Printed Circuit Boards and Their Manufacturing Methods

Abstract

This invention discloses a printed circuit board and its manufacturing method. The method includes: providing a copper-clad substrate, the outer layer of which is a copper foil layer, the copper foil layer having a gold finger area and a circuit area; patterning the gold finger area of ​​the copper foil layer to obtain multiple pads, the pads being electrically connected to the copper foil layer of the circuit area; using the copper foil layer of the circuit area to connect the pads, electroplating the surface of the pads to form gold fingers; and patterning the circuit area of ​​the copper foil layer to obtain an outer layer circuit. This invention's technical solution facilitates obtaining gold fingers with a four-sided gold-plating process, eliminating the need for electroplating leads to plate the gold finger pattern, thus avoiding the impact of removing the leads on the surface flatness of the gold finger connector and the signal transmission of the printed circuit board.

Description

Technical Field

[0001] This invention relates to the field of printed circuit board technology, and more particularly to a printed circuit board and a method for manufacturing the same. Background Technology

[0002] A printed circuit board (PCB) includes gold fingers, which are electrically connected to slots or connectors to enable signal transmission.

[0003] Currently, existing printed circuit board (PCB) manufacturing methods typically involve electroplating the gold finger pattern using electroplating leads. However, this method only produces gold fingers with a three-sided gold-plating process and results in uneven surfaces on the gold finger connectors, affecting the electrical connection between the gold fingers and slots or connectors, thereby impacting signal transmission on the PCB. Summary of the Invention

[0004] This invention provides a printed circuit board and its manufacturing method to obtain gold fingers with a four-sided gold plating process. This eliminates the need to electroplate the gold finger pattern by setting electroplating leads, thereby avoiding the impact of removing the electroplating leads on the surface flatness of the gold finger connector and the signal transmission of the printed circuit board.

[0005] In a first aspect, embodiments of the present invention provide a method for manufacturing a printed circuit board, comprising:

[0006] A copper-clad substrate is provided, wherein the outer layer of the copper-clad substrate is a copper foil layer, and the copper foil layer has a gold finger area and a circuit area;

[0007] The gold finger area of ​​the copper foil layer is patterned to obtain multiple pads, which are electrically connected to the copper foil layer of the circuit area.

[0008] The copper foil layer in the circuit area is used to make each of the pads conductive, and electroplating is performed on the surface of the pads to form gold fingers;

[0009] The circuit area of ​​the copper foil layer is patterned to obtain the outer circuit.

[0010] Optionally, the process of patterning the gold finger area of ​​the copper foil layer to obtain multiple pads includes:

[0011] A first photosensitive layer is formed on the surface of the copper foil layer;

[0012] The first preset area of ​​the first photosensitive layer is exposed and developed. The gold finger area includes a gold finger pattern area corresponding to the pad. The first preset area corresponds to the gold finger pattern area and the circuit area.

[0013] Remove the first photosensitive layer outside the first preset area;

[0014] Remove the copper foil layer that is not covered by the first preset area of ​​the first photosensitive layer;

[0015] Remove the remaining first photosensitive layer to obtain a plurality of the solder pads.

[0016] Optionally, the pad includes a pad body and a pad connection portion, wherein the pad connection portion is connected between the pad body and the copper foil layer of the circuit area.

[0017] Optionally, the pad connection portion is quadrilateral, and the pad connection portion includes a first bottom edge and a second bottom edge. The length of the first bottom edge is less than or equal to the length of the second bottom edge. The first bottom edge connects to the circuit area of ​​the copper foil layer, and the second bottom edge connects to the pad body.

[0018] At least a portion of the length of the first bottom edge of the pad connection portion is greater than the line width of the outer layer circuit, and the length of the second bottom edge is equal to the width of the pad body.

[0019] Optionally, the relationship between the length of the first bottom edge of at least a portion of the pad connection and the line width of the outer layer circuit is expressed as: X1 = W + 2L;

[0020] Where X1 is the length of the first bottom edge, W is the line width of the outer layer circuit, and L is the preset length.

[0021] Optionally, the pad body includes a top surface and a first side surface, a second side surface, a third side surface, and a fourth side surface that are perpendicular to the top surface and sequentially adjacent to each other. The first side surface is opposite to the third side surface, the second side surface is opposite to the fourth side surface, and the first side surface is connected to the copper foil layer of the circuit area through the pad connection portion.

