Wafer cleaning equipment and method for semiconductor processing

Abstract

The invention relates to the technical field of semiconductor manufacturing, and discloses wafer cleaning equipment and method for semiconductor processing, the wafer cleaning equipment comprises a mounting frame body, a storage box is mounted on the inner side of the mounting frame body, one side of the top of the storage box is communicated with a cleaning box, and the inner side of the cleaning box is movably connected with a transmission shaft through a bearing; a plurality of rotating wheels are fixedly connected to the outer side of the transmission shaft, a motor for the transmission shaft to rotate is installed on the outer side of the cleaning box, a swing rod is fixedly connected to one end of the transmission shaft, and a connecting shaft is rotatably installed on the outer side of the swing rod. Air flow accurately acts on the surface of the wafer and a micropore area, bubbles in micropores are removed, and it is ensured that cleaning liquid can fully enter the micropores and remove dirt and pollutants in the micropores. According to the technology, the cleaning efficiency is remarkably improved, defects caused by incomplete cleaning are reduced, the surface quality of the wafer can be effectively improved, and the defective product rate in the follow-up process is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor manufacturing, and in particular to a wafer cleaning device and method for semiconductor processing. Background Art

[0002] Semiconductor wafers refer to silicon chips used to make silicon semiconductor circuits. Since a large amount of free matter, oxides or dust will adhere to the surface of semiconductor wafers during production and use, and these free matter, oxides or dust will affect the normal use of semiconductor wafers and shorten their service life, it is very necessary to clean semiconductor wafers.

[0003] In the prior art, semiconductor wafers are mostly cleaned by placing the semiconductor wafer to be cleaned into a cleaning tank for cleaning, and then draining and air-drying it after cleaning. The above cleaning method is to place the semiconductor wafer into a cleaning tank filled with cleaning liquid and sink it to the bottom of the tank. However, there are a group of micropores evenly distributed on the semiconductor wafer, so bubbles may exist in the micropores during the process of placing the semiconductor wafer into the cleaning tank, resulting in the micropores with bubbles being unable to be cleaned during cleaning, so there is a problem of incomplete cleaning.

[0004] To this end, those skilled in the art have proposed a wafer cleaning device and method for semiconductor processing to solve the above problems. Summary of the invention

[0005] In view of the deficiencies in the prior art, the present invention provides a wafer cleaning device and method for semiconductor processing, which solves the problems raised in the above-mentioned background technology.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solutions: a wafer cleaning device and method for semiconductor processing, comprising a mounting frame, a storage box is installed on the inner side of the mounting frame, a top side of the storage box is connected to a cleaning box, the inner side of the cleaning box is movably connected with a transmission shaft through a bearing, the outer side of the transmission shaft is fixedly connected with a plurality of rotating wheels, a motor for rotating the transmission shaft is installed on the outer side of the cleaning box, one end of the transmission shaft is fixedly connected with a swing rod, the outer side of the swing rod is rotatably installed with a connecting shaft, the outer side of the cleaning box is fixedly connected with a fixed cylinder, the interior of the fixed cylinder is slidably connected with a movable rod, the outer side of the fixed cylinder is connected with a connecting pipe, one end of the connecting pipe is fixedly connected with a serpentine jet pipe, and the inner side of the serpentine jet pipe is provided with a plurality of nozzles.

[0007] Preferably, one side of the top of the storage box is fixedly connected to a limit frame and a mounting shell in sequence, the limit frame is slidably connected to a movable frame inside, the mounting shell is rotatably connected to a driving impeller inside, the outer side of the driving impeller is fixedly connected to a swing shaft, the inner side of the mounting frame is detachably connected to a filter screen, the inner wall of the mounting frame is fixedly connected to two limit plates, the inner side of the limit plate is slidably connected to a rack plate, the outer side of the rack plate is fixedly connected to a fixed plate, the inner side of the fixed plate is elastically connected to a scraper via a plurality of springs, and a driving gear is rotatably installed inside the storage box via a rotating shaft.

[0008] Preferably, the outer sides of the two rack plates are meshedly connected with the outer side of the driving gear, the bottom end of the movable frame is fixedly connected with the outer side of one of the limit plates, and the outer surface of the fixed plate is in contact with the outer surface of the filter.

