CN111491442A

CN111491442A - Circuit board with electromagnetic shielding structure and manufacturing method thereof

Info

Publication number: CN111491442A
Application number: CN202010364350.1A
Authority: CN
Inventors: 张立国
Original assignee: Wuhan Excel Science And Technology Ltd
Current assignee: Wuhan Excel Science And Technology Ltd
Priority date: 2020-04-30
Filing date: 2020-04-30
Publication date: 2020-08-04
Anticipated expiration: 2040-04-30
Also published as: CN111491442B

Abstract

The invention relates to the field of printed circuit boards, in particular to a circuit board with an electromagnetic shielding structure and a manufacturing method thereof, wherein the circuit board comprises a middle circuit board layer, an upper metal shielding layer and a lower metal shielding layer, interlayer electric insulation layers are respectively arranged between the middle circuit board layer and the upper and lower metal shielding layers, and a conductive circuit is arranged in the middle circuit board layer; the upper and lower metal shielding layers are electrically communicated through the side closed-loop shielding enclosure wall, and the conducting circuit is enclosed in the side closed-loop shielding enclosure wall; the side closed-loop shielding wall is formed by electroplating or filling conductive materials in closed-loop blind grooves which are connected end to end. According to the invention, the closed-loop shielding wall with the side faces is formed by electroplating or filling the conductive materials in the closed-loop blind grooves which are connected end to end, so that a good side shielding effect can be realized, the closed-loop shielding wall with the side faces is electrically connected with the upper and lower metal shielding layers to form an electromagnetic shielding structure of a continuous closed space, and a perfect electromagnetic shielding effect can be formed on a middle conductive circuit.

Description

Circuit board with electromagnetic shielding structure and manufacturing method thereof

Technical Field

The invention relates to the field of printed circuit boards, in particular to a circuit board with an electromagnetic shielding structure and a manufacturing method thereof.

Background

Along with the continuous improvement of signal frequency, the electromagnetic radiation of the circuit board is larger and larger, and the circuit board can be coupled to other electrical appliances to cause serious signal interference in serious cases; there are some high frequency signals, and to avoid electromagnetic interference in the environment of the electrical appliance, good electromagnetic shielding is needed to protect the internal conductive signal circuit from external electromagnetic interference, so it is necessary to design the electromagnetic shielding for the circuit board carrying the high frequency signals.

The existing electromagnetic shielding of the circuit board usually adopts the following steps: electromagnetic shielding is performed on the upper surface and the lower surface of the circuit board, so that the electromagnetic shielding on the side surface of the circuit board is usually neglected, and the side surface shielding effect is not good even if the electromagnetic shielding on the side surface is available.

Disclosure of Invention

The technical problem to be solved by the invention is to provide a circuit board with an electromagnetic shielding structure and a manufacturing method thereof, which can better solve the problem of electromagnetic shielding on the side surface of the circuit board and can realize perfect electromagnetic shielding effect.

The technical scheme for solving the technical problems is as follows:

in a first aspect, the present invention provides a circuit board having an electromagnetic shielding structure, the circuit board including: the circuit board comprises a middle circuit board layer, an upper metal shielding layer and a lower metal shielding layer, wherein the upper metal shielding layer and the lower metal shielding layer are correspondingly covered on the upper surface and the lower surface of the middle circuit board layer;

the upper metal shielding layer and the lower metal shielding layer are electrically communicated through a side closed-loop shielding enclosure wall embedded between the upper metal shielding layer and the lower metal shielding layer, and a conducting circuit in the middle circuit board layer is enclosed in the side closed-loop shielding enclosure wall;

the side closed-loop shielding wall is formed by electroplating or filling conductive materials in closed-loop blind grooves which are connected end to end;

the upper metal shielding layer, the side closed-loop shielding enclosure wall and the lower metal shielding layer jointly form an electromagnetic shielding structure of the conducting circuit in the middle circuit board layer.

In a second aspect, the invention provides a method for manufacturing a circuit board with an electromagnetic shielding structure, wherein the circuit board manufactured by the method comprises a middle circuit board layer, and an upper metal shielding layer and a lower metal shielding layer which are correspondingly covered on the upper surface and the lower surface of the middle circuit board layer, wherein interlayer electric insulation layers are respectively arranged between the middle circuit board layer and the upper metal shielding layer as well as between the middle circuit board layer and the lower metal shielding layer; the middle circuit board layer is internally provided with a conductive circuit;

the manufacturing method comprises the following steps of,

processing closed-loop blind grooves which are connected end to end and surround the conducting circuit between the upper metal shielding layer and the lower metal shielding layer by adopting laser;

electroplating or filling a conductive material in the closed-loop blind groove to form a side closed-loop shielding enclosure wall for electrically communicating the upper metal shielding layer with the lower metal shielding layer;

The invention has the beneficial effects that: according to the circuit board with the electromagnetic shielding structure and the manufacturing method thereof, the closed-loop blind grooves which are connected end to end are electroplated or filled with the conductive materials to form the side closed-loop shielding wall, so that a good side shielding effect can be realized, the side closed-loop shielding wall is electrically connected with the upper layer metal shielding layer and the lower layer metal shielding layer to form the electromagnetic shielding structure of a continuous closed space, a very perfect electromagnetic shielding effect can be formed on the middle conductive circuit, and the circuit board electromagnetic shielding structure is a final solution for circuit board electromagnetic shielding.

Drawings

FIG. 1 is a first sectional view of a wiring board according to example 1;

FIG. 2 is a second sectional view of a wiring board according to example 1;

FIG. 3 is a third sectional view of a wiring board in example 1;

fig. 4 is a fourth cross-sectional view of a wiring board in example 1;

FIG. 5 is a first sectional view of a wiring board in example 2;

FIG. 6 is a second sectional view of a wiring board in example 2;

FIG. 7 is a third sectional view of a wiring board in example 2;

FIG. 8 is a first sectional view of a wiring board according to example 3;

FIG. 9 is a second sectional view of a wiring board according to example 3;

FIG. 10 is a third sectional view of a wiring board according to embodiment 3;

FIG. 11 is a schematic structural view of an intermediate circuit board layer;

FIG. 12 is a top or bottom view of the wiring board;

FIG. 13 is a first flowchart of the manufacturing method of example 1 of the present invention;

FIG. 14 is a first flowchart of the manufacturing method of example 2 of the present invention;

FIG. 15 is a second flowchart of the manufacturing method of example 1 of the present invention;

FIG. 16 is a second flowchart of the manufacturing method of example 2 of the present invention;

FIG. 17 is a flowchart illustrating the manufacturing process of example 3 in the manufacturing method of the present invention.

In the drawings, the components represented by the respective reference numerals are listed below:

1. middle circuit plate layer, 2, upper metal shielding layer, 3, lower floor's metal shielding layer, 4, interlayer electrical insulation layer, 5, conducting wire, 6, closed loop blind groove, 7, middle closed loop metal shielding layer.

Detailed Description

The principles and features of this invention are described below in conjunction with the following drawings, which are set forth by way of illustration only and are not intended to limit the scope of the invention.

Example 1:

as shown in fig. 1 and 2 and 12: a circuit board with an electromagnetic shielding structure comprises a middle circuit board layer 1, an upper metal shielding layer 2 and a lower metal shielding layer 3, wherein the upper metal shielding layer 2 and the lower metal shielding layer 3 are correspondingly covered on the upper surface and the lower surface of the middle circuit board layer 1; the upper metal shielding layer 2 and the lower metal shielding layer 3 are electrically communicated through a side closed-loop shielding enclosure wall embedded between the upper metal shielding layer 2 and the lower metal shielding layer 3, and the conducting circuit 5 in the middle circuit board layer 1 is enclosed in the side closed-loop shielding enclosure wall; the side closed-loop shielding wall is formed by electroplating or filling conductive materials in closed-loop blind grooves 6 which are connected end to end; the upper metal shielding layer 2, the side closed-loop shielding enclosure wall and the lower metal shielding layer 3 jointly form an electromagnetic shielding structure of the conducting circuit 5 in the middle circuit board layer 1.

