KR20200073009A - Heat Dissipating Printed Circuit Board and The Manufacturing Method thereof - Google Patents

Abstract

The present invention relates to a heat radiation structure-integrated printed circuit board capable of lightening a product and reducing the entire volume as well as solving heat radiation issues of a printed circuit board by using a flat part of a heat radiation structure as a board without using a separate board as well as forming a heat radiation structure by injecting or extruding pellets made of a carbon-based material having excellent thermal conductivity and emissivity, and a manufacturing method thereof. The heat radiation structure-integrated printed circuit board includes: a heat radiation structure made of a carbon-based material including 40-60 wt% of a carbon-based mixture material and 40-60 wt% of polymer resin with respect to the total weight; an electric conduction layer made of a conductor plate; and an insulation bonding layer formed on the upper surface of the heat radiation structure such that the electric conduction layer is attached to the heat radiation structure. The carbon-based mixture material comprises: a carbon material dispersant including a solvent and at least one kind of carbon material selected from a group comprising a carbon nanotube, graphene and carbon black; and a graphite material comprising at least two kinds selected from a group comprising vein graphite, expanded graphite, flat graphite and spheroidal graphite.

Description

Heat dissipating printed circuit board and the manufacturing method thereof

The present invention relates to a carbon-based heat dissipation structure integrated printed circuit board and a method for manufacturing the same, and more specifically, to form a heat dissipation structure by injection or extrusion molding a pellet made of a carbon-based material having excellent heat conductivity and emissivity, and a separate substrate. It relates to a heat-radiating structure-integrated printed circuit board and a method of manufacturing the same to solve the heat generation problem of the printed circuit board by using the flat portion of the heat-radiating structure as a substrate without using and to reduce the overall volume and reduce the weight of the product.

In general, various types of heat sinks are used in household or industrial electronic devices. In the case of a computer, high heat is generated while a high-speed operation is performed in a CPU (Central Processing Unit), so a heat dissipation structure such as a cooling plate or a heat sink for cooling it is necessarily installed, and a printed circuit for forming circuits of various electronic devices A heat dissipation structure is also attached to the substrate. In particular, even in the case of an LED (Light Emitting Diode) lighting device widely used for lighting in recent years, since heat is generated according to the operation of the lighting circuit, a heat dissipation structure is mounted on the printed circuit board.

Printed Circuit Board (Printed Circuit Board) is a circuit that connects these electronic components as well as various electronic components are mounted on the surface of the substrate formed of an insulating material, and is commonly referred to as a'PCB'. As the development of the electronics industry, such printed circuit boards are required to speed up and increase the density of the circuits. Therefore, the printed circuit boards need to solve problems such as fine circuitization, high functionality, high reliability, and excellent electrical properties.

In addition, a semiconductor element such as an IC (integrated circuit) or a TR (transistor) and a heating element such as a light emitting diode are mounted on the printed circuit board, and a lot of heat is generated in the course of their operation. Particularly, in the case of an optical element such as a light emitting diode, very much heat is generated. Therefore, if the heat dissipation is not smoothly performed on the circuit board on which the heating element is mounted, the temperature of the printed circuit board itself increases, thereby causing malfunction and inoperability of the heating element, and acting as a factor that deteriorates product reliability. .

Therefore, the heat dissipation problem is solved by attaching a separate heat dissipation structure to the printed circuit board made of an insulating material such as plastic or metal such as aluminum, and, in some cases, an aluminum plate material or engineering constituting the printed circuit board. The heat dissipation is performed by directly coating the heat-radiating functional paint on the plastic, or when the substrate is formed by the extrusion method, the heat-radiating functional paint is coated on the aluminum plate or the extruder.

However, since the heat dissipation structure made of metal installed on the printed circuit board is heavy, it is hindering the weight reduction of the printed circuit board, and as the printed circuit board and the heat dissipation structure are formed in separate structures, the heat dissipation structure is attached to the printed circuit board. There is a problem in that installation is required.

On the other hand, as a result of investigating the prior art related to the present invention, a number of patent documents have been searched, and some of them are as follows.

Patent Document 1, the carbon nanotubes and metal base elements through a pre-treatment process, the carbon nanotubes and the metal base elements are covalently bonded to the metal as a method of further dissolving it in the corresponding metal, and then using the composite material to heat By constructing a sink, a heatsink composed of a composite material having a covalently bonded carbon nanotube, which has a mechanical strength as large as steel and can reduce the weight of the product to be mounted by reducing the weight by 20% or more, is disclosed. .

