阅读说明：本技术 电路板的制造方法及电路板 (Circuit board manufacturing method and circuit board ) 是由 袁刚 杨梅 李成佳 于 2019-08-27 设计创作，主要内容包括：一种电路板的制造方法,包括步骤：提供一内层线路基板,所述内层线路基板包括一绝缘基材以及一设置于所述绝缘基材上的第一导电线路层,所述第一导电线路层包括第一线路部分及围绕所述第一线路部分设置的第二线路部分。在所述第一线路部分上压合一第一覆盖膜,并使得所述第二线路部分暴露于所述第一覆盖膜且所述第一覆盖膜和所述第二线路部分共同形成第一台阶部。在所述第一覆盖膜上形成一第一屏蔽膜且至少在所述第一台阶部的表面和所述第一屏蔽膜的侧壁形成一第一金属层,从而获得所述电路板。另,本发明还提供一种电路板。本发明提供的电路板可有效引导静电放电电流,避免了静电电流损害该电路板。(A method of manufacturing a circuit board, comprising the steps of: providing an inner layer circuit substrate, wherein the inner layer circuit substrate comprises an insulating base material and a first conductive circuit layer arranged on the insulating base material, and the first conductive circuit layer comprises a first circuit part and a second circuit part arranged around the first circuit part. A first cover film is pressed on the first circuit portion, the second circuit portion is exposed to the first cover film, and the first cover film and the second circuit portion jointly form a first step portion. And forming a first shielding film on the first covering film, and forming a first metal layer on at least the surface of the first step part and the side wall of the first shielding film, thereby obtaining the circuit board. In addition, the invention also provides a circuit board. The circuit board provided by the invention can effectively guide the electrostatic discharge current and avoid the electrostatic discharge current from damaging the circuit board.)

1. A method of manufacturing a circuit board, comprising the steps of:

providing an inner layer circuit substrate, wherein the inner layer circuit substrate comprises an insulating base material and a first conductive circuit layer arranged on the insulating base material, and the first conductive circuit layer comprises a first circuit part and a second circuit part arranged around the first circuit part;

pressing a first cover film on the first circuit part, and exposing the second circuit part to the first cover film to form a first step part together with the first cover film and the second circuit part;

forming a first shielding film on the first cover film;

and forming a first metal layer on at least the surface of the first step part and the side wall of the first shielding film, thereby obtaining the circuit board.

2. The manufacturing method according to claim 1, wherein the inner-layer wiring substrate further includes a second conductive wiring line layer provided on the other side of the insulating base material opposite to the first conductive wiring line layer, the first conductive wiring line layer being electrically connected to the second conductive wiring line layer, the second conductive wiring line layer including a third wiring line portion and a fourth wiring line portion surrounding the third wiring line portion, the third wiring line portion corresponding to the first wiring line portion, the fourth wiring line portion corresponding to the second wiring line portion, the method further comprising:

pressing a second cover film on the third line portion so that the fourth line portion is exposed to the second cover film and the fourth line portion together form a second stepped portion;

pressing a second shielding film on the second covering film; and

and forming a second metal layer on at least the surface of the second step part and the side wall of the second shielding film.

3. The manufacturing method according to claim 2, wherein the first circuit portion includes a pad area and a non-pad area other than the pad area, the first cover film has an opening at a position corresponding to the pad area, the first cover film includes a first cover portion disposed around the opening and a second cover portion disposed around the first cover portion, the first shielding film is formed on the first cover portion, the second cover portion is exposed to the first shielding film, the first shielding film and the second cover portion together form a third step portion, and the first metal layer further covers a surface of the third step portion and a part of a surface of the first shielding film.

4. The manufacturing method according to claim 3, wherein the second cover film includes a third cover portion and a fourth cover portion provided around the third cover portion, the third cover portion corresponds to the opening and the first cover portion, the fourth cover portion corresponds to the second cover portion, the second shielding film is formed on the third cover portion, the fourth cover portion is exposed to the second shielding film and the fourth cover portion collectively form a fourth stepped portion, and the second metal layer further covers a surface of the fourth stepped portion and a part of a surface of the second shielding film.

