Anti-backflow device for tail gas of single crystal furnace and single crystal growth equipment

Abstract

This application provides an anti-backflow device for exhaust gas from a single crystal furnace and a single crystal growth device, comprising: a gas chamber having a cavity; an inlet end and an outlet end disposed on the gas chamber and communicating with the cavity within the gas chamber; and a check valve disposed within the gas chamber and rotatably connected to the outlet of the inlet end. When no gas flow enters the inlet end, the check valve closes the outlet of the inlet end; when gas flow enters the inlet end, the check valve opens the outlet of the inlet end. This application provides an anti-backflow device between the single crystal furnace and the filter tank. During normal operation, the exhaust gas flow entering the inlet end of the gas chamber pushes the check valve to open, allowing the exhaust gas to pass smoothly. When the butterfly valve or vacuum pump malfunctions, and no exhaust gas flow enters the inlet end, the check valve closes the outlet of the inlet end, effectively blocking the backflow path of the exhaust gas, preventing dust particles from entering the single crystal furnace chamber, protecting the growth environment of single crystal silicon, and reducing economic losses.

Description

Technical Field

[0001] This application relates to the field of semiconductor equipment technology, and more specifically to an anti-backflow device for exhaust gas from a single crystal furnace and a single crystal growth device. Background Technology

[0002] Monocrystalline silicon, as an important semiconductor material, is widely used in integrated circuits, solar cells, and other fields. Monocrystalline silicon is typically grown in a single crystal furnace using the Czochralski method. During the growth process, a large amount of exhaust gas containing silicon oxide dust is generated in the furnace chamber. This exhaust gas needs to be discharged and filtered in a timely manner to ensure the normal operation of the single crystal furnace and the growth quality of the monocrystalline silicon.

[0003] The exhaust gas treatment system of a single crystal furnace typically includes the single crystal furnace, a filter tank, a butterfly valve, and a vacuum pump connected in sequence. Under the negative pressure suction of the vacuum pump, the exhaust gas exits the single crystal furnace and enters the filter tank. The filter element inside the filter tank separates the silica dust from the exhaust gas, leaving the dust particles outside the filter element. The purified gas passes through the filter element and is discharged under the action of the vacuum pump. Furthermore, to regulate the pressure inside the single crystal furnace cavity, a butterfly valve is installed on the pipeline between the filter tank and the vacuum pump. The pressure inside the furnace cavity is precisely controlled by adjusting the opening degree of the butterfly valve.

[0004] However, in actual production, when the butterfly valve or vacuum pump suddenly malfunctions, the low-pressure environment inside the single crystal furnace chamber will be directly connected to the atmospheric environment at the exhaust gas outlet. Under atmospheric pressure, the exhaust gas will backflow, instantly spraying the silicon oxide and other dust particles separated in the filter tank, as well as the dust particles in the exhaust gas pipe, into the single crystal furnace chamber. This severely contaminates the hot zone components and silicon raw materials, destroys the growth environment of single crystal silicon, and causes the single crystal silicon to be unable to continue growing, resulting in significant economic losses.

[0005] Therefore, improvements are needed to at least partially address the aforementioned problems. Utility Model Content

[0006] The utility model description section introduces a series of simplified concepts, which will be further explained in detail in the detailed description section. This utility model description section is not intended to limit the key features and essential technical features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.

[0007] To at least partially solve the above problems, this utility model provides an anti-backflow device for tail gas from a single crystal furnace. The anti-backflow device comprises: a gas chamber having a cavity; an inlet end and an outlet end disposed on the gas chamber and communicating with the cavity within the gas chamber; and a check valve disposed within the gas chamber and rotatably connected to the outlet of the inlet end. When no airflow flows into the inlet end, the check valve closes the outlet of the inlet end; when airflow enters the inlet end, the check valve opens the outlet of the inlet end.

[0008] For example, the air intake end is composed of an air intake pipe, and the end face of the outlet of the air intake pipe is constructed as an inclined surface. Relative to the plane perpendicular to the axial direction of the air intake end, the inclined surface is inclined to the air inlet side of the air intake end. The check valve is provided corresponding to the end face, so that the check valve can close the outlet of the air intake end.

