KR20100015124A - Printed circuit board and the manufacturing method thereof - Google Patents

Abstract

PURPOSE: A printed circuit board and a manufacturing method thereof are provided to improve space usability and thermal conductivity by emitting heat produced in a device through a heat pipe to the outside. CONSTITUTION: A first prepreg layer(121) is welded between a first substrate and a second substrate. A penetrated hole is formed through the first prepreg. A heat pipe is built in the penetrated hole. A second prepreg layer(122) and a third preprege layer(123) are laminated on the bottom of the second substrate and the top of the first substrate. An external layer circuit(135a,135b) is equipped on the bottom of the third preprege layer and the top of the second prepreg layer.

Description

Printed circuit board and the manufacturing method

The present invention relates to a printed circuit board and a method of manufacturing the same, and more particularly, to a printed circuit board and a manufacturing method for embedding a heat pipe in the printed circuit board.

In devices using sophisticated circuit boards such as laptops, desktop computers, LCD TVs, and PDP TVs, heat dissipation and cooling have been pointed out as an important issue directly related to the reliability of the devices.

In particular, due to the high integration of semiconductor devices and miniaturization of devices used in circuit boards, the performance of devices is further improved, but heat dissipation per unit area of semiconductor chips tends to increase. Problems such as these are extremely detrimental to the reliability of the product.

Accordingly, when heat is generated in the semiconductor element by attaching a heat sink to the semiconductor element, the heat is conducted to a heat sink of a metal or ceramic material having a relatively lower temperature than the semiconductor element, and the conducted heat Heat was released to the outside of the heat sink to prevent overheating of the semiconductor element.

However, in order to reduce the time for transferring heat to the heat sink having the above structure and to increase the amount of heat released within the same time, it is effective to increase the width of the heat sink to form the heat sink. Since it is impossible to mount other electronic components on the substrate, when the width of the heat sink is increased for more efficient heat dissipation than the existing heat sink, a problem arises in that the size of the circuit board must be increased.

In addition, in order to increase the width of the circuit board, the size of the electronic product to embed the circuit board is also naturally increased, and there is a problem of repositioning the existing electronic components.

therefore. It is a matter of course that the reliability of the product is lowered due to the problems described above, and thus the external competitiveness is lowered.

Accordingly, the present invention is to solve the above disadvantages and problems, the printed circuit board and the thermal conductivity for improving the thermal conductivity and space utilization for dissipating heat generated in the device to the outside by embedding the heat pipe in the printed circuit board and its The purpose is to provide a manufacturing method.

A printed circuit board according to the first embodiment of the present invention for achieving the above object is a circuit formed on both sides, the first substrate and the second substrate and the first substrate and the second substrate is interposed between the bonding A first prepreg layer; A through hole formed through the first prefrag layer bonded between the first substrate and the second substrate; A heat pipe embedded in the through hole; A second prepreg layer and a third prepreg layer stacked on the first substrate and the second substrate, respectively; And an outer layer circuit provided on an upper surface of the second prepreg layer and a lower surface of the third prepreg layer.

In addition, a coolant may be injected into the heat pipe, and a fine flow path through which the coolant flows may be formed.

In addition, the wall of the heat pipe may be made of copper or aluminum.

In addition, the through hole may be formed by a drill or an NC router.

In addition, an element coated on a lower surface of the conductive material may be attached to the outer circuit provided on the upper surface of the second prepreg layer.

In addition, the conductive material may be formed of a conductive paste or a solder paste.

In addition, the second prepreg layer may have a via hole for electrically connecting the element attached to the outer layer circuit and the heat pipe.

In addition, the via may be formed by a laser.

Method of manufacturing a printed circuit board according to a first embodiment of the present invention for achieving the above object comprises the steps of preparing a first substrate and a second substrate with a circuit formed on both sides; Bonding and laminating a first prepreg layer between the first substrate and the second substrate; Forming a through hole penetrating the stacked first substrate, the second substrate, and the first prepreg layer; Embedding a heat pipe in the through hole; Bonding and stacking a second prepreg layer on the first substrate and a third prepreg layer on the bottom surface of the second substrate; And forming an outer layer circuit on an upper surface of the second prepreg layer and a lower surface of the third prepreg layer.

In addition, after the bonding and laminating a second prepreg layer on the first substrate and a third prepreg layer on the lower surface of the second substrate, the second prepreg layer and the element attached to the outer layer circuit and the heat A via hole may be further included to electrically connect the pipe.

