Circuit Board and its Lamination Manufacturing Method

Abstract

This disclosure provides a circuit board and a method for laminating the same. The method includes: performing a controlled-depth etching step on a copper plate to form bosses on the top surface of the copper plate; applying a dry film to the top surface of a double-sided board and forming circuits on the bottom surface of the double-sided board; performing a routing operation on the double-sided board to form a first routing groove; performing a routing operation on a prepreg board to form a second routing groove, wherein the first routing groove and the second routing groove are connected; stacking the double-sided board, the prepreg board, and the copper plate to form a board to be laminated, wherein the bosses extend from the top surface of the double-sided board; applying a molding film to both the top and bottom surfaces of the board to be laminated; and laminating the board after applying the molding film to form a laminated board. Because the top surface of the bosses is covered by the molding film, the adhesive formed by the melting of the prepreg board will not overflow to the top surface of the bosses, ensuring the electrical performance and long-term reliability of the circuit board during subsequent use and ensuring the production efficiency of the circuit board.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of circuit boards, in particular to a circuit board and a press-bonding manufacturing method thereof. BACKGROUND

[0002] PCB is an important electronic component, which is the support of electronic components and the carrier of electrical connection of electronic components. The copper-embedded aluminum boss belongs to a kind of metal PCB board parts, which can be applied to the processing technical field of high-power industrial, lighting and automobile circuit boards in the parts assembled with switching elements and power supply, power amplifier elements.

[0003] The existing circuit board production scheme, such as the copper-based printed circuit board with a boss and a processing method thereof disclosed in Chinese patent CN113260139A, has a boss on the copper plate, and then the semi-cured plate and the layer plate are sequentially placed and press-bonding operation is performed. However, during the press-bonding process, the PP plate forms PP glue due to high temperature, and some PP glue will overflow to the surface of the boss, resulting in damage to the electrical performance of the circuit board during subsequent use and a decrease in long-term reliability. The existence of the above problems also requires rework processing, which affects the production efficiency of the circuit board. SUMMARY

[0004] The purpose of the present disclosure is to overcome the deficiencies in the prior art and provide a circuit board and a press-bonding manufacturing method thereof which effectively prevent glue overflow and ensure the production quality of the circuit board.

[0005] The purpose of the present disclosure is achieved by the following technical solutions:

[0006] A press-bonding manufacturing method of a circuit board, comprising the following steps:

[0007] S101, performing a controlled-depth etching step on a copper plate to process a boss on the top surface of the copper plate;

[0008] S102, performing a dry film pasting operation on the top surface of a double-sided plate and forming a circuit on the bottom surface of the double-sided plate;

[0009] S103, performing a hole drilling operation on the double-sided plate to make the double-sided plate have a first hole groove;

[0010] S104, performing a hole drilling operation on a semi-cured plate to make the semi-cured plate have a second hole groove, wherein the first hole groove and the second hole groove are in communication;

[0011] S105, performing a plate stacking operation on the double-sided plate, the semi-cured plate and the copper plate to form a to-be-press-bonded plate, wherein the boss is sequentially arranged in the second hole groove and the first hole groove, the boss protrudes from the top surface of the double-sided plate, and the width of the first hole groove is smaller than the width of the second hole groove;

[0012] S106, pasting a cover film on the upper and lower surfaces of the to-be-laminated board;

[0013] S107, laminating the to-be-laminated board after pasting the cover film to form a laminated board.

[0014] In one of the embodiments, after S101 is performed and before S102 is performed, the following step is included: drilling the copper plate to have a first rivet hole.

[0015] In one of the embodiments, after S103 is performed and before S104 is performed, the following step is included: drilling the prepreg to have a second rivet hole, wherein the first rivet hole and the second rivet hole are in communication.

[0016] In one of the embodiments, after S102 is performed and before S103 is performed, the following step is included: drilling the double-sided board to have a third rivet hole, wherein the third rivet hole, the second rivet hole and the first rivet hole are in sequence.

[0017] In one of the embodiments, when S105 is performed, the following steps are specifically included:

[0018] stacking the double-sided board, the prepreg and the copper plate by the rivet to form a to-be-laminated board, wherein the boss is sequentially arranged in the second groove and the first groove, and the boss protrudes from the top surface of the double-sided board, and the rivet is sequentially arranged in the third rivet hole, the second rivet hole and the first rivet hole.

