Circuit board structure, manufacturing method thereof and applied three-dimensional electrical connection structure

Abstract

The invention discloses a circuit board structure, a manufacturing method thereof and a three-dimensional electrical connection structure applied by the circuit board structure. The circuit board structure comprises a flexible base material core board, a first circuit layer, a first solder mask layer, a first protective layer, a rigid board and a plurality of conductors. The flexible base material core plate has flexibility and comprises a first surface and a second surface. The first circuit layer is arranged on the first surface and is provided with a plurality of electric connecting parts; the first circuit layer and the first surface are coated with the first solder mask layer, and the first solder mask layer is provided with a plurality of hollow parts which are aligned with the electrical connection parts. The first protection layer is arranged on the first solder mask, and the surface of the first protection layer is a flat surface. The rigid plate is disposed on the first solder mask and corresponds to the hollow portion. The plurality of conductors are respectively formed on the electrical connection parts and are exposed from the hollow parts.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of circuit board, and in particular to a circuit board structure with a core board formed of a flexible substrate, a manufacturing method thereof and a three-dimensional electrical connection structure applied thereto. BACKGROUND

[0002] Circuit boards are used to carry electronic components and form electrical connections between the electronic components via conductive layers to form traces, and the electronic components transmit signals or supply power to each other via the circuit board to complete a specific function. Most existing circuit boards are made of rigid substrates formed of glass fibers and epoxy resin as core boards, so that in order to achieve electrical connection between two circuit boards with different heights or between a circuit board and an electronic component, a cable or a flexible circuit board (FPC) that can be bent must be used.

[0003] Therefore, in addition to the circuit board, various wires or flexible circuit boards must also be produced, which increases the complexity of the internal configuration of the electronic device, and the variety of electronic components also increases the cost of manufacturing and management. SUMMARY

[0004] Therefore, the present application aims to provide a circuit board structure, a manufacturing method thereof and a three-dimensional electrical connection structure applied thereto, which solves the problem of the complexity of the configuration of the electronic device and the increase in the cost of manufacturing and management caused by the use of cables or flexible circuit boards to connect two circuit boards with different heights or electronic components.

[0005] The present application provides a circuit board structure, which includes a flexible substrate core board, a first circuit layer, a first solder resist layer, a first protective layer, a rigid plate and a plurality of conductors. The flexible substrate core board is flexible and includes a first surface and a second surface. The first circuit layer is disposed on the first surface, and the first circuit layer has a plurality of electrical connection portions. The first solder resist layer is coated on the first circuit layer and the first surface, and the first solder resist layer has a plurality of through-holes, which are aligned with the electrical connection portions. The first protective layer is disposed on the first solder resist layer, and the surface of the first protective layer is a flat surface. The rigid plate is disposed on the first solder resist layer and corresponds to the through-holes. The plurality of conductors are respectively formed in the electrical connection portions and exposed from the through-holes.

[0006] The present application also provides a manufacturing method of the circuit board structure, which comprises the following steps: providing a circuit board substrate, which comprises a flexible substrate core plate and a first conductor layer arranged on a first surface of the flexible substrate core plate; forming a first circuit layer on the first conductor layer, the first circuit layer having a plurality of electrical connection portions; applying a first solder resist layer on the first circuit layer and the first surface, the first solder resist layer having a plurality of through-holes, the plurality of through-holes being aligned with the plurality of electrical connection portions; bonding a first protective layer to the first solder resist layer, the surface of the first protective layer being a flat surface; bonding a rigid plate to the second surface; and depositing a plurality of conductive bodies on the plurality of electrical connection portions by a chemical deposition process, and exposing the plurality of conductive bodies from the plurality of through-holes.

[0007] The present application also provides a three-dimensional electrical connection structure, which comprises a first circuit board, a second circuit board and a connection circuit board. The first circuit board is arranged at a first position, and the first position has a first height. The second circuit board is arranged at a second position, and the second position has a second height. The connection circuit board connects the first circuit board and the second circuit board. The first circuit board, the second circuit board and the connection circuit board are integrated, and the first circuit board, the second circuit board and the connection circuit board have the above-mentioned circuit board structure.