[0022] The electroplating process on the surface of the pads to form gold fingers includes:

[0023] An anti-electroplating film is formed on the surface of the copper foil layer, and the anti-electroplating film covers the circuit area of ​​the copper foil layer;

[0024] Electroplating is performed on the surface of the pad to form a nickel layer and a gold layer covering at least the top surface, the second side surface, the third side surface and the fourth side surface of the pad body, in order to obtain a gold finger;

[0025] Remove the anti-electroplation film.

[0026] Optionally, the anti-electroplating film covers at least a portion of the pad connection area, and the edge of the anti-electroplating film near the pad body is located between the copper foil layer of the circuit area and the pad body.

[0027] Optionally, the step of patterning the circuit area of ​​the copper foil layer to obtain the outer layer circuit includes:

[0028] A second photosensitive layer is formed on the surface of the copper foil layer;

[0029] The second preset area of ​​the second photosensitive layer is exposed and developed. The circuit area includes a circuit pattern area corresponding to the outer layer circuit. The second preset area corresponds to the gold finger pattern area and the circuit pattern area in the gold finger area.

[0030] Remove the second photosensitive layer outside the second preset area;

[0031] Remove the copper foil layer that is not covered by the second preset area of ​​the second photosensitive layer;

[0032] Remove the remaining second photosensitive layer to obtain the outer layer circuitry.

[0033] Optionally, the outer layer circuitry includes a first circuitry connected to the pad connection portion, wherein the first circuitry is centered and aligned with the first bottom edge of the pad connection portion.

[0034] Secondly, embodiments of the present invention provide a printed circuit board, which is manufactured using the printed circuit board manufacturing method described in the first aspect.

[0035] The printed circuit board and its manufacturing method provided in this invention first pattern the gold finger area of ​​the copper foil layer to obtain multiple pads. Each pad is electrically connected to the entire copper foil layer in the circuit area, so that the entire copper foil layer in the circuit area and all pads are in the same network, thereby enabling electroplating of each pad to form a gold finger. Then, the circuit area of ​​the copper foil layer is patterned to obtain the outer layer circuit. Compared with the prior art, the technical solution of this invention does not require electroplating by setting electroplating leads on the plug end surface of the pad. The top surface, plug end surface, left surface, and right surface of the pad can all be covered by the plating layer, thereby obtaining a four-sided gold-plated gold finger. There is no need to consider how to set the electroplating leads for different printed circuit boards. At the same time, it can also avoid the impact of removing the electroplating leads on the flatness of the gold finger plug end surface and the impact on the signal transmission of the printed circuit board, and also helps to simplify the printed circuit board manufacturing process.

[0036] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0037] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0038] Figure 1 This is a schematic diagram of a printed circuit board structure in related technologies;

[0039] Figure 2 This is a schematic flowchart of a method for manufacturing a printed circuit board according to an embodiment of the present invention;

[0040] Figures 3 to 5 This is a schematic diagram of the structure of a printed circuit board formed in the manufacturing method steps of the printed circuit board provided in the embodiment of the present invention;

[0041] Figure 6 This is a schematic flowchart of another method for manufacturing a printed circuit board provided in an embodiment of the present invention;

[0042] Figure 7 This is a schematic diagram of another printed circuit board structure formed in the manufacturing method steps of the printed circuit board provided in the embodiment of the present invention;

[0043] Figure 8 yes Figure 4 A magnified view of the first region 30 in the image;

[0044] Figure 9 This is a schematic diagram of another printed circuit board structure formed in the manufacturing method steps of the printed circuit board provided in the embodiment of the present invention;

[0045] Figure 10 This is a schematic diagram of another printed circuit board structure formed in the manufacturing method steps of the printed circuit board provided in the embodiment of the present invention. Detailed Implementation

[0046] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0047] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0048] As described in the background section, existing printed circuit board (PCB) manufacturing methods generally only produce gold fingers with a three-sided gold-plating process, which results in uneven surfaces at the gold finger connector ends. This affects the electrical connection between the gold fingers and slots or connectors, thereby impacting signal transmission on the PCB. The inventors have discovered the following reasons for this problem:

[0049] Figure 1 This is a schematic diagram of a printed circuit board structure in related technologies. See also... Figure 1In existing printed circuit board (PCB) manufacturing methods, multiple pads 02 are typically designed in the gold finger area 01 of the PCB, forming a finger-like gold finger pattern. Nickel and gold layers are then electroplated onto the surface of the pads 02 to enhance their wear resistance and conductivity, thus forming the gold finger 03. Each gold finger 03 includes a top surface 04, a connector surface 05, a tail surface 06, a left surface 07, and a right surface 08. Conventional gold finger electroplating methods typically involve designing electroplating leads 09 on the connector surface 05 of the gold finger pattern. These leads enable electrical connections between multiple gold finger patterns for electroplating. After electroplating, the leads 09 are removed, exposing the copper layer on the connector surface 05. The left, right, and top sides are then covered with nickel and gold layers, forming a three-sided gold-plating process. However, since the plug end surface 05 of the gold finger 03 has an uneven surface defect after the electroplated lead 09 is removed, and the plug end surface 05 does not have a structure of nickel layer and gold layer covering copper layer, it is easily oxidized and corroded, which further aggravates the unevenness of the plug end surface 05, affects the electrical connection between the gold finger and the slot or connector, and thus affects the signal transmission of the printed circuit board.

[0050] To address the aforementioned problems, embodiments of the present invention provide a method for manufacturing a printed circuit board, which is applicable to manufacturing printed circuit boards with gold fingers. Figure 2 This is a schematic flowchart illustrating a method for manufacturing a printed circuit board according to an embodiment of the present invention. See also... Figure 2 The method specifically includes the following steps:

[0051] S110. Provides a copper-clad substrate, the outer layer of which is a copper foil layer, and the copper foil layer has a gold finger area and a circuit area.

[0052] Figures 3 to 5 This is a schematic diagram of the structure of a printed circuit board formed in the manufacturing method steps of the printed circuit board provided in the embodiment of the present invention. Specifically, it is a top view of the printed circuit board structure, in which only the outermost copper foil layer 100 of the copper-clad substrate is shown.

[0053] Specifically, see Figure 3 The copper-clad laminate can be a copper-clad laminate that has completed the inner layer patterning, lamination, drilling, and copper plating of the holes and outer layer of the printed circuit board according to the conventional printed circuit board manufacturing process. Except for the positioning holes and the metallized holes in the unit, the entire copper-clad laminate is made of copper foil. The outermost copper foil layer 100 of the copper-clad laminate has a gold finger area 10 and a circuit area 20. The gold finger area 10 is used to form gold fingers, and the circuit area 20 is used to form the outer layer circuit.

[0054] S120. The gold finger area of ​​the copper foil layer is patterned to obtain multiple pads, each of which is electrically connected to the copper foil layer of the circuit area.

[0055] See Figure 4 The gold finger area 10 of the copper foil layer 100 is patterned to obtain multiple pads 110, each of which is electrically connected to the copper foil layer 100 of the circuit area 20. Since the circuit area 20 of the copper foil layer 100 has not yet been patterned, the copper foil layer 100 in the circuit area 20 is a single copper sheet structure, so that the copper foil layer 100 in the circuit area 20 and all the pads 110 are in the same network, and all the pads 110 can be made conductive for electroplating.

[0056] S130. The copper foil layer in the circuit area is used to make each pad conductive, and electroplating is performed on the surface of the pad to form gold fingers.

[0057] Continue to see Figure 4 In circuit region 20, the copper foil layer 100 and all pads 110 are within the same network. During electroplating, the copper foil layer 100 in circuit region 20 can be used as electroplating points to electroplat all pads 110, thereby forming a nickel layer and a gold layer sequentially on the surface of each pad 110, thus obtaining the gold finger 120. Compared with the prior art, this embodiment does not require electroplating by setting electroplating leads on the plug end surface of the pad 110, so that the top surface, plug end surface, left surface and right surface of the pad 110 can all be covered by plating, and a gold finger with a four-sided gold coating process can be obtained.

[0058] S140. Create a graphic representation of the circuit area of ​​the copper foil layer to obtain the outer circuit.

[0059] See Figure 5 The circuit area 20 of the copper foil layer 100 is patterned to obtain the outer circuit 210 that is electrically connected to the gold finger 120, thereby completing the patterning of the copper foil layer 100.