Example 11:

on the basis of embodiment 1, as shown in fig. 1, the closed-loop blind grooves 6 are arranged on the upper metal shielding layer 2 in an end-to-end manner, and the closed-loop blind grooves 6 sequentially penetrate through the interlayer electric insulation layer 4 between the upper metal shielding layer 2 and the middle circuit board layer 1, the non-conductive circuit area of the middle circuit board layer 1 and the interlayer electric insulation layer 4 between the middle circuit board layer 1 and the lower metal shielding layer 3, and end at the lower metal shielding layer 3, the groove bottom of the closed-loop blind grooves 6 is the lower metal shielding layer 3, and the closed-loop blind grooves 6 are internally plated or filled with conductive materials to form the side closed-loop shielding enclosure.

Example 12:

on the basis of embodiment 1, as shown in fig. 2, the closed-loop blind grooves 6 connected end to end are arranged on the lower metal shielding layer 3, and the closed-loop blind grooves 6 sequentially penetrate through the lower metal shielding layer 3 and the interlayer electric insulation layer 4 between the intermediate circuit board layers 1, the non-conductive circuit area of the intermediate circuit board layers 1 and the interlayer electric insulation layer 4 between the intermediate circuit board layers 1 and the upper metal shielding layer 2, and are stopped at the upper metal shielding layer 2, the groove bottom of the closed-loop blind grooves 6 is the upper metal shielding layer 2, and the closed-loop blind grooves 6 are internally plated or filled with conductive materials to form the side closed-loop shielding enclosure.

Example 2:

as shown in fig. 3, 4 and 12: a circuit board with an electromagnetic shielding structure comprises a middle circuit board layer 1, and an upper metal shielding layer 2 and a lower metal shielding layer 3 which are correspondingly covered on the upper surface and the lower surface of the middle circuit board layer 1, wherein interlayer electric insulating layers 4 are respectively arranged between the middle circuit board layer 1 and the upper metal shielding layer 2 and between the middle circuit board layer 1 and the lower metal shielding layer 3, and a conducting circuit 5 is arranged in the middle circuit board layer 1; the upper metal shielding layer 2 and the lower metal shielding layer 3 are electrically communicated through a side closed-loop shielding enclosure wall embedded between the upper metal shielding layer 2 and the lower metal shielding layer 3, and the conducting circuit 5 in the middle circuit board layer 1 is enclosed in the side closed-loop shielding enclosure wall; the side closed-loop shielding wall is formed by electroplating or filling conductive materials in closed-loop blind grooves 6 which are connected end to end.

It is preferred upper metal shielding layer 2 with it is range upon range of to be equipped with the multilayer between the lower floor's metal shielding layer 3 intermediate line sheet layer 1, upper metal shielding layer 2 is adjacent rather than (it represents upper metal shielding layer 2) be equipped with between the intermediate line sheet layer 1 electric insulating layer 4 between the layer, lower floor's metal shielding layer 3 is adjacent rather than (it represents lower metal shielding layer 3) be equipped with between the intermediate line sheet layer 1 electric insulating layer 4 between the layer, every adjacent two-layer all be equipped with between the intermediate line sheet layer 1 electric insulating layer 4 between the layer, at each layer all be equipped with on the intermediate line sheet layer 1 conducting wire 5.

Example 21:

on the basis of embodiment 2, as shown in fig. 3, the closed-loop blind grooves 6 connected end to end are formed in the upper metal shielding layer 2, the closed-loop blind grooves 6 penetrate through all the interlayer electrical insulation layers 4 and all the non-conducting circuit regions of the intermediate circuit board layer 1 and end at the lower metal shielding layer 3, the bottom of the closed-loop blind grooves 6 is the lower metal shielding layer 3, and a conductive material is plated or filled in the closed-loop blind grooves 6 to form the side closed-loop shielding enclosure wall; the conducting wires 5 in all the middle circuit board layers 1 are enclosed in the side closed-loop shielding enclosing wall; the upper metal shielding layer 2, the side closed-loop shielding enclosure wall and the lower metal shielding layer 3 jointly form an electromagnetic shielding structure of the conducting wires 5 in the middle circuit board layer 1.

Example 22:

on the basis of embodiment 2, as shown in fig. 4, the lower metal shielding layer 3 is provided with closed-loop blind grooves 6 connected end to end, the closed-loop blind grooves 6 penetrate through all the interlayer electrical insulation layers 4 and all the non-conducting circuit regions of the intermediate circuit board layer 1 and end at the upper metal shielding layer 2, the bottom of the closed-loop blind grooves 6 is the upper metal shielding layer 2, and the closed-loop blind grooves 6 are plated or filled with a conductive material to form the side closed-loop shielding enclosure wall; the conducting wires 5 in all the middle circuit board layers 1 are enclosed in the side closed-loop shielding enclosing wall; the upper metal shielding layer 2, the side closed-loop shielding enclosure wall and the lower metal shielding layer 3 jointly form an electromagnetic shielding structure of the conducting wires 5 in the middle circuit board layer 1.

Example 3:

as shown in fig. 5, 6, 7 and 12: a circuit board with an electromagnetic shielding structure comprises a middle circuit board layer 1, and an upper metal shielding layer 2 and a lower metal shielding layer 3 which are correspondingly covered on the upper surface and the lower surface of the middle circuit board layer 1, wherein interlayer electric insulating layers 4 are respectively arranged between the middle circuit board layer 1 and the upper metal shielding layer 2 and between the middle circuit board layer 1 and the lower metal shielding layer 3, and a conducting circuit 5 is arranged in the middle circuit board layer 1; the upper metal shielding layer 2 and the lower metal shielding layer 3 are electrically communicated through a side closed-loop shielding enclosure wall embedded between the upper metal shielding layer 2 and the lower metal shielding layer 3, and the conducting circuit 5 in the middle circuit board layer 1 is enclosed in the side closed-loop shielding enclosure wall; the side closed-loop shielding wall is formed by electroplating or filling conductive materials in closed-loop blind grooves 6 which are connected end to end.

Preferably, an intermediate closed-loop metal shielding layer 7 with a preset width is embedded in the intermediate circuit board layer 1 and around the conductive circuit 5; the upper metal shielding layer 2, the lower metal shielding layer 3 and the middle closed-loop metal shielding layer 7 in the middle circuit board layer 1 are electrically communicated through a side closed-loop shielding fence embedded between the upper metal shielding layer 2 and the lower metal shielding layer 3; the upper metal shielding layer 2, the side closed-loop shielding enclosure, the middle closed-loop metal shielding layer 7 and the lower metal shielding layer 3 jointly form an electromagnetic shielding structure of the conducting circuit 5 in the middle circuit board layer 1.

Example 31:

on the basis of embodiment 3, as shown in fig. 5, the side closed-loop shielding enclosure wall is of an upper and lower split structure and is electrically connected through the intermediate closed-loop metal shielding layer 1; the upper metal shielding layer 2 is provided with closed-loop blind grooves 6 connected end to end, the closed-loop blind grooves 6 on the upper metal shielding layer 2 penetrate through the interlayer electric insulation layer 4 between the upper metal shielding layer 2 and the middle circuit board layer 1 and are stopped at the middle closed-loop metal shielding layer 7, the bottom of the closed-loop blind grooves 6 on the upper metal shielding layer 2 is the middle closed-loop metal shielding layer 7, and the closed-loop blind grooves 6 on the upper metal shielding layer 2 are plated or filled with conductive materials to form side closed-loop enclosure shielding between the middle closed-loop metal shielding layer 7 and the upper metal shielding layer 2 in the middle circuit board layer 1; or/and, be equipped with end to end's closed loop blind groove 6 on lower floor's metal shielding layer 3, and be located on lower floor's metal shielding layer 3 closed loop blind groove 6 runs through lower floor's metal shielding layer 3 with interlaminar electrical insulation layer 4 between intermediate circuit sheet layer 1, and end in intermediate closed loop metal shielding layer 7 is located on lower floor's metal shielding layer 3 the tank bottom of closed loop blind groove 6 does intermediate closed loop metal shielding layer 7 is located on lower floor's metal shielding layer 3 closed loop blind groove 6 internal plating or packing have conducting material, constitute in the intermediate circuit sheet layer 1 intermediate closed loop metal shielding layer 7 with side closed loop shielding enclosure between lower floor's metal shielding layer 3.

