Low-pressure jet plasma enhanced chemical vapor deposition equipment and production method thereof

Abstract

The invention discloses low-air-pressure jet plasma enhanced chemical vapor deposition equipment and a production method thereof, and relates to the field of chemical vapor deposition. The low-air-pressure jet plasma enhanced chemical vapor deposition equipment comprises a plasma generator, a cracking cavity, a growth cavity and a recovery device which are connected in sequence; channels which are communicated in sequence are formed in the plasma generator, the cracking cavity, the growth cavity and the recovery device; the growth cavity is used for conveying metal particles into the growth cavity; an outlet of the growth cavity is connected with a recovery device through a conveying pipeline; and the metal particles can enter the recovery device through a channel between the inner cavity of the growth cavity and the interior of the conveying pipeline under the action of gravity. By adopting the scheme, the metal particle powder can directly penetrate through the plasma to complete the solid-state membrane in-situ production reaction on the surfaces of the metal particles, so that the in-situ reaction time reaches millisecond magnitude, and compared with the traditional PECVD equipment, the reaction time is greatly shortened, so that the production / experiment efficiency is improved.

Description

Technical Field

[0001] The invention relates to the field of chemical vapor deposition, and in particular to a low-pressure jet plasma enhanced chemical vapor deposition device and a production method thereof. Background Art

[0002] Plasma enhanced chemical vapor deposition, referred to as PECVD, is a technology that uses plasma to activate reactive gases, promotes chemical reactions of reactive gases on the substrate surface or near the surface space, and generates solid films. The difference between PECVD and traditional CVD technology is that the source gas is ionized into plasma, and the substrate is immersed in or placed under the plasma. The plasma contains a large number of high-energy electrons, and the temperature of these electrons can reach 10000K. The collision of electrons with gas phase molecules can promote the chemical bond breaking and recombination of reactive gas molecules, generate more active chemical groups and adsorb on the substrate surface to form a solid film. It is a form of in-situ growth and is widely used to form solid coatings on the surface of metal particles.

[0003] At present, the PECVD device commonly used in laboratories to grow solid coatings on the surface of metal particles mainly includes: vacuum chamber, radio frequency (RF) power supply, upper and lower electrodes and vacuum pump system. The vacuum chamber usually uses a large diameter synthetic quartz glass tube as the substrate tube. The substrate (metal or metal particles) is placed in the quartz glass tube, and the substrate is heated by an external heating source during the experiment. This method can only grow solid films on the surface of small batches of substrates. If large batches need to be prepared, the equipment needs to be started and stopped repeatedly, and the substrate needs to be heated before and during the growth of the solid film, which undoubtedly greatly increases the experimental time cost and energy consumption cost. Summary of the invention

[0004] The present invention aims to solve the deficiencies of the prior art and to provide a low-pressure jet plasma enhanced chemical vapor deposition device and a production method thereof. By adopting this solution, metal particle powder can directly pass through the plasma to complete the in-situ production reaction of the solid film on the surface of the metal particles, so that the in-situ reaction time reaches the millisecond level. Compared with traditional PECVD equipment, the reaction time is greatly shortened, thereby improving the production / experimental efficiency.

[0005] The present invention is achieved through the following technical solutions:

[0006] Low-pressure jet plasma enhanced chemical vapor deposition equipment, including:

[0007] A plasma generator, a cracking chamber, a growth chamber and a recovery device are connected in sequence, wherein the plasma generator, the cracking chamber, the growth chamber and the recovery device form a channel connected in sequence;

[0008] The plasma generator is used to generate plasma, and the plasma is transported into the cracking chamber through a built-in channel;

[0009] The cracking chamber is used to input the reaction gas, crack the reaction gas introduced into the channel and generate chemically active groups; at the same time, the plasma containing the active groups is transported to the growth chamber through the channel;

[0010] The growth chamber is used to transport metal particles and react with plasma containing active groups;

[0011] The outlet of the growth cavity is connected to the recovery device through a conveying pipeline; the metal particles can enter the centrifugal rotation separation device through the channel between the inner cavity of the growth cavity and the inside of the conveying pipeline under the action of gravity.

