A vacuum plasma processing device and a control method thereof

Abstract

The present invention relates to plasma surface treatment technology, and more particularly to a vacuum plasma treatment device and a control method thereof. The vacuum plasma treatment device comprises a frame, a vacuum chamber mounted on the frame, and a control assembly. The vacuum chamber is provided with a sealed door with a sealing strip disposed on the side of the sealed door facing the vacuum chamber. The vacuum chamber is provided with a placement rack and a plasma generating assembly, which is configured to generate plasma from a selected gas introduced therein and includes an ionization assembly and a gas supply assembly. A vacuum assembly is disposed on the back of the vacuum chamber and is configured to create a vacuum environment within the vacuum chamber. The control assembly is configured to control the operation of the plasma generating assembly and the vacuum assembly. The provision of the sealed door and vacuum assembly in the present invention achieves a stable vacuum environment, and the plasma generated by the ionization assembly and the gas supply assembly is used to perform surface treatment on the product.

Description

Technical Field

[0001] The present invention belongs to the field of plasma surface treatment technology, and in particular relates to a vacuum plasma treatment device and a control method thereof. Background Art

[0002] Currently, dispensing, inkjet printing, bonding and other processes have made great progress in improving product performance, but still face the problem of unreliable and unstable quality.

[0003] The main reason for this is that some products have smooth surfaces and poor adsorption. Plasma treatment of these products can significantly improve their surface adsorption, enabling glue dispensing, inkjet printing, and bonding to achieve the desired results. Compared to conventional surface treatment methods, vacuum plasma treatment can reach even the smallest gaps and deep holes in products, unconstrained by the product's structure, and provides a more thorough treatment.

[0004] When plasma is applied to a product's surface, it's crucial to prevent environmental impurities from interacting with the plasma and causing uncontrolled effects on the product, or to prevent impurities from consuming the plasma. Therefore, a clean environment is essential for plasma treatment. Providing a stable and clean environment for the product to improve the quality of plasma treatment is a crucial issue. Summary of the Invention

[0005] An object of the embodiments of the present invention is to provide a vacuum plasma processing apparatus, aiming to solve the problem of how to provide a stable and clean environment for products so as to improve the quality of plasma processing.

[0006] The embodiment of the present invention is implemented as follows: a vacuum plasma processing device, the vacuum plasma processing device includes a frame, a vacuum chamber arranged on the frame, and a control component;

[0007] The vacuum chamber is provided with a sealed door, a sealing strip is provided on the side of the sealed door facing the vacuum chamber, a placement rack and a plasma generating assembly are provided in the vacuum chamber, the plasma generating assembly is used to form plasma from the selected gas introduced, the plasma generating assembly includes an ionization assembly and a gas supply assembly; a vacuum assembly is provided on the back side of the vacuum chamber, the vacuum assembly is used to form a vacuum environment in the vacuum chamber;

[0008] The control component is used for controlling the operation of the plasma generating component and the vacuum component.

[0009] Another object of an embodiment of the present invention is to provide a control method for a vacuum plasma processing apparatus, which is applied to the vacuum plasma processing apparatus as described in the present invention. The control method for the vacuum plasma processing apparatus includes:

[0010] Place the product to be treated in the vacuum chamber and close the sealing door;

[0011] Controlling the vacuum pump to evacuate the vacuum chamber;

[0012] When the vacuum degree in the vacuum chamber reaches the set value P0, the selected gas is introduced into the vacuum chamber and the radio frequency power is turned on to ionize the product;

[0013] After the ionization treatment is completed, the vacuum pump is turned off and nitrogen is introduced into the vacuum chamber;

[0014] When the set time is reached, the balance air inlet is opened to balance the air pressure inside and outside the vacuum chamber.

