CN108601215B

CN108601215B - Rigid-flex board and terminal

Info

Publication number: CN108601215B
Application number: CN201810375912.5A
Authority: CN
Inventors: 曾元清
Original assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Current assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Priority date: 2016-02-25
Filing date: 2016-02-25
Publication date: 2020-01-14
Anticipated expiration: 2036-02-25
Also published as: CN108601215A; CN105704910A; CN105704910B

Abstract

The invention discloses a rigid-flex board and a terminal, wherein the rigid-flex board comprises a base material layer, a rigid circuit substrate, an electronic component and a shielding film, the base material layer comprises a first area, the rigid circuit substrate is attached to the first area, an orthographic projection area of the rigid circuit substrate on the base material layer is overlapped with the first area, the rigid circuit substrate is provided with a shielding area, the electronic component is welded in the shielding area, the shielding film is fixed on the rigid circuit substrate, the shielding film is overlapped with the shielding area in the orthographic projection area of the rigid circuit substrate, and the shielding film is laminated and covers the electronic component. Electronic components in the shielding area are pressed by the shielding film and are stable on the rigid circuit substrate, so that the electronic components are not easy to fall off from the rigid circuit substrate, and the stability of the rigid-flexible printed circuit board is enhanced.

Description

Rigid-flex board and terminal

Technical Field

The invention relates to the field of electronic equipment, in particular to a rigid-flex board and a terminal.

Background

At present, the application of the rigid-flex circuit board is more and more extensive, and most rigid-flex circuit boards are provided with a plurality of electronic elements in a rigid area so as to realize the functions of the printed circuit board. However, at present, most rigid-flex boards are not as rigid as conventional printed circuit boards, so that the load-bearing stress of the rigid-flex boards in the rigid area is not good, and a plurality of electronic components in the rigid area of the rigid-flex boards are easily subjected to the action of vibration stress, so that the electronic components are easily damaged or loosened, and the structural stability of the rigid-flex boards is low.

Disclosure of Invention

In view of this, the present invention provides a rigid-flex board and a terminal, which improve structural stability.

The invention provides a rigid-flexible printed circuit board, which comprises a substrate layer, a rigid circuit substrate, an electronic component and a shielding film, wherein the substrate layer comprises a first area, the rigid circuit substrate is attached to the first area, an orthographic projection area of the rigid circuit substrate on the substrate layer is overlapped with the first area, the rigid circuit substrate is provided with a shielding area, the electronic component is welded in the shielding area, the shielding film is fixed on the rigid circuit substrate, the orthographic projection area of the shielding film on the rigid circuit substrate is overlapped with the shielding area, and the shielding film is laminated and covers the electronic component.

The electronic assembly comprises a plurality of first electronic elements and a second electronic element, wherein the internal stress of the plurality of first electronic elements is larger than the internal stress of the second electronic element, and the first electronic elements are arranged around the second electronic element.

The rigid-flex circuit board comprises two rigid circuit substrates, namely a first rigid circuit substrate and a second rigid circuit substrate, wherein the first rigid circuit substrate and the second rigid circuit substrate are respectively attached to two sides of the base material layer.

The electronic assembly comprises a third electronic element and a fourth electronic element, wherein the internal stress of the third electronic element is greater than the internal stress of the fourth electronic element, the third electronic element is welded on the first rigid circuit substrate, and the fourth electronic element is welded on the second rigid circuit substrate and is located at a position opposite to the third electronic element.

The hard circuit substrate comprises a hard insulating layer, a circuit layer and a welding-proof ink layer, wherein the hard insulating layer is attached to the first area, an orthographic projection area on the substrate layer is overlapped with the first area, the circuit layer is attached to the hard insulating layer and is positioned on one side of the substrate layer opposite to the first area, the welding-proof ink layer is coated on the circuit layer to cover the circuit layer, and the electronic component penetrates through the welding-proof ink layer and is welded on the circuit layer.

