TWI473545B - Combination of Flexible Circuit Board and Hard Circuit Board and Its Method - Google Patents

Description

Combination of flexible circuit board and hard circuit board and preparation method thereof

The invention relates to a combination of two circuit boards and a manufacturing method thereof, in particular to a combination of a flexible printed circuit (FPC) and a printed circuit board (PCB) and a manufacturing method thereof.

Referring to FIG. 11 , in the field of circuit board application, the combination of the flexible circuit board 60 and the rigid circuit board 70 adopts a male-female buckle assembly method: the male fastener 80 is riveted to the flexible circuit board with the fixture. 60, the male fastener 80 is internally provided with a conductive portion, so that the conductive portion of the male fastener 80 is spot-welded to the flexible circuit board 60, and is electrically connected to the flexible circuit board 60; and the female fastener 90 is used as a jig. Riveted to the hard circuit board 70, the female fastener 90 is also internally provided with a conductive portion, and the conductive portion of the female fastener 90 is also electrically connected to the hard circuit board 70 by spot welding; 80 is fastened to the female fastener 90. At this time, the conductive portion of the male fastener 80 is in contact with the conductive portion of the female fastener 90, so that the flexible circuit board 60 and the rigid circuit board 70 are transmitted through the male fastener 80. The female circuit board 90 is integrated with the female fastener 90, and the flexible circuit board 60 and the rigid circuit board 70 are electrically connected through the conductive portion of the male fastener 80 and the conductive portion of the female fastener 90.

However, the male and female fastener components are required to be purchased separately, and the corresponding fixtures also have specific specifications, if they are to be used with the flexible circuits used. The design of the board 60 and the rigid circuit board 70 replaces the appropriate male and female buckle components, and the corresponding fixtures must be purchased and used at the same time, so that the cost of the process will be greatly improved; on the other hand, the male and female buckles The components have a certain size, and after being mounted on the flexible circuit board 60 and the hard circuit board 70, the volume of the flexible circuit board 60 and the hard circuit board 70 will be increased, particularly the flexible circuit board 60 and the hard circuit board 70. At the junction, the thickness thereof will be greatly increased. Therefore, when applied, a large space is required to accommodate the combined flexible circuit board 60 and the hard circuit board 70, thereby affecting the combined flexible circuit board 60. And the applicability of the rigid circuit board 70.

In view of the above-mentioned shortcomings of the prior art, an object of the present invention is to provide a method for manufacturing a combination of a flexible circuit board and a rigid circuit board, which has the advantages of low manufacturing cost, and the combined system produced thereby has no space. More extensive applicability.

In order to achieve the foregoing object, the technical means adopted by the present invention is a method for manufacturing a combination of the flexible circuit board and the rigid circuit board, the steps comprising: providing a rigid circuit board: the hard circuit board includes a body; a flexible circuit board: the body of the flexible circuit board has a first side and a second side, and a through hole is formed through the body; a solder layer is disposed: a solder layer is formed on the body of the hard circuit board and the softness Between the first side of the body of the circuit board, and the solder layer is located at the via hole of the flexible circuit board; the heat fusion type bonding: providing a heating source to the second side of the body of the flexible circuit board to make it pass through The hole solder layer is hot melted to remove the heating After the source is cured, the solder layer is solidified between the body of the rigid circuit board and the body of the flexible circuit board, and the hard circuit board and the flexible circuit board are joined via the solder layer.

The invention further relates to a combination of a flexible circuit board and a rigid circuit board, comprising: a rigid circuit board comprising a body; a flexible circuit board comprising a body and a through hole, the body having a first side and a In a second side, the via hole is formed on the body; a solder layer is thermally melted between the body of the hard circuit board and the body of the flexible circuit board, and the solder layer is located at the via hole of the flexible circuit board.

