Dust collection and cooling device and dust collection and cooling method for use in crucible or heater of single crystal pulling device

Abstract

To provide a dust collection cooling device capable of effectively collecting dust when cooling the crucible or heater of a single crystal pulling apparatus and effectively promoting the cooling.SOLUTION: A dust collection cooling device 100 includes a cover 10, a duct 20 and a dust collection suction machine 30. The cover 10 covers a crucible 116 or a heater 124 from above and the lower part is open; the duct 20 connects the cover 10 and the dust collection suction machine 30; the operation of the dust collection suction machine 30 pours an air flow into the internal space of the cover 10 from the lower part of the cover 10; and in the process of the air flow passing around the periphery of the heater 124 or the crucible 116 and flowing into the dust collection suction machine 30 through the inside of the duct 20, the dust collection suction machine 30 collects dust and the air flow promotes cooling.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a dust collection and cooling device and method for collecting dust generated from a crucible or heater in a single crystal pulling apparatus when the crucible or heater is cooled, and for accelerating cooling. [Background technology]

[0002] A typical method for manufacturing a single crystal silicon ingot is the Czochralski method (CZ method). In the CZ method, a silicon single crystal pulling apparatus 1000 installed in a clean room, as shown in FIG. 3, is used. During pulling of the single crystal, oxygen contained in the quartz crucible 116A reacts with the silicon melt to produce silicon oxide (SiO X ) is generated. This silicon oxide vaporizes and, as it moves along the flow of inert gas within the main chamber 110, cools and solidifies. It adheres to the inner wall surface of the main chamber 110 and the surfaces of various components (e.g., the heater 124) within the main chamber 110, gradually accumulating over time. Therefore, after the single crystal pulling is completed, the silicon single crystal pulling apparatus 1000 is disassembled and cleaned to remove this adhesion, i.e., disassembly and cleaning is performed. In this process, the main chamber 110 and the pull chamber 111 are separated, and the chamber space is opened to the clean room atmosphere (hereinafter, this is referred to as "opening the furnace"). Various components to be cleaned are then cleaned. In other words, the cleaning of the inner wall surface of the main chamber 110 and the various components (e.g., the heater 124) within the main chamber 110 is performed in the clean room atmosphere. Therefore, the removed adhesions become dust and float around the components to be cleaned within the clean room.

[0003] Patent Document 1 describes a dust removal device and method for preventing dust from scattering during dismantling and cleaning, thereby deteriorating the cleanliness of the clean room. In this device, the chamber is covered with a synthetic resin sheet, and an air intake fan and an intake hood are installed on either side of the chamber within the space covered by the synthetic resin sheet. The intake hood is connected to an exhaust fan installed in a pit below the floor of the clean room. A HEPA filter is installed immediately upstream of the exhaust fan. When the air intake fan and exhaust fan are operated, an airflow is generated from the air intake fan toward the chamber. The airflow is guided to the intake hood, where dust in the airflow is removed by the HEPA filter, and clean air is exhausted from the exhaust fan.

[0004] 3, when dismantling the silicon single crystal pulling apparatus 1000, in addition to cleaning the various components, various tasks are performed, such as removing residual silicon from the crucible 116 and replacing the crucible 116. Typically, when the pulling of an ingot is completed using the single crystal pulling apparatus 1000, the ingot is removed and then the furnace is opened. At this stage, the crucible 116 containing the residual silicon and the heater 124 positioned around it are at a high temperature of about 200°C. Therefore, the crucible 116 and the heater 124 are allowed to cool naturally until their temperatures have fallen to room temperature, for example, 50°C or less, before the various tasks described above are performed. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-224606 Summary of the Invention [Problem to be solved by the invention]

[0006] However, when the crucible 116 and the heater 124 are cooled naturally, it takes a long time to cool them, which causes a problem of extending the cycle time of the operation of the single crystal pulling apparatus. Also, since the crucible 116 and the heater 124 are at high temperatures immediately after opening the furnace, a strong upward air current occurs around the crucible 116 and the heater 124 due to thermal convection. Silicon oxide (SiO X In the crucible 116, due to the difference in thermal expansion coefficient between the remaining silicon and the quartz crucible 116A in contact with it, both the quartz and silicon begin to crack in minute areas, scattering fine powder of quartz and silicon. The scattering of these dust particles deteriorates the cleanliness of the clean room.