[0015] The vacuum plasma treatment apparatus provided by the embodiments of the present invention utilizes a sealed door to create a stable vacuum environment within the vacuum chamber. A plasma generating assembly is also provided to energize the selected gas introduced into a plasma. This invention utilizes plasma to treat the surface of a product, improving its surface properties and enhancing its surface adsorption, facilitating subsequent gluing, inkjet printing, or bonding. The treatment method of the present invention is unaffected by small gaps and holes in the product, resulting in a more thorough treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A three-dimensional structural diagram of a vacuum plasma processing device provided in an embodiment of the present invention;

[0017] Figure 2 A diagram showing the internal structure of a vacuum plasma processing device provided by an embodiment of the present invention;

[0018] Figure 3 This is the internal structure diagram of the vacuum chamber;

[0019] Figure 4 This is the back structure diagram of the vacuum chamber;

[0020] Figure 5 This is a control structure diagram of a vacuum plasma processing device provided by an embodiment of the present invention.

[0021] In the attached figure: 1. Frame; 2. Vacuum chamber; 3. Button; 4. Touch screen; 5. Warning light; 6. Vacuum pump; 7. Control box; 8. RF power supply; 9. Insulating connector; 10. Discharge electrode plate; 11. Product placement plate; 12. L-shaped connector; 13. Insulating part; 14. Strip copper plate; 15. RF power supply discharge electrode; 16. Insulating ceramic; 17. Induction switch; 18. Vacuum electrode; 19. Vacuum pipe valve; 20. Second solenoid valve; 21. First solenoid valve; 22. Metal air inlet pipe; 23. Solenoid control valve; 24. Bellows; 25. Argon flow controller; 26. Solenoid pilot control valve; 27. Thermometer; 28. Muffler; 29. ​​Vacuum gauge; 30. Hinge. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0023] The specific implementation of the present invention is described in detail below with reference to specific embodiments.

[0024] like Figure 1-4 As shown, an embodiment of the present invention provides a vacuum plasma processing device, comprising a frame 1, a vacuum chamber 2 arranged on the frame 1, and a control component;

[0025] The vacuum chamber 2 is provided with a sealed door, and a sealing strip is provided on the side of the sealed door facing the vacuum chamber 2. A placement rack and a plasma generating assembly are provided in the vacuum chamber 2. The plasma generating assembly is used to form plasma from the selected gas introduced, and the plasma generating assembly includes an ionization assembly and a gas supply assembly. A vacuum assembly is provided on the back side of the vacuum chamber 2, and the vacuum assembly is used to form a vacuum environment in the vacuum chamber 2.

[0026] The control component is used for controlling the operation of the plasma generating component and the vacuum component.

[0027] In this embodiment, the vacuum chamber 2 is generally in the shape of a cube or a rectangular parallelepiped, with a hollow interior. The sealed door is connected to the vacuum chamber 2 by a hinge 30, and a double-layer sealing strip is provided on the sealed door. When the sealed door is closed, the interior of the vacuum chamber 2 is relatively isolated from the outside. In this embodiment, the vacuum chamber 2 is provided on a frame 1. For the specific form of the frame 1, please refer to the structure shown in the accompanying drawings of the present invention. The specific structural form of the frame 1 does not affect the realization of the functions of the present invention, and the present invention does not impose too many restrictions on this. Optionally, the frame 1 is also provided with a touch screen display 4 and a warning light 5. A button 3 is provided next to the touch screen display 4 to assist operation. A control box 7 is provided at the bottom of the frame 1, and a vacuum pump 6 is provided above the control box 7.

[0028] In this embodiment, the plasma generating assembly includes an ionization assembly and a gas supply assembly. The ionization assembly ionizes a selected gas provided by the gas supply assembly to generate plasma. In this embodiment, the selected gas may be a single ionizable gas such as argon. Of course, a mixed gas may also be used as needed, but a single gas is preferably used.

[0029] In this embodiment, the control components include a controller (single chip microcomputer or PLC, etc.) and controlled valves, air pumps, vacuum pumps 6, sensors and various instruments, etc. For details, please refer to Figure 5 shown.

