High-purity silicon carbide particle ultrasonic cleaning equipment and method

Abstract

The application discloses high-purity silicon carbide particle ultrasonic cleaning equipment and method, including cleaning tank, the horizontal setting drum in the cleaning tank, the bottom of the cleaning tank is provided with ultrasonic generator;The drum is placed in the drum, and the side and bottom of the drum are evenly provided with mesh holes, the pore size of the mesh hole is smaller than the particle size of the silicon carbide particle;The ultrasonic generator is used for ultrasonic cleaning of the silicon carbide particle in the drum, the drum is driven to rotate through the drum driving system, the spray waterway is arranged in the drum, the impurities floating in the drum are migrated along the surface flow field in the direction, so that the separated graphite and dust are discharged from the drum;The graphite and fine dust attached to the surface of the silicon carbide particle are separated from the surface of the silicon carbide particle through mechanical rotation and ultrasonic cavitation effect, suspended in ultrapure water, and the spray head is continuously directional sewage discharge while overflow, so that the cleaning purpose is finally realized.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of silicon carbide particle processing, and particularly relates to a high-purity silicon carbide particle ultrasonic cleaning device and method. BACKGROUND

[0002] The statements herein merely provide background information related to the present application and do not necessarily constitute the prior art.

[0003] Silicon carbide (SiC) is a widely used third-generation semiconductor material, which has the characteristics of wide band gap, high breakdown field strength, high electron mobility, etc., and is widely used in new energy vehicles, electronic power and aerospace fields. In the silicon carbide single crystal growth process, the silicon carbide synthesis material is generally synthesized directly from silicon particles and graphite powder. After the processing process, a large amount of graphite, fine dust and other impurities will be attached to the surface of the particles. The purity of the silicon carbide synthesis material directly affects the quality and performance of the silicon carbide crystal. Therefore, it is necessary to clean the impurities attached to the surface of the silicon carbide particles under the action of ultrapure water and ultrasonic cleaning.

[0004] At present, common cleaning methods include mechanical stirring cleaning, chemical cleaning and ultrasonic cleaning, among which ultrasonic cleaning is more widely used. However, the existing technology still has the following problems:

[0005] 1. The traditional ultrasonic cleaning equipment mostly uses fixed cleaning tanks. The uneven cleaning caused by particle accumulation and the difficulty in effectively separating light floating impurities (such as graphite) and sedimentary impurities result in low cleaning efficiency.

[0006] 2. The existing equipment lacks an optimized cleaning mode for different impurities. The ultrasonic frequency is fixed and cannot adapt to the differentiated cleaning needs of graphite (which requires low frequency) and fine dust (which requires high frequency). At the same time, floating impurities are prone to stay on the liquid surface, and there is a lack of effective surface stripping and directional discharge mechanism. In addition, the silicon carbide particles are prone to loss with the drainage during the cleaning process. The existing equipment mostly does not set up an efficient recovery structure, resulting in waste of raw materials.

[0007] 3. Some equipment uses metal materials or non-inert materials, which may introduce metal ions or organic matter pollution under the action of strong ultrasonic, affecting the purity of silicon carbide. At the same time, the excessive intervention of artificial will cause secondary pollution, which is not suitable for batch production. SUMMARY

[0008] The purpose of the present application is to provide a high-purity silicon carbide particle ultrasonic cleaning device and method, which can realize efficient cleaning of silicon carbide particles.

[0009] In order to achieve the above purpose, the present application is realized by the following technical scheme:

[0010] In a first aspect, embodiments of the present application provide a high-purity silicon carbide particle ultrasonic cleaning device, comprising a cleaning tank, a roller horizontally arranged in the cleaning tank, and an ultrasonic generator arranged at the bottom of the cleaning tank; the roller is arranged with silicon carbide particles to be cleaned, and the side and bottom surfaces of the roller are uniformly provided with mesh holes, the mesh hole diameter being smaller than the particle size of the silicon carbide particles; the ultrasonic generator performs ultrasonic cleaning on the silicon carbide particles in the roller, the roller is driven to rotate by a roller driving system, a spraying waterway is arranged in the roller, and the impurities floating in the roller are orientedly migrated with the surface flow field to discharge the separated graphite and dust out of the roller.

[0011] As a further technical solution, the roller driving system comprises a right-angle gear reduction motor, a driving gear, and gear driven rollers, the output shaft of the right-angle gear reduction motor is fixedly connected with the driving gear, the driving gear is engaged with the gears on the gear driven rollers, and the gear driven rollers are symmetrically arranged above and below.

