Low-impedance anti-static composite circuit board and manufacturing method thereof

Abstract

The invention discloses a low-impedance anti-static composite circuit board and a manufacturing method thereof, and the method comprises the following steps: S1, selecting a substrate material which is a composite material with a low dielectric constant and a low dielectric loss factor, the composite material comprises ABS (Acrylonitrile Butadiene Styrene) resin, a styrene-butadiene copolymer, conductive particles and reinforced fibers, s2, optimizing the proportion of the ABS resin to other components in the substrate material; s3, designing a circuit layout, optimizing grounding connection in a low-impedance mode, and surrounding the electroplating through hole on a grounding plane in the circuit board; s4, attenuating ESD current by using a magnetic substance in the design of the circuit board, and improving electromagnetic field resistance caused by indirect ESD by adopting the design of a multi-layer board; and S5, strict moisture-proof and anti-static measures are taken in the processing process of the circuit board A. By adopting the method to manufacture the circuit board, the dielectric property, the mechanical property, the antistatic capability, the electromagnetic compatibility and the production quality of the circuit board are remarkably improved.

Description

Technical Field

[0001] The present invention relates to the field of circuit board manufacturing technology, and in particular to a low-impedance anti-static composite circuit board and a manufacturing method thereof. Background Art

[0002] In the rapid development of the electronics industry, printed circuit boards (PCBs) are an indispensable basic component in electronic products, and their performance directly determines the working stability and efficiency of electronic equipment. With the high performance and miniaturization of electronic equipment, the performance requirements for PCBs are getting higher and higher. Especially in high-frequency, high-speed, and high-power electronic systems, the dielectric properties, mechanical properties, antistatic ability, and electromagnetic compatibility of PCBs have become key considerations in design and manufacturing.

[0003] There are several limitations in traditional PCB materials and manufacturing methods, which restrict the further improvement of PCB performance: 1. Traditional PCB substrate materials usually have a high dielectric constant and dielectric loss factor, which limits the transmission speed of signals and increases signal loss. 2. In order to improve the antistatic and flame retardant properties of PCBs, traditional methods may sacrifice the mechanical properties of the substrate, resulting in the substrate being easily damaged during assembly and use. 3. The deficiencies of traditional PCBs in antistatic and flame retardant properties limit their application in specific environments. 4. With the increase in the operating frequency of electronic equipment, traditional PCBs perform poorly in electromagnetic compatibility, cannot effectively resist external electromagnetic interference, and are difficult to meet increasingly stringent EMC standards. 5. Traditional PCBs lack effective ESD (electrostatic discharge) protection measures, making sensitive electronic components vulnerable to damage during assembly and use. In view of the above limitations, the industry urgently needs a new PCB manufacturing method to solve the above problems. Summary of the invention

[0004] In view of this, the present invention aims to address the deficiencies in the prior art, and its main purpose is to provide a low-impedance anti-static composite circuit board and a method for manufacturing the same, which significantly improves the dielectric properties, mechanical properties, anti-static ability, electromagnetic compatibility and production quality of the circuit board through innovative measures such as precise material ratios, circuit layout optimization, magnetic material application, multi-layer board design, strict production environment control and substrate material pretreatment, overcomes the limitations of traditional circuit boards, and meets the needs of modern electronic equipment for high-performance circuit boards.

[0005] To achieve the above purpose, the present invention adopts the following technical solutions:

[0006] A method for manufacturing a low-impedance anti-static composite circuit board comprises the following steps:

[0007] S1. Selecting a substrate material, wherein the substrate material is a composite material having a low dielectric constant and a low dielectric loss factor, and the composite material comprises ABS resin, styrene-butadiene copolymer, conductive particles and reinforcing fibers;

[0008] S2. Optimizing the ratio of ABS resin to other components in the substrate material to improve antistatic properties and flame retardancy without significantly reducing mechanical properties;

[0009] S3. Design the circuit layout, optimize the ground connection in a low impedance manner, and surround the plated through-holes with the ground plane inside the circuit board;

[0010] S4. Use magnetic materials to attenuate ESD current in circuit board design, and use multi-layer board design to improve electromagnetic field resistance caused by indirect ESD;

[0011] S5. Implement strict moisture-proof and anti-static measures during the processing of circuit board A, maintain a constant temperature and humidity in the workshop, and regularly maintain equipment to prevent the accumulation of conductive particles.