5. The method of manufacturing of claim 3, wherein prior to forming the first metal layer, the method further comprises:

covering a mask on the first shielding film, wherein the mask is filled in the opening and used for exposing at least the second covering part, thereby obtaining an intermediate body;

and electroplating the surface of the intermediate except the mask region to form the first metal layer.

6. The method for manufacturing a circuit board according to claim 1, wherein the first metal layer includes a copper-plated layer and a gold-plated layer provided on the copper-plated layer.

7. The method for manufacturing a circuit board according to claim 1, wherein the first cover film includes a first adhesive layer and a first insulating layer, the first adhesive layer is disposed between the first conductive trace layer and the first insulating layer, and the first adhesive layer fills gaps between the first conductive trace layers.

8. The method of manufacturing a circuit board according to claim 7, wherein the first shielding film includes a second adhesive layer formed on the first insulating layer, an electromagnetic shielding layer formed on the second adhesive layer, and a second insulating layer formed on the electromagnetic shielding layer.

9. A circuit board is characterized by comprising an inner layer circuit substrate, wherein the inner layer circuit substrate comprises an insulating base material and a first conductive circuit layer arranged on the insulating base material, and the first conductive circuit layer comprises a first circuit part and a second circuit part arranged around the first circuit part;

a first cover film is arranged on the first circuit part, the second circuit part is exposed to the first cover film, and the first cover film and the second circuit part jointly form a first step part;

a first shielding film is arranged on the first covering film;

a first metal layer is disposed on at least a surface of the first step portion and a sidewall of the first shielding film.

10. The circuit board of claim 9, wherein the inner-layer wiring substrate further comprises a second conductive wiring line layer provided on the other side of the insulating substrate opposite to the first conductive wiring line layer, the first conductive wiring line layer being electrically connected to the second conductive wiring line layer, the second conductive wiring line layer including a third wiring line portion and a fourth wiring line portion surrounding the third wiring line portion, the third wiring line portion corresponding to the first wiring line portion, the fourth wiring line portion corresponding to the second wiring line portion;

a second cover film is arranged on the third circuit part, the fourth circuit part is exposed to the second cover film, and the second cover film and the fourth circuit part jointly form a second step part;

a second shielding film is arranged on the second covering film;

and a second metal layer is arranged on at least the surface of the second step part and the side wall of the second shielding film.

Technical Field

The invention relates to a circuit board and a manufacturing method thereof.

Background

Electrostatic Discharge (ESD) is a phenomenon in which, when the field strength around a charged body exceeds the dielectric breakdown field strength of the surrounding medium, the medium is ionized, and the electrostatic charge on the charged body is partially or completely eliminated.

Under the development trend of light, thin, short and small PCB, the circuit of the integrated circuit is reduced, the voltage resistance is reduced, the area of the circuit is reduced, the ESD resistance of the PCB is weakened, and meanwhile, the probability of generating static electricity is greatly increased due to the common application of a large amount of high-insulation materials such as plastic products and the like, and the damage is caused to the circuit board.

Disclosure of Invention

Accordingly, there is a need for a circuit board to solve the problem of weak electrostatic discharge resistance.

In addition, it is necessary to provide a method for manufacturing a circuit board.

A method of manufacturing a circuit board, comprising the steps of:

providing an inner layer circuit substrate, wherein the inner layer circuit substrate comprises an insulating base material and a first conductive circuit layer arranged on the insulating base material, and the first conductive circuit layer comprises a first circuit part and a second circuit part arranged around the first circuit part.

A first cover film is pressed on the first circuit portion, the second circuit portion is exposed to the first cover film, and the first cover film and the second circuit portion jointly form a first step portion.

And forming a first shielding film on the first covering film, and forming a first metal layer on at least the surface of the first step part and the side wall of the first shielding film, thereby obtaining the circuit board.

Further, the inner-layer circuit substrate further includes a second conductive circuit layer disposed on the other side of the insulating base material opposite to the first conductive circuit layer, the first conductive circuit layer is electrically connected to the second conductive circuit layer, the second conductive circuit layer includes a third circuit portion and a fourth circuit portion surrounding the third circuit portion, the third circuit portion corresponds to the first circuit portion, the fourth circuit portion corresponds to the second circuit portion, and the method further includes:

a second cover film is pressed on the third line portion so that the fourth line portion is exposed to the second cover film and the fourth line portion collectively form a second stepped portion.

