KR20110092751A - Heat spreading printed circuit board and method of manufacturing the same - Google Patents

Abstract

PURPOSE: A heat discharge printed circuit board and a manufacturing method thereof are provided to discharge heat from a semiconductor chip in various directions by forming a thermally conductive via hole in a vertical direction and a thermally conductive insulation layer in a horizontal direction. CONSTITUTION: A dielectric layer(120) is formed on the lower side of a first copper layer(110). A resin layer(130) is formed on the lower side of the dielectric layer. A second copper layer(140) is formed on the lower side of the resin layer. A plating layer(150) is coated on the lower horizontal surface of the second copper layer. A dielectric via hole(160) vertically penetrates from the upper horizontal surface of the resin layer to the lower horizontal surface of the second copper layer.

Description

Heat dissipation printed circuit board and manufacturing method of heat dissipation printed circuit board {HEAT SPREADING PRINTED CIRCUIT BOARD AND METHOD OF MANUFACTURING THE SAME}

The present invention relates to a heat dissipation structure of an electronic circuit, and more particularly, to a heat dissipation printed circuit board having improved heat dissipation performance and a method of manufacturing the same.

Modern electronic devices require fast operating speeds and large power consumption. As the operation speed of the electronic device increases and the power consumption increases, the junction temperature of the semiconductor chip and the die increases, and as the junction temperature increases, the failure rate of the electronic device increases. The smaller the semiconductor chip components, the shorter the connection length and the higher the power density, which is necessary to dissipate the heat generated, which can lead to serious problems in the semiconductor chip.

Among the embodiments, the heat dissipation printed circuit board includes a first copper layer, an insulating layer, a resin layer, a second copper layer, a plating film, and a plurality of dielectric via holes. The first copper layer includes copper as a main material, and a circuit pattern layer having electrical conductivity is formed through each process. The insulating layer is composed of a dielectric material in which one kind of Al 2 O 3, BN, AlN, and PN, or an alloy thereof and an epoxy are mixed, and is formed under the first copper layer and has a horizontal thermal conductivity. The numerical layer is composed of a glass and epoxy mixture, is formed under the insulating layer and has an insulating property. The second copper layer is formed under the resin layer and is electrically insulated from the first copper layer by the resin layer. The plating film includes gold or silver and is coated on the horizontal surface under the second copper layer. The plurality of dielectric via holes have a plurality of cylindrical shapes penetrating in a vertical direction from an upper horizontal plane of the resin layer to a lower horizontal plane of the second copper layer, and have thermal conductivity in a vertical direction. Thermal conductivity of the insulating layer and the plurality of dielectric via holes is higher than that of the resin layer.

Among the embodiments, the heat dissipation printed circuit board includes a first copper layer, a resin layer, a second copper layer, and a plurality of dielectric via holes. The first copper layer includes copper as a main material, and a circuit pattern layer having electrical conductivity is formed through an etching process. The resin layer is composed of a glass and epoxy mixture, is formed under the first copper layer and has an insulating property. The second copper layer is formed under the resin layer and is electrically insulated from the first copper layer by the resin layer. The plurality of dielectric via holes may have a plurality of cylindrical shapes penetrating in a vertical direction from an upper horizontal plane of the resin layer to a lower horizontal plane of the resin layer, and may have thermal conductivity in the vertical direction. The thermal conductivity of the plurality of dielectric via holes is higher than that of the resin layer.

Among the embodiments, the method of manufacturing a heat dissipation printed circuit board includes the steps of (a) forming a resin layer comprising a mixture of glass and epoxy, (b) forming a copper layer on both top and bottom surfaces or bottom surfaces of the resin layer, (c) forming a plurality of cylindrical via holes penetrating the resin layer and the copper layer in a vertical direction; And inserting a dielectric having a higher thermal conductivity than the resin layer in the plurality of via holes, and (e) coating a plating film on a lower horizontal surface of the copper layer of the lower cross section.

Among the embodiments, the method of manufacturing a heat dissipation printed circuit board includes (a) forming a plurality of cylindrical via holes penetrating in a vertical direction from an upper horizontal plane of a resin layer comprising a glass and epoxy mixture to a lower horizontal plane of the resin layer. (B) inserting a dielectric having a higher thermal conductivity than the resin layer in each of the plurality of via holes, and (c) crimping a conductive copper foil to the upper or lower horizontal surface of the resin layer. To form a copper layer.