In the present invention, the combination of the flexible circuit board and the rigid circuit board is formed by the via hole, and the thermal energy can pass through the via hole to reach the solder layer between the flexible circuit board and the hard circuit board, so that The solder layer is hot melted and shaped so that the softness and hard board are combined through the heat-fusible solder layer without the need to use any additional components and their fixtures, thereby reducing process cost and solder layer thickness It is relatively thin, so that the combined body produced by the above-described production method does not occupy a space, and has a wide applicability.

Further, between the step of providing a flexible circuit board and the step of disposing a solder layer, further comprising the step of forming a metal heat conducting layer: forming the metal heat conducting layer on the wall of the via hole of the flexible circuit board by electroplating And the metal heat conduction layer is in contact with the solder layer; thereby, the solder layer can be quickly and uniformly melted, thereby reducing the time required for the process and enhancing the bonding strength between the rigid circuit board and the flexible circuit board.

Further, in the step of providing a flexible circuit board, a first pad is disposed on a first side of the body of the flexible circuit board, and a second pad is disposed on a second side of the body of the flexible circuit board The via hole is formed by simultaneously penetrating through the body, the first pad and the second pad; and in the hot-melt bonding step, the heat source is located on the outer side of the second pad of the flexible circuit board; further reducing The time required for heat conduction allows the solder layer to be more quickly and uniformly melted.

Further, in the step of disposing a solder layer, the solder layer has a first side and a second side, and the first side of the solder layer is connected to the pad of the hard circuit board, and the second side of the solder layer is Part of the first pad connected to the flexible circuit board; and after the hot-melt bonding step, further comprising a bonding step: the second side of the solder layer is not connected to the first pad of the flexible circuit board And forming a reinforcing portion on a portion of the hard pad of the hard circuit board and the first pad of the flexible circuit board; and the flexible circuit board and the flexible circuit board Firmly joined.

10‧‧‧hard circuit board

11‧‧‧Ontology

12‧‧‧ solder pads

111‧‧‧Hard substrate

112‧‧‧Insulation

113‧‧‧ Conductive layer

20‧‧‧Soft circuit board

21‧‧‧ body

211‧‧‧ first side

212‧‧‧ second side

22‧‧‧First pad

23‧‧‧through holes

213‧‧‧Soft substrate

214‧‧‧Insulation

215‧‧‧First conductive layer

30‧‧‧ solder layer

300‧‧‧ solder

40‧‧‧heat source

10A‧‧‧hard circuit board

12A‧‧‧ pads

20A‧‧‧Soft circuit board

21A‧‧‧ Ontology

212A‧‧‧ second side

213A‧‧‧Soft substrate

214A‧‧‧Insulation

215A‧‧‧First Conductive Layer

216A‧‧‧Second conductive layer

22A‧‧‧First pad

23A‧‧‧through hole

24A‧‧‧second solder pad

30A‧‧‧ solder layer

50A‧‧‧Metal heat conduction layer

10B‧‧‧hard circuit board

12B‧‧‧ solder pads

20B‧‧‧Soft circuit board

22B‧‧‧First pad

23B‧‧‧through hole

30B‧‧‧ solder layer

301B‧‧‧ first side

302B‧‧‧ second side

31B‧‧‧ Strengthening Department

50B‧‧‧heat source

60‧‧‧Soft circuit board

70‧‧‧hard circuit board

80‧‧‧ male fasteners

90‧‧‧Female fasteners

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a flow chart showing the process of the first preferred embodiment of the present invention.

Figure 2 is a side cross-sectional view showing the combination of the first preferred embodiment of the present invention.

3 is a schematic view showing the steps of providing a solder layer in accordance with a first preferred embodiment of the present invention.

Figure 4 is a schematic illustration of a hot melt setting bonding step of a first preferred embodiment of the present invention.

Figure 5 is a flow chart showing the method of the second preferred embodiment of the present invention.

Figure 6 is a side cross-sectional view showing a combination of a second preferred embodiment of the present invention.

Figure 7 is a flow chart showing the method of the third preferred embodiment of the present invention.

Figure 8 is a schematic illustration of a hot melt setting bonding step in accordance with a third preferred embodiment of the present invention.