And pressing a second shielding film on the second covering film, and forming a second metal layer on at least the surface of the second step part and the side wall of the second shielding film.

Further, the first circuit portion includes a pad area and a non-pad area except the pad area, an opening is opened at a position of the first cover film corresponding to the pad area, the first cover film includes a first cover portion disposed around the opening and a second cover portion disposed around the first cover portion, the first shielding film is formed on the first cover portion, the second cover portion is exposed to the first shielding film, the first shielding film and the second cover portion together form a third step portion, and the first metal layer further covers a surface of the third step portion and a partial surface of the first shielding film.

Further, the second cover film includes a third cover portion and a fourth cover portion disposed around the third cover portion, the third cover portion corresponds to the opening and the first cover portion, the fourth cover portion corresponds to the second cover portion, the second shielding film is formed on the third cover portion, the fourth cover portion is exposed to the second shielding film, the second shielding film and the fourth cover portion jointly form a fourth stepped portion, and the second metal layer further covers a surface of the fourth stepped portion and a partial surface of the second shielding film.

Further, before forming the first metal layer, the method further includes:

and covering a mask on the first shielding film, wherein the mask is filled in the opening and used for exposing at least the second covering part, thereby obtaining an intermediate body.

And electroplating the surface of the intermediate except the mask region to form the first metal layer.

Further, the first metal layer comprises a copper plating layer and a gold plating layer arranged on the copper plating layer.

Further, the first cover film comprises a first adhesive layer and a first insulating layer, the first adhesive layer is arranged between the first conductive circuit layer and the first insulating layer, and the first adhesive layer fills gaps between the first conductive circuit layer.

Further, the first shielding film includes a second adhesive layer formed on the first insulating layer, an electromagnetic shielding layer formed on the second adhesive layer, and a second insulating layer formed on the electromagnetic shielding layer.

The utility model provides a circuit board, includes inlayer circuit base plate, inlayer circuit base plate includes an insulating substrate and one set up in first conducting wire layer on the insulating substrate, first conducting wire layer includes first circuit part and surrounds the second circuit part that first circuit part set up.

A first cover film is arranged on the first circuit portion, the second circuit portion is exposed to the first cover film, and the first cover film and the second circuit portion jointly form a first step portion. The first cover film is provided with a first shielding film, and a first metal layer is arranged on the surface of the first step part and the side wall of the first shielding film.

Further, the inner-layer circuit substrate further comprises a second conductive circuit layer arranged on the other side, opposite to the first conductive circuit layer, of the insulating base material, the first conductive circuit layer is electrically connected with the second conductive circuit layer, the second conductive circuit layer comprises a third circuit portion and a fourth circuit portion surrounding the third circuit portion, the third circuit portion corresponds to the first circuit portion, and the fourth circuit portion corresponds to the second circuit portion.

The third circuit portion is provided with a second cover film thereon, the fourth circuit portion is exposed to the second cover film and the fourth circuit portion together form a second stepped portion.

The second cover film is provided with a second shielding film, and a second metal layer is arranged on the surface of the second step part and the side wall of the second shielding film.

The circuit board provided by the invention achieves the effect of guiding the electrostatic discharge current by arranging the first metal layer, avoids the electrostatic discharge current from damaging the circuit board, and meanwhile, the first metal layer is arranged on the side wall of the circuit board in a step shape, so that the bonding force between the first metal layer and the side wall of the circuit board can be improved.

Drawings

FIG. 1 is a schematic cross-sectional view of an inner layer circuit board according to the present invention.

Fig. 2 is a schematic cross-sectional view of the inner-layer wiring substrate shown in fig. 1 after being covered with the first cover film.

Fig. 3 is a schematic cross-sectional view of the first shielding film covered by the first cover film shown in fig. 2.

Fig. 4 is a schematic cross-sectional view of the first shielding film shown in fig. 3 after a seed layer and a mask are formed thereon.

Fig. 5 is a schematic diagram of a circuit board provided by the present invention.

Description of the main elements

The following detailed description will further illustrate the invention in conjunction with the above-described figures.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to fig. 1 to 5 in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

Some embodiments of the invention are described in detail below with reference to figures 1-5. Without conflict, the embodiments and features of the embodiments described below may be combined with each other, and the order of the steps in the embodiments described below may be changed.