[0012] Compared with the prior art, only a small batch of substrate surfaces can be coated with solid films for growth. If a large batch needs to be prepared, the equipment needs to be repeatedly started and stopped, and the metal particle substrate needs to be additionally heated before and during the growth of the solid film. This undoubtedly greatly increases the experimental time cost and energy consumption cost. The present invention provides a low-pressure jet plasma enhanced chemical vapor deposition equipment and a production method thereof. By adopting this scheme, metal particle powder can directly pass through the plasma to complete the in-situ production reaction of the solid film on the surface of the metal particle, so that the in-situ reaction time reaches the millisecond level. Compared with traditional PECVD equipment, the reaction time is greatly shortened, thereby improving the production / experimental efficiency. The specific scheme includes a plasma generator, a cracking chamber, a growth chamber and a recovery device, wherein the plasma generator is arranged at the top of the equipment, and is used to introduce a high-frequency DC power supply and generate plasma; the cracking chamber is arranged at the lower end of the plasma generator, and is used to crack the reaction gas to generate chemically active groups; the growth chamber is arranged at the lower end of the cracking chamber, and is used to transport metal particle powder; the lower end of the growth chamber is connected to the recovery device through a transport pipeline, and is used to recover the reaction product; wherein, when the metal particle powder is transported into the growth chamber, the channel inside the growth chamber is already full of plasma, and the metal particle powder transported into the growth chamber can directly enter the plasma, At this time, the metal particles pass through the plasma and can complete the in-situ growth reaction of the surface solid film in a very short time, and then enter the recovery device by free fall; wherein, the channel between the inner cavity of the growth chamber and the inside of the conveying pipe can be vertical, downward inclined or downward bent, so that the metal particles can freely fall under the action of their own gravity to enter the recovery device; the above scheme can greatly reduce the design requirements of the vacuum system of the equipment; at the same time, the metal particles are directly sent into the plasma, so that the in-situ reaction time reaches the millisecond level, reducing the time for the metal particle powder surface to complete the solid film growth; not only shortening the reaction time, but also improving the production and experimental efficiency.

[0013] In order to cool the cracking chamber during the operation of the equipment, the outer wall of the cracking chamber is provided with a reaction gas inlet connected to the channel;

[0014] The side wall of the cracking chamber is provided with a first cooling water loop, and the outer side wall of the cracking chamber is also provided with a first cooling water inlet and a first cooling water outlet which are connected with the first cooling water loop.

[0015] In order to facilitate the delivery of cooling gas and metal particles into the growth chamber, the outer wall of the growth chamber is provided with a cooling gas inlet and a metal particle delivery port connected to the channel. The delivery of cooling gas can be used to adjust the plasma temperature, prevent the plasma temperature through which the metal particles pass through from being too high, and prevent the gas temperature entering the recovery device and the vacuum system from being too high; in addition, the delivery pipeline is equivalent to a cooling chamber, and through its own sufficient length, it is used to naturally cool the gas generated during the operation and extracted by the vacuum system when the equipment is working, that is, to cool the gas heated by the plasma in the working state, and at the same time serve as a transition channel for the metal particles that have completed in-situ growth in the plasma to enter the lower end of the centrifugal rotating separation tank unit.

[0016] In order to cool the growth chamber during operation, the side wall of the growth chamber is provided with a second cooling water circuit, and the outer side wall of the growth chamber is also provided with a second cooling water inlet and a second cooling water outlet connected to the second cooling water circuit. The first cooling water circuit and the second cooling water circuit can both be bolted or annularly arranged to achieve cooling in the circumferential direction; the first cooling water circuit and the second cooling water circuit are both stainless steel.

[0017] In order to facilitate observation of the plasma state and the falling state of the metal particles, the plasma generator, the cracking chamber, the growth chamber and the conveying pipeline are arranged in sequence from top to bottom, and an observation chamber is also arranged between the growth chamber and the conveying pipeline, and the side wall of the observation chamber is made of transparent material. In this solution, the observation chamber is arranged at the lower end of the growth chamber, and preferably quartz glass is used as the side wall. Except for the observation chamber part which is made of quartz glass, the other chambers are made of stainless steel, and the connection between the chambers is made of standard flange interfaces.