[0012] As a preferred embodiment, in step S1, the ABS resin accounts for 60% to 80% of the total weight, the styrene-butadiene copolymer accounts for 10% to 20% of the total weight, the volume ratio of the conductive particles is 0.5% to 2%, and the volume ratio of the reinforcing fibers is 5% to 15%.

[0013] As a preferred solution, step S2 also includes the following steps:

[0014] S201, determining an initial ratio of ABS resin, which is a main component of the substrate material;

[0015] S202, selecting a quaternary ammonium salt compound as an antistatic agent, and selecting a halogen compound or a phosphorus compound as a flame retardant;

[0016] S203, conduct a small-scale laboratory test, mix ABS resin, antistatic agent and flame retardant in different proportions, and test the mechanical properties, antistatic properties and flame retardant properties of each mixture;

[0017] S204. According to the test results, the optimal ratio is selected to ensure that the mechanical property loss is minimized while meeting the antistatic and flame retardancy requirements;

[0018] S205. Before large-scale production, pilot scale-up is carried out to verify the repeatability and stability of small-scale test results;

[0019] S206: Determine the final formula ratio and carry out batch production.

[0020] As a preferred solution, step S3 also includes the following steps:

[0021] S301. Use EDA software to design the circuit board layout to ensure that the circuit layout is reasonable and reduce signal interference;

[0022] S302. Design the grounding network to ensure that all grounding points are connected to the main grounding plane to form a complete grounding system;

[0023] S303, optimizing the design of the ground plane to reduce the ground impedance, which can be achieved by increasing the area of ​​the ground plane or using multi-layer grounding;

[0024] S304. Design plated through holes inside the circuit board and ensure that these holes are surrounded by ground planes to provide a good ground path;

[0025] S305, performing simulation analysis on the ground connection to ensure that the ground impedance remains within an acceptable range under high frequency operation;

[0026] S306. During the circuit board production process, ensure the manufacturing accuracy and quality of the ground connection to meet the design requirements.

[0027] As a preferred solution, step S4 also includes the following steps:

[0028] S401, selecting ferrite as the magnetic material;

[0029] S402, determining the placement of magnetic materials in the circuit board design, and placing them near the ESD sensitive area;

[0030] S403. Design a multilayer board structure including at least two grounding layers to enhance the electromagnetic shielding effect;

[0031] S404. Use electromagnetic field simulation software to simulate and analyze the circuit board design, optimize the placement of magnetic materials and multilayer board structure to improve ESD protection capabilities;

[0032] S405. During the circuit board production process, ensure the correct placement of magnetic materials and the precise manufacturing of multilayer board structures.

[0033] As a preferred solution, step S5 also includes the following steps:

[0034] S501. Establish workshop environment control standards, including temperature, humidity and cleanliness;

[0035] S502, install temperature and humidity control system;

[0036] S503. Clean and maintain production equipment regularly;

[0037] S504. Use anti-static floors, anti-static workbenches and anti-static packaging materials;

[0038] S505. Workers should wear anti-static wristbands and anti-static shoes during the production process to reduce the generation of static electricity;

[0039] S506. Regularly inspect and evaluate anti-static and moisture-proof measures to ensure their effectiveness.

[0040] As a preferred solution, the conductive particles are carbon fibers or metal fillers, and the reinforcing fibers are preferably carbon fibers or glass fibers.

[0041] As a preferred solution, the magnetic substance is a ferrite material that can attenuate ESD current.

[0042] As a preferred solution, the method further includes pre-treating the substrate material to improve the bonding strength of subsequent lamination and coating by cleaning, roughening, activating and plasma treatment.

[0043] A low-impedance antistatic composite circuit board comprises a substrate manufactured by the manufacturing method, a conductive pattern formed on the substrate, at least one ESD protection element arranged on the conductive pattern, at least two grounding layers in the circuit board and a three-conformal paint layer coated on the surface of the substrate.

