WO2014104559A1

WO2014104559A1 - Led heat-dissipation flexible module using carbon fiber substrate and method for manufacturing same

Info

Publication number: WO2014104559A1
Application number: PCT/KR2013/009815
Authority: WO
Inventors: 최은국; 추정훈
Original assignee: 하이쎌 주식회사
Priority date: 2012-12-28
Filing date: 2013-11-01
Publication date: 2014-07-03
Also published as: KR101399980B1

Abstract

The present invention relates to a high heat-dissipation printed circuit board and a method for manufacturing the same, the circuit board comprising: a heat-dissipation layer comprising carbon fiber fabrics; an insulation layer formed on the heat-dissipation layer; a wiring layer formed on the insulation layer and patterned by a printing method of a conductive paste composite; and a metal plating layer formed on the patterned wiring layer. Since the high heat-dissipation printed circuit board, according to the present invention, can have relatively improved heat-dissipation, light-weightness and flexibility characteristics, the high heat-dissipation printed circuit board can be applied to an LED heat-dissipation flexible module.

Description

Thermal radiation flexible module for LED using carbon fiber substrate and manufacturing method thereof

The present invention relates to a heat dissipation flexible module for a LED using a carbon fiber substrate and a method for manufacturing the same, and more particularly, a high heat dissipation printed circuit using a carbon fiber substrate as a heat dissipation plate, and including a printed circuit of a conductive paste. It relates to a substrate and a method of manufacturing the same.

The high heat dissipation printed circuit board according to the present invention may have more improved heat dissipation characteristics, light weight and ductility, and thus may be applied as a heat dissipation flexible module for LEDs.

In general, a printed circuit board (PCB) is a thin plate on which electrical components such as integrated circuits, resistors, or switches are soldered. Circuits used in most computers and various display devices are installed on the printed circuit board.

Common methods for manufacturing the printed circuit board (PCB) include an etching method and a method using a conductive paste. In the etching method, a laminated plate is manufactured by casting, laminating, and sputtering a copper foil, which is a conductor, on an insulating material of a polymer resin, and applying a photolithography method to dissolving and removing unnecessary parts of the copper foil with chemicals, thereby requiring only a conductive pattern. By leaving it is a method of manufacturing a printed circuit board. Such an etching method is widely used because of excellent mass productivity, but the etching method requires a lot of facility facilities because it consists of several processes, and there is a problem in that the production cost increases due to the number of processes. In addition, this etching method uses an etching solution that is harmful to the human body. Therefore, these etching solutions have to be collected and processed, which is not environmentally friendly. Moreover, the cost of the photoresist used in the etching process is high, and the copper layer is used. There are many problems in the loss of material by etching and removing.

In order to solve the problem of the etching method, a technique of manufacturing an inexpensive printed circuit board (PCB) by replacing copper clad, which is a circuit pattern material, with conductive ink / paste, is an etching method. Is replacing.

The conductive ink is generally a material in which metal particles of several tens to several tens of nanometers in diameter are dispersed in a solvent. When the conductive ink is printed on a substrate and heated at a predetermined temperature, organic additives such as a dispersant are volatilized, and the metal particles are dispersed. The voids between them shrink and sinter to form conductors that are electrically and mechanically connected to each other. In addition, the conductive paste is generally a material in which metal particles of several hundreds to thousands of nanometers in diameter are dispersed in an adhesive resin, and the conductive paste is printed on a substrate, and the resin is cured when heat is applied at a predetermined temperature. And electrical and mechanical contacts between the metal particles are fixed to form conductors connected to each other.

One of the most problematic areas when configuring electronic circuits using electronic components on such printed circuit boards is a countermeasure against heat of components in which heat is generated. That is, when a predetermined voltage is applied to the electronic component, a current flows, which inevitably generates heat due to resistance loss. At this time, there are some electronic parts that do not interfere with operation due to natural air cooling due to the low heat generation.However, in the case of heat generating parts in which the temperature of electronic parts continuously increases due to a lot of heat generated, there is a limit to only natural air cooling. And breakage is sometimes a problem, such heat generation causes a problem in the reliability of the entire electronics.

For example, LEDs, which are expanding their use not only for LCD TV backlights but also for lighting, emit light and heat, unlike ordinary lamps, while driving light, which accounts for about 20-30% and 70-80% of heat. Done. In particular, when heat generated during operation is quickly radiated, the light efficiency is also improved. In order to effectively transmit such heat, a metal circuit board is generally used.

In addition, in order to heat and cool the heat generated by the circuit in general, a heat sink may be provided under the substrate, and a metal such as aluminum or magnesium is mainly used as a conventional substrate material. However, the metal has the disadvantage that the weight of the substrate can not be reduced, and has a limitation that easy processing is difficult.

In order to solve these problems, various structures for dissipating and cooling the generated heat have been proposed. For example, Japanese Patent Application Laid-Open No. 10-2012-0082947 (2012.07.24) discloses an aluminum substrate layer and a technology related to a heat dissipating laminate in which an adhesive layer, a resin layer, an adhesive layer, and a copper layer or an aluminum layer are laminated on the aluminum substrate layer. Patent Application Publication No. 10-2012-0072801 (2012.07.04.) Discloses an electrodeposition coating in which a first insulating layer by anodizing is formed, electrodeposited, and a second insulating layer is formed to form a circuit. The high heat dissipation substrate used and its manufacturing method are described.

