A pre-treatment manufacturing method of a PCB board before pressing

Abstract

The application discloses a pre-pressing treatment manufacturing method of a PCB, which comprises the following steps: etching treatment is performed on an inner layer plate containing PTFE material to obtain an inner layer plate of the PCB; the inner layer plate after the etching treatment is cleaned and dried to remove liquid on the surface of the inner layer plate, so that the surface of the inner layer plate is kept dry; the inner layer plate after the drying is subjected to plasma treatment, which comprises plasma etching, plasma cleaning and plasma activation; the inner layer plate is sequentially subjected to ion etching, plasma cleaning and plasma activation during the plasma treatment; and the plate after the plasma treatment is transferred to a laminating procedure for subsequent pressing treatment, thereby replacing a traditional sodium naphthalene solution treatment method, effectively improving the surface energy of the PTFE material, improving the bonding strength, avoiding lamination delamination, and compared with the traditional sodium naphthalene treatment method, the method has the characteristics of simple operation, high safety and the like, and can significantly improve the interlayer bonding force of the PTFE material.

Description

Technical Field

[0001] This invention belongs to the field of PCB board technology, and more specifically, it is a method for pre-processing PCB board lamination. Background Technology

[0002] The pre-lamination treatment method for this PCB board is a process that involves etching, drying, and plasma treatment of the inner layers of the PCB board before lamination.

[0003] PTFE is widely used in microwave communication PCBs due to its low dielectric constant and low loss coefficient. However, when used to process multilayer boards, its smooth surface leads to poor adhesion and a risk of delamination, especially when the PTFE content exceeds 80%. Therefore, alternative methods are needed to achieve the desired results. Summary of the Invention

[0004] The problem solved by this invention is:

[0005] When PTFE material is used to process multilayer boards, the relatively smooth surface of PTFE results in poor adhesion, which can easily lead to delamination during the lamination process. This delamination is particularly noticeable when the PTFE content of the board exceeds 80%.

[0006] The objective of this invention can be achieved through the following technical solutions:

[0007] A method for pre-lamination treatment of a PCB board, the specific steps of which are as follows:

[0008] Step 1: Etch the inner layer board containing PTFE material to obtain the inner layer board of the PCB board;

[0009] Step 2: Clean and dry the etched inner layer board to remove the liquid from the surface of the inner layer board and keep the surface of the inner layer board dry.

[0010] Step 3: Perform plasma treatment on the dried inner layer board. The plasma treatment includes plasma etching, plasma cleaning and plasma activation. When performing plasma treatment on the inner layer board, plasma etching, plasma cleaning and plasma activation are performed in sequence.

[0011] Step 4: Transfer the plasma-treated board to the lamination process for subsequent pressing.

[0012] As a further technical solution of the present invention, the interval between the plasma etching, plasma cleaning and plasma activation steps shall not exceed 10 minutes. The plasma etching, plasma cleaning and plasma activation need to be kept at a short interval in order to effectively ensure the plasma treatment effect.

[0013] As a further technical solution of the present invention, the plasma etching is achieved by treating the inner layer board with N2, CF4 and O2 at 80°C for 20-30 minutes to achieve the plasma etching effect. Plasma etching uses plasma to roughen the surface of the board, increase the micro-surface area, and improve the bonding force.

[0014] As a further technical solution of the present invention, the flow rate ratio of N2, CF4 and O2 is 200ml / min: 250ml / min: 1800ml / min.

[0015] As a further technical solution of the present invention, the plasma cleaning is performed by treating the inner layer board with O2 and N2 at 80°C for 10-15 minutes to achieve the plasma cleaning effect. During the plasma etching process, a large amount of residue is easily generated on the surface of the board after being subjected to plasma, which contaminates the board surface. Therefore, plasma cleaning is required before the next step of processing can be carried out.

[0016] As a further technical solution of the present invention, the flow rate ratio of O2 and N2 is 200ml / min:800ml / min.

[0017] As a further technical solution of the present invention, the plasma activation is achieved by treating the inner layer plate with N2 at 80°C for 10 minutes to achieve plasma activation. Plasma activation introduces hydrophilic groups on the PTFE surface through the action of O2 and N2 respectively, transforming the originally hydrophobic PTFE material into a hydrophilic interface, thereby improving the bonding force.

[0018] As a further technical solution of the present invention, the flow rate of N2 is 1000 ml / min.

