TW202007243A - Printed circuit board and method for manufacturing the same - Google Patents

Abstract

A printed circuit board, the printed circuit board includes a first circuit substrate, a second circuit substrate, and at least one resistive element. The first circuit substrate includes at least one first conductive circuit layer. The first conductive circuit layer includes at least one first conductive circuit. The second circuit substrate includes at least one second conductive circuit layer. The second conductive circuit layer includes at least one second conductive circuit. The resistive element is formed between the first conductive circuit layer and the second conductive circuit layer. One end of the resistive element is bonded and electrically connected to the first conductive circuit, and the other end is bonded and electrically connected to the second conductive circuit. The disclosure also provides a method for manufacturing the printed circuit board.

Description

Circuit board and manufacturing method of circuit board

The invention relates to the field of circuit board manufacturing, in particular to a circuit board containing a resistance element and a method of manufacturing the circuit board.

With the development of resistive elements to miniaturization, embedded technology came into being. It has the following advantages: reduction of packaging area and low power consumption, improvement of signal quality, reduction of electromagnetic interference noise and stabilization of high-frequency power supply.

The embedded passive components commonly used in the embedded technology mainly include: inductive components, capacitive components and resistive components.

For example, the common practice of buried resistance elements is: first bury the resistance element in the same conductive circuit layer, and then add layers, the process is complicated; and the resistance element material mostly uses alloy layers such as NiCr and NiP, but these materials are usually Material vendors control, resulting in higher manufacturing costs of circuit boards with embedded resistance elements.

In view of this, the present invention provides a low-cost circuit board and a method for manufacturing the circuit board.

A circuit board includes a first circuit substrate, a second circuit substrate, and at least one resistive element; the first circuit substrate includes at least a first conductive circuit layer, and the first conductive circuit layer includes at least a first Conductive circuit, the second circuit substrate includes at least one second conductive circuit layer, the second conductive circuit layer includes at least one second conductive circuit, the resistance element is formed between the first conductive circuit layer and the second conductive circuit layer At one time, one end of the resistive element is attached and electrically connected to the first conductive circuit, and the other end is attached and electrically connected to the second conductive circuit.

Further, the first conductive circuit includes a first side perpendicular to the extending direction of the first circuit substrate, the second conductive circuit includes a second side perpendicular to the extending direction of the second circuit substrate, and the resistance elements are respectively The first side and the second side are attached and electrically connected.

Further, the first conductive circuit further includes a first surface vertically connected to the first side surface, the second conductive circuit further includes a second surface vertically connected to the second side surface, the resistance element and the first surface At least one of the surface and the second surface is attached and electrically connected.

Further, a first gap is formed between at least one surface of the resistance element opposite to the first side and the first conductive circuit of the first conductive circuit layer, and at least one of the resistance element is opposite to the second side A second gap is formed between the surface of the back and the second conductive circuit of the second conductive circuit layer; the first circuit substrate and the second circuit substrate are bonded together by an adhesive layer, and the adhesive layer is stacked on the The first conductive circuit layer and the second conductive circuit layer are filled between the first gap and the second gap.

Further, the resistance element is made of a resistance material, the resistance material is a thermosetting colloid, the resistance material is mainly composed of resin, hardener, catalyst and conductive filler, in the resistance material, the resin accounts for The weight percentage is 19.5~35%, the weight percentage of the hardener is 10-17%, the weight percentage of the catalyst is 0~1%, the weight percentage of the conductive filler is 46~69%, The resin is composed of one or more of epoxy resin, dimer acid modified polyester and polypropylene glycol diglycidyl ether.

Further, the colloid also contains an additive, and the weight percentage of the additive is 0.2-2%.

A method for manufacturing a circuit board includes the following steps: providing a first circuit substrate intermediate and a second circuit substrate intermediate; the first circuit substrate intermediate includes a first conductive circuit layer, the first conductive circuit layer At least one first conductive circuit is included; the second circuit substrate intermediate includes a second conductive circuit layer, the second conductive circuit layer includes at least one second conductive circuit; an adhesive layer is provided, and the adhesive is laminated on On the second conductive circuit layer, the adhesive layer includes a first through-groove; providing a resistive material and printing the resistive material in the first through-groove, so that the resistive material is in contact with the second conductive circuit and Electrical connection; and pressing the first circuit board intermediate body on the second circuit board intermediate body, and making the resistive material and the first conductive circuit fit and electrically connected.