However, in spite of various efforts to increase heat dissipation efficiency by changing the material or material of the printed circuit board including the conventional technology, a new concept that has excellent heat dissipation efficiency, high strength, and can meet the slimming of electronic products. There is a continuing need for research and development on heat dissipation substrates.

Accordingly, an object of the present invention is to provide a novel high heat dissipation printed circuit board and a manufacturing method thereof having excellent heat dissipation efficiency and high strength.

Another object of the present invention is to provide a printed circuit board that includes a light-weight heat-dissipating substrate and improves conductivity while reducing the thickness of a wiring layer when forming a pattern by a direct printing method of a conductive paste.

In another aspect, the present invention is to provide a heat-dissipating flexible module for LED that can reduce heat generation and slim the product by using the high heat-dissipation printed circuit board and excellent electrical conductivity and uniformity and thickness of the wiring layer. For other purposes.

The present invention is a heat radiation layer comprising a carbon fiber fabric; An insulation layer formed on the heat dissipation layer; A wiring layer formed on the insulating layer and patterned by a printing method of a conductive paste composition; And a metal plating layer formed on the patterned wiring layer.

Further, in the present invention, the wiring shape of the patterned wiring layer is formed between the insulating layer and the wiring layer patterned by the printing method of the conductive paste composition so as to partially support the patterned wiring layer by being formed on the insulating layer. Accordingly, a second insulating layer may be additionally formed.

In addition, the present invention comprises a carbon fiber fabric by heating the binder having fluidity at high temperature to convert it into a liquid phase and filling it in the empty space made by the weft and warp of at least one or more carbon fiber fabrics to be used as a heat dissipation layer, Forming a heat dissipation layer; The base substrate is attached by attaching one insulating layer selected from polybutylene terephthalate, polyethylene terephthalate, polysulfone, polyether, polyetherimide, heat resistant epoxy, polyarylate and polyimide to the heat dissipating layer. Forming; Forming a patterned wiring layer by printing a conductive paste composition comprising any one or a mixture thereof selected from conductive Ag paste, conductive Cu paste, conductive polymer, and gravure paste on the insulating layer of the base substrate in a predetermined pattern. step; And forming a metal plating layer on the patterned wiring layer by plating. The method of manufacturing the printed circuit board may include:

In addition, the present invention is a conductive Ag paste on any one insulating layer selected from polybutylene terephthalate, polyethylene terephthalate, polysulfone, polyether, polyetherimide, heat-resistant epoxy, polyarylate and polyimide, Forming a patterned wiring layer by printing a conductive paste composition including any one or a mixture thereof selected from a conductive Cu paste, a conductive polymer, and a gravure paste in a predetermined pattern; Forming a metal plating layer on the patterned wiring layer by plating; Forming a heat dissipating layer comprising a carbon fiber fabric by heating the binder having fluidity at a high temperature to convert it into a liquid phase and filling it into an empty space formed by the weft and warp of at least one carbon fiber fabric to be used as a heat dissipating layer. ; And attaching an insulating layer including the wiring layer and the metal plating layer by the conductive paste to the heat dissipating layer.

In another aspect, the present invention can provide a heat dissipation flexible module for an LED including the high heat dissipation printed circuit board.

The high heat dissipation printed circuit board of the present invention is excellent in heat dissipation efficiency, has a high strength, and has the advantage of meeting the slimming of electronic products.

In addition, the present invention includes a heat-dissipating substrate which is light in weight, and can provide a printed circuit board having improved conductivity while thinning the thickness of the wiring layer by metal plating after forming the wiring by the direct printing method of the conductive paste.

The high heat dissipation printed circuit board of the present invention can reduce heat generation by reducing the uniformity and thickness of the wiring layer and the excellent electrical conductivity when used as a heat dissipation module for LEDs, and also can reduce the product weight with light weight and ductility. There is an advantage.

1 is a cross-sectional view of a high heat radiation printed circuit board according to an embodiment of the present invention.

Figure 2 is a view showing a carbon fiber fabric which is a material of the heat sink used in the present invention.

3 is a cross-sectional view of a high heat radiation printed circuit board in which a binder is filled in a void space of a carbon fiber fabric when the heat dissipation layer is manufactured according to an embodiment of the present invention.

Figure 4 is a cross-sectional view of a high heat radiation printed circuit board according to another embodiment of the present invention.

5 is a diagram illustrating a manufacturing method of a high heat radiation printed circuit board according to an exemplary embodiment of the present invention.

6 is a diagram illustrating a manufacturing method of a high heat radiation printed circuit board according to another embodiment of the present invention.

Hereinafter, a printed circuit board and a method of manufacturing the same will be described in detail with reference to the accompanying drawings.

