Low pressure fluidized bed plasma enhanced chemical vapor deposition apparatus and method of production

Abstract

The application discloses a kind of low pressure jet flow plasma enhanced chemical vapor deposition equipment and its production method, it is related to chemical vapor deposition field, including: plasma generator, cleavage cavity, growth cavity and recovery device connected in sequence, the plasma generator, cleavage cavity, growth cavity and recovery device inside form the channel of sequential communication;The growth cavity is used to transport metal particles inside;The outlet of the growth cavity is connected by transport pipeline and recovery device;The metal particles can pass through the channel between the growth cavity inner cavity and the inside of the transport pipeline under the action of gravity, into the recovery device inside.Adopting the present scheme, metal particle powder can directly pass through plasma to complete in-situ production reaction of solid film on the surface of metal particle, so that in-situ reaction time reaches millisecond order, compared with traditional PECVD equipment, reaction time is greatly shortened, thereby improving production / experiment efficiency.

Description

Technical Field

[0001] The present 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, or PECVD, is a technology that uses plasma to activate reactive gases, promoting chemical reactions on or near the substrate surface to form a solid film. PECVD differs from traditional CVD in that the source gas is ionized into a plasma, and the substrate is immersed in or placed beneath the plasma. The plasma contains a large number of high-energy electrons, whose temperatures can reach 10,000 K. The collisions between these electrons and gas-phase molecules can break and recombine the chemical bonds of the reactive gas molecules, generating more active chemical groups that adsorb onto the substrate surface to form a solid film. This is a form of in-situ growth and is widely used to form solid coatings on metal particles.

[0003] Currently, the PECVD apparatus commonly used in laboratories for growing solid-state coatings on metal particles consists primarily of a vacuum chamber, a radio frequency (RF) power supply, upper and lower electrodes, and a vacuum pump system. The vacuum chamber typically utilizes a large-diameter synthetic quartz glass tube as a substrate, within which the substrate (metal or metal particles) is placed. This tube is then heated by an external heating source during the experiment. This method is only suitable for growing solid-state coatings on small batches of substrates. Large-scale preparation requires repeated startup and shutdown of the apparatus, and additional substrate heating is required both before and during solid-state film growth, significantly increasing experimental time and energy costs. Summary of the Invention

[0004] The present invention aims to address 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-state 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 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 that is 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 a recovery device through a conveying pipe; the metal particles can enter the centrifugal separation device through the channel between the inner cavity of the growth cavity and the inside of the conveying pipe under the action of gravity.

[0012] Compared with the existing technology, solid-state film coating and growth can only be performed on small batches of substrate surfaces. If large batches are 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-state 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 solution, metal particle powder can directly pass through the plasma to complete the in-situ production reaction of the solid-state 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 set at the top of the equipment, used to introduce a high-frequency DC power supply and generate plasma; the cracking chamber is set at the lower end of the plasma generator, used to crack the reaction gas to produce chemically active groups; the growth chamber is set at the lower end of the cracking chamber, used to transport metal particle powder; the lower end of the growth chamber is connected to the recovery device through a conveying pipe, used to recover the reaction products; wherein, when the metal particle powder is transported into the growth chamber, the channel inside the growth chamber is already filled with 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 through free fall; wherein, the channel between the inner cavity of the growth chamber and the inside of the conveying pipe can be vertical, downwardly inclined or downwardly 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 fed into the plasma, so that the in-situ reaction time reaches the millisecond level, reducing the time for the solid film growth to be completed on the surface of the metal particle powder; not only shortening the reaction time, but also improving production and experimental efficiency.

[0013] In order to cool the cracking cavity during the operation of the device, the outer side wall of the cracking cavity is provided with a reaction gas inlet communicated with the channel;

[0014] The side wall of the cracking cavity is provided with a first cooling water circuit, and the outer side wall of the cracking cavity is further provided with a first cooling water inlet communicated with the first cooling water circuit and a first cooling water outlet.

[0015] In order to facilitate the delivery of cooling gas and metal particles into the growth cavity, the outer side wall of the growth cavity is provided with a cooling gas inlet communicated with the channel and a metal particle delivery port. The delivery of cooling gas can be used to adjust the temperature of the plasma, prevent the temperature of the plasma through which the metal particles pass from being too high, and prevent the temperature of the gas entering the recovery device and the vacuum system from being too high. In addition, the delivery pipeline serves as a cooling cavity, and through its sufficient length, it is used for naturally cooling the gas generated during work and extracted by the vacuum system during the operation of the device, that is, for cooling the gas heated by the plasma in the working state, and simultaneously serving as a transition channel for the metal particles grown in situ in the plasma to enter the lower end of the centrifugal rotation separation tank unit.

[0016] In order to cool the growth cavity during the operation, the side wall of the growth cavity is provided with a second cooling water circuit, and the outer side wall of the growth cavity is further provided with a second cooling water inlet communicated with the second cooling water circuit and a second cooling water outlet. The first cooling water circuit and the second cooling water circuit can be in the form of a bolt or annular arrangement, etc., to achieve cooling in the circumferential direction; the first cooling water circuit and the second cooling water circuit are both made of stainless steel.

