Tail gas treatment device for preparing antimony-doped monocrystalline silicon and monocrystalline silicon preparation system

Abstract

The embodiment of the invention relates to the field of monocrystalline silicon production, and provides a tail gas treatment device for preparing antimony-doped monocrystalline silicon and a monocrystalline silicon preparation system.The tail gas treatment device comprises an equipment shell, a heater, a reducer and a collector, the equipment shell is provided with a tail gas inlet, and the tail gas inlet is used for being communicated with an exhaust port of a single crystal furnace; antimony-containing tail gas discharged from the single crystal furnace enters the equipment shell; the heater is arranged on the equipment shell and is used for heating antimony-containing tail gas entering the equipment shell; the reducer is arranged in the equipment shell and is used for carrying out reduction reaction with antimony trioxide in the antimony-containing tail gas in the equipment shell to generate an antimony simple substance; the collector is detachably arranged on the equipment shell and used for collecting the antimony simple substance falling from the reducer. According to the tail gas treatment device for preparing the antimony-doped monocrystalline silicon and the preparation system of the monocrystalline silicon provided by the embodiment of the invention, antimony trioxide in the tail gas generated during preparation of the antimony-doped monocrystalline silicon can be prevented from harming a human body.

Description

Technical Field

[0001] The embodiments of the present disclosure relate to the field of single crystal silicon production, and in particular to an exhaust gas treatment device for preparing antimony-doped single crystal silicon and a single crystal silicon preparation system. Background Art

[0002] Since N-type monocrystalline silicon is more efficient than P-type monocrystalline silicon, phosphorus dopants are widely used in the photovoltaic industry to make the electrical properties of silicon wafers show N-type. As competition in the photovoltaic industry becomes increasingly fierce, the research and application of new doping elements are urgent. The performance of monocrystalline silicon cells and related research of related dopants such as arsenic, antimony, bismuth, selenium, and tellurium have also attracted much attention in academia and industry. At present, the tail gas generated when preparing antimony-doped monocrystalline silicon is still recovered by the tail gas recovery method of preparing phosphorus-doped monocrystalline silicon. Due to the characteristics of antimony with extremely small segregation coefficient and extremely large evaporation coefficient, antimony will easily produce the oxide antimony trioxide when it comes into contact with oxygen. Antimony trioxide has certain toxicity and potential health risks. Summary of the invention

[0003] The embodiments of the present disclosure provide an exhaust gas treatment device for preparing antimony-doped single crystal silicon and a single crystal silicon preparation system, which are intended to prevent antimony trioxide in the exhaust gas generated when preparing antimony-doped single crystal silicon from harming the human body.

[0004] According to some embodiments of the present disclosure, on one hand, an exhaust gas treatment device for preparing antimony-doped single crystal silicon is provided, comprising:

[0005] An equipment housing, wherein the equipment housing is provided with an exhaust gas inlet, and the exhaust gas inlet is used to communicate with the exhaust port of the single crystal furnace so as to allow the antimony-containing exhaust gas discharged from the single crystal furnace to enter the equipment housing;

[0006] A heater, the heater being disposed on the device housing and used for heating the antimony-containing tail gas entering the device housing;

[0007] A reducer, the reducer is arranged in the device housing, and the reducer is used to generate antimony element by a reduction reaction with antimony trioxide in the antimony-containing tail gas in the device housing;

[0008] A collector, wherein the collector is detachably mounted on the device housing, the collector is located at the lower side of the reducer, and the collector is used to collect the antimony element falling from the reducer.

[0009] In some embodiments, the exhaust gas treatment device for preparing antimony-doped single crystal silicon also includes a cooler, which is arranged on the equipment housing or the collector corresponding to the reducer, and is used to cool the generated antimony element and the unreacted gas in the equipment housing.

[0010] In some embodiments, the cooler is disposed at the bottom of the collector.

[0011] In some embodiments, a collecting port is provided on the device housing, the collecting port is located at the lower side of the reducer, the collector is located outside the device housing, and the collector is detachably provided at the collecting port.

[0012] In some embodiments, an exhaust gas outlet is provided on the device housing, two heaters are provided at the exhaust gas inlet and the exhaust gas outlet respectively, and the reducer is located between the two heaters.

[0013] In some embodiments, the heater is disposed in the device housing, a heating power interface module is disposed on the outer shell wall of the device housing, and the heating power interface module is electrically connected to the heater.

[0014] In some embodiments, the heater is configured in a cylindrical shape that matches the shape of the device housing.

[0015] In some embodiments, the reducer includes a support frame and a graphite carbon rod. Two support frames are provided. The two support frames are spaced apart from each other in the flow direction of the gas in the device housing. A plurality of graphite carbon rods extending along the flow direction of the gas in the device housing are provided between the two support frames.

[0016] In some embodiments, the exhaust gas treatment device for preparing antimony-doped single crystal silicon also includes a filter tank, the inlet and outlet of the filter tank are respectively connected to the exhaust port of the single crystal furnace and the exhaust gas inlet, so that the antimony-containing exhaust gas discharged from the single crystal furnace can enter the equipment housing after passing through the filter tank.

