Plasma-coated carbon-based coating and thin film forming method thereof

Abstract

The invention relates to a plasma-coated carbon-based coating and a thin film forming method thereof. The device for plasma coating of the carbon-based coating comprises a carbon-based polymer coating module and an atmospheric pressure plasma generation assembly. The carbon-based polymer coating module can atomize polymer liquid; the atmospheric pressure plasma generation assembly is an atmospheric pressure plasma jet device, and the distance between a jet nozzle of the atmospheric pressure plasma generation assembly and an atomization outlet of the carbon-based polymer coating module is 5-50 mm. Compared with the prior art, the atmospheric pressure plasma device and the atomization coating module are combined, the generated plasma and the atomized carbon-based polymer coating are subjected to contact reaction, active particles and atomized polymer particles interact, and the atomized polymer particles can be deposited on the surface in a smaller size; therefore, the thickness of the formed film is obviously reduced within the same deposition time, the coating thickness of the coating and the film is controlled, and the overall performance of the coating and the film is improved.

Description

Technical Field

[0001] The present invention belongs to the field of surface treatment of electronic components, and particularly relates to a method for coating a carbon-based polymer coating and forming a thin film thereof by using plasma technology. Background Art

[0002] In order to improve the surface performance of a substrate and enhance the usage effect of a product, a material with specific functions can be attached to the surface of the material by using a coating technology. With the increasing complexity of the substrate structure and the enhanced selectivity of product usage, the requirements for coating are also continuously improving. For application fields such as electronic components, coating accuracy represented by thickness and width has become a set of key indicators of process technology. Due to the complexity of fluid control, when the coating accuracy is high, the existing technologies can no longer meet the requirements. Therefore, developing a precise coating technology has important practical application value. Chinese invention patent CN113546808A, a dispensing structure and method for nano metal paste, provides a dispensing device, which provides another precise dispensing head and can realize continuous automatic replenishing of glue. Chinese invention patent CN116273758A, a high-precision array contact type fluid dispensing method, adopts an array of dispensing ports corresponding to a workpiece moving at a high frequency and a short distance in the vertical direction to perform simultaneous dispensing operations on multiple glue dots, greatly improving the overall dispensing efficiency. Chinese invention patent CN105750156A, a precise automatic dispensing device and method, also provides a precise automatic dispensing device, which introduces three-axis drive and a three-dimensional joystick, improving the automation degree of the dispensing device; when replacing the spray needle of the dispensing device, a visual positioning and first glue drop calibration method is adopted, which can quickly calibrate and realize precise positioning dispensing. However, only the automation of the dispensing process has been improved in the above patents, and the thickness of the glue coating has not been controlled. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a method for enhancing the coating accuracy of a carbon-based polymer coating by using atmospheric pressure plasma technology. Through the interaction between the active particles in the plasma and the coating glue, the thickness of the formed thin film is significantly reduced, realizing high-precision coating and thin film formation, and being more suitable for the surface treatment of high-frequency electronic components.

[0004] One aspect of the present invention provides a device for improving the coating accuracy of a carbon-based polymer coating, the device comprising a carbon-based polymer coating module and an atmospheric pressure plasma generating assembly;

[0005] The carbon-based polymer coating module can atomize the carbon-based polymer liquid;

[0006] The atmospheric pressure plasma generation component described above is an atmospheric pressure plasma jet device, and the distance between the jet nozzle of the atmospheric pressure plasma generation component and the atomization outlet of the polymer coating module is 5 mm - 50 mm. For example, 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, 45 mm, 50 mm.

[0007] Further, the device further includes an automated control module, which controls the opening and closing of the atmospheric pressure plasma generation component and the polymer coating module, and can first turn on the atmospheric pressure plasma generation component, turn on the polymer coating module after the discharge is stable, and turn off the atmospheric pressure plasma generation component 1 - 50 s after the polymer coating module is turned off.

[0008] Further, the automated control module can control the distance between the jet nozzle of the atmospheric pressure plasma generation component and the atomization outlet of the polymer coating module.