[0009] For example, the tilt angle of the inclined surface is 0 to 45 degrees relative to a plane perpendicular to the axial direction of the air intake end.

[0010] For example, the air inlet and the air outlet are axially aligned, and the air inlet and the air outlet are respectively located on opposite sides of the air chamber; or, the air inlet and the air outlet are axially perpendicular to each other, and the air inlet and the air outlet are respectively located on adjacent sides of the air chamber.

[0011] For example, the air chamber has at least one cleaning door, the air chamber is enclosed by a plurality of wall panels and the at least one cleaning door, the cleaning door is openably disposed on a wall panel on one side of the air chamber, for providing a passage to the internal cavity of the air chamber.

[0012] For example, the multiple wall panels of the air chamber include a top plate, a bottom plate, and at least two side plates, wherein the side plates are connected to the top plate and the bottom plate, and the cleaning door is rotatably connected to the top plate for closing the opening between the side plates of the air chamber.

[0013] For example, at least one hinge seat is provided at the position where the top plate is connected to the cleaning door, and the cleaning door is provided with at least one hinge ear corresponding to the hinge seat. The hinge seat and the hinge ear are connected by a pin, so that the cleaning door can rotate relative to the top plate about the pin. The number of hinge seats and hinge ears is the same, and the cleaning door is also provided with a handle component.

[0014] For example, a sealing gasket is provided at the joint between the cleaning door and the wall panel of the air chamber. When the air chamber is under negative pressure, the cleaning door presses the sealing gasket to achieve the sealing of the air chamber.

[0015] For example, the wall panel of the air chamber is provided with a groove at the position where it engages with the cleaning door, and the sealing gasket is partially disposed in the groove.

[0016] According to another aspect of this utility model, a single crystal growth apparatus is provided, comprising: a single crystal furnace; a filter tank having an inlet and an outlet for filtering exhaust gas discharged from the single crystal furnace; the aforementioned anti-backflow device for exhaust gas from the single crystal furnace, the anti-backflow device being installed in a pipeline between the single crystal furnace and the filter tank, wherein the inlet end of the anti-backflow device is connected to the outlet of the single crystal furnace, and the outlet end of the anti-backflow device is connected to the inlet of the filter tank; a butterfly valve, the inlet end of which is connected to the outlet of the filter tank; and a vacuum pump connected to the outlet end of the butterfly valve for providing negative pressure suction power.

[0017] According to this utility model, an anti-backflow device for tail gas from a single crystal furnace is installed between the single crystal furnace and the filter tank. During normal operation, the tail gas flow enters the inlet end of the gas chamber, pushing the check valve to open and allowing the tail gas to pass smoothly. When the butterfly valve or vacuum pump malfunctions and no tail gas flow enters the inlet end, the check valve closes the outlet of the inlet end, effectively blocking the tail gas backflow path, preventing dust particles from entering the single crystal furnace chamber, protecting the growth environment of single crystal silicon, and reducing economic losses. Attached Figure Description

[0018] The following drawings, which are incorporated herein by reference as part of this invention, are provided for understanding the invention. The drawings illustrate embodiments of the invention and their descriptions, serving to explain the principles of the invention.

[0019] In the attached image:

[0020] Figure 1 A schematic diagram of the anti-backflow device according to a specific embodiment of the present invention is shown;

[0021] Figure 2 A front view of an anti-backflow device according to a specific embodiment of the present invention is shown;

[0022] Figure 3 A schematic diagram of the anti-backflow device according to another specific embodiment of the present invention is shown;

[0023] Figure 4 A schematic diagram of the structure of a single crystal growth apparatus according to a specific embodiment of the present invention is shown. Detailed Implementation

[0024] In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention. However, it will be apparent to those skilled in the art that the present invention can be practiced without one or more of these details. In other instances, certain technical features well-known in the art have not been described in order to avoid confusion with the present invention.