[0008] The circuit board structure provided by the present application can realize an integrated three-dimensional electrical connection structure, and does not need to arrange cables or flexible circuit boards, so that the internal configuration of an electronic device can be simplified, and the manufacturing cost and management cost can be greatly reduced. BRIEF DESCRIPTION OF DRAWINGS

[0009] Figures 1 to 11 FIG. 1 is a schematic diagram of an embodiment of the manufacturing method of the circuit board structure of the present application.

[0010] Figure 12 FIG. 2 is a schematic diagram of an embodiment of the circuit board structure of the present application.

[0011] Figures 13 to 25 FIG. 3 is a schematic diagram of another embodiment of the manufacturing method of the circuit board structure of the present application.

[0012] Figures 26 to 35 FIG. 4 is a schematic diagram of still another embodiment of the manufacturing method of the circuit board structure of the present application.

[0013] Figure 36 FIG. 5 is a schematic diagram of an embodiment of the three-dimensional electrical connection structure of the present application.

[0014] Explanation of reference numerals in the attached drawings: 10-Circuit board substrate; 10a-Core board; 10b-First surface; 10c-Second surface; 11-First conductor layer; 12-Photoresist layer; 13-First circuit layer; 14-First solder mask layer; 15-First protective layer; 16-Rigid substrate; 17-Conductor; 18-First insulating layer; 19-Third conductor layer; 19a-Third circuit layer; 21-Second conductor layer; 23-Second circuit layer; 25-Second protective layer; 28-Second insulating layer; 29-Fourth conductor layer; 29a-Fourth circuit layer; 100-First circuit board; 131-Electrical connection part; 141-Opening part; 200-Second circuit board; 300-Connecting circuit board; H-Through hole; H1-Through hole; H2-Blind hole; M-Photomask. Detailed Implementation

[0015] Please see Figures 1 to 11 This illustrates an embodiment of a method for manufacturing a circuit board structure according to the present invention. The circuit board structure in this embodiment is a single-conductor-layer circuit board. For example... Figure 1 As shown, a circuit board substrate 10 is provided. The circuit board substrate 10 includes a core board 10a and a first conductor layer 11 pre-pressed onto a first surface 10b of the core board 10a. In this embodiment, the core board 10a is made of a flexible material, and the first conductor layer 11 is a copper foil layer. Next, as... Figure 2 As shown, a photoresist layer 12 is coated on the first conductor layer 11. Then, as... Figure 3 As shown, the photoresist layer 12 is exposed using a photomask M corresponding to the circuit diagram, causing the portion of the photoresist layer 12 corresponding to the circuit to harden. Then, as... Figure 4 As shown, the uncured photoresist layer 12 is removed, so that the portion corresponding to the circuit is covered by the cured photoresist layer 12, while the first conductor layer 11, which does not correspond to the circuit, is exposed from the photoresist layer 12. Figure 5 As shown, the first conductor layer 11 exposed from the photoresist layer 12 is removed using an etching process. Figure 6 As shown, the photoresist layer 12 is removed to obtain the first circuit layer 13. Figure 7 As shown, a first solder mask layer 14 is applied to the first circuit layer 13. Then, as... Figure 8 As shown, the first solder mask layer 14 corresponding to the electrical connection portion 131 on the first circuit layer 13 is removed to form a transparent portion 141. The electrical connection portion 131 may be a gold finger structure for insertion with an electrical connector or a solder pad structure for soldering the pins of electronic components.

[0016] Then as Figure 9As shown, a high-temperature resistant adhesive film is pressed onto the surface of the first solder resist layer 14 to form a first protective layer 15. The surface of the first protective layer 15 is flat, and the first protective layer 15 fills the unevenness of the first solder resist layer 14 caused by the height difference between the first circuit layer 13 and the first surface 10b of the core board 10a, so that a completely flat surface is finally formed. The range of the first protective layer 15 does not extend beyond the first solder resist layer 14 where the electrical connection portion 131 of the first circuit layer 13 is located.