Further, the first conductive circuit includes a first side perpendicular to the extending direction of the first circuit substrate, the second conductive circuit includes a second side perpendicular to the extending direction of the second circuit substrate, and the resistance elements are respectively The first side and the second side are attached and electrically connected.

Further, the first conductive circuit further includes a first surface vertically connected to the first side surface, the second conductive circuit further includes a second surface vertically connected to the second side surface, the resistance element and the first surface At least one of the surface and the second surface is attached and electrically connected.

Further, a first gap is formed between at least one surface of the resistance element opposite to the first side and the first conductive circuit of the first conductive circuit layer, and at least one of the resistance element is opposite to the second side A second gap is formed between the surface of the back and the second conductive circuit of the second conductive circuit layer; the adhesive layer is filled in the first gap and the second gap.

Compared with the prior art, the manufacturing cost of the resistance material provided by the present invention is low. In addition, the circuit board and the manufacturing method provided by the present invention adopt the above-mentioned resistive material as the manufacturing material of the resistive element, and the resistive element can be formed in the middle of two circuit substrate intermediates by printing, and cured and formed during the build-up process , Can simplify the process.

In order to further illustrate the technical means and effects of the present invention to achieve the intended purpose of the invention, the specific implementation, structure, features and the circuit board and manufacturing method provided by the present invention are described below in conjunction with the accompanying drawings 1-13 and preferred embodiments. The function is explained in detail as follows.

Please refer to FIG. 1, a first embodiment of the present invention provides a circuit board 100 including a resistance element 31. The circuit board 100 includes a first circuit substrate 70, a second circuit substrate 80, a resistance element 31 and an adhesive layer 41. The first circuit substrate 70 and the second circuit substrate 80 are bonded together by the adhesive layer 41, and the resistance element 31 is located between the first circuit substrate 70 and the second circuit substrate 80.

The first circuit substrate 70 includes an insulating first substrate layer 11, first conductive circuit layer 14 and third conductive circuit layer 16 formed on opposite surfaces of the first substrate layer 11 and formed on the The first solder resist layer 17 on the surface of the third conductive circuit layer 16 away from the first substrate layer 11.

The material of the first substrate layer 11 can generally be selected from polyimide (PI), polyethylene terephthalate (Polyethylene Terephthalate, PET) or polyethylene naphthalate (Polyethylene Naphthalate, PEN), polyethylene (PE), Teflon, liquid crystal polymer (LCP), polyvinyl chloride polymer (PVC) and other flexible materials . It may also be one of rigid supporting materials such as resin plates and ceramic plates.

The first conductive circuit layer 14 includes at least one first conductive circuit 141. Each first conductive line 141 includes a first surface 1411 parallel to the extending direction of the first circuit substrate 70 and a first side surface 1412 perpendicularly connected to the first surface 1411. The first surface 1411 is away from the first substrate layer 11.

The second circuit substrate 80 includes an insulating second substrate layer 21, second conductive circuit layers 24 and fourth conductive circuit layers 26 formed on opposite surfaces of the second substrate layer 21, and formed on the The second solder resist layer 27 on the surface of the fourth conductive circuit layer 26 away from the second substrate layer 21. The second conductive circuit layer 24 is opposite to the first conductive circuit layer 14.

The material of the second substrate layer 21 can generally be selected from polyimide (PI), polyethylene terephthalate (Polyethylene Terephthalate, PET) or polyethylene naphthalate (Polyethylene Naphthalate, PEN), polyethylene (PE), Teflon, liquid crystal polymer (LCP), polyvinyl chloride polymer (PVC) and other flexible materials . It may also be one of rigid supporting materials such as resin plates and ceramic plates.

