Airflow guiding device and semiconductor equipment

Abstract

The invention provides an airflow guiding device and semiconductor equipment. The airflow guiding device comprises a central column and spiral teeth. The central column is provided with two ends, one end is a gas forward inflow end, and the other end is a gas reverse inflow end. The spiral tooth is spirally wound on the central column, the spiral tooth is provided with two side surfaces, and one of the two side surfaces is a smooth surface and faces the gas forward flow-in end; and the stepped surface faces the gas reverse inflow end. The flow resistance of the gas flowing through the gas flow guiding device from the gas reverse inflow end is larger than the flow resistance of the gas flowing through the gas flow guiding device from the gas forward inflow end.

Description

TECHNICAL FIELD

[0001] The present application relates to a gas flow guiding structure, in particular to a gas flow guiding device for semiconductor equipment. BACKGROUND

[0002] In the field of semiconductor manufacturing, thin film deposition equipment with a dual-chamber design often faces the challenge of process gas cross-contamination. Specifically, when two reaction chambers are processing different processes in parallel, due to the gas passage connection between the chambers, some highly diffusive process gases may cause cross-contamination between the two chambers, causing the process gas of one chamber to penetrate into the other chamber, resulting in the composition of the thin film deviating from the design value. More seriously, during the cleaning cycle in the equipment maintenance phase, the backflow of cleaning gas due to the unbalanced flow resistance of the two chambers not only reduces the cleaning efficiency, but also may bring residual particles back to the cleaned area.

[0003] These two abnormal gas flow phenomena will directly cause the mismatching problem of the process parameters of the two chambers, which manifests as uneven film thickness, refractive index fluctuation and other defects, ultimately affecting the device yield.

[0004] To solve this problem, it is usually required that the process gases of the two chambers are basically separated, but during cleaning, the flow resistance of the cleaning gas to the two chambers cannot be affected, which puts high requirements on the pipeline layout. The existing mini gas valve (Mini Gas Valve) scheme can realize directional control of gas through a micro electromagnetic valve array, which can theoretically effectively isolate the gas flow of the two chambers, but this scheme not only causes a substantial increase in cost, but also increases the risk of forming particle pollution sources due to the need for a large number of rubber rings at the valve connection part.

[0005] Therefore, there is an urgent need for a gas flow guiding structure that can realize one-way conduction. SUMMARY

[0006] In order to overcome the defects of the prior art, the present application provides a gas flow guiding device and a semiconductor equipment with the same.

[0007] The present application provides a gas flow guiding device, comprising a center column and a screw thread. The center column has two ends, one end being a gas forward inflow end and the other end being a gas reverse inflow end. The screw thread is spirally wound on the center column, and the screw thread has two side surfaces, one of which is a smooth surface facing the gas forward inflow end; the other is a stepped surface facing the gas reverse inflow end. The flow resistance from the gas reverse inflow end through the gas flow guiding device is greater than the flow resistance from the gas forward inflow end through the gas flow guiding device.

[0008] In one embodiment, the screw thread is composed of a plurality of steps, the side surfaces of adjacent steps have a height difference, and the side surfaces of the plurality of steps form the stepped surface.

[0009] In one embodiment, the center column is a tapered cylinder, the cross-sectional diameter of the gas forward inflow end is smaller than that of the gas reverse inflow end.

[0010] In one embodiment, the center column is a standard cylinder, the cross-sectional diameter of both ends is the same.

[0011] In one embodiment, the gas flow guide device is disposed in the gas delivery pipe, the axis of the gas flow guide device is parallel to that of the gas delivery pipe, and a gas passage is formed between the gas flow guide device and the gas pipe.

[0012] In one embodiment, when the gas flows from the gas forward inflow end to the gas flow guide device, the gas flows along the gas passage to the gas reverse inflow end, and the gas spirally flows along the smooth surface of the screw thread around the center column.

[0013] In one embodiment, when the gas flows from the gas forward inflow end to the gas reverse inflow end, the width of the gas flow passage is the largest at the inlet, and then gradually decreases.

[0014] In one embodiment, when the gas flows from the gas reverse inflow end to the gas forward inflow end, the width of the gas flow passage is the smallest at the inlet, and then gradually increases.