[0009] Preferably, one end of the connecting shaft away from the swing rod is rotatably connected to one end of the movable rod, the outside of the fixed cylinder is connected to an air intake pipe, and one-way valves are installed inside the air intake pipe and the connecting pipe, and the conduction directions of the two one-way valves are opposite.

[0010] Preferably, a plurality of supporting wheels are installed on the inner side of the cleaning box, and the supporting wheels are used to place wafers.

[0011] Preferably, the outside of the mounting shell is connected in sequence with a first connecting pipe and a second connecting pipe, one end of the first connecting pipe is connected to the outside of the storage box, and the other end of the second connecting pipe is connected to the outside of the cleaning box through a transport assembly.

[0012] Preferably, the transport component includes a pump body, which is installed on one side of the top of the storage box, and pipes are installed at the output end and the input end of the pump body, one of the pipes is connected to one side of the second connecting pipe, and the other pipe is fixedly connected to a spray pipe, and the spray pipe is fixedly connected to the inside of the cleaning box.

[0013] A method for using a wafer cleaning device for semiconductor processing comprises the following steps:

[0014] Step 1: placing the semiconductor wafer to be cleaned in the groove inside the multiple movable rods, and then starting the motor to drive the transmission shaft to rotate, so that the multiple rotating wheels rotate, and the multiple semiconductor wafers rotate synchronously;

[0015] Step 2: Start the pump to transport the cleaning liquid in the storage box to the inside of the snake-shaped spray pipe through two pipes, and spray the cleaning liquid onto the outer surfaces of multiple semiconductor wafers through the spray pipe to clean them;

[0016] Step 3: As the transmission shaft rotates, the swinging rod will be driven to rotate. At this time, under the action of the traction force of the connecting shaft, the movable rod reciprocates left and right along the inside of the fixed cylinder, so that the air pressure inside the fixed cylinder changes continuously and generates airflow. The airflow is transported to the serpentine jet pipe through the connecting pipe, and the airflow is sprayed on the outer surface of the semiconductor wafer through the nozzle of the serpentine jet pipe, and the airflow is used to remove bubbles on the micropores of the semiconductor wafer;

[0017] Step 4. When the cleaning liquid is transported to the inside of the serpentine jet pipe through the pump body, the cleaning liquid will pass through the driving impeller inside the mounting shell, and the flow of water will drive the driving impeller to rotate, thereby driving the swing shaft to rotate synchronously. Since the end of the swing shaft moves along the inside of the movable groove, the movable frame reciprocates left and right along the inner wall of the limit frame, further driving the upper rack plate to move synchronously. At this time, the lower rack plate will move in the opposite direction of the upper rack plate as the driving gear rotates, and then the two fixed plates will reciprocate left and right, and the scraper will be used to scrape off the dirt on the outer surface of the filter.

[0018] The present invention provides a wafer cleaning device and method for semiconductor processing, which has the following beneficial effects:

[0019] 1. The present invention removes bubbles in the micropores by precisely applying airflow to the wafer surface and micropore area, ensuring that the cleaning liquid can fully enter the micropores and remove dirt and pollutants therein. This technology not only significantly improves the cleaning efficiency and reduces defects caused by incomplete cleaning, but also effectively improves the surface quality of the wafer and reduces the defective product rate in subsequent processes.

[0020] 2. The present invention can rotate the wafer during the cleaning process, avoiding the cleaning dead corners that may occur in traditional cleaning methods, ensuring that every part of the wafer surface can be evenly affected by the cleaning liquid. At the same time, the spraying of the cleaning liquid is combined with the rotation of the impeller to effectively drive the scraper in the cleaning component to move back and forth, ensuring that the dirt on the filter plate can be scraped off in a timely and thorough manner, avoiding the accumulation of dirt from interfering with the cleaning process. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A perspective view of the present invention;

[0022] Figure 2 It is a schematic diagram of the cleaning box structure of the present invention;

[0023] Figure 3 It is a schematic diagram of the limit frame structure of the present invention;

[0024] Figure 4 It is a schematic diagram of the swing arm structure of the present invention;

[0025] Figure 5It is a schematic diagram of the structure of the limiting plate of the present invention;

[0026] Figure 6 It is a schematic diagram of the filter structure of the present invention;

[0027] Figure 7 It is a cross-sectional view of the fixing plate of the present invention.