The second conductive circuit layer 24 includes at least one second conductive circuit 241. Each second conductive line 241 includes a second surface 2411 parallel to the extending direction of the second circuit substrate 80 and a second side surface 2412 perpendicularly connected to the second surface 2411. The second surface 2411 is away from the second substrate layer 21.

The resistance element 31 is obtained by heating, pressing and curing the resistance material 30.

The resistance material 30 is a thermosetting colloid. The resistance material 30 is mainly formed by stirring and mixing resin, hardener, catalyst, conductive filler and additives.

In the resistance material 30, the weight percentage of the resin is 19.5 to 35%, the weight percentage of the hardener is 10 to 17%, and the weight percentage of the catalyst is 0 to 1%, the conductive The weight percentage of the filler is 46~69%, and the weight percentage of the additive is 0.2~2%.

；該聚丙二醇二縮水甘油基醚的結構式為：

。The resin may be a single resin or a mixture of multiple resins. In this embodiment, the resin includes epoxy resin, dimer acid modified polyester, and polypropylene glycol diglycidyl ether. Among them, the structural formula of the epoxy resin is:

; The structural formula of the polypropylene glycol diglycidyl ether is:

.

The hardener may be a conventional hardener such as a fatty amine curing agent, a polyamide curing agent, an alicyclic amine curing agent. In this embodiment, the hardener is a polyamide curing agent.

。The catalyst may be imidazole. In this embodiment, the catalyst is preferably 2-undecylimidazole, and the chemical formula of the 2-undecylimidazole is

.

The conductive filler may be one or more of copper particles coated with silver powder, gold powder, nickel powder and the like.

In this embodiment, the conductive filler is preferably copper particles coated with silver powder on the surface, that is, silver-coated copper powder.

The additive may be a silane tackifier, an organic polymer type anti-settling agent, etc.

。In this embodiment, the additive is a silane tackifier, and its chemical formula is:

.

The resistance element 31 is located between the first conductive circuit layer 14 and the second conductive circuit layer 24.

In this embodiment, the resistance element 31 is respectively connected to the first surface 1411 of the first conductive line 141 and the first side surface 1412 and the second surface 2411 of the second conductive line 241 of the second conductive circuit layer 24 2. The second side 2412 is attached and electrically connected. A first gap 148 is formed between at least one surface of the resistance element 31 opposite to the first side surface 1412 and the first conductive line 141 of the first conductive circuit layer 14, at least one of the resistance element 31 and the first A second gap 248 is formed between the surface opposite to the two side surfaces 2412 and the second conductive circuit 241 of the second conductive circuit layer 24.

Since the resistance element 31 is in contact with and electrically connected to the first surface 1411 and the second surface 2411, the resistance element 31 partially covers the first conductive line 141 and the second conductive line 241, which can increase the resistance element 31 and the contact area between the first circuit substrate 70 and the second circuit substrate 80, thereby enhancing the bonding force between the resistance element 31 and the first conductive circuit layer 14 and the second conductive circuit layer 24, preventing The resistance element 31 is peeled from between the first conductive circuit layer 14 and the second conductive circuit layer 24.

The adhesive layer 41 is stacked between the first conductive circuit layer 14 and the second conductive circuit layer 24 and fills the first gap 148 and the second gap 248.

The circuit board 100 further includes at least one conductive via 60 penetrating through the circuit board 100, the conductive via 60 electrically connecting the third conductive circuit layer 16, the first conductive circuit layer 14, the second conductive circuit layer 24 and The fourth conductive circuit layer 26. The first solder mask 17 and the second solder mask 27 are also filled in the conductive via 60.

1-12, the present invention provides a method for manufacturing a circuit board 100 including a resistive element 31, the steps are as follows:

The first step, please refer to FIGS. 2-8, provides a first circuit substrate intermediate 71, a glue layer 41 and a second circuit substrate intermediate 81.

Specifically, please refer to FIGS. 3 to 4, the manufacturing method of the first circuit board intermediate body 71 includes the following steps:

First, referring to FIG. 3, a first copper-clad substrate 10 is provided. The first copper-clad substrate 10 includes an insulating first substrate layer 11 formed on opposite surfaces of the first substrate layer 11 The first copper foil layer 12 and the second copper foil layer 13.