[0044] Compared with the prior art, the present invention has obvious advantages and beneficial effects. Specifically, it can be seen from the above technical scheme that, first, the material ratio is accurately optimized; the ABS resin, styrene-butadiene copolymer, conductive particles and reinforcing fibers are accurately matched to achieve low dielectric constant and low dielectric loss factor. This precise material ratio optimization makes the composite PCB circuit board significantly superior to traditional materials in electromagnetic performance, and improves the transmission speed and quality of signals.

[0045] Second, refinement of circuit layout and grounding design; reducing signal interference and improving grounding impedance. Through refined circuit layout and grounding design, signal interference problems in high-frequency applications are reduced and the performance and reliability of circuit boards are improved.

[0046] Third, the application of magnetic materials and multi-layer board design; use magnetic materials and multi-layer board design to improve ESD protection capabilities and electromagnetic field resistance; this design provides more effective ESD protection, reduces the damage caused by electrostatic discharge to the circuit board, and enhances electromagnetic compatibility.

[0047] Fourth: Pretreatment of substrate materials; pretreatment of substrate materials to improve the bonding strength of lamination and coating; the pretreatment step improves the bonding strength and durability of the substrate, reduces defects in the manufacturing process, and improves the overall quality of the product.

[0048] In order to more clearly illustrate the structural features and effects of the present invention, it is described in detail below in conjunction with the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 It is a schematic diagram of the process flow of the circuit board manufacturing method of the present invention;

[0050] Figure 2 It is a schematic diagram of the layered structure of the circuit board of the present invention.

[0051] Description of the accompanying drawings:

[0052] 10. Substrate; 20. Ground layer; 30. Power layer; 40. Signal layer; 50. Insulation layer; 60. Via; 70. Conformal coating layer. DETAILED DESCRIPTION

[0053] The present invention Figure 1 and Figure 2 As shown, a low-impedance anti-static composite circuit board and a manufacturing method thereof, wherein:

[0054] The preparation method comprises the following steps:

[0055] S1. Select a substrate material, the substrate material is a composite material with low dielectric constant and low dielectric loss factor, the composite material includes ABS resin, styrene-butadiene copolymer, conductive particles and reinforcing fibers; in step S1, the ABS resin accounts for 60% to 80% of the total weight, the styrene-butadiene copolymer accounts for 10% to 20% of the total weight, the volume ratio of the conductive particles is 0.5% to 2%, and the volume ratio of the reinforcing fibers is 5% to 15%; the conductive particles are carbon fibers or metal fillers, and the reinforcing fibers are preferably carbon fibers or glass fibers. The addition of these high-performance materials can significantly improve the conductivity and mechanical strength of the PCB. The substrate material combines ABS resin, styrene-butadiene copolymer, conductive particles and reinforcing fibers to achieve low dielectric constant and low dielectric loss factor, which helps to increase signal transmission speed and reduce signal attenuation; compared with traditional materials, this composite material provides better electromagnetic properties, mechanical properties and heat resistance.

[0056] In addition, the volume ratio of conductive particles and reinforcing fibers is precisely controlled to achieve specific electrical and mechanical properties. This precise control provides more consistent product performance and can be adjusted as needed to meet specific application requirements.

[0057] S2, optimize the ratio of ABS resin to other ingredients in the substrate material to improve antistatic and flame retardancy without significantly reducing mechanical properties; step S2, also includes the following operating steps: S201, determine the initial ratio of ABS resin, which is the main component of the substrate material; S202, select suitable antistatic agents and flame retardants, such as quaternary ammonium salt compounds for antistatic agents, and halogen compounds or phosphorus compounds for flame retardants; S203, conduct laboratory small-scale tests, mix ABS resin, antistatic agent and flame retardant in different proportions, and test the mechanical properties, antistatic properties and flame retardancy of each mixture; S204, select the optimal ratio according to the test results to ensure that the mechanical properties are minimized while meeting the antistatic and flame retardancy requirements; S205, before large-scale production, conduct pilot scale-up to verify the repeatability and stability of small-scale test results; S206, determine the final formula ratio and carry out mass production. Through detailed steps to optimize the ratio of ABS resin to other ingredients to achieve the best balance of antistatic and flame retardancy, this method can ensure better antistatic and flame retardancy without sacrificing mechanical properties.