[0017] According to some embodiments of the present disclosure, another aspect of the present disclosure further provides a system for preparing single crystal silicon, including:

[0018] A single crystal furnace, wherein the single crystal furnace is used to prepare antimony-doped single crystal silicon;

[0019] An exhaust gas treatment device for preparing antimony-doped single crystal silicon, wherein the exhaust gas treatment device for preparing antimony-doped single crystal silicon is an exhaust gas treatment device for preparing antimony-doped single crystal silicon as described in any one of the above embodiments, and the exhaust gas inlet of the exhaust gas treatment device for preparing antimony-doped single crystal silicon is connected to the exhaust port of the single crystal furnace;

[0020] A gas treatment device, wherein the gas inlet of the gas treatment device is connected to the tail gas outlet of the tail gas treatment device for preparing antimony-doped single crystal silicon, and the gas treatment device is used to treat the gas discharged from the tail gas treatment device for preparing antimony-doped single crystal silicon.

[0021] In some embodiments, the single crystal silicon preparation system further includes a regulating valve, wherein the first end and the second end of the regulating valve are respectively connected to the exhaust port of the single crystal furnace and the tail gas inlet of the tail gas treatment device for preparing antimony-doped single crystal silicon, so that the tail gas inlet of the tail gas treatment device for preparing antimony-doped single crystal silicon is connected to the exhaust port of the single crystal furnace through the regulating valve, and the third end of the regulating valve is connected to the gas inlet of the gas treatment device;

[0022] Among them, when the single crystal silicon preparation system is in a first exhaust state, the first end of the regulating valve is connected to the second end, and the first end of the regulating valve is disconnected from the third end; when the single crystal silicon preparation system is in a second exhaust state, the first end of the regulating valve is disconnected from the second end, and the first end of the regulating valve is connected to the third end.

[0023] The technical solution provided by the embodiments of the present disclosure has at least the following advantages:

[0024] In the exhaust gas treatment device for preparing antimony-doped single crystal silicon provided in the embodiment of the present disclosure, the antimony-containing exhaust gas generated by the single crystal furnace when preparing antimony-doped single crystal silicon can enter the equipment shell, and the antimony-containing exhaust gas entering the equipment shell is mixed with the reducer. The heater can heat the antimony-containing exhaust gas entering the equipment shell, so that antimony trioxide in the antimony-containing exhaust gas reacts with the reducer at high temperature to generate antimony element, and the antimony element can fall freely under the action of gravity and enter the collector to prevent the antimony element from undergoing secondary reaction. The antimony element collected in the collector can be recycled, which can not only prevent the antimony trioxide in the exhaust gas generated when preparing antimony-doped single crystal silicon from harming the human body, but also reduce the consumption of antimony dopants in the process of preparing antimony-doped single crystal silicon. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] One or more embodiments are exemplarily illustrated by pictures in the corresponding drawings, and these exemplified descriptions do not constitute a limitation on the embodiments. Unless otherwise specified, the pictures in the drawings do not constitute a scale limitation. In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the traditional technology, the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0026] Figure 1 A schematic structural diagram of a tail gas treatment device for preparing antimony-doped single crystal silicon provided in one embodiment of the present disclosure;

[0027] Figure 2 for Figure 1 A cross-sectional view of a tail gas treatment device for preparing antimony-doped single crystal silicon;

[0028] Figure 3 for Figure 2 Schematic diagram of the structure of the reducer;

[0029] Figure 4 A schematic diagram of the structure of a single crystal silicon preparation system provided in one embodiment of the present disclosure. DETAILED DESCRIPTION

[0030] As can be seen from the background technology, due to the extremely small evaporation coefficient of phosphorus, most of the phosphorus dopants will enter the solid-liquid interface with the segregation effect, and will be distributed as evenly as possible in the radial direction. In the axial direction, with the reduction of the amount of melt, the enrichment of impurities, and the reduction of dopants, the resistance of the single crystal silicon rod will have a tailing effect, that is, a state of high head and low tail. In the preparation process of N-type single crystal silicon, while adding phosphorus dopants, the remaining five groups of dopants such as antimony are doped in, which can effectively solve the resistivity tailing effect of single crystal silicon and improve the slice utilization rate of a single single crystal silicon rod. For example, when phosphorus is doped alone, a 5-meter-long single crystal silicon rod can only be sliced ​​for the battery process due to the tailing effect of resistivity, and the last two meters can be directly scrapped because of the low resistivity and cannot meet the battery efficiency requirements. However, after antimony is doped in at the same time, the tailing resistance effect of the single crystal silicon rod will be effectively alleviated, and the entire resistance axial distribution can be effectively flattened. 4.8 meters of the 5-meter single crystal silicon rod can be used, so antimony doping can bring significant cost advantages.

[0031] The environment of CZ-pulled single crystal silicon is close to vacuum state, and is protected by inert gas such as argon, although it is oxygen-free in theory. However, the melting of silicon dioxide in the quartz crucible of the single crystal furnace will produce oxygen vapor, and the single crystal furnace is not completely sealed. There is an equipment leakage rate indicator, and oxygen in the air will enter the single crystal furnace. Due to the high evaporation property of antimony, antimony will easily produce antimony trioxide oxide when it comes into contact with oxygen. Antimony trioxide has certain toxicity and potential health risks, so the tail gas generated when preparing antimony-doped single crystal silicon will contain antimony trioxide.

[0032] At present, the tail gas generated when preparing antimony-doped single crystal silicon is still recovered by the tail gas recovery method of preparing phosphorus-doped single crystal silicon, that is, the inert gas is input from the lifting head of the single crystal furnace and discharged from the gas guide hood at the bottom of the single crystal furnace. The tail gas discharged from the single crystal furnace is filtered out of various slags by the filter tank under the suction of the power pump, and the remaining gas will re-enter the gas station (i.e., the inert gas recovery system) for recovery and treatment. Although antimony trioxide in the tail gas mainly exists as gas, a small amount of antimony trioxide will still be mixed in the filter tank. In this way, during the manual regular cleaning of the filter tank, the antimony trioxide mixed in the filter tank will have serious adverse effects on the human body and the surrounding environment, and the antimony trioxide recovered by the inert gas recovery system will have adverse effects on the entire inert gas recovery system.

