KR102040493B1 - Heat sinking apparatus for printed circuit board and method of manufacturing the same - Google Patents

Abstract

The heat dissipation device for a printed circuit board includes a printed circuit board including first and second perforated areas disposed diagonally, a heat source disposed in the first perforated area, a heat sink disposed in the second perforated area, and asymmetrical to each other. A first punching portion formed to vertically join the first and second heat transfer surfaces at a rear surface of the printed circuit board, the heat source is joined at an end portion of the first heat transfer surface, and an end portion of the second heat transfer surface; Including a heat dissipation pad coupled to the heat sink. Therefore, the heat dissipation device for the printed circuit board may increase the surface area of the heat dissipation pad coupled to the printed circuit board, thereby increasing the dissipation of heat generated in the printed circuit board.

Description

Heat sink for printed circuit board and manufacturing method thereof {HEAT SINKING APPARATUS FOR PRINTED CIRCUIT BOARD AND METHOD OF MANUFACTURING THE SAME}

The present invention relates to a heat dissipation technology for a printed circuit board, and more particularly, a heat dissipation device for a printed circuit board that can increase the surface area of the heat dissipation pad coupled to the printed circuit board to increase the dissipation of heat generated from the printed circuit board. And it relates to a manufacturing method thereof.

Printed Circuit Board is a circuit that makes electricity by drawing a circuit on a board without using wires when connecting circuits between parts of electronic products. Unnecessary copper foil is removed to form an electronic circuit. Recently, in order to further miniaturize, a laminated substrate in which several thin substrates are bonded together is used, and a flexible substrate in which a copper foil pattern is coated on a plastic film is also used.

In recent years, as electronic devices used in the field of electric and electronic products have been pursued to be lighter, thinner, smaller, and multifunctional, electronic devices have become highly integrated and generate more heat. It is a cause of malfunction, substrate deterioration, and the like. Accordingly, interest in technology for controlling the heat of release is increasing, and a composite material including a carbon material, a ceramic material or a high thermal conductive filler, and a polymer material is used as a heat dissipation material as a high heat dissipation circuit board material.

Korea Patent Publication No. 10-1263425 (2013.05.06) relates to a printed circuit board, in particular, the first metal layer for forming the electrical circuit pattern, and the second metal layer for forming the heat sink pattern on the base substrate It is a technical object of the present invention to provide a heat sink integrated printed circuit board and a method of manufacturing the same, in which an electric circuit pattern and a heat sink pattern are formed through the same etching process. To this end, the heat sink integrated printed circuit board manufacturing method according to the present invention comprises the steps of depositing a first metal layer and a second metal layer on both sides of the base substrate; Forming a mask pattern on each of the first metal layer and the second metal layer; And simultaneously etching an etching material onto the first metal layer and the second metal layer using the mask pattern as a mask to form an electric circuit pattern on the first metal layer, and forming a heat sink pattern on the second metal layer. And, copper is used as the first metal layer, and aluminum is used as the second metal layer.

Korean Patent Publication No. 10-0432715 (2004.05.13) relates to a printed circuit board having a heat dissipation member, a method of manufacturing the same, and a semiconductor package using the printed circuit board. The printed circuit board 80 of the present invention forms a plurality of circuit pattern layers on the alloy panel 10. The circuit pattern layer and the alloy panel 10 are electrically and thermally connected through the via hole 36. The chip 100 is directly seated on the heat sink panel 75 attached to one surface of the alloy panel 10. To this end, a cavity 82 is formed through the circuit pattern layer and the alloy panel 10. The heat sink panel 75 is formed on one surface of the cavity 82, and the chip 100 is seated thereon. According to the present invention, the ground layer can be relatively reduced, thereby reducing the overall height of the printed circuit board 80 and lowering the overall height of the package because the chip 100 is seated in the cavity 82. In addition, since the cavity 82 is formed without the heat sink panel 75 attached, the manufacturing process becomes easier and the cavity 82 may be more accurately formed.

1. Korean Registered Patent Publication No. 10-1263425 (2013.05.06) 2. Korean Patent Publication No. 10-0432715 (2004.05.13)

An embodiment of the present invention is to provide a heat dissipation device for a printed circuit board that can increase the dissipation of heat generated from the printed circuit board by increasing the surface area of the heat radiation pad coupled to the printed circuit board.

