Circuit board and press-fit manufacturing method thereof

Abstract

The invention provides a circuit board and a lamination manufacturing method thereof, and the method comprises the steps: carrying out the depth-controlled etching of a copper plate, so as to enable the top surface of the copper plate to be provided with a boss; performing dry film pasting operation on the top surface of the double-sided board, and forming a circuit on the bottom surface of the double-sided board; performing hole milling operation on the double-sided board so that the double-sided board is provided with a first milling groove; hole milling operation is carried out on the prepreg, so that the prepreg is provided with a second milling groove, and the first milling groove is communicated with the second milling groove; the double-sided board, the semi-cured board and the copper board are laminated to form a board to be laminated, and the boss extends out of the top surface of the double-sided board; laminating films on the upper surface and the lower surface of the to-be-laminated plate; and pressing the to-be-pressed plate on which the covering film is attached, so as to form a pressed plate. The top surface of the boss is covered by the covering film, so that the colloid formed by melting the semi-solidified plate does not overflow to the top surface of the boss, the electrical performance and long-term reliability of the circuit board in subsequent use are ensured, and the production efficiency of the circuit board is ensured.

Description

Technical Field

[0001] This disclosure relates to the technical field of circuit boards, and in particular to a circuit board and a method for laminating and manufacturing the same. Background Technology

[0002] PCBs are important electronic components, serving as the support for electronic components and the carrier for electrical connections between them. Copper-embedded aluminum bosses are a type of metal PCB board, used in areas where switching elements, power supplies, and power amplifiers are assembled. They can be applied in high-power industrial, lighting, and automotive circuit board processing technologies.

[0003] Existing circuit board manufacturing methods, such as the copper-based printed circuit board with bosses and its processing method disclosed in Chinese patent CN113260139A, involve placing a prepreg board and a laminate in sequence and then laminating them together. However, during the lamination process, the PP board forms PP glue due to the high temperature, and some of the PP glue overflows onto the surface of the bosses. This causes damage to the electrical performance of the circuit board during subsequent use and a decrease in long-term reliability. The presence of these problems requires rework, which affects the production efficiency of the circuit board. Summary of the Invention

[0004] The purpose of this disclosure is to overcome the shortcomings of the prior art and provide a circuit board and its lamination manufacturing method that effectively prevents glue overflow and ensures the production quality of the circuit board.

[0005] The purpose of this disclosure is achieved through the following technical solution: A method for laminating and manufacturing a circuit board includes the following steps: S101. Perform a controlled-depth etching step on the copper plate to create a boss on the top surface of the copper plate. S102. Apply dry film to the top surface of the double-sided board and form the circuit on the bottom surface of the double-sided board. S103. Perform a milling operation on the double-sided panel to give the double-sided panel a first milling groove; S104. Perform a milling operation on the prepreg to give the prepreg a second milling groove, wherein the first milling groove is connected to the second milling groove. S105. The double-sided panel, the semi-cured board and the copper plate are stacked to form a board to be pressed together, wherein the boss is sequentially inserted into the second groove and the first groove, and the boss protrudes from the top surface of the double-sided panel, and the width of the first groove is smaller than the width of the second groove. S106. Apply a molding film to the upper and lower surfaces of the plate to be pressed. S107. The plate to be pressed after the cover film is applied is pressed to form a pressed plate.

[0006] In one embodiment, after S101 and before S102, the following steps are included: drilling a hole in the copper plate to give the copper plate a first rivet hole.

[0007] In one embodiment, after S103 and before S104, the following steps are included: drilling a hole in the prepreg to give the prepreg a second rivet hole, wherein the first rivet hole is connected to the second rivet hole.

[0008] In one embodiment, after S102 and before S103, the following steps are included: drilling a hole in the double-sided panel to give the double-sided panel a third rivet hole, wherein the third rivet hole, the second rivet hole and the first rivet hole are sequentially connected.