[0018] Since the metal particles are micron-sized, they are very easy to adhere to the side wall of the recovery device. Therefore, in order to avoid the adhesion of metal particles, the recovery device is a centrifugal rotary separation tank, the centrifugal rotary separation tank is connected to the outlet of the conveying pipeline, and the bottom outlet of the centrifugal rotary separation tank is provided with a product collection tank. A sealed isolation valve is provided between the bottom outlet of the centrifugal rotary separation tank and the product collection tank. In this scheme, a centrifugal rotary separation tank is used to collect the metal particle powder after the solid coating reaction is completed, and the metal particles adhering to the side wall are separated by the centrifugal action of the centrifugal rotary separation tank, and fall downward into the product collection tank; in addition, a sealed isolation valve is also provided between the centrifugal rotary separation tank unit and the product collection tank. The sealed isolation valve design ensures that the metal particle powder after the reaction is completed is collected without destroying the vacuum degree of the equipment. At the same time, this design can greatly save the preliminary preparation time required for the next production / experiment, and prevent the air from entering the equipment when the equipment is still at high temperature after the reaction is completed. The damage to each unit inside the equipment, especially the graphite sleeve (such as oxidation), undoubtedly extends the service life of each system of the equipment, especially the vacuum system.

[0019] In order to further collect the metal particles and powder that may adhere to the inner wall of the equipment and the metal filter sleeve, a dust collector is also provided on the outer wall of the centrifugal rotary separation tank; the lower end of the centrifugal rotary separation tank is provided with a shock absorber for support. The dust collector is arranged on the outer wall of the centrifugal rotary separation tank, and is used to collect the metal particles and powder that may adhere to the inner wall of the equipment and the metal filter sleeve after the production / experiment is completed; the lower end of the centrifugal rotary separation tank is provided with a shock absorber, which is composed of three legs with an angle of 120° between them, and is used to support the entire equipment. An elastic buffer device is provided at the leg to prevent vibration from damaging the equipment when the dust collector is turned on.

[0020] In order to indirectly measure the temperature of the inner wall of the cracking chamber and the growth chamber and the gas temperature at the connection between the centrifugal rotating separation tank and the delivery pipeline, and accurately control the reaction temperature, the cracking chamber is provided with a first temperature measuring port, the growth chamber is provided with a second temperature measuring port, and the recovery device is provided with a third temperature measuring port, and the first temperature measuring port, the second temperature measuring port and the third temperature measuring port are all used to install thermocouples;

[0021] The cracking chamber and the growth chamber are both provided with a graphite sleeve as an inner layer, and the thermocouples on the first temperature measuring port and the second temperature measuring port are both used to indirectly measure the temperature of the inner wall of the graphite sleeve when the device is working;

[0022] The measuring end of the thermocouple on the third temperature measuring port extends to the center of the tail end of the delivery pipeline. In this scheme, a graphite sleeve is provided as an inner layer in the plasma generator, the cracking chamber, and the growth chamber to prevent the internal temperature from being too high during operation and ablating the cooling water channel; channels for placing thermocouples are drilled on the graphite sleeve inside the cracking chamber and the growth chamber, namely the first temperature measuring port and the second temperature measuring port, but the graphite sleeve is not drilled through. The channel port is about 3 mm away from the inner wall of the graphite sleeve. The thermocouple used for real-time measurement of the temperature changes inside the cracking chamber and the growth chamber during the experiment is inserted into the graphite sleeve through the first temperature measuring port and the second temperature measuring port. In the process, the internal temperature is indirectly measured through the side wall so that the thermocouple does not come into contact with the internal high-temperature gas. At the same time, to ensure the vacuum degree of the equipment, the connection end of the thermocouple and the temperature measuring port adopts a standard KF sealing flange; and the third temperature measuring port arranged on the top of the centrifugal rotating separation tank is used to measure the temperature of the reaction gas at the tail end of the conveying pipeline. The thermocouple installed on the third temperature measuring port is a customized thermocouple, and its measuring end can just extend to the center of the tail end of the conveying pipeline. Considering the vacuum degree requirements, the connection between the thermocouple and the third temperature measuring port also adopts a standard KF sealing flange interface.

[0023] In order to evacuate the interior of the equipment and detect the vacuum degree before and after the equipment is operated, as well as to prevent metal particles from entering the vacuum system, the top of the recovery device is also provided with a vacuum suction port and a vacuum measurement port connected to the interior. The vacuum suction port is used to connect to the vacuum system, and the recovery device is connected to the vacuum suction port through a micron-grade metal filter sleeve.

[0024] In addition, the present invention also provides a gas supply unit, which is arranged outside each cylinder and is used to provide various process gases to the plasma generator, the cracking chamber, and the growth chamber, and the gas supply unit is independently arranged; wherein the cooling gas delivered to the plasma generator and the cracking chamber and the gas delivered to the metal particle powder into the growth chamber through the gas feeder are the same medium gas. A float flowmeter or a mass flow controller is used in the gas supply unit to accurately control the gas flow.

