KR20120072689A - The radiant heat circuit board and the method for manufacturing the same - Google Patents

Abstract

PURPOSE: A heat sink circuit board and a manufacturing method thereof are provided to improve the thermal characteristics of a heating device by plating the outer surface of a heat sink slug formed on the underside of a pad including the heating device. CONSTITUTION: A first circuit pattern(125) is buried between first and second insulating plates(110,130). A second circuit pattern(190) is formed on the top and bottom of the first and second insulating plates. A plating layer(175) is formed in the inner wall of a heat dissipation hole passing through one side to the other side of the first and second insulating plates. A cooling fin(160) fills in the heat dissipation hole. A plating member fills in a groove formed between the cooling fin and the first and second insulating plates.

Description

The radiant heat circuit board and the method for manufacturing the same

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

Printed Circuit Boards (PCBs) are like copper on electrically insulating substrates.

Is formed by printing a circuit line pattern with a conductive material, and refers to a board immediately before mounting an electronic component. That is, it means the circuit board which fixed the mounting position of each component, and printed and fixed the circuit pattern which connects components to the flat surface surface, in order to mount many electronic elements of various types densely on a flat plate.

The printed circuit board is formed on a plurality of conductive patterns on the substrate according to the designed circuit pattern, so that high temperature heat is emitted according to the conductive pattern and the mounting device. In particular, a device such as a light emitting diode (LED) It will release considerable heat.

1 is a cross-sectional view showing a conventional circuit board.

Referring to FIG. 1, a conventional circuit board 1 includes an insulating plate 10, a circuit pattern portion 20 on which a conductive layer is patterned, and a heating element pad 25.

The circuit board 1 may use an epoxy-based insulating plate 10, may include a through hole 11 to which electronic components are connected, and a circuit pattern formed on the insulating plate 10. The portion 20 is formed of a conductive material.

The heating element pad 25 is formed on the same plane as the circuit pattern portion 20, and the heating element 30 is mounted on the pad 25, and the heating element 30 is connected to the circuit through the wire 35. It is electrically connected to the pattern portion 20.

The heating element 30 may be a light emitting diode (LED) or the like, and the heating element 30 emits severe heat. The heat emitted from the heat generating element 30 raises the temperature of the circuit board 1, causing problems in the malfunction and reliability of the heat generating element 30.

In this case, in the circuit board 1 of FIG. 1, heat emitted from the mounted heating element 30 may not be emitted to the outside due to interference of the insulating plate 10 including the resin.

The embodiment provides a heat dissipation circuit board having a new structure and a method of manufacturing the same.

The embodiment provides a heat dissipation circuit board having improved thermal efficiency and a method of manufacturing the same.

The heat dissipation circuit board according to the embodiment of the present invention includes a plurality of insulating layers, heat dissipation holes formed through one surface and the other surface of the plurality of insulating layers, and heat dissipation fins filling the heat dissipation holes.

In addition, the method of manufacturing a heat dissipation circuit board according to an embodiment of the present invention includes the steps of attaching a plurality of insulating plates, forming a heat dissipation hole penetrating through one surface and the other surface of the plurality of attached insulating plates, the formed And inserting a heat radiation fin into the heat radiation hole to bury the heat radiation hole.

According to the present invention, by forming a heat dissipation slug under the pad to which the heat generating element is attached, and plating the outer circumferential surface of the heat dissipating slug, the thermal characteristics of the heat generating element can be improved while increasing the reliability of the formed heat dissipating slug.

In addition, when the light emitting diode is used as a heat generating device due to improved thermal characteristics, the lifespan of the device may be increased and light efficiency may be increased.

1 is a cross-sectional view showing a conventional heat dissipation circuit board.
2 is a cross-sectional view illustrating a heat dissipation circuit board according to an exemplary embodiment of the present invention.
3 to 12 are cross-sectional views illustrating a method for manufacturing a heat dissipation circuit board according to an exemplary embodiment of the present invention.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

Throughout the specification, the terminology used is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. Or in the present application, the term "comprises" or "having" is intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, one or more other It should be understood that the features or numbers, steps, operations, components, parts or combinations thereof do not preclude the existence or possibility of addition.

In order to clearly illustrate the present invention in the drawings, thicknesses are enlarged in order to clearly illustrate various layers and regions, and parts not related to the description are omitted, and like parts are denoted by similar reference numerals throughout the specification .

Whenever a portion of a layer, film, region, plate, or the like is referred to as being "on" another portion, it includes not only the case where it is "directly on" another portion, but also the case where there is another portion in between. On the contrary, when a part is "just above" another part, there is no other part in the middle.