[0033] The present disclosure provides an exhaust gas treatment device for preparing antimony-doped single crystal silicon and a single crystal silicon preparation system. A reducer is arranged in the equipment shell of the exhaust gas treatment device for preparing antimony-doped single crystal silicon, so that a reduction reaction zone is formed in the equipment shell. The antimony-containing exhaust gas generated by the single crystal furnace when preparing antimony-doped single crystal silicon can enter the equipment shell from the exhaust gas inlet. The antimony-containing exhaust gas entering the equipment shell can flow to the reduction reaction zone and mix with the reducer. At the same time, the antimony-containing exhaust gas entering the equipment shell is heated by a heater, so that antimony trioxide in the antimony-containing exhaust gas undergoes a reduction reaction with the reducer at high temperature to generate antimony element, thereby removing antimony trioxide in the exhaust gas. In this way, not only can the antimony trioxide in the exhaust gas generated when preparing antimony-doped single crystal silicon be prevented from harming the human body, but also the antimony trioxide in the exhaust gas can be prevented from entering the inert gas recovery system and causing adverse effects on the entire inert gas recovery system. In addition, the antimony element generated in the exhaust gas treatment device for preparing antimony-doped single crystal silicon can fall freely under the action of gravity and enter the collector. This not only prevents the antimony element from undergoing secondary reactions in the exhaust gas treatment device for preparing antimony-doped single crystal silicon, but also the antimony element collected in the collector can be recycled, thereby reducing the consumption of antimony dopants in the process of preparing antimony-doped single crystal silicon.

[0034] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined. Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0035] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0036] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists, A and B exist at the same time, and B exists. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0037] In the description of the embodiments of the present application, the orientation or positional relationship indicated by the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the embodiments of the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present application. For example, if the device or element in the figure is inverted, then the element described as being "below" or "below" or "below" or "bottom" of other elements or features will be oriented "above" or "top" of the other elements or features. Therefore, the term "below" may cover both the above and below orientations depending on the context in which the term is used, which will be obvious to a person of ordinary skill in the art. The material may be oriented in other ways (e.g., rotated 90 degrees, inverted, flipped), and the spatially relative descriptors used herein may be interpreted accordingly.

[0038] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0039] In the accompanying drawings corresponding to the embodiments of the present application, the thickness and area of ​​the layers are exaggerated for better understanding and ease of description. In addition, when describing that a component is "substantially" formed on another component, it means that the component is not formed on the entire surface (or front surface) of the other component, nor is it formed on a partial edge of the entire surface.

[0040] In the description of the embodiments of the present application, when a certain component "includes" another component, unless otherwise specified, other components are not excluded, and other components may be further included. A second component is formed or provided above or on the first component, or a second component is formed or provided on the surface of the first component, or a second component is formed or provided on one side of the first component, which may include an embodiment in which the first component and the second component are in direct contact, and may also include an embodiment in which an additional component may be provided between the first component and the second component, so that the first component and the second component may not be in direct contact. For the sake of simplicity and clarity, various components may be drawn arbitrarily in different proportions. In the accompanying drawings, some layers / components may be omitted for simplicity. Unless otherwise specified, a second component is formed or provided on the surface of the first component, which means that the first component is in direct contact with the second component. Among them, the above-mentioned "component" may refer to a layer, a film, an area, a part, a structure, etc.

[0041] The terms used in the description of the various embodiments described herein are only used to describe specific embodiments and are not intended to be limiting. As used in the description of the various embodiments described and in the appended claims, "the components" are also intended to include plural forms unless the context clearly indicates otherwise. Among them, components include components such as layers, films, regions, or plates.

[0042] The following will describe the various embodiments of the present disclosure in detail with reference to the accompanying drawings. However, it will be appreciated by those skilled in the art that in the various embodiments of the present disclosure, many technical details are provided in order to enable the reader to better understand the present disclosure. However, even without these technical details and various changes and modifications based on the following embodiments, the technical solutions claimed in the present disclosure can be implemented.

[0043] The present invention provides a tail gas treatment device for preparing antimony-doped single crystal silicon. Figures 1 to 3 A preferred embodiment of the tail gas treatment device for preparing antimony-doped single crystal silicon provided by the present disclosure is shown.

[0044] See also Figures 1 to 3 The exhaust gas treatment device 100 for preparing antimony-doped single crystal silicon includes an equipment shell 1, a heater 2, a reducer 3 and a collector 4. The equipment shell 1 is provided with an exhaust gas inlet 11, and the exhaust gas inlet 11 is used to connect to the exhaust port of the single crystal furnace 200 so that the antimony-containing exhaust gas discharged from the single crystal furnace 200 can enter the equipment shell 1; the heater 2 is arranged on the equipment shell 1, and the heater 2 is used to heat the antimony-containing exhaust gas entering the equipment shell 1; the reducer 3 is arranged in the equipment shell 1, and the reducer 3 is used to react with antimony trioxide in the antimony-containing exhaust gas in the equipment shell 1 to generate antimony element; the collector 4 is detachably arranged on the equipment shell 1, and the collector 4 is located at the lower side of the reducer 3, and the collector 4 is used to collect the antimony element falling from the reducer 3.