Example 32:

on the basis of the embodiment 3, as shown in fig. 6, the side closed-loop shielding enclosure is of an integral structure; be equipped with the blind groove 6 of closed loop of end to end on upper strata metal shielding layer 2, just the blind groove 6 of closed loop runs through in proper order upper strata metal shielding layer 2 with interlaminar electrical insulation layer 4 between intermediate line sheet layer 1 intermediate closed loop metal shielding layer 7 and intermediate line sheet layer 1 with interlaminar electrical insulation layer 4 between the metal shielding layer 3 of lower floor, and end in lower floor metal shielding layer 3, the tank bottom of blind groove 6 of closed loop does lower floor metal shielding layer 3, electroplate or fill in the blind groove 6 of closed loop has conducting material, constitutes a body structure the closed loop shielding enclosure of side.

Example 33:

on the basis of the embodiment 3, as shown in fig. 7, the side closed-loop shielding enclosure is of an integral structure; be equipped with the blind groove 6 of closed loop of end to end on lower floor's metallic shield layer 3, just the blind groove 6 of closed loop runs through in proper order lower floor's metallic shield layer 3 with interlaminar electrical insulation layer 4 between the intermediate line sheet layer 1 intermediate closed loop metallic shield layer 7 and intermediate line sheet layer 1 with interlaminar electrical insulation layer 4 between the upper metal shielding layer 2, and end in upper metal shielding layer 2, the tank bottom of the blind groove 6 of closed loop does upper metal shielding layer 2, electroplate or fill in the blind groove 6 of closed loop has conducting material, constitutes a body structure the side shielding enclosure.

Example 4:

as shown in fig. 8, 9, 10 and 12: a circuit board with an electromagnetic shielding structure comprises a middle circuit board layer 1, and an upper metal shielding layer 2 and a lower metal shielding layer 3 which are correspondingly covered on the upper surface and the lower surface of the middle circuit board layer 1, wherein interlayer electric insulating layers 4 are respectively arranged between the middle circuit board layer 1 and the upper metal shielding layer 2 and between the middle circuit board layer 1 and the lower metal shielding layer 3, and a conducting circuit 5 is arranged in the middle circuit board layer 1; the upper metal shielding layer 2 and the lower metal shielding layer 3 are electrically communicated through a side closed-loop shielding enclosure wall embedded between the upper metal shielding layer 2 and the lower metal shielding layer 3, and the conducting circuit 5 in the middle circuit board layer 1 is enclosed in the side closed-loop shielding enclosure wall; the side closed-loop shielding wall is formed by electroplating or filling conductive materials in closed-loop blind grooves 6 which are connected end to end.

Preferably, a plurality of laminated intermediate circuit board layers 1 are arranged between the upper metal shielding layer 2 and the lower metal shielding layer 3, the interlayer electrical insulation layer 4 is arranged between the upper metal shielding layer 2 and the intermediate circuit board layer 1 adjacent to the upper metal shielding layer (which means the upper metal shielding layer 2), the interlayer electrical insulation layer 4 is arranged between the lower metal shielding layer 3 and the intermediate circuit board layer 1 adjacent to the lower metal shielding layer (which means the lower metal shielding layer 3), and the interlayer electrical insulation layer 4 is arranged between every two adjacent intermediate circuit board layers 1; the conducting circuit 5 is arranged on each layer of the middle circuit board layer 1, and the middle closed-loop metal shielding layer 7 with a preset width is embedded in each layer of the middle circuit board layer 1 and around the conducting circuit 5; the upper metal shielding layer 2, the lower metal shielding layer 3 and the middle closed-loop metal shielding layer 7 in the multiple middle circuit board layers 1 are electrically communicated through a side closed-loop shielding enclosure wall embedded between the upper metal shielding layer 2 and the lower metal shielding layer 3; the conducting wires 5 in all the middle circuit board layers 1 are enclosed in the side closed-loop shielding enclosing wall; the upper metal shielding layer 2, the side closed-loop shielding enclosure, all the middle closed-loop metal shielding layers 7 and the lower metal shielding layers 3 jointly form an electromagnetic shielding structure of all the conducting circuits 5 in the middle circuit board layer 1.

Example 41:

on the basis of embodiment 4, as shown in fig. 8, the side closed-loop shielding enclosure wall is a multi-layered split structure and is electrically connected through the corresponding intermediate closed-loop metal shielding layer 7; the upper metal shielding layer 2 is provided with closed-loop blind grooves 6 which are connected end to end, the closed-loop blind grooves 6 on the upper metal shielding layer 2 penetrate through the corresponding interlayer electric insulating layer 4, or penetrate through the corresponding interlayer electric insulating layer 4 and the corresponding intermediate closed-loop metal shielding layer 7, and are correspondingly stopped at the intermediate closed-loop metal shielding layer 7 adjacent to or alternated with the upper metal shielding layer 2, and the bottom of the closed-loop blind grooves 6 on the upper metal shielding layer 2 is the intermediate closed-loop metal shielding layer 7 adjacent to or alternated with the upper metal shielding layer 2; the closed-loop blind groove 6 on the upper metal shielding layer 2 is plated or filled with a conductive material to form a side closed-loop shielding enclosure wall between the upper metal shielding layer 2 and the middle closed-loop metal shielding layer 7 in the middle circuit board layer 1 adjacent to or spaced with (the upper metal shielding layer 2); or/and closed-loop blind grooves 6 which are connected end to end are arranged on the lower metal shielding layer 3, the closed-loop blind grooves 6 which are positioned on the lower metal shielding layer 3 penetrate through the corresponding interlayer electric insulating layer 4, or penetrate through the corresponding interlayer electric insulating layer 4 and the corresponding intermediate closed-loop metal shielding layer 7 and are correspondingly stopped at the intermediate closed-loop metal shielding layer 7 which is adjacent to or alternated with the lower metal shielding layer 3, and the groove bottoms of the closed-loop blind grooves 6 which are positioned on the lower metal shielding layer 3 are the intermediate closed-loop metal shielding layers 7 which are adjacent to or alternated with the lower metal shielding layer 3; the closed-loop blind groove 6 on the lower metal shielding layer 3 is plated or filled with a conductive material to form a side closed-loop shielding fence between the lower metal shielding layer 3 and the intermediate closed-loop metal shielding layer 7 in the intermediate circuit board layer 1 adjacent to or spaced from the lower metal shielding layer 3; or/and in the continuous multilayer intermediate circuit board layer 1, the intermediate circuit board layer 1 positioned at one end is a first intermediate circuit board layer 11, and the intermediate circuit board layer 1 positioned at the other end is a second intermediate circuit board layer 12; a closed-loop blind slot 6 is formed in the middle metal shielding layer 7 of the first middle circuit board layer 11, and the closed-loop blind slot 6 located in the middle metal shielding layer 7 penetrates through the corresponding interlayer electrical insulating layer 4, or penetrates through the corresponding interlayer electrical insulating layer 4 and the corresponding middle closed-loop metal shielding layer 7, and ends at the middle metal shielding layer 7 of the second middle circuit board layer 12; and the closed-loop blind grooves 6 on the intermediate metal shielding layers 7 are plated or filled with conductive materials to form a side closed-loop shielding enclosure wall between the intermediate closed-loop metal shielding layers 7 in the continuous multilayer intermediate circuit board layers 1.

Example 42:

on the basis of the embodiment 4, as shown in fig. 9, the side closed-loop shielding enclosure wall is of an integral structure; be equipped with the blind groove 6 of closed loop of end to end on the upper metal shielding layer 2, just the blind groove 6 of closed loop runs through all interlayer electrical insulation layer 4 and all middle closed loop metal shielding layer 7 ends in lower floor's metal shielding layer 3, the tank bottom of the blind groove 6 of closed loop does lower floor's

metal shielding layer

3, 6 interior platings of the blind groove of closed loop or packing have conducting material, constitute an organic whole structure the closed loop shielding enclosure of side.

Example 43:

on the basis of embodiment 4, as shown in fig. 10, the closed-loop blind grooves 6 connected end to end are formed in the lower metal shielding layer 3, the closed-loop blind grooves 6 penetrate through all the interlayer electrical insulation layers 4 and all the intermediate closed-loop metal shielding layers 7 and end at the upper metal shielding layer 2, the groove bottom of the closed-loop blind grooves 6 is the upper metal shielding layer 2, and conductive materials are electroplated or filled in the closed-loop blind grooves 6 to form the side shielding enclosure wall of an integrated structure.

