Device for processing nano-powder through microwave plasma

Abstract

The invention provides a device for processing nano-powder through microwave plasma. The device comprises a nano-powder feeder, an ultrasonic generator, a microwave plasma generator and a gas distributor. An air inlet hole and a material passing hole are formed in the air distributor, one end of the material passing hole is communicated with the discharging port, the other end of the material passing hole is communicated with the plasma reaction cavity, and a plurality of air passing holes used for communicating the air inlet hole with the plasma reaction cavity are formed in the positions, corresponding to the periphery of the material passing hole, in the air distributor and are uniformly formed in the circumferential direction of the material passing hole; and therefore, gas entering from the gas inlet hole can enter the plasma reaction cavity after being uniformly dispersed through the gas holes and spirally flow. According to the device for processing the nano-powder through the microwave plasma, the microwave plasma is more uniform and stable, the processed nano-powder absorbs microwave energy more uniformly, the sphericity degree of the powder is better, the spheroidization rate is higher, and the quality and efficiency are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of powder processing, and particularly relates to a device for treating nano-powders by microwave plasma. Background Art

[0002] In recent years, semiconductor technology has developed rapidly. The feature size of chips has been continuously reduced and the integration degree has been improved, which puts forward higher requirements for the flatness of the polished surface. The importance of preparing polishing abrasives has become increasingly prominent. At present, polishing abrasives are mainly inorganic oxide nanoparticles, such as cerium oxide, silicon oxide, aluminum oxide, and zirconium oxide, which achieve the polishing effect by means of mechanical friction, adsorption, and removal of corrosion products. However, existing preparation processes such as chemical reaction methods and physical mechanical grinding methods have many problems. Not only are the processes simple and rough, generating a large amount of waste gas and wastewater, but also the particle size distribution of the products is relatively wide, making it difficult to meet the requirements of high-precision polishing.

[0003] As an emerging preparation method, microwave plasma technology can obtain powders with higher sphericity by melting and remelting the surface of powders at high temperature, or prepare nano-nonmetal powders through chemical reactions, showing unique advantages. However, there are also technical problems. Nano-powders are small in size and are prone to clogging the pipeline when feeding powder at the powder feeding port, resulting in poor powder feeding and affecting production continuity and product quality. At the same time, when the powder melts in the reaction chamber (usually a quartz tube), the expanded and melted powder is easily adhered to the inner wall of the quartz tube, causing the quartz tube to rupture, shortening its service life, and increasing production costs.

[0004] More critically, the powder adhered to the inner wall of the reaction chamber will also have a reflection effect on microwave transmission, reducing the energy density of microwave plasma, and then reducing the sphericity rate, making it impossible to achieve continuous and stable production, seriously restricting the large-scale application of this technology. Therefore, it is necessary to propose an innovative solution to adjust the existing process to solve these problems, promote the development of semiconductor polishing technology, and meet the requirements of the semiconductor industry for high-precision polishing. Summary of the Invention

[0005] In view of this, the present invention aims to provide a device for treating nano-powders by microwave plasma to solve the problem that the powder adhered to the inner wall of the reaction chamber affects the sphericity rate when treating nano-powders by microwave plasma in the prior art.

[0006] To achieve the above object, the technical solution of the present invention is realized as follows:

[0007] A device for treating nano-powders by microwave plasma includes a nano-powder feeder, an ultrasonic generator, a microwave plasma generator, and a gas distributor;

[0008] The nano-powder feeder includes a powder bin for storing the powder material to be treated;

[0009] The ultrasonic generator is arranged at the discharge port of the powder bin to drive the powder material to be processed in the powder bin to be discharged from the discharge port;

[0010] The microwave plasma generator is provided with a plasma reaction chamber. One end of the microwave plasma generator is connected to the discharge port of the powder bin through a gas distributor, and the other end is provided with a discharge port communicating with the plasma reaction chamber;

[0011] The gas distributor is provided with an air inlet hole and a material passing hole. One end of the material passing hole communicates with the discharge port, and the other end communicates with the plasma reaction chamber. Around the material passing hole in the gas distributor, there are air passing holes for communicating the air inlet hole and the plasma reaction chamber. A plurality of air passing holes are evenly arranged along the circumferential direction of the material passing hole, so that the gas entering from the air inlet hole can enter the plasma reaction chamber after being evenly dispersed through the air passing holes and flow in a spiral shape.