Patent Literature 2 includes a dispersion liquid containing a surface-modified carbon material, a heat-resistant additive, and an adhesive-enhancing emulsion, and has excellent heat dissipation performance and can be applied to various industrial fields requiring temperature control. Disclosed is a coating composition.

Patent Document 3, by forming a structure in which graphene is bonded in a direction orthogonal to the longitudinal direction of the carbon nanotubes, carbon that can improve the thermal conductivity and electrical conductivity of the existing longitudinal direction in the length and width direction as well. Disclosed is a heat sink composed of a nano-graphene composite material.

Patent Document 4, by crushing and mixing the high-conductivity carbon composite material and aluminum powder into fine particles through the primary ball milling step and the secondary ball milling step, and at the same time securing the dispersibility of the carbon composite material through the dispersing step Disclosed is a heat dissipation material using a carbon composite material capable of inducing light weight production by reducing volume and volume while simultaneously having excellent thermal conductivity as compared to a conventional aluminum heat sink, and a method of manufacturing the same.

Patent Document 5, by replacing the material of the heat dissipation body and heat dissipation assembly with a carbon nanotube heat dissipation material instead of conventional aluminum, it is possible to significantly increase the thermal conductivity, heat dissipation rate and heat dissipation rate, and the heat dissipation assemblies slide on the outer surface of the heat dissipation body It can be easily inspected and replaced by being configured to be attached in such a way, and the heat exchanger assembly of the heat dissipation assembly that is brought into contact with the LED substrate is formed to be spaced apart from each other, so that heat exchange is made more active and the heat dissipation efficiency is further increased. When the carbon nanotube heat dissipation material is manufactured, the carbon composite material with high thermal conductivity and the metal powder are crushed and mixed into fine particles through the primary ball milling step and the secondary ball milling step. By ensuring dispersibility, it is superior in thermal conductivity compared to conventional aluminum, and at the same time, it is possible to induce lighter weight production by reducing volume and volume, and to reduce production cost. Disclosed is a heat radiating frame for a lighting device.

KR 10-2010-0008733 A KR 10-2012-0013914 A KR 10-2017-0000220 A KR 10-2017-0068865 A

The present invention is to solve the above-mentioned problems of the prior art, by injection or extrusion molding a pellet made of a carbon-based material having excellent thermal conductivity and emissivity to form a heat dissipation structure and a flat surface of the heat dissipation structure without using a separate substrate. The purpose of the present invention is to provide a heat-radiating structure-integrated printed circuit board and a method of manufacturing the same to solve the heat generation problem of the printed circuit board by utilizing the portion as a substrate, and to reduce the overall volume and lighten the product.

The heat-radiating structure-integrated printed circuit board of the present invention for achieving the above object is formed of a carbon-based material containing 40 to 60% by weight of a carbon-based mixed material and 40 to 60% by weight of a polymer resin based on the total weight. A heat dissipation structure; An electrical conductive layer formed of a conductor plate so that a circuit can be formed; And an insulating bonding layer formed on an upper surface of the heat dissipation structure so that an electric conductive layer is attached to the heat dissipation structure. The carbon-based mixed material includes a carbon material dispersion and a graphite material, and the carbon material dispersion is carbon. Nanotubes, graphene and carbon black and one or more carbon materials and solvents selected from the group consisting of, and the graphite material is two or more selected from the group consisting of impression graphite and expanded graphite, plate graphite, spheroidal graphite It is characterized by being made.

Further, according to the printed circuit board integrated with the heat dissipation structure of the present invention, the carbon-based material for forming the heat dissipation structure further includes 1 to 5% by weight of an anti-degradation agent and an antioxidant for preventing decomposition of the polymer by ultraviolet rays. , The decomposition inhibitor is a group consisting of hydroxybenzophenone, hydroxyphenyl benzotriazole, arylester, oxanilides, formamidine It is made of at least one selected from, and the antioxidant is characterized in that it consists of at least one selected from the group consisting of phenol-based antioxidants, phosphorus-based antioxidants, sulfur-based antioxidants, amine-based antioxidants.