In addition, after forming the outer layer circuit on the upper surface of the second prepreg layer and the lower surface of the third prefrag layer, the surface of the outer layer circuit is coated with PSR, and the surface treatment operation and appearance processing including exposure and development are performed. The method may further include attaching a device having a conductive material to the outer circuit formed on the second prepreg layer.

A method of manufacturing a printed circuit board according to a first embodiment of the present invention for achieving the above object comprises the steps of preparing a first substrate and a second substrate having a circuit formed on both sides, the through-holes therein; Bonding and stacking the first and second substrates between the first substrate and the second substrate, the first prepreg layer having a through hole corresponding to the through hole; Embedding a heat pipe in the through hole; Bonding and stacking a second prepreg layer on an upper surface of the first substrate and a third prepreg layer on a lower surface of the second substrate; And forming an outer layer circuit on an upper surface of the second prepreg layer and a lower surface of the third prepreg layer.

The printed circuit board according to the second embodiment of the present invention for achieving the above object is a circuit formed on both sides, the first substrate and the second substrate and the first substrate and the second substrate is interposed between the bonding A first prepreg layer; A through hole formed through the first prefrag layer bonded between the first substrate and the second substrate; A heat pipe embedded in the through hole and having a metal material bonded to both outer surfaces thereof; A second prefrag layer and a third prefrag layer stacked on the first substrate and the second substrate, respectively, on a bottom surface thereof; an outer circuit provided on an upper surface of the second prefrag layer and a bottom surface of the third prefrag layer; It may be made, including.

In addition, a coolant may be injected into the heat pipe, and a fine flow path through which the coolant flows may be formed.

In addition, one side surface of the metal material bonded to the heat pipe may protrude outwardly from end portions of the first substrate and the second substrate.

In addition, the printed circuit board may pass through a metal material bonded to the heat pipe, including the first substrate and the second substrate.

Method of manufacturing a printed circuit board according to a second embodiment of the present invention for achieving the above object comprises the steps of preparing a first substrate and a second substrate with a circuit formed on both sides; Bonding and laminating a first prepreg layer between the first substrate and the second substrate; Forming a through hole in an end side of the stacked first substrate, the second substrate, and the first prepreg layer; Embedding a heat pipe in which metal materials are bonded to both outer surfaces of the through hole; bonding and stacking a second prepreg layer on an upper surface of the first substrate and a third prepreg layer on a lower surface of the second substrate; And forming an outer layer circuit on an upper surface of the second prepreg layer and a lower surface of the third prepreg layer.

The printed circuit board may include the first substrate and the second substrate after bonding and laminating a second prepreg layer on the first substrate and a third prepreg layer on the bottom surface of the second substrate. The method may further include forming a through hole therethrough.

In addition, after forming the outer layer circuits on the upper surface of the second prepreg layer and the lower surface of the third prefrag layer, the surface of the outer layer circuit is coated with PSR, and surface treatment operations including surface exposure and development and appearance processing are performed. The method may further include attaching a device having a conductive material to the outer circuit formed on the second prepreg layer.

As described above, the printed circuit board and the method of manufacturing the same according to the present invention improve the thermal conductivity for releasing heat generated from the device by embedding a heat pipe in the printed circuit board, thereby shortening the heat conduction time.

In addition, the space utilization is improved by removing the heat sink attached to the device, which reduces the overall cost of the printed circuit board.

In addition, the semi-permanent life of the heat pipe minimizes the defective rate of the printed circuit board to improve the reliability and efficiency of the product.

Matters relating to the operational effects including the technical configuration of the printed circuit board and the manufacturing method according to the present invention will be clearly understood by the following detailed description with reference to the drawings showing preferred embodiments of the present invention.

A printed circuit board and a method of manufacturing the same according to the first embodiment of the present invention will be described in detail with reference to FIGS. 1 to 9.

1 is a cross-sectional view of a printed circuit board 100 according to a first embodiment of the present invention.

Referring to FIG. 1, the printed circuit board 100 according to the first embodiment of the present invention may be divided into a first substrate 111 and a second substrate 112, a first prepreg layer 121, and a first substrate. 2 prepreg layer 122, third prepreg layer 123, heat pipe 130. It includes the outer circuit (135a, 135b).