Among the embodiments, the method of manufacturing a heat dissipation printed circuit board includes (a) forming a plurality of cylindrical via holes penetrating in a vertical direction from an upper horizontal plane of a resin layer comprising a glass and epoxy mixture to a lower horizontal plane of the resin layer. (B) inserting a dielectric having a higher thermal conductivity than the resin layer in each of the plurality of via holes, and (c) electroplating or electroless plating on the upper or lower horizontal surface of the resin layer. Performing to form a copper layer.

1 is a block diagram showing a laminated structure of a heat dissipation printed circuit board according to a first embodiment.
2 is a block diagram showing a laminated structure of a heat dissipation printed circuit board according to a second embodiment.
3 is a block diagram showing a laminated structure of a heat dissipation printed circuit board according to a third embodiment.
4A and 4B are cross-sectional views of a resin layer showing an arrangement structure of a plurality of dielectric via holes.
5 is a flowchart illustrating a method of manufacturing the heat dissipation printed circuit board illustrated in FIGS. 1 and 2.
6 and 7 are flowcharts illustrating a method of manufacturing the heat dissipation printed circuit board shown in FIG. 3.

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.

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.

The term “and / or” should be understood to include all combinations that can be presented from one or more related items. For example, the meaning of "first item, second item and / or third item" may be presented from two or more of the first, second or third items as well as the first, second or third item It means a combination of all the items that can be.

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 an element is referred to as being "directly connected" to another element, it should be understood that there are no other elements 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 "include" or "have" refer to features, numbers, steps, operations, components, parts, or parts thereof described. It is to be understood that the combination is intended to be present, but not to 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.

For each step, the identifiers (e.g., a, b, c, ...) are used for convenience of description, and the identifiers do not describe the order of the steps, and each step is clearly contextual. Unless stated in a specific order, it may occur differently from the stated order. That is, each step may occur in the same order as specified, may be performed substantially simultaneously, or may be performed in the reverse order.

All terms used herein have the same meaning as commonly understood by one of ordinary skill in the art unless otherwise defined. Terms defined in commonly used dictionaries should be interpreted to be consistent with meaning in the context of the relevant art and can not be construed as having ideal or overly formal meaning unless expressly defined in the present application.

1 is a block diagram showing a laminated structure of a heat dissipation printed circuit board according to a first embodiment.

Referring to FIG. 1, the heat dissipation printed circuit board 100 according to the first embodiment may include a first copper layer 110, an insulating layer 120, a resin layer 130, a second copper layer 140, and a plating film. 150 and a plurality of dielectric via holes 160.

The first copper layer 110 includes copper as a main material. The first copper layer 110 has electrical conductivity, and a circuit pattern layer may be formed through an etching process.

For example, a portion of the first copper layer that is not a circuit pattern is melted away by chemical treatment, and remains as a copper layer of a portion where the circuit pattern is formed to make or move a wire through which electricity and a signal are moved. Or electronic components such as BLU (Back Light Unit).

In this case, the thickness of the first copper layer 110 may be about 5 micrometers or more and about 80 micrometers or less for effective signal transmission and heat dissipation.

The insulating layer 120 may be composed of a dielectric material in which one of Al 2 O 3, BN, AlN, and PN or an alloy thereof is used as the main material and epoxy is mixed therein. In this case, the ratio of epoxy to the main material may be about 20 percent or more and about 40 percent or less. Insulating layer 120 may be generally formed of a material and a method similar to the dielectric layer of the metal PCB.

The insulating layer 120 is formed under the first copper layer 110 and has thermal conductivity in the horizontal direction. As shown in FIG. 1, since the insulating layer 120 is formed to have a uniform thickness in the horizontal direction under the first copper layer 110 and the insulating layer 120 has thermal conductivity, a circuit of the first copper layer 110 is provided. Heat generated in a specific portion of the pattern or a specific mounting component may be transferred to the insulating layer 120 to effectively dissipate heat. In addition, since the insulating layer 120 is an electrically insulating material, the insulating layer 120 does not affect the signal of the circuit pattern of the first copper layer 110. In this case, the thickness of the insulating layer 120 may be about 10 micrometers or more and about 200 micrometers or less for effective heat dissipation. In this case, the thermal conductivity of the insulating layer 120 may be about 0.2 W / mK or more and 10 W / mK or less. The thickness of each layer constituting such a heat dissipation printed circuit board can be experimentally determined.

The resin layer 130 is composed of a glass and an epoxy mixture. According to an embodiment, the resin layer 130 may be formed by a flame retardant 4 (FR4) PCB material and a manufacturing method. The resin layer 130 is formed under the insulating layer and has insulation. The resin layer 130 may have a thickness of about 0.2 millimeters or more and about 3 millimeters or less.

