Exhaust device, silicon single crystal manufacturing device, exhaust method, and manufacturing method of silicon single crystal

Abstract

To provide a device for safely and continuously removing a deposit of a silicon oxide (SiOx) produced in an exhaust pipe in lifting a silicon single crystal with a CZ method without opening the exhaust pipe.SOLUTION: An exhaust device is connected to a silicon single crystal lifting device that includes a chamber and a quartz crucible in the chamber and lifts a silicon single crystal from a raw material melt accommodated in the quartz crucible. The exhaust device includes: an exhaust pipe that is connected to the chamber and exhausts an inert gas introduced to the chamber; a water supply device that is connected to the exhaust pipe and supplies water to the exhaust pipe for removing a deposit deposited in the exhaust pipe; and a storage tank that is connected to the exhaust pipe, stores the water exhausted from the exhaust pipe, and removes the deposit contained in the water by precipitation.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an exhaust device, a silicon single crystal manufacturing apparatus, an exhaust method, and a silicon single crystal manufacturing method. [Background technology]

[0002] The Czochralski method (hereinafter referred to as the "CZ method"), in which a single crystal is grown from silicon melt in a quartz crucible inserted into a graphite crucible, is widely used as a method for producing silicon single crystals used in the manufacture of semiconductor devices.

[0003] In the CZ method, polycrystalline silicon raw material packed in a quartz crucible is heated and melted using a cylindrical graphite heater in an inert gas atmosphere, and a seed crystal is immersed in the molten silicon and pulled up while rotating the quartz crucible and seed crystal to produce a silicon single crystal.

[0004] When pulling a single crystal, oxygen dissolves from the inner surface of the quartz crucible into the molten silicon, reacts with the molten silicon to produce silicon oxide (SiOx), which evaporates from the surface of the molten silicon.

[0005] In the CZ method, silicon oxide that evaporates from the surface of the molten liquid precipitates on the chamber walls directly above the molten liquid, and if it falls onto the molten liquid surface it will inhibit single crystal growth. Therefore, the chamber is vacuum pumped to a low pressure of several thousand Pa and an inert gas is circulated to expel the evaporating silicon oxide from the furnace. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2001-097797 Summary of the Invention [Problem to be solved by the invention]

[0007] Silicon oxide gas is discharged from the furnace and reaches the exhaust gas pipe (hereinafter also referred to as the "exhaust pipe"; an exhaust gas pipe that connects multiple silicon single crystal pulling devices to a single exhaust gas pipe is also called the "exhaust gas collection pipe"), where it gradually cools and precipitates and accumulates on the inner surface of the exhaust gas pipe. Because there is not enough oxygen in the molten liquid or the furnace, this silicon oxide is not completely oxidized and accumulates in an unstable, partially oxidized state such as SiOx. Because it exists in the unstable, partially oxidized form of SiOx, the introduction of air can cause rapid oxidation, which can lead to small localized fires, creating a dangerous situation.

[0008] Because the CZ method is a batch process, when pulling is complete, the equipment must be opened to remove the remaining raw material and the quartz crucible, and silicon oxide that has adhered to the inside of the furnace and exhaust gas pipe must be removed.When removing the silicon oxide that has adhered to the inside of the exhaust gas pipe by suction, there is a possibility of a small, localized fire, so a small amount of air is allowed to flow to promote the oxidation of the adhesions before opening the equipment.

[0009] Before the equipment is opened, air is temporarily introduced into the exhaust gas collection pipe, which occasionally causes small localized fires and damages parts of the pipe. Measures to prevent damage to the pipes have been taken, such as installing burst valves and pressure relief valves, but in recent years, the amount of silicon oxide that accumulates has increased with the increase in the weight of single crystals and improvements in melting methods, and this has led to the problem of an increasing number of small localized fires.

[0010] Furthermore, since large amounts of silicon oxide discharged from each lifting machine adhere to the exhaust gas collection pipe, the exhaust gas collection pipe must be periodically opened to clean and remove the silicon oxide, which increases the risk of small localized fires when the pipe is opened.