[0019] In one of the embodiments, 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.

[0020] In one of the embodiments, the width of the first groove is 2-3 mil larger than the width of the boss.

[0021] In one of the embodiments, the width of the second groove is 6-8 mil larger than the width of the boss.

[0022] In one of the embodiments, the height of the boss is greater than the total thickness of the double-sided board and the prepreg, and the height of the boss is 10-15 μm.

[0023] A circuit board is made by the circuit board laminating manufacturing method in any of the above embodiments.

[0024] Compared with the prior art, the present disclosure has at least the following advantages:

[0025] 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

[0026] 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.

[0027] Figure 1 This is a flowchart of a circuit board lamination manufacturing method in one embodiment;

[0028] Figure 2 This is a cross-sectional view of the circuit board before assembly in one embodiment;

[0029] Figure 3 for Figure 2 The diagram shown is a cross-sectional view of the assembled circuit board.

[0030] Figure 4 for Figure 2 The diagram shows a cross-sectional view of the circuit board shown.

[0031] Figure 5 This is a cross-sectional view of the copper plate of the circuit board in another embodiment;

[0032] Figure 6 This is a cross-sectional view of the copper plate of the circuit board in another embodiment.

[0033] 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

[0034] For the purpose of promoting an understanding of the disclosure, the present disclosure will now be described in greater detail with reference to the figures. The preferred embodiments of the present disclosure are illustrated in the figures. However, the present disclosure can be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and fully convey the scope of the disclosure to those skilled in the art.

[0035] It should be noted that when an element is referred to as being "on" another element, it can be directly on the other element or intervening elements can also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements can also be present. The terms "vertical", "horizontal", "left", "right", and the like as used herein are used for illustration only and are not intended to limit the present disclosure.

[0036] 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 in the description of the disclosure herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0037] In order to better understand the technical solutions and beneficial effects of the present disclosure, the present disclosure will be further described in detail below in combination with specific embodiments:

[0038] Please refer to Figure 1 , which is a circuit board pressing manufacturing method according to an embodiment of the present disclosure, comprising the following steps:

[0039] S101, a depth-controlled etching step is performed on the copper plate 100 to process 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 through a depth-controlled etching step to control the etching depth of the copper plate 100, so as to process a boss 110 on the top surface of the copper plate 100, as shown in the effect diagram Figure 2 .

[0040] S102, dry film lamination is performed on the top surface of the double-sided board 200, and a circuit is formed on the bottom surface of the double-sided board 200 to prevent the double-sided board 200 from being etched in the subsequent micro-etching step.

[0041] S103, a hole drilling operation is performed on the double-sided board 200 to make the double-sided board 200 have a first hole groove 201, so as to make a preliminary preparation for the boss 110 on the copper plate 100 to pass through the first hole groove 201 during subsequent assembly.

[0042] S104, a drilling operation is performed on the prepreg 300 to make the prepreg 300 have a second drilled groove 301, wherein the first drilled groove 201 and the second drilled groove 301 are communicated, and also make a preparation for the boss 110 on the copper plate 100 to sequentially pass through the second drilled groove 301 and the first drilled groove 201 in subsequent assembly, and the specific structure is as shown in Figure 2 .

[0043] S105, a laminating operation is performed on the double-sided plate 200, the prepreg 300 and the copper plate 100 to form a to-be-pressed plate, wherein the boss 110 is sequentially arranged in the second drilled groove 301 and the first drilled groove 201, and the boss 110 protrudes from the top surface of the double-sided plate 200, and the width of the first drilled groove 201 is smaller than the width of the second drilled groove 301.

[0044] S106, a cover film 400 is attached to the upper and lower surfaces of the to-be-pressed plate to cover the top surface of the boss 110, and the structure diagram is as shown in Figure 3 .

[0045] S107, a pressing step is performed on the to-be-pressed plate after the cover film 400 is attached to form a pressed plate, wherein the double-sided plate 200 and the copper plate 100 are bonded by the colloid formed by melting of the prepreg 300.