In any one or more of the above embodiments: the conductive circuit 5 in the intermediate circuit board layer 1 is provided with a signal circuit, and the signal circuit comprises a signal input circuit or/and a signal output circuit;

the side shielding enclosure wall is provided with a gap, or/and a blind hole is arranged in an isolation area which is divided in advance by the upper metal shielding layer or the lower metal shielding layer;

the signal line sets up outer warp of side closed loop shielding enclosure in middle circuit board layer 1 the breach with the electrically conductive line 5 electricity intercommunication of middle circuit board layer 1, or/and, the signal line sets up upper metal shielding layer 2 or the isolation region that lower floor's metal shielding layer 3 demarcated in advance is in, and the warp the blind hole with electrically conductive line 5 electricity intercommunication in the middle circuit board layer 1.

In embodiment 3 or/and embodiment 4, as shown in fig. 11, the intermediate closed-loop metal shielding layer 7 is more a copper foil line with a certain width, and is designed in the intermediate circuit board layer 1 to surround the conductive circuit 5; the intermediate closed-loop metal shielding layer 7 has the main idea that the intermediate closed-loop metal shielding layer plays a role of an intermediate pile foundation, reduces the depth of the closed-loop blind groove 6, improves the stability of the closed-loop blind groove 6 after electroplating or filling, and reduces the processing difficulty of the closed-loop blind groove 6 due to the reduction of the depth of the closed-loop blind groove 6; otherwise, the closed-loop blind groove 6 is directly laser-milled from the upper metal shielding layer 2 to the lower metal shielding layer 3, on one hand, the depth is difficult to process, and on the other hand, the depth of the closed-loop blind groove 6 is too deep, so that the electroplating or filling reliability and the mechanical connection reliability are poor. In a word, the intermediate closed-loop metal shielding layer 7 is designed on the intermediate circuit board layer 1, and due to the reduction of the depth of the closed-loop blind groove 6, the laser processing difficulty of the closed-loop blind groove 6 is reduced, the difficulty of electroplating or filling the closed-loop blind groove is reduced, the mechanical connection reliability of the closed-loop blind groove 6 is improved, and the electromagnetic shielding reliability of the circuit board is improved.

Because the circuit board of high-frequency signals needs to adopt materials with small signal transmission loss, especially the current popular 5G materials, such as modified polyimide MPI material or liquid crystal high polymer L CP material or Teflon PTFE material, which are not temperature-resistant or can be very easily layered with the laminated metal or the laminated glue layer when heated, therefore, the closed-loop blind slot mode is adopted to electrically connect the upper and lower metal shielding layers, thereby avoiding the shrinkage or cracking of the hole wall material of the through hole caused by the direct laser drilling through hole mode between the upper and lower metal shielding layers, the quality defect that the electroplating or filling quality is not too high and the glue shrinkage is too large (electroplating or plated through hole slice metal burr).

In any one or more of the above embodiments, the interlayer electrical insulating layer 4 is a modified polyimide MPI material or a liquid crystal high molecular polymer L CP material or a teflon PTFE material.

With the rise of the domestic 5G market, PTFE consumption is greatly increased in the field of high-frequency copper-clad plates, a high-frequency transmission technology is one of the key technologies of 5G wireless communication, materials with low dielectric constant and low dielectric loss are required to be used for realizing high-frequency transmission, the low-dielectric constant materials are mainly used for antenna materials, circuit board materials, cover plate materials and shell materials of 5G mobile phones, and the low-dielectric constant materials are PTFE, L CP and MPI at present.

Wherein PTFE is a polymer material with the lowest dielectric constant in the current organic materials! The Df value is less than 0.002, namely the insulation performance is best, and the dielectric performance requirement of the copper-clad plate in 5G equipment can be best met.

L CP (liquid crystal polymer material), as a new material, is very suitable for microwave and millimeter wave devices, and has a good application prospect in the 5G era in the future, the multi-layer L CP antenna is very suitable for high frequency band, and is expected to become a preferred material for a mobile phone antenna from the viewpoint of cost performance, in a strict sense, the L CP antenna is called as an FPC soft board using L CP as a base material, and bears partial antenna functions.

Please note that, the main low dielectric constant materials are PTFE, L CP and MPI, and the circuit board constructed by these materials becomes extremely difficult and inefficient due to the copper contained in the middle, because these materials are easily delaminated from the adhesive layer during the laser via drilling, and the product is scrapped, which is why the present invention considers that the blind slot is used to electrically connect the upper metal shielding layer and the lower metal shielding layer, and avoid the conventional laser via drilling (involving drilling several metal layers, such as three copper layers), and the first-order blind slot is used, only the upper metal shielding layer or the lower metal shielding layer needs to be drilled at this time, and then only the interlayer electrical insulating layer needs to be processed to form the first-order blind slot, so as to better protect the low dielectric constant insulating material from delamination from the adhesive, thereby improving the processing efficiency of the product, improving the quality of the product, and further reducing the cost.

In any one or more of the above embodiments: and the surface of the upper metal shielding layer 2 or/and the lower metal shielding layer 3 is covered with an electromagnetic shielding film or an insulating film.

In any one or more of the above embodiments: when the closed-loop blind groove 6 is subjected to electroplating treatment, a layer of conductive material can be electroplated along the groove wall and bottom of the closed-loop blind groove 6, or the closed-loop blind groove 6 can be completely electroplated, so that the conductive material fills the closed-loop blind groove 6.

The circuit board structure is very suitable for the structural design of a 5G antenna board, and is a most suitable structure no matter a receiving antenna or a transmitting antenna of a 5G mobile phone. An antenna (antenna) is a transducer between a radio wave propagating in space and a current moving in a metallic conductor. In transmission, a radio transmitter supplies a current to a terminal of an antenna, which generates an electromagnetic wave from current radiation energy; on reception, the antenna intercepts some of the radio waves' ability, generates a current at its terminal, and applies the current to the receiver for amplification. Antennas are an important component of all radio devices, and all devices that use electromagnetic waves to transmit information, such as radio, television, cell phones, and internet of things and automotive communications, require the presence of antennas. Since the electromagnetic wave generates loss in the process of space transmission, the gain of the antenna, the loss of the antenna and the transmission line for transmitting the radio frequency energy by the transceiver, the transmitting power of the transmitter and the sensitivity of the receiver are all important factors influencing the transmission performance of the antenna. Furthermore, electromagnetic waves are reflected, absorbed and eliminated by metal, thereby causing signal shielding, and electronic components easily interfere with the electromagnetic waves, so that the antenna needs to be placed far away from metal parts and interfering components in design.

The problems can be solved easily if the antenna is subjected to electromagnetic shielding, and therefore, the invention is applied to a 5G antenna board and has great economic value.

In any one or more of the above embodiments, the electromagnetic shielding structure is provided with a ground terminal.

The invention also provides a manufacturing method of the circuit board with the electromagnetic shielding structure, which is used for manufacturing the circuit board with the electromagnetic shielding structure.

A method for manufacturing a circuit board with an electromagnetic shielding structure comprises the steps that the circuit board manufactured by the method comprises a middle circuit board layer, an upper metal shielding layer and a lower metal shielding layer, wherein the upper metal shielding layer and the lower metal shielding layer correspondingly cover the upper surface and the lower surface of the middle circuit board layer; the middle circuit board layer is internally provided with a conductive circuit;

the manufacturing method comprises the following steps of,

Preferably, the upper metal shielding layer and/or the lower metal shielding layer are/is pre-arranged on the surface of the interlayer electrical insulation layer, and the closed-loop blind slot is processed on the surface of the upper metal shielding layer and/or the lower metal shielding layer by laser; or the upper metal shielding layer and/or the lower metal shielding layer are/is synchronously formed on the surface of the interlayer electric insulating layer when the closed-loop blind slot is electroplated or filled, and then the closed-loop blind slot is processed on the surface of the interlayer electric insulating layer by adopting laser.

The manufacturing method of the invention adopts laser to process the closed-loop blind slot on the precast slab, and then electroplates or fills the conductive material; the prefabricated plate is manufactured by a circuit board processing flow.

