Method for manufacturing thick copper circuit board and thick copper circuit board

Abstract

The embodiment of the invention provides a method for manufacturing a thick copper circuit board and the thick copper circuit board. The method comprises the steps that a first copper foil with the thickness larger than a preset threshold value is bonded to a carrier plate through a viscous substance; a groove is formed in one side, deviating from the carrier plate, of the first copper foil; the side, attached with the first copper foil, of the carrier plate and a printed circuit board are subjected to relative press fit, the sticky substance loses stickiness in the press fit process, the printed circuit board comprises multiple layers of second copper foil, and the thickness of the second copper foil is smaller than or equal to the preset threshold value; and stripping the carrier plate from the printed circuit board to obtain the thick copper circuit board. The method is used for achieving the effect of improving the yield of the thick copper circuit board.

Description

Technical Field

[0001] This application relates to the field of circuit board manufacturing technology, and in particular to a method for manufacturing a thick copper circuit board and the thick copper circuit board itself. Background Technology

[0002] With the advent of the 5G communication era, the application of high-power electronic components such as high-frequency radio frequency and power amplifiers is becoming increasingly common, thus placing higher demands on the heat dissipation capabilities of printed circuit boards (PCBs). Existing technology effectively solves the heat dissipation problem of high-power electronic components by embedding copper blocks inside the PCB. Copper blocks possess high thermal conductivity, high heat dissipation, and space-saving properties, thus effectively addressing the heat dissipation issue of high-power electronic components. However, as the package size of assembled components becomes smaller, the requirements for the size of PCBs also decrease. This has led to the development of thick copper PCBs, which are PCBs that use copper foil with a greater thickness on the outer layer than the inner copper foil layer.

[0003] Currently, the manufacturing method for thick copper circuit boards involves directly etching a copper foil thicker than the inner copper foil, and then laminating the etched copper foil onto the printed circuit board. Because the copper foil is very thin, direct processing of the copper foil can easily damage it, such as causing scratches, indentations, or curling. This can not only affect the performance of the printed circuit board, but may even directly cause the copper foil processing to fail. Summary of the Invention

[0004] This application provides a method for manufacturing a thick copper circuit board and a thick copper circuit board, which can reduce the risk of failure during copper foil processing.

[0005] In a first aspect, embodiments of this application provide a method for manufacturing a thick copper circuit board, comprising:

[0006] A first copper foil with a thickness greater than a preset threshold is bonded to a carrier plate using an adhesive substance;

[0007] A groove is made on the side of the first copper foil that is away from the carrier plate;

[0008] The side of the carrier board with the first copper foil attached is pressed against the printed circuit board, wherein the adhesive material loses its adhesiveness during the pressing process, and the printed circuit board includes multiple layers of second copper foil, the thickness of the second copper foil being less than or equal to the preset threshold.

[0009] The carrier board is peeled off from the laminated printed circuit board to obtain a thick copper circuit board.

[0010] In one possible implementation, before pressing the side of the carrier board with the first copper foil attached to the printed circuit board against each other, the method further includes:

[0011] The carrier plate with the first copper foil bonded to it is riveted and fixed to the printed circuit board.

[0012] In one possible implementation, riveting and fixing the carrier board with the first copper foil to the printed circuit board includes:

[0013] A first through hole is made in the area of ​​the carrier plate not covered by the first copper foil;

[0014] A second through hole is formed on the printed circuit board, and the second through hole is adapted to the first through hole;

[0015] A connecting component is used to pass through the first through hole and the second through hole to rivet and fix the carrier board with the first copper foil to the printed circuit board.

[0016] In one possible implementation, riveting and fixing the carrier board with the first copper foil to the printed circuit board includes:

[0017] At least one positioning hole is made in the area of ​​the carrier plate not covered by the first copper foil;

[0018] At least one fixing pin is made on the printed circuit board, and the fixing pin corresponds one-to-one with the positioning hole;

[0019] Each of the fixing pins is inserted into the corresponding positioning hole to rivet and fix the carrier plate with the first copper foil to the printed circuit board.

[0020] In one possible implementation, after peeling the carrier board from the laminated printed circuit board, the process further includes:

[0021] The area of ​​the printed circuit board that does not overlap with the first copper foil is removed to obtain the thick copper circuit board.