[0046] In this embodiment, as shown in Figure 2 , the width of the first drilled groove 201 is smaller than the width of the second drilled groove 301. It can be understood that the second drilled groove 301 is formed in the prepreg 300, and the first drilled groove 201 is formed in the double-sided plate 200. The prepreg 300 melts during the pressing process to form a colloid with fluidity, so that the double-sided plate 200 and the copper plate 100 are bonded by the colloid. Since the width of the first drilled groove 201 is smaller than the width of the second drilled groove 301, the amount of the colloid formed by melting of the prepreg 300 is controlled, and the colloid formed by melting of the prepreg 300 has enough space to flow to the corner between the boss 110 and the top surface of the copper plate 100, so as to prevent the colloid from overflowing on the surface of the double-sided plate 200, and also reduce the amount of the colloid overflowing on the side wall of the boss 110.

[0047] After the pressing step is completed, the corresponding effect diagram is as shown in Figure 4 .

[0048] In the above embodiment, when producing the circuit board, the double-sided board 200 and the prepreg 300 are drilled, and then the copper plate 100, the prepreg 300 and the double-sided board 200 are assembled, wherein the boss 110 on the top surface of the copper plate 100 passes through the second drill slot 301 and the first drill slot 201, and the boss 110 extends from the top surface of the double-sided board 200, thereby forming a to-be-pressed board, and then the cover film 400 is attached to both surfaces of the to-be-pressed board 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 drill slot 201 is smaller than the width of the second drill slot 301. In the pressing step, the prepreg 300 melts to form a glue, and because the top surface of the boss 110 is covered by the cover film 400, the stress of the double-sided board 200 under the pressing of the steel plate is reduced, and the glue formed by the melting of the prepreg 300 has a certain space to flow to the corner between the boss 110 and the copper plate 100, fills the gap between the double-sided board 200 and the copper plate 100, and the glue is less likely to overflow to the top surface of the boss 110, thereby ensuring the electrical performance and long-term reliability of the circuit board in subsequent use, and ensuring the production efficiency of the circuit board.

[0049] In one embodiment, after S101 is performed and before S102 is performed, the following step is included: drilling the copper plate 100 to have a first rivet hole 101, so as to prepare for the subsequent assembly of the copper plate 100, the prepreg 300 and the double-sided board 200 into a pre-pressed board by the rivet 500 passing through the rivet holes. Figure 2

[0050] Further, after S103 is performed and before S104 is performed, the following step is included: drilling the prepreg 300 to have a second rivet hole 302, wherein the first rivet hole 101 and the second rivet hole 302 are in communication, so as to prepare for the subsequent assembly of the copper plate 100, the prepreg 300 and the double-sided board 200 into a pre-pressed board by the rivet 500 passing through the rivet holes. Figure 2

[0051] Further, after S102 is performed and before S103 is performed, the following step is included: drilling the double-sided board 200 to have a third rivet hole 202, wherein the third rivet hole 202, the second rivet hole 302 and the first rivet hole 101 are in sequence, so as to prepare for the subsequent assembly of the copper plate 100, the prepreg 300 and the double-sided board 200 into a pre-pressed board by the rivet 500 passing through the third rivet hole 202, the second rivet hole 302 and the first rivet hole 101, that is, by drilling the copper plate 100, the prepreg 300 and the double-sided board 200 to facilitate the assembly by the rivet 500 passing through the corresponding rivet holes in the subsequent steps. Figure 2 and​​Figure 3 as shown.

[0052] Further, the step S105 is specifically implemented as follows:

[0053] The double-sided panel 200, the prepreg panel 300 and the copper panel 100 are laminated by the rivet 500 to form a to-be-pressed panel, wherein the boss 110 is sequentially arranged in 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 rivet 500 is sequentially arranged in the third rivet hole 202, the second rivet hole 302 and the first rivet hole 101. In this embodiment, before the double-sided panel 200, the prepreg panel 300 and the copper panel 100 are fixed by the rivet 500, the double-sided panel 200, the prepreg panel 300 and the copper panel 100 need to be drilled to facilitate the rivet 500 to pass through the corresponding rivet hole to fix the double-sided panel 200, the prepreg panel 300 and the copper panel 100. Specifically, in the assembling step, the double-sided panel 200, the prepreg panel 300 and the copper panel 100 are sequentially laminated, and then the rivet 500 is used to sequentially pass through the third rivet hole 202, the second rivet hole 302 and the first rivet hole 101 to fix the double-sided panel 200, the prepreg panel 300 and the copper panel 100, so as to prevent one or two of them from deviating, thereby forming the to-be-pressed panel, wherein the boss 110 on the copper panel 100 protrudes from the top surface of the double-sided panel 200 after passing through the second groove 301 and the first groove 201, so as to facilitate the subsequent use of the cover film 400 to cover the top of the boss 110, that is, the cover film 400 is in contact with the top of the boss 110. In addition, after the step S106, the cover film 400 is attached to both sides of the to-be-pressed panel, on one hand, in the pressing step, the prepreg panel 300 melts to form a glue, and the cover film 400 can prevent the glue from overflowing on the top of the boss 110, on the other hand, in the pressing step, the steel plate is used for pressing, and the cover film 400 covers the bottom surface of the to-be-pressed panel, that is, one surface of the copper panel 100, and covers the rivet 500, so as to prevent the rivet 500 from damaging the steel plate of the pressing machine.

[0054] Further, after the step S107, the following steps are included:

[0055] The to-be-pressed panel is subjected to a film removing operation to remove the cover film 400.

[0056] The to-be-pressed panel is subjected to a polishing operation to make the height of the boss 110 equal to the sum of the heights of the double-sided panel 200 and the prepreg panel 300.

[0057] In the present embodiment, after the cover type film 400 is attached to both sides of the to-be-laminated board, the laminating step is performed, during which the cover type film 400 is always in contact with the top surface of the boss 110 to prevent the melted PP glue from overflowing to the top surface of the boss 110, and after the lamination is completed, the laminated board is formed, and then the film removing operation is performed to remove the cover type film 400, thereby facilitating the subsequent step execution, and then the polishing operation is performed to make the height of the boss 110 equal to the sum of the heights of the double-sided board 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 board 200, thereby ensuring the flatness of the surface of the laminated board. In addition, during the lamination process, the glue formed by melting the prepreg board 300 will overflow from the gap between the sidewall of the boss 110 and the double-sided board 200, and part of the glue is located on the sidewall of the boss 110. Therefore, through the polishing operation, not only the top surface of the boss 110 is flush with the top surface of the double-sided board 200, but also the overflowed glue can be effectively removed, ensuring the cleanliness of the boss 110, that is, the top surface of the boss 110 can be fully exposed, facilitating the electrical connection of the subsequent circuit board, and thus ensuring the electrical performance of the circuit board during subsequent use.

[0058] It should be noted that when performing S105, it is necessary to ensure that the boss 110 protrudes from the top surface of the double-sided panel 200, that is, the height of the boss 110 must be higher than the sum of the heights of the double-sided panel 200 and the prepreg 300, so that when the cover film 400 is attached to the copper plate 100, it can be in contact with the top surface of the boss 110. In this way, when the pressing operation is performed, the prepreg 300 melts due to the temperature rise to form a colloid with fluidity, and the colloid may overflow from the gap between the double-sided panel 200 and the side wall of the boss 110. The top surface of the boss 110 is in contact with the cover film 400, so that the cover film 400 covers the top surface of the boss 110, so that the colloid does not overflow to the top surface of the boss 110. When the double-sided panel 200, the prepreg 300 and the copper plate 100 are assembled, if the height of the boss 110 is lower than the sum of the heights of the double-sided panel 200 and the prepreg 300, a groove is formed between the top surface of the boss 110 and the first groove 201 of the double-sided panel 200. In this way, in the pressing step, the prepreg 300 melts to form a colloid, and the colloid inevitably overflows on the top surface of the boss 110, even filling the above-mentioned groove, so that the top surface of the boss 110 cannot be exposed to the outside, which is not convenient for subsequent film removal and polishing operations. When the double-sided panel 200, the prepreg 300 and the copper plate 100 are assembled, if the height of the boss 110 is equal to the sum of the heights of the double-sided panel 200 and the prepreg 300, the top surface of the boss 110 is flush with the top surface of the double-sided panel 200. Similarly, in the pressing step, the colloid inevitably overflows on the top surface of the boss 110, which destroys the neatness of the top surface of the boss 110. In the subsequent polishing operation, even if the colloid on the top surface of the boss 110 can be removed, the flatness of the already pressed plate is destroyed. The above two cases will be detrimental to the production process of the circuit board, and it is difficult to ensure the electrical performance and long-term reliability of the circuit board. Therefore, when the double-sided panel 200, the prepreg 300 and the copper plate 100 are assembled, it is necessary to ensure that the boss 110 protrudes from the top surface of the double-sided panel 200.