Circuit patterns subjected to exposure, development, and etching after pressing copper foil layers on both surfaces of the first substrate 111 and the second substrate 112 by pressing many types of components on both sides of the substrate, such as phenol resin and epoxy resin. 111a and 112a are formed,

In addition, a first prepreg layer 121 is stacked between the first substrate 111 and the second substrate 112.

In this case, the first prepreg layer 121 serves to increase the insulation between the first substrate 111 and the second substrate 112.

The through hole 125 penetrating the first substrate 111, the second substrate 112, and the first prepreg layer 121 stacked in this manner is formed, and the through hole 125 is drilled or It is formed by the NC router.

And the heat pipe 130 is built in the through-hole 125.

A fluid that acts as a refrigerant is injected into the heat pipe 130, and the fluid absorbs heat from the process of repeating condensation and evaporation, and transfers heat by the flow of the fluid through a microchannel. do. At this time, the wall of the heat pipe 130 is made of a copper or aluminum material.

As such, when the heat pipe 130 is embedded in the printed circuit board 100, the thermal conductivity for dissipating heat generated from the device 140 to the outside is improved, thereby shortening the thermal conduction time.

Next, a second prepreg layer 122 is stacked on the first substrate 111 having the heat pipe 130 embedded therein, and a third prepreg layer 123 is disposed below the second substrate 112. This batch is laminated.

In addition, outer circuits 135a and 135b are provided on an upper surface of the second prepreg layer 122 and a lower surface of the third prefrag layer 123, and an outer circuit provided on the upper surface of the second prepreg layer 122. An element 140 is then attached to 135a.

In this case, a via hole 133 is formed in the second prepreg layer 122 to thermally connect the element 140 and the heat pipe 130 to be attached to the outer layer circuit 135a.

The via hole 133 is formed by a laser, and the inner surface of the via hole 133 is plated with gold having good conductivity, so that the via hole 133 may be electrically conductive.

In addition, a conductive material 143 such as a conductive paste or a solder paste is applied to the lower portion of the device 140, which couples the device 140 to the outer circuit 135a, and the device 140 and the outer layer. It is for the electrical connection with the circuit 135a to be implemented.

2 to 9 are process diagrams for a method of manufacturing a printed circuit board according to the first embodiment of the present invention.

2 to 9, the method of manufacturing the printed circuit board 100 according to the first embodiment of the present invention is the same as the method of manufacturing the printed circuit board 100 having the same configuration as that of FIG. 1. Components that function have been given the same reference numerals, and redundant description will be omitted below.

First, as shown in FIGS. 2 and 3, first and second substrates 111 and 112 having circuits 111a and 112a formed on both surfaces thereof are prepared.

In addition, a first prepreg layer 121 is provided between the first substrate 111 and the second substrate 112 to increase insulation between the first substrate 111 and the second substrate 112. Thus, the first substrate 111, the second substrate 112 and the first prepreg layer 121 are collectively bonded and laminated.

Next, as illustrated in FIG. 4, a through hole 125 penetrating a predetermined region of the stacked first substrate 111, the second substrate 112, and the first prepreg layer 121 is formed. .

However, at this time, unlike the method described above, after the circuits 111a and 112a are formed on both surfaces and the through holes 125 are formed therein, the first substrate 111 and the second substrate 112 are prepared. A first prepreg layer 121 having a through hole 125 formed therethrough corresponding to the through hole 125 may be provided between the substrate 111 and the second substrate 112 to be bonded and stacked.

 In this case, the through hole 125 is a space in which the heat pipe 130 is built, and is formed by a drill or an NC router.

As such, when the through hole 125 is formed by the drill, it is preferable to further perform a desmear process of removing smear existing in the through hole 125 at the time of formation.

Next, as illustrated in FIG. 5, the heat pipe 130 is embedded in the through hole 125.

A fluid serving as a refrigerant and a micro flow path through which the fluid flows are formed in the heat pipe 130, and a wall of the heat pipe 130 is made of copper or aluminum.

6 and 7, a third prepreg layer 122 is disposed on the upper surface of the first substrate 111 having the heat pipe 130 embedded therein and a third prep is formed on the lower surface of the second substrate 112. The lag layer 123 is bonded and laminated.

The second prepreg layer 122 forms a via hole 133 exposing the top surface of the bottom pipe 130.

The via hole 133 is formed by a laser and the inner surface is plated with copper or gold to be electrically conductive.