Next, referring to FIG. 4, the first copper foil layer 12 is formed to form a first conductive circuit layer 14, and then the first circuit board intermediate body 71 is formed.

Specifically, the first conductive circuit layer 14 is manufactured through an image transfer process.

The first conductive circuit layer 14 includes at least one first conductive circuit 141. Each first conductive line 141 includes a first surface 1411 parallel to the extending direction of the first circuit substrate intermediate body 71 and a first side surface 1412 perpendicularly connected to the first surface 1411. The first surface 1411 is away from the first substrate layer 11.

Please refer to FIGS. 5-6. The manufacturing method of the second circuit substrate intermediate 81 includes the following steps:

First, please refer to FIG. 5, a second copper-clad substrate 20 is provided. The second copper-clad substrate 20 includes an insulating second substrate layer 21 formed on opposite surfaces of the second substrate layer 21. The third copper foil layer 22 and the fourth copper foil layer 23.

Next, referring to FIG. 6, the third copper foil layer 22 is formed to form a second conductive circuit layer 24, and then the second circuit substrate intermediate 81 is formed.

Specifically, the second conductive circuit layer 24 is manufactured through an image transfer process.

The second conductive circuit layer 24 includes at least one second conductive circuit 241. Each second conductive line 241 includes a second surface 2411 parallel to the extending direction of the second circuit substrate 80 and a second side surface 2412 perpendicularly connected to the second surface 2411. The second surface 2411 is away from the second substrate layer 21.

Please refer to FIGS. 7-8. The manufacturing method of the adhesive layer 41 includes the following steps:

First, referring to FIG. 7, a film 40 is provided.

Next, referring to FIG. 8, a first through-groove 414 penetrating the film 40 is formed on the film 40 to form the adhesive layer 41.

Specifically, the first through groove 414 may be formed by punching.

In the second step, please refer to FIG. 9, the adhesive layer 41 is pressed onto the second conductive circuit layer 24 first, and a resistive material 30 is provided. The resistive material 30 is printed on the conductive layer of the second conductive circuit layer 24 In the circuit gap, the resistance material 30 penetrates the first through slot 414.

In this embodiment, the resistive material 30 protrudes from the adhesive layer 41. In other embodiments, the resistive material 30 can also be flush with the adhesive layer 41.

Specifically, the resistive material 30 is a thermosetting colloid. The resistive material 30 is attached to and electrically connected to the second surface 2411 and the second side surface 2412 of the second conductive circuit 241 of the second conductive circuit layer 24. A second gap 248 is formed between at least one surface of the resistive material 30 opposite to the second side surface 2412 and the second conductive circuit 241 of the second conductive circuit layer 24, during the process of pressing the adhesive layer 41 The adhesive layer 41 is filled in the second gap 248.

The resistance material 30 is used to manufacture the resistance element 31.

The resistance material 30 is a thermosetting colloid. The resistance material 30 is mainly formed by stirring and mixing resin, hardener, catalyst, conductive filler and additives.

In the resistance material 30, the weight percentage of the resin is 19.5 to 35%, the weight percentage of the hardener is 10 to 17%, and the weight percentage of the catalyst is 0 to 1%, the conductive The weight percentage of the filler is 46~69%, and the weight percentage of the additive is 0.2~2%.

The resin may be a single resin or a mixture of multiple resins.

；該聚丙二醇二縮水甘油基醚的結構式為：

。In this embodiment, the resin includes epoxy resin, dimer acid modified polyester, and polypropylene glycol diglycidyl ether. Among them, the structural formula of the epoxy resin is:

; The structural formula of the polypropylene glycol diglycidyl ether is:

.

The hardener may be a conventional hardener such as a fatty amine curing agent, a polyamide curing agent, an alicyclic amine curing agent.

The catalyst may be imidazole.

。In this embodiment, the catalyst is preferably 2-undecylimidazole, and the chemical formula of the 2-undecylimidazole is

.