[0059] It should be noted that the pressing step is performed by the steel plate of the pressing device, if S107 is performed first and S106 is performed later, during the pressing process, the semi-cured plate 300 melts to form a glue, which makes the thickness of the semi-cured plate 300 change, part of the glue will overflow along the side wall and top surface of the boss 110, and when there is too much glue, it will also submerge the top surface of the boss 110, and at the same time, without the cover film 400, due to the change of the thickness of the semi-cured plate 300, the overall thickness of the to-be-pressed plate changes, at this time, the two ends of the rivet 500 are exposed outside the to-be-pressed plate, which will also cause the steel plate to be pressed by the rivet 500, in order to ensure the production quality of the circuit board, before the pressing step, the cover film 400 is pasted on both sides of the to-be-pressed plate, and then the pressing operation is performed, so as to reduce the probability of the glue formed by the melting of the semi-cured plate 300 overflowing to the top surface of the boss 110 during the pressing process, and also reduce the probability of the rivet 500 pressing the steel plate during the pressing process.

[0060] Further, the to-be-pressed plate is polished, specifically, the polishing is performed by ceramic, so that the height of the boss 110 is equal to the sum of the heights of the double-sided plate 200 and the semi-cured plate 300.

[0061] Further, the width of the first slot 201 is greater than the width of the boss 110 by 2-3 mil (50.8-76.2 μm).

[0062] Further, the width of the second slot 301 is greater than the width of the boss 110 by 6-8 mil (152.4-203.2 μm). In this way, when the double-sided plate 200, the semi-cured plate 300 and the copper plate 100 are assembled, since there is a certain distance (referred to as a first distance) between the first slot 201 and the side wall of the boss 110, and there is a certain distance (referred to as a second distance) between the second slot 301 and the side wall of the boss 110, and the first distance is greater than the second distance, the amount of glue formed by the melting of the semi-cured plate 300 overflowing from the first slot 201 and the side wall of the boss 110 is controlled, at the same time, the width of the second slot 301 is greater than the width of the boss 110 by 6-8 mil, which makes there be enough space between the copper plate 100 and the double-sided plate 200 for the glue to fill, so that the copper plate 100 and the double-sided plate 200 are fully filled with copper glue, which reduces the probability of the glue overflowing on the top surface of the double-sided plate 200.

[0063] In one embodiment, the height of the boss 110 protruding from the top surface of the double-sided panel 200 is 10-15 μm. It can be understood that the height of the top of the boss 110 protruding from the top surface of the double-sided panel 200 reaches the micron level, which does not make the surface of the to-be-laminated panel too conspicuous as a whole, and after the cover film 400 is attached, the cover film 400 is in contact with the top surface of the boss 110, and in the lamination step, the adhesive does not overflow to the top surface of the boss 110, thereby ensuring the cleanliness of the top surface of the boss 110, and in the subsequent polishing step, the top surface of the boss 110 can be polished to make the top surface of the boss 110 flush with the top surface of the double-sided panel 200, and the overflowed adhesive can also be effectively removed, so that the top surface of the boss 110 is fully exposed on the surface of the double-sided panel 200, facilitating subsequent processes.

[0064] 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 300, and the copper plate 100 can be effectively assembled and fixed to form a to-be-laminated panel, and then the cover film 400 is attached to both surfaces of the to-be-laminated panel to cover the rivet 500, so that even if the thickness of the prepreg 300 changes in the lamination step, the probability of the rivet 500 pressing the steel plate can be reduced due to the buffering function of the cover film 400.

[0065] Further, the cover film 400 is a three-in-one film having a structure of "PET release film + PE buffer layer + PET release film", 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 laminated during the lamination process.

[0066] In one embodiment, after S101 is performed, the following steps are included:

[0067] The copper plate 100 is subjected to an ablation operation to process an anti-overflow groove 102 on the top surface of the copper plate 100, wherein the anti-overflow groove 102 is arranged at the corner between the top surface of the copper plate 100 and the side wall of the boss 110, and the specific structure is as shown in Figure 5 .

