Method of manufacturing a circuit board assembly and circuit board assembly

Abstract

A method for manufacturing a circuit board assembly includes the steps of: disposing a conductive paste between a first connecting region of a first circuit board and a second connecting region of a second circuit board and laminating the first connecting region and the second connecting region to electrically connect the first circuit board and the second circuit board; forming a receiving groove in the first connecting region and the second connecting region, the receiving groove extending through the first connecting region and to at least a portion of the second connecting region; and filling the receiving groove with an insulating material to form a fixing post. The application also includes a circuit board assembly.

Description

Technical Field

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

[0002] Existing circuit boards are typically interconnected using connectors, but these connectors are relatively large. Therefore, solder paste is used to achieve electrical connection between two interconnecting circuit boards, and adhesive is used to bond them together to increase the reliability of the connection. However, during the manufacturing process, the adhesive and solder paste are placed between the two circuit boards, and then a reflow process is performed to melt and solidify the solder paste. This process can reduce the adhesive properties of the adhesive. If high-temperature resistant thermosetting adhesives or hot melt adhesives are used, a high-temperature and high-pressure process is required. Applying pressure in a limited connection area can easily lead to solder joint abnormalities, such as insufficient solder or misalignment. Summary of the Invention

[0003] A method for manufacturing a circuit board assembly includes the following steps: applying conductive paste between a first connection area of ​​a first circuit board and a second connection area of ​​a second circuit board, and stacking the first connection area and the second connection area to electrically connect the first circuit board and the second circuit board; forming a receiving groove in the first connection area and the second connection area, the receiving groove penetrating the first connection area and extending to at least a portion of the second connection area; and filling the receiving groove with insulating material to form a fixing post.

[0004] In some embodiments of this application, before the step of stacking the first connection area and the second connection area, the manufacturing method further includes: forming a through hole through the first connection area on the first circuit board;

[0005] After the step of stacking the first connection area and the second connection area, a portion of the second connection area is exposed to the through hole; in the step of forming the receiving groove, the receiving groove is formed in the area where the through hole is located.

[0006] In some embodiments of this application, a filler is provided on the second connection area exposed to the through hole, and the color of the filler is different from the color of the surface of the first connection area.

[0007] In some embodiments of this application, along a direction perpendicular to the stacked arrangement of the first and second circuit boards, the diameter of the positioning groove is larger than the diameter of the through hole, and the filler is also accommodated in the through hole.

[0008] In some embodiments of this application, the filler material is the same as the conductive paste material.

[0009] In some embodiments of this application, prior to the step of stacking the first connection area and the second connection area, the first circuit board includes a first circuit layer, the first connection area is provided with a first opening, and the first circuit layer is exposed to the first opening; the second circuit board includes a second circuit layer, the second connection area is provided with a second opening, and the second circuit layer is exposed to the second opening.

[0010] The conductive paste is placed in the first opening and / or the second opening and then melted and cured.

[0011] A circuit board assembly includes a first circuit board, a second circuit board, conductive paste, and a fixing post. The first circuit board includes a first connection area; the second circuit board includes a second connection area, and the first connection area and the second connection area are stacked. The conductive paste is disposed between the first connection area and the second connection area to electrically connect the first circuit board and the second circuit board. The fixing post passes through the first connection area and is disposed at least in the second connection area to fix the first circuit board and the second circuit board.

[0012] In some embodiments of this application, the fixing post passes through both the first connection area and the second connection area.

[0013] In some embodiments of this application, the circuit board assembly further includes a filler located between the first connection area and the second connection area and surrounding the fixing post.

[0014] In some embodiments of this application, the filler material is the same as the conductive paste material.

[0015] The method for manufacturing the circuit board assembly in this application involves first applying conductive paste for electrical connection between the first circuit board and the second circuit board, and then forming a fixing post for fixing. That is, the process involves a high temperature and high pressure step, so it does not affect the fixing effect of the subsequently formed fixing post, and does not reduce the connection performance of the fixing post. Attached Figure Description

[0016] Figure 1 This is a cross-sectional schematic diagram of the first circuit board according to an embodiment of this application.