[0025] It should be understood that this invention can be embodied in various forms and should not be construed as being limited to the embodiments set forth herein. Rather, providing these embodiments will make the disclosure thorough and complete, and will fully convey the scope of this invention to those skilled in the art. In the drawings, for clarity, the dimensions of layers and regions, as well as their relative dimensions, may be exaggerated. The same reference numerals denote the same elements throughout.

[0026] It should be understood that when an element or layer is referred to as "on," "adjacent to," "connected to," or "coupled to" other elements or layers, it may be directly on, adjacent to, connected to, or coupled to other elements or layers, or there may be intervening elements or layers. Conversely, when an element is referred to as "directly on," "directly adjacent to," "directly connected to," or "directly coupled to" other elements or layers, there are no intervening elements or layers. It should be understood that although the terms first, second, third, etc., may be used to describe various elements, components, areas, layers, and / or portions, these elements, components, areas, layers, and / or portions should not be limited by these terms. These terms are only used to distinguish one element, component, area, layer, or portion from another element, component, area, layer, or portion. Therefore, without departing from the teachings of this utility model, the first element, component, area, layer, or portion discussed below may be referred to as a second element, component, area, layer, or portion.

[0027] Spatial relation terms such as “below,” “under,” “below,” “under,” “above,” “above,” etc., are used herein for convenience of description to describe the relationship between one element or feature shown in the figure and other elements or features. It should be understood that, in addition to the orientation shown in the figure, spatial relation terms are intended to also include different orientations of the device in use and operation. For example, if the device in the figure is flipped, then the element or feature described as “below” or “under” the other element or feature will be oriented “above” the other element or feature. Therefore, the exemplary terms “below” and “under” can include both upper and lower orientations. The device may be otherwise oriented (rotated 90 degrees or otherwise) and the spatial descriptive terms used herein will be interpreted accordingly.

[0028] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the invention. When used herein, the singular forms “a,” “an,” and “the” are also intended to include the plural forms, unless the context clearly indicates otherwise.

[0029] To address at least one of the aforementioned technical problems, this application provides a backflow prevention device for single crystal furnace exhaust gas, comprising:

[0030] An air chamber, which contains a cavity;

[0031] The air inlet and air outlet are located on the air chamber and communicate with the cavity inside the air chamber.

[0032] A check valve is installed in the air chamber and rotatably connected to the outlet of the air inlet. When no airflow flows into the air inlet, the check valve closes the outlet of the air inlet. When airflow enters the air inlet, the check valve opens the outlet of the air inlet.

[0033] According to the anti-backflow device for tail gas of a single crystal furnace of this application, the anti-backflow device is installed between the single crystal furnace and the filter tank. During normal operation, the tail gas flow enters the gas chamber and pushes the check valve to open, allowing the tail gas to pass smoothly. When the butterfly valve or vacuum pump fails and no tail gas flow enters the gas chamber, the check valve closes the outlet of the gas chamber, which can effectively block the tail gas backflow path, prevent dust particles from entering the single crystal furnace chamber, protect the growth environment of single crystal silicon, and reduce economic losses.

[0034] To fully understand this application, a detailed structure will be presented in the following description to illustrate the technical solutions proposed in this application. Preferred embodiments of this application are described in detail below; however, in addition to these detailed descriptions, this application may have other implementation methods.

[0035] The following is for reference. Figures 1 to 3 A backflow prevention device for single crystal furnace exhaust gas according to an embodiment of this application is described, such as... Figures 1 to 3 As shown, the anti-backflow device 10 includes: an air chamber 11, which has a cavity; an air inlet 12 and an air outlet 13, which are disposed on the air chamber 11 and communicate with the cavity inside the air chamber 11; and a check valve 14, which is disposed inside the air chamber 11 and rotatably connected to the outlet of the air inlet 12. When no airflow flows into the air inlet 12, the check valve 14 closes the outlet of the air inlet 12. When airflow enters the air inlet 12, the check valve 14 opens the outlet of the air inlet 12.