Example 1: as shown in fig. 13 and 15, the prefabricated slab includes a middle circuit board layer 1, and an upper metal shielding layer 2 and a lower metal shielding layer 3 correspondingly covering the upper and lower surfaces of the middle circuit board layer 1, wherein an interlayer electrical insulation layer 4 is respectively disposed between the middle circuit board layer 1 and the upper metal shielding layer 2 and between the middle circuit board layer 1 and the lower metal shielding layer 3, and a conductive circuit 5 is disposed in the middle circuit board layer. In fig. 13, the closed-loop blind groove 6 is processed on the surface of the upper metal shielding layer 2 by using laser, the bottom of the closed-loop blind groove 6 is the lower metal shielding layer 3, and finally, a conductive material is electroplated or filled in the closed-loop blind groove 6 to form a side closed-loop shielding enclosure wall.

Example 2: as shown in fig. 14 and 16, the prefabricated slab includes an intermediate circuit slab layer 1 and a lower metal shielding layer 3 correspondingly covering the lower surface of the intermediate circuit slab layer 1, an interlayer electrical insulation layer 4 is disposed between the intermediate circuit slab layer 1 and the lower metal shielding layer 3, a conductive circuit 5 is disposed in the intermediate circuit slab layer, and the interlayer electrical insulation layer 4 is also disposed on the upper surface of the intermediate circuit slab layer 1. In fig. 14, firstly, a closed-loop blind groove 6 is processed by laser on the interlayer electrical insulation layer 4 on the upper surface of the intermediate circuit board layer 1, the bottom of the closed-loop blind groove 6 is the lower metal shielding layer 3, then the closed-loop blind groove 6 is electroplated or filled, and the upper metal shielding layer 2 is formed on the surface of the interlayer electrical insulation layer 4 on the upper surface of the intermediate circuit board layer 1 synchronously when the closed-loop blind groove 6 is electroplated or filled, and simultaneously a side closed-loop shielding enclosure wall is formed.

Further, the specific steps of processing the closed-loop blind slot are,

firstly, chemically windowing the surface layer of a prefabricated slab by adopting chemical etching to form a closed-loop chemically windowed area, and then carrying out laser processing on the chemically windowed area by adopting low-peak laser to form a closed-loop blind groove until the bottom of the closed-loop blind groove is a target layer;

or firstly, carrying out laser windowing on the surface layer of the prefabricated slab by adopting a high-peak laser beam to form a closed-loop laser windowing region, and then, processing the closed-loop blind groove in the laser windowing region by adopting a low-peak laser until the bottom of the closed-loop blind groove is a target layer;

or, firstly, thinning and browning the surface layer of the precast slab (without browning, high reflectivity to carbon dioxide laser and no absorption), and then punching or cutting and closing by using the carbon dioxide laser to form the closed-loop blind groove until the bottom of the closed-loop blind groove is a target layer;

the precast slab surface layer is the upper metal shielding layer or the lower metal shielding layer or the interlayer electrical insulation layer surface, and the target layer is the lower metal shielding layer or the upper metal shielding layer.

The high-peak laser beam means that the laser peak power density of a laser processing focus exceeds the damage threshold of the upper metal shielding layer or/and the lower metal shielding layer or/and the middle closed-loop metal shielding layer; the low-peak laser beam means that the laser peak power density of a laser processing focus is lower than the damage threshold of a closed-loop blind groove bottom material, and the closed-loop blind groove bottom material can be an upper-layer metal shielding layer or/and a lower-layer metal shielding layer or/and an intermediate closed-loop metal shielding layer. In addition, the window is opened on the surface layer of the precast slab by chemical etching, and the window opening is generally completed by photoetching, developing and wet etching; when the middle closed-loop metal shielding layer 7 does not need to be etched, the interlayer electric insulating layer 4 is removed by adopting low-peak laser, and the middle closed-loop metal shielding layer 7 is not damaged or is slightly damaged.

Furthermore, a middle closed-loop metal shielding layer with a preset width is embedded in the middle circuit board layer and positioned around the conducting circuit; the prefabricated plate surface layer is the upper metal shielding layer or the lower metal shielding layer or the interlayer electric insulation layer surface, and the target layer is the lower metal shielding layer or the upper metal shielding layer or the middle closed-loop metal shielding layer.

Example 3: as shown in fig. 17, the prefabricated slab includes middle circuit board layer 1 and corresponds the cover upper metal shielding layer 2 on the middle circuit board layer 1, the middle circuit board layer with be equipped with interlaminar electrical insulation layer 4 between the upper metal shielding layer 2, be equipped with conducting wire 5 in the middle circuit board layer 1 and be located in the middle circuit board layer 1 and inlay the middle closed loop metal shielding layer 7 that has preset width around conducting wire 5. In fig. 17, the surface of the upper metal shielding layer 2 is processed with the closed-loop blind groove 6 by using laser, the bottom of the closed-loop blind groove 6 is the intermediate closed-loop metal shielding layer 7 in the intermediate circuit board layer 1, and finally, the closed-loop blind groove 6 is plated or filled with a conductive material to form a side closed-loop shielding enclosure.

In fig. 15, 16 and 17, the conductive traces 5 of the intermediate circuit board layer 1 and the intermediate closed-loop metal shielding layer 7 arranged around the conductive traces are manufactured by a circuit board processing flow. Specifically, while the conductive circuit 5 of the intermediate circuit board layer 1 is manufactured by the processes of photolithography, development, etching and the like, the intermediate closed-loop metal shielding layer 7 on the outer side of the conductive circuit is synchronously processed on the same metal layer, generally a copper layer.

Preferably, the manufacturing method of the present invention further includes a step of manufacturing a signal line for the conductive line, where the signal line includes a signal input line or/and a signal output line;

the specific steps for fabricating the signal lines are,

the outer preparation of side closed loop shielding enclosure in the intermediate line sheet layer signal line, and the warp the breach with the conducting wire electricity intercommunication of intermediate line sheet layer, or/and upper metal shielding layer or the preparation in the isolation region that lower floor's metal shielding layer demarcated in advance signal line, and the warp the blind hole with conducting wire electricity intercommunication in the intermediate line sheet layer.

The following is a more specific example.

Example one: manufacture of single-layer circuit board

Referring to fig. 5, firstly, the middle circuit board layer 1 and the lower metal shielding layer 3 are laminated together through the interlayer electrical insulating layer 4, the interlayer electrical insulating layer 4 can be selected to be a flexible copper clad laminate FCC L of liquid crystal high molecular polymer L CP, the middle circuit board layer 1 and the lower metal shielding layer 3 are both 12 micron electrolytic copper foils, at this time, according to the design, according to the circuit board manufacturing process, glue is coated on the surface of the middle circuit board layer 1, photoetching and developing are performed, the required conductive circuits 5 are etched, the conductive circuits 5 are distributed in the middle area of the middle circuit board layer 1, meanwhile, the middle closed-loop metal shielding layer 7 of the middle circuit board layer 1 is manufactured, the closed-loop metal shielding layer 7 surrounds the conductive circuits 5, at this time, the upper metal shielding layer 2 is laminated on the surface of the middle circuit board layer 1 through the interlayer insulating layer 4, please note that the interlayer insulating layer 4 between the upper metal shielding layer 2 and the middle circuit board layer 1 can be a lamination of L CP and a glue, the glue is also a glue with low signal loss, therefore, the adhesion property is not good, the heat can be laminated with L CP, the upper metal shielding layer 2 and the middle circuit shielding layer 2 and the intermediate metal shielding layer 1 can be laminated through the interlayer insulating layer 4, the interlayer insulating layer, the intermediate metal shielding layer 4, the intermediate metal shielding layer can be laminated, the intermediate shielding layer laminated.

Further, a laser blind hole machine is adopted to drill a closed-loop blind groove at a designed place of the prefabricated slab, ultraviolet laser is adopted to drill the closed-loop blind groove, the closed-loop blind groove drilling is respectively carried out from the surface of the upper metal shielding layer 2 and the surface of the lower metal shielding layer 3 to the interior of the prefabricated slab, the closed-loop blind groove on the surface of the upper metal shielding layer 2 and the closed-loop blind groove on the surface of the lower metal shielding layer 3 are respectively formed, the electroplating of the closed-loop blind grooves 6 on the front side and the back side of the prefabricated slab is finished through the processes of plasma cleaning, micro etching, black hole, electroplating and the like, and the manufacturing of the electromagnetic shielding structure of the prefabricated slab is finished, so that the circuit board with the electromagnetic shielding.