Next, as illustrated in FIG. 8, outer circuits 135a and 135b are formed on an upper surface of the second prepreg layer 122 and a lower surface of the third pregraph layer 123, and the outer circuit 135a is formed. 135b) PSR is applied to the surface, and the surface treatment and appearance processing including exposure and development are performed.

Then, when the cotton paper or foreign matter is removed by high pressure washing, the printed circuit board 100 according to the first embodiment of the present invention is completed.

 Next, as shown in FIG. 9, the device 140 is attached to the outer layer circuit 135a formed on the upper surface of the second prepreg layer 122, that is, the via hole 133.

A printed circuit board and a manufacturing method thereof according to a second embodiment of the present invention will be described in detail with reference to FIGS. 10 to 18.

10 is a cross-sectional view of the printed circuit board 100 according to the second embodiment of the present invention.

Referring to FIG. 10, the printed circuit board 100 according to the second embodiment of the present invention may be divided into a first substrate 111, a second substrate 112, a first prepreg layer 121, and a second substrate. The prepreg layer 122, the third prepreg layer 123, and the heat pipe 130 in which metal materials 131a and 131b are bonded to both outer surfaces. It includes the outer circuit (135a, 135b).

Many surfaces of the first substrate 111 and the second substrate 112 are compressed by pressing a copper foil layer on both sides of a substrate such as phenol resin and epoxy resin, and then exposing, developing and etching the circuit. Patterns 111a and 111b are formed.

In addition, a first prepreg layer 121 is stacked between the first substrate 111 and the second substrate 112.

In this case, the first prepreg layer 121 serves to increase the insulation between the first substrate 111 and the second substrate 112.

A through hole 125 penetrating the first substrate 111, the second substrate 112, and the first prepreg layer 121 stacked as described above is formed, and the through hole 125 is drilled or It is formed by the NC router.

And the heat pipe 130 is built in the through-hole 125,

A fluid that acts as a refrigerant is injected into the heat pipe 130, and the fluid absorbs ambient heat in the process of repeating condensation and evaporation, and transfers heat by the flow of the fluid through a microchannel. . At this time, the wall of the heat pipe 130 is made of a copper or aluminum material.

In addition, metal materials 131a and 131b serving as dummy parts are bonded to both outer surfaces of the heat pipe 130, and one side surface 131a of the metal material bonded to the heat pipe 130 is the first. The substrate is protruded to the outside of the end side of the substrate and the second substrate so that the condensation portion of the heat pipe 130 contacts air in the air, thereby further improving thermal conductivity.

Next, a second prepreg layer 122 is stacked on the first substrate 111 having the heat pipe 130 embedded therein, and a third prepreg layer 123 is disposed below the second substrate 112. This batch is laminated.

In addition, outer circuits 135a and 135b are provided on an upper surface of the second prepreg layer 122 and a lower surface of the third prepreg layer 123, and an outer circuit circuit provided on an upper surface of the second prepreg layer 122. An element 140 is then attached to 135a.

In addition, the printed circuit board 100 includes a via hole 133 formed through the metal material 131a and 131b bonded to the heat pipe 130 including the first substrate and the second substrate. The device 140 and the heat pipe 130 are thermally connected.

In this case, the via hole 133 is formed by a drill, and the inner surface is plated, and an insulating material such as the prepreg layers 121, 122, and 123 is applied therein so that the via hole 133 may be electrically conductive.

A conductive material 143 such as a conductive paste or a solder paste is coated on the lower portion of the device 140, which couples the device 140 to the outer layer circuit 135a, and the element 140 and the outer layer circuit ( Electrical connection with 135a).

11 to 18 are flowcharts illustrating a method of manufacturing a printed circuit board according to the second embodiment of the present invention.

11 to 18, the method of manufacturing the printed circuit board 100 according to the second exemplary embodiment of the present invention is the same as the method of manufacturing the printed circuit board 100 having the same configuration as that of FIG. 10. Components that function have been given the same reference numerals, and redundant description will be omitted below.

First, as illustrated in FIGS. 11 and 12, first and second substrates 111 and 112 having circuits 111a and 112a formed on both surfaces thereof are prepared.

In addition, a first prepreg layer 121 may be provided between the first substrate 111 and the second substrate 112 to increase insulation between the first substrate 111 and the second substrate 112. Thus, the first substrate 111, the second substrate 112 and the first prepreg layer 121 are collectively bonded and laminated.

Next, as illustrated in FIG. 13, a through hole 125 is formed at an end side of the stacked first substrate 111, the second substrate 112, and the first prepreg layer 121.