[0009] Further, the polymer coating module can control the degree of polymer atomization through pressure.

[0010] Further, the discharge gas of the atmospheric pressure plasma generation component described above is one or more of air, argon, and nitrogen.

[0011] Further, the flow rate of the discharge gas of the atmospheric pressure plasma generation component is 0.01 L / min - 1 L / min. For example, 0.01 L / min, 0.05 L / min, 0.1 L / min, 0.3 L / min, 0.5 L / min, 1 L / min.

[0012] Further, the carbon-based polymer is selected from at least one of polyurethane, epoxy resin, and acrylic resin.

[0013] One aspect of the present invention provides a method for improving the coating accuracy of a carbon-based polymer coating. Using the device for improving the coating accuracy of a carbon-based polymer coating described above, the specific steps are as follows:

[0014] S1) Adjust the distance between the jet nozzle of the atmospheric pressure plasma generation component and the atomization outlet of the carbon-based polymer coating module;

[0015] S2) Start the atmospheric pressure plasma discharge, and after 2 - 10 s, when the discharge is stable;

[0016] S3) Start the carbon-based polymer coating module, atomize and spray the carbon-based polymer coating for coating;

[0017] S4) After the coating is completed, close the atomizing nozzle, and then turn off the atmospheric pressure plasma discharge.

[0018] Further, in S1), the distance between the jet nozzle of the atmospheric pressure plasma generation component and the atomization outlet of the carbon-based polymer coating module is 5 - 50 mm. Further, in S2), the discharge gas for the atmospheric pressure plasma discharge is one or more of air, argon, and nitrogen.

[0019] Further, in S3), the pressure for atomizing the carbon-based polymer coating is 0.01 MPa - 5 MPa. For example, it can be 0.1 MPa, 0.5 MPa, 1 MPa, 2 MPa, 3 MPa, 4 MPa, 5 MPa.

[0020] Further, the method for improving the coating accuracy of the carbon-based polymer coating is a method of reducing the coating thickness of the carbon-based polymer coating by more than 0.4 μm.

[0021] Further, the method for improving the coating accuracy of the carbon-based polymer coating is a method of reducing the coating thickness of the polymer coating by 0.4 μm - 5 μm.

[0022] Another aspect of the present invention provides a coating prepared by the above method. The average thickness of the coating is 10 μm or less, preferably 0.9 - 10 μm. For example, 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm.

[0023] Another aspect of the present invention provides a method for reducing the coating thickness of the carbon-based polymer coating. The method uses the above device for improving the coating accuracy of the polymer coating and makes the plasma discharge stably before starting the spray coating of the polymer coating.

[0024] Beneficial Effects

[0025] Compared with the prior art, the present invention combines the atmospheric pressure plasma device with the atomization coating module, makes the generated plasma contact and react with the atomized polymer coating, and the active particles interact with the atomized polymer particles, so that the atomized polymer particles can be deposited on the surface with a smaller size, thereby significantly reducing the thickness of the formed film within the same deposition time, realizing the control of the coating and film coating thickness, and improving the overall performance of the coating and film. Description of the Drawings

[0026] Figure 1 Optical microscope photos of the coatings and films obtained by using the conventional atomization coating method.

[0027] Figure 2 Optical microscope photos of the coatings and films obtained by using the method of the present invention. Detailed Embodiments

[0028] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and understandable, the following will give a detailed description of the specific embodiments of the present invention, but it should not be construed as a limitation on the implementable scope of the present invention. In the technical solution of the present invention, the discharge power of the plasma is not limited because those skilled in the art can adjust the discharge power according to the generating device, gas and flow rate, etc., and only need to ensure that the polymer particles are atomized by the plasma. At the same time, if it is necessary to enhance the chemical reaction, active gases such as oxygen or water vapor can also be added to the discharge gas. In addition, on the basis of the present invention, the generation method, generation pressure and other conditions of the plasma can be adjusted as needed. The technical problem solved by the present invention is to reduce the thickness of the coating and the formed film of the existing electronic components, add an atmospheric pressure plasma component to the atomization coating module, and keep a certain distance from the atomization coating component. This design not only ensures the normal progress of atomization coating, but also ensures the interaction between the active particles in the plasma and the atomized particles. Under this action, the active particles in the plasma will have physical and chemical reactions such as collision and dissociation with the atomized particles, significantly reducing the size of the atomized particles, and thus significantly reducing the thickness of the coating and the formed film.