In the drawings, the thickness or size of each layer is exaggerated, omitted or schematically illustrated for convenience and clarity of description. In addition, the size of each component does not entirely reflect the actual size.

The present invention provides a circuit board including a heat dissipation structure in a circuit board using an insulated resin substrate.

Hereinafter, a heat dissipation circuit board according to an exemplary embodiment of the present invention will be described with reference to FIGS. 2 to 12.

2 is a cross-sectional view of a heat dissipation circuit board according to an exemplary embodiment of the present invention.

2, a heat dissipation circuit board 100 according to an exemplary embodiment of the present invention may include a first insulating plate 110, a second insulating plate 130, and first and second insulating plates 110 and 130. The first circuit pattern 125 and the first and second insulating plates 110 embedded in the gap; A second circuit pattern 190 formed on the upper and lower portions of the 130, and formed on an inner wall of the heat dissipation hole 140 passing through one surface and the other surface of the first and second insulating plates 110 and 130, respectively. A plating layer 175, a heat dissipation fin 160 to bury the heat dissipation hole 140, and a plating member 175 to bury a spaced groove formed between the heat dissipation fin 160 and the first and second insulating plates. It is configured by.

The first insulating plate 110 may be a supporting substrate of the heat dissipation circuit board 100 in which a single circuit pattern is formed, but as shown in FIG. 2, the heat dissipation circuit board 100 according to the embodiment of the present invention is Since the plurality of insulating plates have a plurality of laminated structures attached to each other, the first insulating plate 110 may have an insulating layer region in which one base circuit pattern 125 is formed among heat dissipating circuit boards having a plurality of laminated structures. it means.

The second insulating plate 130 protects the first circuit pattern 125 formed on the first insulating plate 110.

In this case, the first insulating plate 110 and the second insulating plate 130 means one insulating layer among a plurality of stacked structures, respectively, and the upper or lower portion of the first insulating plate 110, the second insulating A plurality of base circuit patterns may be continuously formed on the upper or lower portion of the plate 130.

The first and second insulating plates 110 and 130 may be thermosetting or thermoplastic polymer substrates, ceramic substrates, organic-inorganic composite material substrates, or glass fiber impregnated substrates, and may include an epoxy resin. It may include, alternatively may include a polyimide resin.

In this case, the first and second insulating plates 110 and 130 may include an epoxy-based insulating resin having a low thermal conductivity (about 0.2 to 0.4 W / mk). It may also contain a de-based resin.

A first circuit pattern 125 is formed between the first and second insulating plates 110 and 130. The first circuit pattern 125 is formed by patterning a conductive layer stacked on the first insulating plate 110.

The first circuit pattern 125 is formed of a material having high electrical conductivity and low resistance, and may be formed by patterning a copper foil, which is a thin copper layer, as a conductive layer.

The first and second insulating plates 110 and 130 include at least one hole.

At this time, the hole includes a heat radiation hole 140 for forming a heat radiation structure. The heat dissipation hole 140 may be formed by a laser.

In addition, although only one heat dissipation hole 140 is illustrated in the drawing, it will be apparent to those skilled in the art that a plurality of heat dissipation holes may be formed.

In addition, although only the heat dissipation hole 140 is illustrated in FIG. 2, a through hole (not shown) may be additionally formed to electrically penetrate an external device.

That is, the heat dissipation circuit board 100 may include a via hole for electrically connecting the first circuit pattern 125 embedded between the plurality of insulating plates 110 and 130 to the second circuit pattern 190 of the upper or lower portion. And not shown) and conductive vias (not shown). The via hole may be formed by a laser, and the cross section of the via hole may have a circular or rectangular shape according to design. In addition, the via hole may be formed to be inclined at a predetermined angle with respect to the insulating plate. Alternatively, the via hole may be vertically formed.

The heat dissipation fins 160 are embedded in the heat dissipation holes 140.

The heat dissipation fin 160 may be formed to include a metal having high thermal conductivity, for example, an alloy including copper, and may be formed of an alloy of copper and nickel. In addition, the heat dissipation fins 160 may be formed of an alloy including silver or aluminum, which are commonly used for plating.

At this time, the corner of the heat dissipation fin 160 may be formed to be curved. That is, it is formed to have a curved surface having a predetermined curvature at the corner of the heat radiation fins 160, so that the heat radiation fins 160 can be easily inserted into the heat radiation holes 140 later.

In addition, the shape of the heat dissipation fin 160 described above is only one embodiment of the present invention, the heat dissipation fin 160 may be formed in another shape.