[0058] S3, design the circuit layout, optimize the ground connection in a low impedance manner, and surround the plated through hole in the ground plane inside the circuit board; Step S3 also includes the following operation steps: S301, use EDA software to design the circuit board layout, ensure that the circuit layout is reasonable and reduce signal interference; S302, design the grounding network, ensure that all grounding points are connected to the main ground plane to form a complete grounding system; S303, optimize the design of the ground plane to reduce the ground impedance, which can be achieved by increasing the area of ​​the ground plane or using multi-faceted grounding; S304, design the plated through hole (PTH) inside the circuit board, and ensure that these holes are surrounded by the ground plane to provide a good grounding path; S305, simulate and analyze the ground connection to ensure that the ground impedance remains within an acceptable range under high-frequency operation; S306, in the production process of the circuit board, ensure the manufacturing accuracy and quality of the ground connection to meet the design requirements. The optimization of the ground connection is particularly emphasized in the circuit layout design to achieve low impedance; the optimized grounding design can reduce signal interference and improve the performance of the circuit, especially in high-frequency applications, it can reduce the reflection and attenuation of high-frequency signals. The ground connection is designed to minimize the impedance of the working ground plane and the gap caused by the via to optimize the ground connection and surround the plated through hole.

[0059] S4. Use magnetic materials to attenuate ESD current in circuit board design, and adopt multi-layer board design to improve electromagnetic field resistance caused by indirect ESD; step S4 also includes the following operation steps: S401. Select suitable magnetic materials, such as ferrite, to attenuate ESD current; S402. Determine the placement of magnetic materials in circuit board design and place them near ESD sensitive areas; S403. Design a multi-layer board structure, including at least two grounding layers, to enhance the electromagnetic shielding effect; S404. Use electromagnetic field simulation software to simulate and analyze the circuit board design, optimize the placement of magnetic materials and the multi-layer board structure, so as to improve the ESD protection capability; S405. Ensure the correct placement of magnetic materials and the precise manufacture of multi-layer board structures during the production process of circuit boards; the magnetic material is a ferrite material that can attenuate ESD current, and the ferrite material can ensure the ESD protection effect of the circuit board. Moreover, the ferrite material is relatively low in cost, which helps to control the production cost of the circuit board.

[0060] Magnetic materials are used in circuit board design to attenuate ESD current, and multi-layer board design is used to improve electromagnetic field resistance; magnetic materials can effectively absorb and attenuate ESD current and protect sensitive circuits; multi-layer board design improves the electromagnetic compatibility of circuit boards and reduces the impact of external electromagnetic interference.

[0061] S5. Implement strict moisture-proof and anti-static measures during the processing of circuit board A, such as maintaining a constant temperature and humidity in the workshop, and regularly maintaining equipment to prevent the accumulation of conductive particles. Step S5 also includes the following operating steps: S501. Formulate workshop environmental control standards, including temperature, humidity and cleanliness; S502. Install temperature and humidity control systems, such as air conditioners and dehumidifiers, to maintain constant environmental conditions; S503. Regularly clean and maintain production equipment, especially those that are prone to static electricity, such as drilling machines, laminators, etc.; S504. Use anti-static materials, such as anti-static floors, anti-static workbenches and anti-static packaging materials; S505. Workers wear anti-static wristbands and anti-static shoes during the production process to reduce the generation of static electricity; S506. Regularly inspect and evaluate anti-static and moisture-proof measures to ensure the effectiveness of the measures. This step implements comprehensive moisture-proof and anti-static measures, including environmental control and equipment maintenance; by controlling the production environment, the reliability of circuit boards in different environments is improved, production accidents caused by moisture and static electricity are reduced, and production efficiency is improved.

[0062] In addition, the manufacturing method also includes pre-treating the substrate material to improve the bonding strength of subsequent lamination and plating by cleaning, roughening, activation and plasma treatment; the pre-treatment can ensure good bonding between the substrate material and the lamination and plating, improve the overall strength of the PCB, reduce defects such as delamination and bubbles caused by poor bonding, and improve product quality.

[0063] It also includes the use of anti-static workbenches during the production process, and impedance simulation and electrostatic discharge analysis during the circuit board design phase to ensure that the design meets low impedance and anti-static requirements. It also includes the three-conformal coating treatment after the manufacturing is completed to increase the corrosion resistance and moisture resistance of the circuit board and extend its service life. The humidity, temperature and cleanliness of the clean room are controlled during the manufacturing process, and the circuit board is pre-baked before welding to remove moisture and prevent welding defects.