[0029] Formation of a polymer film with an average thickness of 10 μm in Example 1

[0030] Load the commercially available polyurethane solution into the fluid control device, adjust the distance between the atmospheric pressure plasma nozzle and the atomizing nozzle to 20 mm, introduce compressed air at a flow rate of 1 L / min and start the atmospheric pressure plasma discharge. After 5 s, atomize the polyurethane solution at a pressure of 0.02 MPa and deposit it on the circuit board to form a polymer film. According to the film thickness test results, the average thickness of the prepared polymer film is 10 μm, as Figure 2 shown.

[0031] Formation of a polymer film with an average thickness of 14 μm in Comparative Example 1

[0032] Load the commercially available polyurethane solution into the fluid control device, atomize the polyurethane solution at a pressure of 0.2 MPa, and deposit it on the circuit board to form a polymer film. According to the film thickness test results, the average thickness of the prepared polymer film is 13 μm, as Figure 1 shown.

[0033] Formation of a polymer film with an average thickness of 0.9 μm in Example 2

[0034] Load the commercially available polyurethane solution into the fluid control device, adjust the distance between the atmospheric pressure plasma nozzle and the atomizing nozzle to 10 mm, introduce argon at a flow rate of 0.01 L / min and initiate atmospheric pressure plasma discharge. After 2 s, atomize the polyurethane solution at a pressure of 0.3 MPa and deposit it onto the circuit board to form a polymer film. According to the film thickness test results, the average thickness of the prepared polymer film is 0.9 μm

[0035] Formation of a polymer film with an average thickness of 1.3 μm in Comparative Example 2

[0036] Load the commercially available polyurethane solution into the fluid control device, atomize the polyurethane solution at a pressure of 0.2 MPa and deposit it onto the circuit board to form a polymer film. According to the film thickness test results, the average thickness of the prepared polymer film is 1.3 μm, as Figure 1 shown

[0037] From the comparison between Example 1 and Comparative Example 1, and between Example 2 and Comparative Example 2, it can be seen that the method of the present invention adds plasma treatment on the basis of the original atomized spraying of the carbon-based polymer coating. The obtained coating has a thickness reduction of at least 20% compared to the original coating. For the polyurethane polymer film, a thickness of 0.9 μm is achieved. Comparing Figure 1 and Figure 2 it can be seen that the film of the present invention is thinner, can transmit light, and has a uniform thickness

[0038] Formation of a polymer film with an average thickness of 3 μm in Example 3

[0039] Load the commercially available epoxy resin solution into the fluid control device, adjust the distance between the atmospheric pressure plasma nozzle and the atomizing nozzle to 12 mm, introduce nitrogen at a flow rate of 0.2 L / min and initiate atmospheric pressure plasma discharge. After 8 s, atomize the epoxy resin solution at a pressure of 0.1 MPa and deposit it onto the circuit board to form a film. According to the film thickness test results, the average thickness of the prepared film is 3 μm

[0040] Formation of a polymer film with an average thickness of 5 μm in Example 4

[0041] Load the commercially available acrylic resin solution into the fluid control device, adjust the distance between the atmospheric pressure plasma nozzle and the atomizing nozzle to 18 mm, introduce air at a flow rate of 0.3 L / min and initiate atmospheric pressure plasma discharge. After 10 s, atomize the acrylic resin solution at a pressure of 0.1 MPa and deposit it onto the circuit board to form a polymer film. According to the film thickness test results, the average thickness of the prepared film is 5 μm

[0042] Verified by multiple embodiments of the present invention, it can be seen that the devices and methods of the present invention have a wide range of applications. As long as the carbon-based polymer coating can be atomized by high-pressure means, the method of the present invention can be used, that is, by performing plasma discharge while atomizing the carbon-based polymer. When the plasma spraying device and the atomizing device maintain a certain distance, the thickness of the carbon-based polymer coating can be reduced. The method of the present invention is simple, and at the same time, the existing atomizing spraying device can be improved according to the method of the present invention to meet more refined coating requirements.