One embodiment of the present invention is to provide a heat dissipation device for a printed circuit board that can be manufactured to include a bend on the surface of the heat dissipation pad coupled to the printed circuit board to increase the heat dissipation surface to increase the effect of heat dissipation. .

One embodiment of the present invention is to provide a heat dissipation device for a printed circuit board that can increase the thermal conductivity and increase the cost competitiveness by manufacturing a heat dissipation pad coupled to a printed circuit board made of an alloy such as copper and aluminum.

In one or more embodiments, a heat dissipation device for a printed circuit board may include a printed circuit board including first and second perforated regions disposed diagonally, a heat source disposed in the first perforated region, and a heat disposed in the second perforated region. A sink formed to vertically couple the sink and the mutually asymmetrical first and second heat transfer surfaces at the rear surface of the printed circuit board, the heat source at the distal end of the first heat transfer surface, and the second heat And a heat dissipation pad coupled to the heat sink at an end portion of the transfer surface.

The heat dissipation pad may include a heat connection surface disposed between the first and second heat transfer surfaces and forming a convex polygon.

The heat connection surface may form a symmetrical pentagon around a contact point corresponding to a vertex of the convex polygon and virtually extending from each of the outlines of the first and second heat transfer surfaces.

The first and second heat transfer surfaces may form a length difference that is non-integer times mutually.

The heat dissipation pad may be made of copper foil and attached by soldering on the printed circuit board.

The heat dissipation pad may be attached by soldering to each of the heat source and the heat sink.

The heat dissipation pad may be formed to a predetermined thickness.

The heat dissipation pad may be formed with a curved surface.

The heat dissipation pad may be composed of copper and aluminum, and may have a weight ratio of 7: 3 to 6: 4.

The heat dissipation pad is composed of copper and aluminum, and may have a weight ratio of 7.4: 2.6 to 6.8: 3.2.

The heat dissipation pads may not be contacted through the metal wires therebetween in relation to the printed circuit board.

The heat sink may be embedded in a partial opening opened toward the rear surface of the printed circuit board.

The heat sink is composed of copper, aluminum and magnesium, and may have a weight ratio of 0.4: 0.3: 0.3.

Among the embodiments, a method of manufacturing a heat dissipation device for a printed circuit board includes (a) arranging a printed circuit board including first and second perforation regions disposed diagonally, (b) transferring first and second heats; Forming a heat dissipation pad of copper foil including a heat connection surface formed of convex polygon between the surfaces and the first and second heat transfer surfaces; and (c) a heat source disposed in the first perforated region; And soldering the heat sink disposed in the second perforation area and the heat dissipation pad to vertically couple the rear surface of the printed circuit board.

The disclosed technique can have the following effects. However, since a specific embodiment does not mean to include all of the following effects or only the following effects, it should not be understood that the scope of the disclosed technology is limited by this.

The heat dissipation device for a printed circuit board according to the exemplary embodiment of the present invention may increase the surface area of the heat radiation pad coupled to the printed circuit board, thereby increasing the dissipation of heat generated from the printed circuit board.

The heat dissipation device for a printed circuit board according to the embodiment of the present invention may be manufactured to include a bend on the surface of the heat radiating pad coupled to the printed circuit board to increase the surface area where heat is dissipated, thereby increasing the effect of heat dissipation.

In the heat dissipation device for a printed circuit board according to an embodiment of the present invention, a heat dissipation pad coupled to a printed circuit board may be made of an alloy such as copper and aluminum to increase thermal conductivity and increase price competitiveness.

1 is a view for explaining a heat radiation device for a printed circuit board according to an embodiment of the present invention.
FIG. 2 is a diagram illustrating a heat radiation pad attached to the printed circuit board of FIG. 1.
3 is a flowchart illustrating a manufacturing method of a heat dissipation device for a printed circuit board according to the present invention.

Description of the present invention is only an embodiment for structural or functional description, the scope of the present invention should not be construed as limited by the embodiments described in the text. That is, since the embodiments may be variously modified and may have various forms, the scope of the present invention should be understood to include equivalents capable of realizing the technical idea. In addition, the objects or effects presented in the present invention does not mean that a specific embodiment should include all or only such effects, the scope of the present invention should not be understood as being limited thereby.