[0060] The technical solution of this invention first patterns the gold finger area of ​​the copper foil layer to obtain multiple pads. Each pad is electrically connected to the entire copper foil layer in the circuit area, so that the entire copper foil layer in the circuit area and all pads are in the same network. This allows for electroplating of each pad, forming a gold finger after electroplating. Then, the circuit area of ​​the copper foil layer is patterned to obtain the outer layer circuit. Compared with the prior art, the technical solution of this invention does not require electroplating by setting electroplating leads on the plug end surface of the pad. The top surface, plug end surface, left surface, and right surface of the pad can all be covered by the plating layer, resulting in a four-sided gold-plated gold finger. It eliminates the need to consider how to set the electroplating leads for different printed circuit boards, and also avoids the impact of removing the electroplating leads on the flatness of the gold finger plug end surface and the signal transmission of the printed circuit board. Furthermore, it helps to simplify the printed circuit board manufacturing process.

[0061] Figure 6 This is a schematic flowchart illustrating another method for manufacturing a printed circuit board according to an embodiment of the present invention. Based on the above embodiments, this embodiment further optimizes the method for manufacturing a printed circuit board. See also... Figure 6 The method specifically includes the following steps:

[0062] S202. Provide a copper-clad substrate, the outer layer of which is a copper foil layer, and the copper foil layer has a gold finger area and a circuit area.

[0063] S204. A first photosensitive layer is formed on the surface of the copper foil layer.

[0064] Figure 7 This is a schematic diagram of another printed circuit board structure formed in the manufacturing method steps of the printed circuit board provided in this embodiment of the invention. Specifically, it is a top view of the printed circuit board structure, showing only the first photosensitive layer 200. The first photosensitive layer 200 can be a dry film. Combined with... Figure 3 and Figure 7 The first photosensitive layer 200 can be attached to the entire surface of the copper foil layer 100.

[0065] S206. Expose and develop the first preset area of ​​the first photosensitive layer. The gold finger area includes the gold finger pattern area corresponding to the pad. The first preset area corresponds to the gold finger pattern area and the circuit area.

[0066] Specifically, in combination Figure 4 and Figure 7 The gold finger pattern area refers to the area where each pad 110, or gold finger 120, is located. The first preset area 40 includes the gold finger pattern area and the circuit area 20 in the gold finger area 10, that is... Figure 4The area entirely covered by the copper foil layer 100. After the first photosensitive layer 200 is attached to the entire surface of the copper foil layer 100, the first preset area 40 of the first photosensitive layer 200 is exposed to light to cure the first preset area 40 of the first photosensitive layer 200, and then the pattern is developed.

[0067] S208, Remove the first photosensitive layer outside the first preset area.

[0068] S210, Remove the copper foil layer that is not covered by the first preset area of ​​the first photosensitive layer.

[0069] S212. Remove the remaining first photosensitive layer to obtain multiple pads, each of which is electrically connected to the circuit area of ​​the copper foil layer.

[0070] For example, see Figure 7 The first photosensitive layer 200 that has not undergone photocuring, i.e., the first photosensitive layer 200 outside the first preset area 40, is removed. Then, patterned acid etching is performed to etch away the copper foil layer 100 not covered by the first preset area 40 of the first photosensitive layer 200. Next, the photocured first photosensitive layer 200 is removed, i.e., the first photosensitive layer 200 in the first preset area 40 is removed, thereby obtaining the following... Figure 4 The copper foil layer 100 shown forms multiple pads 110, and each pad 110 is electrically connected to the entire copper foil layer 100 in the circuit area 20.

[0071] Figure 8 yes Figure 4 A magnified view of the first region 30 in the image. Combined with... Figure 4 and Figure 8 Optionally, the pad 110 includes a pad body 111 and a pad connection portion 112. The pad body 111 can serve as a gold finger to be electroplated, and the pad connection portion 112 connects the pad body 111 and the copper foil layer 100 of the circuit area 20.