[0036] In this embodiment, the anti-backflow device 10 includes an air chamber 11, an inlet end 12, an outlet end 13, and a check valve 14. The air chamber 11 is a cavity that can accommodate components such as the check valve 14, and can also accommodate dust particles from the backflowed exhaust gas. The air chamber 11 is provided with an inlet end 12 and an outlet end 13. The inlet end 12 is connected to the outlet of the single crystal furnace, receives the dust exhaust gas from the single crystal furnace, and guides it into the interior of the air chamber 11. The outlet end 13 is connected to a filter canister, and the outlet end 13 discharges the dust exhaust gas inside the air chamber 11 to the filter canister. The check valve 14 is disposed in the air chamber 11 and rotatably connected to the outlet of the inlet end 12, and the check valve 14 rotates around a horizontal axis. When there is no exhaust gas flow, that is, no airflow flows into the intake end 12, the check valve 14 is tightly fitted to the outlet of the intake end 12 due to its own gravity (that is, the check valve 14 is in the closed state), sealing the outlet of the intake end 12, blocking the backflow path of exhaust gas, and effectively preventing exhaust gas backflow; when there is exhaust gas flow, that is, airflow flows into the intake end 12, the airflow can directly act on the check valve 14 after entering from the intake end 12, generating sufficient thrust to push it open (that is, the check valve 14 is in the open state), and the airflow flows to the filter tank through the outlet end 13. Therefore, by installing the anti-backflow device of this application between the single crystal furnace and the filter tank, faults in the exhaust gas system such as butterfly valves and vacuum pumps can be repaired online, providing hardware support for the closed environment inside the single crystal furnace cavity. This allows for the rapid repair of hardware faults in the exhaust gas system such as butterfly valves and vacuum pumps during the crystal pulling process. After the fault is cleared, the check valve in the gas chamber of the anti-backflow device opens naturally as the pressure of the exhaust gas emission system decreases, allowing the crystal growth process to continue, protecting the growth environment of single crystal silicon and reducing economic losses.

[0037] In some embodiments, such as Figures 1 to 3 As shown, the anti-backflow device 10 includes a gas chamber 11 with a cavity inside. The cavity is used to accommodate components such as the check valve 14 and can also accommodate dust particles in the backflowed exhaust gas. Exemplarily, the gas chamber 11 also has at least one cleaning door 15. The cleaning door 15 allows operators to easily open the gas chamber 11 and clean the accumulated dust particles inside, thereby preventing the device itself from becoming a secondary pollution source. The gas chamber 11 is enclosed by multiple wall panels 16 and at least one cleaning door 15. The cleaning door 15 is openably mounted on one side of the wall panel of the gas chamber 11, providing a passage to the cavity inside the gas chamber 11. Specifically, when the single crystal furnace is operating normally, the gas chamber 11 is under negative pressure, and the cleaning door 15 naturally adheres to the gas chamber 11, making the gas chamber 11 a closed space. When the single crystal furnace stops operating, the gas chamber 11 is under normal pressure, and the cleaning door 15 can be freely opened for easy cleaning of the gas chamber 11.

[0038] In some embodiments, the multiple wall panels 16 of the air chamber 11 include a top plate 161, a bottom plate 162, and at least two side plates 163, which are connected to the top plate 161 and the bottom plate 162. Specifically, the air chamber 11 is a hollow three-dimensional structure enclosed by the top plate 161, the bottom plate 162, at least two side plates 163, and at least one cleaning door 15, with an internal cavity. The top plate 161 and the bottom plate 162 of the air chamber 11 are symmetrically arranged, with the top plate 161 located above the air chamber 11 and the bottom plate 162 located below the air chamber 11. The at least two side plates 163 are vertically connected between the top plate 161 and the bottom plate 162 to form the circumferential wall surface of the air chamber 11. The side plates 163 can be fixedly connected to the top plate 161 and the bottom plate 162 by welding or other means to ensure the structural strength and sealing performance of the air chamber. Alternatively, they can be connected by other means, which are not specifically limited. When the equipment is shut down for maintenance, a cleaning door 15 is installed on one side wall panel of the air chamber 11 to facilitate manual or mechanical cleaning. The number of cleaning doors 15 is determined by the number of side panels 163. When there are two side panels 163, there are two cleaning doors 15 on the air chamber 11; when there are three side panels 163, there is one cleaning door 15 on the air chamber 11. The selection is made according to the appropriate situation and no specific limitation is made.