The substrate layer further comprises a second area connected to the edge of the first area, the rigid-flexible printed circuit board further comprises a copper foil layer, and the copper foil layer is arranged in the first area and the second area and stacked between the substrate layer and the rigid circuit substrate.

The flexible-rigid combined board comprises two copper foil layers, namely a first copper foil layer and a second copper foil layer, wherein the first copper foil layer and the second copper foil layer are respectively stacked on two sides of the base material layer, the first copper foil layer is provided with a through hole penetrating to the second copper foil layer, and a conductor connected with the first copper foil layer and the second copper foil layer is arranged in the through hole.

The rigid-flex board further comprises a first cover film and a second cover film, wherein the first cover film is attached to the first copper foil layer, the second cover film is attached to the second copper foil layer, and the orthographic projection area of the first cover film and the orthographic projection area of the second cover film on the base material layer are overlapped with the second area.

The first copper foil layer is provided with a grounding wire, the second copper foil layer is provided with a signal wire, and the electric conductor is connected with the signal wire and the grounding wire.

The invention also provides a terminal, wherein the terminal comprises a body, a main board arranged in the body and any one of the rigid-flex boards, and the rigid-flex board is arranged in the body and electrically connected with the main board.

According to the rigid-flex board and the terminal, the electronic component is welded in the shielding area, the shielding film is utilized to press and cover the electronic component, and the orthographic projection area of the shielding film on the rigid circuit substrate is overlapped with the shielding area, so that the electronic component in the shielding area is firmly fixed on the rigid circuit substrate by the pressing force of the shielding film, and the electronic component is not easy to fall off from the rigid circuit substrate, and the stability of the rigid-flex board is enhanced.

Drawings

In order to more clearly illustrate the technical solution of the present invention, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic cross-sectional view of a rigid-flex board provided by the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

Referring to fig. 1, the rigid-flex board 100 provided by the present invention includes a substrate layer 10, a rigid circuit board 20, an electronic component and a shielding film 40, where the substrate layer 10 includes a first region 10a, the rigid circuit board 20 is correspondingly attached to the first region 10a, the rigid circuit board 20 is provided with a shielding region 20a, the electronic component is welded in the shielding region 20a of the rigid circuit board 20 and is concentrated at a geometric center of the shielding region 20a, the shielding film 40 is fixed on the rigid circuit board 20 and is pressed on and covers the electronic component, and the shielding film 40 is overlapped with the shielding region in a forward projection area of the rigid circuit board 20.

By welding the electronic component in the shielding area 20a, the shielding film 40 is pressed and covers the electronic component, and the orthographic projection area of the shielding film 40 on the rigid circuit substrate 20 coincides with the shielding area, so that the electronic component in the shielding area 20a is firmly fixed on the rigid circuit substrate 20 by the pressing force of the shielding film 40, and the electronic component is not easily detached from the rigid circuit substrate 20, thereby enhancing the stability of the rigid-flex printed circuit board 100.

In this embodiment, the substrate layer 10 may adopt materials such as polyimide or Polyethylene terephthalate (PET), so that the copper foil line is disposed on the substrate layer 10, and the substrate layer 10 may provide an insulating environment for the copper foil line. Preferably, the thickness of the substrate layer 10 may be 20 μm. Substrate layer 10 can set up first district 10a and second district 10b, second district 10b is used for presenting the flexibility, and is convenient soft combining board 100 produces deformation, and then convenient external device is connected to soft or hard combining board 100, first district 10a is fixed hard circuit base plate 20, thereby improves soft combining board 100's rigidity utilizes hard circuit base plate 20 is last fixed electronic component, and utilizes hard circuit base plate 20's hardness, thereby it is convenient soft combining board 100 assembles in the terminal.