[0015] In one embodiment, when the gas flows from the gas reverse inflow end to the gas forward inflow end, the width of the gas flow passage is the smallest at the inlet, and then gradually increases.

[0016] The present application also provides a semiconductor device with the gas flow guide device as described above. The semiconductor device comprises a first chamber, a second chamber, a cleaning gas generating source, a cleaning gas delivery pipeline, and a gas delivery pipe.

[0017] The cleaning gas generating source generates cleaning gas, which enters the gas delivery pipe through the cleaning gas delivery pipeline and is delivered to the first chamber and the second chamber, respectively.

[0018] The upstream of the gas delivery pipe is in communication with the cleaning gas delivery pipeline, and the downstream is in communication with the first chamber and the second chamber.

[0019] The gas flow guide device corresponding to each chamber is disposed in the gas delivery pipe.

[0020] The gas forward inflow end of each gas flow guide device is close to the cleaning gas delivery pipeline, and the gas reverse inflow end is close to the gas inlet of the first chamber or the second chamber.

[0021] In one embodiment, when a deposition process is performed, the gas flow guide device increases the flow resistance of the reverse flow of the process gas when the process gas flows through the gas flow guide device in the direction of the gas reverse inflow end, and reduces the gas crossflow phenomenon between the two chambers.

[0022] In one embodiment, when a cleaning process is performed, the gas flow guide device reduces the flow resistance of the cleaning gas and stabilizes the cleaning rate when the cleaning gas enters the gas delivery pipeline along the cleaning gas delivery pipeline and flows through the gas flow guide device in the direction of the gas forward inflow end.

[0023] The present application provides a gas flow guide device in a gas delivery pipeline, which is a spiral stepped flow guide column, and the gas flows spirally along the flow guide column screw thread. One side of the flow guide column spiral channel is a smooth curved surface, and the other side is a stepped surface, so that the flow resistance in one direction is significantly greater than that in the other direction, achieving a certain degree of one-way conduction. The advantage of this design is that when the gas flow guide device is arranged in the gas delivery pipeline of a semiconductor deposition device, during a deposition process, the process gas flows in the reverse direction through the gas flow guide device, and the flow resistance is high, thereby suppressing the gas crossflow phenomenon between the two chambers and slowing down the mismatch problem caused by the gas crossflow between the two chambers. During a cleaning process, the cleaning gas flows in the forward direction through the gas flow guide device, and the flow resistance is small, which has little effect on the cleaning rate. In addition, the spiral flow guide column also stabilizes the gas flow in the pipeline.

[0024] In addition, the central column of the gas flow guide device of the present application is a tapered cylinder, which has a small diameter on the forward flow side and a small diameter on the reverse flow side. When the gas flows in the forward direction through the gas flow guide device, the channel width at the inlet is large, and the gas flow resistance effect is weakened, and then the width changes from large to small, which can achieve rectification, and the flow loss is small. When flowing in the reverse direction, the effect is opposite. The tapered cylinder design of the present application can further increase the flow resistance difference between the forward and reverse directions. BRIEF DESCRIPTION OF DRAWINGS

[0025] The above summary of the application and the following detailed description of the application will be better understood when read in conjunction with the accompanying drawings. It should be noted that the drawings are only examples of the claimed application. In the drawings, the same reference numbers represent the same or similar elements.

[0026] Figure 1 A front view of a semiconductor device according to an embodiment of the present application is shown;

[0027] Figure 2 A schematic view of a gas flow guide device according to an embodiment of the present application is shown;

[0028] Figure 3a A schematic diagram of an airflow guiding device as seen from the forward gas inflow end according to an embodiment of the present invention is shown.

[0029] Figure 3b A schematic diagram of an airflow guiding device as seen from the reverse gas inflow end according to an embodiment of the present invention is shown.

[0030] Figure 4 A schematic diagram showing the parameters of an airflow guiding device according to an embodiment of the present invention is shown;

[0031] Figure 5 A static pressure distribution diagram according to an embodiment of the present invention is shown;

[0032] Figure 6a A simulation diagram of airflow mass flow rate within a prior art semiconductor device with a dual-cavity structure is shown.