[0019] As a further technical solution of the present invention, the functions of plasma etching, plasma cleaning, and plasma activation are as follows: Plasma etching uses plasma to roughen the surface of the board, increasing the microscopic surface area and thus improving the bonding force; during the plasma etching process, a large amount of residue is easily generated on the surface of the board after being subjected to plasma, which contaminates the board surface, so plasma cleaning is required before the next step of processing; plasma activation introduces hydrophilic groups on the PTFE surface through the action of O2 and N2 respectively, transforming the originally hydrophobic PTFE material into a hydrophilic interface, thereby improving the bonding force.

[0020] The beneficial effects of this invention are:

[0021] 1. For the pre-lamination treatment of inner layer boards containing PTFE material, the traditional method is to use sodium naphthalene solution. Sodium naphthalene solution is made by dissolving or complexing metallic sodium in active ethers such as tetrahydrofuran, ethylene glycol dimethyl ether and naphthalene. The sodium in the treatment solution can break the CF bond on the PTFE surface, remove F atoms, and defluorinate the surface to form a carbonized layer. However, this treatment method has significant drawbacks: sodium metal is highly reactive, making it prone to safety accidents during storage and production; it generates large amounts of toxic and harmful waste liquid, damaging the environment; the treated board surface must be pressed within a short time, and the adhesion performance of the board surface decreases exponentially over time. By ion-treating the inner layer board containing PTFE material, sequentially completing plasma etching, plasma cleaning, and plasma activation, the surface of the board can be roughened, increasing the microscopic surface area and improving the bonding strength. This replaces the traditional sodium naphthalene solution treatment method, effectively improving its safety, reducing environmental pollution, and enhancing the pressing effect of the board. The plasma treatment method is simple, safe, and easy to operate, and does not generate a large amount of waste, which has significant benefits for safe production and environmental protection.

[0022] 2. The plasma treatment method involves first using plasma etching to roughen the surface of the board, increasing the microscopic surface area and improving adhesion. Then, plasma cleaning removes residue generated during the plasma etching process. Since a large amount of residue easily accumulates on the board surface after plasma treatment, contaminating the surface, plasma cleaning is necessary before proceeding to the next step. Finally, plasma activation introduces hydrophilic groups into the PTFE surface through the action of O2 and N2, transforming the originally hydrophobic PTFE material into a hydrophilic interface, further enhancing adhesion. These three steps respectively increase surface area, clean the board surface, and improve the surface energy, thus improving the board's adhesion performance from three dimensions. Compared to traditional sodium naphthalene treatment methods, this method has significant advantages in terms of technology, economy, and social benefits. Attached Figure Description

[0023] The invention will now be further described with reference to the accompanying drawings.

[0024] Figure 1 This is a flowchart of the present invention. Detailed Implementation

[0025] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0026] like Figure 1 As shown, a method for pre-lamination processing of a PCB board is characterized by the following specific steps:

[0027] Step 1: Etch the inner layer board containing PTFE material to obtain the inner layer board of the PCB board;

[0028] Step 2: Clean and dry the etched inner layer board to remove the liquid from the surface of the inner layer board and keep the surface of the inner layer board dry.

[0029] Step 3: Perform plasma treatment on the dried inner layer board. The plasma treatment includes plasma etching, plasma cleaning and plasma activation. When performing plasma treatment on the inner layer board, plasma etching, plasma cleaning and plasma activation are performed in sequence.

[0030] Step 4: Transfer the plasma-treated board to the lamination process for subsequent pressing.

[0031] The intervals between the plasma etching, plasma cleaning, and plasma activation steps shall not exceed 10 minutes. The plasma etching, plasma cleaning, and plasma activation need to be kept at a short interval in order to effectively ensure the plasma treatment effect. Plasma etching uses plasma to roughen the surface of the board, increase the microscopic surface area, and improve the bonding force.