[0017] Then as Figure 10 As shown, a rigid plate 16 is bonded to the second surface 10c of the core material 10a, and is located at a position corresponding to the electrical connection portion 131 of the first circuit layer 13. The rigid plate 16 can reinforce the edge of the core material 10a and serve as a plug-in structure.

[0018] Finally, as Figure 11 As shown, a conductor 17 is deposited on the electrical connection portion 131 of the first circuit layer 13 using a chemical deposition process. The conductor 17 is exposed from the opening portion 141 of the first solder mask layer 14, enabling it to form an electrical connection with electronic components. In this embodiment, the conductor 17 is formed of gold (Au). In this embodiment, the electrical connection portion 131 is formed on the edge of the core board 10a and, in conjunction with the conductor 17, forms a gold finger structure for insertion.

[0019] Please see Figure 12 This illustrates an embodiment of the circuit board structure of the present invention, wherein the circuit board structure is cut to a desired size and shape. The conductor 17 is located at the edge of the circuit board structure, the first solder mask layer 14 surrounds the conductor 17, and the edge of the first protective layer 15 is close to the conductor 17 but not beyond the position of the conductor 17.

[0020] Please see Figures 13 to 24 This is another embodiment of the method for manufacturing the circuit board structure of the present invention. The circuit board structure in this embodiment is a circuit board with two conductor layers. For example... Figure 13 As shown, a circuit board substrate 10 is provided. The circuit board substrate 10 includes a core board 10a, a first conductor layer 11 pre-attached to a first surface 10b of the core board 10a, and a second conductor layer 21 pre-attached to a second surface 10c of the core board 10a. In this embodiment, the core board 10a is made of a flexible material. The first conductor layer 11 and the second conductor layer 21 are copper foil layers. Next, as... Figure 14 As shown, a through-hole H is formed by drilling, and then a conductor is plated onto the wall of the through-hole H by electroplating, so that the first conductor layer 11 and the second conductor layer 21 are connected. Then, as... Figure 15 As shown, a photoresist layer 12 is coated on the first conductor layer 11. Then, as... Figure 16As shown, the photoresist layer 12 is exposed using a photomask M corresponding to the circuit diagram, causing the portion of the photoresist layer 12 corresponding to the circuit to harden. Then, as... Figure 17 As shown, the uncured photoresist layer 12 is removed, so that the portion corresponding to the circuit is covered by the cured photoresist layer 12, while the first conductor layer 11, which does not correspond to the circuit, is exposed from the photoresist layer 12. Figure 18 As shown, the first conductor layer 11 exposed from the photoresist layer 12 is removed using an etching process. Figure 19 As shown, the photoresist layer 12 is removed to obtain the first circuit layer 13.

[0021] like Figure 20 As shown, a second circuit layer 23 is formed on the second conductor layer 21 using the same process. Then, as... Figure 21 As shown, a first solder mask 14 is coated on the first circuit layer 13, and a second solder mask 24 is coated on the second circuit layer 23. Then as... Figure 22 As shown, the first solder mask layer 14 corresponding to the electrical connection portion 131 on the first circuit layer 13 is removed to form a transparent portion 141. The electrical connection portion 131 may be a gold finger structure for insertion with an electrical connector or a solder pad structure for soldering the pins of electronic components.

[0022] Then as Figure 23 As shown, a first protective layer 15 is formed by pressing a high-temperature resistant adhesive film onto the surface of the first solder resist layer 14. The surface of the first protective layer 15 is flat, and the first protective layer 15 fills the unevenness of the first solder resist layer 14 caused by the height difference between the first circuit layer 13 and the first surface 10b of the core board 10a, so that a completely flat surface is finally formed. The area of ​​the first protective layer 15 does not extend beyond the first solder resist layer 14 where the electrical connection portion 131 of the first circuit layer 13 is located. Similarly, a second protective layer 25 is formed by pressing a high-temperature resistant adhesive film onto the surface of the second solder resist layer 24.

[0023] Then as Figure 24 As shown, a rigid plate 16 is bonded to the second protective layer 25 and is positioned corresponding to the electrical connection portion 131 of the first circuit layer 13. The rigid plate 16 can reinforce the edge of the core material 10a to serve as a plug-in structure.