[0022] In one possible implementation, the side of the carrier board with the first copper foil attached is pressed against the printed circuit board, including:

[0023] The side of the carrier board with the first copper foil attached is pressed against the printed circuit board at a second preset temperature; the second preset temperature is greater than the first preset temperature.

[0024] In one possible implementation, the viscous substance is viscous in an environment with a temperature lower than a first preset temperature, and loses its viscousness in an environment with a temperature greater than or equal to the first preset temperature.

[0025] In one possible implementation, the first copper foil is adhered to the carrier plate using an adhesive material, including:

[0026] An adhesive is used to bond the front side of the first copper foil to the carrier plate, wherein the front side of the first copper foil is smoother than the back side of the first copper foil.

[0027] In one possible implementation, after obtaining the thick copper circuit board, the following steps are also included:

[0028] Etch lines on the front side of the first copper foil.

[0029] Secondly, this application provides a thick copper circuit board, which is obtained by means of the first aspect and / or various possible embodiments of the first aspect.

[0030] The method and embodiment of this application for manufacturing a thick copper circuit board involve first bonding a first copper foil to a carrier board, and then creating grooves in the first copper foil. This carrier board supports and fixes the first copper foil, preventing damage or deformation during the groove fabrication process, thus improving the yield of the thick copper circuit board. Furthermore, the adhesive between the carrier board and the first copper foil loses its adhesiveness under the high temperature and pressure of lamination, making it easy for the carrier board to separate from the first copper foil. After lamination, the adhesive is less likely to adhere to the first copper foil. Even if it does, it can be removed by grinding, plasma removal, or desmearing after peeling the carrier board from the laminated printed circuit board. This avoids contamination of the first copper foil by the adhesive and ensures the performance of the thick copper circuit board. Attached Figure Description

[0031] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0032] Figure 1 A flowchart illustrating the method for fabricating a thick copper circuit board provided in this application;

[0033] Figure 2(a) is a schematic diagram of the structure obtained by bonding a first copper foil with a size equal to that of the carrier plate to the carrier plate according to the present application;

[0034] Figure 2(b) is a schematic diagram of the structure obtained after a groove is made on the first copper foil according to this application;

[0035] Figure 2(c) is a schematic diagram of a structure obtained by laminating a prepreg and a carrier board with a first copper foil attached on one side of a printed circuit board according to this application.

[0036] Figure 2(d) is a schematic diagram of a structure obtained by riveting and fixing a prepreg and a carrier board to one side of a printed circuit board and then pressing them together, according to the present application.

[0037] Figure 2(e) is a schematic diagram of a structure obtained by laminating a prepreg and a carrier board with a first copper foil on both sides of a printed circuit board according to this application.

[0038] Figure 2(f) is a schematic diagram of a structure obtained by riveting and fixing a prepreg and a carrier board on both sides of a printed circuit board and then pressing them together, according to the present application.

[0039] Figure 2(g) is a schematic diagram of a structure obtained after the prepreg and the carrier board are laminated on one side of a printed circuit board, and the carrier board is removed, according to the present application.

[0040] Figure 2(h) is a schematic diagram of a structure obtained after the prepreg and the carrier board are laminated on both sides of a printed circuit board according to this application and the carrier board is removed.

[0041] Figure 3(a) is a schematic diagram of the structure obtained by bonding a first copper foil with a size smaller than the carrier plate to the carrier plate according to the present application;

[0042] Figure 3(b) is a schematic diagram of another structure obtained after forming a groove on the first copper foil according to this application;

[0043] Figure 3(c) is a schematic diagram of another structure obtained by laminating a prepreg and a carrier board with a first copper foil attached on one side of a printed circuit board, according to this application.

[0044] Figure 3(d) is a schematic diagram of another structure obtained by riveting and fixing the prepreg and the carrier board to one side of the printed circuit board and then pressing them together, according to another application.

[0045] Figure 3(e) is a schematic diagram of another structure obtained by laminating a prepreg and a carrier board with a first copper foil on both sides of a printed circuit board according to this application.

[0046] Figure 3(f) is a schematic diagram of another structure obtained by riveting and fixing the prepreg and the carrier board on both sides of the printed circuit board and then pressing them together, according to this application.