In addition, according to the integrated circuit board of the heat dissipation structure of the present invention, the heat dissipation structure is characterized in that it consists of a flat surface portion on which an insulating bonding layer is formed and a rear surface portion formed in an uneven shape to increase the heat dissipation area. .

And, the manufacturing method of the integrated circuit board of the heat dissipation structure of the present invention, based on the total weight of 40 to 60% by weight of the carbon-based mixed material and 40 to 60% by weight of a polymer-based pellet comprising a polymer resin A heat radiation structure forming step of forming a heat radiation structure by injection or extrusion; An insulating bonding sheet and an electrically conductive layer are sequentially stacked on the surface portion of the heat dissipation structure, followed by hot pressing for 2 to 3 hours at a pressure of 25 to 35 kgf/cm 2 and a temperature of 150 to 230° C. and cooling for 1 hour. A bonding step of turning on the electrically conductive layer to attach to the heat dissipation structure; A circuit printing step of front-treating the surface of the electrically conductive layer to print the circuit and dry it for 30-40 minutes at a temperature condition of 160-230°C; An etching step of etching the electrical conductive layer so that all parts except the circuit are removed by photosensitive treatment using a photoresist and a mask; A PSR printing step of printing an insulating reflective layer (PSR) on the electrically conductive layer remaining on the circuit and drying it for 30-40 minutes at a temperature condition of 170-180°C; It is characterized in that it comprises a; after the front-end processing to perform marking printing and drying for 30-40 minutes at a temperature condition of 150-170°C.

In addition, according to the manufacturing method of the integrated circuit board of the heat dissipation structure of the present invention, the bonding step is arranged in a form in which the concavo-convex portions of the rear surface engage a pair of heat dissipation structures having a flat surface portion and an uneven surface rear portion. After that, the insulation bonding sheet, the electric conductive layer, and the protective film are sequentially stacked from the flat part of each heat dissipation structure, and 2 or 4 stages are protected and separated by placing protective plates made of aluminum or stainless steel on top and bottom respectively. After lamination and lay-up, the initial pressure was applied in a vacuum heat press at a pressure of 5 to 10 kgf/cm 2 until 150° C. for 5 to 15 minutes, and secondly 150 to a pressure of 25 to 35 kgf/cm 2 After performing lamination bonding to apply temperature and pressure in a vacuum hot press for 110 to 150 minutes at a temperature condition of 230°C, cool it for 60 to 90 minutes while applying a pressure of 5 to 10 kgf/㎠ at a temperature of 20 to 40°C. It is characterized by being made in a manner.

The heat-radiating structure-integrated printed circuit board of the present invention and a method for manufacturing the heat-radiating structure are formed by extruding or extruding a pellet made of a carbon-based material having excellent thermal conductivity and emissivity to form a heat-radiating structure without using a separate substrate. By utilizing as a substrate, there is an effect of solving the heat generation problem of the printed circuit board and reducing the overall volume and making the product lighter.

In addition, according to the heat dissipation structure-integrated printed circuit board of the present invention and its manufacturing method, when forming a carbon-based material to form a heat dissipation structure used as a substrate, crushing and homogenizing the graphite material and the carbon material to have a homogeneous particle size distribution By impregnating a binder such as a polyamide resin to form a carbon-based material, the carbon material maintains a covalent bond between graphite materials, thereby exhibiting excellent heat dissipation performance and improving moldability.

In addition, according to the heat dissipation structure-integrated printed circuit board of the present invention and its manufacturing method, a heat dissipation structure is formed using a carbon-based material composed of a binder such as a carbon material and a polyamide resin, and is formed of metal by using it as a substrate. It has a remarkably light weight compared to the heat dissipation structure and the substrate, and it is possible to slim and lighten by using excellent moldability, and has the effect of significantly improving the thermal conductivity and heat dissipation performance.

1 is a configuration diagram showing a heat-radiating structure integrated printed circuit board according to the present invention.
Figure 2 is a reference diagram showing a state at the time of lay-up for lamination of a heat-radiating structure-integrated printed circuit board according to the present invention.
Figure 3 is a flow chart showing a method of manufacturing a heat dissipation structure integrated printed circuit board according to the present invention.
Figure 4 is a process diagram showing the manufacturing process of the integrated heat-dissipating printed circuit board according to the present invention.
Figure 5 is a flow chart showing the lay-up and shipping process of the integrated circuit board of the heat dissipation structure according to the present invention.