However, at this time, unlike the above method, after the circuits 111a and 112a are formed on both surfaces, and the through holes 125 are formed therein, the first substrate 111 and the second substrate 112 are prepared. A first prepreg layer 121 having a through hole 125 formed therein corresponding to the through hole 125 is formed between the first substrate 111 and the second substrate 112 to be bonded and stacked. It may be.

In this case, the through hole 125 is a space in which the heat pipe 130 is built, and is formed by a drill or an NC router.

As such, when the through hole 125 is formed by the drill, it is preferable to further perform a desmear process for removing smear existing in the through hole 125 when forming the through hole 125.

Next, as illustrated in FIG. 14, the heat pipe 130 is embedded in the through hole 125.

The heat pipe 130 has a fluid that acts as a refrigerant and a micro flow path through which the fluid flows. The wall of the heat pipe 130 is made of copper or aluminum.

In addition, metal materials 131a and 131b serving as a dummy are bonded to both outer surfaces of the heat pipe 130, and one side surface 131a of the metal material when the heat pipe 130 is embedded in the through hole 125. ) May protrude outward from end portions of the first substrate 111 and the second substrate 112.

Then, as shown in FIGS. 15 and 16, a third prepreg layer 122 is disposed on the upper surface of the first substrate 111 having the heat pipe 130 embedded therein and a third prep is formed on the lower surface of the second substrate 112. The lag layer 123 is bonded and laminated.

The printed circuit board 100 includes the first substrate 111 and the second substrate 121 df to form a via hole 133 penetrating through the metal materials 131a and 131b bonded to the heat pipe. .

The via hole 133 is formed by a drill, and an inner surface of the via hole 133 is plated with copper or gold, and an insulating material such as the prepreg layers 121, 122, and 123 is applied therein to allow electrical conduction.

Next, as illustrated in FIG. 17, outer circuits 135a and 135b are formed on an upper surface of the second prefrag layer 122 and a lower surface of the third prefrag layer 123, and the outer circuits 135a and 135b are formed. ) PSR is applied to the surface, and surface treatment operations and appearance processing including exposure and development are performed.

next. Removing dust or foreign matter by high pressure washing is completed the printed circuit board 100 according to the second embodiment of the present invention.

Next, as shown in FIG. 18, the device 140 is attached to the outer circuit 135a formed on the upper surface of the second prepreg layer 122.

As such, the printed circuit board and the method of manufacturing the same according to the present invention have a heat conductivity for improving heat conductivity for dissipating heat generated from the device 140 to the outside by embedding the heat pipe 130 in the printed circuit board 100. Unlike the conventional method, the space utilization is improved by removing the heat sink attached to the device 140, thereby reducing the overall printed circuit board size and reducing the product cost.

Although the preferred embodiments of the present invention described above have been described in detail, those skilled in the art will understand that various modifications and equivalent other embodiments are possible therefrom.

Accordingly, the scope of the present invention is not limited to the disclosed embodiments, but various modifications and improvements of those skilled in the art using the basic concept of the present invention as defined in the following claims are also within the scope of the present invention.

1 is a cross-sectional view of a printed circuit board according to a first embodiment of the present invention.

2 to 9 are process diagrams for a method of manufacturing a printed circuit board according to the first embodiment of the present invention.

10 is a cross-sectional view of a printed circuit board according to a second exemplary embodiment of the present invention.

11 to 18 are flowcharts illustrating a method of manufacturing a printed circuit board according to the second embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

100: printed circuit board

111: first substrate 112: second substrate

111a, 112a: circuit pattern

121: first prepreg layer 122: second prepreg layer

123: third pre-frag layer 125: through hole

130: heat pipe 131a.131b: metal material

133: via hole 135a, 135b: external circuit

140 element 143 conductive material

Claims (19)