[0012] Further, the gas distributor includes an air inlet adapter and a gas distributing member. The air inlet hole is arranged on one side of the air inlet adapter, and there is a flow chamber communicating with the air inlet hole between the air inlet adapter and the gas distributing member; the material passing hole and the air passing holes are both arranged on the gas distributing member. Each air passing hole is obliquely arranged on the gas distributing member. One end of each air passing hole obliquely upward communicates with the flow chamber, and the other end communicates with the plasma reaction chamber.

[0013] Further, the air inlet adapter is detachably installed on the microwave plasma generator, and the air inlet adapter is provided with an assembly groove for cooperating with the gas distributing member.

[0014] Further, the microwave plasma generator includes a waveguide and a quartz tube arranged on the waveguide. The quartz tube is coaxially arranged with the material passing hole, and the plasma reaction chamber is arranged in the quartz tube. A water-cooling auxiliary device is also arranged on the waveguide corresponding to the position of the quartz tube.

[0015] Further, the quartz tube is detachably installed on the waveguide, and the waveguide is provided with an inner ferrule for cooperating with the quartz tube.

[0016] Further, a gas distributing adapter for connecting the air inlet adapter is also arranged on the waveguide corresponding to the position of the quartz tube. One end of the gas distributing adapter is provided with an assembly hole for cooperating with the gas distributing member, and the other end is provided with a positioning groove for cooperating with the end of the quartz tube. The assembly hole communicates with the positioning groove.

[0017] Further, a first sealing member for cooperating with the quartz tube is arranged on the gas distributing adapter corresponding to the position of the positioning groove, and a second sealing member for cooperating with the air inlet adapter is arranged on the gas distributing adapter corresponding to the position of the assembly hole.

[0018] Further, an ultrasonic fixing ring for connecting an ultrasonic generator is provided at a position corresponding to the lower part of the powder outlet on the powder bin. One end of the ultrasonic fixing ring is communicated with the powder outlet of the powder bin, and the other end is communicated with the material passing hole of the air distributor. A screen is arranged in the ultrasonic fixing ring.

[0019] Further, a detachable adapter pipe is provided on the air inlet adapter. The adapter pipe is detachably connected to the ultrasonic fixing ring. Sealing rings are provided between the adapter pipe and the ultrasonic fixing ring and between the adapter pipe and the air inlet adapter. One end of the adapter pipe extending into the ultrasonic fixing ring is provided with a flared feed inlet, and the other end extends into the material passing hole and is communicated with the plasma reaction chamber.

[0020] Further, an openable and closable cover is provided above the powder bin, and a control switch for controlling the on-off of the powder outlet is provided at a position corresponding to the powder outlet below the powder bin. A protective gas inlet is provided on the cover.

[0021] Compared with the prior art, the device for treating nano-powders by microwave plasma of the present invention has the following advantages:

[0022] The device for treating nano-powders by microwave plasma of the present invention realizes more uniform and stable microwave plasma. The nano-powders treated absorb microwave energy more uniformly, have better powder sphericity and higher spheroidization rate, improving the quality and efficiency. By adopting the ultrasonic vibration method, the problem of nano-powder transportation is solved, which can ensure uniform transportation of nano-powders, thus being beneficial to improving the treatment effect. In addition, by adopting an air distributor, the plasma gas around the nano-powders during treatment is more uniform, the generated plasma is more stable, and the heat absorbed by the nano-powders is more uniform, further improving the treatment effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The drawings forming a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings:

[0024] Figure 1 is a schematic structural diagram of the device for treating nano-powders by microwave plasma according to an embodiment of the present invention;

[0025] Figure 2 is a schematic structural diagram of the nano-powder feeder in the device for treating nano-powders by microwave plasma according to an embodiment of the present invention;

