Circuit board manufacturing method, circuit board and battery

Abstract

The invention provides a circuit board manufacturing method, a circuit board and a battery, and relates to the technical field of circuit board preparation. The circuit board manufacturing method comprises the following steps: providing a substrate with a circuit pattern layer; forming a thickened bonding pad in a preset area of the circuit pattern layer; the thickened bonding pad is electrically connected with the circuit pattern layer; the thickened bonding pad is used for mounting an electronic device; forming a solder mask layer on the circuit pattern layer; the surface, away from the substrate, of the solder mask layer is lower than or flush with the surface, away from the substrate, of the thickened bonding pad. Through the arrangement, the installation foundation of the electronic device can be raised, the distance between the electronic device and the substrate is increased, and the heat dissipation performance and the filling fluidity of the bottom filling glue can be improved.

Description

Technical Field

[0001] This invention relates to the field of circuit board manufacturing technology, and in particular to a method for manufacturing a circuit board, a circuit board, and a battery. Background Technology

[0002] In the manufacturing process of printed circuit boards (PCBs), as the requirements for heat dissipation performance and packaging reliability of electronic devices continue to increase, current PCB structures are insufficient to meet the assembly needs of high-power devices or devices requiring underfill. In traditional PCB designs, the contact area between the bottom of the device and the PCB surface is small, and the vertical space for heat dissipation and underfill is narrow, hindering heat dissipation. Furthermore, when filling the underfill, issues such as obstructed capillary flow, difficulty in adhesive injection, slow and uneven adhesive flow, and the formation of bubbles and voids after curing can easily occur, thus affecting the long-term reliability of the device. Summary of the Invention

[0003] The purpose of this invention is to provide a circuit board manufacturing method, a circuit board, and a battery, which are beneficial for improving heat dissipation performance and increasing the reliability of the bottom filler.

[0004] In a first aspect, the present invention provides a method for manufacturing a circuit board, comprising: Provide a substrate with a circuit pattern layer; Thick pads are formed in a predetermined area of ​​the circuit pattern layer; the thickened pads are electrically connected to the circuit pattern layer; the thickened pads are used for mounting electronic components; A solder mask layer is formed on the circuit pattern layer; the surface of the solder mask layer away from the substrate is lower than or flush with the surface of the thickened pads away from the substrate.

[0005] In an optional implementation, the step of forming thickened pads in a predetermined area of ​​the circuit pattern layer includes: A removable medium is attached to the circuit pattern layer; A groove is formed on the removable medium to expose the preset area; The thickened pad is formed by filling the groove with a conductive medium. Remove the removable medium.

[0006] In an optional embodiment, the step of attaching a removable medium onto the circuit pattern layer includes attaching a photosensitive dry film onto the circuit pattern layer.

[0007] In an optional implementation, the step of forming a groove on the removable medium that exposes the preset area includes: A groove is formed on the removable medium to expose the preset area using an exposure and development method; wherein, the exposure method includes contact exposure of the removable medium using an ultraviolet light source, or non-contact exposure of the removable medium using laser imaging.

[0008] In an optional embodiment, the step of attaching a removable medium onto the circuit pattern layer includes: attaching a photosensitive dry film onto the circuit pattern layer. The step of forming a groove exposing the preset area on the removable medium by exposure and development includes: A black and white film negative is attached to the photosensitive dry film; The substrate, to which the photosensitive dry film and the film are bonded, is placed in an ultraviolet light exposure machine for ultraviolet light irradiation; The groove is formed by dissolving the photosensitive dry film that has not been exposed to ultraviolet light using a developing solution.

[0009] In an optional embodiment, the step of filling the groove with a conductive dielectric to form the thickened pad includes: The thickened pad is formed by filling the groove with metal material using an electroplating method.

[0010] In an optional implementation, the step of providing a substrate having a circuit pattern layer includes: The circuit pattern layer is formed on the surface of the substrate; In the step of forming a solder resist layer on the circuit pattern layer, the solder resist layer avoids the mounting area of ​​the electronic device.