[0039] Exemplarily, the cleaning door 15 is rotatably connected to the top plate 161 to close the opening between the side plates 163 of the gas chamber 11. The gas chamber 11 is enclosed by the top plate 161, the bottom plate 162, the side plates 163, and the cleaning door 15 to form a hollow three-dimensional structure. Designing the gas chamber 11 as a hollow three-dimensional structure with an internal cavity provides sufficient flow area to reduce gas flow resistance, provides space to accommodate the rotation trajectory of the check valve 14 in the open state, and other components, and can also collect dust particles (e.g., silicon oxide dust particles) carried by the backflow of exhaust gas in abnormal conditions to prevent them from entering the single crystal furnace cavity and affecting the growth environment of single crystal silicon.

[0040] In some embodiments, such as Figure 1As shown, at least one hinge seat 17 is provided at the position where the top plate 161 connects to the cleaning door 15. The cleaning door 15 is provided with at least one hinge ear 18 corresponding to the hinge seat 17. The hinge seat 17 and the hinge ear 18 are connected by a pin, allowing the cleaning door 15 to rotate relative to the top plate 161 around the pin, thereby opening and closing the air chamber. Exemplarily, the number of hinge seats 17 and hinge ears 18 are the same. In this embodiment, two hinge seats 17 are provided at the position where the top plate 161 connects to the cleaning door 15, with the two hinge seats 17 spaced apart. The cleaning door 15 is provided with two hinge ears 18 corresponding to the hinge seats 17. Each hinge seat 17 and hinge ear 18 are connected by a pin to ensure smooth rotation of the cleaning door 15. In other examples, the cleaning door 15 can also be rotatably connected to the top plate 161 by means of hinges or the like; this is not specifically limited.

[0041] In some embodiments, such as Figures 1 to 3 As shown, the anti-backflow device 10 includes an inlet end 12 and an outlet end 13, which are disposed on the gas chamber 11 and communicate with the cavity inside the gas chamber 11. Specifically, the inlet end 12 is connected to the gas outlet of the single crystal furnace and is used to receive the exhaust gas discharged from the furnace cavity of the single crystal furnace. The outlet end 13 is connected to the inlet of the filter tank and is used to guide the exhaust gas downstream for dust separation and further treatment. Together, they constitute the channel for gas transmission from the single crystal furnace to the exhaust gas system and are the input and output interfaces of the entire anti-backflow device 10.

[0042] In some embodiments, such as Figure 1 and Figure 2 As shown, the inlet end 12 and the outlet end 13 are axially aligned, and are respectively located on opposite sides of the air chamber 11. Specifically, when the axes of the inlet end 12 and the outlet end 13 are parallel or located on the same axis, they are respectively located on opposite side plates 163 of the air chamber 11 to form a straight airflow channel. For example, the inlet end 12 is located on the left side plate of the air chamber 11, and the outlet end 13 is located on the right side plate of the air chamber 11. This arrangement is suitable for exhaust gas systems where the exhaust pipe is a branch line, resulting in a short airflow path and low resistance.

[0043] In some embodiments, such as Figure 3As shown, the inlet end 12 and the outlet end 13 are perpendicular to each other, and are respectively located on adjacent sides of the gas chamber 11. Specifically, the axial direction of the inlet end 12 can be horizontal, and the axial direction of the outlet end 13 is perpendicular to the horizontal direction to form an "L"-shaped airflow path. The inlet end 12 and the outlet end 13 are respectively located on adjacent side plates 163 of the gas chamber 11. For example, the inlet end 12 is located on the left side plate of the gas chamber 11, and the outlet end 13 is located on the rear side plate of the gas chamber 11. The left and rear side plates are adjacent to each other, thus forming a natural airflow turning channel. Arranging the inlet and outlet ends perpendicular to each other effectively adapts to installation environments with limited space or requiring upward exhaust, reduces the use of internal and external bends, lowers system pressure loss and dust accumulation risks, improves the installation flexibility and system integration of the device under complex operating conditions, and also provides great convenience for cleaning operations within the single crystal furnace exhaust pipe.