[0012] As a further technical solution, the roller is located between the two gear driven rollers, each gear driven roller is provided with two O-rings, and the roller is provided with two annular raceways at positions corresponding to the four O-rings on both sides, the O-rings are located in the annular raceways, and the roller is driven to rotate by the friction between the O-rings and the annular raceways.

[0013] As a further technical solution, the spraying waterway is driven by a push-pull spraying system, the push-pull spraying system comprises two push-pull cylinders, a spraying waterway, and a roller cover, the output end of the first push-pull cylinder is fixedly connected with the spraying waterway to drive the spraying waterway to move, the spraying waterway enters the roller through the center hole of the roller cover to spray, and the output end of the second push-pull cylinder is connected with the roller cover to drive the roller cover to move horizontally and open and close the roller.

[0014] As a further technical solution, one end of the spraying waterway is connected with an ultrapure water hose, the other end is connected with a fan-shaped spraying head, and the fan-shaped spraying head is arranged in the roller.

[0015] As a further technical solution, the maximum height of the silicon carbide particles to be cleaned arranged in the roller is lower than the lowest part of the roller cover, and the fan-shaped spraying head is higher than the overflow water surface of the cleaning tank.

[0016] As a further technical solution, the bottom of the cleaning tank is provided with a water inlet and a drain, and the water inlet is connected with an ultrapure water pipeline.

[0017] As a further technical solution, the upper edge of the cleaning tank is serrated.

[0018] As a further technical solution, the roller driving system, the roller, and the push-pull spraying system are all made of pp material.

[0019] In a second aspect, embodiments of the present application provide a high-purity silicon carbide particle ultrasonic cleaning method, using the high-purity silicon carbide particle ultrasonic cleaning equipment of the first aspect, comprising the following steps:

[0020] The silicon carbide particles to be cleaned are placed in the drum through the opening at the end of the drum, and the opening end of the drum is closed by the drum cover;

[0021] The drum driving system and the ultrasonic generator are started, and under the synergistic action of the rotation of the drum and the ultrasonic cavitation generated by the ultrasonic generator, the graphite and fine dust attached to the surface of the silicon carbide particles are separated; during the cleaning process, pure water continuously overflows, and at the same time, the spray waterway continuously sprays the water surface to discharge the separated graphite and fine dust out of the drum.

[0022] The beneficial effects of the above embodiments of the present application are as follows:

[0023] (1) The high-purity silicon carbide particle ultrasonic cleaning equipment in the present application separates the graphite and fine dust attached to the surface of the silicon carbide particles through the rotation of the drum and ultrasonic cavitation. The bottom of the cleaning tank is provided with a water inlet, and pure water continuously overflows while ultrasonic and tumbling; the side surface and the bottom surface of the drum are provided with mesh holes, which are conducive to the discharge of impurities from the drum; the drum rotates 360° and the speed is adjustable, and can be set to rotate alternately in forward and reverse directions, and the ultrasonic generator can output a sweep frequency of 40 kHz-120 kHz for different impurities. The fan-shaped spray head of the spray waterway sprays fan-shaped water flow to the water surface at an inclination angle of 30°, so that the floating impurities migrate directionally with the surface flow field. The overall material of the equipment is PP material, which avoids secondary pollution, has high cleaning efficiency, and realizes a high degree of automatic cleaning.

[0024] (2) The drum driving system in the present application is provided with a flexible coupling structure of O-ring and annular raceway, the O-ring (fluorine rubber) of the gear driven roller is embedded in the annular raceway of the drum, the power is transmitted through friction, the impact load of the PP gear is buffered, and the tooth breakage caused by traditional rigid engagement is avoided. The push-pull spray system realizes dynamic drum sealing, the drum cover is sealed by the cylinder, the spray waterway penetrates the center of the cover body, the fan-shaped spray head (30° inclination angle) reciprocates in the drum to spray, forming a directional water flow to push the impurities to migrate to the overflow port, and there is no manual intervention throughout the process.