On the other hand, the meaning of the terms described in the present application should be understood as follows.

Terms such as "first" and "second" are intended to distinguish one component from another component, and the scope of rights should not be limited by these terms. For example, the first component may be named a second component, and similarly, the second component may also be named a first component.

When a component is referred to as being "connected" to another component, it should be understood that there may be other components in between, although it may be directly connected to the other component. On the other hand, when a component is referred to as being "directly connected" to another component, it should be understood that there is no other component in between. On the other hand, other expressions describing the relationship between the components, such as "between" and "immediately between" or "neighboring to" and "directly neighboring to", should be interpreted as well.

Singular expressions should be understood to include plural expressions unless the context clearly indicates otherwise, and terms such as "comprise" or "have" refer to a feature, number, step, operation, component, part, or feature thereof. It is to be understood that the combination is intended to be present and does not exclude in advance the possibility of the presence or addition of one or more other features or numbers, steps, operations, components, parts or combinations thereof.

All terms used herein have the same meaning as commonly understood by one of ordinary skill in the art unless otherwise defined. Generally, the terms defined in the dictionary used are to be interpreted to coincide with the meanings in the context of the related art, and should not be interpreted as having ideal or excessively formal meanings unless clearly defined in the present application.

1 is a view for explaining a heat radiation device for a printed circuit board according to an embodiment of the present invention.

Referring to FIG. 1, the heat dissipation device 10 for a printed circuit board may include a printed circuit board 100 and a heat dissipation pad 200, and the printed circuit board 100 may include at least one perforation area. It may be combined with the heat radiation pad 200.

In one embodiment, the printed circuit board 100 is a circuit board in which many parts of various types are densely mounted on a plate made of an insulator, and the circuits connecting the parts are densely shortened and fixed on the surface of the insulator plate. A thin plate of copper or the like is attached to one side of the insulating plate, and then etched (corroded and removed, leaving only the circuit on the line) according to the wiring pattern of the circuit to form a necessary circuit and make holes for attaching and mounting the parts.

In an exemplary embodiment, the printed circuit board 100 may be a flexible printed circuit board having copper foil on a polyimide (PI) insulating film and may be applied to highly integrated slimming products such as mobile phones by minimizing product size. Flexible printed circuit boards (FPCBs) are flexible printed circuit boards that have copper foil on an insulating film with a very thin thickness. They are flexible and flexible and are used as core boards of electronic parts such as mobile phones, camcorders, PCs and digital cameras. have.

As the performance improvement of PCs and the spread of smart phones and tablets have been spreading, the miniaturization and slimming of digital devices are rapidly progressing, and the high integration of circuit elements is increasing. When the heat generated by the high-performance device is filled inside the electronic device, heat generation, ignition from the electronic device, the operation speed of the device is lowered, and a malfunction occurs. Accordingly, as a countermeasure against heat generation generated in the printed circuit board 100, a heat sink or a member for increasing the heat diffusion is provided or a material having high heat dissipation is used as a material laminated on the substrate or the printed circuit board 100.

In one embodiment, the printed circuit board 100 includes first and second perforation regions 110 and 120 arranged diagonally, the first perforation region 110 is connected to the heat source 115, The second punching area 120 is connected to the heat sink 125. Here, the heat source 115 may correspond to a point where heat is mainly generated in the printed circuit board 100, and the heat sink 125 may correspond to a point at which heat generated may be emitted.

In one embodiment, the heat dissipation pad 200 is a heat disposed between the first and second heat transfer surfaces 210 and 220 and the first and second heat transfer surfaces 210 and 220 formed asymmetrically with each other. The connection surface 230 may be included. The heat dissipation pad 200 may be coupled to the heat source 115 at an end portion of the first heat transfer surface 210 and may be coupled to the heat sink 125 at an end portion of the second heat transfer surface 220. have.

FIG. 2 is a diagram illustrating a heat radiation pad attached to the printed circuit board of FIG. 1. 2A is a view for explaining a heat radiation pad, and FIG. 2B is a view for explaining a cross section of the heat radiation pad attached to a printed circuit board.

Referring to FIG. 2, the heat dissipation pad 200 is disposed between the first and second heat transfer surfaces 210 and 220 and the first and second heat transfer surfaces 210 and 220 formed asymmetrically with each other. And a heat connection surface 230.