[0009] In one embodiment, executing S105 specifically includes the following steps: The double-sided panel, the semi-cured board, and the copper plate are stacked using rivets to form a board to be pressed together. The boss is sequentially inserted into the second groove and the first groove, and the boss extends from the top surface of the double-sided panel. The rivets are sequentially inserted into the third rivet hole, the second rivet hole, and the first rivet hole.

[0010] In one embodiment, the length of the rivet is equal to the sum of the depths of the first rivet hole, the second rivet hole, and the third rivet hole.

[0011] In one embodiment, the width of the first groove is 2-3 mil larger than the width of the boss.

[0012] In one embodiment, the width of the second groove is 6-8 mil larger than the width of the boss.

[0013] In one embodiment, the height of the boss is greater than the total thickness of the double-sided panel and the prepreg, and the height of the boss is 10-15 μm.

[0014] A circuit board is manufactured using any of the circuit board lamination methods described in the above embodiments.

[0015] Compared with the prior art, this disclosure has at least the following advantages: During circuit board production, double-sided boards and prepregs are drilled with holes, followed by the assembly of copper plates, prepregs, and double-sided boards. A boss on the top surface of the copper plate passes through the second and first drilling grooves, and extends from the top surface of the double-sided board, forming a board to be pressed. A molding film is then applied to both sides of the board to cover the top surface of the boss, the double-sided board, and the copper plate. Before pressing, the width of the first drilling groove is smaller than the width of the second drilling groove. During the pressing process, the prepreg melts to form a colloid. Because the top surface of the boss is covered by the molding film, the stress on the double-sided board from the downward pressure of the steel plate decreases. This allows the colloid formed by the melting prepreg to flow into the corner between the boss and the copper plate, filling the gap between them. Furthermore, the colloid is less likely to overflow onto the top surface of the boss, ensuring the electrical performance and long-term reliability of the circuit board during subsequent use, as well as maintaining production efficiency. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of this disclosure, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of this disclosure and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a flowchart of a circuit board lamination manufacturing method in one embodiment; Figure 2 This is a cross-sectional view of the circuit board before assembly in one embodiment; Figure 3 for Figure 2 The diagram shown is a cross-sectional view of the assembled circuit board. Figure 4 for Figure 2 The diagram shows a cross-sectional view of the circuit board shown. Figure 5 This is a cross-sectional view of the copper plate of the circuit board in another embodiment; Figure 6 This is a cross-sectional view of the copper plate of the circuit board in another embodiment.

[0018] Reference numerals: 100, copper plate; 101, first rivet hole; 102, anti-overflow groove; 103, anti-overflow flow channel; 110, boss; 111, tiered flow channel; 200, double-sided panel; 201, first groove; 202, third rivet hole; 300, prepreg; 301, second groove; 302, second rivet hole; 400, molding film; 500, rivet. Detailed Implementation

[0019] To facilitate understanding of this disclosure, a more complete description will be given below with reference to the accompanying drawings, which illustrate preferred embodiments of the present disclosure. However, this disclosure can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure.

[0020] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly attached to the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of this disclosure. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0022] To better understand the technical solutions and beneficial effects of this disclosure, the following detailed description is provided in conjunction with specific embodiments: Please see Figure 1 The present invention provides a method for fabricating a circuit board by lamination, comprising the following steps: S101. A depth-controlled etching step is performed on the copper plate 100 to form a boss 110 on the top surface of the copper plate 100. In this embodiment, a copper plate 100 is first obtained, and the copper plate 100 is etched. Specifically, a depth-controlled etching step is performed to control the etching depth of the copper plate 100 so that the boss 110 can be formed on the top surface of the copper plate 100. The effect is shown in the figure below. Figure 2 As shown.

[0023] S102. Apply a dry film to the top surface of the double-sided panel 200 and form circuits on the bottom surface of the double-sided panel 200 to prevent the double-sided panel 200 from being etched and causing structural changes during the micro-etching steps involved in subsequent steps.