[0030] The vacuum plasma treatment apparatus provided in an embodiment of the present invention utilizes a sealed door to create a stable vacuum environment within the vacuum chamber 2. A plasma generating assembly is also provided to energize the selected gas introduced into a plasma. This invention utilizes plasma to treat the surface of a product, improving its surface properties and enhancing its surface adsorption, facilitating subsequent gluing, inkjet printing, or bonding. The treatment method of the present invention is unaffected by small gaps and holes in the product, resulting in a more thorough treatment.

[0031] As an optional embodiment of the present invention, the ionization assembly includes a vacuum electrode 18 arranged on the back side of the vacuum chamber 2, wherein one end of the vacuum electrode 18 away from the vacuum chamber 2 is connected to the RF power supply 8, and the other end is connected to the RF power supply discharge electrode 15 arranged in the vacuum chamber 2.

[0032] In this embodiment, the periphery of the vacuum electrode 18 connected to the vacuum chamber 2 is insulated from the electric core inside the vacuum electrode 18. The vacuum electrode 18 is the main component for exciting argon gas to generate ions. Its principle and structure can refer to the existing technology. The specific structure and principle of the vacuum electrode 18 will not be elaborated in the present invention.

[0033] As an optional embodiment of the present invention, the ionization assembly further includes a strip copper plate 14, a discharge electrode plate 10 and a radio frequency power supply discharge electrode 15 arranged in the vacuum chamber 2;

[0034] The strip copper plate 14 is arranged on the rear side of the inner wall of the vacuum chamber 2 in an upper and lower arrangement. A plurality of L-shaped connectors 12 are provided at equal intervals above and below the strip copper plate 14. One end of the L-shaped connector 12 is overlapped on the strip copper plate 14, and the other end is overlapped on the discharge electrode plate 10.

[0035] The discharge electrode plates 10 are provided with a plurality of pieces, which are arranged horizontally in the vacuum chamber 2 at equal intervals, and each of the discharge electrode plates 10 is provided with a product placement plate 11;

[0036] The radio frequency power source passes through the middle of the strip copper plate 14 and extends into the vacuum chamber 2 .

[0037] In this embodiment, a strip copper plate 14 is extended and connected to multiple discharge electrodes 10 via an L-shaped connector 12. The number of RF power supply discharge electrodes 15 is the same as the number of discharge electrodes 10. One RF power supply discharge electrode 15 and one discharge electrode 10 form an ionization group, and each ionization group can ionize and excite a selected gas. In this embodiment, through this arrangement, each ionization group can ionize a selected gas, achieving multi-point ionization, increasing the proportion of ionized selected gases dispersed within the vacuum chamber 2, improving the utilization rate of the selected gases, and making the plasma generated after ionization more evenly dispersed within the vacuum chamber 2, thereby improving the uniformity of the surface treatment.

[0038] In this embodiment, the discharge electrode 10 at the bottom is fixed to the vacuum chamber 2 through an insulating connector 9; the strip copper plate 14 is connected and fixed to the rear wall of the vacuum chamber through an insulating ceramic 16; the RF power supply discharge electrode 15 is insulated from the strip copper plate 14 by an insulating member 13.

[0039] As an optional embodiment of the present invention, the gas supply assembly includes a first solenoid valve 21 and a second solenoid valve 20 provided on the back of the vacuum chamber 2;

[0040] The first solenoid valve 21 is used for on-off control of argon gas. The inlet of the first solenoid valve 21 is connected to the inlet of the argon flow controller 25. The outlet of the first solenoid valve 21 leads to the vacuum chamber 2. The inlet of the argon flow controller 25 is connected to the argon gas supply port.

[0041] The second solenoid valve 20 is used for on-off control of nitrogen. The inlet of the second solenoid valve 20 is connected to the nitrogen supply port, and the outlet of the second solenoid valve 20 is connected to the vacuum chamber 2.

[0042] In this embodiment, through the cooperation of the first solenoid valve 21 and the second solenoid valve 20, on the one hand, argon gas can be introduced into the vacuum chamber 2 for the ionization process, and on the other hand, nitrogen gas can be introduced into the vacuum chamber 2 for the atmosphere protection in the vacuum chamber 2. In this embodiment, the selected gas is argon gas.