[0025] In a further embodiment, the present invention also provides a method for producing a low-pressure jet plasma enhanced chemical vapor deposition device, comprising the following steps:

[0026] The channel is evacuated to a vacuum state at the recovery device;

[0027] supplying gas to the interior of the plasma generator and generating plasma through the plasma generator;

[0028] The plasma is transported to the cracking chamber, and by transporting the reaction gas into the cracking chamber, the reaction gas undergoes a cracking reaction under the action of the plasma and generates chemically active groups;

[0029] The plasma containing chemically active groups is transported to the growth chamber through the internal channel of the cracking chamber, and cooling gas and metal particles are transported into the growth chamber, so that the metal particles pass through the plasma in the channel and an in-situ growth reaction of the surface solid film occurs;

[0030] Then, under the action of gravity, the metal particles enter the centrifugal rotating separation device through the conveying pipe for recovery.

[0031] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0032] 1. The present invention provides a low-pressure jet plasma enhanced chemical vapor deposition equipment and a production method thereof. By adopting this solution, metal particle powder can directly pass through the plasma to complete the in-situ production reaction of the solid film on the surface of the metal particles, so that the in-situ reaction time reaches the millisecond level. Compared with traditional PECVD equipment, the reaction time is greatly shortened, thereby improving the production / experimental efficiency.

[0033] 2. The low-pressure jet plasma enhanced chemical vapor deposition equipment and production method provided by the present invention reduce the requirements for vacuum degree during the experiment and simplify the design requirements of the equipment vacuum system.

[0034] 3. The present invention provides a low-pressure jet plasma enhanced chemical vapor deposition equipment and a production method thereof. The sealed isolation valve design adopted ensures that the metal particle powder after the reaction is completed can be collected without destroying the vacuum degree of the equipment. At the same time, the design can greatly save the preliminary preparation time required for the next production / experiment, and prevent the air from entering the equipment when the equipment is still at a high temperature after the reaction is completed, causing damage (such as oxidation) to the internal units of the equipment, especially the graphite sleeve. This undoubtedly extends the service life of the various systems of the equipment, especially the vacuum system. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and should not be regarded as limiting the scope. For those of ordinary skill in the art, other relevant drawings can be obtained based on these drawings without creative work. In the drawings:

[0036] Figure 1 A schematic diagram of the overall structure of the low-pressure jet plasma enhanced chemical vapor deposition equipment provided by the present invention;

[0037] Figure 2 A cross-sectional view of a cracking chamber provided by the present invention;

[0038] Figure 3 A cross-sectional view of a growth chamber provided by the present invention.

[0039] Marks and corresponding parts names in the attached drawings:

[0040] 1-plasma generator, 2-cracking chamber, 3-growth chamber, 4-observation chamber, 5-conveying pipeline, 6-recovery device, 7-product collection tank, 8-dust collector and vibrator, 9-shock absorber, 10-1-first cooling water inlet, 10-2-first cooling water outlet, 11-reaction gas inlet, 12-first temperature measuring port, 13-cooling gas inlet, 14-metal particle conveying port, 15-1-second cooling water inlet, 15-2-second cooling water outlet, 16-second temperature measuring port, 17-sealed isolation valve, 18-third temperature measuring port, 19-vacuum measuring port, 20-vacuum exhaust port, 21-gas supply unit. DETAILED DESCRIPTION

[0041] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments and drawings. The exemplary embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention.

[0042] Embodiment 1:

[0043] This embodiment 1 provides a low-pressure jet plasma enhanced chemical vapor deposition device, such as Figure 1-Figure 3 As shown, Figure 1 The middle right picture is a schematic diagram of the structure of the low-pressure jet plasma enhanced chemical vapor deposition equipment. Figure 1 The left figure in the middle is a schematic diagram of the structure of the air supply unit 21; Figure 2 The lower middle figure is a top view of the cracking chamber 2. Figure 2 The upper middle figure is a cross-sectional view of the cracking chamber 2; Figure 3 The lower middle figure is a top view of the growth cavity 3; Figure 3 The upper middle figure is a cross-sectional view of the growth chamber 3 .