[0024] S103. Perform a milling operation on the double-sided panel 200 so that the double-sided panel 200 has a first milling groove 201, which is to prepare in advance for the boss 110 on the copper plate 100 to pass through the first milling groove 201 during subsequent assembly.

[0025] S104. Perform a milling operation on the prepreg 300 to give the prepreg 300 a second milling groove 301, wherein the first milling groove 201 is connected to the second milling groove 301. This prepares the copper plate 100 for the boss 110 to pass through the second milling groove 301 and the first milling groove 201 sequentially during subsequent assembly. The specific structure is as follows: Figure 2 As shown.

[0026] S105. The double-sided panel 200, the semi-cured board 300 and the copper plate 100 are stacked to form a board to be pressed together, wherein the boss 110 is sequentially inserted through the second groove 301 and the first groove 201, and the boss 110 protrudes from the top surface of the double-sided panel 200, and the width of the first groove 201 is smaller than the width of the second groove 301.

[0027] S106. Apply a molding film 400 to both the upper and lower surfaces of the plate to be pressed, so that the molding film 400 covers the top surface of the boss 110, as shown in the structural diagram. Figure 3 As shown.

[0028] S107. The plate to be pressed after the cover film 400 is applied is pressed to form a pressed plate, wherein the double-sided panel 200 and the copper plate 100 are bonded together by the adhesive formed by melting the semi-cured plate 300.

[0029] In this embodiment, as Figure 2 As shown, the width of the first groove 201 is smaller than the width of the second groove 301. It can be understood that the second groove 301 is formed on the prepreg 300, while the first groove 201 is formed on the double-sided panel 200. The prepreg 300 melts during the pressing process, forming a fluid colloid that bonds the double-sided panel 200 to the copper plate 100. Because the width of the first groove 201 is smaller than the width of the second groove 301, the amount of colloid formed by the melting of the prepreg 300 is controlled. The colloid formed by the melting of the prepreg 300 has sufficient space to flow towards the corner between the boss 110 and the top surface of the copper plate 100, thus preventing excessive overflow of colloid onto the surface of the double-sided panel 200 and reducing the amount of colloid overflowing from the sidewall of the boss 110.

[0030] After the lamination process is completed, the corresponding result is shown in the image below. Figure 4 As shown.

[0031] In the above embodiments, during the production of the circuit board, the double-sided board 200 and the prepreg board 300 are drilled with holes, and then the copper plate 100, the prepreg board 300, and the double-sided board 200 are assembled. The boss 110 on the top surface of the copper plate 100 passes through the second routing groove 301 and the first routing groove 201, and the boss 110 extends from the top surface of the double-sided board 200, thus forming a board to be pressed. Then, a molding film 400 is applied to both sides of the board to be pressed to cover the top surface of the boss 110, the double-sided board 200, and the copper plate 100. Before pressing, the width of the first routing groove 201 is smaller than that of the second routing groove 301. The width of the groove 301 is such that, during the pressing step, the semi-cured board 300 melts to form an adhesive. Since the top surface of the boss 110 is covered by the coating film 400, the stress on the double-sided board 200 under the pressure of the steel plate decreases. As a result, the adhesive formed by the melting of the semi-cured board 300 has a certain space to flow to the corner between the boss 110 and the copper plate 100, filling the gap between the double-sided board 200 and the copper plate 100. Moreover, the adhesive is less likely to overflow to the top surface of the boss 110, ensuring the electrical performance and long-term reliability of the circuit board during subsequent use, as well as ensuring the production efficiency of the circuit board.

[0032] In one embodiment, after S101 and before S102, the following steps are included: drilling holes in the copper plate 100 to give the copper plate 100 first rivet holes 101, which prepares the copper plate 100 for subsequent stacking operations, where rivets 500 pass through the rivet holes to form a pre-pressed laminate. The specific structure is as follows: Figure 2 As shown.