The second copper layer 140 is formed below the resin layer 130. The first copper layer 110 and the second copper layer 140 are electrically insulated from the resin layer 130. The thickness of the second copper layer 140 may be about 5 micrometers or more and about 80 micrometers or less.

The plating film 150 includes gold and / or silver. The plating film 150 may be coated on the horizontal surface below the second copper layer 140. This coating acts as a barrier to prevent migration and can prevent oxidation of the copper layer. It also protects the board from mechanical damage that occurs while handling the board and identifies the solder location.

The plurality of dielectric via holes 160 may have a plurality of cylindrical shapes penetrating in a vertical direction from an upper horizontal plane of the resin layer 130 to a lower horizontal plane of the second copper layer 140. The plurality of dielectric via holes 160 has a vertical thermal conductivity, and the thermal conductivity of the insulating layer 120 and the plurality of dielectric via holes 160 is higher than that of the resin layer 130.

That is, since the resin layer 130 has a relatively low thermal conductivity, the heat flow in the vertical direction may be smoothly performed through the via holes 160 having a relatively high thermal conductivity. In addition, since the upper portions of the plurality of via holes 160 are in contact with the insulating layer 120, the horizontal heat flow through the insulating layer 120 and the vertical heat flow through the via holes 160 are combined. Can be effective in dissipating heat in various directions. The uniform arrangement of the plurality of dielectric via holes 160 on the horizontal plane will be effective for the emission.

2 is a block diagram showing a laminated structure of a heat dissipation printed circuit board according to a second embodiment.

2, the heat dissipation printed circuit board 200 according to the second embodiment may include a first copper layer 110, an insulating layer 120, a third copper layer 170, a resin layer 130, and a second layer. A copper layer 140, a plating film 150, and a plurality of dielectric via holes 160 are included.

The heat dissipation printed circuit board 200 of FIG. 2 is similar to the heat dissipation printed circuit board 100 of FIG. 1, but further includes a third copper layer 170 formed between the insulating layer 120 and the resin layer 130. . The thickness of the third copper layer 170 may be about 5 micrometers or more and about 80 micrometers or less. According to an embodiment, it may be used to form a separate internal circuit pattern inside the stacked structure of the third copper layer 170. Since the third copper layer 170 also has a higher thermal conductivity than the resin layer 130, similarly to the insulating layer 120, the thermal conductivity in the horizontal direction may be smooth.

3 is a block diagram showing a laminated structure of a heat dissipation printed circuit board according to a third embodiment.

Referring to FIG. 3, the heat dissipation printed circuit board 300 according to the third embodiment may include a first copper layer 310, a resin layer 320, a second copper layer 330, and a plurality of dielectric via holes 340. It includes.

The first copper layer 310 includes copper as a main material, and a circuit pattern layer having electrical conductivity is formed through an etching process. The resin layer 320 is made of a glass and epoxy mixture, is formed under the first copper layer 310 and has an insulating property. The second copper layer 320 is formed below the resin layer. The first copper layer 310 and the second copper layer 320 are electrically insulated by the resin layer 320.

The plurality of dielectric via holes 340 may have a plurality of cylindrical shapes penetrating in the vertical direction from the upper horizontal plane of the resin layer 320 to the lower horizontal plane of the resin layer 320. The plurality of dielectric via holes 340 have thermal conductivity in the vertical direction, and the thermal conductivity of the plurality of dielectric via holes 340 is higher than that of the resin layer.

In the method of processing the plurality of dielectric via holes 340, first, a hole is formed in the numerical layer 320, a dielectric or an insulator is inserted into the hole, and then a copper foil is bonded to both surfaces or the end surfaces of the numerical layer using a press device. And a hole is formed in the numerical layer 320 and a dielectric or an insulator is inserted into the hole, and then a copper layer is formed by performing electroless plating or electrolytic plating on both surfaces or end surfaces of the resin layer 320. Such a method may be used to form part of the laminate structure of FIGS. 1 and 2.

The heat dissipation printed circuit board of FIG. 3 prevents the plurality of via holes 320 from penetrating into the first copper layer 310 and the second copper layer 320 to thermally expand the resin layer 130 and the via holes 160. It is possible to reduce problems such as distortion due to coefficient difference. That is, in general, the thermal expansion coefficients of the resin layer 130 and the via holes 160 may be different, and thus the substrate may be deformed as the temperature of the substrate is increased. Can give Therefore, the plurality of via holes 320 are in contact with only the surfaces of the first copper layer 310 and the second copper layer 320, thereby deforming the substrate due to a difference in thermal expansion coefficient between the resin layer 130 and the via holes 160. Can reduce the problem of

4A and 4B are cross-sectional views of a resin layer showing an arrangement structure of a plurality of dielectric via holes.