[0028] Among them, 1. installation frame; 2. storage box; 3. cleaning box; 4. installation shell; 501. first connecting pipe; 502. second connecting pipe; 601. movable frame; 602. limiting frame; 603. driving impeller; 604. swing shaft; 605. limiting plate; 606. driving gear; 607. rack plate; 608. filter screen; 609. fixed plate; 610. scraper; 7. supporting wheel; 801. serpentine jet pipe; 802. transmission shaft; 803. rotating wheel; 804. swing rod; 805. connecting shaft; 806. connecting pipe; 807. fixed cylinder; 808. movable rod; 9. spray pipe. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the specification of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] Please see attached Figure 1 - Attachment Figure 7 The embodiment of the present invention provides a wafer cleaning device for semiconductor processing, including a mounting frame 1, a storage box 2 is mounted on the inner side of the mounting frame 1, a cleaning box 3 is connected to the top side of the storage box 2, a transmission shaft 802 is movably connected to the inner side of the cleaning box 3 through a bearing, a plurality of rotating wheels 803 are fixedly connected to the outer side of the transmission shaft 802, a motor for rotating the transmission shaft 802 is mounted on the outer side of the cleaning box 3, a swing rod 804 is fixedly connected to one end of the transmission shaft 802, a connecting shaft 805 is rotatably mounted on the outer side of the swing rod 804, a fixed cylinder 807 is fixedly connected to the outer side of the cleaning box 3, a movable rod 808 is slidably connected to the interior of the fixed cylinder 807, a connecting pipe 806 is connected to the outer side of the fixed cylinder 807, a serpentine jet pipe 801 is fixedly connected to one end of the connecting pipe 806, and a plurality of nozzles are arranged on the inner side of the serpentine jet pipe 801. One end of the connecting shaft 805 away from the swing rod 804 is rotatably connected to one end of the movable rod 808. The outside of the fixed cylinder 807 is connected to an air intake pipe. Both the air intake pipe and the connecting pipe 806 are equipped with one-way valves, and the conduction directions of the two one-way valves are opposite.

[0031] Specifically, the mounting frame 1 provides basic support for the entire cleaning equipment. Its design ensures the stability of the equipment and the fixation of each component, while also providing a reasonable layout and connection space for each internal component. The storage box 2 is used to store cleaning liquid. One side of the top of the storage box 2 is connected to the cleaning box 3, and the cleaning box 3 carries the liquid transmission during the cleaning process. To ensure the continuous rotation of the transmission shaft 802, a motor is installed on the outside of the cleaning box 3. The motor provides power to the transmission shaft 802, and the speed of the motor can be adjusted according to the cleaning requirements. The rotation of the transmission shaft 802 is not only the driving source during the cleaning process, but also provides power for the subsequent swing rod 804.

[0032] The rotation of the swing rod 804 and the connecting shaft 805 drives the movable rod 808 to slide inside the fixed cylinder 807. The fixed cylinder 807 provides a stable sliding track for the movable rod 808. The left and right reciprocating motion of the movable rod 808 causes the air pressure inside the fixed cylinder 807 to change. When the movable rod 808 moves to the left along the inside of the fixed cylinder 807, the one-way valve located in the air intake pipe is closed, and the one-way valve inside the connecting pipe 806 is opened, and the air flow enters the inside of the connecting pipe 806. When the movable rod 808 moves to the right along the inside of the fixed cylinder 807, the one-way valve located in the air intake pipe is opened, and the one-way valve inside the connecting pipe 806 is closed, and the external air enters the inside of the fixed cylinder 807 through the air intake pipe.

[0033] The outside of the fixed cylinder 807 is connected to a connecting pipe 806, which guides the airflow from the inside of the fixed cylinder 807 to the serpentine jet pipe 801. The design of the serpentine jet pipe 801 makes full use of the curved structure, so that the airflow can cover a wider range of the wafer surface during the jetting process. The multi-nozzle design of the serpentine jet pipe 801 allows the airflow to be evenly and accurately sprayed onto the wafer surface, achieving the purpose of efficiently removing bubbles.