[0033] Further, after executing S103 and before executing S104, the following steps are included: drilling a hole in the prepreg board 300 to give the prepreg board 300 a second rivet hole 302, wherein the first rivet hole 101 communicates with the second rivet hole 302 so that the rivet 500 passes through the first rivet hole 101 and the second rivet hole 302 during subsequent stacking operations. This prepares the board for subsequent stacking operations by having the rivet 500 pass through the rivet holes to assemble a pre-pressed board. The specific structure is as follows: Figure 2 As shown.

[0034] Further, after executing S102 and before executing S103, the following steps are included: drilling holes in the double-sided panel 200 to give the double-sided panel 200 a third rivet hole 202, wherein the third rivet hole 202, the second rivet hole 302, and the first rivet hole 101 are sequentially connected so that in subsequent stacking operations, rivets 500 pass through the third rivet hole 202, the second rivet hole 302, and the first rivet hole 101 to assemble a pre-pressed board. That is, by drilling holes in the copper plate 100, the prepreg board 300, and the double-sided panel 200, assembly can be completed in subsequent steps by rivets 500 passing through the corresponding rivet holes. The specific structure is as follows: Figure 2 and Figure 3 As shown.

[0035] Furthermore, executing S105 specifically includes the following steps: The double-sided panel 200, the prepreg board 300, and the copper plate 100 are stacked using rivets 500 to form a board to be pressed together. The boss 110 is sequentially inserted into the second groove 301 and the first groove 201, and extends from the top surface of the double-sided panel 200. The rivets 500 are sequentially inserted into the third rivet hole 202, the second rivet hole 302, and the first rivet hole 101. In this embodiment, before fixing the double-sided panel 200, the prepreg board 300, and the copper plate 100 with the rivets 500, holes need to be drilled in these components to facilitate the rivets 500 passing through the corresponding rivet holes to fix them. Specifically, in the assembly process, the double-sided panel 200, the prepreg board 300, and the copper plate 100 are stacked in sequence, and then rivets 500 are used to pass through the third rivet hole 202, the second rivet hole 302, and the first rivet hole 101 in sequence to fix the double-sided panel 200, the prepreg board 300, and the copper plate 100, preventing one or two of them from shifting, thereby forming a plate to be pressed. The boss 110 on the copper plate 100 passes through the second groove 301 and the first groove 201 and extends out on the top surface of the double-sided panel 200 so that the top of the boss 110 can be covered by the cover film 400 when it is used later. That is to say, the cover film 400 contacts the top of the boss 110. In addition, after executing S106, a cover film 400 is applied to both sides of the plate to be pressed. On the one hand, during the pressing step, the semi-cured plate 300 melts to form a colloid, and the cover film 400 can prevent the colloid from overflowing too much on the top of the boss 110. On the other hand, during the pressing step, the pressing step is carried out by a steel plate, and the cover film 400 covers the bottom surface of the plate to be pressed, that is, one side of the copper plate 100, and also covers the rivets 500 to prevent the rivets 500 from damaging the steel plate on the pressing machine.

[0036] Furthermore, after executing S107, the following steps are included: Perform a film removal operation on the laminated plate to remove the coating film 400; The laminated board is sanded so that the height of the boss 110 is equal to the sum of the heights of the double-sided panel 200 and the semi-cured board 300.