[0025] (3) The sawtooth structure on the upper edge of the cleaning tank breaks the water surface tension, so that the floating graphite is preferentially discharged with overflow; the spray system sprays ultrapure water at an inclination angle of 30° to form a surface tangential flow field, which is conducive to the discharge of impurities from the drum; the double waterway design at the bottom of the cleaning tank (ultrapure water is continuously injected through the water inlet, and sewage is automatically discharged through the drain) forms dynamic updating, and realizes the closed loop of "zero particle loss and complete impurity discharge" in combination with the mesh holes of the drum. BRIEF DESCRIPTION OF DRAWINGS

[0026] The accompanying drawings, which form a part of this specification, are included to provide a further understanding of the application, and are incorporated into and constitute a part of this specification. The embodiments of the application, and their

[0027] Figure 1 is a schematic diagram of the overall structure of the high-purity silicon carbide particle ultrasonic cleaning equipment of the present application;

[0028] Figure 2 is a front view of the internal structure of the high-purity silicon carbide particle ultrasonic cleaning equipment of the present application;

[0029] Figure 3 is a top view of the roller drive system of the present application;

[0030] Figure 4 is a top view of the roller cover and the spray waterway of the present application;

[0031] Figure 5 is a schematic diagram of the structure of the roller and the roller cover of the present application;

[0032] Figure 6 is a bottom view of the roller of the present application;

[0033] Figure 7 is a side view of the roller of the present application;

[0034] Figure 8 is a schematic diagram of the maximum material height in the roller of the present application.

[0035] The schematic diagram is only for illustration;

[0036] wherein 1 is a bevel gear reduction motor; 2 is a drive gear; 3 is a gear driven roller; 4 is an O-ring; 5 is a first push-pull cylinder; 6 is a second push-pull cylinder; 7 is a spray waterway; 8 is a fan-shaped spray head; 9 is a roller cover; 10 is a roller cover support rod; 11 is a roller; 12 is a cleaning tank; 13 is a water inlet; 14 is a water outlet; 15 is an ultrasonic generator; and 16 is an annular raceway. DETAILED DESCRIPTION

[0037] It should be noted that the following detailed description is merely exemplary and is intended to provide further description of the application. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

[0038] Example 1

[0039] In a typical embodiment of the present application, as Figures 1 to 8As shown, a high-purity silicon carbide particle ultrasonic cleaning device is provided, which comprises a cleaning tank 12, a roller 11 horizontally arranged in the cleaning tank 12, and an ultrasonic generator 15 arranged at the bottom of the cleaning tank 12; the roller 11 is used to place the silicon carbide particles to be cleaned, and the side and bottom surfaces of the roller 11 are uniformly provided with mesh holes, the aperture of the mesh holes is smaller than the particle size of the silicon carbide particles; the ultrasonic generator 15 performs ultrasonic cleaning on the silicon carbide particles in the roller 11, the roller 11 is driven to rotate by a roller driving system, a spraying waterway 7 is arranged in the roller 11, and the impurities floating in the roller are oriented to migrate along the surface flow field to discharge the separated graphite and dust out of the roller.

[0040] In the process of cleaning the silicon carbide particles, the above device continuously rotates the roller (rather than static soaking), fully turns the silicon carbide particles, completely avoids the cleaning dead angle caused by particle accumulation, and significantly improves the cleaning uniformity. Figure 6 And Figure 7 As shown, by arranging appropriate mesh holes on the side and bottom surfaces of the roller, the particles are prevented from being lost, the micron-level graphite and dust stripped are allowed to be discharged from the mesh holes, and selective separation of impurities is realized; in the cleaning process, the ultrasonic cavitation effect deeply strips the attachments on the surface of the silicon carbide, and the dynamic water flow formed by the directional spraying in the roller pushes the light impurities to migrate to the overflow port, which solves the problem that the traditional equipment cannot simultaneously remove the sedimentary impurities and floating graphite, and effectively improves the cleaning efficiency.

[0041] As shown, Figure 3 The roller driving system comprises a right-angle gear reduction motor 1, a driving gear 2, and gear driven rollers 3, the output shaft of the right-angle gear reduction motor 1 is fixedly connected with the driving gear 2, the driving gear 2 is engaged with the gears on the gear driven rollers 3, and the gear driven rollers 3 are arranged symmetrically above and below.

[0042] Further, the roller is located between the two gear driven rollers 3, each gear driven roller 3 is provided with two O-rings 4, the two sides of the roller are provided with two annular raceways 16 at positions corresponding to the four O-rings 4, the O-rings 4 are located in the annular raceways 16, and the roller is driven to rotate by the friction force between the O-rings 4 and the annular raceways 16.

[0043] When the device is working, the power is transmitted to the drive gear 2 through the right-angle gear deceleration motor 1, so as to rotate the two gear driven rollers 3, the roller 11 is placed between the two gear driven rollers 3, the O-ring 4 on the gear driven roller 3 is placed in the annular raceway 16 on the roller, and the roller is driven to rotate by the friction force between the O-ring 4 and the annular raceway 16. Since the whole device is made of PP material, if rigid transmission is adopted between the gear driven roller 3 and the roller, it is easy to cause wear and breakage, and such transmission design can realize flexible transmission of power and improve fault tolerance of power transmission.