[0044] A low-pressure jet plasma enhanced chemical vapor deposition device, comprising:

[0045] A plasma generator 1, a cracking chamber 2, a growth chamber 3 and a recovery device 6 are connected in sequence, wherein the plasma generator 1, the cracking chamber 2, the growth chamber 3 and the recovery device 6 form a channel that is connected in sequence;

[0046] The plasma generator 1 is used to generate plasma, and the plasma is transported to the cracking chamber 2 through a built-in channel;

[0047] The cracking chamber 2 is used to input the reaction gas, crack the reaction gas introduced into the channel and generate chemically active groups; at the same time, the plasma containing the chemically active groups is transported to the growth chamber 3 through the channel;

[0048] The growth chamber 3 is used to transport metal particles and react with plasma containing active groups;

[0049] The outlet of the growth cavity 3 is connected to the recovery device 6 via the delivery pipe 5; the metal particles can enter the recovery device 6 through the channel between the inner cavity of the growth cavity 3 and the inside of the delivery pipe 5 under the action of gravity.

[0050] Compared with the prior art, only a small batch of substrate surfaces can be coated with solid films for growth. If a large batch needs to be prepared, the equipment needs to be repeatedly started and stopped, and the metal particle substrate needs to be additionally heated before and during the growth of the solid film. This undoubtedly greatly increases the experimental time cost and energy consumption cost. The present invention provides a low-pressure jet plasma enhanced chemical vapor deposition equipment and a production method thereof. By adopting this scheme, metal particle powder can directly pass through the plasma to complete the in-situ production reaction of the solid film on the surface of the metal particle, so that the in-situ reaction time reaches the millisecond level. Compared with traditional PECVD equipment, the reaction time is greatly shortened, thereby improving the production / experimental efficiency. In the specific scheme, it includes a plasma generator 1, a cracking chamber 2, a growth chamber 3 and a recovery device 6, wherein the plasma generator 1 is arranged at the top of the equipment, and is used to introduce a high-frequency DC power supply and generate plasma; the cracking chamber 2 is arranged at the lower end of the plasma generator 1, and is used to crack the reaction gas to generate chemically active groups; the growth chamber 3 is arranged at the lower end of the cracking chamber 2, and is used to transport metal particle powder; the lower end of the growth chamber 3 is connected to the recovery device 6 through a transport pipeline 5, and is used to recover the reaction product; wherein, when the metal particle powder is transported into the growth chamber 3, the channel inside the growth chamber 3 is already full of plasma, and the metal particle powder transported into the growth chamber 3 can directly enter the etc. In the plasma, the metal particles pass through the plasma and can complete the in-situ growth reaction of the surface solid film in a very short time, and then enter the recovery device 6 by free fall; wherein, the channel between the inner cavity of the growth chamber 3 and the inside of the conveying pipe 5 can be vertical, inclined downward or bent downward, so that the metal particles can freely fall under the action of their own gravity to enter the recovery device 6; the above scheme can greatly reduce the design requirements of the vacuum system of the equipment; at the same time, the metal particles are directly sent into the plasma, so that the in-situ reaction time reaches the millisecond level, reducing the time for the metal particle powder surface to complete the solid film growth; not only shortening the reaction time, but also improving the production and experimental efficiency.

[0051] In order to cool the cracking chamber 2 during the operation of the equipment, the outer wall of the cracking chamber 2 is provided with a reaction gas inlet 11 connected to the channel;

[0052] The side wall of the cracking chamber 2 is provided with a first cooling water circuit, and the outer side wall of the cracking chamber 2 is also provided with a first cooling water inlet 10-1 and a first cooling water outlet 10-2 connected to the first cooling water circuit.

[0053] In order to facilitate the delivery of cooling gas and metal particles into the growth chamber 3, the outer wall of the growth chamber 3 is provided with a cooling gas inlet 13 and a metal particle delivery port 14 connected to the channel. The delivery of cooling gas can be used to adjust the plasma temperature, prevent the plasma temperature through which the metal particles pass through from being too high, and prevent the gas temperature entering the recovery device 6 and the vacuum system from being too high; in addition, the delivery pipeline 5 is equivalent to a cooling chamber, and through its own sufficient length, it is used to naturally cool the gas generated during the operation and extracted by the vacuum system when the equipment is working, that is, to cool the gas heated by the plasma in the working state, and at the same time, it serves as a transition channel for the metal particles that have completed in-situ growth in the plasma to enter the lower end of the centrifugal rotating separation tank unit.

[0054] In order to cool the growth chamber 3 during operation, the side wall of the growth chamber 3 is provided with a second cooling water circuit, and the outer wall of the growth chamber 3 is also provided with a second cooling water inlet 15-1 and a second cooling water outlet 15-2 connected to the second cooling water circuit. The first cooling water circuit and the second cooling water circuit can be bolted or annularly arranged to achieve cooling in the circumferential direction; the first cooling water circuit and the second cooling water circuit are both made of stainless steel.