[0044] In some embodiments, such as Figure 1 and Figure 2 As shown, the anti-backflow device includes a check valve 14, which is disposed within the gas chamber 11 and rotatably connected to the outlet of the inlet end 12. When no airflow enters the inlet end 12, the check valve 14 closes the outlet of the inlet end 12; when airflow enters the inlet end 12, the check valve 14 opens the outlet of the inlet end 12. In the event of tail gas backflow, the check valve 14 can trap dust particles in the tail gas within the gas chamber, preventing them from entering the single crystal furnace. Specifically, the check valve 14 can be rotatably connected to the outlet of the inlet end 12 via a rotating shaft. Both ends of the rotating shaft are fixed in bearing seats at the outlet position of the inlet end 12. The check valve 14 is sleeved on the rotating shaft, allowing it to rotate freely in a vertical plane, i.e., the check valve 14 can rotate up and down to open or close the outlet of the inlet end 12. When the single crystal furnace is normally venting exhaust gas, the exhaust gas flow generated by the negative pressure inside the furnace flows into the inlet end 12 of the gas chamber 11, acting on the check valve 14 and pushing it to rotate upwards (counterclockwise), meaning the check valve 14 is in the open state, opening the airflow channel and allowing the airflow to flow smoothly to the outlet end 13. When there is no exhaust gas flow, that is, no airflow enters the inlet end 12, the check valve 14, under its own gravity, fits tightly against the outlet of the inlet end 12, sealing the outlet of the inlet end, that is, the check valve 14 is in the closed state, thereby blocking the backflow path of the exhaust gas flow and effectively preventing exhaust gas backflow. For example, the shape of the check valve 14 matches the end face shape at the outlet of the inlet end 12 to facilitate a tight fit with the outlet of the inlet end. The check valve 14 achieves automatic check function under complex working conditions through a simple gravity-driven mechanism, and has significant advantages such as simple structure, rapid response, high reliability, and maintenance-free operation.

[0045] In some embodiments, such as Figure 2As shown, the air intake end 12 is composed of an air intake pipe. The end face of the air intake pipe outlet is constructed as an inclined surface. Relative to a plane perpendicular to the axial direction of the air intake end 12, the inclined surface is inclined towards the air intake port side of the air intake end 12. A check valve 14 is provided on the corresponding end face, so that the check valve 14 can close the outlet of the air intake end 12. Specifically, the inclined surface refers to the inclined cut of the end face at the air intake outlet to form an inclined surface that is not perpendicular to the axial direction of the air intake end 12, and the inclined surface is inclined towards the air intake port side of the air intake end 12. For example, the inclination angle A of the inclined surface relative to the plane perpendicular to the axial direction of the air intake end 12 is 0 degrees to 45 degrees, such as 0 degrees, 10 degrees, 20 degrees, 25 degrees, 35 degrees, or 45 degrees. Specifically, the shape of the inclined surface can be elliptical or other suitable shapes, and the shape of the check valve 14 matches the shape of the inclined surface. For example, the check valve 14 is an elliptical thin plate structure, which is not specifically limited.

[0046] In some embodiments, such as Figure 1 As shown, a sealing gasket 19 is provided at the joint between the cleaning door 15 and the wall panel of the gas chamber 11. When the gas chamber 11 is under negative pressure, the cleaning door 15 presses against the sealing gasket 19 to seal the gas chamber 11. Exemplarily, the wall panel 16 of the gas chamber 11 has a groove at the joint with the cleaning door 15, and the sealing gasket 19 is partially disposed within the groove. Specifically, a groove is provided on the wall panel 16 at the position where it engages with the cleaning door 15 to embed the sealing gasket 19. In the single crystal furnace working chamber, the gas chamber 11 is under negative pressure. At this time, the cleaning door 15 presses against the sealing gasket 19, thereby sealing the gas chamber 11 and enhancing its sealing performance. Exemplarily, the material of the sealing gasket can be a high-temperature resistant and corrosion-resistant material, such as fluorosilicone rubber (FVMQ) or perfluoroether rubber (FFKM), etc., without specific limitation.