In one embodiment, the heat dissipation pad 200 has a heat connection surface disposed between the first and second heat transfer surfaces 210 and 220 and the first and second heat transfer surfaces 210 and 220 which are mutually asymmetric ( In the form of 230). Here, blanking is one of metal processing methods, and is a processing method in which a hole is cut in a specific shape on a flat plate.

In one embodiment, the heat connection surface 230 may be formed of convex polygons. Herein, the convex polygon corresponds to a convex polygon, and each interior angle is smaller than 180 degrees, and the extended line does not pass through the inside of the polygon even if it extends any side of the polygon. The heat connection surface 230 is disposed between the first and second heat transfer surfaces 210 and 220 and may be formed differently according to the design, but the maximum surface area for dissipating heat generated from the heat source 115 is increased. It may be formed to be curved to a specific curvature to have a.

In one embodiment, the heat connection surface 230 may form symmetry about an intersection point of the lines extending virtually in each of the outlines of the first and second heat transfer surfaces 210 and 220. More specifically, the heat connection surface 230 may form a symmetric pentagon with respect to the contact point corresponding to the vertex of the convex polygon. Here, the contact point corresponding to the vertex of the heat connection surface 230 may correspond to the point where the lines extending from each of the outlines of the first and second heat transfer surfaces 210 and 220 cross vertically.

In one embodiment, the heat connection surface 230 is not formed of symmetrical pentagons, but the lines extending from each of the outlines of the first and second heat transfer surfaces 210 and 220 are vertically intersected. It may be formed differently according to the shape of the opposite side corresponding to the side opposite to the point. For example, the heat connection surface 230 has an opposite side corresponding to a side opposite to a point where lines extending from each of the outlines of the first and second heat transfer surfaces 210 and 220 cross each other vertically. The shape and the area may be formed differently according to the degree of inclination, and the heat dissipation effect of the printed circuit board 100 may be increased when the heat connection surface 230 has a symmetrical shape of the pentagon.

In one embodiment, the first and second heat transfer surfaces 210, 220 may form a length difference of each other non-integer. The first heat transfer surface 210 may be coupled with the heat source 115 at the distal end, and the second heat transfer surface 220 may be coupled with the heat sink 125 at the distal end. Therefore, the length of the first heat transfer surface 210 may be longer than the length of the second heat transfer surface 220, and the heat generated from the printed circuit board 100 may be transferred more widely, thereby providing the effect of heat radiation. Can be increased.

In one embodiment, the first and second heat transfer surfaces 210 and 220 may form a length difference of 4.1: 1.9 to 3.7: 2.3. More specifically, when the difference between the lengths of the first and second heat transfer surfaces 210 and 220 is 3.8: 2.1 or 3.9: 2.2, heat generated from the printed circuit board 100 can be transmitted more widely, so that the effect of heat radiation Can be increased.

In one embodiment, the heat dissipation pad 200 may be made of copper foil and soldered to the printed circuit board 100. The heat dissipation pad 200 may be soldered and attached to each of the heat source 115 disposed in the first perforated region 110 and the heat sink 125 disposed in the second perforated region 120 of the printed circuit board 100. Can be.

In one embodiment, the heat dissipation pad 200 may be formed to a thickness of a predetermined size, and may include a curved surface. The heat dissipation pad 200 may be formed to have a predetermined thickness, but may be formed on the surface thereof to more effectively dissipate heat generated from the printed circuit board 100. For example, the heat dissipation pad 200 may include a bend, such as a v-type or s-type, on the surface thereof, and may be manufactured differently according to a design.

In one embodiment, the heat dissipation pad 200 may be made of copper (Cu) and aluminum (Al), and copper and aluminum may be manufactured to have a weight ratio of 7: 3 to 6: 4. Copper and aluminum have a thermal conductivity of 320 (W / m · K) and 196 (W / m · K), respectively, at room temperature (20 ℃), and are widely used as thermally conductive materials because they are inexpensive among metal materials except silver or gold. Used.

Table 1 shows the thermal conductivity according to the weight ratio of copper and aluminum.