The conductive filler may be one or more of copper particles coated with silver powder, gold powder, nickel powder and the like.

In this embodiment, the conductive filler is preferably copper particles coated with silver powder on the surface, that is, silver-coated copper powder.

The additive may be a silane tackifier, an organic polymer type anti-settling agent, etc.

。In this embodiment, the additive is a silane tackifier, and its chemical formula is:

.

In the third step, please refer to FIG. 10, the first circuit board intermediate body 71 is overlaid on the second circuit board intermediate body 81, and heat and pressure are applied to make the second circuit board intermediate body 81 and the first circuit The substrate intermediate bodies 71 are bonded together.

Wherein, the resistive material 30 is attached to and electrically connected to the first surface 1411 and the first side 1412 of the first conductive line 141, and at least one surface of the resistive material 30 opposite to the first side 1412 and the A first gap 148 is formed between the first conductive lines 141 of the first conductive line layer 14, and the adhesive layer 41 is filled into the first gap 148 during the heating and pressing process.

In addition, during the heating and pressurizing process, the resistance material 30 is cured and formed, and the resistance material 30 after curing and molding is the resistance element 31.

Since the resistance element 31 is located between the first circuit board intermediate body 71 and the second circuit board intermediate body 81, the thickness of the resistance element 31 can be controlled by adjusting the thickness of the adhesive layer 41, and then the resistance element 31 can be controlled The size of the cross-sectional area of the cross-section in the thickness direction is to change the size of the resistance value of the resistance element 31 when the resistivity and the length of the resistance remain unchanged.

In the fourth step, please refer to FIG. 11, at least one conductive via 60 is formed on the first circuit substrate intermediate body 71 and the second circuit substrate intermediate body 81 after being pressed.

The conductive via 60 is electrically connected to the first conductive circuit layer 14, the second conductive circuit layer 24, the second copper foil layer 13 and the fourth copper foil layer 23.

Specifically, at least one through hole may be formed by laser etching or mechanical drilling, and then a plating layer is formed on the wall of the through hole by electroplating, and then the conductive through hole 60 is formed.

In the fifth step, referring to FIG. 12, the second copper foil layer 13 and the fourth copper foil layer 23 are respectively formed to form a third conductive circuit layer 16 and a fourth conductive circuit layer 26.

The conductive via 60 is electrically connected to the first conductive circuit layer 14, the second conductive circuit layer 24, the third conductive circuit layer 16 and the fourth conductive circuit layer 26.

Sixth step, please refer to FIG. 1, a first solder resist layer 17 is formed on the surface of the third conductive circuit layer 16 away from the first substrate layer 11, and the fourth conductive circuit layer 26 is away from the first A second solder resist layer 27 is formed on the surface of the two substrate layers 21, and the first solder resist layer 17 and the second solder resist layer 27 are filled in the conductive via 60 to form the circuit board 100.

Referring to FIG. 13, a second embodiment of the present invention provides a circuit board 200. The structure of the circuit board 200 and the circuit board 100 are basically the same. The difference is that the resistance element 31 does not cover the first conductive circuit 141 and The second conductive line 241. That is, the resistance element 31 is only attached to and electrically connected to the first side surface 1412 and the second side surface 2412, and is not attached to and electrically connected to the first surface 1411 and the second surface 2411.

Of course, the resistance element 31 may only cover one of the first conductive line 141 and the second conductive line 241.

Compared with the prior art, the manufacturing cost of the resistance material provided by the present invention is low.

In addition, the circuit board and the manufacturing method provided by the present invention adopt the above-mentioned resistive material as the manufacturing material of the resistive element, and the resistive element can be formed in the middle of two circuit substrate intermediates by printing, and cured and formed during the build-up process , Can simplify the process.

The above is only the preferred embodiment of the present invention, and does not limit the present invention in any form. Although the present invention has been disclosed as the preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art , Without departing from the scope of the technical solutions of the present invention, when the technical contents disclosed above can be used to make some changes or modifications to equivalent equivalent implementations, but without departing from the technical solutions of the present invention, the technical essence of the present invention Any simple modifications, equivalent changes and modifications made to the above embodiments still fall within the scope of the technical solution of the present invention.