1 is a view showing a cross-sectional view of a high heat radiation printed circuit board according to an embodiment of the present invention. As can be seen in Figure 1, the high heat radiation printed circuit board according to the present invention is a heat radiation layer 12 including a carbon fiber fabric, an insulating layer 11 formed on the heat radiation layer, formed on the insulating layer and conductive Provided is a high heat radiation printed circuit board comprising a wiring layer 10 patterned by a printing method of a paste composition and a metal plating layer 13 formed on the patterned wiring layer.

In the present invention, the heat dissipation layer of the high heat radiation printed circuit board includes a carbon fiber fabric.

In general, carbon materials have high strength and thermal conductivity, and have a low density compared to metals, so that a lightweight substrate can be produced. A coating layer for improving heat dissipation, and a heat dissipating insulating layer used in combination with an adhesive resin having improved heat dissipation characteristics. It is used in powder form or sheet form.

However, when used as a substrate material in the form of a sheet as described above, it is susceptible to impact, and there is a problem of cracking when bent or bent. Therefore, the present invention is to use the carbon fiber in the form of a fabric to improve the durability to use as a heat radiation layer.

In general, carbon fiber is carbonized as polyacrylonitrile yarn, viscose yarn, pitch-based yarn, etc. are stretched in the longitudinal direction, and the carbon fiber has advantages of high strength and thermal conductivity such as electrical and mechanical properties. It is researched in various applications such as materials and precision machine parts.

Figure 2 shows a figure showing a carbon fiber fabric as a material of the heat dissipation layer used in the present invention. The carbon fiber fabric is a woven fabric of carbon fibers by warp and weft yarns, and as shown in FIG. 2, the structure is not a flat structure but has a half space between the warp yarns and the weft yarns. In addition, due to the empty space, even in direct contact with the insulating layer, the portion directly contacting the insulating layer may have a problem in adhesive strength and heat dissipation effect.

therefore. In order to fill the empty space, in the present invention, a binder may be used to fill the half space between the warp yarn and the weft yarn. In this case, the binder used should have fluidity at a high temperature, and a high thermal conductivity should be used.

Generally, the binder may be used regardless of its kind as long as it has excellent chemical resistance, but preferably, epoxy or silicone may be used. Here, when considering the metal plating process after forming the conductive paste wiring layer on the insulator, since the plating process is performed under strong basic or strong acid conditions, it is preferable not to use an acrylic binder having basicity and reactivity.

Figure 3 is a view showing a cross-sectional view of a high heat radiation printed circuit board in which the bonding agent is filled in the empty space of the carbon fiber fabric in the manufacture of the heat dissipation layer. In this regard, the binder shown in the voids of the carbon fiber fabric flows sufficiently between the voids of the carbon fiber fabric to fill the voids, and there is no air or void space between the bonding surface with the insulating layer. . The bonding agent must be melted in a viscous liquid state by heating to be introduced into the carbon fabric to form a bonding surface with the insulating layer without the void space, thereby having good thermal conductivity.

In the present invention, the binder component may include a metal powder, a polymer material powder, a ceramic powder, or a mixed powder thereof having excellent thermal conductivity selected from among aluminum, copper, and nickel.

In this case, the average particle diameter of the metal powder which may be additionally included in the binder component may range from 0.1 um to 10 um.

In addition, the heat dissipation layer in the present invention may be a plurality of carbon fiber fabric is laminated. In the case where the carbon fiber fabric is laminated in a plurality of layers, the binder component may be obtained by laminating each carbon fiber fabric with the binder component already filled or by filling the binder at once after laminating each carbon fiber fabric. A heat dissipation layer can be formed.

The thickness of the heat dissipation layer of the carbon fiber fabric containing the binder may be 10um to 150um, preferably 40um to 80um.

In addition, in the present invention, the insulating layer and the heat dissipating layer may be more easily attached to the heat dissipating layer made of the carbon fiber fabric including the bonding agent by using an additional adhesive or an additional adhesive of epoxy or silicon type.

In the present invention, the insulating layer may be used a variety of substrates such as polymer materials, ceramics, glass, silicon, more preferably polybutylene terephthalate, polyethylene terephthalate, polysulfone, polyether, polyetherimide, It may be any one selected from heat resistant epoxy, polyarylate and polyimide.

In addition, the thickness of the insulating layer should be thin in order to improve heat dissipation characteristics, but when the insulating layer becomes thinner, withstand voltage characteristics (the highest voltage that can withstand without destroying the insulation mechanism, MPCB generally used Must withstand 5,000 V / min.) And fall off to find the balance of both characteristics and adjust accordingly.

In general, the thickness of the insulating layer that can be used may be 10um to 100um, preferably 12um to 25um.

In addition, the conductive paste wiring layer formed on the insulating layer may be formed by printing the conductive paste composition by a printing method.

In addition, the conductive paste used in the present invention includes particles of electrically conductive materials, which are conductive metals, nonmetals or powders of oxides, carbides, borides, nitrides, carbonitrides, and carbon such as carbon black and graphite. It includes a system powder. The conductive paste particles may be formed of, for example, gold, aluminum, copper, indium, antimony, magnesium, chromium, tin, nickel, silver, iron, titanium, alloys thereof, and oxides, carbides, borides, nitrides, and carbonitrides thereof. It may include particles. The shape of the particles is not particularly limited, and for example, plate-shaped, fiber-type and nano-sized nanoparticle nanotubes may be used. These conductive particles may be used alone or in combination.