Figure 9 is a schematic illustration of a step of reinforced bonding in accordance with a third preferred embodiment of the present invention.

Figure 10 is a side cross-sectional view showing a combination of a third preferred embodiment of the present invention.

Figure 11 is a side view of the prior art.

The technical means adopted by the present invention for the purpose of the intended invention are further described below in conjunction with the drawings and preferred embodiments of the invention.

<First Preferred Embodiment>

Referring to FIG. 1 , in the preferred embodiment, the method for fabricating the combination of the flexible circuit board and the rigid circuit board of the present invention comprises the steps of providing a rigid circuit board (S1) and providing a flexible circuit board (S2). a solder layer (S3) and a heat-fusible bonding (S4); the combination obtained by the above-described manufacturing method is as shown in FIG. 2; the steps are detailed as follows: a rigid circuit board 10 is provided (S1) The main body 11 of the rigid circuit board 10 includes a solder substrate 111, an insulating layer 112 and a conductive layer. 113, the conductive layer 113 is disposed on the hard substrate 111, the insulating layer 112 is disposed on the conductive layer 113, and the solder pad 12 is disposed on the conductive layer The conductive layer 113 of the body 11 is electrically connected to the conductive layer 113, and the side edges thereof are in contact with the insulating layer 112.

A flexible circuit board 20 (S2) is provided. As shown in FIG. 3, the body 21 of the flexible circuit board 20 has a first side 211 and a second side 212, and a first side 211 is disposed on the first side 211 of the body 21. a soldering pad 22, and a through hole 23 is formed through the body 21 and the first pad 22; further, the body 21 of the flexible circuit board 20 includes a flexible substrate 213, an insulating layer 214 and a first conductive The first conductive pad 22 is disposed on the first conductive layer 215 of the body 21 and electrically connected to the first conductive layer 215, and the first conductive pads 215 are respectively connected to the first conductive layer 215. Its side edge is in contact with the insulating layer 214.

A solder layer 30 (S3) is disposed: as shown in FIG. 4, a solder layer 30 is formed between the pad 12 of the rigid circuit board 10 and the first pad 22 of the flexible circuit board 20, and the solder layer 30 is formed. The solder layer 30 is applied to the solder pad 12 of the hard circuit board 10 or/and the flexible circuit board 20. The first pad 22 is formed by bonding the pad 12 of the rigid circuit board 10 and the first pad 22 of the flexible circuit board 20 to each other.

Hot-melt bonding (S4): Please refer to FIG. 2 and FIG. 4, a heating source 40 is provided on the second side 212 of the body 21 of the flexible circuit board 20, so that the generated thermal energy is transmitted through the via 23 to make the solder The layer 30 is hot-melted, and then the heat source 40 is removed, and the solder layer 30 is solidified between the solder pad 12 of the rigid circuit board 10 and the first pad 22 of the flexible circuit board 20, and the hard circuit board 10 is The flexible circuit board 20 is connected via the solder layer 30 Hehe.

The combination of the flexible circuit board 20 and the rigid circuit board 10 is formed by the via holes 23, so that thermal energy can pass through the via holes 23 to reach the solder layer 30 between the flexible circuit board 20 and the hard circuit board 10. The solder layer 30 can be melted by absorbing sufficient thermal energy, and then solidified and shaped after the thermal energy is removed, so that the flexible circuit board 20 and the hard circuit board 10 are integrated through the heat-fusible solder layer 30, without using any The additional components also eliminate the purchase and use of the fixtures corresponding to the components, which greatly reduces the cost of the combination of the flexible circuit board 20 and the rigid circuit board 10; at the same time, the thickness of the solder layer 30 is relatively thin, The combined body produced by the above-mentioned manufacturing method does not occupy a space, so that it can be applied to light, thin, short, and small products without being limited by the space size at the application level.

