Circuit board with heat dissipation function and manufacturing method thereof

Abstract

The application provides a manufacturing method of a circuit board with heat dissipation function, comprising the following steps: providing a heat dissipation substrate, comprising a phase change structure and a heat conduction layer, wherein the heat conduction layer covers the phase change structure; forming an insulating layer on the surface of the heat dissipation substrate, wherein the insulating layer is provided with a groove; arranging an electronic component in the groove; forming a single-sided copper-clad substrate on the insulating layer, wherein the single-sided copper-clad substrate comprises a base layer and a copper foil layer; forming a second through hole in the single-sided copper-clad substrate and the insulating layer; filling the second through hole with a heat conduction material to form a heat conduction part; electroplating a metal on the copper foil layer to form a copper-plated layer; and etching the copper-plated layer and the copper foil layer to form a conductive circuit layer, thereby obtaining the circuit board. The circuit board manufactured by the manufacturing method has good heat dissipation effect. The application also provides a circuit board manufactured by the manufacturing method.

Description

Technical Field

[0001] The present application relates to the technical field of circuit boards, and in particular to a circuit board with heat dissipation function and a manufacturing method thereof. Background Art

[0002] With the advancement of electronic product technology, circuit boards are moving towards miniaturization and higher density. However, high-power electronic components consume significant power, leading to a dramatic increase in heat flux, generating significant amounts of heat in a short period of time. If this heat cannot be dissipated promptly, it can seriously impact the safety and service life of the circuit board. Summary of the Invention

[0003] In view of this, the present application provides a method for manufacturing a circuit board with better heat dissipation effect.

[0004] In addition, it is also necessary to provide a circuit board manufactured by the above manufacturing method.

[0005] The present application provides a method for manufacturing a circuit board, comprising the following steps:

[0006] Providing a heat dissipation substrate, comprising a phase change structure and a heat conductive layer, wherein the heat conductive layer covers the phase change structure, and the heat dissipation substrate is provided with a first through hole;

[0007] forming an insulating layer on the surface of the heat dissipation substrate, wherein the insulating layer is provided with a groove;

[0008] Arranging an electronic component in the groove, and making the electronic component thermally conductive with the heat conductive layer;

[0009] forming a single-sided copper-clad substrate on the insulating layer, wherein the single-sided copper-clad substrate comprises a base layer and a copper foil layer, wherein the base layer is provided between the copper foil layer and the electronic component;

[0010] A second through hole is opened in the single-sided copper clad substrate and the insulating layer, wherein the bottom of the second through hole corresponds to the heat conducting layer;

[0011] Filling the second through hole with a heat-conducting material to form a heat-conducting portion;

[0012] electroplating metal on the copper foil layer to form a copper-plated layer; and

[0013] The copper plating layer and the copper foil layer are etched to form a conductive circuit layer, thereby obtaining the circuit board.

[0014] The present application also provides a circuit board, comprising:

[0015] A heat dissipation substrate, comprising a phase change structure and a heat conductive layer, wherein the heat conductive layer covers the phase change structure, and the heat dissipation substrate is provided with a first through hole;

[0016] an insulating layer on a surface of the heat dissipation substrate, the insulating layer being provided with a recess;

[0017] an electronic component in the recess, and the electronic component being in thermal conduction with the heat conducting layer;

[0018] a base layer on the insulating layer, and the electronic component being between the base layer and the insulating layer; and

[0019] a conductive circuit layer formed on the base layer;

[0020] wherein the conductive circuit layer, the base layer and the insulating layer are provided with a second through hole, a bottom of the second through hole corresponding to the heat conducting layer, and a heat conducting material being filled in the second through hole to form a heat conducting part.

[0021] The heat dissipation substrate in the present application includes the phase change structure, and the heat generated by the electronic component in operation can be transmitted to the phase change structure through the heat conducting layer, and the phase change structure absorbs the heat generated by the electronic component, thereby reducing the temperature of the electronic component and improving the heat dissipation performance of the electronic component. Meanwhile, the heat conducting material is filled in the second through hole to form the heat conducting part, and the heat generated by the conductive circuit layer can be transmitted to the phase change structure through the heat conducting part, and the phase change structure absorbs the heat generated by the conductive circuit layer, thereby reducing the temperature of the conductive circuit layer and improving the heat dissipation performance of the conductive circuit layer. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 is a structural schematic diagram of a first metal layer provided by some embodiments of the present application.