[0037] In this embodiment, after the molding film 400 is applied to both sides of the board to be pressed, a pressing step is performed. During this process, the molding film 400 remains in contact with the top surface of the boss 110 to prevent the melted PP adhesive from overflowing onto the top surface of the boss 110. After pressing, a pressed board is formed. Then, a film removal operation is performed to remove the molding film 400, thereby facilitating subsequent steps. Next, a sanding operation is performed so that the height of the boss 110 is equal to the sum of the heights of the double-sided panel 200 and the prepreg board 300, that is, the top surface of the boss 110 is flush with the top surface of the double-sided panel 200, thereby ensuring... This ensures the flatness of the laminated board surface. Furthermore, during the lamination process, the adhesive formed by the melting of the semi-cured board 300 overflows from the gap between the sidewall of the boss 110 and the double-sided board 200. Some of the adhesive is located on the sidewall of the boss 110. Therefore, through the polishing operation, not only is the top surface of the boss 110 flush with the top surface of the double-sided board 200, but the overflowing adhesive is also effectively removed, ensuring the cleanliness of the boss 110. This allows the top surface of the boss 110 to be fully exposed, facilitating subsequent electrical connections to the circuit board and ensuring the electrical performance of the circuit board during subsequent use.

[0038] It should be noted that when performing S105, it is essential to ensure that the boss 110 extends from the top surface of the double-sided panel 200. In other words, the height of the boss 110 must be greater than the sum of the heights of the double-sided panel 200 and the prepreg 300, so that the overlay film 400 can contact the top surface of the boss 110 when it is applied to the copper plate 100. Thus, during the lamination operation, due to the temperature rise, the prepreg 300 melts, forming a fluid colloid. This colloid may overflow from the gap between the double-sided panel 200 and the sidewall of the boss 110. Since the top surface of the boss 110 contacts the overlay film 400, the overlay film 400 covers the top surface of the boss 110, preventing the colloid from overflowing onto the top surface of the boss 110. After assembling the double-sided panel 200, the prepreg board 300, and the copper plate 100, if the height of the boss 110 is less than the sum of the heights of the double-sided panel 200 and the prepreg board 300, a groove will be formed between the top surface of the boss 110 and the first groove 201 of the double-sided panel 200. During the lamination process, the prepreg board 300 melts, forming a colloid. This colloid inevitably overflows, even filling the groove on the top surface of the boss 110, preventing the top surface of the boss 110 from being exposed. This makes subsequent film removal difficult. During the lamination and polishing process, if the height of the boss 110 is equal to the sum of the heights of the double-sided board 200, the prepreg board 300, and the copper plate 100, then the top surface of the boss 110 will be flush with the top surface of the double-sided board 200. Similarly, during the lamination process, adhesive will inevitably overflow onto the top surface of the boss 110, thus compromising its cleanliness. Even if the adhesive can be removed during subsequent polishing, the flatness of the laminated board will be compromised. Both of these situations are detrimental to the circuit board production process and make it difficult to guarantee the electrical performance and long-term reliability of the circuit board. Therefore, after assembling the double-sided board 200, the prepreg board 300, and the copper plate 100, it is necessary to ensure that the boss 110 extends beyond the top surface of the double-sided board 200.

[0039] It should also be noted that the pressing step is carried out through the steel plate of the pressing device. If S107 is executed first and then S106, the semi-cured board 300 melts to form a colloid during the pressing process. This causes the thickness of the semi-cured board 300 to change, and some of the colloid will overflow along the side wall and top surface of the boss 110. If there is too much colloid, it will also submerge the top surface of the boss 110. At the same time, without the cover film 400, the change in the thickness of the semi-cured board 300 causes the overall thickness of the board to be pressed to change. At this time, the two ends of the rivet 500 are exposed outside the board to be pressed, which may also cause the rivet 500 to damage the steel plate. In order to ensure the production quality of the circuit board, the cover film 400 is first attached to both sides of the board to be pressed before the pressing step, and then the pressing operation is performed to reduce the probability of the colloid formed by the melting of the semi-cured board 300 overflowing to the top surface of the boss 110 during the pressing process, and also to reduce the probability of the rivet 500 damaging the steel plate during the pressing process.

[0040] Furthermore, the laminated board is polished, specifically by polishing with ceramic, so that the height of the boss 110 is equal to the sum of the heights of the double-sided panel 200 and the semi-cured board 300.