[0068] It can be understood that in the pressing operation, the semi-cured plate 300 melts to form a glue, part of the glue flows along the corner between the top surface of the copper plate 100 and the side wall of the boss 110, and then flows along the side wall of the boss 110 to overflow on the surface of the double-sided plate 200. If the semi-cured plate 300 is too thick, too much glue will be generated during melting. Excess glue, part of the glue flows along the edge of the double-sided plate 200 and the copper plate 100, and part of the glue flows along the side wall of the boss 110 to overflow on the surface of the double-sided plate 200, and the overflow amount is relatively large, which has the risk of part of the glue overflowing on the top surface of the boss 110, thereby increasing the difficulty of removing the glue. In order to prevent too much glue from overflowing on the surface of the double-sided plate 200, after S101, the copper plate 100 is subjected to an ablation operation to form an anti-overflow groove 102, wherein the anti-overflow groove 102 is arranged at the corner between the top surface of the copper plate 100 and the side wall of the boss 110. In the subsequent pressing step, part of the glue formed by melting the semi-cured plate 300 will first fill the anti-overflow groove 102, which makes the glue less likely to overflow on the surface of the double-sided plate 200, thereby reducing the probability of the top surface of the boss 110 being covered by the glue, ensuring the electrical performance and long-term reliability of the circuit board during subsequent use, and reducing the defect rate of the circuit board production.

[0069] Further, as shown in Figure 6 the copper plate 100 is subjected to an ablation operation, and then includes the following steps:

[0070] The copper plate 100 is subjected to a transverse drilling operation to form an anti-overflow flow channel 103 on the top surface of the copper plate, wherein the anti-overflow flow channel 103 communicates with the anti-overflow groove 102.

[0071] In this embodiment, when a relatively thick semi-cured plate 300 is used for pressing, part of the glue will flow into the anti-overflow groove 102 when the semi-cured plate 300 melts to form glue, but the glue will still overflow along the side wall of the boss 110 when the anti-overflow groove 102 is saturated. Therefore, the copper plate 100 is subjected to a transverse drilling operation to form an anti-overflow flow channel 103 on the top surface of the copper plate, so that more glue will flow into the anti-overflow groove 102 and the anti-overflow flow channel 103 when the copper plate 100, the semi-cured plate 300 and the double-sided plate 200 are pressed subsequently, thereby reducing the overflow of the glue 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 the circuit board production.

[0072] Further, as shown in Figure 6 the copper plate 100 is subjected to a transverse drilling operation, and then includes the following steps:

[0073] The boss 110 is subjected to a plurality of transverse drilling operations to form a plurality of spaced hierarchical flow channels 111 in the boss 110.

[0074] It can be understood that when the thicker prepreg 300 is used for pressing, the prepreg 300 melts to form a glue body, even if part of the glue body flows into the anti-overflow groove 102, when the glue body in the anti-overflow groove 102 and the anti-overflow flow channel 103 is saturated, part of the glue body still overflows along the side wall of the boss 110. Therefore, the copper plate 100 is transversely drilled to form a plurality of spaced hierarchical flow channels 111 in the boss 110. In this way, when the glue body in the anti-overflow groove 102 and the anti-overflow flow channel 103 is saturated, part of the glue body tries to overflow along the side wall of the boss 110, but because a plurality of spaced hierarchical flow channels 111 are arranged, part of the glue body fills the hierarchical flow channels 111 from bottom to top, thereby playing a role in preventing the glue body from overflowing in multiple stages. In an optimal embodiment, the number of hierarchical flow channels 111 is 2, so that in the pressing step, the anti-overflow flow channel 103 and the two hierarchical flow channels 111 form a three-stage anti-overflow structure.

[0075] The present disclosure also provides a circuit board made by the circuit board pressing manufacturing method of any one of the above embodiments.