[0024] Finally, as Figure 25 As shown, a conductor 17 is deposited on the electrical connection portion 131 of the first circuit layer 13 using a chemical deposition process. The conductor 17 is exposed from the opening portion 141 of the first solder mask layer 14, enabling it to form an electrical connection with electronic components. In this embodiment, the conductor 17 is formed of gold (Au). In this embodiment, the electrical connection portion 131 is formed on the edge of the core board 10a and, in conjunction with the conductor 17, forms a gold finger structure for insertion.

[0025] Please seeFigures 26 to 35 which is yet another embodiment of the manufacturing method of the circuit board structure of the present application. As shown in Figure 26 , a circuit board structure as shown in Figure 20 is provided, which has a core board 10a and a first circuit layer 13 formed on a first surface 10b of the core board 10a and a second circuit layer 23 formed on a second surface 10c of the core board 10a. Then as shown in Figure 27 and Figure 28 , a first insulating layer 18 and a third conductor layer 19 are attached on the first circuit layer 13, and a second insulating layer 28 and a fourth conductor layer 29 are attached on the second circuit layer 23, the first insulating layer 18 and the second insulating layer 28 are polypropylene (PP) boards, and the third conductor layer 19 and the fourth conductor layer 29 are copper foil layers.

[0026] Then as shown in Figure 29 , through holes Hl and blind holes H2 are formed on the circuit board structure by drilling process, and the through holes H previously formed through the core board 10a, the first circuit layer 13 and the second circuit layer 23 become buried holes. Then a conductor is formed on the hole walls of the through holes Hl and the blind holes H2 by electroplating process to connect the first circuit layer 13 and the third conductor layer 19, the second circuit layer 23 and the fourth conductor layer 29 or / and the third conductor layer 19, the first circuit layer 13, the second circuit layer 23 and the fourth conductor layer 29.

[0027] Then as shown in Figure 30 , a third circuit layer 19a is formed on the third conductor layer 19, and a fourth circuit layer 29a is formed on the fourth conductor layer 29. Then as shown in Figure 31 , a first solder resist layer 14 is coated on the third circuit layer 19a, and a second solder resist layer 24 is coated on the fourth circuit layer 29a. Then as shown in Figure 32 , the first solder resist layer 14 on the third circuit layer 19a is removed to form a transparent part 141 corresponding to an electrical connection part 191. The electrical connection part 191 can be a gold finger structure for plugging with an electrical connector or a pad structure for soldering with an electronic component.

[0028] Then as shown in Figure 33 , a first protective layer 15 is formed by attaching a high-temperature resistant adhesive film on the surface of the first solder resist layer 14. The surface of the first protective layer 15 is flat, and the first protective layer 15 fills the uneven state of the first solder resist layer 14 caused by the height difference between the third circuit layer 19a and the first insulating layer 18, so that a completely flat surface is finally formed. The range of the first protective layer 15 does not reach the first solder resist layer 14 where the electrical connection part 191 of the third circuit layer 19a is located. Similarly, a second protective layer 25 is formed by attaching a high-temperature resistant adhesive film on the surface of the second solder resist layer 24.

[0029] Then as shown in Figure 34As shown, a rigid plate 16 is bonded to the second protective layer 25 and is positioned corresponding to the electrical connection portion 131 of the first circuit layer 13. The rigid plate 16 can reinforce the edge of the core material 10a to serve as a plug-in structure.

[0030] Finally, as Figure 35 As shown, a conductor 17 is deposited on the electrical connection portion 191 of the third circuit layer 19a using a chemical deposition process. The conductor 17 is exposed from the opening portion 141 of the first solder mask layer 14, enabling it to form an electrical connection with electronic components. In this embodiment, the conductor 17 is formed of gold (Au). In this embodiment, the electrical connection portion 191 is formed on the edge of the core board 10a and, in conjunction with the conductor 17, forms a gold finger structure for insertion.