[0011] The present invention has been made to solve the above problems, and aims to provide an apparatus that safely and continuously removes silicon oxide (SiOx) deposits that are generated in an exhaust pipe during pulling of silicon single crystals by the CZ method, without opening the exhaust gas pipe. [Means for solving the problem]

[0012] The present invention has been made to achieve the above-mentioned object, and provides an exhaust device connected to a silicon single crystal pulling device that includes a chamber and a quartz crucible in the chamber and that pulls up a silicon single crystal from a raw material melt contained in the quartz crucible, the exhaust device comprising: an exhaust pipe connected to the chamber for exhausting an inert gas introduced into the chamber; a water supply device connected to the exhaust pipe for supplying water to the exhaust pipe for removing deposits that accumulate inside the exhaust pipe; and a storage tank connected to the exhaust pipe for storing the water drained from the exhaust pipe and for precipitating and removing the deposits contained in the water.

[0013] Such an exhaust system can promote and stabilize the oxidation of silicon oxide (SiOx) generated inside the exhaust pipe when pulling silicon single crystals using the CZ method, and can also remove silicon oxide deposits without opening the exhaust pipe, thereby reducing the risk of small, localized fires inside the exhaust pipe that may occur when cleaning the inside of the exhaust pipe or dismantling the equipment, and making it possible to safely remove deposits continuously without opening the exhaust pipe.

[0014] In this case, the storage tank may have a cone-shaped bottom and be provided with a drain valve at the bottom.

[0015] This makes it possible to easily remove any deposits that settle in the storage tank.

[0016] In this case, the water supply device may be connected to the storage tank, and the supernatant water supplied from the storage tank may be circulated and supplied to the exhaust pipe.

[0017] This makes it possible to reduce the amount of water consumed.

[0018] In this case, the water supply device may supply water to the exhaust pipe by spraying mist.

[0019] This increases the humidity in the exhaust pipe, further reducing the risk of minor fires.

[0020] In this case, the silicon single crystal manufacturing apparatus can be provided with the silicon single crystal pulling apparatus and the exhaust apparatus.

[0021] This makes it possible to produce silicon single crystals while reducing the risk of small localized fires in the exhaust pipe when pulling silicon single crystals by the CZ method.

[0022] In this case, an exhaust method using an exhaust device connected to a silicon single crystal pulling apparatus that includes a chamber and a quartz crucible in the chamber and pulls up a silicon single crystal from a raw material melt contained in the quartz crucible can be provided, characterized in that the exhaust method uses the above-mentioned exhaust device as the exhaust device, supplies water to the exhaust pipe to remove deposits that have accumulated in the exhaust pipe, stores the water drained from the exhaust pipe, and allows the deposits contained in the water to settle and be removed.

[0023] According to this exhaust method, when pulling silicon single crystals by the CZ method, it is possible to promote and stabilize the oxidation of silicon oxide (SiOx) generated inside the exhaust pipe, and also to remove silicon oxide deposits without opening the exhaust pipe, thereby reducing the risk of small localized fires inside the exhaust pipe that may occur when cleaning the inside of the exhaust pipe or dismantling the equipment, and making it possible to safely remove deposits continuously without opening the exhaust pipe.

[0024] At this time, the supernatant water of the stored water can be circulated and supplied to the exhaust pipe.

[0025] This reduces water consumption.

[0026] At this time, the water can be supplied by mist spraying.

[0027] This increases the humidity inside the exhaust pipe, further reducing the risk of small fires.

[0028] In this case, a method for producing a silicon single crystal can be provided, characterized in that the silicon single crystal is produced using the silicon single crystal production apparatus.