[0017] Figure 2 In order to be in Figure 1 The diagram shows a cross-section of the circuit board after through-holes have been formed.

[0018] Figure 3 This is a cross-sectional schematic diagram of the second circuit board according to an embodiment of this application.

[0019] Figure 4 In order to be in Figure 2 The first circuit board shown and Figure 3 The diagram shows a cross-sectional view of conductive paste applied between the second circuit boards.

[0020] Figure 5 To be Figure 4 The diagram shows a cross-sectional view of the first and second circuit boards after they are electrically connected by conductive paste.

[0021] Figure 6 In order to be in Figure 5 The diagram shows cross-sectional views of the first and second circuit boards after the receiving grooves have been formed.

[0022] Figure 7 In order to be in Figure 6 A schematic cross-sectional view of the circuit board assembly obtained after forming a fixed column in the receiving groove.

[0023] Figure 8 This is a cross-sectional schematic diagram of a circuit board assembly according to another embodiment of this application.

[0024] Figure 9 This is a schematic diagram of the structure of conductive paste and fixing posts arranged in accordance with an embodiment of this application.

[0025] Explanation of main component symbols

[0026] Circuit board assembly 100、100a First circuit board 10 First dielectric layer 11 First line layer 13 First covering layer 15 First opening 152 Through hole 17 First connection area 19 Second circuit board 20 Second dielectric layer 21 Second line layer 23 Second covering layer 25 Second opening 252 positioning groove 254 Second connection area 27 conductive paste 30 filler 35 Reception slot 40、40a Fixed column 45、45a Detailed Implementation

[0027] To better understand the above-mentioned objectives, features, and advantages of this application, the application will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. Many specific details are set forth in the following description to provide a thorough understanding of this application; the described embodiments are merely some, not all, of the embodiments described in this application.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. The term "and / or" as used herein includes all and any combination of one or more of the associated listed items.

[0029] In the various embodiments of this application, for ease of description and not limitation, the term "connection" used in the patent application specification and claims is not limited to physical or mechanical connections, whether direct or indirect. Terms such as "upper," "lower," "above," "below," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship also changes accordingly.

[0030] Please see Figures 1 to 7This application embodiment provides a method for manufacturing a circuit board assembly 100, which may include the following steps:

[0031] Step S1: Please refer to Figure 1 A first circuit board 10 having a first opening 152.

[0032] The first circuit board 10 includes a first dielectric layer 11, a first circuit layer 13, and a first cover layer 15. The first circuit layer 13 is located on the surface of the first dielectric layer 11, and the first cover layer 15 is located on the outermost layer of the first circuit board 10. The first cover layer 15 covers the first circuit layer 13 and the first dielectric layer 11 exposed to the first circuit layer 13.

[0033] The number of layers of the first dielectric layer 11 and the first circuit layer 13 is not limited. In this embodiment, the first dielectric layer 11 has one layer and the first circuit layer 13 has two layers. The two first circuit layers 13 are located on opposite surfaces of the first dielectric layer 11 and are electrically connected to each other.

[0034] The material of the first dielectric layer 11 can be selected from flexible materials such as polyimide (PI), liquid crystal polymer (LCP), and modified polyimide (MPI), or it can be selected from rigid materials such as polypropylene (PP) and polytetrafluoroethylene (PTFE).

[0035] A first opening 152 is formed on a first cover layer 15 located in a first connection area 19 of a first circuit board 10, and a first circuit layer 13 is exposed through the first opening 152. The first connection area 19 is the area of ​​the first circuit board 10 used for electrical connections. The first circuit layer 13 exposed through the first opening 152 is used for electrical connections. In this embodiment, the first opening 152 is formed on the surface of one of the first cover layers 15, and the first opening 152 penetrates the first cover layer 15.

[0036] The number and arrangement of the first opening 152 are not limited and can be set according to the actual electrical connection requirements.

[0037] Step S2: Please refer to Figure 2 This forms a through hole 17 that penetrates the first connecting area 19.