[0072] Optionally, the pad connection portion 112 is quadrilateral, and includes a first bottom edge 1121 and a second bottom edge 1122. The length X1 of the first bottom edge 1121 is less than or equal to the length X2 of the second bottom edge 1122. The first bottom edge 1121 connects to the circuit area 20 of the copper foil layer 100, and the second bottom edge 1122 connects to the pad body 111. At least in a portion of the pad connection portion 112, the length X1 of the first bottom edge 1121 is greater than the line width W of the outer layer circuit 210, and the length X2 of the second bottom edge 1122 is equal to the width Y of the pad body 111.

[0073] For example, the pad connection portion 112 can be trapezoidal, with a first base 1121 as the upper base and a second base 1122 as the lower base. The distance between the first base 1121 and the second base 1122, i.e., the height of the trapezoid, is H. The width Y of the pad body 111 in the extending direction of the second base 1122 is equal to the length X2 of the second base 1122. Figure 8 The dashed line in the pad connection portion 112 indicates the line width W of the outer layer circuit 210 to which it is connected. By setting the length X1 of the first bottom edge 1121 of the pad connection portion 112 to be greater than the line width W of the outer layer circuit 210, the length X1 of the first bottom edge 1121 of the pad connection portion 112 has a certain margin, so as to avoid the deviation of the graphic position during the subsequent graphic production of the outer layer circuit 210, which would affect the electrical connection between the pad connection portion 112 and the outer layer circuit 210.

[0074] Optionally, the relationship between the length X1 of the first bottom edge 1121 of at least a portion of the pad connection portion 112 and the line width W of the outer layer circuit 210 is expressed as: X1 = W + 2L. Wherein, L is a preset length, and the specific value of the preset length L can be set according to the offset range of the pattern creation. The lines in the outer layer circuit 210 connected to the pad connection portion 112 can be centered and aligned with the first bottom edge 1121 of the pad connection portion 112. For example, the outer layer circuit 210 includes a first line 211 connected to the pad connection portion 112 (see...). Figure 5 The first line 211 can be centered and aligned with the first bottom edge 1121 of the pad connection portion 112. By setting the length X1 of the first bottom edge 1121 to W+2L, the pattern offset to the left or right during the subsequent pattern making of the outer layer line 210 can be avoided, which would affect the electrical connection between the pad connection portion 112 and the outer layer line 210.

[0075] S214. An anti-electroplation film is formed on the surface of the copper foil layer, and the anti-electroplation film covers the circuit area of ​​the copper foil layer.

[0076] Among them, anti-electroplating film includes wet film or anti-electroplating tape, etc.

[0077] Figure 9 This is a schematic diagram of another printed circuit board structure formed in the manufacturing method steps of the printed circuit board provided in this embodiment of the invention, specifically a top view of the printed circuit board structure. See also... Figure 9 Before electroplating the pads 110, an anti-plating film 300 is formed on the surface of the copper foil layer 100, so that the anti-plating film 300 covers the circuit area 20 of the copper foil layer 100, which helps to avoid plating problems around the circuit area 20 of the copper foil layer 100.

[0078] Optionally, the anti-plating film 300 covers at least a portion of the pad connection portion 112, with the edge of the anti-plating film 300 near the pad body 111 located between the copper foil layer 100 of the circuit region 20 and the pad body 111. For example, the edge of the anti-plating film 300 near the pad body 111 can be positioned in the middle of the copper foil layer 100 and the pad body 111 of the circuit region 20. This ensures that the pad body 111 is covered by the plating layer while helping to prevent plating penetration in the area where the copper foil layer 100 and the pad connection portion 112 are connected in the circuit region 20.

[0079] S216. Using the copper foil layer of the circuit area to conduct each pad, electroplating is performed on the surface of the pad to form a nickel layer and a gold layer covering at least the top, second, third and fourth sides of the pad body to obtain a gold finger.

[0080] For example, combined Figure 8 and Figure 9 The pad body 111 includes a top surface 1111, a first side surface 1112, a second side surface 1113, a third side surface 1114, and a fourth side surface 1115. The first side surface 1112, the second side surface 1113, the third side surface 1114, and the fourth side surface 1115 are all perpendicular to the top surface 1111, and the first side surface 1112, the second side surface 1113, the third side surface 1114, and the fourth side surface 1115 are adjacent to each other in sequence. The first side surface 1112 is opposite to the third side surface 1114, and the second side surface 1113 is opposite to the fourth side surface 1115. The first side surface 1112 is connected to the copper foil layer 100 of the circuit area 20 through the pad connection part 112. The third side surface 1114 can be the plug end surface. After covering the areas that do not need to be electroplated with the anti-electroplation film 300, the copper foil layer 100 in the circuit area 20 can be used as an electroplating pinch point to electroplat the copper foil layer 100 that is not covered by the anti-electroplation film 300, so as to form a nickel layer and a gold layer on the surface of the pad body 111 in sequence, such that the nickel layer and the gold layer at least cover the top surface 1111, the second side surface 1113, the third side surface 1114 and the fourth side surface 1115 of the pad body 111, so as to obtain the gold fingers 120 with a four-sided gold-coating process.