Hereinafter, with reference to the accompanying drawings, a description will be given of a heat-dissipating structure integrated printed circuit board of the present invention and its manufacturing method.

1 is a block diagram showing a printed circuit board integrated with a heat dissipation structure according to the present invention, and FIG. 2 is a reference view showing a state of layup for lamination of a printed circuit board integrated with a heat dissipation structure according to the present invention. And, Figure 3 is a flow chart showing a method of manufacturing a heat-dissipating structure-integrated printed circuit board according to the present invention, Figure 4 is a process chart showing the manufacturing process of a heat-dissipating structure-integrated printed circuit board according to the present invention, Figure 5 is the present invention It is a flow chart showing the layup and shipping process of the heat dissipation structure integrated printed circuit board.

A printed circuit board integrated with a heat dissipation structure according to the present invention includes a heat dissipation structure 100, an insulating bonding layer 200, an electric conductive layer 300, and a protective film 400, as shown in FIGS. 1 and 2.

The heat dissipation structure 100 is formed of a carbon-based material, the surface portion 110 in a flat form on which the insulating bonding layer 200 is seated, and the rear surface portion 120 formed in an uneven shape to increase the heat dissipation area Is made of 2, when stacking a plurality of heat dissipating structures 100, as shown in FIG. 2, the uneven parts of the back surface are interlocked to reduce the stacking height, and after stacking a plurality of printed circuit boards, hot It is intended to facilitate lay-up that enables simultaneous bonding operations through press operations.

At this time, the carbon-based material for forming the heat dissipation structure 100 is made of 40 to 60% by weight of the carbon-based mixed material and 40 to 60% by weight of the polymer resin based on the total weight.

The carbon-based mixed material includes a carbon material dispersion and a graphite material, and the carbon material dispersion includes at least one carbon material and a solvent selected from the group consisting of carbon nanotubes, graphene, and carbon black. In addition, the graphite material is composed of two or more types selected from the group consisting of impression graphite, expanded graphite, plate-like graphite, and spherical graphite. In addition, the polymer resin is made of polyamide resin or polyphenylene sulfide as a binder.

The carbon material dispersion is formed by crushing and homogenizing one or more carbon materials selected from the group consisting of carbon nanotubes, graphene, and carbon black, and then dispersing them in a solvent.

The crushing and homogenization of the carbon material is such that the carbon material in a raw material state having a heterogeneous particle size distribution is crushed to have a homogeneous particle size distribution, and is crushed and homogenized using a physical method or liquid nitrogen. And, the step of crushing and homogenizing the carbon nanotubes is also preferably repeated until a graphite material having a desired particle size and a uniform particle size distribution can be obtained.

At this time, the particle size of the carbon material is appropriately selected in consideration of the specific characteristics or process conditions and working environment of the heat dissipation structure, which is a final product, and crushing and homogenization are repeatedly performed until the particle size of the carbon material becomes 20 to 500 nm. It is desirable to do. When the particle size of the carbon material is less than 20 nm, agglomeration is difficult to occur, and when it exceeds 500 nm, it is not suitable because it is difficult to uniformly disperse the carbon material in a subsequent process as agglomeration has already occurred.

Among the carbon materials, the carbon nanotube is a helical material having a hexagonal structure in which six carbon atoms form a hexagonal shape, followed by a tube shape, and has a three-dimensional structure. The carbon nanotube is a modified form of graphite, and a single-walled carbon nanotube in which one layer of graphite is pushed in a tube shape and a multi-walled carbon nanotube composed of multiple layers (multi- wall Carbon Nanotube). These carbon nanotubes have excellent kinematic characteristics, and have a very high aspect ratio (length/diameter), so they have excellent tensile stress and excellent thermal conductivity. In addition, it has the properties of a conductor or a semiconductor according to a wound form, an energy gap varies depending on a diameter, and it has a three-dimensional structure and a quasi-one-dimensional structure, thus exhibiting a unique quantum effect. In addition, the most important thermal property of the carbon nanotube is that the thermal conductivity is very high at 6,600 W/mK, and it is known that the average free path of the phonon is due to a very large one.

And, when the above-described carbon material is mixed with the graphite material in a subsequent process, the carbon material is connected by covalent bonding between the graphite materials, thereby improving thermal conductivity and exerting excellent heat dissipation performance.