The method for manufacturing the circuit board 100 provided by the embodiment of the invention comprises the following steps:

s1, providing an inner circuit board 10, referring to fig. 1, where the inner circuit board 10 includes an insulating base 11 and a first conductive trace layer 12 disposed on the insulating base 11, the insulating base 11 may be made of one of Polyimide (PI), Polyethylene Terephthalate (PET), and Polyethylene Naphthalate (PEN), and the first conductive trace layer 12 includes a first circuit portion 121 and a second circuit portion 122 disposed around the first circuit portion 121;

s2, referring to fig. 2, a first cover film 20 is laminated on the first circuit portion 121, and the second circuit portion 122 is exposed to the first cover film 20, and the first cover film 20 and the second circuit portion 122 form a first step portion 21;

s3, referring to fig. 3, forming a first shielding film 30 on the first cover film 20;

s4 referring to fig. 5, a first metal layer 40 is formed on at least the surface of the first step portion 21 and the sidewall of the first shielding film 30, thereby obtaining the circuit board 100.

In this embodiment, referring to fig. 1, in step S1, the inner-layer circuit substrate 10 further includes a second conductive trace layer 13 disposed on the other side of the insulating base material 11 opposite to the first conductive trace layer 12, the first conductive trace layer 12 is electrically connected to the second conductive trace layer 13, the second conductive trace layer 13 includes a third circuit portion 131 and a fourth circuit portion 132 surrounding the third circuit portion 131, the third circuit portion 131 corresponds to the first circuit portion 121, and the fourth circuit portion 132 corresponds to the second circuit portion 122.

In this embodiment, the first conductive trace layer 12 and the second conductive trace layer 13 are electrically connected through a via 14.

In this embodiment, referring to fig. 2, the step S2 further includes: pressing a second cover film 50 on the third circuit portion 131, so that the fourth circuit portion 132 is exposed to the second cover film 50 and the fourth circuit portion 132 together form a second step 51;

referring to fig. 3, the step S3 further includes: a second shielding film 60 is pressed on the second cover film 50.

Referring to fig. 5, the step S4 further includes: a second metal layer 70 is formed on at least the surface of the second stepped portion 51 and the sidewall of the second shielding film 60.

In the present embodiment, referring to fig. 2 and fig. 3, in step S3, the first circuit portion 121 includes a pad area 1211 and a non-pad area 1212 excluding the pad area 1211, and an opening 22 is formed in a position of the first cover film 20 corresponding to the pad area 1211, so that the pad area 1211 is exposed. The pad area 1211 is used for connecting an external electronic component (not shown). The first cover film 20 includes a first cover portion 23 disposed around the opening 22 and a second cover portion 24 disposed around the first cover portion 23, the first shielding film 30 is formed on the first cover portion 23, the second cover portion 24 is exposed to the first shielding film 30, the first shielding film 30 and the second cover portion 24 together form a third step portion 31, and the first metal layer 40 further covers a surface of the third step portion 31 and a part of a surface of the first shielding film 30.

In this embodiment, referring to fig. 3 and fig. 5, the second cover film 50 includes a third cover portion 52 and a fourth cover portion 53 disposed around the third cover portion 52, the third cover portion 52 corresponds to the opening 22 and the first cover portion 23, the fourth cover portion 53 corresponds to the second cover portion 24, the second shielding film 60 is formed on the third cover portion 52, the fourth cover portion 53 is exposed to the second shielding film 60, the second shielding film 60 and the fourth cover portion 53 together form a fourth step portion 61, and the second metal layer 70 further covers a surface of the fourth step portion 61 and a part of a surface of the second shielding film 60.

In this embodiment, referring to fig. 4, after step S3, the method further includes: a first mask 32 and a second mask 62 are respectively covered on the first shielding film 30 and the second shielding film 60, the first mask 32 is filled in the opening 22 and used for exposing at least the second covering portion 24, and the second mask 62 is used for exposing the fourth covering portion 53, so as to obtain an intermediate body 33.

Further, before covering the first mask 32, a seed layer 321 may further cover the first shielding film 30 and the second shielding film 60, where the seed layer 321 is further formed on the surfaces of the first step portion 21 to the fourth step portion 61 and the surface of the pad area 1211.