[0038] The through-hole 17 penetrates the first connection area 19 along the direction in which the first circuit board 10 is stacked. In this embodiment, the through-hole 17 penetrates the first cover layer 15, the first circuit layer 13, and the first dielectric layer 11.

[0039] The through-hole 17 is used for positioning in subsequent processes. The number and arrangement of the through-hole 17 are not limited and can be set according to actual positioning requirements.

[0040] Step S3: Please refer to Figure 3 A second circuit board 20 having a second opening 252.

[0041] The second circuit board 20 includes a second dielectric layer 21, a second circuit layer 23, and a second cover layer 25. The second circuit layer 23 is located on the surface of the second dielectric layer 21, and the second cover layer 25 is located on the outermost layer of the second circuit board 20. The second cover layer 25 covers the second circuit layer 23 and the second dielectric layer 21 exposed to the second circuit layer 23.

[0042] The material of the second dielectric layer 21 can be selected from flexible materials or rigid materials. The number of layers of the second dielectric layer 21 and the second circuit layer 23 is also not limited.

[0043] The second opening 252 is located on the second cover layer 25 of the second connection area 27 of the second circuit board 20, and the second wiring layer 23 is exposed through the second opening 252. The second connection area 27 is the area of ​​the second circuit board 20 used for electrical connection with the first circuit board 10. The second wiring layer 23 exposed through the second opening 252 is used for electrical connection. In this embodiment, the second opening 252 is formed on the surface of one of the second cover layers 25, and the second opening 252 penetrates the second cover layer 25.

[0044] The number of second openings 252 is the same as the number of first openings 152. The position of each second opening 252 corresponds to the position of a first opening 152.

[0045] The second circuit board 20 also includes a positioning groove 254, which is located in the second connection area 27 and on the same side of the second circuit board 20 as the second opening 252. The depth of the positioning groove 254 in the second connection area 27 is not limited. For example, the positioning groove 254 may be formed on the second cover layer 25 but not penetrating it, it may penetrate the second cover layer 25, it may penetrate the second cover layer 25 and be formed on the second circuit layer 23, it may penetrate both the second cover layer 25 and the second circuit layer 23, or it may penetrate both the second cover layer 25 and the second circuit layer 23 and be formed on the second dielectric layer 21. In this embodiment, the positioning groove 254 penetrates the second cover layer 25, and the second circuit layer 23 is exposed to the second cover layer 25.

[0046] The number of positioning slots 254 is the same as the number of through holes 17. The position of each positioning slot 254 corresponds to the position of one through hole 17.

[0047] Step S4: Please refer to Figure 4 and Figure 5 Conductive paste 30 is applied between the first connection area 19 and the second connection area 27 to electrically connect the first circuit board 10 and the second circuit board 20.

[0048] Conductive paste 30 is disposed in the first opening 152 and / or the second opening 252, the first connection area 19 is attached to the second connection area 27, and the positions of the conductive paste 30 in the first opening 152 and the second opening 252 correspond. After the first circuit board 10 and the second circuit board 20 are attached, they are placed in a reflow oven so that the conductive paste 30 melts and fully fills the first opening 152 and the second opening 252, and then solidifies to connect the first circuit layer 13 exposed in the first opening 152 and the second circuit layer 23 exposed in the second opening 252, thereby realizing the electrical connection between the first circuit board 10 and the second circuit board 20.

[0049] Before attaching the first connecting area 19 to the second connecting area 27, filler 35 is filled into the positioning groove 254. The color of filler 35 is different from the color of the surface of the first connecting area 19. During the process of attaching the first connecting area 19 to the second connecting area 27, because the color of filler 35 is different from the surface of the first connecting area 19, filler 35 in the positioning groove 254 can play an alignment role, so that the first connecting area 19 and the second connecting area 27 are accurately aligned. After attaching the first connecting area 19 to the second connecting area 27, observing through the through hole 17 along the direction from the first connecting area 19 to the second connecting area 27, filler 35 in the positioning groove 254 can be identified, so that the position of the through hole 17 corresponds to the position of the positioning groove 254, and the positions of the first opening 152 and the second opening 252 also correspond to each other.