[0011] In a second aspect, the present invention provides a circuit board manufactured using the circuit board manufacturing method described in any of the foregoing embodiments, the circuit board comprising: A substrate with a circuit pattern layer; Thickened pads are provided on the side of the circuit pattern layer away from the substrate, and the thickened pads are electrically connected to the circuit pattern layer. A solder resist layer covering the circuit pattern layer; the surface of the solder resist layer away from the substrate is lower than or flush with the surface of the thickened pads away from the substrate.

[0012] In an optional embodiment, the thickened pads and the solder resist layer are respectively provided on both sides of the substrate.

[0013] In an optional embodiment, the height of the thickened pad protruding from the surface of the circuit pattern layer is 20 micrometers to 40 micrometers.

[0014] Thirdly, the present invention provides a battery comprising a circuit board as described in the foregoing embodiments.

[0015] The circuit board manufacturing method, circuit board, and battery provided in this invention have the following beneficial effects: Thickened pads are formed in the preset area of ​​the circuit pattern layer, achieving a "lifting" effect on the pads. This increases the heat dissipation space and filler space in the vertical direction, thereby improving the heat dissipation conditions after electronic components are mounted and the flowability of the underfill adhesive. During underfilling, capillary action is enhanced, the adhesive flow rate is increased, and phenomena such as bubbles and voids appearing after adhesive filling are reduced, thus improving the long-term reliability of electronic components.

[0016] The circuit board provided in this embodiment of the invention is prepared by the above-described circuit board manufacturing method, which is beneficial to improving the heat dissipation conditions and the flowability of the bottom filler after electronic components are mounted, thereby improving the reliability of the packaging.

[0017] The battery provided in this embodiment of the invention uses the above-mentioned circuit board, which has good heat dissipation performance, good reliability, and improves the performance of the battery product. Attached Figure Description

[0018] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of a first structure of a circuit board provided in an embodiment of the present invention; Figure 2 One of the process diagrams of a circuit board provided in an embodiment of the present invention; Figure 3 A second schematic diagram of the manufacturing process of a circuit board provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of a second structure of a circuit board provided in an embodiment of the present invention; Figure 5 This is a schematic diagram of the structure of a circuit board after electronic devices have been mounted, provided in an embodiment of the present invention. Figure 6 This is a schematic diagram of a third structure of a circuit board provided in an embodiment of the present invention.

[0020] Icons: 110 - Substrate; 120 - Circuit pattern layer; 121 - First pad; 130 - Thick pad; 140 - Solder mask; 150 - Removable dielectric; 151 - Groove; 200 - Electronic component; 210 - Connecting pad; 220 - Solder paste; 230 - Underfill adhesive. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0022] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0023] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0024] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use. They are only for the convenience of describing this invention 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, and therefore should not be construed as a limitation of this invention. In addition, the terms "first," "second," "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0025] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0026] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0027] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0028] This invention discloses a circuit board manufacturing method for preparing circuit boards. The circuit board can be used to mount electronic components, thereby improving the heat dissipation performance of the electronic components and enhancing the reliability of component mounting. This circuit board is applicable to any electronic product field.

[0029] Please combine Figures 1 to 3 , Figure 5 This embodiment proposes a circuit board manufacturing method, including providing a substrate 110 with a circuit pattern layer 120; forming a thickened pad 130 in a predetermined area of ​​the circuit pattern layer 120; electrically connecting the thickened pad 130 and the circuit pattern layer 120; using the thickened pad 130 for mounting electronic devices 200; forming a solder resist layer 140 on the circuit pattern layer 120; the surface of the solder resist layer 140 away from the substrate 110 is lower than or flush with the surface of the thickened pad 130 away from the substrate 110. This circuit board manufacturing method aims to achieve a "lifting" effect on the pads by forming a locally thickened pad structure in a specific area, thereby improving the heat dissipation conditions after mounting the electronic devices 200 and the flowability of the underfill adhesive 230.