In addition, unlike the conductive ink used in inkjet printing, the conductive paste may further include a binder to improve adhesion to the substrate, and generally, an epoxy resin, a phenol resin (phenol + formaldehyde), and a polyurethane resin. Organic binders such as polyamide resin, acrylic resin, urea / melamine resin and silicone resin can be used. The content of the binder may generally range from 10 to 50 wt% with respect to the content of the total paste composition, preferably from 15 to 40 wt%, but is not limited thereto. As described above, the binder serves to reduce the electrical conductivity of the wiring layer including the conductive paste.

In addition, the viscosity of the conductive paste composition used in the present invention may be used in the range of 23 ℃, 50 rpm HAKKE RHeoscope measurement standard 10,000 cps ~ 100,000 cps, but is not limited thereto.

Additionally, other additives may include Ag powder (pigment), natural and synthetic resins (binder), solvents, dispersants, coupling agents, viscosity modifiers and the like.

The conductive paste composition in the present invention may be preferably any one selected from conductive Ag paste, conductive Cu paste, conductive polymer, paste for gravure, or a mixture thereof.

The gravure paste is a kind of conductive silver (Ag) paste and has a particle size of 0.1 to 3 μm. For example, the gravure paste may be composed of 75% Ag powder, 10% resin, and 13% solvent 13% additive.

In addition, the particle size of the conductive paste composition may be in the range of 10 nm to 10 um, and a conductive paste having a 30 to 1,000 nm nanoparticle size or a conductive paste having a micro particle size of 1 to 7 um is preferable.

In general, the larger the particles of the paste, the lower the electrical conductivity of the wiring layer is formed, the greater the effect of the conductivity improvement by the formation of the wiring layer through the plating layer of the present invention when the paste particles have a micro size range can be greater. have.

In the present invention, the conductive paste may form a wiring layer patterned in a pattern of a shape desired by a user by a direct printing method on a substrate. The direct printing method may include a printing method such as screen printing, flexographic printing, rotary printing, gravure printing, offset printing, or dispenser on a substrate. In each printing method, a conventionally well-known means can be used. Among the printing methods, screen printing, gravure printing or offset printing is preferable.

On the other hand, in general, the circuit wiring implemented by printing a conductive paste on the substrate has a high resistance, so the conductivity is not good, so it is difficult to use it as a circuit wiring, and there is a problem in that adhesion is not performed when using general solder paste. . In order to solve this problem, a metal plating layer may be formed on the conductive paste wiring.

In the present invention, the metal plating layer formed on the conductive paste wiring layer may be formed by electrolytic plating or electroless plating.

The thickness of the metal plating layer formed on the patterned wiring layer is 1 um to 10 um, preferably 2 to 5 um.

Preferably, the metal plating layer in the present invention may be formed by electroless plating. In this case, the uniformity of the wiring can be better than that of the metal plating layer formed by electroplating. This will be described in more detail below.

In general, in the case of electroplating, plating is not properly performed due to the large resistance of the conductive paste during electroplating, or the plating thickness is greatly varied due to the variation in resistance. For example, the start point of the wiring during the electroplating is located close to the electrode, and the reduction reaction of the metal occurs well so that the plating layer can be smoothly formed on the conductive paste layer, but as the wiring layer including the paste layer moves away from the starting point, The electrical conductivity of the paste is not as good as that of metal, and the efficiency of the reduction of metal ions is reduced due to the presence of a resistance along the length of the conductive paste. Therefore, as the wiring moves away from the starting point of the electrode, the thickness of the plating layer formed may become thin, and even the wiring may be formed discontinuously.

In order to solve the above problems, if the thickness of the plating layer is made thick, the thickness of the finally manufactured circuit board may be thickened, and it may also provide a cause of defects during printing due to the high thickness.

In addition, in the case where the plating amount is increased during electroplating in order to increase the thickness of the plating layer, only the upper end portion of the wiring layer may be plated instead of the upper portion of the wiring layer, thereby forming a narrow width (pitch width) between the wiring lines. There is a disadvantage that can not.

However, in the case of electroless plating on the patterned wiring layer of the conductive paste, there is an advantage in that the thickness of the electroplating layer according to the length of the wiring, which may be caused by the electroplating, may be eliminated.

In addition, in the case of forming the plating layer by the electroless plating, in the case of electroplating, the disadvantage of thickening the circuit board, which is a problem caused by thickening the plating layer to improve the conductivity of the wiring, can be improved. It is possible to form a narrower width (pitch width) between the wiring lines than forming the metal plating layer by electroplating. Because in order to overcome the disadvantage that the thickness of the electroplating layer according to the length of the wiring during the electroplating, it is necessary to increase the thickness of the plating layer as described above, for this purpose, the plating amount should be increased during the electroplating, in this case, the wiring layer Only the upper end portion of is not plated, and the side portion of the wiring layer may be plated. Therefore, in the case of forming the metal plating layer on the conductive paste layer by electroplating, in order to form a highly conductive wiring, the plating layer is formed on the side of the wiring layer by making the thickness of the plating layer thick, so that the width (pitch width) between the wiring lines is narrowly formed. However, when the metal plating layer is formed on the conductive paste layer by electroless plating as in the present invention, the thickness of the electroplating layer according to the length of the wiring is not solved. The width (pitch width) between the wiring lines can be formed narrower than that in the case of forming the plating layer by electroplating.

