target position by groove processing on one surface. As the pattern, there can be a lattice-shaped pattern Figure 6A , or a pattern Figure 6B composed of a plurality of circles in a concentric circle shape and a plurality of lines extending radially from the center. Furthermore, each of these patterns can be formed on the front surface and the back surface of the coordinate plate 35, respectively.

[0092] Next, the method of adjusting the temperature measurement position using the single crystal silicon manufacturing device 1 described above will be described.

[0093] The method of manufacturing single crystal silicon has a target position determining step, a coordinate plate fixing step, an irradiation step, and an adjustment step.

[0094] The target position determining step is a step of determining a target position of the surface of the silicon melt at which effective crystal quality control can be performed by measuring the temperature.

[0095] In the target position determining step, for example, the temperature distribution of the silicon melt surface measured by the two-dimensional thermometer is measured. Next, a low-temperature region that remains low in temperature compared to other regions is specified based on the temperature of the measured temperature distribution. Next, the target position is set inside the low-temperature region.

[0096] In the coordinate plate fixing step, as shown in FIG. 6, the coordinate plate 35 is attached to the upper end of the crucible shaft 56 in a state where the crucible 51 is removed. Next, the crucible shaft 56 is moved up and down, whereby the coordinate plate 35 is moved so that the upper surface of the coordinate plate 35 is the same height as the silicon melt surface. Figure 7

[0097] The irradiation step is performed after the radiation thermometer unit 2 is attached to the pulling chamber 58. Power is supplied to the laser device 5, and the focal point variable mechanism is operated to irradiate the diffused laser light toward the coordinate plate 35. As shown in FIG. 7, the marks of the radiation thermometer 3 are projected onto the coordinate plate 35 according to the pattern LP of the diffused laser light. Here, in the case where the axis B of the laser light (refer to FIG. 8) does not coincide with the optical axis A of the lens 15 (refer to FIG. 9), that is, in the case where the projected marks are not located at the center of the pattern LP of the diffused laser light, the angle of the barrel portion 21 of the laser fixing jig 20 is finely adjusted. Figure 8 Figure 5 Figure 4

[0098] In the adjustment step, the adjustment device 4 is operated so that the target position determined in the target position determining step coincides with the center of the projected marks. At this time, it is preferable that an operator who observes the coordinate plate 35 through the observation window 57A be arranged in addition to the operator on the maintenance platform 60.

[0099] Specifically, first, the head of the stop bolt 10 that initially contacts the lower surface of the seating plate 9 is lowered by screwing the threads of the stop bolt 10 into the base plate 7 to be separated from the lower surface of the seating plate 9 by about 5 to 10 mm. Next, the first handle 11C of the two-axis goniometer stand 8 is rotated, whereby the radiation thermometer 3 is rotated about the axis along the Y axis, and the second handle 12C is rotated, whereby the radiation thermometer 3 is rotated about the axis along the X axis. By using the two-axis goniometer stand 8, for example, by applying a tilt of 0.1°, the measurement position separated by 6 m is moved by about 10.5 mm (tan 0.1° x 6, 000 mm). Thus, the measurement position of the radiation thermometer 3 can be finely adjusted.

[0100] After the adjustment to the target position is completed, the head of the stop bolt 10 is raised by loosening the screwing of the stop bolt 10 from the base plate 7. When the lower surface of the seating plate 9 is contacted, the two hexagonal nuts 10C arranged between the stop bolt 10 and the base plate 7 are tightened to the base plate 7 side, whereby the height of the stop bolt 10 is fixed. ​​​​

[0101] Next, the coordinate plate 35 is removed from the crucible shaft 56, and the crucible 51 is installed. Further, the laser fixing jig 20 is removed from the viewfinder 17.

[0102] By the above procedure, the measurement position of the radiation thermometer 3 can be accurately aligned with respect to the target position. Thus, the temperature measurement of the silicon melt surface can be performed at the desired position while the single crystal silicon is pulled up.

[0103] Further, the two-axis goniometer 8 is used as the adjustment device 4, whereby fine adjustment of the measurement position of the radiation thermometer 3 can be performed. Furthermore, the measurement position of the radiation thermometer 3 is changed only by the angle adjustment of the two-axis goniometer 8, so it is not necessary to fasten the bolts of the fixing seating plate 9 or the like after adjustment, and the measurement position does not change.

[0104] Further, after adjustment of the two-axis goniometer 8, the stop bolt 10 is fixed in a state where the head of the stop bolt 10 contacts the lower surface of the seating plate 9, whereby the change in the temperature measurement position due to the change over time or mechanical micro-vibration or the like occurring in the single crystal silicon manufacturing device 1 can be suppressed.

[0105] Further, the setting of the goniometer on the horizontal plane is recommended, so by being configured to reflect the optical path P of the radiation light in the orthogonal direction by the reflection portion 6, adjustment work using the two-axis goniometer 8 can be performed. Further, by the combination of the reflection portion 6 and the two-axis goniometer 8, work on the maintenance platform 60 can be performed, and the adjustment work can be facilitated.