[0034] The outside of the fixed cylinder 807 is connected to the air inlet pipe, which is responsible for delivering the external air source to the inside of the cleaning system. A one-way valve is installed in the air inlet pipe, which controls the direction of the airflow, avoids airflow backflow or unstable flow, and ensures that the airflow flows smoothly from the inside of the fixed cylinder 807 into the connecting pipe 806 and continues to be delivered to the serpentine jet pipe 801. There are two one-way valves in the device, and the conduction directions of the two one-way valves are opposite, so as to accurately control the in and out of the airflow and ensure the stability of the airflow in the system.

[0035] As the motor drives the transmission shaft 802 to rotate, the transmission shaft 802 drives the multiple rotating wheels 803 to rotate, and then drives the swing rod 804 to rotate. The swing rod 804 pushes the movable rod 808 to do left and right reciprocating motion along the inside of the fixed cylinder 807 through the traction force of the connecting shaft 805. The left and right sliding of the movable rod 808 causes the air pressure inside the fixed cylinder 807 to change periodically, and the air pressure fluctuation generates airflow. The airflow is transported to the serpentine jet tube 801 through the connecting tube 806. In this way, the airflow is transported to the nozzle of the serpentine jet tube 801 with a relatively uniform pressure and flow rate. The multiple nozzles of the serpentine jet tube 801 spray the airflow onto the surface of the semiconductor wafer. The airflow is sprayed through the nozzle with a high speed and impact force, which can effectively remove bubbles on the wafer surface and in the micropores.

[0036] The top side of the storage box 2 is fixedly connected with the limit frame 602 and the installation shell 4 in sequence, the limit frame 602 is slidably connected with the movable frame 601 inside, the installation shell 4 is rotatably connected with the driving impeller 603 inside, the outer side of the driving impeller 603 is fixedly connected with the swing shaft 604, the inner side of the installation frame body 1 is detachably connected with the filter screen 608, the inner wall of the installation frame body 1 is fixedly connected with two limit plates 605, the inner side of the limit plate 605 is slidably connected with the rack plate 607, the outer side of the rack plate 607 is fixedly connected with the fixed plate 609, the inner side of the fixed plate 609 is elastically connected with the scraper 610 through multiple springs, and the inside of the storage box 2 is rotatably installed with the driving gear 606 through the rotating shaft. The outer sides of the two rack plates 607 are meshed and connected with the outer sides of the driving gear 606, the bottom end of the movable frame 601 is fixedly connected with the outer side of one of the limit plates 605, and the outer surface of the fixed plate 609 is in contact with the outer surface of the filter screen 608.

[0037] Specifically, a filter screen 608 is detachably connected to the inner side of the mounting frame 1. The outer surface of the filter screen 608 is directly in contact with the scraper 610 during the cleaning process. The scraper 610 is connected to the fixed plate 609 through the elastic action of multiple springs, and can perform scraping work on the surface of the filter screen 608 according to the action of the springs. The fixed plate 609 is connected to the rack plate 607, and the outer side of the rack plate 607 is meshed with the driving gear 606 through the rack, thereby pushing the scraper 610 to perform the cleaning action.

[0038] The driving impeller 603 is driven to rotate by the flow of water, thereby driving the swing shaft 604 to rotate synchronously. The swing shaft 604 drives the movable frame 601 to reciprocate left and right along the inner wall of the limiting frame 602, thereby pushing the rack plate 607 to move synchronously. The rack plate 607 is meshed with the driving gear 606, and the movement direction of the rack plate 607 is synchronized with the opposite direction of the upper rack plate 607, finally realizing the left and right reciprocating motion of the fixed plate 609, and the dirt on the surface of the filter screen 608 is removed by the scraper 610. The limiting frame 602 and the limiting plate 605 play a role in controlling the range of motion. The limiting frame 602 is connected to the movable frame 601 by sliding, limiting its movement within a certain range to ensure the stability and accuracy of the cleaning process. The limiting plate 605 is connected to the rack plate 607 by sliding to ensure the correct movement path of the rack plate 607.