[0064] Specifically, during the production of circuit boards, the environmental conditions of the clean room are strictly controlled to ensure product quality and reliability. A precise temperature and humidity control system, including air conditioners and dehumidifiers, is installed to maintain constant temperature and humidity, thereby preventing the generation of static electricity and reducing the impact of moisture on the circuit boards. In addition, an anti-static workbench is used to ensure that static electricity generated during assembly and testing is effectively controlled. Operators must wear anti-static clothing, including anti-static wristbands and shoes, to further reduce electrostatic discharge incidents.

[0065] After the circuit board is manufactured, it is coated with three anti-corrosion paint (moisture-proof, salt spray-proof, and dust-proof). This step increases the corrosion resistance and moisture resistance of the circuit board by forming a protective film, effectively extending the service life of the product. Before soldering components, the circuit board is pre-baked. This key step helps remove moisture from the board and the hole wall, thereby preventing bubbles and other defects during soldering. These meticulous post-manufacturing treatments ensure the long-term stability of the PCB and its durability in harsh environments.

[0066] A low-impedance anti-static composite circuit board manufactured by the above manufacturing method comprises: a substrate, a conductive pattern formed on the substrate, at least one ESD protection element arranged on the conductive pattern, at least two grounding layers in the circuit board, and a conformal coating layer coated on the surface of the substrate. The specific structure comprises a substrate 10, a grounding layer 20, a power layer 30, a signal layer 40, an insulating layer 50, a conformal coating layer 70, and vias 60, and the distribution method is as shown in the attached figure. Figure 2 This circuit board structure is not only optimized in electrical performance, but also enhanced in physical protection, providing comprehensive protection; the three-conformal coating layer can protect the PCB from moisture, dust and chemical corrosion, extending the service life of the PCB.

[0067] The design focus of the present invention is that

[0068] First, precise optimization of material ratio; precise ratio of ABS resin, styrene-butadiene copolymer, conductive particles and reinforcing fibers to achieve low dielectric constant and low dielectric loss factor. This precise optimization of material ratio makes the composite PCB circuit board significantly better than traditional materials in electromagnetic performance, and improves the transmission speed and quality of signals.

[0069] Second, refinement of circuit layout and grounding design; reducing signal interference and improving grounding impedance. Through refined circuit layout and grounding design, signal interference problems in high-frequency applications are reduced and the performance and reliability of circuit boards are improved.

[0070] Third, the application of magnetic materials and multi-layer board design; use magnetic materials and multi-layer board design to improve ESD protection capabilities and electromagnetic field resistance; this design provides more effective ESD protection, reduces the damage caused by electrostatic discharge to the circuit board, and enhances electromagnetic compatibility.

[0071] Fourth: Pretreatment of substrate materials; pretreatment of substrate materials to improve the bonding strength of lamination and coating; the pretreatment step improves the bonding strength and durability of the substrate, reduces defects in the manufacturing process, and improves the overall quality of the product.

[0072] The above description is only a preferred embodiment of the present invention and does not limit the technical scope of the present invention. Therefore, any slight modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A method for manufacturing a low-impedance anti-static composite circuit board, characterized in that: The following steps are involved: S1. Selecting a substrate material, wherein the substrate material is a composite material having a low dielectric constant and a low dielectric loss factor, and the composite material comprises ABS resin, styrene-butadiene copolymer, conductive particles and reinforcing fibers; S2. Optimizing the ratio of ABS resin to other components in the substrate material to improve antistatic properties and flame retardancy without significantly reducing mechanical properties; S3. Design the circuit layout, optimize the ground connection in a low impedance manner, and surround the plated through-holes with the ground plane inside the circuit board; S4. Use magnetic materials to attenuate ESD current in circuit board design, and use multi-layer board design to improve electromagnetic field resistance caused by indirect ESD; S5. Implement strict moisture-proof and anti-static measures during the processing of circuit board A, maintain a constant temperature and humidity in the workshop, and regularly maintain equipment to prevent the accumulation of conductive particles.