[0007] The technology of Patent Document 1 is for collecting dust that scatters during dismantling and cleaning, but is not for collecting dust that is generated from the crucible or heater when they are cooled. Patent Document 1 does not address the issue of dust that is generated from the crucible or heater when they are cooled, nor the long time it takes for them to cool before they can be dismantled.

[0008] In view of the above problems, the present invention aims to provide a dust collection and cooling device and a dust collection and cooling method that can effectively collect dust and effectively promote cooling when cooling a crucible or heater in a single crystal pulling apparatus. [Means for solving the problem]

[0009] The gist and configuration of the present invention are as follows. [1] A dust collection and cooling device that collects dust generated from a crucible or a heater located around the crucible in a single crystal pulling apparatus when the crucible or the heater is cooled after the ingot has been pulled by the single crystal pulling apparatus, and that promotes the cooling, a cover that covers the crucible or the heater from above and has an open bottom; A dust collector and a suction device a duct connecting the cover and the dust collecting suction device; When the dust collector / cooling device is activated, an airflow flows from below the cover into the internal space of the cover, and the airflow passes around the heater or the crucible and enters the dust collector / cooling device through the inside of the duct, during which the dust collector / cooling device collects the dust, and the airflow promotes the cooling.

[0010] [2] The dust collecting and cooling device according to [1] above, wherein one end of the duct is located inside the crucible.

[0011] [3] The dust collection and cooling device according to [1] or [2] above, wherein the dust collection suction machine is installed on the same floor as the single crystal pulling device.

[0012] [4] The dust collecting and cooling device according to any one of [1] to [3] above, wherein at least one selected from the cover, the duct, and the dust collecting suction machine has one or both of a heat insulator and a heat absorber.

[0013] [5] The dust collecting and cooling device according to any one of the above [1] to [4], wherein the dust collecting and suction machine has a heat exchanger for cooling the inside thereof.

[0014] [6] A dust collection and cooling method for collecting dust generated from a crucible or a heater located around the crucible in a single crystal pulling apparatus during cooling of the crucible or the heater located around the crucible in the single crystal pulling apparatus after the pulling of an ingot is completed by the single crystal pulling apparatus, and for accelerating the cooling, comprising: The crucible or the heater is covered with a cover from above, and the lower part of the cover is left open, Prepare a dust collector and suction device. The cover and the dust collecting suction device are connected by a duct, A dust collection and cooling method in which, by operating the dust collection suction machine, an airflow flows from below the cover into the internal space of the cover, and the airflow passes around the heater or around the crucible and flows into the dust collection suction machine through the inside of the duct, during which the dust collection suction machine collects the dust and the airflow promotes the cooling.

[0015] [7] The dust collection and cooling method according to [6] above, wherein one end of the duct is positioned inside the crucible.

[0016] [8] The dust collection and cooling method according to [6] or [7] above, wherein the dust collection suction machine is installed on the same floor as the single crystal pulling apparatus.

[0017] [9] The dust collection and cooling method according to any one of [6] to [8] above, wherein at least one selected from the cover, the duct, and the dust collection suction machine has one or both of a heat insulator and a heat absorber.

[0018]

[10] The dust collection and cooling method according to any one of the above [6] to [9], wherein the dust collection suction machine has a heat exchanger for cooling the inside thereof. [Effects of the Invention]

[0019] According to the dust collection and cooling device and method of the present invention, it is possible to effectively collect dust and effectively promote cooling when cooling the crucible or heater in a single crystal pulling apparatus. [Brief explanation of the drawings]

[0020] [Figure 1] 1 is a schematic diagram illustrating a dust collecting and cooling device 100 according to an embodiment of the present invention. [Figure 2] FIG. 2 is a schematic diagram showing a dust collecting and cooling device 200 according to another embodiment of the present invention. [Figure 3] 1 is a cross-sectional view taken along a pulling axis X, schematically showing the configuration of a silicon single crystal pulling apparatus 1000. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0021] (single crystal pulling equipment) First, with reference to FIG. 3, the configuration of a silicon single crystal pulling apparatus 1000, which is an example of a single crystal pulling apparatus to which one embodiment of the present invention is applied, will be described.