[0044] The traditional direct meshing of the gear and the PP roller is easy to cause gear breakage, in the embodiment, the power is transmitted through the friction force between the O-ring 4 and the annular raceway 16 of the roller by the four-stage transmission of the drive gear 2→gear driven roller 3→O-ring 4→roller. It has the following advantages: the O-ring 4 (such as fluorine rubber) elastically deforms to absorb impact, avoiding PP gear burst caused by rigid contact; the symmetrical layout of the double gear driven rollers 3 and the four O-rings 4 ensures that the roller is balanced in force and the rotational speed is stable; the annular raceway 16 restricts the radial displacement of the O-ring 4, eliminates slip, and strengthens the particle tumbling effect.

[0045] As shown in Figure 4 , the push-pull spray system includes two push-pull cylinders, a spray waterway 7 and a roller cover 9; the output end of the first push-pull cylinder 5 is fixed with the spray waterway 7 to drive the spray waterway 7 to move, the spray waterway 7 passes through the center hole of the roller cover 9 to enter the roller to spray; the output end of the second push-pull cylinder 6 is connected with the roller cover 9 through a roller cover support rod 10 to drive the roller cover 9 to move horizontally and open and close the roller.

[0046] Further, one end of the spray waterway 7 is connected with an ultrapure water hose, and the other end is connected with a fan-shaped spray head 8, and the fan-shaped spray head 8 is arranged in the roller.

[0047] The push-pull spray system of the embodiment can send the fan-shaped spray head 8 into the roller or move the fan-shaped spray head 8 out of the roller by driving the spray waterway 7 to move horizontally by the first push-pull cylinder. Figure 5 As shown in , the roller cover 9 is driven by the second push-pull cylinder 6 to move horizontally to open and close the roller, the roller cover 9 closes the roller when the roller rotates to prevent silicon carbide particles from falling out of the roller, and the roller cover 9 is opened to take out the cleaned silicon carbide particles from the roller after the cleaning is completed.

[0048] As shown in Figure 8 , the maximum height of the silicon carbide particles to be cleaned placed in the roller is lower than the lowest part of the roller cover 9. Since the roller rotates at a low speed, the material is lifted to a certain height and naturally falls back, and the roller cover 9 is well attached to the roller and does not have friction, so that the material is prevented from escaping. Figure 2As shown, when the drum is placed in the cleaning tank 12, the height of the drum is higher than the height of the cleaning tank 12, as long as the maximum height of the material is lower than the upper edge of the cleaning tank 12, and the height of the fan-shaped spray head is slightly higher than the overflow water surface. The spray waterway 7 reciprocates during spraying, which is beneficial to push out impurities.

[0049] In this embodiment, the bottom of the cleaning tank 12 is provided with a water inlet 13 and a drain, the water inlet 13 is connected with an ultrapure water pipeline, and ultrapure water is input into the cleaning tank 12 through the water inlet 13. After the material cleaning is completed, the water in the cleaning tank 12 is discharged through the drain.

[0050] In this embodiment, the upper edge of the cleaning tank 12 is serrated, which is beneficial to overflow and discharge the impurities floating on the water surface.

[0051] In this embodiment, the drum driving system, the drum, and the push-pull spray system are all made of pp material, which is not easy to cause secondary pollution.

[0052] The working principle of the high-purity silicon carbide particle ultrasonic cleaning equipment provided in this embodiment is as follows:

[0053] The silicon carbide particles are placed in the drum, and the maximum material height is as shown in the figure. Figure 8 As shown, the second push-pull cylinder 6 is controlled to close the drum cover 9 through the operation panel, ultrapure water enters from the water inlet 13 of the cleaning tank 12, and the water inlet is stopped when the cleaning tank 12 is full of water. At this time, the water level is flush with the upper edge of the cleaning tank 12 and exceeds the material. The ultrasonic generator and the right-angle gear reducer motor 1 are turned on, the first push-pull cylinder 5 is opened to control the reciprocating motion of the spray waterway 7, and the fan-shaped spray head 8 starts to spray. The silicon carbide particles are ultrasonically and tumbled in the drum, the graphite and fine dust attached to the surface of the silicon carbide particles are separated through the rotation of the drum and the ultrasonic cavitation effect, the attached graphite and fine dust float on the water surface, the pure water in the cleaning tank 12 continuously overflows, and the floating impurities are oriented migrated with the surface flow field, which is convenient for the impurities to be discharged from the side and bottom of the drum, so as to reduce the impurities and achieve the purpose of continuous cleaning.