[0030] Specifically, taking the single-sided fabrication process of substrate 110 as an example, this circuit board manufacturing method first provides a substrate 110 with a circuit pattern layer 120. The circuit pattern layer 120 has undergone pattern transfer and metallization processing through conventional front-end processes and has complete circuit connection functions. In this embodiment, forming the circuit pattern layer 120 on the surface of substrate 110 is beneficial to improving heat dissipation performance, and the fabrication process is simpler and more convenient.

[0031] Subsequently, a thickened pad 130 is formed in a predetermined area of ​​the circuit pattern layer 120. This thickened pad 130 maintains an electrical connection with the original circuit pattern layer 120 to ensure the integrity of the electrical path. Simultaneously, this thickened pad 130 is configured for subsequent mounting of electronic devices 200. The electronic devices 200 include, but are not limited to, power MOSFETs (power metal-oxide-semiconductor field-effect transistors), control chips, and other components with high requirements for heat dissipation or packaging quality.

[0032] In this embodiment, a taller pad structure is constructed on the original circuit pattern layer 120 using additive manufacturing, making it protrude vertically from the ordinary circuit area. Optionally, after the thickened pad 130 is formed, a solder mask layer 140 is formed on the circuit pattern layer 120. The function of the solder mask layer 140 is to cover the non-soldered areas to prevent short circuits and oxidation. The surface of the solder mask layer 140 away from the substrate 110 is lower than or flush with the surface of the thickened pad 130 away from the substrate 110. This means that the solder mask layer 140 does not cover the top of the thickened pad 130, thereby ensuring that the thickened pad 130 can still be exposed for soldering and providing sufficient vertical space for mounting electronic devices 200.

[0033] It is understandable that the circuit pattern layer 120 mostly uses copper. The thickened solder pads 130 also use copper. Of course, other metal materials can also be used, and this is not specifically limited. This embodiment achieves the characteristic of different copper thicknesses within the same layer structure by locally thickening the copper layer on the basis of the existing circuit pattern layer 120 and cooperating with the non-coverage design of the solder mask layer 140. In other words, this embodiment improves the functionality of the key solder joint area without increasing the overall board thickness by constructing a "boss-type" solder pad structure. It can be seen that this structure can not only increase the volume of the three-dimensional heat dissipation channel between the electronic device 200 and the substrate 110 and improve the heat conduction efficiency, but also expand the flow space of the bottom filler adhesive 230, reduce capillary flow resistance, promote uniform filling of adhesive, reduce the occurrence of void defects, and improve the reliability of the mounted electronic device 200.

[0034] As an example, when this circuit board is applied to a battery protection board, after the key power devices are soldered onto the thickened pads 130, the bottom gap is increased, which facilitates the rapid penetration of the bottom filler 230 from the edge to the center area, improving packaging consistency and reliability, and also improving heat dissipation performance.

[0035] In this embodiment, the steps for forming the thickened pad 130 in the preset area of ​​the circuit pattern layer 120 are roughly as follows: The surfaces of the substrate 110 and the circuit pattern layer 120 are cleaned. A removable dielectric 150 is then attached to the circuit pattern layer 120. The removable dielectric 150 can be a dry film or photoresist, etc. Taking a photosensitive dry film as an example, the removable dielectric 150 is attached to the circuit pattern layer 120. A photosensitive dry film with a thickness of 30µm to 50µm can be covered by wet lamination or vacuum lamination.

[0036] A groove 151 exposing a predetermined area is formed on the removable medium 150. The groove 151 is formed on the removable medium 150 using an exposure and development method. The predetermined area is the pad area where the electronic device 200 needs to be mounted. The exposure method includes contact exposure of the removable medium 150 using an ultraviolet light source, or non-contact exposure of the removable medium 150 using laser imaging. In this embodiment, the groove 151 is formed on a photosensitive dry film through exposure and development. Specifically, a black and white film is attached to the photosensitive dry film. It can be understood that the film has black and white areas. The black areas are opaque, while the white areas are translucent. The substrate 110, with the photosensitive dry film and film attached, is placed in an ultraviolet light exposure machine for ultraviolet irradiation. When ultraviolet light irradiates the film, it can pass through the white areas and irradiate the dry film covering the white areas, causing the dry film covering the white areas to undergo a curing reaction. The black areas on the film block ultraviolet light from passing through, and the dry film covered by these black areas does not undergo a curing reaction. Alternatively, non-contact exposure of the photosensitive dry film can be performed using Laser Direct Imaging (LDI). The photosensitive dry film not exposed to ultraviolet light is dissolved using a developing solution, forming grooves 151. The developing solution selectively dissolves the dry film that has not undergone a curing reaction; that is, the dry film covered by the black areas of the film is dissolved and removed. At this point, grooves 151 expose a predetermined area on the circuit pattern layer 120.