[0026] Figure 3 is Figure 2 a cross-sectional view of;

[0027] Figure 4Schematic structural diagram of the ultrasonic generator in the device for treating nano-powders by microwave plasma according to an embodiment of the present invention;

[0028] Figure 5 Schematic structural diagram of the air inlet adapter in the device for treating nano-powders by microwave plasma according to an embodiment of the present invention;

[0029] Figure 6 is Figure 5 cross-sectional view of;

[0030] Figure 7 Schematic structural diagram of the gas distributor in the device for treating nano-powders by microwave plasma according to an embodiment of the present invention;

[0031] Figure 8 is Figure 7 cross-sectional view of;

[0032] Figure 9 Schematic structural diagram of the microwave plasma generator in the device for treating nano-powders by microwave plasma according to an embodiment of the present invention;

[0033] Figure 10 is Figure 9 cross-sectional view of.

[0034] Explanation of reference numerals:

[0035] 100, nano-powder feeder; 110, powder bin; 120, bin cover; 121, protective gas inlet; 130, control switch; 140, ultrasonic fixing ring; 150, adapter pipe; 200, ultrasonic generator; 210, ultrasonic vibrating rod; 220, vibration clamp; 300, gas distributor; 310, air inlet adapter; 311, air inlet hole; 320, gas distributor part; 321, gas passing hole; 322, material passing hole; 400, microwave plasma generator; 410, waveguide; 411, upper water inlet; 412, upper water outlet; 420, gas distribution adapter; 430, snap ring; 440, inner bushing; 450, water-cooling auxiliary device; 451, lower water inlet; 452, lower water outlet; 460, sealing bushing; 470, quartz tube. Detailed implementation manners

[0036] The present invention will be further described in detail below with reference to the drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the present invention, rather than limiting the present invention. Additionally, it should be noted that for the sake of description, only parts related to the present invention are shown in the drawings rather than all structures.

[0037] A device for treating nano-powders by microwave plasma, as Figures 1 to 10As shown, it includes a nano-powder feeder 100, an ultrasonic generator 200, a microwave plasma generator 400, and a gas distributor 300.

[0038] The above-mentioned nano-powder feeder 100 includes a powder bin 110 for storing powder materials to be processed. Specifically, an openable and closable bin cover 120 is provided above the powder bin 110, and a control switch 130 for controlling the on / off of the discharge port is provided at a position corresponding to the discharge port below the powder bin 110. A protective gas inlet 121 is provided on the bin cover 120. Exemplarily, the bin cover 120 can be detachably installed on the powder bin 110 by conventional means such as screw connection, and the control switch 130 can be a conventional switch such as a stop valve. By providing the openable and closable bin cover 120, it is convenient to add powder materials, and by providing the control switch 130, the opening and closing of the discharge port and the discharge amount of the powder materials can be controlled. In addition, by providing the protective gas inlet 121 on the bin cover 120, it is convenient to connect to an external protective gas supply device.

[0039] The above-mentioned ultrasonic generator 200 is provided at the discharge port of the powder bin 110 to drive the powder materials to be processed in the powder bin 110 to be discharged from the discharge port.

[0040] The above-mentioned microwave plasma generator 400 is provided with a plasma reaction chamber. One end of the microwave plasma generator 400 is connected to the discharge port of the powder bin 110 through the gas distributor 300, and the other end is provided with a discharge port communicating with the plasma reaction chamber.

[0041] The above-mentioned gas distributor 300 is provided with an air inlet hole 311 and a material passing hole 322. One end of the material passing hole 322 is communicated with the discharge port, and the other end is communicated with the plasma reaction chamber. A gas passing hole 321 for communicating the air inlet hole 311 and the plasma reaction chamber is provided at a position corresponding to the periphery of the material passing hole 322 in the gas distributor 300. A plurality of gas passing holes 321 are uniformly arranged along the circumferential direction of the material passing hole 322, so that the gas entering from the air inlet hole 311 can enter the plasma reaction chamber after being uniformly dispersed through the gas passing holes 321 and flow in a spiral shape.