[0054] The high-purity silicon carbide particle ultrasonic cleaning equipment provided in this embodiment is made of pp material, which can avoid secondary pollution. The equipment realizes the cooperation of mechanical tumbling and ultrasonic waves, and also has the functions of spraying and sewage discharge. It not only has high cleaning efficiency, but also realizes high degree of automatic cleaning.

[0055] Embodiment 2

[0056] In a typical embodiment of the present application, a high-purity silicon carbide particle ultrasonic cleaning method is provided, which comprises the following steps:

[0057] The silicon carbide particles to be cleaned are placed in the drum from the end opening of the drum, and the open end of the drum is closed by the drum cover;

[0058] The drum driving system and the ultrasonic generator are started, and under the synergistic action of the rotation of the drum and the ultrasonic cavitation generated by the ultrasonic generator, the graphite and fine dust attached to the surface of the silicon carbide particles are separated; during the cleaning process, the pure water continuously overflows, and at the same time, the water surface is continuously sprayed by the spray waterway, so as to discharge the separated graphite and fine dust out of the drum.

[0059] The above only describes the preferred embodiments of the present application and is not used to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An ultrasonic cleaning device for high-purity silicon carbide particles, characterized in that, The device includes a cleaning tank, in which a horizontally arranged roller is installed, and an ultrasonic generator is installed at the bottom of the cleaning tank. Silicon carbide particles to be cleaned are placed inside the roller, and the sides and bottom of the roller are uniformly perforated with mesh holes, the aperture of which is smaller than the particle size of the silicon carbide. The ultrasonic generator performs ultrasonic cleaning on the silicon carbide particles inside the roller. The roller is driven to rotate by a roller drive system, and a spray water path is provided inside the roller. The spray water path causes impurities floating inside the roller to migrate directionally with the surface flow field, thereby discharging detached graphite and dust from the roller. The roller drive system includes a right-angle gear reducer motor, a drive gear, and a gear driven roller. The output shaft of the right-angle gear reducer motor is fixedly connected to the drive gear. The drive gear meshes with a gear on the gear driven roller. There are two gear driven rollers, which are arranged symmetrically up and down. The roller is located between two gear driven rollers. Each gear driven roller is provided with two O-rings. Two annular raceways are provided on both sides of the roller at positions corresponding to the four O-rings. The O-rings are located inside the annular raceways. The roller is driven to rotate by the friction between the O-rings and the annular raceways. The spray water path is driven by a push-pull spray system, which includes two push-pull cylinders, a spray water path, and a drum cover. The output end of the first push-pull cylinder is fixed to the spray water path, driving the spray water path to move. The spray water path passes through the center hole of the drum cover and enters the drum for spraying. The output end of the second push-pull cylinder is connected to the drum cover, driving the drum cover to move horizontally, thereby opening and closing the drum. One end of the spray water path is connected to an ultrapure water hose, and the other end is connected to a fan-shaped spray head, which is placed inside the drum.

2. The ultrasonic cleaning equipment for high-purity silicon carbide particles as described in claim 1, characterized in that, The maximum height of the silicon carbide particles to be cleaned placed inside the drum is lower than the lowest point of the drum cover, and the fan-shaped spray head is higher than the overflow water surface of the cleaning tank.

3. The ultrasonic cleaning equipment for high-purity silicon carbide particles as described in claim 1, characterized in that, The bottom of the cleaning tank is provided with a water inlet and a water outlet, and the water inlet is connected to an ultrapure water pipeline.

4. The ultrasonic cleaning equipment for high-purity silicon carbide particles as described in claim 1, characterized in that, The upper edge of the cleaning tank is serrated.

5. The ultrasonic cleaning equipment for high-purity silicon carbide particles as described in claim 1, characterized in that, The roller drive system, roller, and push-pull spray system are all made of PP material.

6. A method for ultrasonic cleaning of high-purity silicon carbide particles, using the ultrasonic cleaning equipment for high-purity silicon carbide particles as described in any one of claims 1-5, characterized in that, Includes the following steps: The silicon carbide particles to be cleaned are placed inside the drum through the end opening, and the opening end of the drum is sealed by the drum cover. The drum drive system and ultrasonic generator are started. Under the combined effect of the drum rotation and the ultrasonic cavitation generated by the ultrasonic generator, the graphite and fine dust attached to the surface of the silicon carbide particles are removed. During the cleaning process, pure water overflows continuously, and at the same time, the spray water channel sprays water onto the water surface to discharge the removed graphite and fine dust from the drum.

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