[0037] A thickened pad 130 is formed by filling the groove 151 with a conductive dielectric. Alternatively, the thickened pad 130 can be formed by filling the groove 151 with a metal material using electroplating. In this embodiment, a copper pillar, i.e., the thickened pad 130, is formed within the groove 151 using pulse electroplating. The height of the thickened pad 130 is approximately 20µm to 40µm, meaning the height of the thickened pad 130 protruding from the circuit pattern layer 120 is approximately 20µm to 40µm. The height of the thickened pad 130 can be flexibly designed according to actual mounting requirements and is not specifically limited here. In other embodiments, the thickened pad 130 can also be formed using methods such as electroless plating, sputtering, or vapor deposition.

[0038] Remove the removable medium 150. Optionally, remove all photosensitive dry film using a stripping process. At this point, thickened pads 130 with boss structures have been formed on the circuit pattern layer 120.

[0039] Finally, the solder mask layer 140 is prepared. It is understood that the circuit pattern layer 120 is located on the surface of the substrate 110. The substrate 110 can be made of ceramic, glass, silicon, or resin, etc. Forming the solder mask layer 140 on the circuit pattern layer 120 can both protect the circuit pattern layer 120 and provide electrical isolation.

[0040] Optionally, the solder mask 140 avoids the mounting area of ​​the electronic component 200. This arrangement provides greater flow space for the underfill adhesive 230 in the mounting area. For example, if the mounting area is designed with six thickened pads 130 for mounting the electronic component 200, then the solder mask 140 is not provided between these six thickened pads 130, nor within the area enclosed by the six thickened pads 130. The solder mask 140 covers the circuit pattern layer 120 outside the mounting area. This provides greater filling space both horizontally and vertically when applying the underfill adhesive 230, expanding the flow space of the underfill adhesive 230, promoting rapid penetration of the adhesive from the edges to the center area, reducing capillary flow resistance, promoting uniform adhesive filling, and reducing the occurrence of voids.

[0041] It is understandable that, based on the actual situation, the outer perimeter of the six thickened solder pads 130 may not require a solder mask layer 140, which will be used for subsequent filling with underfill adhesive 230. Figure 1 As shown. Alternatively, a solder mask layer 140 can be partially designed within the area enclosed by the six thickened solder pads 130, with the remainder used for subsequent filling with underfill adhesive 230, as shown. Figure 4 As shown, no specific limitations are made here.

[0042] Please continue to combine Figure 1 This invention also provides a circuit board manufactured using any of the circuit board manufacturing methods described in the foregoing embodiments. The circuit board includes a substrate 110 with a circuit pattern layer 120, thickened pads 130, and a solder mask layer 140. The thickened pads 130 are located on the side of the circuit pattern layer 120 away from the substrate 110, and are electrically connected to the circuit pattern layer 120. The solder mask layer 140 covers the circuit pattern layer 120; the surface of the solder mask layer 140 away from the substrate 110 is lower than or flush with the surface of the thickened pads 130 away from the substrate 110. In the mounting area of ​​the electronic device 200, the circuit board incorporates thickened pads 130. After the electronic device 200 is mounted onto the thickened pads 130, the distance between the bottom of the electronic device 200 and the surface of the substrate 110 is increased, increasing the heat dissipation space and the filling space of the bottom filler adhesive 230, which is beneficial for improving heat dissipation performance and mounting reliability.