[0029] This makes it possible to produce silicon single crystals while reducing the risk of small localized fires in the exhaust pipe when pulling silicon single crystals by the CZ method. [Effects of the Invention]

[0030] As described above, the exhaust system of the present invention can promote and stabilize the oxidation of silicon oxide (SiOx) generated inside the exhaust pipe when pulling silicon single crystals by the CZ method, and can also remove silicon oxide deposits without opening the exhaust pipe, thereby reducing the risk of small, localized fires inside the exhaust pipe that may occur when cleaning the inside of the exhaust pipe or dismantling the equipment, and making it possible to safely remove deposits continuously without opening the exhaust pipe. [Brief explanation of the drawings]

[0031] [Figure 1] 1 shows a schematic diagram of an example of an exhaust device of the present invention. [Figure 2] 1 shows a schematic diagram of an example of a silicon single crystal pulling apparatus according to the present invention. [Figure 3] FIG. 2 is a schematic diagram of an example of another embodiment of the exhaust device of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0032] The present invention will be described in detail below, but the present invention is not limited thereto.

[0033] As mentioned above, there was a need for a device that could safely and continuously remove the silicon oxide (SiOx) deposits that form inside the exhaust pipe when pulling silicon single crystals using the CZ method, without opening the exhaust gas pipe.

[0034] The inventors of the present invention have conducted extensive research into the above-mentioned problems and have found that an exhaust system connected to a silicon single crystal pulling apparatus includes a chamber and a quartz crucible in the chamber, and the exhaust system is connected to a silicon single crystal pulling apparatus that pulls a silicon single crystal from a raw material melt contained in the quartz crucible, the exhaust system comprising: an exhaust pipe connected to the chamber and for exhausting an inert gas introduced into the chamber; a water supply system connected to the exhaust pipe and for supplying water to the exhaust pipe for removing deposits that accumulate in the exhaust pipe; and a storage tank connected to the exhaust pipe and for storing the water drained from the exhaust pipe and for precipitating and removing the deposits contained in the water. The exhaust system can promote and stabilize the oxidation of silicon oxide (SiOx) generated in the exhaust pipe when pulling a silicon single crystal by the CZ method, and can remove silicon oxide deposits without opening the exhaust pipe, thereby reducing the risk of small localized fires in the exhaust pipe that occur when cleaning the inside of the exhaust pipe or dismantling the apparatus, and enabling safe continuous removal of deposits without opening the exhaust pipe, thereby completing the present invention.

[0035] (Silicon single crystal pulling equipment) FIG. 2 shows a schematic diagram of an example of a silicon single crystal pulling apparatus connected to the exhaust system of the present invention. 2 is a silicon single crystal pulling apparatus that includes a chamber 6 and a quartz crucible 3 in the chamber 6, and that pulls a silicon single crystal 11 from a raw material melt (silicon melt) 2 contained in the quartz crucible 3. The silicon single crystal pulling apparatus 30 may further include a graphite crucible 4 that supports the quartz crucible 3, a lower shaft 12 that supports the crucibles 3, 4, and a graphite heater 5 that is provided on the outer periphery of the graphite crucible 4 and that heats and melts the raw material polycrystalline silicon. Furthermore, a seed crystal 10 for pulling the silicon single crystal 11 may be provided in the upper part of the chamber 6.

[0036] The silicon single crystal 11 is pulled by the CZ method using the silicon single crystal pulling apparatus 30 by filling the quartz crucible 3 with raw polycrystalline silicon, heating the graphite crucible 4 with the graphite heater 5 to melt the polycrystalline silicon, immersing the seed crystal 10 in the silicon melt 2, and pulling the seed crystal 10 out of the silicon melt 2 while rotating the quartz crucible 3 and the seed crystal 10 in opposite directions to grow the silicon single crystal 11 to a desired diameter and length.

[0037] During pulling of the silicon single crystal 11, an inert gas such as argon is introduced from the top of the chamber 6 to remove reaction products such as silicon oxides and prevent contamination of the silicon single crystal 11, and the gas is exhausted through an exhaust pipe 8 provided at the bottom end of the chamber 6. The exhaust pipe 8 constitutes part of the exhaust device 1, which will be described later, and is connected to the exhaust pipe 8 or exhaust gas collecting pipe 9 shown in FIGS. 1 and 3 at a connection part 31. The exhaust pipe 8 may be equipped with a vacuum pump 7 for adjusting the pressure inside the chamber 6.