[0022] The silicon single crystal pulling apparatus 1000 includes a main chamber 110, a pull chamber 111, a crucible 116, a shaft 118, a shaft drive mechanism 120, a cylindrical heat shield 122, a cylindrical heater 124, a cylindrical heat insulator 126, a seed chuck 128, a pulling wire 130, a wire lifting mechanism 132, and a pair of electromagnets 134.

[0023] The main chamber 110 is a cylindrical chamber with a bottom that accommodates a crucible 116. The pull chamber 111 is a cylindrical chamber that has the same central axis as the main chamber 110, is provided above the main chamber 110, and has a smaller diameter than the main chamber 110. A gate valve 112 is provided between the main chamber 110 and the pull chamber 111, and the spaces within the main chamber 110 and the pull chamber 111 are connected to or disconnected from each other by opening and closing this gate valve 112. A gas inlet 113 is provided at the top of the pull chamber 111, through which an inert gas such as Ar gas is introduced into the main chamber 110. A gas outlet 114 is provided at the bottom of the main chamber 110, through which gas within the main chamber 110 is sucked in and discharged by driving a vacuum pump (not shown).

[0024] The crucible 116 is disposed in the center of the main chamber 110 and contains the silicon melt M. The crucible 116 has a double structure consisting of a quartz crucible 116A and a graphite crucible 116B. The quartz crucible 116A directly supports the silicon melt M on its inner surface. The graphite crucible 116B supports the quartz crucible 116A on the outside thereof.

[0025] The shaft 118 passes vertically through the bottom of the main chamber 110 and supports the crucible 116 at its upper end. The shaft driving mechanism 120 rotates and raises and lowers the crucible 116 via the shaft 118.

[0026] The thermal shield 122 is provided above the crucible 116 so as to surround the single crystal silicon ingot I pulled from the silicon melt M.

[0027] The cylindrical heater 124 is positioned within the main chamber 110 so as to surround the crucible 116. The heater 124 is generally a resistance heating heater made of carbon, and melts the silicon raw material introduced into the crucible 116 to form a silicon melt M, and further provides heating to maintain the formed silicon melt M.

[0028] The cylindrical heat insulator 126 is provided below the upper end of the heat shield 122 and spaced apart from the outer peripheral surface of the heater 124, along the inner surface of the main chamber 110. The heat insulator 126 has the function of imparting a heat retention effect to the area inside the main chamber 110, particularly below the heat shield 122, and making it easier to maintain the silicon melt M in the crucible 116.

[0029] Above the crucible 116, a pulling wire 130 that holds a seed chuck 128 that holds a seed crystal S at its lower end is arranged coaxially with the shaft 118, and a wire lifting mechanism 132 raises and lowers the pulling wire 130 while rotating it at a predetermined speed in the opposite direction to or the same direction as the shaft 118.

[0030] The pair of electromagnets 134 are positioned outside the main chamber 110, in a height range that encompasses the crucible 116, symmetrically with respect to the pulling axis X. By passing a current through the coils of the pair of electromagnets 34, a horizontal magnetic field that forms a horizontal magnetic field distribution with respect to the silicon melt M can be generated. Although FIG. 3 shows a pair of electromagnets 34 that generate a horizontal magnetic field, electromagnets that generate a cusp magnetic field that forms a cusp-shaped magnetic field distribution with respect to the silicon melt M may be disposed instead. If no magnetic field is applied to the silicon melt M during crystal growth, the electromagnets are not necessary.

[0031] As described above, once the pulling of an ingot is completed in the single crystal pulling apparatus 1000, the ingot is removed and then the furnace is opened. Referring also to FIGS. 1 and 2 , at this stage, the crucible 116 containing residual silicon R and the heater 124 located around it are at a high temperature of approximately 200°C. Conventionally, the crucible 116 and the heater 124 are naturally cooled until their temperatures drop to room temperature, e.g., 50°C or below. After this, various tasks are performed, such as cleaning the various components, removing the residual silicon from the crucible 116, or replacing the crucible 116. The dust collection and cooling device and dust collection and cooling method according to one embodiment of the present invention are applied when cooling the crucible 116 or the heater 124, preferably when cooling the crucible 116 and the heater 124.