[0045] Specifically, a gas channel 14 is formed inside the device housing 1, and an exhaust gas inlet 11 and an exhaust gas outlet 13 are provided on the device housing 1, and the exhaust gas inlet 11 and the exhaust gas outlet 13 are both connected to the gas channel 14. The exhaust gas inlet 11 of the device housing 1 is connected to the exhaust port of the single crystal furnace 200 through a pipeline, so that the antimony-containing exhaust gas generated by the single crystal furnace 200 when preparing antimony-doped single crystal silicon can enter the gas channel 14 of the device housing 1 from the exhaust gas outlet 13.

[0046] A heater 2 is provided on the device housing 1, and the antimony-containing tail gas in the gas channel 14 can be heated to a preset temperature by the heater 2. The preset temperature is usually 1000°C to 1100°C, for example, the preset temperature can be 1000°C, 1010°C, 1020°C, 1030°C, 1040°C, 1050°C, 1060°C, 1070°C, 1080°C, 1090°C or 1100°C.

[0047] The reducer 3 is arranged in the gas channel 14, so that a reduction reaction zone is formed in the equipment housing 1. The antimony-containing exhaust gas in the gas channel 14 flows to the reduction reaction zone and mixes with the reducer 3. The antimony-containing exhaust gas heated to a preset temperature by the heater 2 will undergo a reduction reaction with the reducer 3, and antimony trioxide in the antimony-containing exhaust gas will be reduced to antimony element at this temperature.

[0048] The collector 4 is open upward, the opening of the collector 4 is connected to the gas channel 14, and the collector 4 is located directly below the reducer 3, so that the antimony element generated in the reduction reaction zone can fall freely into the collector 4 under the action of gravity.

[0049] A reducer 3 is arranged in the equipment shell 1 of the exhaust gas treatment device 100 for preparing antimony-doped single crystal silicon, so that a reduction reaction zone is formed in the equipment shell 1. The antimony-containing exhaust gas generated by the single crystal furnace 200 when preparing antimony-doped single crystal silicon can enter the equipment shell 1 from the exhaust gas inlet 11. The antimony-containing exhaust gas entering the equipment shell 1 can flow to the reduction reaction zone and mix with the reducer 3. At the same time, the antimony-containing exhaust gas entering the equipment shell 1 is heated by the heater 2, so that the antimony trioxide in the antimony-containing exhaust gas undergoes a reduction reaction with the reducer 3 at high temperature to generate antimony element, thereby removing the antimony trioxide in the exhaust gas. This can not only prevent the antimony trioxide in the exhaust gas generated when preparing antimony-doped single crystal silicon from harming the human body, but also prevent the antimony trioxide in the exhaust gas from entering the inert gas recovery system and causing adverse effects on the entire inert gas recovery system. Furthermore, the antimony element generated in the exhaust gas treatment device 100 for preparing antimony-doped single crystal silicon can fall freely under the action of gravity and enter the collector 4. This not only prevents the antimony element from undergoing secondary reactions in the exhaust gas treatment device 100 for preparing antimony-doped single crystal silicon, but also the antimony element collected in the collector 4 can be recycled, thereby reducing the consumption of antimony dopants in the process of preparing antimony-doped single crystal silicon.

[0050] The embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings.

[0051] The inner shell wall of the device housing 1 is usually provided with a high temperature resistant material, so that the inside of the device housing 1 can be heated to a preset temperature or above the preset temperature by the heater 2. The specific shape of the device housing 1 can be set according to actual conditions. For example, the device housing 1 can be set in a tubular or furnace shape. Optionally, please refer to Figures 1 to 3 In some embodiments, the device housing 1 is arranged in a tubular shape, and an exhaust gas inlet 11 and an exhaust gas outlet 13 are arranged at both ends of the device housing 1. The device housing 1 is arranged in a tubular structure, so that the structure of the device housing 1 is simple and the volume is small. The following will take the device housing 1 arranged in a tubular shape as an example for description.

[0052] See also Figure 4 The tail gas inlet 11 of the equipment housing 1 is connected to the exhaust port of the single crystal furnace 200, and the tail gas outlet 13 of the equipment housing 1 is usually connected to the power pump 500, so that the tail gas treatment device 100 for preparing antimony-doped single crystal silicon is arranged on the connecting pipeline between the single crystal furnace 200 and the power pump 500, and the power pump 500 can transport the antimony-containing tail gas discharged from the single crystal furnace 200 to the tail gas treatment device 100 for preparing antimony-doped single crystal silicon. Optionally, please refer to Figures 1 to 3In some embodiments, the tail gas inlet 11 and the tail gas outlet 13 of the equipment housing 1 are both provided with connecting flanges 7. Thus, the connecting flanges 7 are provided at the tail gas inlet 11 and the tail gas outlet 13 of the tail gas treatment device 100 for preparing antimony-doped single crystal silicon, so that the tail gas treatment device 100 for preparing antimony-doped single crystal silicon is conveniently connected to the connecting pipeline between the single crystal furnace 200 and the power pump 500.

[0053] For further information, see Figures 1 to 3 In some embodiments, a sealing ring placement groove 71 is provided on the connection flange 7. Thus, by placing a sealing ring at the sealing ring placement groove 71 of the connection flange 7, the sealing performance at the tail gas inlet 11 and the tail gas outlet 13 of the tail gas treatment device 100 for preparing antimony-doped single crystal silicon can be improved.