[0106] Further, an aluminum evaporation mirror is used as the mirror of the reflection portion 6, whereby not only the radiation light but also laser light can be set as the reflection portion 6 suitable for the reflection of the laser light.

[0107] Further, with respect to the laser light to be irradiated, the configuration is such that the mark is projected by the diffused laser light, whereby the mark that accurately coincides with the mark can be effectively utilized, and the accuracy of adjustment can be improved.

[0108] Further, as the laser projector 19, a laser projector that can be supplied with power by a battery pack composed of a plurality of batteries is used, whereby the portability of the laser projector 19 is improved, and work at a high place can be facilitated.

[0109] Further, during the adjustment procedure, the coordinate plate 35 that functions as an imaginary liquid surface imitating the surface of the silicon melt is used, whereby the measurement position of the mark projected to the coordinate plate 35 by the laser light can be accurately grasped, and the measurement position can be accurately aligned with the target position.

[0110] [Modified Example]

[0111] The present application is not limited to the above-described configuration, and variations within the scope of the present application are included.

[0112] In the above-described embodiment, the laser device 5 provided with the laser projector 19 is used as the light source, but is not limited thereto, and any light source having a certain degree of straight progressiveness in light can be used. For example, a light source such as an LED light source can be used.

[0113] In the above-described embodiment, the biaxial goniometer stage is used as the adjustment device 4, but any device capable of adjusting the measurement position of the emission thermometer 3 can be used. For example, a stage device having a configuration in which the X-axis, Y-axis, and θ-axis are independent of each other can be used as the adjustment device 4.

[0114] Further, in the above-described embodiment, the pattern shape of the laser light emitted from the laser projector 19 is a diffusion pattern, but can be a point pattern. Thus, the present application can be applied to an emission thermometer having no marker.

[0115] Further, in the above-described embodiment, the reflection portion 6 is provided to reflect the radiation light, but is not limited thereto, and the emission thermometer 3 can be directly exposed to the radiation light. For example, an L-shaped bracket is mounted on the biaxial goniometer stage, and the emission thermometer 3 is mounted at the L-shaped bracket such that the optical axis is in the vertical direction, whereby the reflection portion 6 can be omitted.

[0116] Further, the coordinate plate 35 need not be a circular plate, and can be a polygonal shape. The marker provided at the emission thermometer 3 is not limited to a black circle, and the shape and color thereof can be appropriately set.

Claims

1. A single crystal silicon manufacturing apparatus characterized by comprising a chamber, a crucible, a radiation thermometer, a laser device that emits laser light, an adjustment device, the crucible is disposed in the chamber, the radiation thermometer has a detection element that detects radiation light from a measurement object, a lens that condenses the radiation light to the detection element, a viewfinder that visually confirms the measurement object, and a beam splitter that separates the radiation light and visible light, the laser device emits laser light to the measurement object via the viewfinder and the lens along an axis that coincides with an optical axis of the lens, the adjustment device supports the radiation thermometer in a state where a measurement position of the radiation thermometer can be adjusted, the radiation thermometer has a mark whose center coincides with the optical axis of the lens, the laser device has a focal point variable mechanism.

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

3. The single crystal silicon manufacturing apparatus according to claim 2, characterized in that, having a base plate, a seating plate, a nut, a plurality of set screws, the base plate supports the two-axis goniometer, the seating plate is disposed between the radiation thermometer and the two-axis goniometer, the plurality of set screws have a shaft portion that is threadedly engaged with an internally threaded hole formed at the base plate, and a head portion that is in contact with a lower surface of the seating plate, the nut fixes a height of the set screws.

4. The single crystal silicon manufacturing apparatus according to any one of claims 1 to 3, characterized in that, having a reflection portion that reflects an optical path of radiation light measured by the radiation thermometer and light supplied from the laser device to an orthogonal direction with respect to an incident direction.

5. The single crystal silicon manufacturing apparatus according to claim 4, characterized in that, the reflection portion has a mirror main body formed of an aluminum evaporation mirror.

6. The single crystal silicon manufacturing apparatus according to any one of claims 1 to 3, characterized in that, comprising a crucible shaft and a coordinate plate, the crucible shaft rotatably and vertically movably supports the crucible, the coordinate plate is removably attached to the crucible shaft, and is irradiated with light supplied from the laser device.

7. The single crystal silicon manufacturing apparatus according to any one of claims 1 to 3, characterized in that, the laser device has a light source main body, and a light source fixing jig that fixes the light source main body to the viewfinder, the light source fixing jig comprises a barrel portion and a connecting nut, the barrel portion houses the light source main body, the connecting nut connects the barrel portion and the viewfinder, the barrel portion has a barrel portion main body that is cylindrical and houses the light source main body, and an enlarged diameter portion that is formed on an outer circumferential surface of an end portion of the barrel portion main body, the connecting nut has a connecting nut main body that covers the enlarged diameter portion from an outer circumferential side, and a locking portion that is formed on an inner circumferential surface of the connecting nut main body and locks the enlarged diameter portion from a side opposite to the viewfinder. ​ The diameter-expanding portion and the locking portion are formed to be in contact via a tapered surface that expands in diameter toward the finder side.

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