[0023] Figure 2 is a structural schematic diagram after a first accommodating groove and a first connecting hole are formed on a surface of the first metal layer shown in Figure 1

[0024] Figure 3 is a structural schematic diagram after a first phase change layer is formed in the first accommodating groove, and a solder is filled in the first connecting hole shown in Figure 2

[0025] Figure 4 is a structural schematic diagram of a second metal layer provided by some embodiments of the present application.

[0026] Figure 5 is a structural schematic diagram after a second opening and a second connecting hole are formed in the dielectric layer and the second metal layer shown in Figure 4

[0027] Figure 6 Figure 5 ​​​​The schematic diagram of the structure after the connecting column is formed in the second connecting hole is shown.

[0028] Figure 7 It will Figure 6 Schematic diagram of the structure after the dielectric layer is removed.

[0029] Figure 8 is Figure 7 The diagram shows a structure after a second receiving groove is opened in the second metal layer.

[0030] Figure 9 is Figure 8 The diagram shows a structural diagram after the second phase change layer is formed in the second containing groove.

[0031] Figure 10 It will Figure 3 The first substrate and Figure 9 The schematic diagram of the structure of the second substrate after lamination is shown.

[0032] Figure 11 is Figure 10 The figure shows a schematic structural diagram of a heat dissipation substrate after insulating layers are formed on two opposite surfaces thereof.

[0033] Figure 12 is Figure 11 Schematic diagram of the structure after grooves are opened in the insulating layer shown.

[0034] Figure 13 is Figure 12 Schematic diagram of the structure after the bonding sheet is formed in the groove shown.

[0035] Figure 14 is Figure 13 Schematic diagram of the structure after a single-sided copper-clad substrate is formed on the insulating layer shown.

[0036] Figure 15 is Figure 14 The diagram shows a schematic diagram of the structure of a single-sided copper clad substrate and an insulating layer after a second through hole is opened.

[0037] Figure 16 is Figure 15 The schematic diagram of the structure after the heat conduction portion is formed in the second through hole is shown.

[0038] Figure 17 is Figure 16 The schematic diagram of the structure after a groove is opened in the single-sided copper clad substrate and a third through hole is opened in the single-sided copper clad substrate and the insulating layer is shown.

[0039] Figure 18 is Figure 17 Schematic diagram of the structure after a copper plating layer is formed on the copper foil layer shown.

[0040] Figure 19 It will Figure 18 The schematic diagram of the structure of the circuit board obtained after etching the copper plating layer and the copper foil layer is shown.

[0041] Description of main component symbols

[0042] Circuit board 100

[0043] First metal layer 10

[0044] First opening 11

[0045] First accommodating groove 12

[0046] First connecting hole 13

[0047] First phase change layer 20

[0048] Solder 21

[0049] First substrate 22

[0050] Second phase change layer 23

[0051] Phase change structure 24

[0052] Second metal layer 30

[0053] Dielectric layer 31

[0054] Second opening 32

[0055] Second connecting hole 33

[0056] Connecting column 40

[0057] Accommodation groove 41

[0058] Second substrate 42

[0059] First through hole 43

[0060] Thermal conductive layer 44

[0061] Heat dissipation substrate 50

[0062] Insulation layer 60

[0063] Groove 61

[0064] Adhesive sheet 70

[0065] Electronic components 71

[0066] Single-sided copper clad substrate 80

[0067] Grassroots 81

[0068] Copper foil layer 82

[0069] Second through hole 83

[0070] Heat transfer portion 84

[0071] Slotted 85

[0072] The third through hole 86

[0073] Copper plating layer 90

[0074] First conductive portion 91

[0075] Second conductive portion 92

[0076] Conductive circuit layer 93

[0077] The following specific implementation methods will further illustrate this application in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0078] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments.