[0031] Please see Figure 36 This illustrates an embodiment of the three-dimensional electrical connection structure of the present invention. The three-dimensional electrical connection structure of this embodiment includes a first circuit board 100, a second circuit board 200, and a connecting circuit board 300. The first circuit board 100 is disposed at a first position, having a first height. The second circuit board 200 is disposed at a second position, having a second height. The first and second heights are relative to a reference plane, such as the bottom of an electronic device casing. The first height may be the same as or different from the second height. The connecting circuit board 300 connects the first circuit board 100 and the second circuit board 200. The first circuit board 100, the second circuit board 200, and the connecting circuit board 300 are an integrated structure, and the first circuit board 100, the second circuit board 200, and the connecting circuit board 300 have the aforementioned circuit board structure. That is, in the above manufacturing method, after the circuit board structure is completed, it can be cut into the desired shape and size according to the designed configuration. The first circuit board 100 and the second circuit board 200 can be used to carry electronic components, and the connecting circuit board 300 has lines connecting the first circuit board 100 and the second circuit board 200.

[0032] The circuit board structure provided by this invention can realize an integrated three-dimensional electrical connection structure without the need for cables or flexible circuit boards, thereby simplifying the internal configuration of electronic devices and significantly reducing manufacturing and management costs.

[0033] The above descriptions are only the preferred embodiment of the present application, and are not intended to limit the scope of the present application, which is defined by the appended claims and their equivalents. In addition, any embodiment or claim of the present application does not need to achieve all the purposes or advantages or features provided by the present application. Furthermore, the abstract and title are only used to assist patent document search, and are not intended to limit the scope of the present application. In addition, the terms "first", "second", etc. mentioned in the specification or claims are only used to name elements or distinguish different embodiments or ranges, and are not intended to limit the upper or lower limit of the number of elements.

Claims

1. A circuit board structure, characterized in that, include: A flexible substrate core board, which is flexible and includes a first surface and a second surface; A first circuit layer is disposed on the first surface, the first circuit layer having a plurality of electrical connection portions; A first solder resist layer is coated on the first circuit layer and the first surface. The first solder resist layer has a plurality of open portions, which are aligned with the plurality of electrical connection portions. A first protective layer is disposed on the first solder resist layer, and the surface of the first protective layer is a flat surface; A rigid plate is disposed on the first surface; as well as Multiple conductors are formed in the multiple electrical connection portions and exposed from the multiple open portions.

2. A circuit board structure, characterized in that, include: A flexible substrate core board, which is flexible and includes a first surface and a second surface; A first circuit layer is disposed on the first surface, the first circuit layer having a plurality of electrical connection portions; A second circuit layer is disposed on the second surface; A first solder resist layer is coated on the first circuit layer and the first surface. The first solder resist layer has a plurality of open portions, which are aligned with the plurality of electrical connection portions. A second solder resist layer is applied to the second circuit layer and the second surface; A first protective layer is disposed on the first solder resist layer, and the surface of the first protective layer is a flat surface; A second protective layer is disposed on the second solder resist layer, and the surface of the second protective layer is a flat surface; A rigid plate is disposed on the second protective layer; as well as Multiple conductors are formed in the multiple electrical connection portions and exposed from the multiple open portions.

3. The circuit board structure as described in claim 1 or 2, characterized in that, The first circuit layer is formed of copper, the plurality of conductors are formed of gold, and the first protective layer is a high-temperature resistant adhesive film.

4. A circuit board structure, characterized in that, include: A flexible substrate core board, which is flexible and includes a first surface and a second surface; A first circuit layer is disposed on the first surface; A second circuit layer is disposed on the second surface; A first insulating layer is disposed on the first circuit layer; A third circuit layer is disposed on the first insulating layer, the first circuit layer having multiple electrical connection portions; A second insulating layer is disposed on the second circuit layer; A fourth circuit layer is disposed on the second insulation layer; A first solder resist layer is coated on the third circuit layer and the first insulating layer. The first solder resist layer has a plurality of open portions, which are aligned with the plurality of electrical connection portions. A first protective layer is disposed on the first solder resist layer, and the surface of the first protective layer is a flat surface; A second solder resist layer is applied to the second circuit layer and the second surface; A second protective layer is disposed on the second solder resist layer, and the surface of the second protective layer is a flat surface; A rigid plate is disposed on the second protective layer; as well as Multiple conductors are formed in the multiple electrical connection portions and exposed from the multiple open portions.