In the present invention, the metal plating layer is formed by electroless plating, and optionally, a metal plating layer by electroplating may be additionally formed on the plating layer formed by the electroless plating.

In addition, the metal used in the electroless metal plating in the present invention may be any one selected from Cu, Sn, Ag, Au, Ni or alloys thereof, but is not limited thereto. Preferably Cu, Ag or Ni can be used.

In this case, the wiring layer formed by the electroless plating can form a layer thinner than the wiring layer by the conventional electroplating, and thus has the advantage of improving the electrical conductivity of the wiring.

Meanwhile, in the present invention, a seed metal layer for forming the electroless metal plating layer may be further formed between the patterned conductive paste wiring layer and the electroless metal plating layer.

The seed metal layer may improve the reaction rate and selectivity of the electroless plating by allowing the seed metal to be adsorbed on the paste layer and thereby reducing the metal ions forming the electroless chemical plating layer.

The metal for forming the seed metal layer may be selected from Au, Ag, Pt, Cu, Ni, Fe, Pd, Co, or an alloy thereof, and seed metal components such as halides, sulfates, acetates, complex salts of seed metal components, and the like. Any component can be used as long as it is a transition metal salt.

In addition, the present invention in forming the seed metal layer, the seed metal layer may contain other additional transition metal components other than the seed metal component.

Additional transition metal components other than the seed metal may be contained using transition metal salts such as metal halides, metal sulfates, and metal acetates, and for this purpose, the same metal components as those of the electroless plating layer formed on the conductive paste layer may be used. It is preferable to use a salt of.

In the case of using the seed metal layer, the electroless plating layer can be formed more quickly, and the electroless plating layer serves to help the electroless plating layer be formed only on the wiring layer on the conductive paste.

The wiring layer formed by the electroless plating of the present invention can form a layer thinner than the wiring layer by the conventional electroplating, there is an advantage that can improve the electrical conductivity of the wiring.

On the other hand, in the present invention, when the electroless metal plating layer further comprises an electrolytic metal plating layer, the electrolytic metal plating layer further formed is any one selected from Ni, Cu, Sn, Au, Ag or alloys thereof, or Ni-P alloy, which is formed on the electroless plating layer, may be electroplated onto a metal wiring layer having a higher electrical conductivity than the conductive paste, thereby conducting a wiring layer (a layer including a conductive paste layer, an electroless plating layer, and an electroplating layer). Can be further improved.

In addition, the present invention is a wiring shape of the patterned wiring layer so as to support the patterned wiring layer by being partially formed on the insulating layer between the insulating layer and the wiring layer patterned by the printing method of the conductive paste composition. Accordingly, a second insulating layer may be additionally provided.

4 is a cross-sectional view of a high heat dissipation printed circuit board including the second insulating layer of the present invention. Looking at this, it can be seen that the second insulating layer 15 is provided between the conductive paste wiring layer 10 and the insulating layer 11.

In this case, the second insulating layer 15 may be formed by a printing method, and more specifically, the liquid thermal conductive insulating material may be formed as a second insulating layer by a printing method.

As described above, the second insulating layer 15 may be any one selected from polybutylene terephthalate, polyethylene terephthalate, polysulfone, polyether, polyetherimide, heat resistant epoxy, polyarylate and polyimide. One polymer resin may be selected, and the second insulating layer may have a thickness in the range of 5 um to 50 um, preferably 10 um to 20 um, and the width of the insulating layer may be defined by the patterned wiring layer. It may be 1.5 to 10 times the wiring width.

When the second insulating layer is provided, the withstand voltage characteristic may be increased in the vicinity of the circuit wiring realized by the conductive paste, and the heat dissipation effect to the external space may be increased in the part away from the circuit wiring.

In addition, in the present invention, a heat dissipation coating layer may be additionally formed on the top and / or bottom of the finally obtained printed circuit board. In this case, the heat dissipation coating layer further enables an improved heat dissipation effect of 3 to 5% than the heat dissipation coating layer is not formed by widening the surface area.

The printed circuit board manufactured by the present invention may have heat reduction and improved heat dissipation characteristics, light weight, and ductility due to improved electrical conductivity, and thus may be applied as a heat dissipation flexible module for LEDs. More specifically, the wiring layer (the layer consisting of the conductive paste layer and the plating layer) is used as a current supply line to form a contact point so that the LED can be positioned on the wiring line formed by the wiring layer, and to solve the heat generated by the LED. By using a heat dissipation layer containing a heat dissipation material, by selectively providing an LED support to support the LED, it is applicable to the heat dissipation flexible module for LEDs.

In addition, the present invention can provide a method for manufacturing the high heat radiation printed circuit board, which will be described with reference to FIGS. 5 and 6.

5 is a diagram illustrating a method of manufacturing a high heat radiation printed circuit board according to a method of forming a base substrate by attaching the heat dissipation layer to an insulating layer and then forming a wiring layer on the insulating layer.