[0038] (Exhaust system) The exhaust system of the present invention will be described below with reference to FIGS. The exhaust system of the present invention is connected to the silicon single crystal pulling apparatus described above. Figure 1 shows a schematic diagram of an example of the exhaust system of the present invention.

[0039] As shown in FIG. 1, the exhaust system 1 of the present invention includes an exhaust pipe 8 connected to a chamber 6 for exhausting the inert gas introduced into the chamber 6, a water supply device 21 connected to the exhaust pipe 8 for supplying water 24 to the exhaust pipe 8 for removing deposits that accumulate inside the exhaust pipe 8, and a storage tank 20 connected to the exhaust pipe 8 for storing the water 24 drained from the exhaust pipe 8 and for precipitating and removing the deposits contained in the water 24.

[0040] The exhaust gas emitted in the silicon single crystal manufacturing process contains silicon oxide gas, which gradually cools upon reaching the exhaust pipe, depositing and accumulating on the inner surface of the exhaust pipe. Because there is not enough oxygen in the molten liquid or the furnace, this silicon oxide is not completely oxidized and accumulates in an unstable, partially oxidized state such as SiOx. The exhaust device 1 of the present invention is characterized by passing water through the exhaust pipe 8, thereby accelerating the oxidation of the silicon oxide adhering and accumulating inside the exhaust pipe 8 and converting it to a less reactive SiO2 state. Reaction: 2SiO +H2O → 2SiO2+H2 In the above reaction formula, the coefficients for H2O and H2 are not specified because SiO is an incomplete substance.

[0041] This makes it possible to promote and stabilize the oxidation of silicon oxide (SiOx) that forms inside the exhaust pipe when pulling silicon single crystals using the CZ method. Also, by making it possible to remove silicon oxide deposits without opening the exhaust pipe, it reduces the risk of small localized fires inside the exhaust pipe that occur when cleaning the inside of the exhaust pipe or dismantling the equipment, and it makes it possible to safely remove deposits continuously without opening the exhaust pipe.

[0042] The water supply device 21 is not particularly limited, and may be any device that can be connected to the exhaust pipe 8 and has the function of supplying water to the exhaust pipe 8.

[0043] From the perspective of removing sediments by passing water through it, it is preferable that the water-passing portion of the exhaust pipe 8 has a gradient of 0.5 to 1.5% so that the drain outlet (not shown) that drains water into the storage tank 20 is at the bottom. If the gradient is 0.5 to 1.5%, water and sediments will flow easily together, reducing water consumption. Furthermore, when the factory is shut down for periodic maintenance or other reasons, repeatedly filling the exhaust pipe 8 with water and then draining it makes it easier to remove sediments more safely without opening the exhaust pipe 8.

[0044] The material of the exhaust pipe 8 is not particularly limited, but can be stainless steel, PVC pipe, etc. The diameter is also not particularly limited, but can be 150 to 300 mm.

[0045] The water 24 that flows through the exhaust pipe 8 is stored in a storage tank 20 installed downstream of the pipe. The storage tank 20 has a cone-shaped bottom and can be provided with a water drain valve 25 at the very bottom. This allows sediments that have settled at the bottom of the storage tank 20 to be easily removed by periodically draining the water from the bottom.

[0046] The water supply device 21 preferably supplies water 24 by mist spray to the exhaust pipe 8, particularly to the connection portion 31 with the silicon single crystal pulling apparatus. This prevents the powder from scattering due to wetting by passing water, further reducing the risk of small localized fires. The greater the water flow rate, the greater the amount of sediment that can be removed, but a flow rate of 1 to 10 L / min is preferable because it effectively prevents the drain pipe from clogging due to sediment collecting downstream.