[0081] S218, Remove the anti-electroplation film.

[0082] S220, A second photosensitive layer is formed on the surface of the copper foil layer.

[0083] Figure 10 This is a schematic diagram of another printed circuit board structure formed in the manufacturing method steps of the printed circuit board provided in this embodiment of the invention. Specifically, it is a top view of the printed circuit board structure, showing only the second photosensitive layer 400. The second photosensitive layer 400 can be a dry film. Combined with... Figure 9 and Figure 10After electroplating is completed, the anti-electroplation film 300 is removed, and a second photosensitive layer 400 is attached to the entire surface of the copper foil layer 100.

[0084] S222. Expose and develop the second preset area of ​​the second photosensitive layer. The circuit area includes the circuit pattern area corresponding to the outer circuit. The second preset area corresponds to the gold finger pattern area and the circuit pattern area in the gold finger area.

[0085] Combination Figure 5 , Figure 9 and Figure 10 The circuit graphic area is the area where the outer circuit 210 is located. The second preset area 50 includes the gold finger graphic area and the circuit graphic area, that is... Figure 5 The area entirely covered by the copper foil layer 100. After the second photosensitive layer 400 is attached to the entire surface of the copper foil layer 100, the second preset area 50 of the second photosensitive layer 400 is exposed to light, thereby photocuring the second preset area 50 of the second photosensitive layer 400, followed by pattern development. The pattern exposure in steps S206 and S222 can use the same positioning system to reduce positional deviation between the two patterns.

[0086] S224. Remove the second photosensitive layer outside the second preset area.

[0087] S226. Remove the copper foil layer that is not covered by the second preset area of ​​the second photosensitive layer.

[0088] S228. Remove the remaining second photosensitive layer to obtain the outer layer circuitry.

[0089] For example, see Figure 10 The uncured second photosensitive layer 400, i.e., the second photosensitive layer 400 outside the second preset region 50, is removed. Then, patterned acid etching is performed to etch away the copper foil layer 100 not covered by the second preset region 50 of the second photosensitive layer 400. Next, the photocured second photosensitive layer 400 is removed, i.e., the second photosensitive layer 400 in the second preset region 50 is removed, thus obtaining the following... Figure 5 The copper foil layer shown forms an outer layer circuit 210 that is electrically connected to the pad 110.

[0090] The technical solution of this invention forms the gold finger 120 and the outer layer circuit 210 through two pattern transfer processes, and a pad connection portion 112 is made in the junction area of ​​the gold finger 120 and the outer layer circuit 210, which helps to achieve good splicing of the two patterns. Compared with the prior art, the technical solution of this invention does not require electroplating by setting electroplating leads on the plug end surface of the pad 110, so that the top surface 1111, the second side surface 1113, the third side surface 1114 and the fourth side surface 1115 of the pad body 111 can all be covered by the plating layer, thereby obtaining a gold finger with a four-sided gold coating process. There is no need to consider how to set the electroplating leads for different printed circuit boards. At the same time, it can also avoid the impact of removing the electroplating leads on the flatness of the gold finger plug end surface and the impact on the signal transmission of the printed circuit board, and also helps to simplify the printed circuit board manufacturing process.

[0091] This invention also provides a printed circuit board, which can be manufactured using the printed circuit board manufacturing method in any of the above embodiments, and thus has the corresponding beneficial effects of the printed circuit board manufacturing method, which will not be elaborated here.