[0033] Figure 6b A simulation diagram of airflow mass flow rate within a semiconductor device with a dual-cavity structure according to an embodiment of the present invention is shown. Detailed Implementation

[0034] The following detailed description of the features and advantages of the present invention provides sufficient information for any person skilled in the art to understand and implement the invention. Furthermore, based on the specification, claims, and drawings disclosed herein, those skilled in the art can easily understand the related objectives and advantages of the invention. Although the description of the invention is presented in conjunction with preferred embodiments, this does not mean that the features of the invention are limited to these embodiments. On the contrary, the purpose of describing the invention in conjunction with embodiments is to cover other options or modifications that may arise based on the claims of the invention. To provide a thorough understanding of the invention, numerous specific details will be included in the following description. The invention may also be implemented without using these details. Moreover, to avoid confusion or obscuring the focus of the invention, some specific details will be omitted in the description.

[0035] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0036] Furthermore, the terms "upper," "lower," "left," "right," "top," "bottom," "horizontal," and "vertical" used in the following description should be understood as the orientations shown in the relevant paragraphs and accompanying drawings. These relative terms are for illustrative purposes only and do not imply that the described apparatus must be manufactured or operated in a specific orientation, and therefore should not be construed as limiting the invention.

[0037] It is understood that while terms such as "first," "second," and "third" may be used herein to describe various components, channels, assemblies, regions, layers, and / or parts, these components, channels, assemblies, regions, layers, and / or parts should not be limited by these terms, and these terms are only used to distinguish different components, channels, assemblies, regions, layers, and / or parts. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0038] As indicated in this application and claims, unless the context clearly indicates otherwise, the words "a," "an," "an," and / or "the" are not specifically singular and may include plural forms. Generally speaking, the terms "comprising" and "including" only indicate the inclusion of explicitly identified steps and elements, which do not constitute an exclusive list, and the method or apparatus may also include other steps or elements.

[0039] In some embodiments, numbers describing the quantity of components and attributes are used. It should be understood that such numbers used in the description of embodiments are modified in some examples with the terms "approximately," "approximately," or "generally." Unless otherwise stated, "approximately," "approximately," or "generally" indicates that the numbers are allowed to vary by ±20%. Accordingly, in some embodiments, the numerical parameters used in the specification and claims are approximate values, which may be changed depending on the characteristics required by individual embodiments. In some embodiments, numerical parameters should take into account specified significant digits and employ a general method of digit reservation. Although the numerical ranges and parameters used to confirm their breadth of scope in some embodiments of this application are approximate values, in specific embodiments, such values ​​are set as precisely as feasible.

[0040] Furthermore, this application uses specific terms to describe embodiments of the application. For example, "an embodiment," "one embodiment," and / or "some embodiments" refer to a particular feature, structure, or characteristic related to at least one embodiment of the application. Therefore, it should be emphasized and noted that "an embodiment," "one embodiment," or "an alternative embodiment" mentioned twice or more in different locations in this specification do not necessarily refer to the same embodiment. In addition, certain features, structures, or characteristics in one or more embodiments of the application can be appropriately combined.

[0041] In the semiconductor manufacturing industry, thin-film deposition equipment with a dual-chamber design often faces the challenge of cross-contamination of process gases. Specifically, when two reaction chambers process different processes in parallel, due to the gas passage connection between the chambers, some highly diffusible process gases may cross-flow between the two chambers, causing process gases from one chamber to seep into the other, resulting in thin film composition deviating from design values. More seriously, during the cleaning cycle in the equipment maintenance phase, the cleaning gas may backflow due to the imbalance of flow resistance between the two chambers, not only reducing cleaning efficiency but also potentially carrying residual particles back to the cleaned area.

[0042] These two abnormal gas flow phenomena can directly cause mismatch in the process parameters of the two cavities, manifesting as defects such as uneven film thickness and refractive index fluctuations, ultimately affecting device yield.

[0043] Therefore, it is generally required that the process gases in the two chambers be essentially isolated, but during cleaning, the flow resistance of the cleaning gas to the two chambers must not be affected, which places stringent requirements on the piping layout. Existing mini gas valve solutions can achieve directional gas control through miniature solenoid valve arrays, theoretically effectively isolating the airflow between the two chambers. However, this solution not only significantly increases costs, but also increases the risk of particulate matter contamination sources due to the need for numerous rubber rings at the valve body connection points.