Subsequently, the crushed and homogenized carbon material is dispersed in a solvent to form a carbon material dispersion. That is, the crushed carbon material is dispersed in a solvent to a content of 2 to 20% by weight based on the total weight of the dispersion. At this time, the solvent may be made of one or more selected from the group consisting of distilled water, alcohol, dimethylformamide (DMF), methyl ethyl ketone (MEK) and polyol, and various process conditions such as sedimentation and long-term properties, material cost, manufacturing environment, etc. Choose appropriately considering.

In forming the carbon material dispersion, the carbon material is contained in an amount of 2 to 20% by weight based on the total weight of the dispersion, which does not cause a dispersibility problem when the content of the carbon material is less than 2% by weight, but graphite in a subsequent process When mixed with materials, the properties of thermal conductivity and heat dissipation cannot be exhibited, and when the content of the carbon material exceeds 20% by weight, there is a fear that dispersibility may occur and further effects can be expected to increase as the content increases. Because there is no.

The preparation of the carbonaceous dispersion may use one or more methods selected from the group consisting of ultrasonic, roll milling, ball milling, jet milling, screw mixing, attrition milling, bead milling, basket milling, idle rotation mixing and supermilling. That is, specific operating conditions and the like in each method used in manufacturing the carbon material dispersion are appropriately selected to form a uniform dispersion.

In addition, when manufacturing a carbon material dispersion, for improving the dispersibility of the carbon material, process convenience, and the like, if necessary, a kind of a dispersing agent, a neutralizing agent, and an antifoaming agent may be added. And, after the carbon material dispersion forming step, the carbon material dispersion may be dried at a temperature of 50 to 70° C. for 12 to 36 hours.

The above-described graphite material has high thermal conductivity, excellent mechanical properties and corrosion resistance, and has light properties, so that it can exhibit excellent performance when used as a material for heat dissipation structures and printed circuit boards. Then, by crushing and homogenizing the graphite material, the graphite material in a raw material state having an inhomogeneous particle size distribution has a homogeneous particle size distribution. As such, as the particle size distribution of the graphite material is uniformly controlled, the thermal conductivity and heat dissipation performance by the graphite material are greatly improved.

When the graphite material is crushed and homogenized, it may be performed using a conventional physical method, but it may also be performed using liquid nitrogen. That is, the graphite material can be crushed and homogenized by allowing liquid nitrogen to flow into the container containing the graphite material and then leaving it for about 30 minutes to 2 hours. This is the use of the finely crushed graphite material in the process of vaporization after the liquid nitrogen is impregnated in the graphite material. In addition, when crushing and homogenizing the graphite material, it is preferable to repeatedly perform crushing and homogenization until a graphite material having a desired particle size and uniform particle size distribution can be obtained, and the crushed and homogenized graphite material is 60 to 80°C. It is desirable to dry at a temperature of 12 to 36 hours.

At this time, the particle size of the graphite material is appropriately selected in consideration of the specific characteristics or process conditions and working environment of the heat dissipation structure, which is the final product, and it is preferable to perform it repeatedly until the particle size of the graphite material becomes 1-50 μm. . When the particle size of the graphite material is less than 1 µm, it is difficult to crush, and the change in the shape-prevention performance is small due to the reduction in size, and when it exceeds 50 µm, the ratio of the resin to the surface layer of the molded article is increased, so that thermal conductivity and heat dissipation performance are improved. Since it acts as a deteriorating factor, it is not appropriate.

Then, 2 to 20% by weight of the carbon material dispersion and 80 to 98% by weight of the graphite material are mixed to form a carbon-based mixed material, and a polymer resin is added to the carbon-based mixed material to form a carbon-based material. In other words, by weight, 40 to 60% by weight of the carbon-based mixed material and 40 to 60% by weight of a polymer resin is mixed and stirred to form a carbon-based material. When stirring, it is preferable to stir at a stirring speed of 100 to 120 rpm for 60 to 150 minutes.

The polymer resin serves as a binder for connecting the carbon-based mixed material, and is made of polyamide resin or polyphenylene sulfide. As the polymer resin is added, it has easy processability and economical efficiency for molding into a heat dissipation structure, and is mixed with a carbon-based mixed material composed of a graphite material and a carbon material dispersion having excellent thermal conductivity to form a molded structure having heat dissipation properties. To form.