[0055] In order to facilitate observation of the plasma state and the falling state of the metal particles, the plasma generator 1, the cracking chamber 2, the growth chamber 3 and the conveying pipe 5 are arranged in sequence from top to bottom, and an observation chamber 4 is also arranged between the growth chamber 3 and the conveying pipe 5, and the side wall of the observation chamber 4 is made of transparent material. In this solution, the observation chamber 4 is arranged at the lower end of the growth chamber 3, and preferably uses quartz glass as the side wall. Except for the observation chamber 4 part which uses quartz glass, the other chambers are all made of stainless steel, and the connection between the chambers is made of standard flange interfaces.

[0056] Since the metal particles are in the micron level, they are very easy to adhere to the side wall of the recovery device 6. Therefore, in order to avoid the adhesion of metal particles, the recovery device 6 is a centrifugal rotary separation tank, and the centrifugal rotary separation tank is connected to the outlet of the conveying pipeline 5. The bottom outlet of the centrifugal rotary separation tank is provided with a product collection tank 7, and a sealed isolation valve 17 is provided between the bottom outlet of the centrifugal rotary separation tank and the product collection tank 7. In the present solution, a centrifugal rotating separation tank is used to collect the metal particle powder after the solid coating reaction is completed. The centrifugal action of the centrifugal rotating separation tank is then used to separate the metal particles adhering to the side wall and drop downward into the product collection tank 7. In addition, a sealed isolation valve 17 is provided between the centrifugal rotating separation tank unit and the product collection tank 7. The design of the sealed isolation valve 17 ensures that the metal particle powder after the reaction is completed is collected without destroying the vacuum degree of the equipment. At the same time, this design can greatly save the preliminary preparation time required for the next production / experiment, and prevents the air from entering the equipment when the equipment is still at a high temperature after the reaction is completed, causing damage (such as oxidation) to the various units inside the equipment, especially the graphite sleeve. This undoubtedly extends the service life of various systems of the equipment, especially the vacuum system.

[0057] In order to further collect the metal particle powder that may adhere to the inner wall of the equipment and the metal filter sleeve, a dust collector rapper 8 is also provided on the outer wall of the centrifugal rotary separation tank; the lower end of the centrifugal rotary separation tank is provided with a shock absorber seat 9 for support. The dust collector rapper 8 is arranged on the outer wall of the centrifugal rotary separation tank, and is used to collect the metal particle powder that may adhere to the inner wall of the equipment and the metal filter sleeve after the production / experiment is completed; the lower end of the centrifugal rotary separation tank is provided with a shock absorber seat 9, which is three legs with an angle of 120° between the three legs, and is used to support the entire equipment. An elastic buffer device is provided at the leg to prevent vibration from damaging the equipment during the period when the dust collector rapper 8 is turned on.

[0058] In order to indirectly measure the inner wall temperature of the cracking chamber 2 and the growth chamber 3 and the gas temperature at the connection between the centrifugal rotating separation tank and the conveying pipeline 5, and accurately control the reaction temperature, the cracking chamber 2 is provided with a first temperature measuring port 12, the growth chamber 3 is provided with a second temperature measuring port 16, and the recovery device 6 is provided with a third temperature measuring port 18, and the first temperature measuring port 12, the second temperature measuring port 16 and the third temperature measuring port 18 are all used to install thermocouples;

[0059] The cracking chamber 2 and the growth chamber 3 are both provided with a graphite sleeve as an inner layer, and the thermocouples on the first temperature measuring port 12 and the second temperature measuring port 16 are both used to indirectly measure the temperature of the inner wall of the graphite sleeve;

[0060] The measuring end of the thermocouple on the third temperature measuring port 18 extends to the center of the tail end of the delivery pipe 5. In this scheme, a graphite sleeve as an inner layer is provided in the plasma generator 1, the cracking chamber 2, and the growth chamber 3 to prevent the internal temperature from being too high during operation and ablating the cooling water channel; channels for placing thermocouples, namely the first temperature measuring port 12 and the second temperature measuring port 16, are drilled on the graphite sleeve inside the cracking chamber 2 and the growth chamber 3, but the graphite sleeve is not drilled through, and the channel port is about 3 mm away from the inner wall of the graphite sleeve. The thermocouples used for real-time measurement of the temperature changes inside the cracking chamber 2 and the growth chamber 3 during the experiment are inserted into the graphite sleeve through the first temperature measuring port 12 and the second temperature measuring port 16. In the ink sleeve, the internal temperature is measured indirectly through the side wall so that the thermocouple does not come into contact with the internal high-temperature gas. At the same time, to ensure the vacuum degree of the equipment, the connection end of the thermocouple and the temperature measuring port adopts a standard KF sealing flange; and the third temperature measuring port 18 arranged on the top of the centrifugal rotating separation tank is used to measure the temperature of the reaction gas at the tail end of the conveying pipeline 5. The thermocouple installed in the third temperature measuring port 18 is a customized thermocouple, and its measuring end can just extend to the center of the tail end of the conveying pipeline 5. Considering the vacuum degree requirements, the connection between the thermocouple and the third temperature measuring port 18 also adopts a standard KF sealing flange interface.