[0044] To address the aforementioned technical problems, this invention provides an airflow guiding structure.

[0045] Figure 1 A front view of a semiconductor device according to an embodiment of the present invention is shown. Figure 1 As shown, the semiconductor device includes a first chamber 101A, a second chamber 101B, a clean gas generation source 102, a clean gas delivery pipeline 106, and a gas delivery pipeline 103.

[0046] Clean gas source 102 generates clean gas 105, which enters gas delivery pipeline 103 through clean gas delivery pipeline 106 and is delivered to the first chamber 101A and the second chamber 101B respectively.

[0047] In one embodiment, the clean gas generation source 102 may be a remote plasma source (RPS).

[0048] The process gas is delivered to the first chamber 101A and the second chamber 101B for process treatment.

[0049] However, there are instances of back diffusion of some process gases, such as... Figure 1 Arrows 107A and 107B indicate the opposite flow direction of the process gas. This gas leakage phenomenon causes the process gas in one cavity to seep into another cavity, resulting in the film composition deviating from the design value.

[0050] The present invention provides an airflow guiding device 104 with a special structure for each chamber in the gas delivery pipeline 103.

[0051] The airflow guiding device 104 has two ends, one end near the clean gas delivery pipeline 106 and the other end near the air inlet of the process chambers 101A and 101B. The end near the clean gas delivery pipeline 106 is the gas forward inflow end, and the end near the air inlet of the process chambers 101A and 101B is the gas reverse inflow end. The direction of gas flow from the gas forward inflow end to the gas reverse inflow end is the gas forward flow direction, and the direction of gas flow from the gas reverse inflow end to the gas forward inflow end is the gas reverse flow direction.

[0052] During the deposition process, when the process gas flows through the airflow guide device 103 in the reverse flow direction, the airflow guide device 103 can increase the flow resistance of the process gas in the reverse flow direction and reduce the gas leakage phenomenon between the two chambers.

[0053] During the cleaning process, when the cleaning gas flows through the airflow guide device 103 along the cleaning gas delivery pipeline 106 in the forward flow direction, the airflow guide device 103 helps reduce the flow resistance of the cleaning gas while having a minimal impact on the cleaning rate. Furthermore, it also stabilizes the airflow within the pipeline.

[0054] Figure 2 A schematic diagram of an airflow guiding device according to an embodiment of the present invention is shown. The airflow guiding device includes a central column 201 and helical teeth 202 wound around the central column 201.

[0055] The airflow guiding device has two ends, one end near the clean gas delivery pipeline 106 and the other end near the air inlet of process chambers 101A and 101B. The end near the clean gas delivery pipeline 106 is the gas forward inflow end, and the end near the air inlet of process chambers 101A and 101B is the gas reverse inflow end. The direction of gas flow from the gas forward inflow end to the gas reverse inflow end is the gas forward flow direction, and the direction of gas flow from the gas reverse inflow end to the gas forward inflow end is the gas reverse flow direction.

[0056] The screw tooth 202 has two sides: one side is a smooth surface 203, and the other side is a stepped surface 204. The smooth surface 203 faces the gas inflow end 205. The stepped surface 204 faces the gas inflow end 206.

[0057] The screw tooth 202 consists of multiple steps. The sides of adjacent steps have a height difference. The sides of the multiple steps form the stepped surface 204. The stepped surface 204 can obstruct the airflow facing it.

[0058] When gas flows from the forward inflow end 205 through the airflow guide device, the gas spirals around the central column along the smooth surface of the screw teeth, with the flow direction indicated by the downward arrow. When gas flows from the reverse inflow end 206 through the airflow guide device, the gas spirals around the central column along the stepped surface of the screw teeth, with the flow direction indicated by the upward arrow. At this time, the gas flow is obstructed by the stepped surface of the screw teeth.

[0059] In one embodiment, the central column 201 is a standard cylinder with the same diameter at both ends.

[0060] In one embodiment, the central column 201 is a conical cylinder, and the cross-sectional diameter of the conical cylinder at the gas forward inflow end 205 is smaller than the cross-sectional diameter of the gas reverse inflow end 206.