Experimental Results of Thermal Conductivity According to Weight Ratio of Copper and Aluminum Weight ratio (copper: aluminum) 5: 5 6: 4 7: 3 8: 2 Thermal conductivity medium Prize the best medium

As shown in Table 1, the heat radiation pad 200 can be seen that the thermal conductivity is high when the copper and aluminum is manufactured to include a weight ratio of 7: 3 to 6: 4: 4, in this range heat radiation pad 200 ) Is preferred.

In one embodiment, the heat dissipation pad 200 may be manufactured such that copper and aluminum have a weight ratio of 7.4: 2.6 to 6.8: 3.2. The heat dissipation pad 200 has the highest thermal conductivity when manufactured by including copper and aluminum in a weight ratio of 7: 3 to 6: 4, and particularly, copper and aluminum have a weight ratio of 7.4: 2.6 to 6.8: 3. When manufactured to have the highest thermal conductivity, the temperature of the printed circuit board 100 is reduced by up to about 5 ℃ can also increase the heat dissipation effect. Accordingly, the heat radiation pad 200 is preferably manufactured in a range in which copper and aluminum have a weight ratio of 7.4: 2.6 to 6.8: 3.2.

In one embodiment, the heat dissipation pad 200 may be made of an alloy including copper, aluminum, and silver (Ag). Silver (Ag) has a thermal conductivity of 360 (W / m · K) at room temperature (20 ° C.) and corresponds to a material having the highest thermal conductivity among metal materials. The heat dissipation pad 200 differs in content of the silver composition based on 100 parts by weight of the total heat dissipation pad 200 in the order of the first heat transfer surface 210, the heat connection surface 230, and the second heat transfer surface 220. It may include. For example, the first heat transfer surface 210 may include 5 to 7 parts by weight of silver composition based on 100 parts by weight of the total heat dissipation pad 200, and the heat connection surface 230 may include the entire heat dissipation pad 200. It may comprise 4 to 6 parts by weight of the silver composition with respect to 100 parts by weight, and the second heat transfer surface 220 may include 3 to 5 parts by weight of silver composition based on 100 parts by weight of the total heat dissipation pad 200. . As a result, the content of the silver composition of the first heat transfer surface 210 directly connected to the heat source 115 may be the highest, thereby increasing the conductivity of heat generated.

In one embodiment, the heat dissipation pad 200 may not be contacted through metal wires therebetween in relation to the printed circuit board 100. Specifically, the heat radiation pad 200 may be attached to the region corresponding to the heat source 115 of the printed circuit board 100 and the region corresponding to the heat sink 125 of the printed circuit board 100 by soldering. The metal wire may not be disposed between the heat dissipation pad 200 and the printed circuit board 100.

3 is a flowchart illustrating a method of manufacturing a heat dissipation device for a printed circuit board according to the present invention.

The printed circuit board 100 including the first and second perforation regions 110 and 120 disposed diagonally may be disposed (step S310).

In one embodiment, the heat sink 125 may be formed embedded in the partial opening opened toward the rear surface of the printed circuit board 100. The heat sink 125 may correspond to a groove recessed to a predetermined depth on the rear surface of the printed circuit board 100, and may be connected to the second heat transfer surface 220 of the heat dissipation pad 200.

In one embodiment, heat sink 125 may be comprised of copper (Cu), aluminum (Al) and magnesium (Mg), and may be manufactured so that copper, aluminum and magnesium have a weight ratio of 0.4: 0.3: 0.3. have. The heat sink 125 may be connected to the second heat transfer surface 220 of the heat dissipation pad 200 so as to dissipate heat generated from the printed circuit board 100. It may be prepared to include gold (Au) or silver (Ag).

A heat dissipation pad of copper foil including a heat connection surface 230 formed of a convex polygon between the first and second heat transfer surfaces 210 and 220 and the first and second heat transfer surfaces 210 and 220. 200 may be punched out (step S320).