100, 200‧‧‧ circuit board 10‧‧‧The first copper clad substrate 11‧‧‧First substrate layer 12‧‧‧The first copper foil layer 13‧‧‧Second copper foil layer 14‧‧‧ First conductive circuit layer 141‧‧‧The first conductive circuit 1411‧‧‧First surface 1412‧‧‧First side 148‧‧‧ First gap 20‧‧‧Second copper-clad substrate 21‧‧‧Second substrate layer 22‧‧‧The third copper foil layer 23‧‧‧Fourth copper foil layer 24‧‧‧Second conductive circuit layer 241‧‧‧Second Conducting Circuit 2411‧‧‧Second surface 2412‧‧‧Second side 248‧‧‧Second gap 30‧‧‧Resistance material 31‧‧‧Resistance element 40‧‧‧film 41‧‧‧adhesive layer 414‧‧‧The first slot 60‧‧‧conductive through hole 16‧‧‧The third conductive circuit layer 17‧‧‧First solder mask 26‧‧‧The fourth conductive circuit layer 27‧‧‧Second solder mask 70‧‧‧ First circuit board 71‧‧‧ First circuit board intermediate 80‧‧‧ Second circuit board 81‧‧‧Intermediate of the second circuit board

FIG. 1 is a cross-sectional view of a circuit board provided by a first embodiment of the present invention.

2 is a cross-sectional view of a first circuit substrate intermediate body, an adhesive layer, and a second circuit substrate intermediate body provided by the first embodiment of the present invention.

3 is a cross-sectional view of a first copper-clad substrate provided by the present invention.

4 is a cross-sectional view of forming a first conductive circuit layer by forming one copper foil layer of the first copper-clad substrate shown in FIG. 3 to form an intermediate body of the first circuit substrate shown in FIG. 2.

5 is a cross-sectional view of a second copper-clad substrate provided by the first embodiment of the present invention.

6 is a cross-sectional view of forming a second conductive circuit layer by forming one copper foil layer of the second copper-clad substrate shown in FIG. 5 and further obtaining the intermediate body of the second circuit substrate shown in FIG. 2.

7 is a cross-sectional view of a film provided by the first embodiment of the present invention.

8 is a cross-sectional view of forming the film shown in FIG. 7 to form the adhesive layer shown in FIG. 2.

FIG. 9 is to laminate the glue shown in FIG. 2 on the second conductive circuit layer shown in FIG. 6 and provide a glue for making a resistor, and the glue is formed on the intermediate of the first circuit substrate and the second circuit Cross-sectional view between substrate intermediates.

10 is a cross-sectional view of the first circuit board intermediate body of FIG. 2 formed on the second circuit board intermediate body and heated and pressurized.

FIG. 11 is a cross-sectional view after forming conductive vias in the first circuit board intermediate body and the second circuit board intermediate body shown in FIG. 10.

12 is a cross-sectional view of the second copper foil layer shown in FIG. 3 and the fourth copper foil layer shown in FIG. 5 after forming a third conductive circuit layer and a fourth conductive circuit layer, respectively.

13 is a cross-sectional view of a circuit board provided by a second embodiment of the present invention.

100‧‧‧ circuit board

11‧‧‧First substrate layer

14‧‧‧ First conductive circuit layer

141‧‧‧The first conductive circuit

1411‧‧‧First surface

1412‧‧‧First side

148‧‧‧ First gap

24‧‧‧Second conductive circuit layer

241‧‧‧Second Conducting Circuit

2411‧‧‧Second surface

2412‧‧‧Second side

248‧‧‧Second gap

31‧‧‧Resistance element

41‧‧‧adhesive layer

414‧‧‧The first slot

60‧‧‧conductive through hole

16‧‧‧The third conductive circuit layer

17‧‧‧First solder mask

26‧‧‧The fourth conductive circuit layer

27‧‧‧Second solder mask

70‧‧‧ First circuit board

80‧‧‧ Second circuit board

Claims (10)