[0050] The material of filler 35 can be the same as that of conductive paste 30.

[0051] The distance between the filler 35 and the conductive paste 30 can be greater than or equal to 50 μm to match the printing accuracy of the conductive paste 30.

[0052] Step S5: Please refer to Figure 6 A receiving slot 40 is formed in the first connecting area 19 and the second connecting area 27, the receiving slot 40 passing through the first connecting area 19 and extending to at least a portion of the second connecting area 27.

[0053] A receiving groove 40 is formed in the area where the through hole 17 is located, so as to facilitate the formation of the receiving groove 40 in the preset area.

[0054] Along the direction perpendicular to the stacked arrangement of the first circuit board 10 and the second circuit board 20, the diameter of the positioning groove 254 is larger than the diameter of the through hole 17. The through hole 17 is used for alignment, and the positioning groove 254 is used to accommodate the filler 35, so that the positioning groove 254 can accommodate more filler 35. The filler 35 can move toward the through hole 17 and be accommodated in the through hole 17. The filler 35 can also further play an alignment role, so as to identify the area where the through hole 17 is located in the process of forming the receiving groove 40, which is conducive to more accurately forming the receiving groove 40 in the preset area.

[0055] In some embodiments, the aperture of the positioning groove 254 is 300μm-400μm, and the aperture of the through hole 17 is 100μm-200μm.

[0056] Step S6: Please refer to Figure 7 Insulating material is filled into the receiving groove 40 to form a fixing post 45, thereby obtaining the circuit board assembly 100.

[0057] The insulating material can be resin, such as epoxy resin. The fixing post 45 can be used to strengthen the connection between the first circuit board 10 and the second circuit board 20.

[0058] When the receiving groove 40 is a through hole, the fixing post 45 formed in the receiving groove 40 penetrates the first circuit board 10 and the second circuit board 20. The connection area between the fixing post 45 and the first circuit board 10 and the second circuit board 20 is large, which is conducive to further improving the connection strength between the first circuit board 10 and the second circuit board 20.

[0059] In this embodiment, the receiving groove 40 can be a through hole that simultaneously penetrates the first connection area 19 and the second connection area 27. In the circuit board assembly 100, the fixing post 45 penetrates both the first connection area 19 and the second connection area 27.

[0060] Please see Figure 8 In other embodiments, the receiving groove 40a may also be a blind hole that passes through the first connection area 19 and is opened in the second connection area 27. In this case, in the circuit board assembly 100a, the fixing post 45a passes through the first connection area 19 and extends to a portion of the second connection area 27.

[0061] Please see Figure 7 The present application embodiment also includes a circuit board assembly 100, which may include a first circuit board 10, a second circuit board 20, conductive paste 30 and a fixing post 45. The conductive paste 30 electrically connects the first circuit board 10 and the second circuit board 20 so that the first circuit board 10 and the second circuit board 20 are electrically connected. The fixing post 45 passes through the first circuit board 10 and is accommodated in at least a portion of the second circuit board 20 to enhance the connection strength between the first circuit board 10 and the second circuit board 20.

[0062] The first circuit board 10 includes a first connection area 19, and the second circuit board 20 includes a second connection area 27. The first connection area 19 and the second connection area 27 are stacked. Conductive paste 30 is disposed between the first connection area 19 and the second connection area 27. The conductive paste 30 is connected to the first circuit layer 13 located in the first connection area 19 and also connected to the second circuit layer 23 located in the second connection area 27, thereby realizing the electrical connection between the first circuit board 10 and the second circuit board 20.

[0063] In some embodiments, the fixing post 45 may extend through both the first connecting region 19 and the second connecting region 27. See also... Figure 8 In other embodiments, the fixing post 45a may penetrate through the first connection area 19 and extend into a portion of the second connection area 27.