[0047] Figure 3(g) is a schematic diagram of another structure obtained after the prepreg and the carrier board are laminated on one side of the printed circuit board, according to this application, and the carrier board is removed.

[0048] Figure 3(h) is a schematic diagram of another structure obtained by laminating a prepreg and a carrier board on both sides of a printed circuit board, as provided in this application, and then removing the carrier board.

[0049] Reference numerals: 1. Carrier plate; 2. First copper foil; 3. Groove; 4. Second copper foil; 5. Prepreg; 6. Substrate; 7. Printed circuit board; 8. Connecting component.

[0050] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0051] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0052] Existing technology embeds copper blocks inside printed circuit boards (PCBs). Copper blocks, with their high thermal conductivity, high heat dissipation, and space-saving properties, effectively solve the heat dissipation problem of high-power electronic components. However, because the copper block is a single unit, it occupies a large area on the PCB, making it unsuitable for embedding copper blocks on both sides. Furthermore, embedding copper blocks requires pre-grooving the PCB and prepreg, and the manual insertion of the copper block during lamination can lead to adhesive overflow on the copper block and PCB surface, and may also create a height difference between the embedded copper block and the PCB surface, affecting subsequent production processes. This impacts PCB production efficiency and performance. Therefore, embedding copper blocks inside PCBs does not align with the development trends of PCB products towards higher frequencies, miniaturization, thinner profiles, lower power consumption, faster response times, higher resolution, higher precision, higher power, higher frequency, multi-functionality, componentization, composite materials, modularization, and intelligence.

[0053] This led to the development of thick copper circuit boards, which are circuit boards that use copper foil with a greater thickness on the outer layer than the inner copper foil.

[0054] However, the existing solution involves directly etching the copper foil and then pressing the etched copper foil onto the outer surface of the printed circuit board. Since the copper foil is very thin, it is easy to damage the copper foil, thus affecting the performance of the thick copper circuit board.

[0055] Printed circuit boards are made up of multiple layers of inner copper foil and multiple layers of insulating layers. The thickness of the inner copper foil is usually 35 micrometers.

[0056] To address the aforementioned issues, this application provides a method for manufacturing thick copper circuit boards, which involves bonding copper foil onto a carrier before processing the copper foil, thereby reducing the risk of copper foil processing failure and achieving the technical effect of improving the performance of thick copper circuit boards.

[0057] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will now be described with reference to the accompanying drawings.

[0058] Figure 1 A flowchart illustrating the method for fabricating a thick copper circuit board provided in this application is shown below. Figure 1 As shown, the method includes:

[0059] Step S101: Use an adhesive substance to bond a first copper foil with a thickness greater than a preset threshold onto a carrier plate.

[0060] An adhesive substance is a material with adhesive or viscous properties used to bond two or more objects together. In this embodiment, the adhesive substance is used to bond the first copper foil to the carrier plate. Examples of adhesive substances include glue and adhesives.

[0061] The adhesive material is sticky in environments with temperatures below a first preset temperature, but loses its stickiness in environments with temperatures above or equal to the first preset temperature. Therefore, in environments below the first preset temperature, the adhesive material can be used to bond the first copper foil and the carrier board. In environments with temperatures above or equal to the first preset temperature, the bonded first copper foil and carrier board can be peeled off. Thus, the temperature at which the printed circuit board and the carrier board with the first copper foil are pressed together can be determined based on the first preset temperature, thereby achieving the peeling of the first copper foil and the carrier board while pressing the carrier board with the first copper foil onto one side of the printed circuit board. Specifically, the first preset temperature is, for example, 125 degrees Celsius.

[0062] The first copper foil is a copper foil with a thickness greater than a preset threshold. The preset threshold is, for example, 32 micrometers. Specifically, the thickness of the first copper foil is, for example, 105 micrometers.

[0063] Specifically, the compressive strength of the carrier board is greater than a first preset strength, and its decomposition temperature is greater than a third preset temperature. This allows the temperature and pressure for pressing the printed circuit board and the carrier board with the first copper foil attached to it to be determined based on the first preset strength and the third preset temperature, ensuring that the carrier board does not deform while pressing the carrier board with the first copper foil attached onto one side of the printed circuit board. Specifically, epoxy resin can be used as the material for the carrier board.