Claims

1. An apparatus for improving the coating accuracy of a carbon-based polymer coating, characterized in that, the apparatus includes a carbon-based polymer coating module and an atmospheric pressure plasma generation component; the carbon-based polymer coating module can atomize the carbon-based polymer liquid; the atmospheric pressure plasma generation component is an atmospheric pressure plasma jet device, and the distance between the jet nozzle of the atmospheric pressure plasma generation component and the atomization outlet of the carbon-based polymer coating module is 5 mm - 50 mm.

2. The apparatus according to claim 1, characterized in that, the apparatus further includes an automatic control module, and the automatic control module controls the opening and closing of the atmospheric pressure plasma generation component and the carbon-based polymer coating module, and can first turn on the atmospheric pressure plasma generation component, turn on the carbon-based polymer coating module after the discharge is stable, and turn off the atmospheric pressure plasma generation component 1 - 50 s after the carbon-based polymer coating module is turned off.

3. The apparatus according to claim 1, characterized in that, the automatic control module can control the distance between the jet nozzle of the atmospheric pressure plasma generation component and the atomization outlet of the carbon-based polymer coating module; preferably, the carbon-based polymer coating module can control the atomization degree of the carbon-based polymer by pressure.

4. The apparatus according to claim 1, characterized in that, the flow rate of the discharge gas of the atmospheric pressure plasma generation component is 0.01 L - 1 L / min; preferably, the discharge gas of the atmospheric pressure plasma generation component is one or more of air, argon, and nitrogen.

5. The apparatus according to claim 1, characterized in that, the carbon-based polymer is selected from at least one of polyurethane, epoxy resin, and acrylic resin.

6. A method for improving the coating accuracy of a carbon-based polymer coating, characterized in that, the apparatus for improving the coating accuracy of a carbon-based polymer coating according to any one of claims 1 - 5 is used for coating the carbon-based polymer coating, and the specific steps are as follows: S1) Adjust the distance between the jet nozzle of the atmospheric pressure plasma generation component and the atomization outlet of the carbon-based polymer coating module; S2) Start the atmospheric pressure plasma discharge, and after 2 - 10 s, the discharge is stable; S3) Start the carbon-based polymer coating module, atomize and spray the carbon-based polymer coating for coating; S4) After the coating is completed, close the atomizing nozzle, and then turn off the atmospheric pressure plasma discharge; preferably, in S1), the distance between the jet nozzle of the atmospheric pressure plasma generation component and the atomization outlet of the carbon-based polymer coating module is 5 - 50 mm; preferably, in S2), the discharge gas for the atmospheric pressure plasma discharge is one or more of air, argon, and nitrogen.

7. The method according to claim 6, characterized in that, in S3), the pressure for atomizing the carbon-based polymer coating is 0.01 - 5 MPa.

8. The method according to claim 6, characterized in that, the method for improving the coating accuracy of the carbon-based polymer coating is a method for reducing the coating thickness of the carbon-based polymer coating by more than 0.4 μm; preferably, the method for improving the coating accuracy of the carbon-based polymer coating is a method for reducing the coating thickness of the carbon-based polymer coating by 0.4 μm - 5 μm.

9. A coating obtained by the method according to any one of claims 6-8, wherein the average thickness of the coating is 10 μm or less; Preferably, it is 0.9 μm - 10 μm.

10. A method capable of reducing the coating thickness of a carbon-based polymer coating, the method using the device for improving the coating accuracy of a carbon-based polymer coating according to any one of claims 1-5, and stabilizing the plasma discharge before starting the spray coating of the carbon-based polymer coating.

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