[0061] In order to evacuate the inside of the equipment and detect the vacuum degree before and after the equipment is operated, and to prevent metal particles from entering the vacuum system, the top of the recovery device 6 is also provided with a vacuum suction port 20 and a vacuum measurement port 19 connected to the inside. The vacuum suction port 20 is used to connect to the vacuum system, and the recovery device 6 is connected to the vacuum suction port 20 through a micron-grade metal filter sleeve.

[0062] In addition, the present solution is further provided with a gas supply unit 21, which is arranged outside each cylinder and is used to provide various process gases to the plasma generator 1, the cracking chamber 2, and the growth chamber 3, and the gas supply unit 21 is independently arranged; wherein, the cooling gas delivered to the plasma generator 1 and the cracking chamber 2 and the gas delivered to the metal particle powder into the growth chamber 3 through the gas feeder are the same medium gas. A float flowmeter or a mass flow controller is used in the gas supply unit 21 to accurately control the gas flow.

[0063] Embodiment 2:

[0064] This embodiment 2 is further optimized on the basis of embodiment 1, and also provides a production method of a low-pressure jet plasma enhanced chemical vapor deposition device, including the following specific steps:

[0065] The vacuum inside the PECVD equipment is evacuated to 10 -1 Pa level, thereby excluding the internal gas.

[0066] Then, the gas supply unit 21 is turned on and adjusted to deliver plasma generating gas only to the plasma generator 1 unit, and the vacuum degree inside the equipment is adjusted to 10 2 Pa level, after the gas flow and vacuum are stable, the plasma generator 1 is turned on to generate plasma. Since gas will be introduced into the device during operation, which will affect the internal air pressure, the vacuum system is required to control the internal vacuum of the device so that it can be continuously stabilized at 10 2 Pa level.

[0067] The plasma is transported to the cracking chamber 2, and the gas supply unit 21 is adjusted to transport the reaction gas to the cracking chamber 2 through the reaction gas inlet 11. After the cracking reaction is stable, the gas supply unit 21 is adjusted to transport the gas to the growth chamber 3 through the cooling gas inlet 13 to adjust the plasma temperature, and the plasma is transported to the growth chamber 3.

[0068] The gas supply unit 21 is adjusted again, and the metal particle powder is delivered to the plasma in the growth chamber 3 through the metal particle delivery port 14 using a gas feeder. The metal particles pass through the plasma and complete the surface solid film in situ growth reaction in a very short time, and then fall freely through the delivery pipe 5, that is, the cooling chamber and fall into the bottom of the centrifugal rotating separation tank unit.

[0069] After the in-situ growth reaction is completed, the plasma generator 1 is turned off, the gas supply unit 21 is turned off, the sealed isolation valve 17 is opened, and the dust collector rapper 8 is turned on. After the metal particles that have completed the in-situ reaction fall into the product collection tank 7, the sealed isolation valve 17 is closed and the product collection tank 7 is removed to complete the entire process.

[0070] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. Low-pressure jet plasma enhanced chemical vapor deposition equipment, characterized in that: include: A plasma generator (1), a cracking chamber (2), a growth chamber (3) and a recovery device (6) connected in sequence, wherein the plasma generator (1), the cracking chamber (2), the growth chamber (3) and the recovery device (6) form channels that are connected in sequence; The plasma generator (1) is used to generate plasma, and the plasma is transported to the cracking chamber (2) through a built-in channel; The cracking chamber (2) is used to input reaction gas, crack the reaction gas introduced into the channel and generate chemically active groups; at the same time, the plasma containing the active groups is transported to the growth chamber (3) through the channel; The growth chamber (3) is used to transport metal particles and react with plasma containing active groups; The outlet of the growth cavity (3) is connected to a recovery device (6) via a delivery pipe (5); the metal particles can pass through a channel between the inner cavity of the growth cavity (3) and the inside of the delivery pipe (5) under the action of gravity and enter the recovery device (6).