[0064] In some embodiments, the size of the first copper foil may be the same as or smaller than the size of the carrier plate.

[0065] An adhesive can be used to bond the front side of the first copper foil to the carrier plate, wherein the front side of the first copper foil is smoother than the back side. Because the front side of the first copper foil is smoother than the back side, bonding the front side of the first copper foil to the carrier plate can ensure a tighter bond between the first copper foil and the carrier plate, reducing the possibility of the first copper foil shifting or falling off the carrier plate.

[0066] The adhesive substance can be applied to the entire front surface of the first copper foil, or it can be applied to a portion of the front surface of the first copper foil.

[0067] Step S102: Create a groove on the side of the first copper foil away from the carrier plate.

[0068] Specifically, a specific area on the side of the first copper foil facing away from the carrier board is etched to form grooves, the number of which can be set by the user. This reduces the thickness of the etched area on the first copper foil, while the thickness of the unetched area remains unchanged and still exceeds a preset threshold. Thus, after laminating the first copper foil to the printed circuit board, the copper foil thickness can be increased in areas outside the specific region on the outer layer of the printed circuit board. Compared to directly laminating the first copper foil without grooves to the printed circuit board, this optimizes the cost and performance of thick copper circuit boards.

[0069] Step S103: The carrier board with the first copper foil bonded to it is riveted and fixed to the printed circuit board.

[0070] If the size of the carrier board is equal to the size of the first copper foil, first through holes can be made around the perimeter of the carrier board, with each through hole penetrating the first copper foil. Then, second through holes are made on the printed circuit board, matching the first through holes. Connecting components are then used to pass through both the first and second through holes to rivet and fix the carrier board, to which the first copper foil is bonded, to the printed circuit board. By rivet and fixing the carrier board to the printed circuit board, the carrier board and the first copper foil are less likely to shift during the lamination process, which helps improve the bonding accuracy between the first copper foil and the printed circuit board, thereby improving the performance of the thick copper circuit board.

[0071] If the carrier board size is larger than the first copper foil size, a first through-hole can be made in the area of ​​the carrier board not covered by the first copper foil, and then a second through-hole can be made on the printed circuit board, the second through-hole being adapted to the first through-hole. A connecting component then passes through the first and second through-holes to rivet and fix the carrier board with the first copper foil to the printed circuit board. Alternatively, at least one positioning hole can be made in the area of ​​the carrier board not covered by the first copper foil; then at least one fixing pin can be made on the printed circuit board, each fixing pin corresponding to a positioning hole; finally, each fixing pin is inserted into its corresponding positioning hole to rivet and fix the carrier board with the first copper foil to the printed circuit board. By rivet and fixing the carrier board to the printed circuit board, the carrier board is less prone to shifting during the pressing process, which helps improve the bonding accuracy between the first copper foil and the printed circuit board, thereby improving the performance of the thick copper circuit board. Furthermore, by making the first through-hole or positioning hole in the area of ​​the carrier board not covered by the first copper foil, it is possible to avoid drilling holes in the first copper foil, preventing curling of the first copper foil due to drilling and reducing processing difficulty.

[0072] A connecting component is an assembly used to connect different parts or structures by passing through one or more through holes. Examples of connecting components include bolts and rivets.

[0073] Step S104: The side of the carrier board with the first copper foil attached is pressed against the printed circuit board. During the pressing process, the adhesive material loses its adhesiveness. The printed circuit board includes multiple layers of second copper foil, and the thickness of the second copper foil is less than or equal to a preset threshold.

[0074] If the outermost layer of the printed circuit board is a second copper foil, then a prepreg and a carrier board are sequentially stacked on the second copper foil, and the printed circuit board, prepreg, and carrier board with the first copper foil are pressed together at a second preset temperature. If the outermost layer of the printed circuit board is a prepreg, then the side of the carrier board with the first copper foil and the printed circuit board are directly pressed together at the second preset temperature. The second preset temperature is higher than the first preset temperature and lower than the third preset temperature. In this way, after pressing the carrier board with the first copper foil bonded to it and the printed circuit board together, not only is the carrier board prevented from deforming, but the adhesive between the carrier board and the first copper foil also loses its stickiness.