[0064] The circuit board assembly 100 also includes a filler 35, which is located between the first connection area 19 and the second connection area 27. The filler 35 surrounds the fixing post 45, that is, the fixing post 45 passes through the filler 35.

[0065] The material of filler 35 can be the same as that of conductive paste 30. The distance between filler 35 and conductive paste 30 is greater than or equal to 50 μm.

[0066] Please see Figure 9 The number and arrangement of the fixing posts 45 and the conductive paste 30 can be set according to actual needs. For example, the fixing posts 45 and the conductive paste 30 can both be arranged in a straight line, such as... Figure 9 (a) and (b) in the diagram; the fixing post 45 is located on one side of the conductive paste 30, as shown in (a) and (b). Figure 9 (c) in the middle; or fixing post 45 partially surrounds conductive paste 30; or fixing post 45 fully surrounds conductive paste 30, such as Figure 9 (d) in the middle.

[0067] The method for manufacturing the circuit board assembly 100 in this application embodiment first provides conductive paste 30 for electrical connection between the first circuit board 10 and the second circuit board 20, and then forms a fixing post 45 for fixing. That is, it first goes through a high temperature and high pressure step, so it has no effect on the fixing effect of the subsequently formed fixing post 45, that is, it will not reduce the connection performance of the fixing post 45.

[0068] The above embodiments are only used to illustrate the technical solutions of this application and are not intended to limit it. Although this application has been described in detail with reference to the above preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions to the technical solutions of this application should not depart from the spirit and scope of the technical solutions of this application.

Claims

1. A method for manufacturing a circuit board assembly, characterized in that, Includes the following steps: A first circuit board is provided, the first circuit board including a first circuit layer, a first connection area of ​​the first circuit board having a first opening, and the first circuit layer being exposed to the first opening; A through-hole is formed on the first circuit board, penetrating the first connection area; A second circuit board is provided, the second circuit board including a second circuit layer, a second connection area of ​​the second circuit board having a second opening and a positioning groove, and the second circuit layer being exposed to the second opening; The positioning groove is filled with a filler, the color of which is different from the color of the surface of the first connection area; Conductive paste is disposed in the first opening and / or the second opening, and the first connection area and the second connection area are stacked together, with a portion of the second connection area exposed to the through hole, and the filler is moved toward the through hole and accommodated in the through hole; The conductive paste is melted and then solidified to electrically connect the first circuit board and the second circuit board. A receiving groove is formed in the region corresponding to the through hole, the receiving groove passing through the first connection area and extending to at least a portion of the second connection area; as well as Insulating material is filled into the receiving groove to form a fixed column.

2. The method for manufacturing a circuit board assembly according to claim 1, characterized in that, Along a direction perpendicular to the stacked arrangement of the first and second circuit boards, the diameter of the positioning groove is larger than the diameter of the through hole, and the filler is also accommodated in the through hole.

3. The method for manufacturing a circuit board assembly according to claim 1 or 2, characterized in that, The filler is made of the same material as the conductive paste.

4. A circuit board assembly manufactured by the method of manufacturing a circuit board assembly according to any one of claims 1-3, characterized in that, include: A first circuit board includes a first connection area and a first circuit layer, wherein the first connection area is provided with a first opening and the first circuit layer is exposed to the first opening; The second circuit board includes a second connection area and a second circuit layer. The second connection area is provided with a second opening, and the second circuit layer is exposed to the second opening. The first connection area and the second connection area are stacked together. Conductive paste is applied between the first connection area and the second connection area, and connects the first circuit layer and the second circuit layer to make the first circuit board and the second circuit board electrically connected. as well as A fixing post extends through the first connection area and is disposed in at least a portion of the second connection area to fix the first circuit board and the second circuit board.

5. The circuit board assembly according to claim 4, characterized in that, The fixed column passes through both the first connection area and the second connection area.

6. The circuit board assembly according to claim 4, characterized in that, The circuit board assembly also includes a filler material located between the first connection area and the second connection area, and surrounding the fixing post.

7. The circuit board assembly according to claim 6, characterized in that, The filler is made of the same material as the conductive paste.

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