[0039] A plurality of supporting wheels 7 are installed inside the cleaning box 3, and the supporting wheels 7 are used to place wafers. The outside of the mounting shell 4 is connected with a first connecting pipe 501 and a second connecting pipe 502 in sequence, one end of the first connecting pipe 501 is connected with the outside of the storage box 2, and the other end of the second connecting pipe 502 is connected with the outside of the cleaning box 3 through a transport assembly. The transport assembly includes a pump body, which is installed on one side of the top of the storage box 2. Pipes are installed at both the output and input ends of the pump body, one of which is connected with one side of the second connecting pipe 502, and the other is fixedly connected with a liquid spraying pipe 9, which is fixedly connected to the inside of the cleaning box 3.

[0040] Specifically, by starting the pump body, the liquid in the storage tank 2 is introduced into the liquid spraying pipe 9 through the first connecting pipe 501 , the second connecting pipe 502 and the two pipelines.

[0041] A method for using a wafer cleaning device for semiconductor processing comprises the following steps:

[0042] Step 1: Place the semiconductor wafers to be cleaned in the grooves inside the multiple movable rods 808, and then start the motor to drive the transmission shaft 802 to rotate, so that the multiple rotating wheels 803 rotate, and the multiple semiconductor wafers rotate synchronously;

[0043] Step 2: Start the pump to transport the cleaning liquid inside the storage box 2 to the inside of the serpentine jet pipe 801 through two pipes, and spray the cleaning liquid onto the outer surfaces of multiple semiconductor wafers through the liquid spray pipe 9 to clean them;

[0044] Step 3: As the transmission shaft 802 rotates, the swing rod 804 will be driven to rotate. At this time, under the traction of the connecting shaft 805, the movable rod 808 reciprocates left and right along the inside of the fixed cylinder 807, so that the air pressure inside the fixed cylinder 807 changes continuously and generates airflow. The airflow is transported to the serpentine jet pipe 801 through the connecting pipe 806, and the airflow is sprayed on the outer surface of the semiconductor wafer through the nozzle of the serpentine jet pipe 801, and the airflow is used to remove bubbles on the micropores of the semiconductor wafer;

[0045] Step 4. When the cleaning liquid is transported to the inside of the serpentine jet pipe 801 through the pump body, the cleaning liquid will pass through the driving impeller 603 inside the mounting shell 4. The flow of water will drive the driving impeller 603 to rotate, thereby driving the swing shaft 604 to rotate synchronously. Since the end of the swing shaft 604 moves along the inside of the movable groove, the movable frame 601 reciprocates left and right along the inner wall of the limit frame 602, further driving the upper rack plate 607 to move synchronously. At this time, the lower rack plate 607 will move in the opposite direction of the upper rack plate 607 as the driving gear 606 rotates, and then the two fixed plates 609 reciprocate left and right, and the scraper 610 is used to scrape off the dirt on the outer surface of the filter screen 608.

[0046] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A wafer cleaning device for semiconductor processing, comprising a mounting frame (1), characterized in that: A storage box (2) is installed on the inner side of the mounting frame (1), and a cleaning box (3) is connected to one side of the top of the storage box (2). A transmission shaft (802) is movably connected to the inner side of the cleaning box (3) through a bearing, and a plurality of rotating wheels (803) are fixedly connected to the outer side of the transmission shaft (802). A motor for rotating the transmission shaft (802) is installed on the outer side of the cleaning box (3). A swing rod (804) is fixedly connected to one end of the transmission shaft (802), and a connecting shaft (805) is rotatably installed on the outer side of the swing rod (804). A fixed cylinder (807) is fixedly connected to the outer side of the cleaning box (3), and a movable rod (808) is slidably connected to the interior of the fixed cylinder (807). A connecting pipe (806) is connected to the outer side of the fixed cylinder (807), and a serpentine jet pipe (801) is fixedly connected to one end of the connecting pipe (806). A plurality of nozzles are arranged on the inner side of the serpentine jet pipe (801).

2. A wafer cleaning device for semiconductor processing according to claim 1, characterized in that: The top side of the storage box (2) is fixedly connected to a limit frame (602) and a mounting shell (4) in sequence; the limit frame (602) is slidably connected to a movable frame (601) inside; the mounting shell (4) is rotatably connected to a driving impeller (603) inside; the driving impeller (603) is fixedly connected to a swing shaft (604) on the outside; a filter screen (608) is detachably connected to the inside of the mounting frame body (1); two limit plates (605) are fixedly connected to the inner wall of the mounting frame body (1); the inner side of the limit plate (605) is slidably connected to a rack plate (607); the outer side of the rack plate (607) is fixedly connected to a fixed plate (609); the inner side of the fixed plate (609) is elastically connected to a scraper (610) via a plurality of springs; and a driving gear (606) is rotatably mounted on the inside of the storage box (2) via a rotating shaft.