At this time, when the content of the carbon-based mixed material exceeds 60% by weight, not only may the molding of the heat dissipation structure be difficult, but also the mechanical properties of the molded structure may be deteriorated, and when it is less than 40% by weight, heat dissipation performance Insignificant, unsuitable for use as a material for heat dissipation structures.

In addition, a trace amount of a silicon-containing compound may be added to improve the surface coating of the carbon-based mixed material and the corrosion resistance of the polymer resin. In this case, the silicon-containing compound is made of at least one selected from the group consisting of potassium silicate, sodium silicate, silicon oxide, silicon nitride and silicon carbide.

On the other hand, since the carbon-based material cannot be used as it is, it can be formed into pellets and stored. In this case, it is preferable to further add 1 to 5% by weight of a decomposition inhibitor and an antioxidant for preventing decomposition of the polymer by ultraviolet rays.

The decomposition inhibitor is from a group consisting of hydroxybenzophenone, hydroxyphenyl benzotriazole, arylester, oxanilides, and formamidine. It may be made of one or more selected. In addition, the antioxidant may be made of at least one selected from the group consisting of phenol-based antioxidants, phosphorus-based antioxidants, sulfur-based antioxidants, and amine-based antioxidants.

In addition, the insulating bonding layer 200 attaches the electric conductive layer 300 to the heat dissipation structure 100 and insulates the electric current flowing through the electrical conductive layer 300 so as not to be transmitted to the heat dissipation structure 100. As, it is located on the surface portion 110 of the heat dissipation structure 100. In addition, the electrical conductive layer 300 is for forming a circuit on which a plurality of electronic components are mounted, and is preferably made of copper foil. The electrical conductive layer 300 forms a circuit connecting a plurality of electronic components through a process such as etching.

The heat dissipation structure-integrated printed circuit board of the present invention configured as described above does not use a separate substrate, utilizes a heat dissipation structure formed of a carbon-based material as a substrate, and forms a circuit using an electrical conductive layer.

Accordingly, since a separate plastic or metal substrate is not used, the overall weight is reduced, and heat generated from a plurality of electronic components mounted on the electrically conductive layer is discharged through the heat dissipation structure, thereby improving the heat dissipation effect. And, as the heat dissipation structure is formed of a carbon-based material having excellent conductivity and emissivity, the heat dissipation effect is greatly improved.

On the other hand, after manufacturing a plate using a carbon-based material in order to verify the heat dissipation effect of the heat dissipation structure constituting the integrated circuit board of the heat dissipation structure according to the present invention, the thermal conductivity in the horizontal direction and the thermal conductivity and emissivity in the vertical direction, respectively As a result of comparison, it was shown in Table 1.

<Comparative Example>

After the plate was made of a carbon-based material composed of 50% by weight of plate-like graphite and 50% by weight of polyamide resin, the heat conductivity in the horizontal direction and the heat conductivity and emissivity in the vertical direction were measured and set as standards.

<Example 1>

After the plate was made of a carbon-based material composed of 35% by weight of plate graphite, 20% by weight of spherical graphite, 3% by weight of carbon nanotubes, and 42% by weight of polyamide resin, thermal conductivity in the horizontal direction and thermal conductivity in the vertical direction Degrees and emissivity were measured respectively.

<Example 2>

After the plate was made of a carbon-based material composed of 25% by weight of graphite graphite, 30% by weight of spherical graphite, 30% by weight of spherical graphite, 5% by weight of carbon nanotubes, and 40% by weight of polyamide resin, thermal conductivity in the horizontal direction and thermal conductivity in the vertical direction Degrees and emissivity were measured respectively.

<Example 3>

After the plate was made of a carbon-based material composed of 30% by weight of plate graphite, 20% by weight of spherical graphite, 8% by weight of carbon nanotubes, and 42% by weight of polyamide resin, heat conduction in the horizontal direction and heat conduction in the vertical direction Degrees and emissivity were measured respectively.

Referring to Table 1 above, as the materials of the carbon-based material for forming the heat dissipation structure further include spheroidal graphite and carbon nanotubes, the thermal conductivity in the horizontal direction and the vertical direction increased, respectively, and it was confirmed that the emissivity also increased. Became. In particular, it was confirmed that the thermal conductivity and emissivity increased as the content of carbon nanotubes increased compared to that of spheroidal graphite.