In one embodiment, the heat dissipation pad 200 may be made of an alloy comprising copper, aluminum or silver. The heat dissipation pad 200 may be punched out in a shape determined according to a design in a plate shape made of two copper foils containing different amounts of silver composition with respect to 100 parts by weight of the total heat dissipation pad 200. Specifically, one copper foil plate shape of the plate of the heat dissipation pad 200 may include 5 to 7 parts by weight of silver composition based on 100 parts by weight of the total heat dissipation pad 200, and the other copper foil plate shape may include the entire heat dissipation pad 200. It is manufactured to include 3 to 5 parts by weight of the silver composition with respect to 100 parts by weight to combine the two copper foil plate shape to produce a single plate shape, and can form the heat radiation pad 200 in a predetermined shape according to the design. As a result, the heat-dissipating pad 200 that is punched out is formed with respect to 100 parts by weight of the total heat-dissipating pad 200 in the order of the first heat transfer surface 210, the heat connection surface 230, and the second heat transfer surface 220. The content of the silver composition may be different.

The heat source 115 disposed in the first punching area 110 and the heat sink 125 and the heat dissipation pad 200 disposed in the second punching area 120 are soldered to each other to be perpendicular to the rear surface of the printed circuit board 100. Can be combined (step S330).

In one embodiment, the heat-dissipating pad 200 of the punched copper foil is a heat sink disposed in the heat source 115 and the second perforated region 120 disposed in the first perforated region 110 of the printed circuit board 100. Solder to each of the 125 may be attached to the back of the printed circuit board (100).

Although described above with reference to a preferred embodiment of the present invention, those skilled in the art will be variously modified and changed within the scope of the invention without departing from the spirit and scope of the invention described in the claims below I can understand that you can.

10: radiator for printed circuit board
100: printed circuit board 110: first perforation area
120: second perforation area 115: heat source
125: heatsink
200: heat dissipation pad 210: first heat transfer surface
220: second heat transfer surface 230: heat connection surface

Claims (14)

A printed circuit board including first and second perforation regions disposed diagonally;
A heat source disposed in the first perforation area;
A heat sink disposed in the second perforation area; And
The first and second heat transfer surfaces are asymmetrically formed so as to be vertically coupled to the rear surface of the printed circuit board, and the heat source is coupled to an end portion of the first heat transfer surface. It includes a heat dissipation pad coupled to the heat sink at the end portion of,
The heat dissipation pad
And a heat connection surface disposed between the first and second heat transfer surfaces and forming a convex polygon.
delete The method of claim 1, wherein the heat connecting surface
And a pentagon symmetrically extending around each of the outlines of the first and second heat transfer surfaces and symmetrically about a contact point corresponding to a vertex of the convex polygon.
4. The method of claim 3, wherein the first and second heat transfer surfaces are
A heat dissipation device for a printed circuit board, characterized by forming a length difference by a non-integer multiple of each other.
The method of claim 1, wherein the heat radiation pad
A heat dissipation device for a printed circuit board, which is made of copper foil and attached by soldering on the printed circuit board.
The method of claim 5, wherein the heat radiation pad
And a heat sink attached to each of the heat source and the heat sink.
The method of claim 5, wherein the heat radiation pad
Heat radiation device for a printed circuit board, characterized in that formed in a thickness of a predetermined size.
The method of claim 7, wherein the heat radiation pad
Heat dissipation device for a printed circuit board, characterized in that formed on the curved surface.
The method of claim 5, wherein the heat radiation pad
A heat dissipation device for a printed circuit board, comprising copper and aluminum, and having a weight ratio of 7: 3 to 6: 4.
delete The method of claim 1, wherein the heat radiation pad
And a heat dissipation device for a printed circuit board, wherein the heat dissipation device is not in contact with the printed circuit board through a metal wiring therebetween.
The heat sink of claim 1, wherein the heat sink is
Heat dissipation device for a printed circuit board, characterized in that the buried in the partial opening opening toward the rear of the printed circuit board.
13. The heat sink of claim 12, wherein the heat sink is
A heat dissipation device for a printed circuit board, comprising: copper, aluminum, and magnesium, and having a weight ratio of 0.4: 0.3: 0.3.
(a) disposing a printed circuit board including first and second perforation regions disposed diagonally;
(b) forming a heat dissipation pad of copper foil including a heat connection surface formed of a convex polygon between the first and second heat transfer surfaces and the first and second heat transfer surfaces; And
(c) soldering the heat source disposed in the first perforated area, the heat sink disposed in the second perforated area, and the heat dissipation pad, and vertically coupling the heat sink to the rear surface of the printed circuit board. Method of manufacturing a heat radiating device.

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