[0043] Optionally, the surface of the solder mask 140 away from the substrate 110 is lower than the surface of the thickened pad 130 away from the substrate 110. This further increases the space for colloid flow and heat dissipation.

[0044] The solder mask layer 140 avoids the mounting area, providing more space for the bottom filler adhesive 230. This helps improve the fluidity of the adhesive, reduce flow resistance, improve filling uniformity, reduce the occurrence of bubbles and voids, and improve the reliability of the electronic components 200 mounting.

[0045] It is understandable that the structure after mounting 200 electronic components is as follows: Figure 5 As shown, the connecting pads 210 of the electronic device 200 and the thickened pads 130 on the circuit board are soldered with solder paste 220 to achieve electrical connection. When the bottom of the electronic device 200 is filled with underfill adhesive 230, the underfill adhesive 230 will penetrate into the spaces between the thickened pads 130 and extend vertically to the surface of the substrate 110, filling the gaps between the circuit pattern layers 120, and playing a role in electrical isolation, bonding and fixing, and heat conduction.

[0046] It should be noted that in this circuit board structure, the thickened pads 130 can be designed only for the component mounting areas that require bottom filling, while the remaining mounting areas can use either the first pad 121 of normal thickness or the thickened pads 130. If multiple mounting areas are designed with thickened pads 130, the heights of the thickened pads 130 in different mounting areas can be equal or unequal, and no specific limitation is made here. Figure 6 A schematic diagram of a structure is shown, showing that all pads on substrate 110 are designed as thickened pads 130.

[0047] Optionally, the height of the thickened pad 130, i.e., the height of the thickened pad 130 protruding from the circuit pattern layer 120, is approximately 20µm to 40µm, such as 20µm, 22µm, 25µm, 28µm, 30µm, 32µm, 35µm, 38µm, 40µm, or any other value between 20µm and 40µm. This setting increases the distance between the surface of the thickened pad 130 and the surface of the circuit pattern layer 120, increasing the filling space of the bottom filler adhesive 230, which is beneficial for adhesive flow, promotes uniform adhesive filling, reduces the occurrence of voids, improves mounting reliability, and also helps improve heat dissipation performance.

[0048] The substrate 110 can employ double-sided wiring, enabling double-sided mounting and improving integration. If double-sided mounting is used, the design method for the thickened pads 130 on both sides is similar and will not be repeated here. In other words, the substrate 110 has thickened pads 130 and solder mask layers 140 on both sides, which helps to improve the surface utilization of the substrate 110 and increase the integration of the mounted electronic devices 200.

[0049] This invention also provides a battery, including a circuit board as described in the preceding embodiments. This circuit board can serve as a protective board for the battery. After the electronic components 200 are soldered onto the thickened pads 130, the increased bottom gap facilitates the rapid penetration of the bottom filler adhesive 230 from the edges to the center area, improving packaging consistency and reliability, and also enhancing heat dissipation performance.

[0050] In summary, the circuit board manufacturing method, circuit board, and battery provided by the embodiments of the present invention have the following beneficial effects, including: Thickened pads 130 are formed in a preset area of ​​the circuit pattern layer 120, achieving a "lifting" effect on the pads. This increases the vertical heat dissipation space and adhesive filling space, thereby improving the heat dissipation conditions of the electronic device 200 after mounting and the flowability of the underfill adhesive 230. During underfill adhesive 230 filling, capillary action is enhanced, increasing the adhesive flow rate and reducing phenomena such as bubbles and voids after adhesive filling, thus improving the long-term reliability and heat dissipation of the electronic device 200. This circuit board manufacturing method, without changing the mainstream SMT (Surface Mount Technology) process flow, effectively solves the technical bottlenecks of poor heat dissipation and difficult adhesive filling in existing technologies by introducing a controllable localized thickened pad 130 process.

[0051] The circuit board provided in this embodiment of the invention is prepared by the above-described circuit board manufacturing method, which is beneficial to improving the heat dissipation conditions after the electronic device 200 is mounted and the flowability of the bottom filler adhesive 230, thereby improving the packaging reliability.