A plating layer 155 is formed on an inner wall of the heat dissipation hole 140.

The plating layer 155 is formed before the heat dissipation fin 160 is inserted, and the metal layer is formed along the outer circumferential surfaces of the first and second insulating plates 110 and 130 on which the heat dissipation holes 140 are formed. Can be formed. At this time, the metal layer is formed by plating a metal selected from the group consisting of copper, silver, aluminum and alloys thereof.

The plating layer 155 is formed to ensure reliability of an electrical signal by flash plating, and is preferably formed to have a thickness satisfying 10 to 15 μm.

In this case, the plating layer 155 and the heat dissipation fin 160 are preferably formed of the same metal. That is, the plating layer 155 may be formed to include a metal having high thermal conductivity. For example, the plating layer 155 may be formed of at least one of an alloy including copper, an alloy including silver, and an alloy including aluminum.

A plating member 175 is formed between the first and second insulating plates 110 and 130 having the heat dissipation holes 140 and the inserted heat dissipation fins 160.

The plating member 175 is spaced apart between the plating layer 1150 formed on the first and second insulating plates 110 and 130 on which the heat dissipation holes 140 are formed and the inserted heat dissipation fin 160. Landfill.

In other words, since the edges of the heat dissipation fins 160 are curved, the portion of the plating layer 155 is exposed to the outside by the shape of the heat dissipation fins 160. Accordingly, the plating member 175 fills up the exposed plating layer 155 to increase the bonding force between the plating layer 155 and the inserted heat dissipation fin 160.

In addition, the heat dissipation fin 160 is preferably formed to have a smaller width than the formed heat dissipation hole 140.

That is, since the plating layer 155 is formed on the inner wall of the heat dissipation hole 140, the heat dissipation fin 160 is formed to have a smaller width than the heat dissipation hole 140, and the heat dissipation hole 140 in which the plating layer 155 is formed. ) So that it can be easily inserted.

Meanwhile, the heat dissipation reliability of the heat dissipation circuit board 100 is determined by the size of the heat dissipation fin 160.

That is, when the size is larger than the reference value of the heat dissipation fins 160, there is a problem that the heat dissipation fins 160 cannot be inserted into the heat dissipation holes 140. The reference value may correspond to the size of the heat dissipation hole 140 in which the plating layer 155 is formed. In addition, when the size of the heat dissipation fin 160 is smaller than the reference value, the heat dissipation fin 160 may be separated from the heat dissipation hole 140. In addition, when the size of the heat dissipation fin 160 corresponds to the reference value, the heat dissipation fin 160 may be completely inserted into the heat dissipation hole 140. However, since the insertion of the heat dissipation fins 160 is made by a simple fitting method, not a perfect bonding, the heat dissipation fins 160 may be separated by physical or chemical impacts during the pretreatment or a change in temperature and humidity.

Therefore, in the embodiment according to the present invention, the plating member 175 is formed between the first and second insulating plates 110 and 130 and the heat dissipation fin 160 to increase the bonding property of the heat dissipation fin 160. To improve heat dissipation reliability.

In addition, the plating member 175 is formed to include the same metal as the heat radiation fin (160). That is, the plating main material 175 may be formed to include a metal having high thermal conductivity, and for example, may be formed of at least one of an alloy including copper, an alloy including silver, and an alloy including aluminum. .

As described above, the heat dissipation circuit board 100 according to the present invention can increase the heat dissipation rate by forming a heat dissipation structure by inserting the heat dissipation fins 160 prepared in advance into the heat dissipation holes 140 formed in the plurality of insulating plates. By forming a plating member 175 to fill the spaced groove formed between the plurality of insulating plates and the heat dissipation fin 160, the bonding property of the inserted heat dissipation fin 160 may be improved.

Hereinafter, a method of manufacturing the heat dissipation circuit board of FIG. 2 will be described with reference to FIGS. 3 to 12.

3 to 12 are cross-sectional views illustrating a method for manufacturing the heat dissipation circuit board of FIG. 2.

First, as shown in FIG. 3, the conductive layer 120 is formed on the first insulating plate 110.

The first insulating plate 110 and the conductive layer 120 may be formed by thermocompression, and the temperature of thermocompression is determined according to the reaction temperature of the curing agent of the first insulation plate 110.

In addition, the conductive layer as described above may be further included in the lower portion of the first insulating plate 110, and the adhesion between the lower conductive layer and the first insulating plate 110 may be formed by thermocompression bonding.