[0047] In some embodiments, such as Figure 3 As shown, a handle component 151 is provided on the cleaning door 15, wherein the handle component 151 can be a ring-shaped hollow structure, etc. Specifically, the handle component 151 can be fixed to the cleaning door 15 by welding or other methods, and can withstand the force applied by the operator when opening or closing the cleaning door, facilitating the operator to clean the air chamber. Optionally, the handle component 151 can refer to the end opposite to the connection end between the cleaning door and the air chamber, or it can refer to other suitable positions. Specifically, the handle component 151 can be a closed ring with an "O-shape", "D-shape" or "U-shape" in shape, etc., without specific limitation. Optionally, the handle component 151 can also be integrally formed with the cleaning door.

[0048] For example, components such as the air chamber 11, air inlet 12, air outlet 13, check valve 14, and cleaning door 15 are made of 310S stainless steel. 310S stainless steel possesses excellent properties such as high temperature resistance and corrosion resistance, improving the reliability, safety, and service life of the anti-backflow device. In other examples, components such as the air chamber 11, air inlet 12 (e.g., composed of an air outlet pipe), air outlet 13, check valve 14, and cleaning door 15 can also be made of other suitable high temperature and corrosion-resistant materials; no specific limitation is made therein.

[0049] In summary, the backflow prevention device for single crystal furnace exhaust gas according to the embodiments of this application is installed between the single crystal furnace and the filter tank. During normal operation, the exhaust gas flow enters the inlet end and pushes the check valve to open, allowing the exhaust gas to pass smoothly. When the butterfly valve or vacuum pump fails and no exhaust gas flow enters the inlet end, the check valve closes the outlet of the inlet end, which can effectively block the backflow path of the exhaust gas, prevent dust particles from entering the single crystal furnace chamber, protect the growth environment of single crystal silicon, and reduce economic losses.

[0050] Example 2

[0051] This application also provides a single crystal growth apparatus, such as... Figure 4 As shown, it includes a single crystal furnace 21; a filter tank 22, which has an inlet and an outlet for filtering the exhaust gas discharged from the single crystal furnace 21; the aforementioned anti-backflow device 10 for the exhaust gas of the single crystal furnace, which is installed in the pipeline between the single crystal furnace 21 and the filter tank 22, wherein the inlet end of the anti-backflow device 10 is connected to the outlet of the single crystal furnace 21, and the outlet end of the anti-backflow device 10 is connected to the inlet of the filter tank 22; a butterfly valve 23, the inlet end of which is connected to the outlet of the filter tank 22; and a vacuum pump 24, which is connected to the outlet end of the butterfly valve 24 for providing negative pressure suction power.

[0052] According to the single crystal growth equipment of this application embodiment, an anti-backflow device is installed between the single crystal furnace and the filter tank. During normal operation, the exhaust gas flow enters the gas chamber and pushes the check valve to open, allowing the exhaust gas to pass smoothly. When the butterfly valve or vacuum pump fails and no exhaust gas flow enters the gas chamber, the check valve closes the outlet of the gas chamber, which can effectively block the exhaust gas backflow path, prevent dust particles from entering the single crystal furnace chamber, protect the growth environment of single crystal silicon, and reduce economic losses.

[0053] Although exemplary embodiments have been described herein with reference to the accompanying drawings, it should be understood that the above exemplary embodiments are merely illustrative and are not intended to limit the scope of this application. Various changes and modifications can be made therein by those skilled in the art without departing from the scope and spirit of this application. All such changes and modifications are intended to be included within the scope of this application as claimed in the appended claims.

[0054] Similarly, it should be understood that, in order to simplify this application and aid in understanding one or more aspects of the application, various features of this application may sometimes be grouped together in a single embodiment, figure, or description thereof in the description of exemplary embodiments of this application. However, this approach should not be construed as reflecting an intention that the claimed application requires more features than are expressly recited in each claim. Rather, as reflected in the corresponding claims, the point of application is that the corresponding technical problem can be solved with fewer features than all of a single disclosed embodiment. Therefore, the claims following the detailed description are hereby expressly incorporated into that detailed description, wherein each claim itself is a separate embodiment of this application.