2. The method for manufacturing a low-impedance antistatic composite circuit board according to claim 1, characterized in that: In step S1, the ABS resin accounts for 60% to 80% of the total weight, the styrene-butadiene copolymer accounts for 10% to 20% of the total weight, the volume ratio of the conductive particles is 0.5% to 2%, and the volume ratio of the reinforcing fibers is 5% to 15%.

3. The method for manufacturing a low-impedance anti-static composite circuit board according to claim 1, characterized in that: Step S2 also includes the following steps: S201, determining an initial ratio of ABS resin, which is a main component of the substrate material; S202, selecting a quaternary ammonium salt compound as an antistatic agent, and selecting a halogen compound or a phosphorus compound as a flame retardant; S203, conduct a small-scale laboratory test, mix ABS resin, antistatic agent and flame retardant in different proportions, and test the mechanical properties, antistatic properties and flame retardant properties of each mixture; S204. According to the test results, the optimal ratio is selected to ensure that the loss of mechanical properties is minimal while meeting the antistatic and flame retardant requirements; S205. Before large-scale production, pilot scale-up is carried out to verify the repeatability and stability of small-scale test results; S206: Determine the final formula ratio and carry out batch production.

4. The method for manufacturing a low-impedance antistatic composite circuit board according to claim 1, characterized in that: Step S3 also includes the following steps: S301. Use EDA software to design the circuit board layout to ensure that the circuit layout is reasonable and reduce signal interference; S302. Design the grounding network to ensure that all grounding points are connected to the main grounding plane to form a complete grounding system; S303, optimizing the design of the ground plane to reduce the ground impedance, which can be achieved by increasing the area of ​​the ground plane or using multi-layer grounding; S304. Design plated through holes inside the circuit board and ensure that these holes are surrounded by ground planes to provide a good ground path; S305, performing simulation analysis on the ground connection to ensure that the ground impedance remains within an acceptable range under high frequency operation; S306. During the circuit board production process, ensure the manufacturing accuracy and quality of the ground connection to meet the design requirements.

5. The method for manufacturing a low-impedance anti-static composite circuit board according to claim 1, characterized in that: Step S4 also includes the following steps: S401, selecting ferrite as the magnetic material; S402, determining the placement of magnetic materials in the circuit board design, and placing them near the ESD sensitive area; S403. Design a multilayer board structure including at least two grounding layers to enhance the electromagnetic shielding effect; S404. Use electromagnetic field simulation software to simulate and analyze the circuit board design, optimize the placement of magnetic materials and multilayer board structure to improve ESD protection capabilities; S405. During the circuit board production process, ensure the correct placement of magnetic materials and the precise manufacturing of multilayer board structures.

6. The method for manufacturing a low-impedance anti-static composite circuit board according to claim 1, characterized in that: Step S5 also includes the following steps: S501. Establish workshop environment control standards, including temperature, humidity and cleanliness; S502, install temperature and humidity control system; S503. Clean and maintain production equipment regularly; S504. Use anti-static floors, anti-static workbenches and anti-static packaging materials; S505. Workers should wear anti-static wristbands and anti-static shoes during the production process to reduce the generation of static electricity; S506. Regularly inspect and evaluate anti-static and moisture-proof measures to ensure their effectiveness.

7. The method for manufacturing a low-impedance antistatic composite circuit board according to claim 1, characterized in that: The conductive particles are carbon fibers or metal fillers, and the reinforcing fibers are preferably carbon fibers or glass fibers.

8. The method for manufacturing a low-impedance antistatic composite circuit board according to claim 1, characterized in that: The magnetic material is a ferrite material capable of attenuating ESD current.

9. The method for manufacturing a low-impedance antistatic composite circuit board according to claim 1, characterized in that: It also includes pre-treatment of substrate materials to improve the bonding strength of subsequent lamination and plating through cleaning, roughening, activation and plasma treatment.

10. A low impedance antistatic composite circuit board, characterized in that include: A substrate manufactured by the manufacturing method according to any one of claims 1 to 9, a conductive pattern formed on the substrate, at least one ESD protection element arranged on the conductive pattern, at least two grounding layers in the circuit board, and a conformal coating layer coated on the surface of the substrate.

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