5. A method for manufacturing a circuit board structure, characterized in that, include: A circuit board substrate is provided, which includes a flexible substrate core board and a first conductor layer disposed on a first surface of the flexible substrate core board; A first circuit layer is formed in the first conductor layer, and the first circuit layer has a plurality of electrical connections; A first solder resist layer is coated on the first circuit layer and the first surface. The first solder resist layer has a plurality of open portions, which are aligned with the plurality of electrical connection portions. A first protective layer is bonded to the first solder resist layer, wherein the surface of the first protective layer is a flat surface; A rigid sheet is bonded to the second surface; Multiple conductors are deposited in the multiple electrical connection portions using a chemical deposition process, and the multiple conductors are exposed from the multiple open portions.

6. A method for manufacturing a circuit board structure, characterized in that, include: A circuit board substrate is provided, which includes a flexible substrate core board, a first conductor layer disposed on a first surface of the flexible substrate core board, and a second conductor layer disposed on a second surface of the flexible substrate core board. A first circuit layer is formed in the first conductor layer, and the first circuit layer has a plurality of electrical connections; A second circuit layer is formed on the second conductor layer; A first solder resist layer is coated on the first circuit layer and the first surface. The first solder resist layer has a plurality of open portions, which are aligned with the plurality of electrical connection portions. A second solder resist layer is applied to the second circuit layer and the second surface. A first protective layer is bonded to the first solder resist layer, wherein the surface of the first protective layer is a flat surface; A second protective layer is bonded to the second solder resist layer, the surface of the second protective layer being a flat surface; A rigid sheet is bonded to the second protective layer; Multiple conductors are deposited in the multiple electrical connection portions using a chemical deposition process, and the multiple conductors are exposed from the multiple open portions.

7. The method for manufacturing the circuit board structure as described in claim 6, characterized in that, The first protective layer and the second protective layer are bonded to the first solder resist layer and the second solder resist layer by a high-temperature resistant adhesive film through a hot-pressing process.

8. A method for manufacturing a circuit board structure, characterized in that, include: A circuit board substrate is provided, which includes a flexible substrate core board, a first conductor layer disposed on a first surface of the flexible substrate core board, and a second conductor layer disposed on a second surface of the flexible substrate core board. A first circuit layer is formed in the first conductor layer; A second circuit layer is formed on the second conductor layer; A first insulating layer, a third conductor layer, a second insulating layer, and a fourth conductor layer are provided; The first insulating layer is bonded to the first circuit layer and the first surface, and the second insulating layer is bonded to the second circuit layer and the second surface; The third conductor layer is bonded to the first insulating layer, and the fourth conductor layer is bonded to the second insulating layer; A third circuit layer is formed in the third conductor layer, the third circuit layer having multiple electrical connections, and a fourth circuit layer is formed in the fourth conductor layer; A first solder resist layer is coated on the third circuit layer. The first solder resist layer has a plurality of open portions, which are aligned with the plurality of electrical connection portions. A second solder resist layer is applied to the fourth circuit layer; A rigid sheet is bonded to the second protective layer; Multiple conductors are deposited in the multiple electrical connection portions using a chemical deposition process, and the multiple conductors are exposed from the multiple open portions.

9. A three-dimensional electrical connection structure, characterized in that, include: A first circuit board is disposed at a first position, the first position having a first height; A second circuit board is disposed at a second position, the second position having a second height; A connecting circuit board that connects the first circuit board and the second circuit board; The first circuit board, the second circuit board, and the connecting circuit board are an integrated structure, and the first circuit board, the second circuit board, and the connecting circuit board have the circuit board structure as described in any one of claims 1 to 4.

10. The three-dimensional electrical connection structure as described in claim 9, characterized in that, The first height is not equal to the second height.

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