[0032] (Dust collection and cooling device and dust collection and cooling method) A dust collecting and cooling device 100 and a dust collecting and cooling method according to one embodiment of the present invention will be described with reference to Figure 1. The dust collecting and cooling device 100 and the dust collecting and suction method using the same are intended to collect dust generated from one or both of the crucible 116 and the heater 124 in a single crystal pulling apparatus when one or both of the crucible 116 and the heater 124 are cooled after the single crystal pulling apparatus has completed pulling an ingot, and to promote cooling of one or both of the crucible 116 and the heater 124. The dust collecting and cooling device 100 has a cover 10, a duct 20, and a dust collecting and suction device 30 as its main components.

[0033] [cover] The cover 10 covers one or both of the crucible 116 and the heater 124 (preferably both) from above, leaving the bottom open. That is, there is a gap between the bottom end of the cover 10 and the chamber base 136. This embodiment focuses on one or both of the crucible 116 and the heater 124 in particular, and focuses on dust generated from them during cooling, among other things, within the single crystal pulling apparatus. Therefore, the cover 10 covers one or both of the crucible 116 and the heater 124 when the main chamber 110 is not covered after the furnace is opened. Note that the chamber base 136 shown in FIG. 1 is the top surface of the division opening when the chamber 110 is divided at the bottom of the chamber 110 in FIG. 3, and the height position of the chamber base 136 is at floor level, i.e., the same height as the floor of the clean room.

[0034] The material of the cover 10 is not particularly limited. However, it is preferable that the cover 10 cover one or both of the crucible 116 and the heater 124 from above without contacting either or both of them, and it is preferable that the cover 10 have the necessary rigidity for this purpose. Furthermore, it is preferable that the cover 10 have heat resistance capable of withstanding the radiant heat from the high-temperature crucible 116 and heater 124. As an example, the cover 10 has a three-layer structure consisting of an interior 10A, an insulator 10B, and an exterior 10C. The interior 10A can be a lined stainless steel plate. By lining the stainless steel plate of the interior 10A, it is possible to prevent the stainless steel plate from directly contacting the heater 124 and causing stainless steel chips to adhere to the heater 124. The lining material is preferably Teflon (registered trademark) resin or carbon. The exterior 10C can be a stainless steel plate. By disposing the insulator 10B between the interior 10A and the exterior 10C, it is possible to suppress the temperature rise outside the cover 10. Since the heat insulator 10B can be a dust source, it is preferable to sandwich it between the inner casing 10A and the outer casing 10C. It is also preferable that the cover 10 has a vacuum double structure, which makes the heat insulator 10B unnecessary.

[0035] The shape and dimensions of the cover 10 are not limited as long as it can cover one or both of the crucible 116 and the heater 124 from above. However, from the viewpoint of minimizing the size of the space within the cover 10 that covers the crucible 116 and the heater 124, as shown in FIG. 1, the cover 10 preferably has a flat, horizontally extending top portion, vertically extending sides connected to the top portion, and no bottom portion. The shape of the top portion is preferably circular, similar to the shape of the crucible 116 and the heater 124. This facilitates uniform airflow within the cover 10. The interior dimensions of the cover 10 preferably have an inner diameter of approximately 500 to 2500 mm and a height of approximately 300 to 1500 mm. When the cover 10 is in use, the inner diameter of the cover 10 is preferably 100 to 300 mm larger than the outer diameter of the heater 124, and the gap between the inner surface of the top of the cover 10 and the upper end of the heater 124 is preferably 100 to 300 mm. Furthermore, the gap between the lower end of the cover 10 and the chamber base 136 is preferably 50 to 150 mm.