2. The low-pressure jet plasma enhanced chemical vapor deposition equipment according to claim 1, characterized in that: The outer wall of the cracking chamber (2) is provided with a reaction gas inlet (11) connected to the channel; The side wall of the cracking chamber (2) is provided with a first cooling water circuit, and the outer side wall of the cracking chamber (2) is also provided with a first cooling water inlet (10-1) and a first cooling water outlet (10-2) connected to the first cooling water circuit.

3. The low-pressure jet plasma enhanced chemical vapor deposition equipment according to claim 1, characterized in that: The outer side wall of the growth cavity (3) is provided with a cooling gas inlet (13) and a metal particle delivery port (14) which are connected to the channel.

4. The low-pressure jet plasma enhanced chemical vapor deposition equipment according to claim 1, characterized in that: The side wall of the growth cavity (3) is provided with a second cooling water circuit, and the outer side wall of the growth cavity (3) is also provided with a second cooling water inlet (15-1) and a second cooling water outlet (15-2) connected to the second cooling water circuit.

5. The low-pressure jet plasma enhanced chemical vapor deposition equipment according to claim 1, characterized in that: The plasma generator (1), the cracking chamber (2), the growth chamber (3) and the conveying pipeline (5) are arranged in sequence from top to bottom, and an observation chamber (4) is also arranged between the growth chamber (3) and the conveying pipeline (5), and the side wall of the observation chamber (4) is made of transparent material.

6. The low-pressure jet plasma enhanced chemical vapor deposition equipment according to claim 1, characterized in that: The recovery device (6) is a centrifugal rotary separation tank, which is connected to the outlet of the conveying pipeline (5). The bottom outlet of the centrifugal rotary separation tank is provided with a product collection tank (7), and a sealed isolation valve (17) is provided between the bottom outlet of the centrifugal rotary separation tank and the product collection tank (7).

7. The low-pressure jet plasma enhanced chemical vapor deposition equipment according to claim 6, characterized in that: A dust collecting vibrator (8) is also provided on the outer side wall of the centrifugal rotary separation tank; and a shock absorbing seat (9) for support is provided at the lower end of the centrifugal rotary separation tank.

8. The low-pressure jet plasma enhanced chemical vapor deposition equipment according to claim 1, characterized in that: The pyrolysis chamber (2) is provided with a first temperature measuring port (12), the growth chamber (3) is provided with a second temperature measuring port (16), and the recovery device (6) is provided with a third temperature measuring port (18), and the first temperature measuring port (12), the second temperature measuring port (16) and the third temperature measuring port (18) are all used to install thermocouples; The cracking chamber (2) and the growth chamber (3) are both provided with a graphite sleeve as an inner layer, and the thermocouples on the first temperature measuring port (12) and the second temperature measuring port (16) are both used to indirectly measure the temperature of the inner wall of the graphite sleeve when the device is working; The measuring end of the thermocouple on the third temperature measuring port (18) extends to the center of the tail end of the conveying pipeline (5).

9. The low-pressure jet plasma enhanced chemical vapor deposition equipment according to claim 1, characterized in that: The top of the recovery device (6) is also provided with a vacuum suction port (20) and a vacuum measurement port (19) which are connected to the interior. The vacuum suction port (20) is used to be connected to a vacuum system, and the recovery device (6) is connected to the vacuum suction port (20) via a micron-grade metal filter sleeve.

10. The method for producing a low-pressure jet plasma enhanced chemical vapor deposition device according to any one of claims 1 to 9, characterized in that: The following steps are involved: At the recovery device (6), the interior of the equipment is pumped down to <10 -1 Vacuum state of Pa; Supplying gas to the interior of the plasma generator (1) and generating plasma through the plasma generator (1); After the plasma is transported to the cracking chamber (2), a reaction gas is transported into the cracking chamber (2), and the reaction gas undergoes a cracking reaction under the action of the plasma to generate chemically active groups; Plasma containing chemically active groups is transported to the growth chamber (3) through the internal channel of the cracking chamber (2), and cooling gas and metal particles are transported into the growth chamber (3), so that the metal particles pass through the plasma in the channel and an in-situ growth reaction of a surface solid film occurs; Then, the metal particles enter the recovery device (6) through the conveying pipe (5) under the action of gravity for recovery.

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