More specifically, it comprises a carbon fiber fabric by heating a binder having fluidity at a high temperature to convert it into a liquid phase and filling it in the empty space formed by the weft and warp of at least one or more carbon fiber fabrics to be used as a heat dissipating layer. Forming a heat dissipation layer; The base substrate is attached by attaching one insulating layer selected from polybutylene terephthalate, polyethylene terephthalate, polysulfone, polyether, polyetherimide, heat resistant epoxy, polyarylate and polyimide to the heat dissipating layer. Forming; Forming a patterned wiring layer by printing a conductive paste composition comprising any one or a mixture thereof selected from conductive Ag paste, conductive Cu paste, conductive polymer, and gravure paste on the insulating layer of the base substrate in a predetermined pattern. step; And forming a metal plating layer on the patterned wiring layer by plating.

This will be described in detail according to each step process as follows.

First, as a first step, a carbon fiber fabric is included by filling a void formed by the weft and warp of at least one carbon fiber fabric to be used as a heat dissipating layer by heating the binder having fluidity at a high temperature. The step of forming the heat dissipation layer is achieved by impregnating a carbon fiber fabric with a heated epoxy- or silicone-based binder.

The binder content may be impregnated with 10 to 50% by weight of the total weight, the heating temperature of the binder may be adjusted according to the viscosity characteristics according to the type and temperature of the binder, vacuum or in a carbon fiber fabric It is preferable to make viscosity low enough so that the part which contains air does not generate | occur | produce. The impregnated carbon fiber fabric optionally has a sufficient fluidity by adopting a step of different heating temperature, such as the first heating process (100 to 150 ℃) and the second heating process (150 to 230 ℃), etc. Can be impregnated with carbon fabrics. In addition, an ultrasonic device or the like may be used to increase the impregnation efficiency of the binder.

After the excessively fed binder is removed, the carbon fiber fabric impregnated with the binder can be cooled to room temperature and used in subsequent processes.

In the present invention, the heat dissipating layer may be laminated with a plurality of carbon fiber fabrics, in which case each of the plurality of carbon fiber fabrics is laminated with each after the binder component is impregnated into each carbon fiber fabric as described above. Alternatively, the thermal radiation layer may be formed by impregnating and filling the binder at a time after laminating each carbon fiber fabric.

In addition, the manufacturing method of the present invention, as described above for the binder component, it is possible to form a heat dissipation layer comprising a metal powder having excellent thermal conductivity selected from aluminum, copper, nickel or mixed powder thereof.

As a second step for producing a high heat dissipation substrate of the present invention, a polybutylene terephthalate, polyethylene terephthalate, polysulfone, polyether, polyetherimide, heat resistant epoxy, polyarylate and poly Attaching any one insulating layer selected from the mid to form a base substrate may be performed by attaching an insulating layer to the heat dissipating layer and laminating it through a hot press process.

More specifically, the hot press process may be performed through a vacuum hot press process. This is to prevent partial generation of air or vacuum inside the heat dissipating layer including the bonding agent and the bonding interface with the insulating layer, and the hot press process is performed for 10 minutes at a pressure of 10 to 30T, preferably 15 to 25T. To 1 hour.

Also, in the present invention, the insulating layer and the heat dissipating layer may be more easily attached to the heat dissipating layer made of the carbon fiber fabric including the bonding agent by using an additional adhesive or an additional adhesive. The thickness of the pressure-sensitive adhesive layer or the adhesive layer by the additional pressure-sensitive adhesive or additional adhesive may be formed in 1 um ~ 20 um. In the present invention, an epoxy or silicone type may be used as the pressure-sensitive adhesive.

The third step is patterned by printing a conductive paste composition including any one or a mixture thereof selected from conductive Ag paste, conductive Cu paste, conductive polymer, and gravure paste on the insulating layer of the base substrate in a predetermined pattern. Forming a wiring layer.

This may form a patterned wiring layer through pad printing, silk screen printing, gravure printing, and the like, as described above, and the particle size of the conductive paste composition may be in the range of 10 nm to 10 um, such as salpin bars. Preferably, a conductive paste having a particle size of 30 to 1,000 nm or a conductive paste having a micro particle size of 1 to 7 um is preferable.

Thereafter, according to the process conditions it may be further provided with a drying step of the paste. In this case, the drying method is not limited to the type corresponding to the degree appropriately selected and applied by those skilled in the art according to the process conditions used, but from 80 to 200 degrees, preferably from 100 to 160 degrees 10 minutes to 3 Hot air drying can be used for hours.

In addition, the paste may undergo a curing step depending on the conditions of use.

As a final step, the forming of the metal plating layer by plating on the patterned wiring layer is a step of forming a plating layer by electroplating or electroless plating.

Preferably, the present invention may form a metal plating layer on the patterned wiring layer by electroless plating. In the case of the electroless plating, an electroless plating layer may be formed on the paste by using a transition metal salt, a reducing agent, a complex, or the like. Can be formed.

The electroless plating may be performed by reducing metal ions by a reducing agent by reducing and depositing a metal on a substrate or the like using a plating solution in which a compound containing a metal ion and a reducing agent are mixed.