[0036] [duct] The duct 20 connects the cover 10 to the dust collector suction device. Specifically, the cover 20 is inserted from the top of the cover 10 so that one end is located in the interior space of the cover 10, and the other end is connected to the dust collector suction device 30. From the viewpoints of dust collection efficiency and cooling promotion efficiency, it is preferable that one end of the duct 20 is located inside the crucible 116. The material of the duct 20 is not particularly limited, but it is preferable that it has heat resistance that can withstand the high-temperature airflow passing through it. As an example, the duct 20 has a three-layer structure consisting of a duct body 20A, a heat insulator 20B, and an exterior casing 20C. The duct body 20A can be made of Teflon (registered trademark) or a stainless steel plate and is inserted from the top of the cover 10, with one end located in the interior space of the cover 10, preferably inside the crucible 116. The exterior casing 20C can be made of a stainless steel plate. By disposing the heat insulator 20B between the duct body 20A and the exterior casing 20C, it is possible to suppress a rise in temperature outside the duct 20. Since the heat insulator 20B can also be a source of dust, it is preferable to sandwich it between the duct body 20A and the exterior casing 20C. It is also preferable that the duct 20 has a vacuum double structure. This makes the heat insulator 20B unnecessary.

[0037] The shape and dimensions of the duct 20 are not particularly limited. Regarding the shape, for example, the cross section perpendicular to the extension direction may be circular or rectangular. If the duct 20 is circular, the inner diameter of the duct 20 may be about 40 to 600 mm, and if the duct 20 is rectangular, the inner dimension of each side may be about 40 to 600 mm. The length of the duct 20 is also not particularly limited as long as the other end can be connected to the dust collecting suction machine 30.

[0038] [Dust collection suction machine] The structure of the dust collecting and suction machine 30 will be described with reference to FIG. 1. The dust collector 30 has a housing 34 and a suction blower 35 located therein. Two stages of filters (a medium-efficiency filter 31 and a HEPA filter 32) are installed upstream of the airflow generated by the suction blower 35. The interior of the dust collecting and suction machine 30 (the interior of the housing 34) is partitioned by the medium-efficiency filter 31 and the HEPA filter 32 into a first internal space 33A, a second internal space 33B, and a third internal space 33C, from the upstream side of the airflow. In this embodiment, the suction blower 35 is disposed in the second internal space 33B, but this is not limiting and any space may be located inside the housing 34. The suction blower 35 preferably has heat resistance capable of withstanding the high-temperature airflow flowing into the dust collecting and suction machine 30.

[0039] The other end of duct 20 is connected to a portion of housing 34 that defines first internal space 33A. Therefore, the airflow passing through duct 20 first flows into first internal space 33A of dust collector / suction unit 30. The airflow that flows into first internal space 33A passes through medium-efficiency filter 31 on its way to second internal space 33B. Medium-efficiency filter 31 has the function of capturing dust particles with a particle size of approximately 1 μm or more. The airflow that flows into second internal space 33B passes through HEPA filter 32 on its way to third internal space 33C. HEPA filter 32 has the function of capturing dust particles with a particle size of approximately 0.3 μm or more. The airflow that flows into third internal space 33C is discharged to the outside of dust collector / suction unit 30 via exhaust port 36, which is provided in the portion of housing 34 that defines third internal space 33C. That is, the dust collector suction machine 30 sucks in air containing dust from inside the duct 20, captures the dust with the medium-performance filter 31 and the HEPA filter 32, and releases clean air that does not contain dust with a particle size of 0.3 μm or more.

[0040] As an example, the housing 34 has a three-layer structure consisting of an interior casing 34A, a heat insulator 34B, and an exterior casing 34C. The interior casing 34A can be made of stainless steel plate. However, as shown in FIG. 1, the interior casing 34A may be provided only in the portion of the housing 34 that defines the third internal space 33C downstream of the HEPA filter 32. Because the heat insulator 34B can be a dust source, it is preferable to sandwich it between the interior casing 34A and the exterior casing 34C downstream of the HEPA filter 32. However, even if the heat insulator 34B is exposed upstream of the HEPA filter 32, dust generated by the heat insulator 34B can be captured by the HEPA filter 32. The provision of the heat insulator 34B can suppress temperature rise outside the dust collector / suction device 30. The exterior casing 34C can be made of stainless steel plate. The housing 34 also preferably has a double vacuum structure. This eliminates the need for the heat insulator 34B.