In this embodiment, the hard circuit board 20 is formed by a hard circuit board manufacturing process, the hard circuit board 20 carries the electronic component, and the hard circuit board 20 has a signal circuit electrically connected to the electronic component, so as to provide an electrical signal to the electronic component, and enable the electronic component to operate. Specifically, the hard circuit board 20 is in a plate shape, the hard circuit board 20 is bonded to the first region 10a of the substrate layer 10, and the hard circuit layer 20 is welded to the electronic component on the side away from the substrate layer 10 and is bonded to the shielding film 40. The geometric center of the shielding region 20a of the rigid wiring substrate 20 coincides with the geometric center of the first region 10a, and the periphery of the shielding region 20a is disposed at equal intervals to the periphery of the first region 10 a. So that the stress of the electronic component in the shielding region 20a on the hard line layer 20 is concentrated around the geometric center of the first region 10a, so that the hard line layer 20 can effectively support the electronic component.

In this embodiment, the electronic component is composed of a plurality of electronic components, and the electronic components may be capacitors, resistors, diodes, or transistors. The electronic components are connected to the hard circuit board 20 through a circuit, so that the rigid-flex board 100 provides a circuit structure, and the rigid-flex board 100 is applied to a terminal, so that the rigid-flex board 100 can implement electronic information processing. The electronic component is soldered on the rigid circuit board 20, and the electronic component is supported by the rigid circuit board 20, so that the electronic component has soldering stress on the rigid circuit board 20, and when a soldering gap occurs between the electronic component and the rigid circuit board 20, the electronic component is easily led to fall off, and thus the electronic component is more stable on the rigid circuit board 20 under the pressing effect of the shielding film 40.

In this embodiment, the periphery of the shielding film 40 may be a periphery adhered to the shielding region 20a, and the shielding film 40 electromagnetically shields the electronic component, so as to protect the electronic component and prevent the electronic component from receiving electromagnetic interference, thereby improving the interference prevention performance of the rigid-flex board 100, so that the rigid-flex board 100 may be applied to a scene with a severe electromagnetic environment. In other embodiments, the peripheral edge of the shielding film 40 may also be welded to the peripheral edge of the shielding region 20 a.

Further, the electronic assembly comprises a plurality of first electronic elements 31 and a second electronic element 32, wherein the internal stress of the plurality of first electronic elements 31 is greater than the internal stress of the second electronic element 32, and the first electronic elements 31 are arranged around the second electronic element 32.

In this embodiment, the first electronic component 31 may be a resistor, the second electronic component 32 may be a capacitor, and obviously, the internal stress of the resistor is greater than the internal stress of the capacitor, that is, the strength of the resistor is greater than that of the capacitor, so that the first electronic component 31 is more stable on the hard circuit substrate 20 than the second electronic component 32. The first electronic element 31 is arranged around the second electronic element 32, so that the first electronic element 31 reinforces the stability of the rigid circuit board 20 around the second electronic element 32, the rigid circuit board 20 around the second electronic element 32 is not easy to deform, and the second electronic element 32 is stable, so that the whole structure of the rigid-flex board 100 is stable. In other embodiments, the first electronic component 31 may also be an electronic chip, and the second electronic component 32 may also be a diode.

Further, the rigid-flex circuit board 100 includes two rigid circuit boards 20, which are a first rigid circuit board 21 and a second rigid circuit board 22, and the first rigid circuit board 21 and the second rigid circuit board 22 are respectively attached to two sides of the substrate layer 10. The circuit of the first rigid circuit substrate 21 and the circuit of the second rigid circuit substrate 22 may be different, so that the rigid-flex circuit 100 may have a variety of different circuit structures, and the rigid-flex circuit 100 may be diversified and may be matched with a variety of different terminals. The electronic component may be soldered to only the first rigid circuit board 21, may be soldered to only the second rigid circuit board 22, may be provided with two electronic components soldered to the first rigid circuit board 21 and the second rigid circuit board 22, or may be soldered to both the first rigid circuit board 21 and the second rigid circuit board 22. In another embodiment, if two layers of the base material layer 10 are laminated on the rigid-flex board 100, three groups of the rigid wiring boards 20 may be provided on the rigid-flex board 100.