4A and 4B, the plurality of dielectric via holes 160 may be disposed at uniform intervals on the horizontal plane. Diameters D1 and D2 of the plurality of dielectric via holes 160 may be about 0.075 millimeters or more and about 5 millimeters or less. An interval S1 of adjacent dielectric via hole pairs among the plurality of dielectric via holes 160 may be about 3 times or less than a diameter of the plurality of dielectric via holes 160. In one embodiment, the diameter D2 of the second dielectric via holes may be smaller than the diameter D1 of the first dielectric via holes. For example, the diameter D2 of the second dielectric via holes may correspond to the distance S1-D1 between adjacent pairs of first dielectric via holes for structural stability and effective heat dissipation of the substrate. Alternatively, the diameter D2 of the second dielectric via holes may be smaller than the distance S1-D1 between the pair of adjacent first dielectric via holes.

4A and 4B, when the area ratio of the via holes 160 in the cross-sectional area of the numerical layer 160 is too small, the thermal conductivity may be low, and when too large, the resin layer 130 and the via holes 160 may be formed. As there may be a problem such as distortion due to the difference in coefficient of thermal expansion, it may be necessary to select an appropriate value.

5 is a flowchart illustrating a method of manufacturing the heat dissipation printed circuit board illustrated in FIGS. 1 and 2.

1, 2, and 5, in order to manufacture a heat dissipation printed circuit board, first, a resin layer 130 including a glass and an epoxy mixture is formed (S510).

Thereafter, copper layers 170 and 140 are formed on both upper and lower surfaces or lower end surfaces of the resin layer 130 (S510). The heat dissipation printed circuit board 100 of FIG. 1 has a copper layer formed only on the lower horizontal plane of the resin layer 130, and the heat dissipation printed circuit board 200 of FIG. 2 is disposed on both the upper horizontal plane and the lower horizontal plane of the resin layer 130. The copper layer was formed.

In addition, a plurality of cylindrical via holes 160 penetrating the resin layer 130 and the copper layers 170 and 140 in the vertical direction are formed (S530). In one embodiment, the inner surface of the via holes 160 may be plated with copper (Cu), aluminum (Al) or silver (Ag).

Thereafter, the foil composed of the copper layer 110 and the insulating layer 120 is pressed on one surface (S540), and a pressure having a higher thermal conductivity than the resin layer is inserted into the via holes 160 by applying pressure on the foil. (S550). The foil is composed of a copper layer 110 and an insulating layer 120, the dielectric of the insulating layer 120 is inserted into the via holes 160 when heat and pressure is applied to the foil through a pressing process. In this case, the dielectric may include one of Al 2 O 3, BN, AlN, and PN, or an alloy thereof and an epoxy.

The heat dissipation printed circuit board 100 of FIG. 1 forms a heat dissipation printed circuit board by pressing the foil so that the upper horizontal plane of the resin layer 130 and the insulating layer 120 of the foil contact each other. 200 is a heat radiation printed circuit board formed by pressing the foil so that the upper horizontal surface of the copper layer 170 and the insulating layer 120 of the foil abut.

Thereafter, the plating film 150 is coated on the lower horizontal surface (S560). In one embodiment, the plating film 150 may be coated on the lower horizontal surface of the second copper layer 140, the plating film 150 may include gold and / or silver. This coating acts as a barrier to prevent migration and can prevent oxidation of copper. It also protects the board from mechanical damage that occurs while handling the board and identifies the solder location.

6 and 7 are flowcharts illustrating a method of manufacturing the heat dissipation printed circuit board shown in FIG. 3.

Referring to FIG. 6, a plurality of cylindrical vias penetrating in the vertical direction from the upper horizontal plane of the resin layer including the glass and epoxy mixture to the lower horizontal plane of the resin layer in order to manufacture the heat dissipation printed circuit board shown in FIG. 3. After forming holes (S610), inserting a dielectric having a higher thermal conductivity than the resin layer in each of the plurality of via holes (S610), and compressing the copper foil having electrical conductivity to the upper horizontal plane or the lower horizontal plane of the resin layer. A copper layer is formed (S630). In one embodiment, the inner face of the via holes may be plated with copper, aluminum or silver.