The section of the middle closed-loop metal shielding layer 7 of the middle circuit board layer 1 is from left to right and penetrates through the whole circuit board, and the closed-loop blind groove 6 on the surface of the upper-layer metal shielding layer 2 is electrically communicated with the middle closed-loop metal shielding layer 7 through electroplating or filling a conductive material; similarly, the closed-loop blind groove 6 on the surface of the lower metal shielding layer 3 is electrically communicated with the intermediate closed-loop metal shielding layer 7 through electroplating or filling a conductive material; the upper metal shield layer 2, the intermediate closed-loop metal shield layer 7 and the lower metal shield layer 3 are thus in electrical communication through a closed-loop blind slot plated or filled with a conductive material, which together constitute a spatial electromagnetic shielding protection of the conductive line 5 of the intermediate circuit board layer 1.

The electromagnetic shielding structure of the circuit board is simple, convenient to produce and capable of skillfully avoiding thermal delamination between insulating materials (L CP and viscose) with low dielectric constants, so that the circuit board can be produced stably and smoothly in batches.

Example two: fabrication of multilayer Wiring Board (two layer Wiring Board in this example)

Referring to fig. 8, this is a multi-layer 5G antenna board with electromagnetic shielding function, and its production process may be as follows:

the method comprises the following steps that firstly, a middle circuit board layer 1 of a first layer and a lower metal shielding layer 3 of the first layer are overlapped through an interlayer electric insulating layer 4, the interlayer electric insulating layer 4 can be selected to be a flexible copper clad laminate FCC L of liquid crystal high polymer L CP, the middle circuit board layer 1 of the first layer and the lower metal shielding layer 3 of the first layer are both 12-micron electrolytic copper foils, at the moment, according to design and circuit board manufacturing procedures, glue is coated on the surface of the middle circuit board layer 1 of the first layer, photoetching and developing are carried out, needed conducting circuits 5 are etched, the conducting circuits 5 are distributed in the middle area of the middle circuit board layer 1, meanwhile, a middle closed-loop metal shielding layer 7 of the middle circuit board layer 1 of the first layer is manufactured, and.

And secondly, laminating the middle circuit board layer 1 of the second layer on the surface of the middle circuit board layer 1 of the first layer through the interlayer insulating layer 4, wherein please note that the interlayer insulating layer 4 can be a laminated structure of glue + L CP, the glue is glue with low signal loss, so that the adhesiveness is poor, and the glue can be layered with L CP when heated, in the laminating and bonding process of the middle circuit board layer 1 of the second layer and the middle circuit board layer 1 of the first layer through the interlayer insulating layer 4, part of the glue can permeate into the middle circuit board layer 1 of the first layer, and an insulating layer between the middle closed-loop metal shielding layer 7 and the conducting circuit 5 is formed in the middle circuit board layer 1 of the first layer.

And thirdly, according to design, according to a circuit board manufacturing process, coating glue on the surface of the middle circuit board layer 1 on the second layer, photoetching and developing, etching a required conductive circuit 5 in the middle circuit board layer 1 on the second layer, wherein the conductive circuit 5 is distributed in the middle area of the middle circuit board layer 1, meanwhile, a middle closed-loop metal shielding layer 7 of the middle circuit board layer 1 on the first layer is manufactured, and the closed-loop metal shielding layer 7 surrounds the conductive circuit 5.

And fourthly, drilling a closed-loop blind groove in the designed place of the circuit board by using a laser blind hole machine, wherein drilling a closed-loop blind groove by using ultraviolet laser blind holes is carried out, drilling a closed-loop blind groove from the surface of the middle closed-loop metal shielding layer 7 of the middle circuit board layer 1 of the second layer to the inside of the circuit board to form a notch on the surface of the middle closed-loop metal shielding layer 7 of the middle circuit board layer 1 of the second layer, and completing the electric connection of the closed-loop blind groove hole 6 between the middle closed-loop metal shielding layer 7 of the middle circuit board layer 1 of the first layer and the middle closed-loop metal shielding layer 7 of the middle circuit board layer 1 of the second layer through processes such as plasma cleaning, micro etching, black holes, electroplating and the like. Generally, the closed-loop blind slot is suggested to adopt a filling plating process, namely, an electroplating mode is adopted to fully electroplate the closed-loop blind slot 6 between the middle closed-loop metal shielding layer 7 of the middle circuit board layer 1 of the first layer and the middle closed-loop metal shielding layer 7 of the middle circuit board layer 1 of the second layer, so that the pressing and blind slot drilling of the subsequent working procedure are facilitated.

And fifthly, laminating the upper metal shielding layer 2 on the surface of the middle circuit board layer 1 of the second layer through the interlayer electric insulation layer 4, wherein please note that the interlayer electric insulation layer 4 can be a lamination of L CP and a layer of glue, which is a glue with low signal loss and therefore has poor adhesion and can be layered with L CP when heated, in the laminating and bonding process of the upper metal shielding layer 2 and the middle circuit board layer 1 of the second layer through the interlayer electric insulation layer 4, part of the glue can permeate into the middle circuit board layer 1 of the second layer, and an insulation layer between the middle closed-loop metal shielding layer 7 and the conductive circuit 5 is formed in the middle circuit board layer 1 of the second layer, so that the lamination and bonding of the lower metal shielding layer 3, the interlayer electric insulation layer 4, the middle circuit board layer 1 of the first layer, the interlayer electric insulation layer 4, the middle circuit board layer 1 of the second layer, the interlayer electric insulation layer 4 and the upper metal shielding layer 2 are completed, and the prefabricated board is formed.

And sixthly, drilling blind hole holes at the designed place of the circuit board by using a laser blind hole machine, wherein drilling blind closed-loop grooves in the circuit board is carried out from the surface of the upper metal shielding layer 2 and the surface of the lower metal shielding layer 3 by using ultraviolet laser blind holes, the blind closed-loop grooves in the surface of the upper metal shielding layer 2 and the blind closed-loop grooves in the surface of the lower metal shielding layer 3 are respectively formed, and electroplating or filling of the blind closed-loop grooves 6 on the front side and the back side of the circuit board is completed by processes such as plasma cleaning, micro-etching, black hole electroplating (or filling), and the like, so that the electromagnetic shielding structure of the circuit board is manufactured.

In the multilayer circuit board, because the middle circuit board layer has two or more than two layers, and the upper and lower metal shielding layers are added, the whole circuit board becomes thicker, and at the moment, if the conductive through holes are adopted to connect the upper and lower metal shielding layers (note that the high-frequency signal insulating material is not heat-resistant and can not be mechanically drilled), the laser through hole drilling is more difficult. The manufacturing method adopts a second-order blind slot processing mode, wherein the second-order blind slot processing mode is that the second-order blind slot passes through the middle metal shielding layer of one middle circuit layer and exposes the middle metal shielding layer of the next middle circuit layer.

The circuit board preparation all is that the lamination is laminated layer upon layer, when the number of piles is not so much yet, can make blind buried hole when the number of piles is not so much, still be one-order blind groove between last one deck intermediate line sheet layer and upper and lower metal shielding layer like this, the shielding layer of conducting wire side is broken up the whole into parts the preparation, has reduced the preparation degree of difficulty.

By adopting the method of embedding the blind slot, theoretically, the lead line with infinite layers and electromagnetic shielding capability can be manufactured.

In one or both of the examples one and two,

the method also comprises the step of manufacturing a signal line for the conductive circuit 5 of the intermediate circuit board layer 1, wherein the signal line comprises a signal input line or/and a signal output line and is used for exchanging signals with the outside.

The specific steps for manufacturing the signal line are as follows: the conducting circuit in the middle circuit board layer is provided with a signal circuit, and the signal circuit comprises a signal input circuit or/and a signal output circuit;

The circuit board with the electromagnetic shielding structure and the manufacturing method thereof provided by the invention have the following advantages:

1. the upper and lower metal shielding layers are electrically communicated through the closed-loop blind groove, a continuous and closed electromagnetic shielding environment (electromagnetic shielding structures are arranged on the upper and lower sides and on the periphery of the side face) is formed for the middle conductive circuit board, and the electromagnetic shielding effect is good.