[0041] When the dust collector suction device 30 is activated, that is, when the suction blower 35 is activated, an airflow is generated as follows. First, an airflow flows from below the cover 10 into the internal space of the cover 10, passes around the heater 124 and / or the crucible 116, and enters the dust collector suction device 30 through the inside of the duct 20. This airflow contains dust generated from one or both of the heater 124 and the crucible 116, and the dust collector suction device 30 can collect the dust, preventing it from scattering inside the clean room in which the silicon single crystal pulling apparatus 1000 is installed. This is because the bottom of the cover 10 is open and the duct 20 is inserted from the top of the cover 10 so that one end is positioned within the internal space of the cover 10. As a result, in this embodiment, even without an air supply means such as an air supply fan, by simply operating the suction blower 35 of the dust collector / suction device 30, an air current can be formed to effectively collect dust generated from one or both of the heater 124 and the crucible 116. Furthermore, this air current can effectively remove heat from one or both of the heater 124 and the crucible 116, thereby effectively promoting the cooling of one or both of the heater 124 and the crucible 116.

[0042] If the dust suction device 30 is installed in a pit below the floor of the clean room, the pressure in the clean room may drop, which may cause a deterioration in the cleanliness of the clean room. Therefore, it is preferable that the dust suction device 30 is installed on the same floor as the single crystal pulling apparatus 1000 (i.e., in the clean room). This eliminates the concern that the pressure in the clean room may drop, causing a deterioration in the cleanliness of the clean room.

[0043] For example, the dust collector / suction device 30 is installed on a cart 50 with an elevator mechanism that is installed on the floor in a clean room. When the dust collector / suction device 30, the duct 20, and the cover 10 are fixed together, the cover 10 can be raised and lowered to cover the crucible 116 and the heater 124 by raising and lowering the cart 50 with an elevator mechanism.

[0044] [Modification of dust collection suction machine] A dust collecting and cooling device 200 and a dust collecting and cooling method according to another embodiment of the present invention will be described with reference to Fig. 2. The dust collecting and cooling device 200 and the dust collecting and suction method using the same are the same as the dust collecting and cooling device 100 shown in Fig. 1, except that the configuration of the dust collecting and suction device 40 is different from that of the dust collecting and suction device 30. Therefore, the description of Fig. 1 is used to describe the cover 10 and the duct 20.

[0045] The structure of the dust collecting suction machine 40 will be described with reference to FIG. 2. The dust collecting machine 40 has a housing 44 and a suction blower 45 located therein. Two filters (a medium-efficiency filter 41 and a HEPA filter 42) are installed upstream of the airflow generated by the suction blower 45. The interior of the dust collecting suction machine 40 (the interior of the housing 44) is divided into a first internal space 43A, a second internal space 43B, and a third internal space 43C, from the upstream side of the airflow, by the medium-efficiency filter 41 and the HEPA filter 42. In this embodiment, the suction blower 45 is located in the second internal space 43B, but is not limited thereto and may be located anywhere inside the dust collecting suction machine 40. The suction blower 45 preferably has heat resistance capable of withstanding the high-temperature airflow flowing into the dust collecting suction machine 40.

[0046] The other end of duct 20 is connected to a portion of housing 44 that defines first internal space 43A. Therefore, the airflow passing through duct 20 first flows into first internal space 43A of dust collector / suction unit 40. The airflow that flows into first internal space 43A passes through medium-efficiency filter 41 on its way to second internal space 43B. Medium-efficiency filter 41 has the function of capturing dust particles with a particle size of approximately 1 μm or larger. The airflow that flows into second internal space 43B passes through HEPA filter 42 on its way to third internal space 43C. HEPA filter 42 has the function of capturing dust particles with a particle size of approximately 0.3 μm or larger. Third internal space 43C is defined by housing 44 and a stainless steel punched plate 46. The airflow that flows into third internal space 43C is discharged to the outside of dust collector / suction unit 40 through the through-holes in punched plate 46. That is, the dust collector suction machine 40 sucks in air containing dust from inside the duct 20, captures the dust with the medium-performance filter 41 and the HEPA filter 42, and releases clean air that does not contain dust with a particle size of 0.3 μm or more.