[0017] In order to facilitate the observation of the state of the plasma and the falling state of the metal particles, the plasma generator, the cracking cavity, the growth cavity and the delivery pipeline are sequentially arranged from top to bottom, and an observation cavity is further arranged between the growth cavity and the delivery pipeline, and the side wall of the observation cavity is made of transparent material. In this scheme, the observation cavity is arranged at the lower end of the growth cavity, and quartz glass is preferably used as the side wall. Except that the observation cavity part uses quartz glass, the other cavities are all made of stainless steel, and the connection between the cavities all uses a standard flange interface.

[0018] Since the metal particles are micron-sized and easily adhere to the sidewalls of the recovery device, 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, the bottom outlet of the centrifugal rotary separation tank is provided with a product collection tank, and a sealing isolation valve is provided between the bottom outlet of the centrifugal rotary separation tank and the product collection tank. In this solution, a centrifugal rotary separation tank is used to collect the metal particle powder after the solid coating reaction is completed. The centrifugal action of the centrifugal rotary separation tank is used to separate the metal particles adhering to the sidewalls and drop downward into the product collection tank; in addition, a sealing isolation valve is provided between the centrifugal rotary separation tank unit and the product collection tank. The sealing 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 pre-production preparation time required for the next production / experiment, and prevent the damage (such as oxidation) caused by air entering the equipment when the equipment is still at high temperature after the reaction is completed to the internal units of the equipment, especially the graphite sleeve, which undoubtedly extends the service life of the various systems of the equipment, especially the vacuum system.

[0019] To further collect 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-absorbing seat for support. The dust collector is set on the outer wall of the centrifugal rotary separation tank and is used to collect metal particles and powder that may adhere to the inner wall of the equipment and the metal filter sleeve after production / experiments are completed; the lower end of the centrifugal rotary separation tank is provided with a shock-absorbing seat, which consists of three legs with an angle of 120 degrees between them, used to support the entire equipment. The legs are provided with elastic buffer devices to prevent vibration damage to the equipment during the operation of the dust collector and vibrator.

[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 rotary 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. 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 pipe. In this solution, a graphite sleeve is provided as an inner layer in the plasma generator, cracking chamber, and growth chamber to prevent the internal temperature from being too high during operation and burning 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 ports are about 3mm away from the inner wall of the graphite sleeve. The thermocouples used for real-time measurement of the temperature changes inside the cracking chamber and the growth chamber during the experiment are inserted into the graphite sleeve through the first temperature measuring port and the second temperature measuring port. In the centrifugal separation tank, 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. The third temperature measuring port set on the top of the centrifugal separation tank is used to measure the temperature of the reaction gas at the tail end of the conveying pipeline. The thermocouple installed in 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 vacuum 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] This solution also features a separate gas supply unit, located outside each cylinder, to supply various process gases to the plasma generator, cracking chamber, and growth chamber. The cooling gas delivered to the plasma generator and cracking chamber is the same medium gas used to deliver the metal particles and powder to the growth chamber via the gas feeder. A float flowmeter or mass flow controller is used in the gas supply unit to precisely control 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 produces chemically active groups;

[0029] 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 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-state 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 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, this design can greatly save the preliminary preparation time required for the next production / experiment, and prevent 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. 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 examples. It should be understood that the following drawings only illustrate certain embodiments of the present invention and should not be considered as limiting the scope. A person of ordinary skill in the art can also derive other relevant drawings based on these drawings without inventive effort. 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 the cracking chamber provided by the present invention;

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

[0039] Markings and corresponding parts names in the accompanying 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, 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 examples and drawings. The exemplary embodiments of the present invention and their descriptions are only used to explain the present invention and are not intended to limit the present invention.

[0042] Example 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 side of the figure is a schematic structural diagram 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 chamber 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 into 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 chamber 3 is connected to a recovery device 6 via a delivery pipe 5 ; the metal particles can enter the recovery device 6 through the channel between the inner cavity of the growth chamber 3 and the inside of the delivery pipe 5 under the action of gravity.

[0050] Compared with the existing technology, solid-state film coating and growth can only be performed on small batches of substrate surfaces. If large batches are 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-state 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 solution, metal particle powder can directly pass through the plasma to complete the in-situ production reaction of the solid-state 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, for introducing a high-frequency DC power supply and generating plasma; the cracking chamber 2 is arranged at the lower end of the plasma generator 1, for cracking the reaction gas to generate chemically active groups; the growth chamber 3 is arranged at the lower end of the cracking chamber 2, for conveying metal particle powder; the lower end of the growth chamber 3 is connected to the recovery device 6 through a conveying pipe 5, for recovering the reaction product; wherein, when the metal particle powder is conveyed into the growth chamber 3, the channel inside the growth chamber 3 is already filled with plasma, and the metal particle powder conveyed into the growth chamber 3 can directly enter the plasma. 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, downward inclined or downward bent, so that the metal particles can fall freely 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 fed into the plasma, so that the in-situ reaction time reaches the millisecond level, reducing the time for the solid film growth to be completed on the surface of the metal particle powder; not only shortening the reaction time, but also improving 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] 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, both connected to the channel. The delivery of cooling gas can be used to regulate the plasma temperature, preventing the plasma temperature from being too high after the metal particles pass through, and preventing the gas from being too high after entering the recovery device 6 and the vacuum system. Furthermore, the delivery pipe 5 acts as a cooling chamber, providing sufficient length to naturally cool the gas generated during operation and extracted from the vacuum system during operation. This cooling is used to cool the gas heated by the plasma during operation, and also serves as a transition channel for the metal particles, which have completed in-situ growth in the plasma, to enter the lower end of the centrifugal separation tank unit.