[0079] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application pertains. The terms used herein in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application.

[0080] In order to further illustrate the technical means and effects adopted by this application to achieve the intended purpose, the following detailed description of this application is made in conjunction with the accompanying drawings and preferred implementation methods.

[0081] Some embodiments of the present application provide a method for manufacturing a circuit board, comprising the following steps:

[0082] Step S11, please refer to Figure 1 , providing a first metal layer 10.

[0083] The first metal layer 10 is provided with a first opening 11, and the first opening 11 passes through the first metal layer 10. In some embodiments, the first opening 11 can be formed by laser cutting.

[0084] The first metal layer 10 has high mechanical strength and high thermal conductivity. In some embodiments, the first metal layer 10 can be made of copper alloy, aluminum alloy or copper-aluminum alloy.

[0085] Step S12, see Figure 2 A first receiving groove 12 and a first connecting hole 13 are formed on the surface of the first metal layer 10 .

[0086] The first accommodating groove 12 and the first connecting hole 13 are located on the same surface of the first metal layer 10, and neither of them penetrates the first metal layer 10.

[0087] In some embodiments, each first accommodating groove 12 is provided with a first connecting hole 13 on each side.

[0088] In some embodiments, the first accommodating groove 12 and the first connecting hole 13 can be formed by etching.

[0089] Step S13, please refer to Figure 3 filling the first accommodating groove 12 with a phase change material to form a first phase change layer 20, and filling the first connecting hole 13 with solder 21, thereby obtaining a first substrate 22.

[0090] In some embodiments, the material of the first phase change layer 20 can be paraffin (C n H 2n+2 ), inorganic salt hydrate or fatty acid. In some embodiments, the inorganic salt hydrate includes at least one of disodium phosphate dodecahydrate, calcium nitrate tetrahydrate and sodium acetate trihydrate, and the fatty acid includes at least one of lauric acid and myristic acid.

[0091] In some embodiments, the first phase change layer 20 fills the first accommodating groove 12, and the solder 21 only fills the bottom of the first connecting hole 13.

[0092] Step S14, please refer to Figure 4 , providing a second metal layer 30 and a dielectric layer 31.

[0093] The dielectric layer 31 is arranged on the surface of the second metal layer 30. In some embodiments, the dielectric layer 31 can be a peelable film.

[0094] The material of the second metal layer 30 is the same as that of the first metal layer 10, and specific reference can be made to the material of the first metal layer 10, which will not be described here in detail.

[0095] Step S15, please refer to Figure 5 , providing a second opening 32 and a second connecting hole 33 in the dielectric layer 31 and the second metal layer 30.

[0096] The second opening 32 penetrates the dielectric layer 31 and the second metal layer 30 in sequence, and the second connecting hole 33 penetrates the dielectric layer 31 but does not penetrate the second metal layer 30.

[0097] In some embodiments, the second opening 32 and the second connection hole 33 may be formed by laser cutting.

[0098] In some embodiments, a second connecting hole 33 is defined on both sides of each second opening 32 .

[0099] Step S16, see Figure 6 , metal is electroplated in the second connection hole 33 to form a connection column 40 .

[0100] In some embodiments, a surface of the connecting pillar 40 away from the second metal layer 30 is substantially flush with a surface of the dielectric layer 31 away from the second metal layer 30 .

[0101] Step S17, please refer to Figure 7 , remove the dielectric layer 31.

[0102] After the dielectric layer 31 is removed, the connecting pillar 40 is away from the surface of the second metal layer 30 and protrudes from the surface of the second metal layer 30 .

[0103] Step S18, please refer to Figure 8 , a second receiving groove 41 is opened in the second metal layer 30 .

[0104] The second receiving groove 41 and the connecting pillar 40 are located on the same surface of the second metal layer 30, and the second receiving groove 41 does not penetrate the second metal layer 30. In some embodiments, a connecting pillar 40 is disposed on both sides of each second receiving groove 41.

[0105] In some embodiments, the second receiving groove 41 may be formed by etching.