[0041] Furthermore, the width of the first groove 201 is 2-3 mil (50.8-76.2 μm) larger than the width of the boss 110.

[0042] Furthermore, the width of the second groove 301 is 6-8 mil (152.4-203.2 μm) larger than the width of the boss 110. Thus, during the assembly of the double-sided panel 200, the prepreg board 300, and the copper plate 100, since there is a certain distance (denoted as the first distance) between the first groove 201 and the sidewall of the boss 110, and a certain distance (denoted as the second distance) between the second groove 301 and the sidewall of the boss 110, and the first distance is greater than the second distance, the amount of adhesive formed by the melting of the prepreg board 300 overflowing from between the first groove 201 and the sidewall of the boss 110 is controlled. Simultaneously, the width of the second groove 301 is 6-8 mil larger than the width of the boss 110, ensuring sufficient space between the copper plate 100 and the double-sided panel 200 for the adhesive to fill, thus fully filling the copper electrode adhesive between the copper plate 100 and the double-sided panel 200 and reducing the probability of adhesive overflowing onto the top surface of the double-sided panel 200.

[0043] In one embodiment, the protrusion 110 extends from the top surface of the double-sided panel 200 by a height of 10-15 μm. It can be understood that the protrusion 110 extending from the top surface of the double-sided panel 200 at the micrometer level prevents the surface of the board to be laminated from appearing too abrupt. Furthermore, after the overlay film 400 is applied, it contacts the top surface of the protrusion 110. During the lamination process, the adhesive will not overflow onto the top surface of the protrusion 110, ensuring the cleanliness of the top surface. In subsequent polishing steps, the top surface of the protrusion 110 can be polished to make it flush with the top surface of the double-sided panel 200, effectively removing any overflowing adhesive and ensuring that the top surface of the protrusion 110 is fully exposed on the surface of the double-sided panel 200, facilitating subsequent processes.

[0044] In one embodiment, the length of the rivet 500 is equal to the sum of the depths of the first rivet hole 101, the second rivet hole 302, and the third rivet hole 202. It can be understood that when the length of the rivet 500 is equal to the sum of the depths of the first rivet hole 101, the second rivet hole 302, and the third rivet hole 202, the double-sided panel 200, the prepreg board 300, and the copper plate 100 can be effectively assembled and fixed to form a plate to be pressed. Subsequently, a molding film 400 is applied to both sides of the plate to be pressed to cover the rivet 500. Therefore, even if the thickness of the prepreg board 300 changes during the pressing process, the molding film 400 has a buffering function, reducing the probability of the rivet 500 damaging the steel plate.

[0045] Furthermore, the cover film 400 is a three-in-one film, which has a "PET release film + PE buffer layer + PET release film" structure. The PET release film is used to bond the surface of the double-sided panel 200 and the top of the boss 110. The PE buffer layer is used to reduce the force of the rivet 500 on the steel plate and to reduce the stress when the double-sided panel 200 and the copper plate 100 are pressed together during the pressing process.

[0046] In one embodiment, after executing S101, the following steps are included: An ablation operation is performed on the copper plate 100 to machine an anti-overflow groove 102 on the top surface of the copper plate 100. The anti-overflow groove 102 is located at the corner between the top surface of the copper plate 100 and the side wall of the boss 110. The specific structure is as follows: Figure 5 As shown.