As the main reaction, the metal ions can be reduced by the reaction scheme described below.

^{Metal ion + 2HCHO + 4OH - =} > Metal (0) + 2HCOO - + H 2 + 2H 2 O

At this time, non-limiting examples of the metal used for electroless plating may be Ag, Cu, Au, Cr, Al, W, Zn, Ni, Fe, Pt, Pb, Sn, Au, and the like. May be used alone or in combination of two or more thereof.

The plating solution used in the electroless plating may include a salt and a reducing agent of a metal to be plated, and non-limiting examples of the reducing agent may include formaldehyde, hydrazine or salts thereof, cobalt sulfate (II), formalin, Glucose, glyoxylic acid, hydroxyalkylsulfonic acid or salts thereof, hypophosphoric acid or salts thereof, boron hydride compounds, dialkylamine boranes, and the like, and various reducing agents may be used depending on the type of metal.

Further, the electroless plating solution may be prepared by forming a metal salt with a metal ion, a metal ion and a ligand to form a ligand and a complexing agent for preventing the metal from being reduced in the liquid phase and unstable solution. It may include a pH adjuster to maintain a suitable pH.

The thickness of the electroless metal plating layer is 1 um to 30 um, preferably 1 um to 10 um, the metal used for the electroless metal plating is Ag, Cu, Au, Cr, Al, W, Zn, It may be any one selected from Ni, Fe, Pt, Pb, Sn, Au or alloys thereof.

For example, when forming a copper (copper) plating layer, 1 to 30 using copper sulfate, formarin, sodium hydroxide, ethylene diamin tera acetyl acetate (EDTA) and an aqueous solution to which 2.2-bipyridyl is added as an accelerator An electroless plating layer can be formed with a thickness of μm.

The electroless copper plating step may use a barrel plating apparatus.

In one embodiment, the electroless plating of the present invention is composed of 85% D / I Water, 10-15% supplement, 25% -NaOH 2-5%, stabilizer 0.1-1%, 37% formalin 0.5-2% After air stirring for 10 to 15 minutes, the plating process can be performed for 25 to 30 minutes at a temperature of 40 to 500 ℃, pH 13 or more.

Meanwhile, the present invention provides a method for forming an electroless metal plating layer on top of the wiring layer, between forming the wiring layer of the conductive paste and forming a plating layer by electroless plating a transition metal on the patterned wiring layer. The method may further include forming a seed metal layer.

The seed metal layer may be selected from Au, Ag, Pt, Cu, Ni, Fe, Pd, Co, or an alloy thereof, and may further contain other transition metal components other than the seed metal component. A palladium salt may be used as the seed metal layer, and additional transition metal components may be contained using transition metal salts such as metal halides, metal sulfates, and metal acetates, and for this purpose, the electroless plating layer formed on the conductive paste layer may be used. The salt of the same metal component as a component can be used.

For example, to form the seed layer, palladium is 500 ppm, copper sulfate 0.1%, stabilizer 1% Using an aqueous solution, the silver paste as a conductive paste in the aqueous solution may be dipped out of the substrate having the patterned pattern on the surface of the protective layer for 3 to 5 minutes, and then the electroless chemical copper plating may be performed through a drying process.

In the present invention, if the resistance value of the electroless plating layer is low, the electrical conductivity is increased, and if a lower resistance is required, the resistance of the electroless copper plating may be increased by increasing the content of the metal to be plated.

In addition, the forming of the metal plating layer by electroplating on the patterned wiring layer may include forming the patterned wiring layer in an aqueous solution of copper plating, for example, copper sulfate (CuSO ₄ ), sulfuric acid (H ₂ SO ₄ ), and a polishing agent. The electroplating layer can be formed by immersing the formed substrate to form an electrolytic copper plating layer with a desired thickness and washing the surface with water. For example, electrolytic copper plating may be carried out in a 10 wt% aqueous solution of sulfuric acid, copper sulfate 90 g / L, copper stabilizer 2 ml / L, copper copper polish 5ml / L, and HCI 0.16 ml / L at a temperature of 40 ° C. to 60 ° C.

In addition, the present invention can perform an electroless silver plating process after the paste printing process and the electroless copper plating process. The process conditions in this case also follow the general silver plating process, except that the metal salt used is silver salt (AgNo ₃ ) rather than copper salt.

In one embodiment, after Ag plating to clean the plating bath in order to prevent contamination of the plating bath, in a solution containing nitric acid in a predip process, DI 85.5%, silver B 10% (10% aqueous solution of imidazole), concentrated nitric acid 2 in the Ag plating process 0.1-0.2 um thick silver by dipping silver (2.5% reagent grade), silver A 2.5% (4.5% silver nitrate, 3.5% nitric acid solution) at 50 ℃ for 8 minutes The plating layer can be formed.

In general, the plating layer can raise the thickness of 0.3 ~ 0.4 um, it can raise the thickness up to 0.1 ~ 1um according to the control of time.

In addition, the present invention may further proceed to form a plating layer by using electroless plating or electroplating as described above.