[0092] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0093] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A method for manufacturing a printed circuit board, characterized in that, include: A copper-clad substrate is provided, wherein the outer layer of the copper-clad substrate is a copper foil layer, and the copper foil layer has a gold finger area and a circuit area; The gold finger area of ​​the copper foil layer is patterned to obtain multiple pads, which are electrically connected to the copper foil layer of the circuit area. The copper foil layer in the circuit area is used to make each of the pads conductive, and electroplating is performed on the surface of the pads to form gold fingers; The circuit area of ​​the copper foil layer is patterned to obtain the outer circuit. The pad includes a pad body and a pad connection portion, wherein the pad connection portion connects the pad body and the copper foil layer of the circuit area; The pad connection portion is quadrilateral, and the pad connection portion includes a first bottom edge and a second bottom edge. The first bottom edge connects to the circuit area of ​​the copper foil layer, and the second bottom edge connects to the pad body. At least a portion of the length of the first bottom edge of the pad connection portion is greater than the line width of the outer layer circuit, and the length of the second bottom edge is equal to the width of the pad body. The lines connected to the pads in the outer layer are aligned with the first bottom edge of the pad connection to prevent left or right offset during subsequent pattern creation of the outer layer, which would affect the electrical connection between the pad connection and the outer layer.

2. The method for manufacturing a printed circuit board according to claim 1, characterized in that, The process of patterning the gold finger area of ​​the copper foil layer to obtain multiple pads includes: A first photosensitive layer is formed on the surface of the copper foil layer; The first preset area of ​​the first photosensitive layer is exposed and developed. The gold finger area includes a gold finger pattern area corresponding to the pad. The first preset area corresponds to the gold finger pattern area and the circuit area. Remove the first photosensitive layer outside the first preset area; Remove the copper foil layer that is not covered by the first preset area of ​​the first photosensitive layer; Remove the remaining first photosensitive layer to obtain a plurality of the solder pads.

3. The method for manufacturing a printed circuit board according to claim 1, characterized in that, The length of the first base is less than or equal to the length of the second base.

4. The method for manufacturing a printed circuit board according to claim 3, characterized in that, The relationship between the length of the first bottom edge of at least a portion of the pad connection portion and the line width of the outer layer circuit is expressed as: X1 = W + 2L; Where X1 is the length of the first bottom edge, W is the line width of the outer layer circuit, and L is the preset length.

5. The method for manufacturing a printed circuit board according to claim 1, characterized in that, The pad body includes a top surface, and a first side surface, a second side surface, a third side surface, and a fourth side surface that are perpendicular to the top surface and sequentially adjacent to each other. The first side surface is opposite to the third side surface, and the second side surface is opposite to the fourth side surface. The first side surface is connected to the copper foil layer of the circuit area through the pad connection portion. The electroplating process on the surface of the pads to form gold fingers includes: An anti-electroplating film is formed on the surface of the copper foil layer, and the anti-electroplating film covers the circuit area of ​​the copper foil layer; Electroplating is performed on the surface of the pad to form a nickel layer and a gold layer covering at least the top surface, the second side surface, the third side surface and the fourth side surface of the pad body, in order to obtain a gold finger; Remove the anti-electroplation film.

6. The method for manufacturing a printed circuit board according to claim 5, characterized in that, The anti-electroplation film covers at least a portion of the pad connection area, and the edge of the anti-electroplation film near the pad body is located between the copper foil layer and the pad body in the circuit area.

7. The method for manufacturing a printed circuit board according to claim 3, characterized in that, The process of creating a pattern for the circuit area of ​​the copper foil layer to obtain the outer circuit includes: A second photosensitive layer is formed on the surface of the copper foil layer; The second preset area of ​​the second photosensitive layer is exposed and developed. The circuit area includes a circuit pattern area corresponding to the outer layer circuit. The second preset area corresponds to the gold finger pattern area and the circuit pattern area in the gold finger area. Remove the second photosensitive layer outside the second preset area; Remove the copper foil layer that is not covered by the second preset area of ​​the second photosensitive layer; Remove the remaining second photosensitive layer to obtain the outer layer circuitry.

8. The method for manufacturing a printed circuit board according to claim 7, characterized in that, The outer layer circuitry includes a first circuitry connected to the pad connection portion, wherein the first circuitry is centered and aligned with the first bottom edge of the pad connection portion.

9. A printed circuit board, characterized in that, The printed circuit board is manufactured using the printed circuit board manufacturing method described in any one of claims 1-8.

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