[0047] Understandably, during the lamination process, the prepreg 300 melts to form a colloid. Some of this colloid flows along the corner between the top surface of the copper plate 100 and the side wall of the boss 110, and then overflows onto the surface of the double-sided panel 200 along the side wall of the boss 110. If the prepreg 300 is too thick, too much colloid will be generated during melting. Some of this excess colloid will overflow along the edges of the double-sided panel 200 and the copper plate 100, while another portion will overflow onto the surface of the double-sided panel 200 along the side wall of the boss 110. Since the amount of overflow is relatively large, there is a risk that some colloid will overflow onto the top surface of the boss 110, which will increase the difficulty of removing the colloid. To prevent excessive adhesive from overflowing onto the surface of the double-sided board 200, after executing S101, the copper plate 100 is ablated to form an anti-overflow groove 102. The anti-overflow groove 102 is located at the corner between the top surface of the copper plate 100 and the side wall of the boss 110. In the subsequent lamination step, when the semi-cured board 300 melts to form adhesive, some of the adhesive will first fill the anti-overflow groove 102. This makes it less likely for the adhesive to overflow onto the surface of the double-sided board 200, thus reducing the probability that the top surface of the boss 110 will be covered by adhesive. This ensures the electrical performance and long-term reliability of the circuit board during subsequent use and reduces the defect rate of circuit board production.

[0048] Furthermore, such as Figure 6 As shown, the copper plate 100 is subjected to an ablation operation, which includes the following steps: A transverse drilling operation is performed on the copper plate 100 to form an overflow prevention flow channel 103 on the top surface of the copper plate, wherein the overflow prevention flow channel 103 is connected to the overflow prevention groove 102.

[0049] In this embodiment, when a thicker prepreg board 300 is used for lamination, even if some of the adhesive flows into the anti-overflow groove 102 when the prepreg board 300 fuses to form an adhesive, it will still overflow along the side wall of the boss 110 after the anti-overflow groove 102 is saturated with adhesive. Therefore, a transverse drilling operation is performed on the copper plate 100 to form an anti-overflow flow channel 103 on the top surface of the copper plate. This allows more adhesive to flow into the anti-overflow groove 102 and the anti-overflow flow channel 103 when the copper plate 100, the prepreg board 300 and the double-sided board 200 are subsequently laminated, thereby reducing the situation where adhesive overflows along the side wall of the boss 110, ensuring the electrical performance and long-term reliability of the circuit board during subsequent use, and reducing the defect rate of circuit board production.

[0050] Furthermore, such as Figure 6 As shown, a transverse drilling operation is performed on the copper plate 100, followed by the following steps: Multiple transverse drilling operations are performed on the boss 110 to form multiple spaced-apart hierarchical flow channels 111 within the boss 110.

[0051] It is understandable that when a thicker prepreg plate 300 is used for lamination, even if some of the adhesive flows into the anti-overflow groove 102 when the prepreg plate 300 fuses to form an adhesive, some adhesive will still overflow along the side wall of the boss 110 after the adhesive in the anti-overflow groove 102 and the anti-overflow flow channel 103 becomes saturated. Therefore, a transverse drilling operation is performed on the copper plate 100 to form multiple spaced-apart hierarchical flow channels 111 in the boss 110. In this way, after the adhesive in the anti-overflow groove 102 and the anti-overflow flow channel 103 becomes saturated, some adhesive will try to overflow along the side wall of the boss 110. However, due to the multiple spaced-apart hierarchical flow channels 111, some adhesive fills the hierarchical flow channels 111 from bottom to top, thereby playing a multi-level role in preventing adhesive overflow. In a preferred embodiment, the number of hierarchical flow channels 111 is two, so that in the lamination step, the anti-overflow flow channel 103 and the two hierarchical flow channels 111 constitute a three-level anti-adhesive overflow structure.

[0052] This disclosure also provides a circuit board manufactured using any of the circuit board lamination methods described in the above embodiments.