[0047] In another embodiment of the exhaust system 1 of the present invention, as shown in Fig. 3, the water supply system 21 is connected to the storage tank 20, and the supernatant water 24A supplied from the storage tank 20 can be circulated and supplied to the exhaust pipe 8. In this case, the water supply system 21 can also be called a circulation tank, and the storage tank can also be called a buffer tank.

[0048] In this embodiment, the supernatant water 24A that overflows from the storage tank 20 is sent to the water supply device 21 and circulated back to the exhaust pipe 8, thereby reducing the amount of water consumed. For circulating the water, the exhaust device 1 may be equipped with a circulation pump 23.

[0049] In the exhaust system 1 of the present invention, the exhaust pipe 8 may be an exhaust pipe to which only one silicon single crystal pulling apparatus 30 is connected, but it is also preferable that the exhaust pipe 8 be an exhaust gas collection pipe 9 to which multiple silicon single crystal pulling apparatuses 30 [30A1 to An (n≧2)] are connected.

[0050] This allows the processing of deposits to be carried out simultaneously when pulling silicon single crystals using a plurality of silicon single crystal pulling apparatuses 30 [30A1 to An (n≧2)], thereby improving productivity.

[0051] (Silicon single crystal manufacturing equipment) The present invention can also be applied to a silicon single crystal manufacturing apparatus equipped with the above-mentioned silicon single crystal pulling apparatus and exhaust device, for example, a silicon single crystal manufacturing apparatus 40 as shown in FIGS.

[0052] This makes it possible to promote and stabilize the oxidation of silicon oxide (SiOx) that forms inside the exhaust pipe when pulling silicon single crystals using the CZ method. Also, by making it possible to remove silicon oxide deposits without opening the exhaust pipe, it reduces the risk of small localized fires inside the exhaust pipe that occur when cleaning the inside of the exhaust pipe or dismantling the equipment, and it makes it possible to safely remove deposits continuously without opening the exhaust pipe.

[0053] (Exhaust method) The present invention further provides an exhaust method using an exhaust device connected to a silicon single crystal pulling apparatus 30 that includes a chamber 6 and a quartz crucible 3 in the chamber 6 and pulls up a silicon single crystal 11 from a raw material melt 2 contained in the quartz crucible 3, the exhaust method comprising the steps of: using the above-described exhaust device 1 as the exhaust device; supplying water 24 to an exhaust pipe 8 to remove deposits that have accumulated in the exhaust pipe 8; storing the water 24 drained from the exhaust pipe 8; and removing the deposits contained in the water 24 by precipitating them.

[0054] According to this exhaust method, when pulling silicon single crystals by the CZ method, it is possible to promote and stabilize the oxidation of silicon oxide (SiOx) generated inside the exhaust pipe, and also to remove silicon oxide deposits without opening the exhaust pipe, thereby reducing the risk of small localized fires inside the exhaust pipe that may occur when cleaning the inside of the exhaust pipe or dismantling the equipment, and making it possible to safely remove deposits continuously without opening the exhaust pipe.

[0055] At this time, the water can be supplied by mist injection to the exhaust pipe 8, particularly to the connection portion 31 with the silicon single crystal pulling apparatus. This prevents the powder from scattering due to wetting by passing water, further reducing the risk of small localized fires. The greater the water flow rate, the greater the amount of sediment that can be removed, but a flow rate in the range of 1 to 10 L / min is preferable because it effectively prevents the drain pipe from clogging due to sediment collecting downstream.

[0056] At this time, the supernatant water 24A of the stored water can be circulated and supplied to the exhaust pipe 8 using the exhaust device 1 of the other embodiment described above. This reduces water consumption.

[0057] For circulation, a circulation pump 23 may be used. When the amount of water to be circulated becomes low, makeup water 22 can be added to the water supply device 21 as needed.

[0058] The exhaust pipe 8 may be an exhaust pipe to which only one silicon single crystal pulling apparatus 30 is connected, but it is also preferable to use an exhaust gas collection pipe 9 to which multiple silicon single crystal pulling apparatuses 30 [30A1 to An (n≧2)] are connected.