[0032] The plasma etching process utilizes N2, CF4, and O2 at 80°C to treat the inner layer board for 20-30 minutes to achieve a plasma etching effect, thereby roughening the board surface. The flow rate ratio of N2, CF4, and O2 is 200ml / min:250ml / min:1800ml / min. The plasma cleaning process utilizes O2 and N2 at 80°C to treat the inner layer board for 10-15 minutes to achieve a plasma cleaning effect. During the plasma etching process, a large amount of residue is easily generated on the board surface after being exposed to plasma, contaminating the board surface. Therefore, plasma cleaning is required before proceeding to the next step. The flow rate ratio of O2 and N2 is 200ml / min:800ml / min. The plasma activation process utilizes N2 at 80°C to treat the inner layer board for 10 minutes. Plasma etching, plasma cleaning, and plasma activation are performed to introduce hydrophilic groups onto the PTFE surface through the action of O2 and N2, transforming the originally hydrophobic PTFE material into a hydrophilic interface and improving adhesion. The flow rate of N2 is 1000 ml / min. The functions of plasma etching, plasma cleaning, and plasma activation are as follows: Plasma etching uses plasma to roughen the surface of the board, increasing the microscopic surface area and improving adhesion; during plasma etching, a large amount of residue is easily generated on the board surface after being subjected to plasma, contaminating the board surface, so plasma cleaning is required before the next step of processing; plasma activation introduces hydrophilic groups onto the PTFE surface through the action of O2 and N2, transforming the originally hydrophobic PTFE material into a hydrophilic interface and improving adhesion.

[0033] The beneficial effect of this invention is that, for the pre-lamination treatment of inner layer plates containing PTFE material, the traditional method is to use sodium naphthalene solution for treatment. Sodium naphthalene solution is formed by dissolving or complexing metallic sodium in active ethers such as tetrahydrofuran, ethylene glycol dimethyl ether and naphthalene. The sodium in the treatment solution can break the CF bond on the PTFE surface, remove F atoms, and cause the surface to be defluorinated and form a carbonized layer. However, this treatment method has significant drawbacks: sodium metal is highly reactive, making it prone to safety accidents during storage and production; it generates large amounts of toxic and harmful waste liquid, damaging the environment; the treated board surface must be pressed within a short time, and the adhesion performance of the board surface decreases exponentially over time. By ion-treating the inner layer board containing PTFE material, sequentially completing plasma etching, plasma cleaning, and plasma activation, the surface of the board can be roughened, increasing the microscopic surface area and improving the bonding strength. This replaces the traditional sodium naphthalene solution treatment method, effectively improving its safety, reducing environmental pollution, and enhancing the pressing effect of the board. The plasma treatment method is simple, safe, and easy to operate, and does not generate a large amount of waste, which has significant benefits for safe production and environmental protection.

[0034] The plasma treatment method involves three steps: plasma etching, which roughens the surface of the board using plasma to increase the microscopic surface area and improve adhesion; plasma cleaning, which removes residue generated during plasma etching; and plasma activation, which introduces hydrophilic groups into the PTFE surface through the action of O2 and N2, transforming the originally hydrophobic PTFE material into a hydrophilic interface and further enhancing adhesion. These three steps respectively increase surface area, clean the board surface, and improve the surface energy of the board, thus improving the adhesion performance of the board from three dimensions. Compared with the traditional sodium naphthalene treatment method, this method has significant advantages in terms of technology, economy, and social benefits.

[0035] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to any specific implementation. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A method for pre-processing a PCB board before lamination, characterized in that, The specific steps of this production method are as follows: Step 1: Etch the inner layer board containing PTFE material to obtain the inner layer board of the PCB board; Step 2: Clean and dry the etched inner layer board to remove the liquid from the surface of the inner layer board and keep the surface of the inner layer board dry. Step 3: Perform plasma treatment on the dried inner layer board. The plasma treatment includes plasma etching, plasma cleaning and plasma activation operations. When performing plasma treatment on the inner layer board, plasma etching, plasma cleaning and plasma activation are performed in sequence. Step 4: Transfer the plasma-treated board to the lamination process for subsequent pressing treatment; The plasma etching process involves treating the inner layer board with N2, CF4, and O2 at 80°C for 20-30 minutes to achieve a plasma etching effect, thereby roughening the surface of the board. The flow rate ratio of N2, CF4, and O2 is 200 ml / min: 250 ml / min: 1800 ml / min; The plasma cleaning process involves treating the inner layer plate with O2 and N2 at 80°C for 10-15 minutes to achieve the plasma cleaning effect. The flow rate ratio of O2 to N2 is 200 ml / min: 800 ml / min; The plasma activation is achieved by treating the inner layer plate with N2 at 80°C for 10 minutes. The flow rate of N2 is 1000 ml / min.

2. The method for pre-lamination processing of a PCB board according to claim 1, characterized in that, The intervals between the plasma etching, plasma cleaning, and plasma activation steps shall not exceed 10 minutes.

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