[0042] Specifically, the air inlet hole 311 can be connected to an external gas supply device to realize the supply of protective gas. Among them, the protective gas not only protects the powder in a suitable atmosphere environment, but also has a certain pressure to promote the powder to flow into the plasma reaction chamber.

[0043] Preferably, the gas distributor 300 includes an intake adapter 310 and a gas distribution member 320. The intake hole 311 is provided on one side of the intake adapter 310, and there is a flow chamber communicating with the intake hole 311 between the intake adapter 310 and the gas distribution member 320. The material passing holes 322 and the air passing holes 321 are both provided on the gas distribution member 320. Each air passing hole 321 is inclined on the gas distribution member 320. One end of each air passing hole 321 inclined upward is communicated with the flow chamber, and the other end is communicated with the plasma reaction chamber.

[0044] Exemplarily, the intake hole 311 is provided on one side of the intake adapter 310 and is offset from the axis of the material passing hole 322, so that the air flow entering the flow chamber through the intake hole 311 can first perform a spiral flow. At the same time, the air passing hole 321 can be inclined at an angle θ, where θ is an acute angle. The diameter ratio of the air passing hole 321 to the material passing hole 322 is between 1 and 20. Those skilled in the art can select a suitable ratio according to actual needs to ensure that the gas entering through the intake hole 311 can be evenly dispersed through the air passing hole 321 and enter the plasma reaction chamber in a spiral shape.

[0045] During actual application, the protective gas flowing along the air passing hole 321 will form a uniformly flowing downward spiral gas. Therefore, by evenly arranging the inclined air passing holes 321 around the material passing hole 322, the gas entering the air passing hole 321 through the flow chamber can flow into the plasma reaction chamber under the guidance of the air passing hole 321 and finally form a spiral air flow flowing downward. On the one hand, a certain negative pressure will be formed at the axis under the drive of the air flow, and the powder falling through the axis of the material passing hole 322 will be dispersed downward and around. On the other hand, the air flow can also prevent the inner wall of the quartz tube 470 from being adhered by the powder and make the plasma gas more uniform, so that the generated microwave plasma is more uniform and stable. At this time, the powder melts in the uniform and stable plasma, and the stable downward rotation movement is not easy to adhere to the inner wall of the quartz tube 470, and the processing efficiency will be higher.

[0046] Preferably, the intake adapter 310 is detachably installed on the microwave plasma generator 400, and the intake adapter 310 is provided with an assembly groove for cooperating with the gas distribution member 320. Specifically, the microwave plasma generator 400 includes a waveguide 410 and a quartz tube 470 provided on the waveguide 410. The quartz tube 470 is coaxially arranged with the material passing hole 322, and the plasma reaction chamber is arranged inside the quartz tube 470. A water-cooling auxiliary device 450 is also provided on the waveguide 410 at the position corresponding to the quartz tube 470.

[0047] Preferably, the quartz tube 470 is detachably mounted on the waveguide 410, and an inner ferrule 440 cooperating with the quartz tube 470 is provided on the waveguide 410. Exemplarily, a positioning portion is provided at one end of the quartz tube 470 extending out of the inner ferrule 440, and a sealing ferrule 460 capable of cooperating with the positioning portion is provided on the inner ferrule 440. The sealing ferrule 460 is detachably mounted on the inner ferrule 440, and a card slot cooperating with the positioning portion is provided on the sealing ferrule 460. Among them, the inner ferrule 440 is fixed on the waveguide 410, and the sealing ferrule 460 can be mounted on the inner ferrule 440 by conventional means such as screws. By adopting a detachable method to mount the quartz tube 470, it is convenient for the assembly and maintenance of the quartz tube 470, reducing the difficulty of use and maintenance of this device. Those skilled in the art can also select other suitable detachable methods to mount the quartz tube 470 and the inner ferrule 440 according to actual needs, which will not be elaborated here.