[0106] Step S19, please refer to Figure 9 , the phase change material is filled in the second containing groove 41 to form a second phase change layer 23 , thereby obtaining a second substrate 42 .

[0107] In some embodiments, the second phase change layer 23 may be made of the same material as the first phase change layer 20 . Detailed description is omitted here, and reference may be made to the material of the first phase change layer 20 for details.

[0108] Step S10, see Figure 10, press the first substrate 22 and the second substrate 42 together, so that the connecting column 40 is located in the first connecting hole 13 and connected to the solder 21, and the first opening 11 and the second opening 32 are opposite to each other to form a first through hole 43, the first metal layer 10 and the second metal layer 30 are opposite to each other to form a thermal conductive layer 44, and the first phase change layer 20 and the second phase change layer 23 are combined to form a phase change structure 24, thereby obtaining a heat dissipation substrate 50.

[0109] The heat-conducting layer 44 covers the phase change structure 24 , and the first through hole 43 passes through the heat dissipation substrate 50 .

[0110] In this embodiment, the solder 21 and the connecting pillars 40 are used to fix the first substrate 22 and the second substrate 42 .

[0111] Step S11, please refer to Figure 11 Insulating layers 60 are formed on two opposite surfaces of the heat dissipation substrate 50 .

[0112] The insulating layer 60 is also filled in the first through hole 43 .

[0113] The insulating layer 60 may be made of a material selected from epoxy resin, polypropylene (PP), BT resin, polyphenylene oxide (PPO), polyimide (PI), polyethylene terephthalate (PET), and polyethylene naphthalate (PEN). In this embodiment, the insulating layer 60 is made of polypropylene.

[0114] Step S12, please refer to Figure 12 , a groove 61 is opened in each of the insulating layers 60 .

[0115] The bottom of the groove 61 corresponds to the heat-conducting layer 44 , that is, the heat-conducting layer 44 is exposed in the groove 61 .

[0116] Step S13, please refer to Figure 13 , a bonding sheet 70 is provided in each of the grooves 61 .

[0117] Specifically, the bonding sheet 70 is disposed on the heat-conducting layer 44 and is thermally connected to the heat-conducting layer 44 .

[0118] The adhesive sheet 70 has good heat conduction performance. In some embodiments, the adhesive sheet 70 can be made of high-silicon conductive glue or acrylic resin.

[0119] In step S14, an electronic component 71 is disposed on each adhesive sheet 70, and the electronic component 71 is located in the groove 61.

[0120] In this embodiment, the electronic component 71 can partially protrude from the insulating layer 60.

[0121] The heat generated by the two electronic components 71 during operation can be transmitted to the phase change structure 24 through the adhesive sheet 70 and the heat conduction layer 44, and the heat generated by the electronic components 71 can be absorbed by the phase change structure 24, thereby reducing the temperature of the electronic components 71 and improving the heat dissipation performance of the electronic components 71.

[0122] In step S15, referring to Figure 14 A single-sided copper clad board 80 is formed on each insulating layer 60.

[0123] In some embodiments, each single-sided copper clad board 80 includes a base layer 81 and a copper foil layer 82.

[0124] The base layer 81 is disposed between the copper foil layer 82 and the electronic component 71. The portion of the electronic component 71 protruding from the insulating layer 60 is embedded in the base layer 81.

[0125] The base layer 81 can be made of one of epoxy resin, polypropylene (PP), BT resin, polyphenylene oxide (PPO), polyimide (PI), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and other resins. In this embodiment, the base layer 81 is made of polyimide.

[0126] In step S16, referring to Figure 15 A second through hole 83 is formed in each single-sided copper clad board 80 and the insulating layer 60.

[0127] The bottom of each second through hole 83 corresponds to the heat conduction layer 44.

[0128] In step S17, referring to Figure 16 A heat conduction portion 84 is filled in each second through hole 83.

[0129] The heat conducting portion 84 is thermally connected to the heat conducting layer 44 .

[0130] In some embodiments, the thermally conductive material may be a graphite sheet, a thermally conductive gel, or silicone.

[0131] In some other embodiments, each of the second through holes 83 may be plated with tin to form the heat conducting portion 84 .