[0075] Alternatively, a carrier board with the first copper foil bonded to it can be laminated to one side of the printed circuit board to form a single-sided thick copper circuit board. Or, a carrier board with the first copper foil bonded to it can be laminated to both sides of the printed circuit board to form a double-sided mirrored thick copper circuit board.

[0076] Step S105: Peel the carrier board from the laminated printed circuit board to obtain a thick copper circuit board.

[0077] After removing the connecting components, the download board can be removed from the printed circuit board, thus obtaining a thick copper circuit board.

[0078] If the size of the carrier board is equal to the size of the first copper foil, and the size of the printed circuit board in the direction perpendicular to the radial direction is also equal to the size of the first copper foil, then a thick copper circuit board can be directly obtained after peeling the carrier board from the laminated printed circuit board.

[0079] If the carrier board is larger than the first copper foil, and the carrier board is riveted and fixed to the printed circuit board through a first through-hole on the carrier board that does not penetrate the first copper foil, then the printed circuit board's dimension in the radial direction is also larger than the first copper foil's dimension. Therefore, after peeling the carrier board off the laminated printed circuit board, if the first copper foil is to completely cover the top layer of the printed circuit board, the area of ​​the printed circuit board that does not overlap with the first copper foil needs to be removed to obtain a thick copper circuit board.

[0080] The printed circuit board includes at least one substrate and a second copper foil adhered to both sides of the substrate, wherein the second copper foil is bonded to the substrate by a prepreg, and the thickness of the second copper foil is less than or equal to a preset threshold.

[0081] A printed circuit board may include a substrate and a second copper foil bonded to both sides of the substrate, or it may include multiple substrates bonded together, a second copper foil bonded to the outside of the top substrate, and a second copper foil bonded to the outside of the bottom substrate.

[0082] The thickness of the carrier plate is greater than a preset thickness, which is greater than a preset threshold. For example, the preset thickness is 0.2 mm, thus achieving the function of supporting the first copper foil.

[0083] Furthermore, the circuitry is fabricated on the reverse side of the first copper foil.

[0084] The method for manufacturing a thick copper circuit board provided in this application first adheres a first copper foil to a carrier board, and then creates grooves in the first copper foil. This carrier board supports and fixes the first copper foil, preventing damage or deformation during the groove fabrication process, thereby improving the yield of the thick copper circuit board. Furthermore, the adhesive between the carrier board and the first copper foil loses its adhesiveness under the high temperature and pressure of lamination, making it easy for the carrier board to separate from the first copper foil. After lamination, the adhesive is less likely to adhere to the first copper foil. Even if it does, it can be removed by grinding, plasma removal, or adhesive stripping after peeling the carrier board from the laminated printed circuit board. This avoids contamination of the first copper foil by the adhesive and ensures the performance of the thick copper circuit board.

[0085] Combination Figures 2(a) to 2(h)As shown in the figure, this embodiment provides a schematic diagram of the structural steps for fabricating a thick copper circuit board using the above method. Adhesive is applied to one side of the first copper foil 2, and the first copper foil is adhered to the carrier board 1 using the adhesive. The size of the first copper foil 2 is equal to the size of the carrier board 1, resulting in the structural schematic diagram shown in Figure 2(a). A groove 3 is formed on the side of the first copper foil 2 away from the carrier board 1, i.e., a specific area is etched to form the groove 3. The distance from the side of the first copper foil 2 that is attached to the carrier board 1 to the bottom of the groove is equal to the thickness of the second copper foil 4. This ensures that the thickness of the copper foil outside the specific area does not change, resulting in the structural schematic diagram shown in Figure 2(b). The carrier board 1 with the first copper foil 2 attached and the prepreg 5 are laminated and pressed together on any side of the printed circuit board 7, resulting in the structural schematic diagram shown in Figure 2(c). The printed circuit board 7 includes at least one substrate 6 and second copper foils 4 adhered to both sides of the substrate 6. The second copper foils 4 and the substrate 6 are bonded together by the prepreg 5. Alternatively, the carrier plate 1 with the first copper foil 2 and the prepreg 5 can be riveted and fixed to either side of the printed circuit board 7 according to a hierarchical structure, and then the carrier plate 1 with the first copper foil 2 and the prepreg 5 can be laminated and pressed onto the printed circuit board 7 to obtain the structural schematic diagram shown in Figure 2(d). Alternatively, the carrier plate 1 with the first copper foil 2 and the prepreg 5 can be laminated and pressed onto both sides of the printed circuit board 7 respectively to obtain the structural schematic diagram shown in Figure 2(e). Similarly, the carrier plate 1 with the first copper foil 2 and the prepreg 5 can be riveted and fixed onto both sides of the printed circuit board 7 according to a hierarchical structure, with the riveting and fixing connecting component 8 being, for example, a rivet, and then the carrier plate 1 with the first copper foil 2 and the prepreg 5 can be laminated and pressed onto the printed circuit board 7 to obtain the structural schematic diagram shown in Figure 2(f). Since the adhesive between the carrier board and the first copper foil loses its stickiness during the lamination process, the connecting parts can be removed after lamination to peel the carrier board off the first copper foil. If the first copper foil 2 is laminated only on one side of the printed circuit board 7, the structural schematic diagram shown in Figure 2(g) can be obtained. If the first copper foil 2 is laminated on both sides of the printed circuit board 7, the structural schematic diagram shown in Figure 2(h) can be obtained.