A circuit board includes a first circuit substrate, a second circuit substrate, and at least one resistive element; the first circuit substrate includes at least a first conductive circuit layer, and the first conductive circuit layer includes at least a first Conductive circuit, the second circuit substrate includes at least one second conductive circuit layer, the second conductive circuit layer includes at least one second conductive circuit, wherein the resistance element is formed on the first conductive circuit layer and the second conductive circuit Between the layers, one end of the resistance element is attached and electrically connected to the first conductive circuit, and the other end is attached and electrically connected to the second conductive circuit. The circuit board according to claim 1, wherein the first conductive circuit includes a first side perpendicular to the extending direction of the first circuit substrate, and the second conductive circuit includes a perpendicular to the second circuit substrate In the second side of the direction, the resistance element is attached to and electrically connected to the first side and the second side, respectively. The circuit board according to claim 2, wherein the first conductive circuit further includes a first surface vertically connected to the first side surface, and the second conductive circuit further includes a vertically connected surface to the second side surface On the second surface, the resistance element is attached to and electrically connected to at least one of the first surface and the second surface. The circuit board according to claim 2, wherein a first gap is formed between at least one surface of the resistance element opposite to the first side surface and the first conductive circuit of the first conductive circuit layer, the A second gap is formed between at least one surface of the resistance element opposite to the second side and the second conductive circuit of the second conductive circuit layer; the first circuit substrate and the second circuit substrate are adhered by an adhesive layer Together, the glue layer is stacked between the first conductive circuit layer and the second conductive circuit layer and filled in the first gap and the second gap. The circuit board according to claim 1, wherein the resistive element is made of a resistive material, the resistive material is a thermosetting colloid, the resistive material is mainly composed of resin, hardener, catalyst and conductive filler, In the resistance material, the weight percentage of the resin is 19.5 to 35%, the weight percentage of the hardener is 10 to 17%, the weight percentage of the catalyst is 0 to 1%, the conductive filler The weight percentage is 46~69%, the resin is composed of one or more of epoxy resin, dimer acid modified polyester and polypropylene glycol diglycidyl ether. The circuit board according to claim 5, wherein the resistive material further contains an additive, and the weight percentage of the additive is 0.2-2%. A method for manufacturing a circuit board includes the following steps: providing a first circuit substrate intermediate and a second circuit substrate intermediate; the first circuit substrate intermediate includes a first conductive circuit layer and the first conductive circuit layer At least one first conductive circuit is included; the second circuit substrate intermediate includes a second conductive circuit layer, the second conductive circuit layer includes at least one second conductive circuit; an adhesive layer is provided, and the adhesive is laminated on On the second conductive circuit layer, the adhesive layer includes a first through slot; providing a resistive material and printing the resistive material in the first through slot to form a resistive element, one end of the resistive element and the second The conductive circuits are attached and electrically connected; and the first circuit substrate intermediate is pressed onto the second circuit substrate intermediate, and the other end of the resistance element is attached and electrically connected to the first conductive circuit Sexual connection. The method of manufacturing a circuit board according to claim 7, wherein the first conductive circuit includes a first side perpendicular to the extending direction of the first circuit substrate, and the second conductive circuit includes a perpendicular to the second On the second side surface of the circuit board in the extending direction, the resistance element is respectively attached to and electrically connected to the first side surface and the second side surface. The method for manufacturing a circuit board according to claim 8, wherein the first conductive circuit further includes a first surface perpendicularly connected to the first side surface, and the second conductive circuit further includes a second surface On the vertically connected second surface, the resistance element is in close contact with and electrically connected to at least one of the first surface and the second surface. The method for manufacturing a circuit board according to claim 8, wherein at least one surface of the resistance element opposite to the first side surface and the first conductive circuit of the first conductive circuit layer are formed with a first A gap, a second gap is formed between at least one surface of the resistance element opposite to the second side and the second conductive circuit of the second conductive circuit layer; the adhesive layer is filled in the first gap and the second Within the gap.

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