[0132] Step S18, please refer to Figure 17 A slot 85 is formed in each of the single-sided copper clad substrates 80 , and a third through hole 86 is formed in each of the single-sided copper clad substrates 80 and the insulating layer 60 .

[0133] The bottom of the slot 85 corresponds to the electronic component 71. In some embodiments, the inner diameter of the slot 85 decreases from the upper end of the slot 85 toward the bottom.

[0134] The third through hole 86 corresponds to the first through hole 43, and the inner diameter of the third through hole 86 is smaller than the inner diameter of the first through hole 43. The third through hole 86 sequentially passes through the copper foil layer 82, the base layer 81, the insulating layer 60, the base layer 81, and the copper foil layer 82.

[0135] Step S19, please refer to Figure 18 Metal is electroplated on each of the copper foil layers 82 to form a copper-plated layer 90 , and the metal is also filled in the grooves 85 and the third through holes 86 to form a first conductive portion 91 and a second conductive portion 92 , respectively.

[0136] Step S20, see Figure 19 , the two copper-plated layers 90 and the two copper foil layers 82 are etched respectively to form two conductive circuit layers 93 , thereby obtaining the circuit board 100 .

[0137] The first conductive portion 91 is used to electrically connect the conductive circuit layer 93 and the adjacent electronic component 71 , and the second conductive portion 92 is used to electrically connect the two conductive circuit layers 93 .

[0138] The heat generated by the two conductive circuit layers 93 can be transferred to the phase change structure 24 through the heat conducting portion 84 , and the phase change structure 24 absorbs the heat generated by the conductive circuit layer 93 , thereby reducing the temperature of the conductive circuit layer 93 and improving the heat dissipation performance of the conductive circuit layer 93 .

[0139] See also Figure 19Some embodiments of the present application further provide a circuit board 100 , which includes a heat dissipation substrate 50 , an insulating layer 60 , an adhesive sheet 70 , electronic components 71 , a base layer 81 and a conductive circuit layer 93 .

[0140] In some embodiments, the heat dissipation substrate 50 includes a first substrate 22 and a second substrate 42 .

[0141] The first substrate 22 includes a first metal layer 10. The first metal layer 10 has high mechanical strength and high thermal conductivity. In some embodiments, the first metal layer 10 can be made of copper alloy, aluminum alloy, or copper-aluminum alloy.

[0142] The first metal layer 10 defines a first opening 11 , and the first opening 11 penetrates the first metal layer 10 .

[0143] A first receiving groove 12 and a first connection hole 13 are formed on the surface of the first metal layer 10. The first receiving groove 12 and the first connection hole 13 are located on the same surface of the first metal layer 10, and neither the first receiving groove 12 nor the first connection hole 13 penetrates the first metal layer 10. In some embodiments, a first connection hole 13 is provided on both sides of each first receiving groove 12.

[0144] The first receiving groove 12 is filled with a phase change material to form a first phase change layer 20, and the first connecting hole 13 is filled with solder 21. In some embodiments, the first phase change layer 20 completely fills the first receiving groove 12, and the solder 21 only fills the bottom of the first connecting hole 13.

[0145] In some embodiments, the material of the first phase change layer 20 may be paraffin (C n H 2n+2 ), an inorganic salt hydrate or a fatty acid. In some embodiments, the inorganic salt hydrate comprises at least one of disodium phosphate dodecahydrate, calcium nitrate tetrahydrate, and sodium acetate trihydrate, and the fatty acid comprises at least one of lauric acid and myristic acid.

[0146] The second substrate 42 includes a second metal layer 30. The material of the second metal layer 30 is the same as that of the first metal layer 10. For details, please refer to the material of the first metal layer 10, which will not be described in detail here.

[0147] A second opening 32 and a second connection hole 33 are defined in the second metal layer 30. The second opening 32 passes through the second metal layer 30, while the second connection hole 33 does not pass through the second metal layer 30. In some embodiments, a second connection hole 33 is defined on both sides of each second opening 32.