[0086] Combination Figures 3(a) to 3(h)As shown in the figure, this embodiment provides another schematic diagram of the structural steps for fabricating a thick copper circuit board using the above method. Adhesive is applied to one side of the first copper foil 2, and the first copper foil 2 is adhered to the carrier board 1 using the adhesive. The size of the first copper foil 2 is smaller than the size of the carrier board 1, resulting in the structural schematic diagram shown in Figure 3(a). A groove 3 is formed on the side of the first copper foil 2 away from the carrier board 1, i.e., a specific area is etched to form the groove 3. The distance from the side of the first copper foil 2 that is attached to the carrier board 1 to the bottom of the groove is equal to the thickness of the second copper foil. This ensures that the thickness of the copper foil outside the specific area does not change, resulting in the structural schematic diagram shown in Figure 3(b). The carrier board 1 with the first copper foil 2 attached and the prepreg 5 are laminated and pressed together on either side of the printed circuit board 7, resulting in the structural schematic diagram shown in Figure 3(c). Alternatively, the carrier plate 1 with the first copper foil 2 and the prepreg 5 can be riveted and fixed to either side of the printed circuit board 7 according to a hierarchical structure, wherein the connecting component 8 does not penetrate the first copper foil 2. Then, the carrier plate 1 with the first copper foil 2 and the prepreg 5 are laminated and pressed onto the printed circuit board 7, resulting in the structural schematic diagram shown in Figure 3(d). Alternatively, the carrier plate 1 with the first copper foil 2 and the prepreg 5 can be laminated and pressed onto both sides of the printed circuit board 7, resulting in the structural schematic diagram shown in Figure 3(e). Similarly, the carrier plate 1 with the first copper foil 2 and the prepreg 5 can be riveted and fixed onto both sides of the printed circuit board 7 according to a hierarchical structure, and then the carrier plate 1 with the first copper foil 2 and the prepreg 5 are laminated and pressed onto the printed circuit board 7, resulting in the structural schematic diagram shown in Figure 3(f). Since the adhesive between the carrier board and the first copper foil loses its stickiness during the lamination process, the connecting parts can be removed after lamination to peel the carrier board off the first copper foil. If the first copper foil 2 is laminated only on one side of the printed circuit board 7, the structural schematic diagram shown in Figure 3(g) can be obtained. If the first copper foil 2 is laminated on both sides of the printed circuit board 7, the structural schematic diagram shown in Figure 3(h) can be obtained. Finally, based on the structural schematic diagram shown in Figure 3(g), the area of ​​the printed circuit board 7 that does not overlap with the first copper foil 2 is removed to obtain the thick copper circuit board shown in Figure 2(g). Based on the structural schematic diagram shown in Figure 3(h), the area of ​​the printed circuit board 7 that does not overlap with the first copper foil 2 is removed to obtain the mirrored thick copper circuit board shown in Figure 2(h).