Further, in the preferred embodiment, the solder layer 30 is formed between the pad 12 of the rigid circuit board 10 and the first pad 22 of the flexible circuit board 20, but not limited thereto; In a preferred embodiment, the hard circuit board is not provided with a solder pad, and the first solder pad is not disposed on the body of the flexible circuit board. Further, the solder layer is directly insulated from the conductive layer of the hard circuit board. The layers are connected, and at the same time, the solder layer is directly connected to the first conductive layer and the insulating layer of the flexible circuit board.

<Second preferred embodiment>

Referring to FIG. 5, the combination of the flexible circuit board and the rigid circuit board of the preferred embodiment is further provided between the step of providing a flexible circuit board (S2) and the step of disposing a solder layer (S3). There is a step of forming a metal heat conducting layer (S5).

Please refer to FIG. 6 for providing a flexible circuit board 20A. A second pad 24A is disposed on the second side surface 212A of the body 21A of the flexible circuit board 20A. The via hole 23A is formed through the body 21A, the first pad 22A and the second pad 24A. Further, the body 21A of the flexible circuit board 20A includes a second conductive layer 216A. The first conductive layer 215A and the second conductive layer 216A are respectively disposed on opposite sides of the flexible substrate 213A, and the insulating layer 214A is coated. The flexible substrate 213A, the first conductive layer 215 and the second conductive layer 216 are disposed on the second conductive layer 216A of the body 21A and electrically connected to the second conductive layer 216A, and the side edge and the insulating layer 214A. Docked.

Referring to FIG. 6, in the step of forming a metal heat conductive layer 50A, the metal heat conductive layer 50A is formed on the wall surface of the conductive via 23A of the flexible circuit board 20A by electroplating, and both ends of the metal heat conductive layer 50A are formed. The first bonding pad 22A and the second bonding pad 24A are respectively connected to each other; in the preferred embodiment, the metal thermally conductive layer 50A is made of copper or an alloy thereof.

Referring to FIG. 6, in the step of disposing a solder layer 30A, the solder layer 30A is in contact with the metal heat conductive layer 50A through the first pad 22A.

Referring to FIG. 6, in the hot-melt bonding step, the heating source is located on the outer side of the second pad 24A of the flexible circuit board 20A.

Referring to FIG. 6, in the preferred embodiment, the thermal energy of the heat source can reach the first pad 22A and the solder layer 30A through the second pad 24A and the metal heat conducting layer 50A, so that the solder layer 30A The fuse can be melted relatively quickly and uniformly, thereby reducing the time required for the process, and avoiding the solder layer 30A having a small portion of the heat fusion type due to uneven heating, thereby enhancing the bonding strength between the rigid circuit board 10A and the flexible circuit board 20A. .

<Third preferred embodiment>

Referring to FIG. 7, the combination of the flexible circuit board and the rigid circuit board of the preferred embodiment is further provided with a step of strengthening bonding (S6) after the step of the hot-melt bonding (S4).

Referring to FIG. 8 , in the step of disposing a solder layer 30B, the solder layer 30B is formed by applying solder to the pad 12B of the hard circuit board 10B, or is respectively applied to the hard circuit board 10B. The solder pad 12B and the first pad 22B of the flexible circuit board 20B are formed by bonding the pad 12B of the rigid circuit board 10B and the first pad 22B of the flexible circuit board 20B to each other; the solder layer 30B has a first side surface 301B and a second side surface 302B. The first side surface 301B of the solder layer 30B is in contact with the solder pad 12B of the rigid circuit board 10B, and the second side surface 302B of the solder layer 30B is partially connected thereto. The first pad 22B of the flexible circuit board 20B is connected, that is, the position of the pad 12B of the rigid circuit board 10B is opposite to the position of the first pad 22B of the flexible circuit board 20B.

Referring to FIG. 8 to FIG. 10, in the bonding step, a heat source 50B is used to fuse the second side 302B of the solder layer 30B and the first pad 22B of the flexible circuit board 20B. Forming and forming a reinforcing portion 31B at and around the pad 12B of the rigid circuit board 10B and the first pad 22B of the flexible circuit board 20B, reinforcing the hard circuit board 10B and the flexible circuit Engagement of the plate 20B.