[0148] Metal is electroplated in the second connection hole 33 to form a connection column 40 , wherein the connection column 40 is away from the surface of the second metal layer 30 and protrudes from the surface of the second metal layer 30 .

[0149] A second receiving groove 41 is defined in the second metal layer 30. The second receiving groove 41 and the connecting pillar 40 are located on the same surface of the second metal layer 30, and the second receiving groove 41 does not penetrate the second metal layer 30. In some embodiments, a connecting pillar 40 is provided on each side of each second receiving groove 41.

[0150] The second receiving groove 41 is filled with a phase change material to form a second phase change layer 23. In some embodiments, the second phase change layer 23 can be made of the same material as the first phase change layer 20. Detailed description is omitted here, and the material of the first phase change layer 20 may be referred to.

[0151] In which, the connecting column 40 is located in the first connecting hole 13 and is connected to the solder 21, the first opening 11 is opposite to the second opening 32 to form a first through hole 43, the first metal layer 10 is opposite to the second metal layer 30 to form a thermal conductive layer 44, and the first phase change layer 20 is combined with the second phase change layer 23 to form a phase change structure 24.

[0152] The heat-conducting layer 44 covers the phase change structure 24 , and the first through hole 43 passes through the heat dissipation substrate 50 .

[0153] In this embodiment, the solder 21 and the connecting pillars 40 are used to fix the first substrate 22 and the second substrate 42 .

[0154] The two insulating layers 60 are respectively located on two opposite surfaces of the heat dissipation substrate 50 , and the insulating layers 60 are also filled in the first through holes 43 .

[0155] The insulating layer 60 may be made of a material selected from epoxy resin, polypropylene (PP), BT resin, polyphenylene oxide (PPO), polyimide (PI), polyethylene terephthalate (PET), and polyethylene naphthalate (PEN). In this embodiment, the insulating layer 60 is made of polypropylene.

[0156] A groove 61 is formed in each of the insulating layers 60 , wherein the bottom of the groove 61 corresponds to the heat conducting layer 44 , that is, the heat conducting layer 44 is exposed in the groove 61 .

[0157] The two bonding sheets 70 are respectively located in the two grooves 61. Specifically, the bonding sheets 70 are provided on the heat conducting layer 44 and are thermally connected to the heat conducting layer 44.

[0158] The bonding sheet 70 has good thermal conductivity. In some embodiments, the bonding sheet 70 can be made of highly conductive silicone or acrylic resin.

[0159] The two electronic components 71 are respectively disposed on each bonding sheet 70 , disposed in the groove 61 , and are thermally connected to the heat conducting layer 44 .

[0160] In this embodiment, the electronic component 71 may partially protrude from the insulating layer 60 .

[0161] The heat generated by the two electronic components 71 during operation can be transferred to the phase change structure 24 through the bonding sheet 70 and the heat conductive layer 44 , and the phase change structure 24 absorbs the heat generated by the electronic components 71 , thereby reducing the temperature of the electronic components 71 and improving the heat dissipation performance of the electronic components 71 .

[0162] The two base layers 81 are respectively located on the two insulating layers 60 , and the electronic component 71 is located between the base layer 81 and the insulating layer 60 . Parts of the electronic component 71 protruding from the insulating layer 60 are embedded in the base layer 81 .

[0163] The base layer 81 may be made of a material selected from epoxy resin, polypropylene (PP), BT resin, polyphenylene oxide (PPO), polyimide (PI), polyethylene terephthalate (PET), and polyethylene naphthalate (PEN). In this embodiment, the base layer 81 is made of polyimide.

[0164] Two conductive circuit layers 93 are formed on the base layer 81. Second through holes 83 are defined in each conductive circuit layer 93, the base layer 81, and the insulating layer 60. The bottom of each second through hole 83 corresponds to the thermally conductive layer 44. Each second through hole 83 is filled with a thermally conductive material to form a thermally conductive portion 84. The thermally conductive portion 84 is thermally conductively connected to the thermally conductive layer 44.

[0165] In some embodiments, the thermally conductive material may be a graphite sheet, a thermally conductive gel, or silicone.