[0076] Compared with the prior art, the present disclosure has at least the following advantages:

[0077] In the production of a circuit board, the double-sided plate 200 and the prepreg 300 are drilled, and then the copper plate 100, the prepreg 300, and the double-sided plate 200 are assembled, wherein the boss 110 on the top surface of the copper plate 100 passes through the second drill groove 301 and the first drill groove 201, and the boss 110 protrudes from the top surface of the double-sided plate 200, thereby forming a to-be-pressed plate. Then, a cover film 400 is attached to both surfaces of the to-be-pressed plate to cover the top surface of the boss 110, the double-sided plate 200, and the copper plate 100. Before pressing, the width of the first drill groove 201 is smaller than the width of the second drill groove 301. In the pressing step, the prepreg 300 melts to form a glue body. Because the top surface of the boss 110 is covered by the cover film 400, the stress on the double-sided plate 200 caused by the pressing of the steel plate is reduced, and the glue body formed by the melting of the prepreg 300 has a certain space to flow to the corner between the boss 110 and the copper plate 100, thereby filling the gap between the double-sided plate 200 and the copper plate 100, and the glue body is less likely to overflow to the top surface of the boss 110, thereby ensuring the electrical performance and long-term reliability of the circuit board in subsequent use, and ensuring the production efficiency of the circuit board.

[0078] The above embodiments only express several embodiments of the present disclosure, and the description is more specific and detailed, but it cannot be understood as a limitation on the scope of the disclosed patent. It should be noted that for ordinary skilled persons in the art, without departing from the concept of the present disclosure, a number of modifications and improvements can be made, which are within the scope of protection of the present disclosure. Therefore, the protection scope of the present disclosure patent should be subject to the appended claims.

Claims

1. A method of manufacturing a circuit board by pressing, characterized by, The method comprises the following steps: S101, performing a depth control etching step on the copper plate to process a boss on the top surface of the copper plate; S101A, performing an ablation operation on the copper plate to process an anti-overflow groove on the top surface of the copper plate, wherein the anti-overflow groove is arranged at the corner between the top surface of the copper plate and the side wall of the boss; S101B, performing a transverse drilling operation on the copper plate to form an anti-overflow flow channel on the top surface of the copper plate, wherein the anti-overflow flow channel communicates with the anti-overflow groove; S101C, performing a plurality of transverse drilling operations on the boss to form a plurality of spaced hierarchical flow channels in the boss; S102, performing a dry film pasting operation on the top surface of the double-sided plate, and forming a circuit on the bottom surface of the double-sided plate; S103, performing a hole drilling operation on the double-sided plate to make the double-sided plate have a first milling groove; S104, performing a hole drilling operation on the prepreg to make the prepreg have a second milling groove, wherein the first milling groove communicates with the second milling groove; S105, performing a plate stacking operation on the double-sided plate, the prepreg and the copper plate to form a to-be-pressed plate, wherein the boss is sequentially arranged in the second milling groove and the first milling groove, and the boss protrudes from the top surface of the double-sided plate, the width of the first milling groove is smaller than the width of the second milling groove; S106, pasting a cover film on the upper and lower surfaces of the to-be-pressed plate, wherein the cover film is a three-in-one film, and the cover film has a structure of "PET release film+PE buffer layer+PET release film"; S107, performing a pressing step on the to-be-pressed plate with the cover film pasted thereon to form a pressed plate; The number of hierarchical flow channels is two, so that the anti-overflow flow channel and the two hierarchical flow channels form a three-level anti-overflow structure in the pressing step.

2. The method of claim 1, wherein After S101 is performed and before S102 is performed, the following steps are included: Performing a hole drilling operation on the copper plate to make the copper plate have a first rivet hole.

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

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

5. The circuit board lamination manufacturing method according to claim 4, characterized in that, When S105 is performed, the following steps are included: Performing a plate stacking operation on the double-sided plate, the prepreg and the copper plate by means of a rivet to form a to-be-pressed plate, wherein the boss is sequentially arranged in the second milling groove and the first milling groove, and the boss protrudes from the top surface of the double-sided plate, and the rivet is sequentially arranged in the third rivet hole, the second rivet hole and the first rivet hole.

6. The method of claim 5, wherein 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 method according to claim 6, wherein The width of the first milling 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 milling groove is 6-8 mil larger than the width of the boss.

9. The method of claim 1, wherein The height of the convex is greater than the total thickness of the double-sided board and the prepreg, and the height of the convex is 10-15 μm.

10. A wiring board, characterized by The circuit board is manufactured by the method of claim 1 to 9.

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