And, the method of manufacturing the heat-dissipating structure integrated printed circuit board of the present invention, as shown in Figures 3 and 4, based on the total weight of 40 to 60% by weight of the carbon-based mixed material and 40 to 60% by weight of polymer resin A heat radiation structure forming step (S10) of injection or extrusion of a pellet made of a carbon-based material to form a heat radiation structure 100; After the insulating bonding sheet 200 and the electrically conductive layer 300 are sequentially stacked on the surface portion 110 of the heat dissipation structure 100, the pressure of 25 to 35 kgf/cm 2 and the temperature of 150 to 230° C. are 2~. A bonding step (S20) of attaching the electric conductive layer 300 to the heat dissipation structure 100 by cooling for 1 hour after hot pressing for 3 hours; A circuit printing step (S30) in which the surface of the electrical conductive layer 300 is front-treated and the circuit is printed and dried for 30-40 minutes at a temperature condition of 160-230°C; An etching step (S40) of etching the electric conductive layer 300 so that all parts except the circuit are removed by photosensitive treatment using a photoresist and a mask; A PSR printing step (S50) of printing an insulating reflective layer (PSR) on the electrically conductive layer 300 having only the circuit remaining and drying it for 30-40 minutes at a temperature condition of 170-180°C; Marking printing step (S60) for performing the marking printing after the frontal treatment and drying for 30-40 minutes at a temperature condition of 150-170°C; BBT (Bare Board Test) step (S70) of checking whether there are any abnormalities in the circuit and the board before mounting the electronic component; A surface treatment step (S80) of coating an anti-corrosive film on the circuit surface, such as OSP (Organic Solderability Preservative) treatment; A router step (S90) of cutting a PCB using a router and processing an outer shape; It includes; inspection step (S100) of inspecting and inspecting the product quality and shipment step (S100) of shipping the finished product.

Here, the frontal treatment of the circuit printing step (S30) is to remove foreign substances on the surface of the electrically conductive layer 300, and the frontal treatment in the marking and printing step (S60) is heat dissipation using a sandblasting process or a sandbrush. It is to increase the surface area of the structure.

In addition, since the BBT step (S70), the surface treatment step (S80), the router step (S90), the inspection step (S100), and the shipping step (S110) are the same as the existing PCB manufacturing process, a description thereof will be omitted.

On the other hand, the bonding step (S20), as shown in Figure 5, the flat surface portion 110 and a pair of heat dissipation structure 100 having a concave-convex back portion 120, the rear surface portion 120 ) Are arranged in the form of interlocking with each other, and then the insulating bonding sheet 200, the electric conductive layer 300, and the protective film 400 are sequentially stacked from the flat portion 110 of each heat dissipation structure 100. After placing the protective plate 500 of aluminum or stainless steel on the upper and lower sides to stack and lay up 2 to 4 layers in a way to protect and separate them, lay up (S21), and then use a vacuum heat press of 5 to 10 kgf/㎠. Initial pressure is applied until the pressure reaches 150°C for 5 to 15 minutes, and secondly, temperature and pressure are applied at a vacuum hot press for 110 to 150 minutes at a temperature of 150 to 230°C under a pressure of 25 to 35 kgf/cm 2 After performing the lamination bonding (S22), it may be made in a manner of cooling for 60 to 90 minutes while applying a pressure of 5 to 10 kgf/cm 2 at a temperature of 20 to 40°C.

In addition, through the bonding step (S20), the heat dissipation structure to which the electrical conductive layer is attached may be shipped in the form of a semi-finished product without forming a circuit. That is, the semi-finished products laminated in the lay-up state are disassembled (S25), respectively, and then subjected to shipment inspection (S26) to be packaged and shipped as semi-finished products (S27). Accordingly, it is possible to purchase a printed circuit board in a semi-finished state, print the desired circuit, and perform the remaining processes such as etching, insulating reflective layer printing, and marking printing to produce a desired printed circuit board.

As described above, although described and illustrated in connection with some embodiments for illustrating the technical idea of the present invention, the present invention is not limited to the configuration and operation as described above, and the scope of the technical idea described in the description of the invention It will be understood by those skilled in the art that many changes and modifications to the present invention are possible without departing. Accordingly, all such suitable modifications and modifications and equivalents should be considered as falling within the scope of the present invention.