[0054] To cool the growth chamber 3 during operation, a second cooling water circuit is provided in the sidewalls of the growth chamber 3. The outer wall of the growth chamber 3 also includes a second cooling water inlet 15-1 and a second cooling water outlet 15-2, which communicate with the second cooling water circuit. Both the first and second cooling water circuits can be bolted or arranged in a circular pattern to achieve circumferential cooling. Both the first and second cooling water circuits are constructed of stainless steel.

[0055] To facilitate observation of the plasma state and the falling state of the metal particles, the plasma generator 1, cracking chamber 2, growth chamber 3, and delivery pipe 5 are arranged sequentially from top to bottom. An observation chamber 4 is also located between the growth chamber 3 and the delivery pipe 5, and its sidewalls are made of transparent material. In this embodiment, the observation chamber 4 is located at the lower end of the growth chamber 3 and is preferably made of quartz glass. Except for the observation chamber 4, which is made of quartz glass, all other chambers are made of stainless steel, and the connections between the chambers are all made of standard flange interfaces.

[0056] Since the metal particles are at 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, 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. In this solution, a centrifugal rotating separation tank is used to collect the metal particle powder after the solid-state 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 prevent the air from entering the equipment when the inside of the equipment is still at 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 metal particles and powder that may adhere to the inner wall of the equipment and the metal filter sleeve, a dust collecting vibrator 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-absorbing seat 9 for support. The dust collecting vibrator 8 is set on the outer wall of the centrifugal rotary separation tank and is used to collect metal particles and powder that may adhere to the inner wall of the equipment and the metal filter sleeve after production / experiments are completed; the lower end of the centrifugal rotary separation tank is provided with a shock-absorbing seat 9, which is composed of three legs with an angle of 120 degrees between them, and is used to support the entire equipment. Elastic buffer devices are provided at the legs to prevent vibration damage to the equipment during the period when the dust collecting vibrator 8 is turned on.

[0058] In order to indirectly measure the inner wall temperature of the pyrolysis chamber 2 and the growth chamber 3 and the gas temperature at the connection between the centrifugal rotary separation tank and the delivery pipeline 5, and accurately control the reaction temperature, 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. 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 solution, a graphite sleeve is provided as an inner layer 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 burning the cooling water channel; channels for placing thermocouples are drilled on the graphite sleeve inside the cracking chamber 2 and the growth chamber 3, namely the first temperature measuring port 12 and the second temperature measuring port 16, but the graphite sleeve is not drilled through. The channel ports are 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, in order 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 pipe 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 pipe 5. Taking into account 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] To evacuate the interior of the device, test the vacuum level before and after operation, and prevent metal particles from entering the vacuum system, the top of the recovery device 6 is also equipped with a vacuum port 20 that communicates with the interior and a vacuum measurement port 19. The vacuum port 20 is used to connect to the vacuum system, and the recovery device 6 is connected to the vacuum port 20 via a micron-grade metal filter sleeve.

[0062] This solution also includes a gas supply unit 21, located outside each cylinder, for supplying various process gases to the plasma generator 1, cracking chamber 2, and growth chamber 3. This independent gas supply unit 21 supplies the same cooling gas to the plasma generator 1 and cracking chamber 2 as the gas used to deliver the metal particles and powder to the growth chamber 3 via the gas feeder. A float flowmeter or mass flow controller is used in the gas supply unit 21 to precisely control the gas flow.

[0063] Example 2:

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

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

[0066] Then, the gas supply unit 21 is turned on and the gas supply unit 21 is 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 pressure, the vacuum system needs to be used to control the internal vacuum of the device to keep it stable 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] Adjust the gas supply unit 21 again, and use the gas feeder to transport the metal particle powder to the plasma in the growth chamber 3 through the metal particle delivery port 14. The metal particles pass through the plasma and complete the surface solid film in situ growth reaction in a very short time. Then, they freely fall 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 collecting vibrator 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) are 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 into 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; and simultaneously, 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 interior 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) communicating with 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 communicated with 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 delivery pipe (5) are arranged in sequence from top to bottom; an observation chamber (4) is further provided between the growth chamber (3) and the delivery pipe (5); and the side wall of the observation chamber (4) is made of a 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 sealing 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 supporting 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 delivery pipe (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 pumping port (20) and a vacuum measuring port (19) that are communicated with the interior. The vacuum pumping port (20) is used to be connected to a vacuum system, and the recovery device (6) is connected to the vacuum pumping 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 Pa vacuum state; 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; The metal particles then enter the recovery device (6) through the conveying pipe (5) under the action of gravity for recovery.

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