[0059] This allows the processing of deposits to be carried out simultaneously when pulling silicon single crystals using a plurality of silicon single crystal pulling apparatuses 30 [30A1 to An (n≧2)], thereby improving productivity.

[0060] (Silicon single crystal manufacturing method) The present invention also provides a method for producing a silicon single crystal, characterized in that a silicon single crystal is produced using the silicon single crystal production apparatus described above. This makes it possible to produce silicon single crystals while reducing the risk of small localized fires in the exhaust pipe when pulling silicon single crystals by the CZ method. [Example]

[0061] The present invention will be specifically explained below with reference to examples, but the present invention is not limited to these examples.

[0062] (Comparative Example) The exhaust pipes of 12 silicon single crystal pulling devices as shown in Figure 2 were connected to a stainless steel exhaust gas collection pipe with a diameter of 250A (effective inner diameter 259.4 mm (Sch100s)) and a length of 27 m, and silicon single crystals were produced using the devices.

[0063] When dismantling a silicon single crystal pulling device, the air introduction was limited to one device to prevent a large amount of air from flowing into the exhaust gas collection piping. Operations continued for one year, but four small localized fires occurred during that year.

[0064] In addition, there was a limit on the number of air intakes when the lifting machine was being dismantled, which resulted in waiting times when multiple dismantlings were being performed at the same time, reducing productivity.

[0065] (Example) Silicon single crystals were produced using an exhaust system as shown in Figure 3, in which the exhaust pipes of 12 silicon single crystal pulling devices as shown in Figure 2 were connected to a stainless steel exhaust gas collection pipe with a diameter of 250A (effective inner diameter 259.4 mm (Sch100s)) and a length of 27 m. The exhaust gas collection pipe was installed at a slope of 1 / 100 (0.57°) so that the drain outlet for discharging the water into the storage tank 20 was at the bottom.

[0066] A storage tank 20 with a volume of approximately 100 L and a water supply device 21 were installed, and water was circulated within the exhaust device 1 at a rate of approximately 5 L / min using a circulation pump 23. The water supply device 21 was equipped with an electrode-type level gauge, and when the water level dropped, a solenoid valve for makeup water opened to supply water, and when the water level rose, the water supply was controlled to stop, so that the water level was maintained within a certain range. The bottom of the storage tank was shaped like a mortar with a 45° slope, and a drain valve was installed at the very bottom, allowing settled sediment to be discharged.

[0067] The plant has been in operation for a year, but no small localized fires have occurred and the plant has been able to operate safely.

[0068] As described above, according to the embodiment of the present invention, in the production of silicon single crystals by the CZ method, it was possible to remove deposits of silicon oxide (SiOx) generated in the exhaust gas pipe without causing small localized fires when dismantling the production equipment.

[0069] The present specification includes the following aspects. [1]: An exhaust device that includes a chamber and a quartz crucible in the chamber, and is connected to a silicon single crystal pulling device that pulls a silicon single crystal from a raw material melt contained in the quartz crucible, the exhaust device including: an exhaust pipe connected to the chamber for exhausting an inert gas introduced into the chamber; a water supply device connected to the exhaust pipe for supplying water to the exhaust pipe for removing deposits that accumulate inside the exhaust pipe; and a storage tank connected to the exhaust pipe for storing the water drained from the exhaust pipe and for precipitating and removing the deposits contained in the water. [2]: The exhaust device according to [1] above, wherein the storage tank has a mortar-shaped bottom and is provided with a drain outlet at the very bottom. [3]: The exhaust system of [1] or [2], wherein the water supply device is connected to the storage tank and circulates and supplies supernatant water supplied from the storage tank to the exhaust pipe. [4]: The exhaust system according to [1], [2] or [3], wherein the water supply device supplies water to the exhaust pipe by mist injection. [5]: A silicon single crystal manufacturing apparatus comprising the silicon single crystal pulling apparatus and the exhaust apparatus of [1], [2], [3] or [4]. [6]: An exhaust method using an exhaust device connected to a silicon single crystal pulling apparatus that includes a chamber and a quartz crucible in the chamber and that pulls up a silicon single crystal from a raw material melt contained in the quartz crucible, the exhaust method using the exhaust device of [1], [2], [3] or [4] as the exhaust device, supplying water to the exhaust pipe to remove deposits that have accumulated in the exhaust pipe, storing the water drained from the exhaust pipe, and removing the deposits contained in the water by precipitating them. [7]: The exhaust method according to [6], further comprising circulating and supplying the supernatant of the stored water to the exhaust pipe. [8]: The exhaust method according to [6] above, which includes supplying the water by mist spraying. [9]: A method for producing a silicon single crystal, comprising producing a silicon single crystal using the silicon single crystal production apparatus according to [5] above.