100...heat-resistant structure
110...surface
120...
200...insulation bonding sheet
300...electric conductive layer
400...protective film
500...protection

Claims (5)

A heat dissipation structure 100 formed of a carbon-based material comprising 40 to 60% by weight of a carbon-based mixed material and 40 to 60% by weight of a polymer resin based on the total weight;
An electric conductive layer 300 formed of a conductor plate so that a circuit can be formed;
Including; an insulating bonding layer 200 formed on the upper surface of the heat dissipation structure 100 so that the electrical conductive layer 300 is attached to the heat dissipation structure 100;
The carbon-based mixed material includes a carbon material dispersion and a graphite material,
The carbon material dispersion comprises at least one carbon material and a solvent selected from the group consisting of carbon nanotubes, graphene and carbon black,
The graphite material is a heat-radiating structure-integrated printed circuit board, characterized in that it consists of two or more selected from the group consisting of impression graphite, expanded graphite, plate-like graphite, and spherical graphite.
According to claim 1,
The carbon-based material for forming the heat dissipation structure 100 further includes 1 to 5% by weight of a decomposition inhibitor and an antioxidant for preventing decomposition of the polymer by ultraviolet rays,
The decomposition inhibitor is from a group consisting of hydroxybenzophenone, hydroxyphenyl benzotriazole, arylester, oxanilides, and formamidine. It consists of one or more selected,
The antioxidant is a phenol-based antioxidant, phosphorus-based antioxidant, sulfur-based antioxidant, amine-based antioxidant, heat-resistant structure integrated printed circuit board, characterized in that at least one member selected from the group consisting of.
The method according to claim 1 or 2,
The heat dissipation structure 100 is characterized in that it comprises a flat surface portion 110 on which the insulating bonding layer 200 is seated and a rear surface portion 120 formed in an uneven shape so as to increase the heat dissipation area. Structure-integrated printed circuit board.
Forming a heat dissipation structure to form a heat dissipation structure 100 by injection or extrusion of pellets made of a carbon-based material containing 40 to 60 wt% carbon-based mixed material and 40 to 60 wt% polymer resin based on the total weight Step S10;
After the insulating bonding sheet 200 and the electrically conductive layer 300 are sequentially stacked on the surface portion 110 of the heat dissipation structure 100, the pressure of 25 to 35 kgf/cm 2 and the temperature of 150 to 230° C. are 2~. A bonding step (S20) of attaching the electric conductive layer 300 to the heat dissipation structure 100 by cooling for 1 hour after hot pressing for 3 hours;
A circuit printing step (S30) in which the surface of the electrical conductive layer 300 is front-treated to print the circuit and dry it for 30 to 40 minutes at a temperature condition of 160 to 230°C;
An etching step (S40) of etching the electrical conductive layer 300 so that all parts except the circuit are removed by photosensitive treatment using a photoresist and a mask;
A PSR printing step (S50) of printing an insulating reflective layer (PSR) on the electrically conductive layer 300 having only the circuit remaining and drying it for 30-40 minutes at a temperature condition of 170-180°C;
A method of manufacturing a heat-radiating structure-integrated printed circuit board, comprising: a marking printing step (S60) of performing a marking printing after the frontal treatment and drying it for 30-40 minutes at a temperature condition of 150-170°C.
According to claim 4,
In the bonding step (S20), a pair of heat dissipation structures having a planar surface portion and a concave-convex back portion are arranged in a form in which the concavo-convex portions of the back surface are engaged with each other, and then the insulating bonding sheet and the electricity from the flat portion of each heat dissipation structure are arranged. The conductive layer and the protective film are sequentially stacked, and aluminum or stainless steel protective plates are placed on the upper and lower portions to protect and separate them. Initial pressure is applied until the pressure reaches 150℃ for 5 to 15 minutes at a pressure of ㎏f/㎠, and secondly at a temperature of 150 to 230℃ at a pressure of 25 to 35㎏f/㎠ for 110 to 150 minutes in a vacuum hot press. After performing lamination bonding to which temperature and pressure are applied, a heat dissipation structure-integrated printed circuit board characterized in that it is cooled by 60 to 90 minutes while applying a pressure of 5 to 10 kgf/cm 2 at a temperature of 20 to 40°C. Manufacturing method.

Images