The first insulation plate 110 may include an epoxy resin or a polyimide resin without using an expensive ceramic material having high thermal conductivity, and the conductive layer 120 may include copper having high electrical conductivity and low resistance. It may be copper foil which is a thin thin film to contain.

When the conductive layer 120 formed on the upper or lower portion of the first insulating plate 110 is a copper foil containing copper, a stacking structure of FIG. 3 may use a cupper clad laminate (CCL).

Next, as illustrated in FIG. 4, the conductive layer 120 formed on the upper or lower portion of the first insulating plate 110 is etched in a predetermined pattern to form the first circuit pattern 125.

In this case, the circuit pattern 125 may be formed by etching through a photolithography process or by performing a laser process to form a pattern directly with a laser.

In addition, the first circuit pattern 125 may be formed on the upper and lower portions of the first insulating plate 110, respectively. Alternatively, the first circuit pattern 125 may be formed only on the upper portion.

Next, as shown in FIG. 5, a second insulating plate 130 is formed on the first insulating plate 110 on which the first circuit pattern 125 is formed.

The second insulating plate 130 may be formed of a material having the same high thermal conductivity as that of the first insulating plate.

In this case, the second insulating plate 130 may be formed by applying a semi-cured resin on the first insulating plate 110 on which the first circuit pattern 125 is formed and then curing.

Next, as shown in FIG. 6, a heat dissipation hole 140 penetrating one surface of the first insulating plate 110 and the other surface of the second insulating plate 130 is formed.

More preferably, the heat dissipation hole 140 is formed through the lower surface of the first insulating plate 110 and the upper surface of the second insulating plate 130.

The heat dissipation hole 140 may be formed by removing the first insulating plate 110 and the third insulating plate 130 having the first circuit pattern 125 embedded therein by a physical processing method.

In this case, when the heat dissipation hole 140 is formed using a laser, inner walls of the first insulating plate 110 and the second insulating plate 130 may be opened using a YAG laser or a CO ₂ laser. . In addition, the heat dissipation hole 140 may be formed by drilling.

Next, as shown in FIG. 7, the first plating layer 150 covering the outer circumferential surfaces of the first insulating plate 110 and the second insulating plate 130 having the heat dissipation holes 140 are formed.

The first plating layer 150 is formed of a metal having high thermal conductivity satisfying a thickness of 10 to 15㎛, and the metal includes an alloy including copper, an alloy containing silver, an alloy containing aluminum, and the like. Can be.

In addition, the first plating layer 150 may be formed by electroless plating the above metal on the first insulating plate 110 and the second insulating plate 130. In this case, the first plating layer 150 is formed to ensure reliability of an electrical signal by flash plating.

Next, the heat dissipation fins 160 are buried in the heat dissipation holes 140 formed as shown in FIG. 8.

The heat dissipation fin 160 may be formed of a material having a high thermal conductivity having an area smaller than that of the heat dissipation hole 140.

More preferably, the heat dissipation fin 160 includes the same metal as the first plating layer 150, and the metal may include an alloy including copper, an alloy including silver, and an alloy including aluminum.

In addition, since the first plating layer 150 is formed on the inner wall of the heat dissipation hole 140, the area of the heat dissipation fin 160 is smaller than the area of the heat dissipation hole 140.

In addition, the corners of the heat dissipation fins 160 are formed to be curved, so that the heat dissipation fins 160 can be easily inserted into the heat dissipation holes 140.

In this case, the heat radiation fin 160 may be inserted by cutting the heat radiation fin 160 into the heat radiation hole 140 and applying heat and pressure.

In addition, the heat dissipation fin 160 may be manufactured to have an area smaller than the area of the heat dissipation hole 140 in advance, and the manufacture of the heat dissipation fin 160 may be performed by a mold or a laser cutting method. It may be a surface treated material such as etching.

Next, as shown in FIG. 9, the second plating layer (not shown) is formed on the outer circumferential surfaces of the first insulating plate 110 and the second insulating plate 130 on which the first plating layer 150 is formed, and the outer circumferential surface inserted into the heat dissipation hole 140. 170).

The second plating layer 170 may be formed by filling gaps formed between the first and second insulating plates 110 and 130 and the heat dissipation fin 160, and may include the same metal as the heat dissipation fin 160. have.

That is, the second plating layer 170 may be formed of at least one metal of an alloy containing copper, an alloy containing silver, and an alloy containing aluminum.

Next, a mask 180 is stacked below the first insulating plate 110 on which the first and second plating layers 150 and 170 are formed and on the second insulating plate 130.

The mask 180 may include a window for opening a portion of the second plating layer 170 and may be formed of a photoresist or a dry film.