[0054] Optionally, see Figure 4 In some embodiments, the exhaust gas treatment device 100 for preparing antimony-doped single crystal silicon also includes a filter tank 8, the inlet and outlet of the filter tank 8 are respectively connected to the exhaust port and the exhaust gas inlet 11 of the single crystal furnace 200, so that the antimony-containing exhaust gas discharged from the single crystal furnace 200 can enter the equipment housing 1 after passing through the filter tank 8.

[0055] Specifically, the filter tank 8 may be a part of the tail gas treatment device 100 for preparing antimony-doped single crystal silicon; the filter tank 8 may also not be a part of the tail gas treatment device 100 for preparing antimony-doped single crystal silicon, but a part of the preparation system 1000 of antimony-doped single crystal silicon. The filter tank 8 is arranged on the connecting pipeline between the single crystal furnace 200 and the tail gas treatment device 100 for preparing antimony-doped single crystal silicon. The antimony-containing tail gas discharged from the single crystal furnace 200 is filtered by the filter tank 8 to remove most of the solid impurities, and then enters the tail gas treatment device 100 for preparing antimony-doped single crystal silicon. The filter tank 8 can preliminarily filter the solid particles and impurities in the antimony-containing tail gas before the antimony-containing tail gas enters the tail gas treatment device 100 for preparing antimony-doped single crystal silicon.

[0056] The reducer 3 is provided with a carbon source, and the carbon source of the reducer 3 can react with antimony trioxide in the antimony-containing tail gas to undergo a reduction reaction. The specific style of the reducer 3 can be set according to actual conditions. Figures 1 to 3 In some embodiments, the reducer 3 includes a support frame 31 and a graphite carbon rod 32. Two support frames 31 are provided. The two support frames 31 are spaced apart from each other in the flow direction of the gas in the device housing 1. A plurality of graphite carbon rods 32 extending along the flow direction of the gas in the device housing 1 are provided between the two support frames 31.

[0057] Specifically, the graphite carbon rod 32 is used as the carbon source of the reducer 3 to provide the carbon required for the reduction reaction. The graphite carbon rod 32 can react with antimony trioxide in the antimony-containing tail gas to undergo a reduction reaction. Antimony trioxide reacts with carbon at high temperature to produce carbon monoxide gas and antimony element. The reaction equation is: Sb 2 O 3 +3C=2Sb+3CO. Both support frames 31 are circular hollow frames, and a plurality of graphite carbon rods 32 are arranged between the two support frames 31. Such arrangement of the reducer 3 not only makes the structure of the reducer 3 simpler, but also makes the gas antimony trioxide have a larger contact area with the carbon source when flowing through the reducer 3. Among them, the carbon monoxide gas can enter the dust removal tank through the pipeline to participate in the inert gas recovery process of the single crystal workshop.

[0058] The specific arrangement of the multiple graphite carbon rods 32 between the two support frames 31 can be set according to actual conditions. For example, the multiple graphite carbon rods 32 can be arranged in a circular, square or linear shape. Figures 1 to 3 In some embodiments, multiple graphite carbon rods 32 are arranged in multiple circles along the circumference of the device housing 1, so that the reducer 3 is configured as a mesh structure, which is beneficial to increase the contact area between the gas antimony trioxide and the carbon source when flowing through the reducer 3.

[0059] The graphite carbon rod 32 and the support frame 31 are usually detachably connected. Figures 1 to 3 In some embodiments, a slot is provided on the support frame 31, and one end of the graphite carbon rod 32 is inserted into the slot on the support frame 31. The two ends of the graphite carbon rod 32 are respectively inserted into the slots on the two support frames 31, so that the graphite carbon rod 32 is detachably arranged between the two support frames 31, so that the carbon source of the reducer 3 is easily disassembled and replaced.

[0060] Antimony trioxide reacts with the carbon source of the reducer 3 to generate antimony element, and the generated antimony element can fall freely into the collector 4 under the action of gravity. The collector 4 is located directly below the reducer 3. The collector 4 can be located inside the device housing 1 or outside the device housing 1. Optionally, please refer to Figures 1 to 3 In some embodiments, a collecting port 12 is provided on the device housing 1, and the collecting port 12 is located at the lower side of the reducer 3. The collector 4 is located outside the device housing 1, and the collector 4 is detachably provided at the collecting port 12.

[0061] Specifically, a downward collecting port 12 is provided on the lower shell wall of the equipment housing 1, and the collecting port 12 is connected to the gas channel 14, and the collecting port 12 is located directly below the reducer 3. When the collector 4 is arranged at the collecting port 12, the collector 4 can block the collecting port 12, and the antimony element falling from the reducer 3 can leave the equipment housing 1 from the collecting port 12 and enter the collector 4. After the tail gas treatment device 100 for preparing antimony-doped single crystal silicon has been working for a period of time, the collector 4 can be disassembled from the equipment housing 1, and the slag in the collector 4 can be recovered and the antimony element inside can be extracted. In this way, the collector 4 is arranged outside the equipment housing 1, which is convenient for disassembling and assembling the collector 4.

[0062] Optionally, see Figures 1 to 3 In some embodiments, the exhaust gas treatment device 100 for preparing antimony-doped single crystal silicon also includes a cooler 5, and the cooler 5 is arranged on the equipment housing 1 or the collector 4 corresponding to the reducer 3, and the cooler 5 is used to cool the generated antimony element and the unreacted gas in the equipment housing 1.

[0063] Specifically, after the reduction reaction between the antimony-containing tail gas and the reducer 3 is completed, the heater 2 stops heating, and at the same time, the product of the reduction reaction (i.e., antimony element and unreacted gas) is cooled to a safe handling temperature through the cooler 5. The cooler 5 can quickly cool down the antimony element generated by the reduction reaction.