Further, the electronic assembly includes a third electronic component 33 and a fourth electronic component 34, the internal stress of the third electronic component 33 is greater than the internal stress of the fourth electronic component 34, the third electronic component 33 is soldered on the first rigid wiring substrate 21, and the fourth electronic component 34 is soldered on the second rigid wiring substrate 22 and located opposite to the third electronic component 33.

In this embodiment, the third electronic component 33 may be a chip, the fourth electronic component 34 may be a capacitor, and obviously, the internal stress of the chip is greater than the internal stress of the capacitor, that is, the strength of the chip is greater than that of the capacitor, so that the bonding strength between the third electronic component 33 and the first rigid wiring substrate 21 is greater than that between the fourth electronic component 34 and the second rigid wiring substrate 22. By arranging the fourth electronic element 34 opposite to the third electronic element 33, the third electronic element 33 supports the fourth electronic element 34, so that the fourth electronic element 34 is more firmly fixed on the second rigid circuit board 22, and the overall structure of the rigid-flex circuit 100 is stable. In another embodiment, a plurality of the fourth electronic elements 34 may be disposed at positions facing the third electronic element 33, that is, a plurality of the fourth electronic elements 34 may be disposed in the orthographic projection area of the base material layer 10 and in the orthographic projection area of the third electronic element 33 on the base material layer 33.

Further, the rigid wiring board 20 includes a hard insulating layer 201, a wiring layer 202, and a solder resist ink layer 203, and the hard insulating layer 201 is attached to the first region 10a, and an orthogonal projection area on the base material layer 10 coincides with the first region 10 a. The circuit layer 202 is attached to the hard insulating layer 201 and located on the side opposite to the substrate layer 10, the welding-resistant ink layer 203 is coated on the circuit layer 202 to cover the circuit layer 202, and the electronic component 20 penetrates through the welding-resistant ink layer 203 and is welded on the circuit layer 202. Specifically, the hard insulating layer 201 is made of polyethylene, and the hard insulating layer 201 has insulating properties, so that the circuit layer is etched on the hard insulating dirt collection scale 201. By using the hardness of the hard insulating layer 201, the strength of the rigid-flex board 100 on the first area 10a is increased, so that the rigid-flex board 100 is not easily bent in the first area 10 a. The circuit layer 202 may be a copper foil formed by an etching process. The circuit layer 202 may be provided with signal traces or ground traces. The solder resist ink layer 203 protects the lines on the line layer 202 and prevents the lines on the line layer 202 from being short-circuited. The solder mask ink layer 203 is provided with solder holes, and solder is arranged in the solder holes to solder the electronic components to the circuit layer 202.

Further, the substrate layer 10 further includes a second region 10b connected to the edge of the first region 10a, and the rigid-flex board 100 further includes a copper foil layer 50, where the copper foil layer 50 is stacked between the rigid circuit layer group 20 and the substrate layer 10 and is disposed on the first region 10a and the second region 10 b.

In this embodiment, the copper foil layer 50 is a plate with a copper foil disposed on a film, and both the ground trace and the signal trace on the copper foil layer 50 are formed by etching a copper foil according to a predetermined wiring structure. The grounding trace and the signal trace on the copper foil layer 50 may be integrally disposed, the signal trace on the copper foil layer 50 realizes electric conduction between electrical components, and the grounding trace on the copper foil layer 50 performs grounding. Set up copper foil layer 50 on the substrate layer 100 for soft or hard combination board 100 circuit structure is diversified, and utilizes copper foil layer 50 can be along with the second district 10b of substrate layer 10 bends, thereby makes things convenient for the functional unit at soft or hard combination board 100 connection terminal shows the flexible line way board characteristic.