[0047] As an example, the housing 44 has a three-layer structure consisting of an interior 44A, a heat insulator 44B, and an exterior 44C. The interior 44A can be made of stainless steel plate. However, as shown in FIG. 2, the interior 44A may be provided only in a portion of the housing 44 that defines the third internal space 43C downstream of the HEPA filter 42. By providing the heat insulator 44B, it is possible to suppress a rise in temperature outside the dust collector / suction device 40. The exterior 44C can be made of stainless steel plate. It is also preferable that the housing 44 has a double vacuum structure. This eliminates the need for the heat insulator 44B.

[0048] The description of FIG. 1 is used to explain the airflow generated by the operation of the dust collector / suction device 40 and the resulting dust collection and cooling promotion. Furthermore, in this embodiment, the dust collector / suction device 40 has a heat exchanger 47 and a cooler 48. The heat exchanger 47 is disposed in the third internal space 43C, but is not limited to this, and may be disposed inside the housing 44. The cooler 48 is disposed outside the housing 44, but is not limited to this, and may be connected to the heat exchanger 47. In this embodiment, the high-temperature airflow that has flowed into the housing 44 is cooled by the heat exchanger 47 connected to the cooler 48. As a result, heat can be more effectively removed from one or both of the heater 124 and the crucible 116, thereby more effectively promoting cooling of one or both of the heater 124 and the crucible 116.

[0049] As in FIG. 1, it is preferable that the dust collector suction machine 40 is installed on the same floor as the single crystal pulling apparatus 1000 (i.e., in a clean room), for example, on a cart 50 with an elevator mechanism installed on the floor of the clean room.

[0050] [Insulators and absorbers] The materials for the insulators 10B, 20B, 34B, and 44B are not particularly limited, but may be, for example, Teflon (registered trademark) sponge or surface-coated carbon. At least one of the insulators 10B, 20B, 34B, and 44B may be replaced with a heat absorber. Alternatively, a heat absorber may be provided in addition to the insulators 10B, 20B, 34B, and 44B in at least one selected from the cover 10, the duct 20, the dust collector suction device 30, and the dust collector suction device 40. The provision of a heat absorber allows for more effective heat removal from one or both of the heater 124 and the crucible 116, thereby more effectively promoting cooling of one or both of the heater 124 and the crucible 116. The material for the heat absorber is not particularly limited, but may be, for example, ceramic fiber or porous PTFE material. [Example]

[0051] (Example of invention) A dust collecting and cooling apparatus 100 shown in Fig. 1 was prepared. After completing the pulling of an ingot using a silicon single crystal pulling apparatus and removing the ingot, the furnace was opened. The crucible and heater immediately after opening the furnace were cooled using the dust collecting and cooling apparatus 100 shown in Fig. 1 by the dust collecting and cooling method described with reference to Fig. 1 until the crucible and heater reached 50°C or below.

[0052] (Comparative Example) After the ingot was completely pulled using the silicon single crystal pulling apparatus and removed, the furnace was opened. Immediately after opening the furnace, the crucible and heater were allowed to cool naturally until they reached 50°C or lower.

[0053] [evaluation] When comparing the time it took for the crucible and heater to drop below 50°C immediately after opening the furnace, it was 90 minutes in the comparative example, while it was 25 minutes in the inventive example, indicating that cooling was effective in the inventive example.

[0054] In addition, for both the invention example and the comparative example, the number of particles (maximum value) in the clean room during cooling was measured. Specifically, the number of particles was measured at one-minute intervals at the position of the cover opening during cooling, and the maximum value among the measured values ​​was adopted. As a result, the number of particles with a diameter of 0.3 μm or more was 5,000 particles / ft in the comparative example. 3 In the invention example, the number was 10 pieces / ft 3 It can be seen that the dust was effectively collected in the example of the present invention. [Industrial Applicability]

[0055] According to the dust collection and cooling device and method of the present invention, it is possible to effectively collect dust and effectively promote cooling when cooling the crucible or heater in a single crystal pulling apparatus. [Explanation of symbols]