[0064] The specific style of the cooler 5 may not be particularly limited. For example, the cooler 5 may be a liquid cooling device or an air cooling device. Figures 1 to 3 In some embodiments, the cooler 5 is a water cooling device, a water cooling pipe is arranged inside the cooler 5, and interfaces are arranged on both sides of the cooler 5 for water to enter on one side and exit on the other side.

[0065] The cooler 5 can be arranged on the device housing 1, or the cooler 5 can be arranged on the collector 4. Optionally, please refer to Figures 1 to 3 In some embodiments, the cooler 5 is disposed at the bottom of the collector 4 .

[0066] Specifically, the cooler 5 is located at the lower side of the collector 4, and the cooler 5 is in contact with the bottom of the collector 4. This not only allows the antimony element that falls into the collector 4 to be quickly cooled by the cooler 5, but also reduces the effect of the heat from the heater 2 on the cooler 5.

[0067] The heater 2 is disposed on the device housing 1. The heater 2 can be disposed on the shell wall of the device housing 1, or the heater 2 can be disposed in the gas channel 14 of the device housing 1. Optionally, please refer to Figures 1 to 3 In some embodiments, the heater 2 is disposed in the device housing 1 , and a heating power interface module 6 is disposed on the outer shell wall of the device housing 1 , and the heating power interface module 6 is electrically connected to the heater 2 .

[0068] Specifically, the heater 2 is arranged on the inner shell wall of the device housing 1, and the heating power interface module 6 is arranged on the outer shell wall of the device housing 1 corresponding to the heater 2, so that the heater 2 can be powered by the heating power interface module 6. The heating power interface module 6 and the device housing 1 can be welded to ensure the sealing of the device housing 1 at the heating power interface module 6.

[0069] The heating power interface module 6 can be located on the upper side, lower side or one side of the horizontal direction of the heater 2. Figures 1 to 3 In some embodiments, the heating power interface module 6 is located on the upper side of the heater 2, which makes it easy to connect the heating power interface module 6.

[0070] The specific shape of the heater 2 can be set according to actual conditions. For example, the heater 2 can be set in a ring shape, a spiral shape, or a cage shape. Figures 1 to 3 In some embodiments, the heater 2 is configured in a cylindrical shape that matches the shape of the device housing 1 .

[0071] Specifically, the heater 2 is configured as an annular drying tunnel heater, and the gas in the equipment housing 1 can pass through the heater 2 from the inner side of the heater 2. This not only reduces the resistance of the gas in the equipment housing 1 when passing through the heater 2, but also helps to increase the heating area of ​​the gas in the equipment housing 1 by the heater 2.

[0072] For further information, see Figures 1 to 3 In some embodiments, the heater 2 includes a heating unit 21 , which is extended along the extension direction of the device housing 1 , and a plurality of heating units 21 are arranged at intervals along the circumference of the device housing 1 .

[0073] The heating unit 21 can be a heating plate or a heating rod, etc., optionally, refer to Figures 1 to 3 In some embodiments, the heating unit 21 is a heating plate, which is arranged on the inner shell wall of the device shell 1, and the heating unit 21 is inclined in the direction away from the inner shell wall of the device shell 1. In this way, the heating plate is inclined relative to the radial direction of the device shell 1, which can increase the heating area of ​​the heater 2 on the gas in the device shell 1.

[0074] The specific location of the heater 2 on the device housing 1 can be set according to actual conditions. Figures 1 to 3 In some embodiments, the heater 2 is disposed in an area other than the reduction reaction area in the device housing 1 , so that the effect of the heat of the heater 2 on the cooler 5 can be reduced.

[0075] Optionally, see Figures 1 to 3 In some embodiments, two heaters 2 are respectively provided at the exhaust gas inlet 11 and the exhaust gas outlet 13 of the equipment housing 1 , and the reducer 3 is located between the two heaters 2 .

[0076] Specifically, two heaters 2 are provided, and the two heaters 2 are located at both ends of the equipment housing 1, and the reducer 3 is located between the two heaters 2, so that a reduction reaction zone is formed in the middle of the equipment housing 1, and the two heaters 2 do not extend into the reduction reaction zone, so that the influence of the heat of the two heaters 2 on the cooler 5 can be reduced. When the antimony-containing tail gas in the gas channel 14 is heated by the heater 2, the antimony-containing tail gas in the gas channel 14 can be heated by only one heater 2, for example, the antimony-containing tail gas in the gas channel 14 is heated by only the heater 2 located at the tail gas inlet 11, and the heater 2 located at the tail gas outlet 13 does not work; or the antimony-containing tail gas in the gas channel 14 can be heated by two heaters 2 at the same time.

[0077] Since two heaters 2 are respectively disposed at both ends of the equipment housing 1, the tail gas treatment device 100 for preparing antimony-doped single crystal silicon can be disposed on the connecting pipeline between the single crystal furnace 200 and the power pump 500 in a forward direction (i.e., the end of the equipment housing 1 provided with the tail gas inlet 11 is connected to the single crystal furnace 200) or a reverse direction (i.e., the end of the equipment housing 1 provided with the tail gas outlet 13 is connected to the single crystal furnace 200). At the same time, since two heaters 2 are disposed on the equipment housing 1, when one heater 2 fails, the antimony-containing tail gas in the gas channel 14 can still be heated by the other heater 2.