A first prepreg layer interposed between the first substrate and the second substrate and the first substrate and the second substrate, the circuit being formed on both surfaces; A through hole formed through the first prefrag layer bonded between the first substrate and the second substrate; A heat pipe embedded in the through hole; A second prepreg layer and a third prepreg layer stacked on the first substrate and the second substrate, respectively; An outer layer circuit provided on an upper surface of the second prepreg layer and a lower surface of the third prefrag layer; Printed circuit board comprising a. The method of claim 1, A printed circuit board having a coolant injected into the heat pipe and a fine flow path through which the coolant flows. The method of claim 1, The wall of the heat pipe is a printed circuit board made of copper or aluminum. The method of claim 1, The through hole is a printed circuit board formed by a drill or NC router. The method of claim 1, A printed circuit board having an element coated on a lower surface thereof with a conductive material attached to the outer layer circuit provided on the second prepreg layer. The method of claim 5, The conductive material is a printed circuit board made of a conductive paste or solder paste. The method of claim 5, And a via hole connecting the second prepreg layer to the outer circuit and the heat pipe. The method of claim 7, wherein The via is a printed circuit board formed by a laser. Preparing a first substrate and a second substrate having circuits formed on both surfaces thereof; Bonding and laminating a first prepreg layer between the first substrate and the second substrate; Forming a through hole penetrating the stacked first substrate, the second substrate, and the first prepreg layer; Embedding a heat pipe in the through hole; Bonding and stacking a second prepreg layer on an upper surface of the first substrate and a third prepreg layer on a lower surface of the second substrate; And Forming an outer layer circuit on an upper surface of the second prepreg layer and a lower surface of the third prepreg layer; Printed circuit board manufacturing method comprising a. The method of claim 9, After bonding and laminating a second prepreg layer on the first substrate and a third prepreg layer on the lower surface of the second substrate, And a via hole for electrically connecting the second prepreg layer and the element attached to the outer circuit and the heat pipe. The method of claim 9, After the step of forming an outer layer circuit on the upper surface of the second pre-frag layer and the lower surface of the third pre-frag layer, Applying PSR to the outer circuit surface, performing a surface treatment operation and appearance processing including the exposure and development, and attaching a device with a conductive material to the outer circuit formed on the second prepreg layer Printed circuit board manufacturing method further comprises. Preparing a first substrate and a second substrate having circuits formed on both surfaces thereof and through holes formed therein; It is provided between the first substrate and the second substrate, corresponding to the through hole Bonding and stacking the first prepreg layer having a through hole formed therein; Embedding a heat pipe in the through hole; Bonding and stacking a second prepreg layer on an upper surface of the first substrate and a third prepreg layer on a lower surface of the second substrate; And Forming an outer layer circuit on an upper surface of the second prepreg layer and a lower surface of the third prepreg layer; Printed circuit board manufacturing method comprising a. A first prepreg layer interposed between the first substrate and the second substrate and the first substrate and the second substrate, the circuit being formed on both surfaces; A through hole formed through the first prefrag layer bonded between the first substrate and the second substrate; A heat pipe embedded in the through hole and having a metal material bonded to both outer surfaces thereof; A second prepreg layer and a third prepreg layer stacked on the first substrate and the second substrate, respectively; An outer layer circuit provided on an upper surface of the second prepreg layer and a lower surface of the third prefrag layer; Printed circuit board comprising a. The method of claim 13, A printed circuit board having a coolant injected into the heat pipe and a fine flow path through which the coolant flows. The method of claim 13, One side of the metal material bonded to the heat pipe is protruded to the outside of the end side of the first substrate and the second substrate. The method of claim 13, The printed circuit board includes a via hole penetrating a metal material bonded to the heat pipe, including the first substrate and the second substrate. Preparing a first substrate and a second substrate having circuits formed on both surfaces thereof; Bonding and laminating a first prepreg layer between the first substrate and the second substrate; Forming a through hole in an end side of the stacked first substrate, the second substrate, and the first prepreg layer; A step of embedding a heat pipe in which metal materials are bonded to both outer surfaces of the through hole; Bonding and stacking a second prepreg layer on the first substrate and a third prepreg layer on the bottom surface of the second substrate; And Forming an outer layer circuit on an upper surface of the second prepreg layer and a lower surface of the third prepreg layer; Printed circuit board manufacturing method comprising a. The method of claim 17, After bonding and laminating a second prepreg layer on the first substrate and a third prepreg layer on the lower surface of the second substrate, The printed circuit board further comprises the step of forming a via hole through the metal material bonded to the heat pipe including the first substrate and the second substrate. The method of claim 17, After the step of forming an outer layer circuit on the upper surface of the second pre-frag layer and the lower surface of the third pre-frag layer, Applying PSR to the outer circuit surface, performing a surface treatment operation and appearance processing including the exposure and development, and attaching a device with a conductive material to the outer circuit formed on the second prepreg layer Printed circuit board manufacturing method further comprises.

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