[0043] As an optional embodiment of the present invention, the vacuum assembly includes a vacuum pipe valve 19 provided on the back of the vacuum chamber 2, one end of the vacuum pipe valve 19 is connected to the vacuum pump 6 via a bellows 24, and the other end is in communication with the interior of the vacuum chamber 2;

[0044] The vacuum pipe valve 19 is controlled to open or close by the electromagnetic control valve 23 .

[0045] In this embodiment, the provision of a vacuum evacuation pipe and a vacuum pump 6 facilitates the formation and maintenance of a vacuum within the vacuum chamber 2, thereby enabling ionization to occur in a stable environment and promptly removing impurities generated during ionization or the ionization process. In this embodiment, a first solenoid valve 21 introduces argon gas into the vacuum chamber 2 via a metal inlet pipe 22.

[0046] As an optional embodiment of the present invention, the vacuum assembly further includes an electromagnetic pilot control valve 26 provided on the back of the vacuum chamber 2, and the electromagnetic pilot control valve 26 is used to control the opening or closing of the balance air inlet;

[0047] A muffler 28 is connected between the electromagnetic pilot control valve 26 and the vacuum chamber 2 , and the muffler 28 is used to reduce noise generated by airflow.

[0048] In this embodiment, the noise generated by the rapid flow of gas can be reduced by providing the muffler 28 .

[0049] As an optional embodiment of the present invention, the vacuum plasma processing apparatus further includes a detection component, which includes an induction switch 17, a vacuum gauge 29 and a thermometer 27;

[0050] The induction switch 17 is provided on the contact surface between the vacuum chamber 2 and the sealing door, and is used to detect the switch state of the sealing door;

[0051] The vacuum gauge 29 penetrates the vacuum chamber 2 from the back side of the vacuum chamber 2 to detect the vacuum degree in the vacuum chamber 2;

[0052] The thermometer 27 penetrates into the vacuum chamber 2 from the back side of the vacuum chamber 2 to detect the temperature inside the vacuum chamber 2 .

[0053] In this embodiment, the detection component is provided to detect the state in the vacuum chamber 2 in real time, thereby facilitating the control of the vacuum chamber 2 .

[0054] An embodiment of the present invention further provides a control method for a vacuum plasma processing apparatus, which is applied to the vacuum plasma processing apparatus according to any embodiment of the present invention. The control method for the vacuum plasma processing apparatus includes:

[0055] Place the product to be processed in the vacuum chamber 2 and close the sealing door;

[0056] Controlling the vacuum pump 6 to evacuate the vacuum chamber 2;

[0057] When the vacuum degree in the vacuum chamber 2 reaches the set value P0, the selected gas is introduced into the vacuum chamber 2 and the radio frequency power is turned on to ionize the product;

[0058] After the ionization treatment is completed, the vacuum pump 6 is turned off and nitrogen is introduced into the vacuum chamber 2;

[0059] When the set time is reached, the balance air inlet is opened to balance the air pressure inside and outside the vacuum chamber 2.

[0060] In this embodiment, unless otherwise specified, the vacuum level values ​​in the present invention are all negative values, indicating a value below atmospheric pressure. In this embodiment, after the ionization treatment is completed, the vacuum pump 6 is turned off and nitrogen is introduced to provide a protective atmosphere for the product for a set period of time. In this embodiment, the set value P0 can be set as needed and is generally within -0.5 MPa.

[0061] As an optional embodiment of the present invention, the step of introducing the selected gas into the vacuum chamber 2 and turning on the radio frequency power supply to ionize the product includes:

[0062] Turn off the vacuum pump 6 and turn on the RF power supply;

[0063] Continue to introduce the selected gas into the vacuum chamber 2 until the vacuum degree reaches the set value P N , close the selected gas, open the vacuum pump 6 and make the vacuum degree in the vacuum chamber 2 reach P i , repeat this step n times, where P0<P i <P N <0, and P i <P i+1 , i is the ordinal number of this step.