[0166] A slot 85 is defined in each of the conductive circuit layers 93 and the base layer 81, and a third through hole 86 is defined in each of the conductive circuit layers 93, the base layer 81, and the insulating layer 60. The bottom of each slot 85 corresponds to the electronic component 71. In some embodiments, the inner diameter of each slot 85 decreases from the top of each slot 85 toward the bottom. The third through hole 86 corresponds to the first through hole 43, and the inner diameter of each third through hole 86 is smaller than the inner diameter of the first through hole 43.

[0167] The slot 85 and the third through hole 86 are filled with metal to form a first conductive portion 91 and a second conductive portion 92. The first conductive portion 91 is used to electrically connect the conductive circuit layer 93 to the adjacent electronic component 71, and the second conductive portion 92 is used to electrically connect the two conductive circuit layers 93.

[0168] The heat generated by the two conductive circuit layers 93 can be transferred to the phase change structure 24 through the heat conducting portion 84 , and the phase change structure 24 absorbs the heat generated by the conductive circuit layer 93 , thereby reducing the temperature of the conductive circuit layer 93 and improving the heat dissipation performance of the conductive circuit layer 93 .

[0169] The heat dissipation substrate 50 in the present application includes the phase change structure 24. The heat generated by the two electronic components 71 during operation can be transferred to the phase change structure 24 through the adhesive sheet 70 and the thermally conductive layer 44. The phase change structure 24 absorbs the heat generated by the electronic components 71, thereby reducing the temperature of the electronic components 71 and improving the heat dissipation performance of the electronic components 71. At the same time, the present application fills the second through-hole 83 with a thermally conductive material to form the thermally conductive portion 84. The heat generated by the two conductive circuit layers 93 can be transferred to the phase change structure 24 through the thermally conductive portion 84. The phase change structure 24 absorbs the heat generated by the conductive circuit layer 93, thereby reducing the temperature of the conductive circuit layer 93 and improving the heat dissipation performance of the conductive circuit layer 93.

[0170] The present application also disposes the heat dissipation substrate 50 inside the circuit board 100, which simplifies the manufacturing process, saves raw materials, and thus reduces production costs. In addition, the present application also embeds the electronic component 71 inside the circuit board 100, thereby reducing the thickness of the circuit board 100.

[0171] The above description is only an optimized specific implementation of the present application, but it is not limited to this implementation in actual application. For ordinary technicians in this field, other variations and changes made according to the technical concept of the present application should fall within the scope of protection of the present application.

Claims

1. A method for manufacturing a circuit board, characterized in that: The following steps are involved: A heat dissipation substrate is provided, comprising a phase change structure and a heat conductive layer, wherein the heat conductive layer covers the phase change structure, and the heat dissipation substrate is provided with a first through hole. A method for manufacturing the heat dissipation substrate comprises: A first substrate is provided, wherein a first accommodating groove and a first connecting hole are formed on a surface of the first substrate, a first phase change layer is provided in the first accommodating groove, solder is provided in the first connecting hole, and the first substrate further has a first opening that penetrates the first substrate; Providing a second substrate, wherein a second accommodating groove and a second connecting hole are formed on a surface of the second substrate, a second phase change layer is disposed in the second accommodating groove, a connecting post is disposed in the second connecting hole, the connecting post protruding from the surface of the second substrate away from the surface of the second substrate, and the second substrate further has a second opening, the second opening penetrating the second substrate; and Pressing the first substrate and the second substrate together, positioning the connecting column in the first connecting hole and connecting to the solder, positioning the first opening opposite to the second opening to form the first through hole, and combining the first phase change layer with the second phase change layer to form the phase change structure; forming an insulating layer on the surface of the heat dissipation substrate, wherein the insulating layer is provided with a groove; Arranging an electronic component in the groove, and making the electronic component thermally conductive with the heat conductive layer; forming a single-sided copper-clad substrate on the insulating layer, wherein the single-sided copper-clad substrate comprises a base layer and a copper foil layer, wherein the base layer is provided between the copper foil layer and the electronic component; A second through hole is opened in the single-sided copper clad substrate and the insulating layer, wherein the bottom of the second through hole corresponds to the heat conducting layer; Filling the second through hole with a heat conductive material to form a heat conductive portion; electroplating metal on the copper foil layer to form a copper-plated layer; and The copper plating layer and the copper foil layer are etched to form a conductive circuit layer, thereby obtaining the circuit board.