In the preferred embodiment, the bonding strength of the rigid circuit board 10B and the flexible circuit board 20B is strengthened by the forming of the reinforcing portion 31B of the solder layer 30B, so that the rigid circuit board 10B and the flexible circuit board 20B are stabilized. Ground joints.

In summary, the combination of the flexible circuit board and the rigid circuit board of the present invention can be thermally transmitted through the via holes 23, 23A, 23B to the flexible circuit boards 20, 20A, 20B and the hard circuit boards 10, 10A, The solder layers 30, 30A, 30B between 10B cause the solder layers 30, 30A, 30B to be thermally fused and shaped, thus allowing the flexible circuit boards 20, 20A, 20B and the hard circuit boards 10, 10A, 10B to pass through the heat-fusible type. The solder layers 30, 30A, 30B are combined without the use of any additional components and their jigs, thereby reducing the cost of the process, and the thickness of the solder layers 30, 30A, 30B is relatively thin, so that the method of fabrication is The obtained combined body does not occupy space, and has a wider applicability.

The above is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Although the present invention has been disclosed in the above preferred embodiments, it is not intended to limit the present invention, any technology that is familiar with the present invention. A person skilled in the art can make some modifications or modifications to equivalent embodiments by using the above-disclosed technical contents without departing from the technical scope of the present invention. It is still within the scope of the technical solution of the present invention to make any simple modifications, equivalent changes and modifications to the above embodiments.

10‧‧‧hard circuit board

11‧‧‧Ontology

12‧‧‧ solder pads

20‧‧‧Soft circuit board

21‧‧‧ body

211‧‧‧ first side

212‧‧‧ second side

22‧‧‧First pad

23‧‧‧through holes

30‧‧‧ solder layer

Claims (13)