Further, the rigid-flex board 100 includes two layers of the copper foil layer 50, namely a first copper foil layer 51 and a second copper foil layer 52, the first copper foil layer 51 and the second copper foil layer 52 are respectively laminated on two sides of the substrate layer 10, the first copper foil layer 51 is provided with a through hole 53 penetrating through the second copper foil layer 52, and a conductor 54 connecting the first copper foil layer 51 and the second copper foil layer 52 is arranged in the through hole 53.

In this embodiment, the first copper foil layer 51 and the second copper foil layer 52 are respectively provided with different circuits, so as to increase a circuit layout space of the rigid-flex board 100 and improve the conductivity of the rigid-flex board 100. The through hole 53 is opened at one end of the first copper foil layer 51 and extends toward the second copper foil layer 52. Specifically, the through hole 52 further penetrates through the substrate layer 10, and the conductor 54 is a copper pillar penetrating through the through hole 52. The conductor 54 realizes the conduction between the first copper foil layer 51 and the second copper foil layer 52, thereby ensuring the multi-circuit routing requirement of the rigid-flex board 100. The through holes 53 are opened in the second region 10b of the copper foil layer 50 relative to the substrate layer 10, so that the stress of the copper foil layer 50 in the second region 10b is reduced, the strength of the rigid-flexible board 100 in the second region 10b is weakened, and the flexibility of the rigid-flexible board 100 in the second region 10b is improved. In other embodiments, the number of the through holes 53 may be plural, and the conductive body 54 may be configured to be conductive to ground or conductive to signal.

Further, the rigid-flex board 100 further includes a first cover film 61 and a second cover film 62, which are respectively a first cover film 61 attached to the first copper foil layer 51 and a second cover film 62 attached to the second copper foil layer 52, and orthographic projection areas of the first cover film 61 and the second cover film 62 on the substrate layer 10 are overlapped with the second area 10 b.

In this embodiment, the first cover film 61 may be formed by hot press molding using a polyester material. The first cover film 61 is adhered to the first copper foil layer 51 by an adhesive. Specifically, first cover membrane 61 laminate completely in on the first copper foil layer 51 to the part covers signal on the first copper foil layer 51 is walked and is walked with ground connection and walk the line, promptly first cover membrane 61 with the second district 10b of substrate layer 10 is corresponding, in order to protect signal is walked ground connection and is walked and not receive the discount and lose or damage on the first copper foil layer 51, simultaneously, adopts the mode that the viscose pasted, also can make first cover membrane 61 with first copper foil layer 51's connection is inseparabler, prevents first cover membrane 61 shifts and can't be to exposing first cover membrane 61's part is walked and is protected. The second cover film 62 is identical in structure to the first cover film 61, and is not described herein again.

Furthermore, the first copper foil layer 51 is provided with a ground trace (not shown), the second copper foil layer 52 is provided with a signal trace (not shown), and the conductive body 54 is connected to the ground trace of the first copper foil layer 51 and the signal trace of the second copper foil layer 52.

In this embodiment, only the grounding trace is disposed on the first copper foil layer 51, that is, the first copper foil layer 51 is a common electrode. The signal traces on the second copper foil layer 52 realize circuit arrangement, the electric conductor 54 is connected to the ground traces and the signal traces, and the electric conductor 54 provides a ground electrode for the circuit on the second copper foil layer 52, so as to increase the use function of the rigid-flex board 100. In other embodiments, the second copper foil layer 52 may be provided with a ground trace, the first copper foil layer 51 is provided with a signal trace, and the electrical conductor 54 provides a ground electrode for the first copper foil layer 51.

The present invention further provides a terminal (not shown) including a main body (not shown), a main board (not shown) disposed inside the main body, and the rigid-flex board 100, wherein the rigid-flex board 100 is disposed inside the main body and electrically connected to the main board. The terminal can be a mobile phone, a computer, a tablet, a handheld game console or a media player and the like.