[0078] Optionally, in other embodiments, one heater 2 is provided, and the heater 2 is located at the tail gas inlet 11. In this way, when the antimony-containing tail gas enters the device housing 1 from the tail gas inlet 11, the antimony-containing tail gas can be heated by the heater 2.

[0079] When one heater 2 is provided, one heating power interface module 6 can be provided, for example, the one heating power interface module 6 is provided at one end of the equipment housing 1 close to the exhaust gas inlet 11; two heating power interface modules 6 can also be provided, for example, the two heating power interface modules 6 are respectively provided at the two ends of the equipment housing 1, so that the heater 2 can be selectively powered by any one of the two heating power interface modules 6.

[0080] Optionally, in some embodiments, the tail gas treatment device 100 for preparing antimony-doped single crystal silicon further includes a temperature controller, and the temperature controller is used to monitor and adjust the temperature inside the device housing 1 .

[0081] Optionally, in some embodiments, the exhaust gas treatment device 100 for preparing antimony-doped single crystal silicon further includes a gas flow controller, which is used to control the flow rate of the antimony-containing exhaust gas entering the device housing 1 to ensure efficient reaction.

[0082] Optionally, in some embodiments, the tail gas treatment device 100 for preparing antimony-doped single crystal silicon further includes a safety monitor, which may include temperature and pressure alarms to ensure safe operation.

[0083] The present disclosure also provides a system for preparing antimony-doped single crystal silicon. Figure 4 A preferred embodiment of the system for preparing antimony-doped single crystal silicon provided by the present disclosure is shown.

[0084] See also Figure 4 In some embodiments, a system 1000 for preparing antimony-doped single crystal silicon includes a tail gas treatment device 100 for preparing antimony-doped single crystal silicon, a single crystal furnace 200 and a gas treatment device 300. The single crystal furnace 200 is used to prepare antimony-doped single crystal silicon; the tail gas treatment device 100 for preparing antimony-doped single crystal silicon is the tail gas treatment device 100 for preparing antimony-doped single crystal silicon as described in the above embodiment, and the tail gas inlet 11 of the tail gas treatment device 100 for preparing antimony-doped single crystal silicon is connected to the exhaust port of the single crystal furnace 200; the air inlet of the gas treatment device 300 is connected to the tail gas outlet 13 of the tail gas treatment device 100 for preparing antimony-doped single crystal silicon, and the gas treatment device 300 is used to treat the gas discharged from the tail gas treatment device 100 for preparing antimony-doped single crystal silicon.

[0085] Specifically, since the tail gas treatment device 100 for preparing antimony-doped single crystal silicon adopts the technical solution of the above embodiment, it has the beneficial effects brought by the technical solution of the above embodiment. In the process of preparing antimony-doped single crystal silicon by using the single crystal furnace 200, dopants are added into the single crystal furnace 200. The dopants added into the single crystal furnace 200 may include only one dopant, namely, antimony dopant; the dopant added into the single crystal furnace 200 may also include multiple dopants, namely, antimony dopant and other dopant, i.e., mixed antimony element, for example, the dopant added into the single crystal furnace 200 includes antimony dopant and phosphorus dopant.

[0086] The gas treatment device 300 is usually an inert gas recovery system. The unreacted gas in the tail gas treatment device 100 for preparing antimony-doped single crystal silicon can be discharged from the tail gas outlet 13. The unreacted gas discharged from the tail gas treatment device 100 for preparing antimony-doped single crystal silicon will enter the gas treatment device 300. The unreacted gas can be treated by the gas treatment device 300 to remove the remaining harmful components in the unreacted gas to meet the emission or recovery standards.

[0087] Optionally, see Figure 4In some embodiments, the system 1000 for preparing antimony-doped single crystal silicon further includes a regulating valve 400, wherein the first end and the second end of the regulating valve 400 are respectively connected to the exhaust port of the single crystal furnace 200 and the exhaust gas inlet 11 of the exhaust gas treatment device 100 for preparing antimony-doped single crystal silicon, so that the exhaust gas inlet 11 of the exhaust gas treatment device 100 for preparing antimony-doped single crystal silicon is connected to the exhaust port of the single crystal furnace 200 through the regulating valve 400, and the third end of the regulating valve 400 is connected to the air inlet of the gas treatment device 300; wherein, when the system 1000 for preparing antimony-doped single crystal silicon is in a first exhaust state, the first end of the regulating valve 400 is connected to the second end, and the first end of the regulating valve 400 is disconnected from the third end; when the system 1000 for preparing antimony-doped single crystal silicon is in a second exhaust state, the first end of the regulating valve 400 is disconnected from the second end, and the first end of the regulating valve 400 is connected to the third end.

[0088] Specifically, the tail gas treatment device 100 for preparing antimony-doped single crystal silicon is connected to the single crystal furnace 200 through the regulating valve 400, and the regulating valve 400 may be a three-way valve, etc. When it is necessary to treat the tail gas containing antimony, the regulating valve 400 is controlled to adjust the preparation system 1000 of antimony-doped single crystal silicon to the first exhaust state, at which time the single crystal furnace 200, the tail gas treatment device 100 for preparing antimony-doped single crystal silicon, and the gas treatment device 300 are connected in sequence, and the tail gas discharged from the single crystal furnace 200 needs to be treated by the tail gas treatment device 100 for preparing antimony-doped single crystal silicon before entering the gas treatment device 300. When the carbon source needs to be checked or replaced, the regulating valve 400 is controlled to adjust the system 1000 for preparing antimony-doped single crystal silicon to the second exhaust state. At this time, the single crystal furnace 200 is disconnected from the tail gas treatment device 100 for preparing antimony-doped single crystal silicon, and the single crystal furnace 200 is directly connected to the gas treatment device 300. The tail gas discharged from the single crystal furnace 200 does not need to pass through the tail gas treatment device 100 for preparing antimony-doped single crystal silicon, and can directly enter the gas treatment device 300. In this way, during the re-investment or abnormal stage of the single crystal furnace 200, the regulating valve 400 can be controlled to adjust the system 1000 for preparing antimony-doped single crystal silicon to the second exhaust state, and then the carbon source can be checked or replaced, and the normal oxide discharge from the single crystal furnace 200 will not be affected.