[0048] In the actual application process, the water-cooling auxiliary device 450 can be fixed below the waveguide 410. Cooling cavities are provided both in the water-cooling auxiliary device 450 and the waveguide 410. A lower water inlet 451 and a lower water outlet 452 communicating with the internal cooling cavity of the water-cooling auxiliary device 450 are provided on the water-cooling auxiliary device 450, and an upper water inlet 411 and an upper water outlet 412 communicating with the internal cooling cavity of the waveguide 410 are provided on the waveguide 410. In addition, sealing structures such as sealing rings can also be provided between the water-cooling auxiliary device 450 and the waveguide 410, and between the water-cooling auxiliary device 450 and the inner ferrule 440. During actual use, by supplying coolant to the cooling cavities in the water-cooling auxiliary device 450 and the waveguide 410, the temperatures of the waveguide 410 and the quartz tube 470 can be reduced to avoid damage to the sealing structures at various parts of the waveguide 410 and the quartz tube 470.

[0049] Preferably, a gas distribution adapter 420 for connecting the intake adapter 310 is further provided at the position of the waveguide 410 corresponding to the quartz tube 470. One end of the gas distribution adapter 420 is provided with an assembly hole cooperating with the gas distribution member 320, and the other end is provided with a positioning groove cooperating with the end of the quartz tube 470. The assembly hole communicates with the positioning groove.

[0050] Exemplarily, a snap ring 430 cooperating with the quartz tube 470 is provided above the waveguide 410. The snap ring 430 can be fixed on the waveguide 410 by conventional installation such as screws, and the gas distribution adapter 420 can also be fixed on the snap ring 430 by conventional installation such as screws. In addition, the intake adapter 310 can also be fixed on the gas distribution adapter 420 by conventional means such as screws.

[0051] In the actual application process, the gas distributor 320 is a circular ring-shaped structural part. The outer diameter of the quartz tube 470 is greater than the diameter of the gas distributor 320, and the inner diameter is less than the diameter of the gas distributor 320. By setting a positioning groove on the gas distribution adapter 420, a good limiting effect can be achieved on the end of the quartz tube 470. At the same time, in cooperation with the pressing and fitting of the gas distributor 320 and the end of the quartz tube 470, it can ensure that the gas in the flow cavity can uniformly disperse through the gas passing holes 321 and then flow into the quartz tube 470.

[0052] Preferably, a first seal member cooperating with the quartz tube 470 is provided at the position corresponding to the positioning groove on the gas distribution adapter 420, and a second seal member cooperating with the intake adapter 310 is provided at the position corresponding to the assembly hole on the gas distribution adapter 420. Exemplarily, both the first seal member and the second seal member can adopt existing sealing rings. Those skilled in the art can select appropriate numbers and models of sealing rings for setting according to actual needs, which will not be elaborated here. By setting the first seal member and the second seal member, the sealing performance of the device gas path can be ensured, preventing gas leakage.

[0053] Specifically, when the microwave plasma generator 400 operates, the plasma gas reaches the plasma reaction cavity in the quartz tube 470 through the gas distribution adapter 420, absorbs the microwave transmitted by the waveguide 410 to generate microwave plasma, and forms a stable plasma high-temperature zone in the quartz tube 470. When the nano powder falls from the material passing hole 322 and passes through the high-temperature zone, remelting and solidification occur to realize the spheroidization of the powder.

[0054] Preferably, an ultrasonic fixing ring 140 for connecting the ultrasonic generator 200 is provided at the position corresponding to the lower part of the discharge port on the powder bin 110. One end of the ultrasonic fixing ring 140 is communicated with the discharge port of the powder bin 110, and the other end is communicated with the material passing hole 322 of the gas distributor 300. A sieve (not shown in the figure) is provided in the ultrasonic fixing ring 140. Those skilled in the art can select an appropriate sieve and its installation method according to actual needs to achieve a stable connection between the sieve and the ultrasonic fixing ring 140 and ensure that the material can be dispersed through the sieve, which will not be elaborated here.