[0064] In this embodiment, the above-mentioned segmented treatment can effectively prevent the selected gas from being quickly drawn away each time, thereby extending the residence time of the selected gas. This segmented treatment method can save the amount of argon gas and enable the plasma to contact the product more fully. n is the set number of repetitions, and n is a positive integer. i <P i+1, that is, controlling the amount of argon introduced each time so that it can be reduced gradually, which can save the use of argon.

[0065] As an optional embodiment of the present invention, the number of repetitions n of the step is determined by the following steps:

[0066] Determine the vacuum degree in vacuum chamber 2 changes from P0 to P N The volume V of the selected gas introduced i ;

[0067] Calculate V i With V i-1 The difference V′ i ;

[0068] If V′ i ≥ΔV′ and |V′ i -V′ i-1 | / V′ i ≤Δ1, then n is equal to the number of repetitions performed plus 2k;

[0069] If V′ i ≥ΔV′ and |V′ i -V′ i-1 | / V′ i >Δ1, or V′ i <ΔV′ and |V i -V′ i-1 | / V′ i >Δ1, then n is equal to the number of repetitions performed plus k;

[0070] If V′ i <ΔV′ and |V′ i -V′ i-1 | / V′ i ≤Δ1, then n is equal to the number of repetitions performed plus 1, and this step is repeated k times, and product processing is not completed;

[0071] Wherein: ΔV′ is the preset volume difference threshold; Δ1 is the preset deviation threshold; and k is the preset repetition base.

[0072] In this embodiment, plasma treatment of the product surface proceeds through three stages. In the first stage, argon consumption is high, but the amount consumed each time is not significantly different. During this stage, the product's uppermost layer is primarily treated. In the second stage, argon consumption is moderate, but the amount consumed each time varies significantly. During this stage, the product's subsurface layer is primarily treated. In the third stage, argon consumption is low, and the amount consumed each time also varies slightly. During this stage, larger impurities or reactive components that remain untreated are further treated. In this embodiment, by setting a repetition base k, the number of treatments can be adjusted in real time based on the results of each treatment. In this embodiment, k can range from 1 to 10, with values ​​such as 2, 4, and 5 being preferred. With this configuration, the argon flow rate does not change immediately when the product treatment transitions from one stage to the next, but is delayed k times. This allows reactions that do not consume plasma to proceed further, while avoiding repeated high-dose treatments and conserving argon gas.

[0073] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A vacuum plasma processing device, characterized in that: The vacuum plasma processing device includes a frame, a vacuum chamber arranged on the frame, and a control component; The vacuum chamber is provided with a sealed door, a sealing strip is provided on the side of the sealed door facing the vacuum chamber, a placement rack and a plasma generating assembly are provided in the vacuum chamber, the plasma generating assembly is used to form plasma from the selected gas introduced, the plasma generating assembly includes an ionization assembly and a gas supply assembly; a vacuum assembly is provided on the back side of the vacuum chamber, the vacuum assembly is used to form a vacuum environment in the vacuum chamber; The control component is used for controlling the operation of the plasma generating component and the vacuum component; The ionization assembly includes a vacuum electrode disposed on the back of the vacuum chamber, wherein one end of the vacuum electrode away from the vacuum chamber is connected to an RF power supply, and the other end is connected to a discharge electrode of the RF power supply disposed in the vacuum chamber; The ionization assembly further comprises a strip copper plate, a discharge electrode plate and a radio frequency power supply discharge electrode arranged in the vacuum chamber; The strip copper plates are arranged on the rear side of the inner wall of the vacuum chamber in an up-and-down arrangement. A plurality of L-shaped connectors are provided at equal intervals above and below the strip copper plates. One end of the L-shaped connector is overlapped with the strip copper plate, and the other end is overlapped with the discharge electrode plate. The discharge electrode plates are provided with a plurality of pieces, which are arranged horizontally in the vacuum chamber at equal intervals, and each of the discharge electrode plates is provided with a product placement plate; The radio frequency power supply extends into the vacuum chamber through the middle of the strip copper plate.