[0070] The present invention is not limited to the above-described embodiments. The above-described embodiments are merely examples, and anything that has substantially the same configuration as the technical idea described in the claims of the present invention and that exhibits similar effects is included within the technical scope of the present invention. [Explanation of symbols]

[0071] 1...exhaust device, 2...raw material melt (silicon melt), 3...quartz crucible, 4...graphite crucible, 5...graphite heater, 6...chamber, 7...vacuum pump, 8...exhaust pipe, 9...exhaust gas collection pipe, 10...seed crystal, 11...silicon single crystal, 12...lower shaft, 20...storage tank, 21...water supply device, 22...supply water, 23...Circulation pump, 24...Water, 24A...Supernatant water, 25...Water drain valve, 30, 30A1, 30A2, 30An (n≧2)...silicon single crystal pulling apparatus, 31...Connection part, 40...Silicon single crystal manufacturing apparatus.

Claims

1. An exhaust device connected to a silicon single crystal pulling device that includes a chamber and a quartz crucible in the chamber, and that pulls a silicon single crystal from a raw material melt contained in the quartz crucible, The exhaust device comprises: an exhaust pipe connected to the chamber for exhausting the inert gas introduced into the chamber; a water supply device connected to the exhaust pipe and configured to supply water to the exhaust pipe for removing deposits accumulated in the exhaust pipe; and a storage tank connected to the exhaust pipe, which stores the water drained from the exhaust pipe and removes the sediments contained in the water by settling them.

2. 2. The exhaust system according to claim 1, wherein the storage tank has a bottom that is shaped like a mortar and is provided with a drain valve at the bottom.

3. 2. The exhaust system according to claim 1, wherein the water supply device is connected to the storage tank, and circulates and supplies supernatant water supplied from the storage tank to the exhaust pipe.

4. 3. The exhaust system according to claim 2, wherein the water supply device is connected to the storage tank, and circulates and supplies supernatant water supplied from the storage tank to the exhaust pipe.

5. 2. The exhaust system according to claim 1, wherein the water supply device supplies water to the exhaust pipe by spraying mist.

6. A silicon single crystal manufacturing apparatus comprising the silicon single crystal pulling apparatus and the exhaust system according to any one of claims 1 to 5.

7. An exhaust method using an exhaust device connected to a silicon single crystal pulling apparatus that includes a chamber and a quartz crucible in the chamber and pulls a silicon single crystal from a raw material melt contained in the quartz crucible, comprising: The exhaust method comprises: The exhaust device according to any one of claims 1 to 5 is used as the exhaust device, supplying water to the exhaust pipe to remove deposits accumulated in the exhaust pipe; An exhaust method comprising storing the water drained from the exhaust pipe and removing the sediments contained in the water by settling them out.

8. 8. The exhaust method according to claim 7, wherein the supernatant water of the stored water is circulated and supplied to the exhaust pipe.

9. 8. The exhaust method according to claim 7, wherein the water is supplied by mist spraying.

10. A method for producing a silicon single crystal, comprising producing a silicon single crystal using the silicon single crystal production apparatus according to claim 6.

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