[0055] In the actual application process, the ultrasonic generator includes an ultrasonic vibration rod 210, and a vibration clamp 220 cooperating with the ultrasonic fixing ring 140 is provided on the ultrasonic vibration rod 210. After the ultrasonic vibration is turned on, the vibration is transmitted to the ultrasonic fixing ring 140 through the vibration clamp 220. The powder moves from the material bin to the control switch 130 and then to the ultrasonic fixing ring 140 under the action of the ultrasonic vibration. The powder continues to fall to reach the reaction chamber of the quartz tube 470. At this time, the powder is dispersed through the sieve under the action of the ultrasonic vibration, and the nano powder is more uniformly dispersed after treatment, which is beneficial to improving the subsequent treatment effect.

[0056] Preferably, a detachable adapter pipe 150 is provided on the intake adapter 310. The adapter pipe 150 is detachably connected to the ultrasonic fixing ring 140. Sealing rings are provided between the adapter pipe 150 and the ultrasonic fixing ring 140, and between the adapter pipe 150 and the intake adapter 310. One end of the adapter pipe 150 extending into the ultrasonic fixing ring 140 is provided with a flared feed inlet, and the other end extends into the material passing hole 322 to communicate with the plasma reaction chamber.

[0057] Exemplarily, conventional detachable connection methods such as threaded connection can be adopted between the adapter pipe 150 and the ultrasonic fixing ring 140, and between the adapter pipe 150 and the intake adapter 310. By adopting threaded connection and setting sealing rings, stable connections between the adapter pipe 150 and the ultrasonic fixing ring 140, and between the adapter pipe 150 and the intake adapter 310 can be ensured.

[0058] During actual application, by providing a flared opening at one end of the adapter pipe 150 extending into the ultrasonic fixing ring 140, it is beneficial to guide the powder to further move towards the middle of the material passing hole 322, thereby reducing the probability of the powder contacting the inner wall of the quartz tube 470.

[0059] This embodiment also provides a method for microwave plasma spheroidization of micron-sized powder, which is realized based on the above device. The specific steps include:

[0060] Step S1, close the control switch 130, add the powder to be processed, and turn on the powder protection gas in the bin.

[0061] Step S2, turn on the cooling water, plasma gas, and power supply, and start the plasma generator for ignition.

[0062] Step S3, turn on the control switch 130 and the ultrasonic generator 200, and the powder enters the quartz tube 470 for treatment.

[0063] Step S4, collect the powder below the quartz tube 470.

[0064] The device for microwave plasma treatment of nano-powders according to the present invention realizes more uniform and stable microwave plasma. The nano-powders processed absorb microwave energy more uniformly, have better powder sphericity and higher spheroidization rate, improving the quality and efficiency. By adopting the method of ultrasonic vibration, the problem of nano-powder transportation is solved, and uniform transportation of nano-powders can be ensured, which is beneficial to improving the treatment effect. In addition, by adopting a gas distributor, the plasma gas around the nano-powders during treatment is more uniform, the generated plasma is more stable, and the heat absorbed by the nano-powders is more uniform, further improving the treatment effect.

[0065] Note that the above is only the preferred embodiment of the present invention and the technical principles applied. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein. Various obvious changes, re-adjustments, and substitutions can be made by those skilled in the art without departing from the protection scope of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments. Without departing from the concept of the present invention, it may also include more other equivalent embodiments, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A device for treating nanopowders with microwave plasma, characterized in that: It comprises a nano powder feeder (100), an ultrasonic generator (200), a microwave plasma generator (400) and a gas separator (300); The nano powder feeder (100) comprises a powder bin (110) for storing powder materials to be processed; The ultrasonic generator (200) is arranged at the discharge port of the powder bin (110) to drive the powder material to be processed in the powder bin (110) to be discharged from the discharge port; The microwave plasma generator (400) is provided with a plasma reaction chamber, one end of the microwave plasma generator (400) is connected to the discharge port of the powder bin (110) via the gas separator (300), and the other end is provided with a discharge port communicated with the plasma reaction chamber; The gas separator (300) is provided with an air inlet hole (311) and a feed hole (322); one end of the feed hole (322) is connected to the discharge port, and the other end is connected to the plasma reaction chamber; positions corresponding to the feed hole (322) around the gas separator (300) are provided with air holes (321) for connecting the air inlet hole (311) and the plasma reaction chamber; a plurality of air holes (321) are evenly arranged along the circumference of the feed hole (322), so that the gas entering the air inlet hole (311) can be evenly dispersed through the air holes (321) and then enter the plasma reaction chamber and flow in a spiral shape.