3. A wafer cleaning device for semiconductor processing according to claim 2, characterized in that: The outer sides of the two rack plates (607) are meshedly connected with the outer side of the driving gear (606), the bottom end of the movable frame (601) is fixedly connected with the outer side of one of the limit plates (605), and the outer surface of the fixed plate (609) is in contact with the outer surface of the filter screen (608).

4. The wafer cleaning equipment for semiconductor processing according to claim 1, characterized in that: One end of the connecting shaft (805) away from the swing rod (804) is rotatably connected to one end of the movable rod (808), the outer side of the fixed cylinder (807) is connected to an air intake pipe, and the inside of the air intake pipe and the connecting pipe (806) are both installed with a one-way valve, and the conduction directions of the two one-way valves are opposite.

5. The wafer cleaning equipment for semiconductor processing according to claim 1, characterized in that: A plurality of supporting wheels (7) are installed on the inner side of the cleaning box (3), and the supporting wheels (7) are used to place wafers.

6. The wafer cleaning equipment for semiconductor processing according to claim 2, characterized in that: The outside of the installation shell (4) is connected in sequence with a first connecting pipe (501) and a second connecting pipe (502), one end of the first connecting pipe (501) is connected to the outside of the storage box (2), and the other end of the second connecting pipe (502) is connected to the outside of the cleaning box (3) through a transport component.

7. The wafer cleaning equipment for semiconductor processing according to claim 6, characterized in that: The transport component comprises a pump body, which is installed on one side of the top of the storage box (2). The output end and the input end of the pump body are both installed with pipes, one of which is connected to one side of the second connecting pipe (502), and the other pipe is fixedly connected to a liquid spray pipe (9), and the liquid spray pipe (9) is fixedly connected to the inside of the cleaning box (3).

8. A method for using a wafer cleaning device for semiconductor processing, according to the wafer cleaning device for semiconductor processing as claimed in any one of claims 1 to 7, characterized in that: The following steps are involved: Step 1: placing the semiconductor wafers to be cleaned in the grooves inside the multiple movable rods (808), and then starting the motor to drive the transmission shaft (802) to rotate, so that the multiple rotating wheels (803) rotate, and the multiple semiconductor wafers rotate synchronously; Step 2: Start the pump to transport the cleaning liquid inside the storage box (2) to the inside of the serpentine jet pipe (801) through two pipes, and spray the cleaning liquid onto the outer surfaces of the plurality of semiconductor wafers through the liquid spray pipe (9) to clean them; Step 3: As the transmission shaft (802) rotates, the swing rod (804) is driven to rotate. At this time, under the traction of the connecting shaft (805), the movable rod (808) reciprocates left and right along the inside of the fixed cylinder (807), so that the air pressure inside the fixed cylinder (807) changes continuously and generates airflow. The airflow is transported to the serpentine jet pipe (801) through the connecting pipe (806), and the airflow is sprayed onto the outer surface of the semiconductor wafer through the nozzle of the serpentine jet pipe (801), and the airflow is used to remove bubbles on the micropores of the semiconductor wafer; Step 4. When the cleaning liquid is transported to the inside of the serpentine jet pipe (801) through the pump body, the cleaning liquid will pass through the driving impeller (603) inside the mounting shell (4). The flow of water will drive the driving impeller (603) to rotate, thereby driving the swing shaft (604) to rotate synchronously. Since the end of the swing shaft (604) moves along the inside of the movable groove, the movable frame (601) reciprocates left and right along the inner wall of the limit frame (602), further driving the upper rack plate (607) to move synchronously. At this time, the lower rack plate (607) will move in the opposite direction of the upper rack plate (607) as the driving gear (606) rotates, and then the two fixed plates (609) reciprocate left and right, and the scraper (610) is used to scrape off the dirt on the outer surface of the filter screen (608).

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