[0055] Furthermore, those skilled in the art will understand that although some embodiments described herein include certain features but not others included in other embodiments, combinations of features from different embodiments are intended to be within the scope of this application and form different embodiments. For example, in the claims, any one of the claimed embodiments can be used in any combination.

[0056] It should be noted that the above embodiments are illustrative of this application and not limiting of it, and that those skilled in the art can devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses should not be construed as limiting the claims. The use of the words first, second, and third, etc., does not indicate any order. These words can be interpreted as names.

Claims

1. A backflow prevention device for exhaust gas from a single crystal furnace, characterized in that, The backflow prevention device includes: An air chamber, wherein the air chamber has a cavity; An air inlet and an air outlet are provided on the air chamber and communicate with the cavity inside the air chamber. A check valve is disposed in the air chamber and rotatably connected to the outlet of the air inlet. When no airflow flows into the air inlet, the check valve closes the outlet of the air inlet. When airflow enters the air inlet, the check valve opens the outlet of the air inlet.

2. The backflow preventing device according to claim 1, wherein The air intake end is composed of an air intake pipe, and the end face of the outlet of the air intake pipe is constructed as an inclined surface. Relative to the plane perpendicular to the axial direction of the air intake end, the inclined surface is inclined to the air inlet side of the air intake end. The check valve is provided corresponding to the end face, so that the check valve can close the outlet of the air intake end.

3. The backflow preventing device of claim 2, wherein The tilt angle of the inclined surface is 0 to 45 degrees relative to a plane perpendicular to the axial direction of the air intake end.

4. The backflow preventing device of claim 1, wherein The air inlet and the air outlet are axially aligned, and the air inlet and the air outlet are respectively located on opposite sides of the air chamber; or, the air inlet and the air outlet are axially perpendicular to each other, and the air inlet and the air outlet are respectively located on adjacent sides of the air chamber.

5. The backflow preventing device of claim 1, wherein The air chamber has at least one cleaning door, and the air chamber is enclosed by a plurality of wall panels and the at least one cleaning door. The cleaning door is openably disposed on a wall panel on one side of the air chamber to provide a passage to the internal cavity of the air chamber.

6. The anti-backflow device as described in claim 5, characterized in that, The air chamber has multiple wall panels including a top plate, a bottom plate, and at least two side plates, wherein the side plates are connected to the top plate and the bottom plate, and the cleaning door is rotatably connected to the top plate for closing the opening between the side plates of the air chamber.

7. The backflow preventing device of claim 6, wherein At least one hinge seat is provided at the position where the top plate is connected to the cleaning door. The cleaning door is provided with at least one hinge lug corresponding to the hinge seat. The hinge seat and the hinge lug are connected by a pin, so that the cleaning door can rotate relative to the top plate about the pin. The number of hinge seats and hinge lugs are the same. The cleaning door is also provided with a handle component.

8. The backflow preventing device of claim 5, wherein A sealing gasket is provided at the joint between the cleaning door and the wall panel of the air chamber. When the air chamber is under negative pressure, the cleaning door presses the sealing gasket to achieve a seal in the air chamber.

9. The anti-backflow device as described in claim 8, characterized in that, The wall panel of the air chamber has a groove at the position where it engages with the cleaning door, and the sealing gasket is partially disposed within the groove.

10. A single crystal growth apparatus, characterized by comprising: include: Single crystal furnace; A filter canister having an air inlet and an air outlet for filtering the exhaust gas discharged from the single crystal furnace; The backflow prevention device for tail gas of a single crystal furnace as described in any one of claims 1-9, wherein the backflow prevention device is installed in a pipeline between the single crystal furnace and the filter tank, wherein the inlet end of the backflow prevention device is connected to the outlet of the single crystal furnace, and the outlet end of the backflow prevention device is connected to the inlet of the filter tank. A butterfly valve, the inlet end of which is connected to the outlet of the filter canister; A vacuum pump, connected to the outlet end of the butterfly valve, is used to provide negative pressure suction power.

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