2. The method for manufacturing a circuit board according to claim 1, wherein: After forming the heat conducting portion, the manufacturing method further includes: A groove is formed in the single-sided copper clad substrate, and a third through hole is formed in the single-sided copper clad substrate and the insulating layer, wherein the bottom of the groove corresponds to the electronic component, and the third through hole corresponds to the first through hole; When metal is electroplated on the copper foil layer to form the copper-plated layer, the metal is also filled in the slot and the third through hole to form a first conductive portion and a second conductive portion respectively.

3. The method for manufacturing a circuit board according to claim 1, wherein: After forming the insulating layer on the surface of the heat dissipation substrate, the manufacturing method further includes: providing a bonding sheet in the groove; Wherein, the electronic components are arranged on the bonding sheet.

4. The method for manufacturing a circuit board according to claim 1, wherein: The manufacturing method of the first substrate includes: Providing a first metal layer, wherein the first metal layer is provided with the first opening; forming the first receiving groove and the first connecting hole on the surface of the first metal layer; and The first receiving groove is filled with a phase change material to form the first phase change layer, and the first connection hole is filled with the solder.

5. The method for manufacturing a circuit board according to claim 1, wherein: The manufacturing method of the second substrate includes: Providing a second metal layer, wherein a dielectric layer is provided on a surface of the second metal layer; opening the second opening and the second connection hole in the dielectric layer and the second metal layer; Electroplating metal in the second connection hole to form the connection column, wherein a surface of the connection column away from the second metal layer is flush with a surface of the dielectric layer away from the second metal layer; removing the dielectric layer; opening the second receiving groove in the second metal layer; and The second containing groove is filled with a phase change material to form the second phase change layer.

6. A circuit board, characterized in that: include: A heat dissipation substrate, comprising a phase change structure and a heat conductive layer, wherein the heat conductive layer covers the phase change structure, and the heat dissipation substrate is provided with a first through hole; The heat dissipation substrate comprises: A first substrate, wherein a first accommodating groove and a first connecting hole are formed on a surface of the first substrate, a first phase change layer is provided in the first accommodating groove, solder is provided in the first connecting hole, and the first substrate further has a first opening, the first opening penetrating the first substrate; and a second substrate, wherein a second accommodating groove and a second connecting hole are formed on a surface of the second substrate, a second phase change layer is formed in the second accommodating groove, a connecting post is formed in the second connecting hole, the connecting post protrudes from the surface of the second substrate away from the surface of the second substrate, and the second substrate further comprises a second opening, the second opening penetrating the second substrate; wherein the connecting column is located in the first connecting hole and connected to the solder, the first opening is opposite to the second opening to form the first through hole, and the first phase change layer is combined with the second phase change layer to form the phase change structure; an insulating layer, located on the surface of the heat dissipation substrate, wherein the insulating layer is provided with a groove; an electronic component disposed in the groove, and the electronic component is thermally connected to the heat-conducting layer; a base layer located on the insulating layer, with the electronic component located between the base layer and the insulating layer; and A conductive circuit layer is formed on the base layer; A second through hole is opened in the conductive circuit layer, the base layer and the insulating layer, the bottom of the second through hole corresponds to the heat conducting layer, and the second through hole is filled with a heat conducting material to form a heat conducting portion.

7. The circuit board according to claim 6, wherein: A groove is opened in the conductive circuit layer and the base layer, and a third through hole is opened in the conductive circuit layer, the base layer and the insulating layer. The bottom of the groove corresponds to the electronic component, and the third through hole corresponds to the first through hole. The groove and the third through hole are filled with metal to form a first conductive part and a second conductive part, respectively.

8. The circuit board according to claim 6, wherein: The circuit board further includes a bonding sheet, the bonding sheet is located in the groove, and the electronic component is located on the bonding sheet.

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