[0052] The battery provided in this embodiment of the invention uses the above-mentioned circuit board, which has good heat dissipation performance, good reliability, and improves the performance of the battery product.

[0053] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention 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 some or all of the technical features; any modifications, equivalent substitutions, improvements, etc., should be included within the protection scope of the present invention.

Claims

1. A method for manufacturing a circuit board, characterized in that, include: A substrate (110) having a circuit pattern layer (120) is provided; Thick pads (130) are formed in a predetermined area of ​​the circuit pattern layer (120); the thick pads (130) and the circuit pattern layer (120) are electrically connected; the thick pads (130) are used to mount electronic devices (200). A solder mask layer (140) is formed on the circuit pattern layer (120); the surface of the solder mask layer (140) away from the substrate (110) is lower than or flush with the surface of the thickened pad (130) away from the substrate (110).

2. The circuit board manufacturing method according to claim 1, characterized in that, The step of forming a thickened pad (130) in a predetermined area of ​​the circuit pattern layer (120) includes: A removable medium (150) is attached to the circuit pattern layer (120); A groove (151) is formed on the removable medium (150) to expose the preset area. The thickened pad (130) is formed by filling the groove (151) with a conductive medium. Remove the removable medium (150).

3. The circuit board manufacturing method according to claim 2, characterized in that, The step of attaching a removable medium (150) on the circuit pattern layer (120) includes attaching a photosensitive dry film on the circuit pattern layer (120).

4. The circuit board manufacturing method according to claim 2, characterized in that, The step of forming a groove (151) exposing the preset area on the removable medium (150) includes: A groove (151) exposing the preset area is formed on the removable medium (150) by means of exposure and development; wherein, the exposure method includes contact exposure of the removable medium (150) using an ultraviolet light source, or non-contact exposure of the removable medium (150) using laser imaging.

5. The circuit board manufacturing method according to claim 4, characterized in that, The step of attaching a removable medium (150) onto the circuit pattern layer (120) includes attaching a photosensitive dry film onto the circuit pattern layer (120); The step of forming a groove (151) exposing the preset area on the removable medium (150) by means of exposure and development includes: A black and white film negative is attached to the photosensitive dry film; The substrate (110) with the photosensitive dry film and the film attached is placed in an ultraviolet light exposure machine for ultraviolet light irradiation; The groove (151) is formed by dissolving the photosensitive dry film that has not been exposed to ultraviolet light using a developing solution.

6. The circuit board manufacturing method according to claim 2, characterized in that, The step of filling the groove (151) with a conductive dielectric to form the thickened pad (130) includes: The thickened pad (130) is formed by filling the groove (151) with metal material using an electroplating method.

7. The circuit board manufacturing method according to claim 1, characterized in that, The steps of providing a substrate (110) having a circuit pattern layer (120) include: The circuit pattern layer (120) is formed on the surface of the substrate (110). In the step of forming a solder mask layer (140) on the circuit pattern layer (120), the solder mask layer (140) avoids the mounting area of ​​the electronic device (200).

8. A circuit board, characterized in that, The circuit board is manufactured using the circuit board manufacturing method according to any one of claims 1 to 7, wherein the circuit board comprises: A substrate (110) having a circuit pattern layer (120); Thick pad (130) is provided on the side of the circuit pattern layer (120) away from the substrate (110), and the thick pad (130) and the circuit pattern layer (120) are electrically connected. A solder mask layer (140) covers the circuit pattern layer (120); the surface of the solder mask layer (140) away from the substrate (110) is lower than or flush with the surface of the thickened pad (130) away from the substrate (110).

9. The circuit board according to claim 8, characterized in that, The substrate (110) has the thickened pad (130) and the solder resist layer (140) on both sides respectively.

10. The circuit board according to claim 8, characterized in that, The height of the thickened pad (130) protruding from the surface of the circuit pattern layer (120) is 20 micrometers to 40 micrometers.

11. A battery, characterized in that, The circuit board includes any one of claims 8 to 10.

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