[0061] Figure 3a A schematic diagram of an airflow guiding device, viewed from the forward gas inflow end, is shown according to an embodiment of the present invention. Figure 3a As shown, when gas flows from the gas inlet end 205 through the airflow guide device, the gas spirals around the central column along the smooth surface 203 of the screw teeth.

[0062] Figure 3b A schematic diagram of an airflow guiding device, viewed from the reverse gas inflow end, is shown according to an embodiment of the present invention. Figure 3b As shown, when the gas flows from the gas reverse inflow end 206 through the airflow guide device, the gas spirals around the central column along the stepped surface 204 of the screw teeth.

[0063] Figure 4 A schematic diagram of parameters for an airflow guiding device according to an embodiment of the present invention is shown. The helix angle corresponding to each step of the stepped surface 204 is θ. The diameter of the conical cylinder at the gas inflow end is d, and the diameter of the conical cylinder at the gas inflow end is D. The step height is h. The screw tooth height is H.

[0064] The screw teeth consist of multiple steps. The sides of adjacent steps have a height difference h (step height). The sides of the multiple steps form a stepped surface 204.

[0065] In one embodiment, the cross-sectional diameter d of the conical cylinder at the gas inflow end is smaller than the cross-sectional diameter D of the conical cylinder at the gas inflow end. This design further increases the flow resistance difference between the forward and reverse flows. When the gas flows forward (i.e., the gas flows from the gas inflow end to the gas inflow end), the inlet width of the airflow channel between the airflow guide device and the gas delivery pipe is the largest, reducing the airflow obstruction effect. Subsequently, the width gradually decreases, achieving rectification and minimizing flow losses. When the gas flows backward (i.e., the gas flows from the gas inflow end to the gas inflow end), the inlet width of the airflow channel between the airflow guide device and the gas delivery pipe is the smallest, resulting in a strong airflow obstruction effect and further reducing process gas leakage.

[0066] In one embodiment, the cross-sectional diameter d of the conical cylinder at the gas inflow end is 10~18mm.

[0067] In one embodiment, the cross-sectional diameter D of the conical cylinder at the gas inflow end is 15~23mm.

[0068] In one embodiment, the step height h is 0.6~0.8mm.

[0069] In one embodiment, the thread height H is 5~12mm.

[0070] In one embodiment, the helix angle θ is 10~20°.

[0071] In one embodiment, the pitch of the helix formed by the screw teeth of the airflow guiding device is 8~20 mm.

[0072] In one embodiment, the spiral formed by the screw teeth of the gas guiding device turns around the central column 8 to 20 times.

[0073] In one embodiment, the length of the gas guiding device is 100~165mm.

[0074] In one embodiment, the length of the gas guiding device is the same as the length of the horizontal pipe of the gas delivery pipe 103.

[0075] In one embodiment, the axial direction of the gas guiding device is parallel to the axial direction of the gas delivery pipe 103.

[0076] Figure 5 The diagram illustrates a static pressure distribution according to an embodiment of the present invention. The upper diagram shows the static pressure distribution for forward gas flow, and the lower diagram shows the static pressure distribution for reverse gas flow.

[0077] Figure 6a A simulation diagram of airflow mass flow rate within a prior art semiconductor device with a dual-cavity structure is shown. Figure 6bA simulation diagram of airflow mass flow rate within a semiconductor device with a dual-cavity structure according to an embodiment of the present invention is shown. The airflow guiding device of the present invention is disposed within the gas transmission channel of the semiconductor device.

[0078] Combination Figure 5 and compare Figure 6a and Figure 6b The simulation conclusions can be obtained as shown in Table 1 below, where the mass flow rate values ​​are... Figure 6a and Figure 6b Data was obtained from 601 monitoring points.

[0079]

[0080] Table 1

[0081] As shown in Table 1, the pressure drop increases by approximately 62% when the gas flows in reverse compared to forward flow. During the cleaning process, the pressure at the horizontal tube below the RPS increases by approximately 32%. During thin film deposition, the flow rate through the horizontal tube below the RPS decreases by 71%, and the process gas leakage phenomenon is significantly reduced.

[0082] The terminology and expressions used above are for descriptive purposes only, and the invention should not be limited to these terms and expressions. The use of these terms and expressions does not mean excluding any illustrative and descriptive equivalent features (or parts thereof), and it should be recognized that various modifications that may exist should also be included within the scope of the claims. Other modifications, variations, and substitutions may also exist. Accordingly, the claims should be considered to cover all such equivalents.