A method for manufacturing a combination of a flexible circuit board and a rigid circuit board, the method comprising: providing a rigid circuit board: the hard circuit board comprises a body, the body of the hard circuit board comprises a conductive layer, and the body of the hard circuit board a conductive pad is disposed on the conductive layer; a flexible circuit board is provided: the flexible circuit board includes a body, and the body of the flexible circuit board has a first side, a second side, and a second side and the second side a first conductive layer between the sides, the first side is provided with a first pad, the first pad is located on the first conductive layer and is electrically connected to the first conductive layer, the first side of the body and the first A via hole is formed between the two sides, and the via hole penetrates through the first pad and the first conductive layer simultaneously; a solder layer is disposed: a solder layer is formed on the body of the hard circuit board and the flexible circuit board Between the first side of the body, and the solder layer is located at the via of the flexible circuit board, and the solder layer is formed between the solder pad of the hard circuit board and the first pad of the flexible circuit board; Fused bonding: providing a heating source at the second side of the body of the flexible circuit board, passing the through hole to fuse the solder layer, and after removing the heating source, the solder layer is solidified and shaped on the body of the rigid circuit board Between the body of the flexible circuit board and the pad of the rigid circuit board and the first pad of the flexible circuit board, the hard circuit board and the flexible circuit board are joined via a solder layer. The method for fabricating the combination of the flexible circuit board and the hard circuit board according to claim 1, in the step of providing a flexible circuit board, on the flexible circuit board a second pad is disposed on the second side of the body, the through hole is simultaneously penetrated through the body, the first pad and the second pad; and in the hot-melt bonding step, the heating source is located on the flexible circuit board The outer side of the second pad. The method for fabricating a combination of a flexible circuit board and a rigid circuit board according to claim 1, wherein between the step of providing a flexible circuit board and the step of providing a solder layer, further comprising the step of forming a metal heat conductive layer: forming by electroplating The metal heat conduction layer is on the wall surface of the via hole of the flexible circuit board, and the metal heat conduction layer is connected to the first pad of the flexible circuit board; in the step of disposing a solder layer, the solder layer is thermally conductive to the metal through the first pad The layers are connected. The method for fabricating a combination of a flexible circuit board and a rigid circuit board according to claim 2, further comprising the step of forming a metal heat conductive layer between the step of providing a flexible circuit board and the step of providing a solder layer: forming by electroplating The metal heat conduction layer is disposed on the wall surface of the via hole of the flexible circuit board, and the two ends of the metal heat conduction layer are respectively connected to the first pad and the second pad; in the step of disposing a solder layer, the solder layer is first through The pad is in contact with the metal heat conducting layer and the second pad. The method of manufacturing a combination of a flexible circuit board and a hard circuit board according to any one of claims 1 to 4, wherein in the step of disposing a solder layer, the solder layer has a first side and a second side, the solder The first side of the layer is connected to the hard circuit board, and the second side of the solder layer is partially connected to the flexible circuit board; after the hot melt bonding step, the step of bonding is further included: the second side of the solder layer The portion that is not in contact with the flexible circuit board is heat-set, and the cladding forms a reinforcing portion at and around the rigid circuit board and the flexible circuit board. A combination of a flexible circuit board and a rigid circuit board, comprising: A rigid circuit board comprising a body, the body of the body comprises a conductive layer, and a conductive pad is disposed on the conductive layer of the body; a flexible circuit board comprising a body and a through hole, the body having a first side a second side and a first conductive layer between the first side and the second side, the first side is provided with a first pad, the first pad is located on the first conductive layer and The first conductive layer is electrically connected, the through hole is formed between the first side surface and the second side surface, and the through hole penetrates through the first pad and the first conductive layer simultaneously; a solder layer is thermally melted Formed between the body of the rigid circuit board and the body of the flexible circuit board, and is heat-fused between the solder pad of the hard circuit board and the first pad of the flexible circuit board, and is located in the flexible circuit At the through hole of the board. The combination of a flexible circuit board and a hard circuit board according to claim 6, wherein a second soldering pad is disposed on the second side of the body of the flexible circuit board, and the through hole is simultaneously formed in the body and the first soldering Pad and second pad. The combination of a flexible circuit board and a hard circuit board according to claim 6, comprising a metal heat conduction layer disposed on a wall surface of the through hole of the flexible circuit board, and the metal heat conduction layer transmits the softness The first pad of the board is connected to the solder layer. The combination of the flexible circuit board and the hard circuit board according to claim 7, comprising a metal heat conduction layer disposed on a wall surface of the conductive hole of the flexible circuit board, and two ends of the metal heat conduction layer When the first solder pad and the second solder pad are respectively connected to each other, the solder layer is in contact with the metal heat conductive layer and the second solder pad through the first solder pad. The combination of a flexible circuit board and a hard circuit board according to any one of claims 6 to 9, wherein the solder layer includes a reinforcing portion, and the reinforcing portion covers the hard circuit board and the flexible circuit board; Around it. The combination of a flexible circuit board and a hard circuit board according to claim 6 or 8, wherein the flexible circuit board body comprises a flexible substrate and an insulating layer, and the two sides of the first conductive layer are respectively separated from the insulating layer and the flexible substrate In connection, the side edges of the first pad are in contact with the insulating layer. The combination of a flexible circuit board and a hard circuit board according to claim 7 or 9, wherein the flexible circuit board body comprises a flexible substrate, an insulating layer and a second conductive layer, the first conductive layer and the second conductive layer. The layers are respectively disposed on opposite sides of the flexible substrate, and the insulating layer covers the flexible substrate, the first conductive layer and the second conductive layer, the side edge of the first pad is in contact with the insulating layer, and the second pad is disposed on the body The second conductive layer is electrically connected to the second conductive layer, and the side edge of the second pad is in contact with the insulating layer. The combination of a flexible circuit board and a hard circuit board according to any one of claims 6 to 9, wherein the body of the rigid circuit board comprises a rigid substrate and an insulating layer, and the conductive layer is disposed on the hard substrate, and the insulating layer The conductive layer is disposed on the conductive layer, and the side edge of the solder pad is in contact with the insulating layer.