Referring to FIG. 7, the copper layer may be formed by performing electroplating or electroless plating on the upper horizontal plane or the lower horizontal plane of the resin layer (S730).

 The present invention 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, the scope of the present invention should not be understood as being limited thereby.

According to an embodiment, a heat dissipation printed circuit board may be formed from a LED, a BLU, or other semiconductor chip mounted on a printed circuit board including a horizontal thermal conductive insulating layer and a plurality of vertical thermal conductive via holes on a laminated structure. It can effectively release heat in various directions. Therefore, the device mounted on the heat dissipation printed circuit board according to the exemplary embodiment may enable more stable operation.

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.

Claims (8)

A first copper layer including copper as a main material and having a conductive circuit pattern layer formed through an etching process;
An insulating layer comprising one of Al 2 O 3, BN, AlN, and PN, or a dielectric mixed with an alloy thereof and an epoxy, formed under the first copper layer, and having a thermal conductivity in a horizontal direction;
A resin layer composed of a glass and epoxy mixture and formed under the insulating layer and having an insulating property;
A second copper layer formed under the resin layer and electrically insulated from the first copper layer by the resin layer;
A plating film including gold or silver and coated on a lower horizontal surface of the second copper layer; And
It has a plurality of cylindrical shape penetrating in the vertical direction from the upper horizontal plane of the resin layer to the lower horizontal plane of the second copper layer, and comprises a plurality of dielectric via holes having thermal conductivity in the vertical direction,
The thermal conductivity of the insulating layer and the plurality of dielectric via holes is higher than the thermal conductivity of the resin layer. The method of claim 1,
The thickness of the said 1st copper layer and the said 2nd copper layer is 5 micrometers or more and 80 micrometers or less,
The thickness of the said insulating layer is 10 micrometers or more and 200 micrometers or less, The thermal conductivity of the said insulating layer is 0.2 W / mK or more and 10 W / mK or less,
The thickness of the said resin layer is 0.2 millimeters or more and 3 millimeters or less, The heat-dissipation printed circuit board characterized by the above-mentioned. The method of claim 2,
And the diameter of the plurality of dielectric via holes is greater than or equal to 0.075 millimeters and less than or equal to 5 millimeters, and the spacing of adjacent pairs of dielectric via holes is three times or less than the diameter of the plurality of dielectric via holes. The method of claim 3,
And a third copper layer formed between the insulating layer and the resin layer and having a thickness of 5 micrometers or more and 80 micrometers or less. A first copper layer including copper as a main material and having a conductive circuit pattern layer formed through an etching process;
A resin layer composed of a glass and epoxy mixture and formed under the first copper layer;
A second copper layer formed under the resin layer and electrically insulated from the first copper layer by the resin layer;
Comprising a plurality of cylindrical shape penetrating in the vertical direction from the upper horizontal plane of the resin layer to the lower horizontal plane of the resin layer, and comprises a plurality of dielectric via holes having thermal conductivity in the vertical direction,
The thermal conductivity of the plurality of dielectric via holes is higher than the thermal conductivity of the resin layer. (a) forming a resin layer comprising a glass and epoxy mixture;
(b) forming a copper layer on both top and bottom surfaces or bottom surfaces of the resin layer;
(c) forming a plurality of cylindrical via holes penetrating the resin layer and the copper layer in a vertical direction;
(d) pressing a foil composed of a copper layer and an insulating layer on one surface, and applying heat and pressure on the foil to insert a dielectric having a higher thermal conductivity than the resin layer in the plurality of via holes; And
(e) a method of manufacturing a heat dissipation printed circuit board comprising coating a plating film on a lower horizontal surface of the copper layer of the lower section. (a) forming a plurality of cylindrical via holes penetrating in a vertical direction from an upper horizontal plane of the resin layer comprising a glass and epoxy mixture to a lower horizontal plane of the resin layer;
(b) inserting a dielectric having a higher thermal conductivity than the resin layer in each of the plurality of via holes; And
(c) pressing the conductive copper foil onto the upper horizontal plane or the lower horizontal plane of the resin layer to form a copper layer. (a) forming a plurality of cylindrical via holes penetrating in a vertical direction from an upper horizontal plane of the resin layer comprising a glass and epoxy mixture to a lower horizontal plane of the resin layer;
(b) inserting a dielectric having a higher thermal conductivity than the resin layer in each of the plurality of via holes; And
(c) forming a copper layer by performing electrolytic plating or electroless plating on the upper horizontal plane or the lower horizontal plane of the resin layer.

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