2. The vacuum plasma processing apparatus according to claim 1, wherein: The gas supply assembly includes a first solenoid valve and a second solenoid valve arranged on the back of the vacuum chamber; The first solenoid valve is used for on-off control of argon gas, the inlet of the first solenoid valve is connected to the inlet of the argon flow controller, the outlet of the first solenoid valve leads to the vacuum chamber, and the inlet of the argon flow controller is connected to the argon gas supply port; The second solenoid valve is used for on-off control of nitrogen. The inlet of the second solenoid valve is connected to the nitrogen supply port, and the outlet of the second solenoid valve is connected to the vacuum chamber.

3. The vacuum plasma processing apparatus according to claim 1, wherein: The vacuum assembly includes a vacuum pipe valve provided on the back of the vacuum chamber, one end of the vacuum pipe valve is connected to the vacuum pump through a bellows, and the other end is communicated with the interior of the vacuum chamber; The vacuum pipeline valve is controlled to open or close by an electromagnetic control valve.

4. The vacuum plasma processing apparatus according to claim 3, wherein: The vacuum assembly further includes an electromagnetic pilot control valve disposed on the back of the vacuum chamber, the electromagnetic pilot control valve being used to control the opening or closing of the balanced air inlet; A muffler is connected between the electromagnetic pilot control valve and the vacuum chamber, and the muffler is used to reduce noise generated by airflow.

5. The vacuum plasma processing apparatus according to claim 1, wherein: The vacuum plasma processing device further includes a detection component, which includes an induction switch, a vacuum gauge and a thermometer; The induction switch is arranged on the contact surface between the vacuum chamber and the sealing door, and is used to detect the switch state of the sealing door; The vacuum gauge penetrates into the vacuum chamber from the back side of the vacuum chamber to detect the vacuum degree in the vacuum chamber; The thermometer penetrates into the vacuum chamber from the back side of the vacuum chamber and is used to detect the temperature in the vacuum chamber.

6. A control method for a vacuum plasma processing device, applied to the vacuum plasma processing device according to any one of claims 1 to 5, characterized in that: The control method of the vacuum plasma processing device includes: Place the product to be treated in the vacuum chamber and close the sealing door; Controlling the vacuum pump to evacuate the vacuum chamber; When the vacuum degree in the vacuum chamber reaches the set value P0, the selected gas is introduced into the vacuum chamber and the radio frequency power is turned on to ionize the product; After the ionization treatment is completed, the vacuum pump is turned off and nitrogen is introduced into the vacuum chamber; When the set time is reached, the balance air inlet is opened to balance the air pressure inside and outside the vacuum chamber; The method of introducing the selected gas into the vacuum chamber and turning on the radio frequency power supply to ionize the product includes: Turn off the vacuum pump and turn on the RF power supply; Continue to introduce the selected gas into the vacuum chamber until the vacuum degree reaches the set value P N , close the selected gas, turn on the vacuum pump and make the vacuum degree in the vacuum chamber reach P i , repeat this step n times, where P0<P i <P N <0, and P i <P i+1 , i is the ordinal number of this step; The number of repetitions n of the step is determined by the following steps: Determine the vacuum degree in the vacuum chamber changes from P0 to P N The volume V of the selected gas introduced i ; Calculate V i With V i-1 The difference V i '; If V i ′≥ΔV′ and |V i ′-V′ i-1 | / V i ′≤Δ1, then n is equal to the number of repetitions performed plus 2k; If V i ′≥ΔV′ and |V i ′-V′ i-1 | / V i '>Δ1, or V i ′<ΔV′ and |V i ′-V′ i-1 | / V i '>Δ1, then n is equal to the number of repetitions performed plus k; If V i ′<ΔV′ and |V i ′-V′ i-1 | / V i ′≤Δ1, then n is equal to the number of repetitions performed plus 1, and this step is repeated k times, and the product processing is not completed; Wherein: ΔV′ is the preset volume difference threshold; Δ1 is the preset deviation threshold; and k is the preset repetition base.

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