2. The device for treating nanopowders with microwave plasma according to claim 1, characterized in that: The gas separator (300) comprises an air inlet adapter (310) and an air separator (320); the air inlet hole (311) is arranged on one side of the air inlet adapter (310); and a flow cavity connected to the air inlet hole (311) exists between the air inlet adapter (310) and the air separator (320); the material passing hole (322) and the air passing hole (321) are both arranged on the air separator (320); each air passing hole (321) is obliquely arranged on the air separator (320); one end of each air passing hole (321) facing upward is connected to the flow cavity, and the other end is connected to the plasma reaction chamber.

3. The device for treating nanopowders with microwave plasma according to claim 2, characterized in that: The air intake adapter (310) is detachably mounted on the microwave plasma generator (400), and an assembly groove that matches the air distributor (320) is provided on the air intake adapter (310).

4. The device for treating nano powder with microwave plasma according to claim 2 or 3, characterized in that: The microwave plasma generator (400) comprises a waveguide (410) and a quartz tube (470) arranged on the waveguide (410); the quartz tube (470) is coaxially arranged with the material passing hole (322); a plasma reaction chamber is arranged in the quartz tube (470); and a water cooling auxiliary device (450) is also arranged at a position on the waveguide (410) corresponding to the quartz tube (470).

5. The device for treating nanopowders with microwave plasma according to claim 4, characterized in that: The quartz tube (470) is detachably mounted on the waveguide (410), and the waveguide (410) is provided with an inner ferrule (440) that matches the quartz tube (470).

6. The device for treating nanopowders with microwave plasma according to claim 5, characterized in that: A gas separation adapter (420) for connecting to the gas inlet adapter (310) is also provided at a position on the waveguide (410) corresponding to the quartz tube (470); one end of the gas separation adapter (420) is provided with an assembly hole that matches the gas separation component (320); the other end is provided with a positioning groove that matches the end of the quartz tube (470); the assembly hole is connected to the positioning groove.

7. The device for treating nano powders with microwave plasma according to claim 6, characterized in that: A first sealing member cooperating with the quartz tube (470) is provided at a position corresponding to the positioning groove on the gas separation adapter (420), and a second sealing member cooperating with the air intake adapter (310) is provided at a position corresponding to the assembly hole on the gas separation adapter (420).

8. The device for treating nano powder with microwave plasma according to claim 2 or 3, characterized in that: An ultrasonic fixing ring (140) for connecting to the ultrasonic generator (200) is provided at a position below the discharge port of the powder bin (110), one end of the ultrasonic fixing ring (140) is connected to the discharge port of the powder bin (110), and the other end is connected to the material passing hole (322) of the gas separator (300), and a screen is provided inside the ultrasonic fixing ring (140).

9. The device for treating nano powders with microwave plasma according to claim 8, characterized in that: The air inlet adapter (310) is provided with a detachable adapter tube (150), and the adapter tube (150) and the ultrasonic fixing ring (140) are detachably connected. Sealing rings are provided between the adapter tube (150) and the ultrasonic fixing ring (140), and between the adapter tube (150) and the air inlet adapter (310). One end of the adapter tube (150) extending into the ultrasonic fixing ring (140) is provided with a trumpet-shaped feed port, and the other end extends into the feed hole (322) to be connected with the plasma reaction chamber.

10. The device for treating nano powders with microwave plasma according to claim 1, characterized in that: An openable and closable bin cover (120) is provided above the powder bin (110), a control switch (130) for controlling the on and off of the discharge port is provided below the powder bin (110) at a position corresponding to the discharge port, and a protective gas inlet (121) is provided on the bin cover (120).

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