[0056] 100 Dust collection cooling device 200 Dust collection cooling device 10 Cover 10A Interior (stainless steel + lining) 10B Insulator 10C Exterior (stainless steel) 20 Duct 20A duct body 20B Insulator 20C exterior (stainless steel) 30 Dust collector suction machine 31 Medium-performance filter 32 HEPA filters 33A 1st internal space 33B 2nd internal space 33C 3rd internal space 34 Case 34A Interior (stainless steel) 34B Insulator 34C exterior (stainless steel) 35 Suction Blower 36 Exhaust port 40 Dust collector suction machine 41 Medium-performance filter 42 HEPA filters 43A 1st internal space 43B 2nd internal space 43C 3rd internal space 44 Case 44A Interior (stainless steel) 44B Insulator 44C exterior (stainless steel) 45 Suction Blower 46 Punching plate (stainless steel) 47 Heat exchanger 48 Cooler 50 Lifting mechanism trolley 1000 Silicon single crystal pulling equipment 110 Main Chamber 111 Pull Chamber 112 Gate valve 113 Gas inlet 114 Gas outlet 116 Crucible 116A Quartz Crucible 116B graphite crucible 118 Shaft 120 Shaft drive mechanism 122 Heat Shield 124 Heater 126 Insulator 128 Seed Chuck 130 Pulling wire 132 Wire lifting mechanism 134 Electromagnet 136 Chamber Base S seed crystal M Silicon melt I. Single crystal silicon ingot X lifting shaft R Residual silicon

Claims

1. A dust collection and cooling device that collects dust generated from a crucible or a heater located around the crucible in a single crystal pulling apparatus when the crucible or the heater is cooled after the ingot has been pulled by the single crystal pulling apparatus, and that promotes the cooling, a cover that covers the crucible or the heater from above and has an open bottom; A dust collector and a suction device a duct connecting the cover and the dust collecting suction device; a gap is provided between the lower end of the cover and the chamber base of the single crystal pulling apparatus, and when the dust collector / suction device is activated, an airflow flows into the internal space of the cover from the gap between the lower end of the cover and the chamber base, and the airflow passes around the heater or the crucible and enters the dust collector / suction device through the inside of the duct, during which the dust collector / suction device collects the dust, and the airflow promotes the cooling.

2. The dust collecting and cooling device according to claim 1 , wherein one end of the duct is located inside the crucible.

3. 3. The dust collection and cooling device according to claim 1, wherein the dust collection suction machine is installed in the same clean room as the single crystal pulling device.

4. The dust collecting and cooling device according to claim 1 or 2, wherein at least one selected from the cover, the duct, and the dust collecting suction machine has one or both of a heat insulator and a heat absorber.

5. The dust collecting and cooling device according to claim 1 or 2, wherein the dust collecting and suction machine has a heat exchanger for cooling the inside thereof.

6. A dust collection and cooling method for collecting dust generated from a crucible or a heater located around the crucible in a single crystal pulling apparatus during cooling of the crucible or the heater located around the crucible in the single crystal pulling apparatus after completing pulling of an ingot using the single crystal pulling apparatus, and for accelerating the cooling, comprising: the crucible or the heater is covered with a cover from above, the lower end of the cover is left open, and a gap is provided between the lower end of the cover and a chamber base of the single crystal pulling apparatus; Prepare a dust collector and suction device. The cover and the dust collecting suction device are connected by a duct, A dust collection and cooling method in which, by operating the dust collector and suction machine, an airflow flows into the internal space of the cover from the gap between the lower end of the cover and the chamber base, and the airflow passes around the heater or around the crucible and flows into the dust collector and suction machine through the inside of the duct, in which the dust collector and suction machine collects the dust and the airflow promotes the cooling.

7. The dust collecting and cooling method according to claim 6, wherein one end of the duct is positioned inside the crucible.

8. 8. The dust collection and cooling method according to claim 6, wherein the dust collection suction machine is installed in the same clean room as the single crystal pulling apparatus.

9. The dust collection and cooling method according to claim 6 or 7, wherein at least one selected from the cover, the duct, and the dust collection suction machine has one or both of a heat insulator and a heat absorber.

10. 8. The dust collection and cooling method according to claim 6, wherein the dust collection suction machine has a heat exchanger for cooling the inside thereof.

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