[0053] Compared with the prior art, this disclosure has at least the following advantages: During circuit board production, double-sided boards 200 and prepreg boards 300 are drilled with holes. Then, copper boards 100, prepreg boards 300, and double-sided boards 200 are assembled. A boss 110 on the top surface of the copper board 100 passes through the second routing groove 301 and the first routing groove 201, and the boss 110 extends from the top surface of the double-sided board 200, thus forming a board to be pressed. Then, a molding film 400 is applied to both sides of the board to be pressed to cover the top surface of the boss 110, the double-sided board 200, and the copper board 100. Before pressing, the width of the first routing groove 201 is smaller than that of the second routing groove 301. During the lamination process, the prepreg 300 melts to form a colloid. Since the top surface of the boss 110 is covered by the molding film 400, the stress on the double-sided panel 200 caused by the downward pressure of the steel plate decreases. Consequently, the colloid formed by the melting of the prepreg 300 has some space to flow towards the corner between the boss 110 and the copper plate 100, filling the gap between the double-sided panel 200 and the copper plate 100. Furthermore, the colloid is less likely to overflow onto the top surface of the boss 110, ensuring the electrical performance and long-term reliability of the circuit board during subsequent use, as well as ensuring the production efficiency of the circuit board.

[0054] The embodiments described above are merely illustrative of several implementations of this disclosure, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the disclosed patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this disclosure, and these all fall within the protection scope of this disclosure. Therefore, the protection scope of this patent should be determined by the appended claims.

Claims

1. A method for laminating and manufacturing a circuit board, characterized in that, Includes the following steps: S101. Perform a controlled-depth etching step on the copper plate to create a boss on the top surface of the copper plate. S102. Apply dry film to the top surface of the double-sided board and form the circuit on the bottom surface of the double-sided board. S103. Perform a milling operation on the double-sided panel to give the double-sided panel a first milling groove; S104. Perform a milling operation on the prepreg to give the prepreg a second milling groove, wherein the first milling groove is connected to the second milling groove. S105. The double-sided panel, the semi-cured board and the copper plate are stacked to form a board to be pressed together, wherein the boss is sequentially inserted into the second groove and the first groove, and the boss protrudes from the top surface of the double-sided panel, and the width of the first groove is smaller than the width of the second groove. S106. Apply a molding film to the upper and lower surfaces of the plate to be pressed. S107. The plate to be pressed after the cover film is applied is pressed to form a pressed plate.

2. The circuit board lamination manufacturing method according to claim 1, characterized in that, After executing S101 and before executing S102, the following steps are included: A drilling operation is performed on the copper plate to give the copper plate a first rivet hole.

3. The circuit board lamination manufacturing method according to claim 2, characterized in that, After executing S103 and before executing S104, the following steps are included: A drilling operation is performed on the prepreg to give the prepreg a second rivet hole, wherein the first rivet hole and the second rivet hole are connected.

4. The circuit board lamination manufacturing method according to claim 3, characterized in that, After executing S102 and before executing S103, the following steps are included: A drilling operation is performed on the double-sided panel to give the double-sided panel a third rivet hole, wherein the third rivet hole, the second rivet hole, and the first rivet hole are sequentially connected.

5. The circuit board lamination manufacturing method according to claim 4, characterized in that, The execution of S105 includes the following steps: The double-sided panel, the semi-cured board, and the copper plate are stacked using rivets to form a board to be pressed together. The boss is sequentially inserted into the second groove and the first groove, and the boss extends from the top surface of the double-sided panel. The rivets are sequentially inserted into the third rivet hole, the second rivet hole, and the first rivet hole.

6. The circuit board lamination manufacturing method according to claim 5, characterized in that, The length of the rivet is equal to the sum of the depths of the first rivet hole, the second rivet hole, and the third rivet hole.

7. The circuit board lamination manufacturing method according to claim 6, characterized in that, The width of the first groove is 2-3 mil larger than the width of the boss.

8. The circuit board lamination manufacturing method according to claim 6, characterized in that, The width of the second groove is 6-8 mil larger than the width of the boss.

9. The circuit board lamination manufacturing method according to claim 1, characterized in that, The height of the boss is greater than the total thickness of the double-sided panel and the prepreg, and the height of the boss is 10-15μm.

10. A circuit board, characterized in that, It is manufactured using the circuit board lamination method as described in any one of claims 1 to 9.

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