[0083] Similarly, it should be noted that, in order to simplify the description of the present application and thus aid in the understanding of one or more embodiments of the invention, the foregoing description of the embodiments of the present application sometimes combines multiple features into a single embodiment, drawing, or description thereof. However, this disclosure method does not imply that the subject matter of the present application requires more features than those mentioned in the claims.

[0084] Similarly, it should be noted that although the present invention has been described with reference to the specific embodiments described above, those skilled in the art should recognize that the above embodiments are only used to illustrate the present invention, and various equivalent changes or substitutions can be made without departing from the spirit of the present invention. Therefore, any changes or modifications to the above embodiments within the scope of the essential spirit of the present invention will fall within the scope of the claims of this application.

Claims

1. An airflow directing device, characterized in that, The application relates to a gas flow guide device, comprising: a central column having two ends, one end being a gas positive inflow end and the other end being a gas reverse inflow end; a helical thread wound on the central column, the thread having two sides, one side being a smooth surface and facing the gas positive inflow end, and the other side being a stepped surface and facing the gas reverse inflow end; wherein the flow resistance of the gas flow guide device from the gas reverse inflow end is greater than that from the gas positive inflow end.

2. The airflow directing device of claim 1, wherein, The thread is composed of a plurality of steps, the sides of adjacent steps having a height difference, and the sides of the steps form the stepped surface.

3. The airflow directing device of claim 1, wherein, The central column is a tapered cylinder, the cross-sectional diameter of the gas positive inflow end being smaller than that of the gas reverse inflow end.

4. The airflow directing device of claim 1, wherein, The central column is a standard cylinder, the cross-sectional diameters of the two ends being the same.

5. The airflow directing device of claim 1, wherein, The gas flow guide device is arranged in a gas conveying pipe, the axial direction of the gas flow guide device being parallel to that of the gas conveying pipe, and a gas passage being formed between the gas flow guide device and the gas conveying pipe.

6. The airflow directing device of claim 5, wherein, When the gas flows from the gas positive inflow end to the gas flow guide device, the gas flows along the gas passage to the gas reverse inflow end, and the gas spirally flows along the smooth surface of the thread around the central column.

7. The airflow directing device of claim 5, wherein, When the gas flows from the gas positive inflow end to the gas reverse inflow end, the width of the gas flow passage is the largest at the inlet and gradually decreases.

8. The airflow directing device of claim 5, wherein, When the gas flows from the gas reverse inflow end to the gas flow guide device, the gas flows along the gas passage to the gas positive inflow end, and the flow direction of the gas is towards the stepped surface of the thread, and the gas flow is hindered by the stepped surface.

9. The airflow directing device of claim 5, wherein, When the gas flows from the gas reverse inflow end to the gas positive inflow end, the width of the gas flow passage is the smallest at the inlet and gradually increases.

10. A semiconductor device having the gas flow guide according to any one of claims 1 to 9, characterized by The application further relates to a cleaning system, comprising: a first chamber, a second chamber, a cleaning gas generating source, a cleaning gas conveying pipeline and a gas conveying pipe; the cleaning gas generating source generates cleaning gas, which enters the gas conveying pipe through the cleaning gas conveying pipeline and is conveyed to the first chamber and the second chamber respectively; the upstream of the gas conveying pipe is communicated with the cleaning gas conveying pipeline, and the downstream is communicated with the first chamber and the second chamber; the gas flow guide device corresponding to each chamber is arranged in the gas conveying pipe; the gas positive inflow end of each gas flow guide device is close to the cleaning gas conveying pipeline, and the gas reverse inflow end is close to the gas inlet of the first chamber or the second chamber.

11. The semiconductor device of claim 10, wherein, When a deposition process is performed, the gas flow guide device increases the flow resistance of the process gas flowing in the reverse direction and reduces the gas leakage phenomenon between the two chambers.

12. The semiconductor device of claim 10, wherein, When a cleaning process is performed, the gas flow guide device reduces the flow resistance of the cleaning gas flowing along the cleaning gas conveying pipeline into the gas conveying pipe and through the gas flow guide device towards the gas positive inflow end, and stabilizes the cleaning rate.

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