In this case, the mask 180 may be selectively formed at a position where a circuit pattern is to be formed.

Next, as shown in FIG. 11, the first metal layer 150 and the second metal layer 170 exposed by the window are etched by the mask 180.

That is, a first plating layer formed on an inner wall of the heat dissipation hole 140, a second plating layer filling a spaced groove formed between the first and second insulating plates 110 and 130 and the heat dissipation fin 160; The first plating layer and the second plating layer other than the first plating layer and the second plating layer to be used as the second circuit pattern 190 are etched and removed.

In other words, the first plating layer 152 and the second plating layer 172 to be used as the second circuit pattern 190 are formed.

In addition, the plating layer 155 is formed on the inner wall of the heat dissipation hole 140 to ensure the reliability of the electrical signal.

In addition, a buried member 175 may be formed to fill a spaced groove formed between the first insulating plate 110 and the second insulating plate 130 and the heat dissipation fin 160.

In this case, the buried member 175 fills the separation groove, thereby increasing the reliability of the bonding property of the heat dissipation fin 160.

Next, as shown in FIG. 12, the mask 180 stacked on the first insulating plate 110 and the second insulating plate 130 is removed to expose the formed second circuit pattern 190.

As described above, the heat dissipation circuit board 100 according to the present invention can increase the heat dissipation rate by forming a heat dissipation structure by inserting the heat dissipation fins 160 prepared in advance into the heat dissipation holes 140 formed in the plurality of insulating plates. By forming a plating member 175 to fill the spaced groove formed between the plurality of insulating plates and the heat dissipation fin 160, the bonding property of the inserted heat dissipation fin 160 may be improved.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, It belongs to the scope of right.

100: printed circuit board
110, 130: insulation plate
125: 190: circuit pattern
140: heat dissipation hole
150, 170: plating layer
160: heat radiation fins
175: plating member

Claims (19)

A plurality of insulating layers;
Heat dissipation holes formed through one surface and the other surface of the plurality of insulating layers; And
A heat dissipation circuit board comprising a heat dissipation fin filling the heat dissipation hole. The method of claim 1,
And a first plating layer formed on an inner wall of the formed heat dissipation hole. The method of claim 1,
The plating layer is a heat radiation circuit board is formed to have a thickness that satisfies 10 ~ 15㎛. The method of claim 1,
Radiating circuit board is formed by the corners of the radiating fins are curved The method of claim 1,
And a plating member filling a spaced groove between the insulating layer and the heat dissipation fin. 6. The method of claim 5,
The plating member is a heat radiation circuit board formed by etching the plurality of insulating layers and the second plating layer deposited on the outer peripheral surface of the heat radiation fins. The method according to claim 6,
And a circuit pattern formed by etching the second plating layer formed above or below the plurality of insulating layers. 6. The method of claim 5,
And the heat dissipation fin and the plating member are made of the same metal. The method of claim 8,
The metal is a heat dissipation circuit board selected from an alloy containing copper, an alloy containing silver and an alloy containing aluminum. The method of claim 1,
The heat dissipation fin has a smaller area than the heat dissipation hole formed. Attaching a plurality of insulating plates;
Forming a heat dissipation hole penetrating one surface and the other surface of the plurality of insulating plates attached thereto; And
And embedding the heat dissipation fins into the heat dissipation holes to bury the heat dissipation holes. 12. The method of claim 11,
And forming a first plating layer surrounding outer circumferential surfaces of the plurality of insulating plates on which the heat dissipation holes are formed. 13. The method of claim 12,
The first plating layer is a manufacturing method of the heat radiation circuit board to be formed to have a thickness that satisfies 10 ~ 15㎛. 12. The method of claim 11,
The radiating fin is a manufacturing method of a radiating circuit board is formed by curved corners. 12. The method of claim 11,
The heat dissipation fin is a manufacturing method of a heat dissipation circuit board having a smaller area than the formed heat dissipation hole. The method of claim 14,
And forming a second plating layer surrounding an outer circumferential surface of the plurality of insulating plates and the inserted heat dissipation fins. 17. The method of claim 16,
Etching the formed second plating layer to bury a spaced groove formed between the plurality of insulating plates and the heat dissipation fins. 17. The method of claim 16,
The heat dissipation fin and the second plating layer are formed to include the same metal,
The metal is a method of manufacturing a heat dissipation circuit board is selected from an alloy containing copper and an alloy containing aluminum. 17. The method of claim 16,
And etching the second plating layer formed on at least one surface of the insulating plate to form a circuit pattern.

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