In this embodiment, referring to fig. 5, step S4 further includes electroplating on the surface of the intermediate body 33 except for the area of the first mask 32, so as to form the first metal layer 40.

In the present embodiment, referring to fig. 5, the first metal layer 40 and the second metal layer 70 each include a copper plating layer 41 and a gold plating layer 42 disposed on the copper plating layer 41.

In the present embodiment, referring to fig. 2 to 5, the first cover film 20 and the second cover film 50 both include a first adhesive layer 25 and a first insulating layer 26, the first adhesive layer 25 is disposed between the first conductive trace layer 12 and the first insulating layer 26, and the first adhesive layer 25 fills a gap between the first conductive trace layers 12. In this embodiment, the material of the first adhesive layer 25 is epoxy resin glue, and the material of the first insulating layer 26 is Polyimide (PI).

In the present embodiment, referring to fig. 3 to fig. 5, each of the first shielding film 30 and the second shielding film 60 includes a second adhesive layer 34 formed on the first insulating layer 26, an electromagnetic shielding layer 35 formed on the second adhesive layer 34, and a second insulating layer 36 formed on the electromagnetic shielding layer 35. In this embodiment, the second adhesive layer 34 is made of anisotropic conductive adhesive, the electromagnetic shielding layer 35 is made of one of copper, silver and conductive paste, and the second insulating layer 36 is made of epoxy resin ink.

The present invention provides a circuit board 100 manufactured by the above manufacturing method, please refer to fig. 1 to 5, wherein the circuit board 100 includes an inner circuit substrate 10, the inner circuit substrate 10 includes an insulating base material 11 and a first conductive circuit layer 12 disposed on the insulating base material 11, and the first conductive circuit layer 12 includes a first circuit portion 121 and a second circuit portion 122 disposed around the first circuit portion 121. The first circuit portion 121 is provided with a first coverlay 20, and the second circuit portion 122 is exposed to the first coverlay 20, and the first coverlay 20 and the second circuit portion 122 together form a first step portion 21. The first cover film 20 is provided with a first shielding film 30, and at least a first metal layer 40 is provided on the surface of the first step portion 21 and the sidewall of the first shielding film 30.

The inner-layer circuit substrate 10 further includes a second conductive circuit layer 13 disposed on the other side of the insulating base material 11 opposite to the first conductive circuit layer 12, the first conductive circuit layer 12 is electrically connected to the second conductive circuit layer 13, the second conductive circuit layer 13 includes a third circuit portion 131 and a fourth circuit portion 132 surrounding the third circuit portion 131, the third circuit portion 131 corresponds to the first circuit portion 121, and the fourth circuit portion 132 corresponds to the second circuit portion 122; a second cover film 50 is disposed on the third circuit portion 131, the fourth circuit portion 132 is exposed to the second cover film 50 and the fourth circuit portion 132 together form a second stepped portion 51; a second shielding film 60 is arranged on the second covering film 50; a second metal layer 70 is disposed on at least a surface of the second stepped portion 51 and a sidewall of the second shielding film 60.

In the present embodiment, the first metal layer 40 and the second metal layer 70 may be electrically connected to a ground line (not shown) of the circuit board 100, so as to effectively attract the electrostatic current and release the electrostatic current to the ground line in time.

In other embodiments of the present invention, the circuit board 100 may be a multi-layer hard board or a multi-layer soft board.

The circuit board provided by the invention achieves the effect of guiding the electrostatic current to discharge by arranging the first metal layer and the second metal layer, so that the circuit board is prevented from being damaged by the electrostatic current, meanwhile, the first metal layer and the second metal layer are arranged on the side wall of the circuit board in a step shape, so that the bonding force between the first metal layer and the side wall of the circuit board and the bonding force between the second metal layer and the side wall of the circuit board can be improved, and meanwhile, the first metal layer or the second metal layer is conveniently externally connected with a grounding wire, so that the electrostatic circuit is guided into an externally connected grounding layer, and the damage to a sensitive circuit caused by the fact that the static close to the edge of the board enters the board along with the.

Although the present invention has been described with reference to the above preferred embodiments, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.