2. The closed-loop blind slot is adopted to connect the upper metal shielding layer and the lower metal shielding layer, and the production efficiency is higher than that of the direct through hole connection of the upper metal shielding layer and the lower metal shielding layer, and the quality is more stable and reliable.

Because the circuit board of high frequency signal needs to adopt the material that signal transmission loss is little, especially current popular 5G material, for example modified polyimide MPI material or liquid crystal high polymer L CP material or be teflon PTFE material, these materials surface energy are than lower, it is very easy with the viscose layering to heat, consequently, adopt blind groove mode electricity to communicate upper and lower layer metal shielding layer, avoided the direct laser between upper and lower layer metal shielding layer and bore the hole wall material that the hole mode caused and contract in the hole, the electroplating quality is not too close, the quality defect of gluing shrink too greatly.

3. In the middle circuit board layer, a middle closed-loop metal shielding layer is designed, the laser processing difficulty of the blind groove is reduced, the electroplating difficulty of the blind groove is reduced, the mechanical connection reliability of the blind groove is improved, and the electromagnetic shielding reliability of the circuit board is improved.

4. The invention provides a smart circuit board shielding structure idea, and a simplified and optimized processing scheme aiming at forming the shielding structure by processing and drilling the high-frequency circuit board insulating material, and is very suitable for stable and low-cost production in batches.

The reader should understand that in the description of this specification, reference to the description of the terms "one embodiment," "some embodiments," "an example," "a specific example" or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims

1. A circuit board with an electromagnetic shielding structure is characterized in that: the shielding layer comprises a middle circuit board layer, an upper metal shielding layer and a lower metal shielding layer, wherein the upper metal shielding layer and the lower metal shielding layer are correspondingly covered on the upper surface and the lower surface of the middle circuit board layer;

2. The wiring board with electromagnetic shielding structure of claim 1, wherein: the upper metal shielding layer is provided with closed-loop blind grooves which are connected end to end, the closed-loop blind grooves sequentially penetrate through an interlayer electric insulation layer between the upper metal shielding layer and the middle circuit board layer, a non-conductive circuit area of the middle circuit board layer and an interlayer electric insulation layer between the middle circuit board layer and the lower metal shielding layer and are stopped at the lower metal shielding layer, the bottom of each closed-loop blind groove is the lower metal shielding layer, and conductive materials are electroplated or filled in the closed-loop blind grooves to form the side closed-loop shielding enclosure wall;

or the like, or, alternatively,

be equipped with the blind groove of closed loop of end to end on the lower floor's metal shielding layer, just the blind groove of closed loop runs through in proper order lower floor's metal shielding layer with electric insulation between the intermediate line sheet layer interlayer between the intermediate line sheet layer the non-conducting circuit region and the intermediate circuit board with electric insulation between the upper metal shielding layer interlayer, and end in upper metal shielding layer, the tank bottom of blind groove of closed loop does upper metal shielding layer, the blind inslot of closed loop is electroplated or is filled there is conducting material, constitutes the closed loop shielding enclosure of side.

3. The wiring board with an electromagnetic shielding structure according to claim 2, wherein: a plurality of layers of laminated intermediate circuit board layers are arranged between the upper metal shielding layer and the lower metal shielding layer, the interlayer electric insulation layer is arranged between the upper metal shielding layer and the adjacent intermediate circuit board layer, the interlayer electric insulation layer is arranged between the lower metal shielding layer and the adjacent intermediate circuit board layer, the interlayer electric insulation layer is arranged between every two adjacent intermediate circuit board layers, and the conducting circuit is arranged on each intermediate circuit board layer;

the upper metal shielding layer is provided with the closed-loop blind grooves which are connected end to end, the closed-loop blind grooves penetrate through all interlayer electric insulation layers and all non-conducting circuit areas of the middle circuit board layer and are stopped at the lower metal shielding layer, the bottom of each closed-loop blind groove is the lower metal shielding layer, and conductive materials are electroplated or filled in the closed-loop blind grooves to form the side closed-loop shielding enclosure wall;

or the like, or, alternatively,

the lower layer metal shielding layer is provided with closed-loop blind grooves which are connected end to end, the closed-loop blind grooves penetrate through all interlayer electric insulation layers and all non-conducting circuit areas of the middle circuit board layer and are stopped at the upper layer metal shielding layer, the bottom of each closed-loop blind groove is the upper layer metal shielding layer, and conductive materials are electroplated or filled in the closed-loop blind grooves to form the side closed-loop shielding enclosure wall;

the conducting wires in all the middle circuit board layers are enclosed in the side closed-loop shielding enclosing wall;

the upper metal shielding layer, the side closed-loop shielding enclosure wall and the lower metal shielding layer jointly form an electromagnetic shielding structure of all conducting circuits in the middle circuit board layer.

4. The wiring board with electromagnetic shielding structure of claim 1, wherein: a middle closed-loop metal shielding layer with a preset width is embedded in the middle circuit board layer and positioned around the conducting circuit;

the upper metal shielding layer, the lower metal shielding layer and the middle closed-loop metal shielding layer in the middle circuit board layer are electrically communicated through a side closed-loop shielding enclosure wall embedded between the upper metal shielding layer and the lower metal shielding layer;

the upper metal shielding layer, the side closed-loop shielding enclosure wall, the middle closed-loop metal shielding layer and the lower metal shielding layer jointly form an electromagnetic shielding structure of the conducting circuit in the middle circuit board layer.

5. The wiring board with electromagnetic shielding structure of claim 4, wherein: the side closed-loop shielding enclosure wall is of an upper and lower split structure and is electrically communicated through the middle closed-loop metal shielding layer;

closed-loop blind grooves which are connected end to end are arranged on the upper metal shielding layer, the closed-loop blind grooves on the upper metal shielding layer penetrate through an interlayer electric insulating layer between the upper metal shielding layer and the middle circuit board layer and are stopped at the middle closed-loop metal shielding layer, the bottom of the closed-loop blind grooves on the upper metal shielding layer is the middle closed-loop metal shielding layer, and conductive materials are electroplated or filled in the closed-loop blind grooves on the upper metal shielding layer to form a side closed-loop shielding enclosure wall between the middle closed-loop metal shielding layer and the upper metal shielding layer in the middle circuit board layer;

and/or the first and/or second light sources,

be equipped with end to end's closed loop blind groove on lower floor's metal shielding layer, and be located on the metal shielding layer of lower floor the closed loop blind groove runs through lower floor's metal shielding layer with electric insulation between the layer of intermediate line sheet, and end in intermediate loop metal shielding layer is located on the metal shielding layer of lower floor the tank bottom of closed loop blind groove does intermediate loop metal shielding layer is located on the metal shielding layer of lower floor the blind inslot of closed loop is electroplated or is filled with conducting material, constitutes in the intermediate line sheet intermediate loop metal shielding layer with side closed loop shielding enclosure between the metal shielding layer of lower floor.

6. The wiring board with electromagnetic shielding structure of claim 4, wherein: the side closed-loop shielding enclosure wall is of an integral structure;

the upper metal shielding layer is provided with closed-loop blind grooves which are connected end to end, the closed-loop blind grooves sequentially penetrate through an interlayer electric insulation layer between the upper metal shielding layer and the middle circuit board layer, the middle closed-loop metal shielding layer and an interlayer electric insulation layer between the middle circuit board layer and the lower metal shielding layer and are stopped at the lower metal shielding layer, the bottom of each closed-loop blind groove is the lower metal shielding layer, and a conductive material is electroplated or filled in each closed-loop blind groove to form the side closed-loop shielding enclosure wall with an integral structure;

or the like, or, alternatively,

be equipped with the blind groove of end to end's closed loop on the metallic shield layer of lower floor, just the blind groove of closed loop runs through in proper order lower floor's metallic shield layer with electric insulation layer between the intermediate line sheet layer intermediate closed loop metallic shield layer and intermediate line sheet layer with electric insulation layer between the upper strata metallic shield layer, and end in upper strata metallic shield layer, the tank bottom in the blind groove of closed loop does upper strata metallic shield layer, the blind inslot of closed loop is electroplated or is filled there is conducting material, constitutes a body structure the side shielding enclosure.