[0087] The method for manufacturing a thick copper circuit board provided in this application first adheres a first copper foil to a carrier board, and then creates grooves in the first copper foil. This carrier board supports and fixes the first copper foil, preventing damage or deformation during the groove fabrication process, thereby improving the yield of the thick copper circuit board. Furthermore, the adhesive between the carrier board and the first copper foil loses its adhesiveness under the high temperature and pressure of lamination, making it easy for the carrier board to separate from the first copper foil. After lamination, the adhesive is less likely to adhere to the first copper foil. Even if it does, it can be removed by grinding, plasma removal, or adhesive stripping after peeling the carrier board from the laminated printed circuit board. This avoids contamination of the first copper foil by the adhesive and ensures the performance of the thick copper circuit board.

[0088] In the description of the embodiments of this application, it should be understood that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, an indirect connection through an intermediate medium, the connection of internal structures of two components, or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0089] The terms "upper," "lower," "front," "rear," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. In the description of this application, "multiple" means two or more, unless otherwise precisely specified.

[0090] The terms "first," "second," "third," "fourth," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0091] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0092] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to the structural or full structural technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A method for manufacturing a thick copper circuit board, characterized in that, include: A first copper foil (2) with a thickness greater than a preset threshold is bonded to a carrier plate (1) using an adhesive substance; A groove (3) is made on the side of the first copper foil (2) away from the carrier plate (1); The side of the carrier plate (1) with the first copper foil (2) attached is pressed against the printed circuit board (7), wherein the adhesive material loses its adhesiveness during the pressing process, and the printed circuit board (7) includes multiple layers of second copper foil (4), the thickness of the second copper foil (4) being less than or equal to the preset threshold. The carrier board (1) is peeled off from the laminated printed circuit board (7) to obtain a thick copper circuit board.

2. The method according to claim 1, characterized in that, Before pressing the side of the carrier plate (1) with the first copper foil (2) attached to it against the printed circuit board (7), the method further includes: The carrier plate (1) with the first copper foil (2) bonded to it is riveted and fixed to the printed circuit board (7).

3. The method according to claim 2, characterized in that, The carrier plate (1) to which the first copper foil (2) is bonded is riveted and fixed to the printed circuit board (7), including: A first through hole is made in the area of ​​the carrier plate (1) not covered by the first copper foil (2); A second through hole is formed on the printed circuit board (7), and the second through hole is adapted to the first through hole; The carrier plate (1) to which the first copper foil (2) is bonded is riveted and fixed to the printed circuit board (7) by using the connecting component (8) through the first through hole and the second through hole.

4. The method according to claim 2, characterized in that, The carrier plate (1) to which the first copper foil (2) is bonded is riveted and fixed to the printed circuit board (7), including: At least one positioning hole is made in the area of ​​the carrier plate (1) not covered by the first copper foil (2); At least one fixing pin is made on the printed circuit board (7), and the fixing pin corresponds one-to-one with the positioning hole; Insert each of the fixing pins into the corresponding positioning holes to rivet and fix the carrier plate (1) with the first copper foil (2) bonded to it to the printed circuit board (7).

5. The method according to claim 1, characterized in that, After peeling the carrier board (1) off the laminated printed circuit board (7), the process further includes: Remove the area in the printed circuit board (7) that does not overlap with the first copper foil (2) to obtain the thick copper circuit board.

6. The method according to claim 1, characterized in that, The process of pressing the side of the carrier plate (1) with the first copper foil (2) attached to it relative to the printed circuit board (7) includes: The side of the carrier plate (1) with the first copper foil (2) attached is pressed against the printed circuit board (7) at a second preset temperature; the second preset temperature is greater than the first preset temperature.

7. The method according to claim 6, characterized in that, The viscous substance is viscous in an environment with a temperature lower than the first preset temperature, and loses its viscousness in an environment with a temperature greater than or equal to the first preset temperature.

8. The method according to claim 1, characterized in that, The method of bonding the first copper foil (2) to the carrier plate (1) using an adhesive substance includes: The front side of the first copper foil (2) is bonded to the carrier plate (1) using an adhesive material, wherein the front side of the first copper foil (2) is smoother than the back side of the first copper foil (2).

9. The method according to any one of claims 1 to 8, characterized in that, After obtaining the thick copper circuit board, the following steps are also included: Etch lines on the front side of the first copper foil (2).

10. A thick copper circuit board, characterized in that, The thick copper circuit board is obtained by the method described in any one of claims 1 to 9.

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