[0089] Those skilled in the art can understand that the above-mentioned embodiments are specific examples for realizing the present disclosure, and in practical applications, various changes can be made to them in form and details without departing from the spirit and scope of the present disclosure. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present disclosure, so the protection scope of the present disclosure shall be based on the scope defined in the claims.

Claims

1. A tail gas treatment device for preparing antimony-doped single crystal silicon, characterized in that: include: An equipment housing, wherein the equipment housing is provided with an exhaust gas inlet, and the exhaust gas inlet is used to communicate with the exhaust port of the single crystal furnace so as to allow the antimony-containing exhaust gas discharged from the single crystal furnace to enter the equipment housing; A heater, the heater being disposed on the device housing and used for heating the antimony-containing tail gas entering the device housing; A reducer, the reducer is arranged in the device housing, and the reducer is used to generate antimony element by a reduction reaction with antimony trioxide in the antimony-containing tail gas in the device housing; A collector, wherein the collector is detachably mounted on the device housing, the collector is located at the lower side of the reducer, and the collector is used to collect the antimony element falling from the reducer.

2. The tail gas treatment device for preparing antimony-doped single crystal silicon according to claim 1, characterized in that: The tail gas treatment device for preparing antimony-doped single crystal silicon also includes a cooler, which is arranged on the equipment housing or the collector corresponding to the reducer, and is used to cool the generated antimony element and the unreacted gas in the equipment housing.

3. The tail gas treatment device for preparing antimony-doped single crystal silicon according to claim 2, characterized in that: The cooler is arranged at the bottom of the collector.

4. The tail gas treatment device for preparing antimony-doped single crystal silicon according to claim 1, characterized in that: A collecting port is provided on the device housing, and the collecting port is located at the lower side of the reducer. The collector is located outside the device housing, and the collector is detachably arranged at the collecting port.

5. The tail gas treatment device for preparing antimony-doped single crystal silicon according to claim 1, characterized in that: The device housing is provided with an exhaust gas outlet, the exhaust gas inlet and the exhaust gas outlet are respectively provided with two heaters, and the reducer is located between the two heaters; and / or, The heater is arranged in the device housing, and a heating power interface module is arranged on the outer shell wall of the device housing, and the heating power interface module is electrically connected to the heater.

6. The tail gas treatment device for preparing antimony-doped single crystal silicon according to claim 1, characterized in that: The heater is arranged in a cylindrical shape which matches the shape of the device shell.

7. The tail gas treatment device for preparing antimony-doped single crystal silicon according to claim 1, characterized in that: The reducer includes a support frame and graphite carbon rods. Two support frames are provided. The two support frames are spaced apart from each other in the flow direction of the gas in the device shell. A plurality of graphite carbon rods extending along the flow direction of the gas in the device shell are provided between the two support frames.

8. The tail gas treatment device for preparing antimony-doped single crystal silicon according to claim 1, characterized in that: The exhaust gas treatment device for preparing antimony-doped single crystal silicon also includes a filter tank, the inlet and outlet of which are respectively connected to the exhaust port of the single crystal furnace and the exhaust gas inlet, so that the antimony-containing exhaust gas discharged from the single crystal furnace passes through the filter tank and then enters the equipment housing.

9. A system for preparing single crystal silicon, characterized in that: include: A single crystal furnace, wherein the single crystal furnace is used to prepare antimony-doped single crystal silicon; An exhaust gas treatment device for preparing antimony-doped single crystal silicon, wherein the exhaust gas treatment device for preparing antimony-doped single crystal silicon is an exhaust gas treatment device for preparing antimony-doped single crystal silicon according to any one of claims 1 to 8, and the exhaust gas inlet of the exhaust gas treatment device for preparing antimony-doped single crystal silicon is connected to the exhaust port of the single crystal furnace; A gas treatment device, wherein the gas inlet of the gas treatment device is connected to the tail gas outlet of the tail gas treatment device for preparing antimony-doped single crystal silicon, and the gas treatment device is used to treat the gas discharged from the tail gas treatment device for preparing antimony-doped single crystal silicon.

10. The system for preparing single crystal silicon according to claim 9, characterized in that: The single crystal silicon preparation system further includes a regulating valve, wherein a first end and a second end of the regulating valve are respectively connected to an exhaust port of the single crystal furnace and an exhaust gas inlet of the exhaust gas treatment device for preparing antimony-doped single crystal silicon, so that the exhaust gas inlet of the exhaust gas treatment device for preparing antimony-doped single crystal silicon is connected to the exhaust port of the single crystal furnace through the regulating valve, and a third end of the regulating valve is connected to an air inlet of the gas treatment device; Among them, when the single crystal silicon preparation system is in a first exhaust state, the first end of the regulating valve is connected to the second end, and the first end of the regulating valve is disconnected from the third end; when the single crystal silicon preparation system is in a second exhaust state, the first end of the regulating valve is disconnected from the second end, and the first end of the regulating valve is connected to the third end.

Images