7. The wiring board with electromagnetic shielding structure of claim 4, wherein: a plurality of laminated intermediate circuit board layers are arranged between the upper metal shielding layer and the lower metal shielding layer, the interlayer electric insulation layer is arranged between the upper metal shielding layer and the adjacent intermediate circuit board layer, the interlayer electric insulation layer is arranged between the lower metal shielding layer and the adjacent intermediate circuit board layer, and the interlayer electric insulation layer is arranged between every two adjacent intermediate circuit board layers;

the conducting circuit is arranged on each layer of the middle circuit board layer, and the middle closed-loop metal shielding layer with a preset width is embedded in each layer of the middle circuit board layer and positioned around the conducting circuit;

the upper metal shielding layer, the lower metal shielding layer and the middle closed-loop metal shielding layer in the multiple middle circuit board layers are electrically communicated through a side closed-loop shielding enclosure wall embedded between the upper metal shielding layer and the lower metal shielding layer;

the upper metal shielding layer, the side closed-loop shielding enclosure wall, all the middle closed-loop metal shielding layer and the lower metal shielding layer jointly form an electromagnetic shielding structure of all the conducting circuits in the middle circuit board layer.

8. The wiring board with an electromagnetic shielding structure according to claim 7, wherein: the side closed-loop shielding enclosure wall is of a multi-layer layered split structure and is electrically communicated through the corresponding middle closed-loop metal shielding layer;

the upper metal shielding layer is provided with closed-loop blind grooves which are connected end to end, the closed-loop blind grooves on the upper metal shielding layer penetrate through the corresponding interlayer electric insulating layer, or penetrate through the corresponding interlayer electric insulating layer and the corresponding intermediate closed-loop metal shielding layer and correspondingly stop at the intermediate closed-loop metal shielding layer which is adjacent to or alternated with the upper metal shielding layer, and the bottom of the closed-loop blind grooves on the upper metal shielding layer is the intermediate closed-loop metal shielding layer which is adjacent to or alternated with the upper metal shielding layer; the closed-loop blind groove on the upper metal shielding layer is plated or filled with a conductive material to form a side closed-loop shielding enclosure wall between the upper metal shielding layer and the middle closed-loop metal shielding layer in the middle circuit board layer adjacent to or spaced from the upper metal shielding layer;

and/or the first and/or second light sources,

the lower metal shielding layer is provided with closed-loop blind grooves which are connected end to end, the closed-loop blind grooves on the lower metal shielding layer penetrate through the corresponding interlayer electric insulating layer, or penetrate through the corresponding interlayer electric insulating layer and the corresponding intermediate closed-loop metal shielding layer and correspondingly stop at the intermediate closed-loop metal shielding layer which is adjacent to or alternate with the lower metal shielding layer, and the bottom of the closed-loop blind grooves on the lower metal shielding layer is the intermediate closed-loop metal shielding layer which is adjacent to or alternate with the lower metal shielding layer; the closed-loop blind grooves on the lower metal shielding layer are plated or filled with conductive materials to form a side closed-loop shielding enclosure wall between the lower metal shielding layer and the middle closed-loop metal shielding layers in the middle circuit board layer adjacent to or spaced with the lower metal shielding layer;

and/or the first and/or second light sources,

in the continuous multilayer intermediate circuit board layers, the intermediate circuit board layer positioned at one end is made to be a first intermediate circuit board layer, and the intermediate circuit board layer positioned at the other end is made to be a second intermediate circuit board layer;

the middle metal shielding layer of the first middle circuit board layer is provided with a closed-loop blind slot, and the closed-loop blind slot penetrates through the corresponding interlayer electric insulating layer, or penetrates through the corresponding interlayer electric insulating layer and the corresponding middle closed-loop metal shielding layer and ends at the middle metal shielding layer of the second middle circuit board layer; and electroplating or filling a conductive material in the closed-loop blind groove to form a side closed-loop shielding enclosure wall between the intermediate closed-loop metal shielding layers in the continuous multilayer intermediate circuit board layers.

9. The wiring board with an electromagnetic shielding structure according to claim 7, wherein: the side closed-loop shielding enclosure wall is of an integral structure;

the upper metal shielding layer is provided with closed-loop blind grooves which are connected end to end, the closed-loop blind grooves penetrate through all the interlayer electric insulating layers and all the middle closed-loop metal shielding layers and are stopped at the lower metal shielding layer, the bottom of each closed-loop blind groove is the lower metal shielding layer, and conductive materials are electroplated or filled in the closed-loop blind grooves to form the side closed-loop shielding enclosure wall with an integrated structure;

or the like, or, alternatively,

be equipped with end to end's closed loop blind groove on the metal shielding layer of lower floor, just closed loop blind groove runs through all interlayer electrical insulation layer and all middle closed loop metal shielding layer ends in upper metal shielding layer, the tank bottom of closed loop blind groove does upper metal shielding layer, electroplate or fill in the closed loop blind groove has conducting material, constitutes integrative structure the side shielding enclosure.

10. A wiring board with an electromagnetic shielding structure according to any one of claims 1 to 9, wherein: the conducting circuit in the middle circuit board layer is provided with a signal circuit, and the signal circuit comprises a signal input circuit or/and a signal output circuit;

the signal line sets up the outer warp of side closed loop shielding enclosure in the intermediate line sheet layer the breach with the conducting wire electricity intercommunication of intermediate line sheet layer, or/and, the signal line sets up upper metal shielding layer or the isolation region that lower floor's metal shielding layer demarcated in advance is in, and the warp the blind hole with conducting wire electricity intercommunication in the intermediate line sheet layer.

11. The wiring board with an electromagnetic shielding structure according to any one of claims 1 to 9, wherein the interlayer electrical insulating layer is a Modified Polyimide (MPI) material or a liquid crystal polymer L CP material or a Teflon (PTFE) material.

12. A wiring board with an electromagnetic shielding structure according to any one of claims 1 to 9, wherein: and an electromagnetic shielding film or an insulating film is covered on the surface of the upper metal shielding layer or/and the lower metal shielding layer.

13. A wiring board with an electromagnetic shielding structure according to any one of claims 1 to 9, wherein: the electromagnetic shielding structure is provided with a grounding terminal.

14. A manufacturing method of a circuit board with an electromagnetic shielding structure is characterized in that: the circuit board manufactured by the manufacturing method comprises a middle circuit board layer, an upper metal shielding layer and a lower metal shielding layer, wherein the upper metal shielding layer and the lower metal shielding layer are correspondingly covered on the upper surface and the lower surface of the middle circuit board layer; the middle circuit board layer is internally provided with a conductive circuit;

the manufacturing method comprises the following steps of,

15. A method for manufacturing a circuit board having an electromagnetic shielding structure according to claim 14, wherein: the upper metal shielding layer and/or the lower metal shielding layer are/is arranged on the surface of the interlayer electrical insulation layer in advance, and the closed-loop blind slot is processed on the surface of the upper metal shielding layer and/or the lower metal shielding layer by adopting laser;

or the upper metal shielding layer and/or the lower metal shielding layer are/is synchronously formed on the surface of the interlayer electric insulating layer when the closed-loop blind slot is electroplated or filled, and then the closed-loop blind slot is processed on the surface of the interlayer electric insulating layer by adopting laser.

16. A method for manufacturing a circuit board having an electromagnetic shielding structure according to claim 15, wherein: the specific steps for processing the closed-loop blind slot are,

or, firstly, thinning and browning the surface layer of the precast slab, then punching or cutting and closing by using carbon dioxide laser to form the closed-loop blind groove until the bottom of the closed-loop blind groove is a target layer;

17. A method for manufacturing a circuit board having an electromagnetic shielding structure according to claim 16, wherein: a middle closed-loop metal shielding layer with a preset width is embedded in the middle circuit board layer and positioned around the conducting circuit;

the prefabricated plate surface layer is the upper metal shielding layer or the lower metal shielding layer or the interlayer electric insulation layer surface, and the target layer is the lower metal shielding layer or the upper metal shielding layer or the middle closed-loop metal shielding layer.

18. A method for manufacturing a circuit board with an electromagnetic shielding structure according to any one of claims 14 to 17, wherein: the method also comprises a step of manufacturing a signal circuit for the conductive circuit, wherein the signal circuit comprises a signal input circuit or/and a signal output circuit;

the specific steps for fabricating the signal lines are,