According to the rigid-flex board and the terminal, the steel reinforcement is fixed on one side, away from the copper foil layer, of the cover film and close to the hollow window on the cover film, and meanwhile, the grounding conductor is connected between the copper foil layer and the steel reinforcement through the hollow window, so that the steel reinforcement is connected with the copper foil layer, the steel reinforcement is grounded, and the grounding performance of the rigid-flex board is improved.

The foregoing is a preferred embodiment of the present invention, and it should be noted that it would be apparent to those skilled in the art that various modifications and enhancements can be made without departing from the principles of the invention, and such modifications and enhancements are also considered to be within the scope of the invention.

Claims

1. The rigid-flex board is characterized by comprising a base material layer, a rigid circuit substrate, an electronic component and a shielding film, wherein the base material layer comprises a first area, the rigid circuit substrate is attached to the first area, an orthographic projection area of the rigid circuit substrate on the base material layer coincides with the first area, the rigid circuit substrate is provided with a shielding area, the electronic component is welded in the shielding area, the shielding film is fixed on the rigid circuit substrate, an orthographic projection area of the rigid circuit substrate coincides with the shielding area, the shielding film is laminated and covers the electronic component, the rigid circuit substrate comprises a rigid insulating layer, a circuit layer and an anti-welding ink layer, the rigid insulating layer is attached to the first area, and the orthographic projection area on the base material layer coincides with the first area, the circuit layer laminate in on the stereoplasm insulating layer, and be located with substrate layer mutually carries on the back one side mutually, prevent welding printing ink layer coat in on the circuit layer, cover the circuit layer, electronic component passes prevent welding printing ink layer, weld in on the circuit layer, the holding recess has been seted up to the lower surface of barrier film, prevent welding printing ink layer be formed with the holding clearance that the holding recess set up relatively and communicate, the holding clearance with the holding recess forms the accommodation space jointly, the shape and the size of accommodation space with electronic component matches, electronic component wears to establish the accommodation clearance and the card is established in the accommodation recess.

2. The board according to claim 1, wherein the electronic components include a plurality of first electronic components and a second electronic component, each of the first electronic components has an internal stress greater than an internal stress of the second electronic component, and the first electronic components are arranged around the second electronic component.

3. The rigid-flex board according to claim 1 or 2, wherein the rigid-flex board comprises two rigid circuit substrates, namely a first rigid circuit substrate and a second rigid circuit substrate, and the first rigid circuit substrate and the second rigid circuit substrate are respectively attached to two opposite sides of the base material layer.

4. The board according to claim 3, wherein the electronic components include a third electronic component and a fourth electronic component, the internal stress of the third electronic component is greater than the internal stress of the fourth electronic component, the third electronic component is soldered on the first rigid wiring substrate, and the fourth electronic component is soldered on the second rigid wiring substrate and located opposite to the third electronic component.

5. The board of claim 1, wherein the substrate layer further includes a second region connected to the first region, and the board further includes a copper foil layer disposed between the first region and the second region and stacked between the substrate layer and the hard circuit substrate.

6. The board of claim 5, wherein the board comprises two copper foil layers, namely a first copper foil layer and a second copper foil layer, the first copper foil layer and the second copper foil layer are respectively stacked on two opposite sides of the substrate layer, the first copper foil layer is provided with a through hole penetrating to the second copper foil layer, and a conductor connecting the first copper foil layer and the second copper foil layer is arranged in the through hole.

7. The board according to claim 6, further comprising a first cover film and a second cover film, wherein the first cover film is attached to the first copper foil layer and the second cover film is attached to the second copper foil layer, and the orthographic projection areas of the first cover film and the second cover film on the substrate layer coincide with the second areas.

8. The board according to claim 6, wherein the first copper foil layer is provided with a ground trace, the second copper foil layer is provided with a signal trace, and the electrical conductor is connected to the signal trace and the ground trace.

9. A terminal, comprising a body, a main board disposed inside the body, and the rigid-flex board according to any one of claims 1 to 8, wherein the rigid-flex board is disposed inside the body and electrically connected to the main board.