For example, when a new nickel layer is to be plated on the copper plating layer, the electrolytic nickel is plated using an aqueous solution of nickel sulfate, nickel chloride, and boric acid on a copper surface plated in the electrolytic copper plating step, and then washed with water. Ultrasonic washing with ionized water is followed by drying through dehydration to produce products that meet the required properties.

In the present invention, if the resistance value of the electrolytic plating layer is low, the electrical conductivity is increased, and if a lower resistance is required, the electrolytic copper plating may be increased to increase the content of the metal to be plated, thereby having a low resistance.

In addition, the present invention is the wiring of the patterned wiring layer so as to support the patterned wiring layer by being partially formed on the insulating layer between the step of forming the base substrate and forming the patterned wiring layer. The method may further include forming a second insulating layer along the shape.

In this case, the second insulating layer may be formed by a printing method, and more specifically, as described above with reference to the liquid thermal conductive insulating material, the second insulating layer may be printed by pad printing, silk screen printing, gravure printing, or the like. It can be formed as an insulating layer of

As described above, the second insulating layer is any one polymer selected from polybutylene terephthalate, polyethylene terephthalate, polysulfone, polyether, polyetherimide, heat resistant epoxy, polyarylate and polyimide. The resin may be selected, and the second insulating layer may have a thickness in the range of 5 um to 50 um, preferably 10 um to 20 um, and the width of the insulating layer is 1.5 to 10 times the wiring width of the wiring layer. Can be.

In addition, the present invention is different from the method shown in Figure 5, after the formation of the wiring layer on the insulating layer to form a heat dissipation layer and manufacturing the high heat-dissipation printed circuit board according to the method of attaching it to the insulating layer including the wiring layer A method can be provided which can be seen through FIG. 6.

More specifically, conductive Ag paste, conductive on any one insulating layer selected from polybutylene terephthalate, polyethylene terephthalate, polysulfone, polyether, polyetherimide, heat resistant epoxy, polyarylate and polyimide Forming a patterned wiring layer by printing a conductive paste composition including a Cu paste, a conductive polymer, and a paste for gravure or a mixture thereof in a predetermined pattern; Forming a metal plating layer on the patterned wiring layer by plating; Forming a heat dissipating layer comprising a carbon fiber fabric by heating the binder having fluidity at a high temperature to convert it into a liquid phase and filling it into an empty space formed by the weft and warp of at least one carbon fiber fabric to be used as a heat dissipating layer. ; And attaching an insulating layer including the wiring layer and the metal plating layer by the conductive paste to the heat dissipating layer.

This is different from the manufacturing method and the manufacturing method of the high heat radiation printed circuit board shown in FIG. 5 can be performed by the same process.

In addition, in the present invention, a heat dissipation coating may be additionally performed on the top and / or bottom of the finally obtained printed circuit board. In this case, there is an advantage that additional heat radiation effect of 3 ~ 5% can be obtained.

The high heat dissipation printed circuit board of the present invention can be used as a heat dissipation flexible module for LEDs because it can have reduced heat generation and improved heat dissipation, light weight, and ductility due to improved electrical conductivity.

Claims

A heat dissipation layer comprising a carbon fiber fabric;

An insulation layer formed on the heat dissipation layer;

A wiring layer formed on the insulating layer and patterned by a printing method of a conductive paste composition; And

A high heat radiation printed circuit board comprising a; metal plating layer formed on the patterned wiring layer
The method of claim 1,

The heat dissipation layer is a high heat radiation printed circuit board, characterized in that a plurality of carbon fiber fabric is laminated
The method of claim 1,

High heat radiation printed circuit board, characterized in that the half space between the warp and weft of the carbon fiber fabric is filled by a binder.
The method of claim 3,

The bonding agent is a high heat radiation printed circuit board, characterized in that epoxy or silicon based
The method of claim 3,

A high heat radiation printed circuit board, characterized in that the binder component includes a metal powder, a polymer material powder, a ceramic powder, or a mixed powder thereof having excellent thermal conductivity selected from among aluminum, copper, and nickel.
The method of claim 1,

The insulating layer is any one selected from polybutylene terephthalate, polyethylene terephthalate, polysulfone, polyether, polyetherimide, heat resistant epoxy, polyarylate and polyimide, and the thickness of the insulating layer is 10 um. High heat radiation printed circuit board, characterized in that from to 100 um
The method of claim 1,

The conductive paste composition may be any one or a mixture thereof selected from a conductive Ag paste, a conductive Cu paste, a conductive polymer, and a gravure paste.
The method of claim 1,

The metal plating layer is a high heat radiation printed circuit board, characterized in that formed by electrolytic plating or electroless plating
The method of claim 8,

The metal plating layer is formed by electroless plating, and a high heat dissipation printed circuit board, wherein a metal plating layer by electroplating is additionally formed on the plating layer formed by the electroless plating.
The method of claim 9,

A high heat dissipation printed circuit board, wherein a seed metal layer for forming an electroless metal plating layer is further formed between the patterned conductive paste wiring layer and the electroless metal plating layer.
The method of claim 1,

Between the insulating layer and the wiring layer patterned by the printing method of the conductive paste composition, a second insulating layer is additionally formed along the wiring shape of the patterned wiring layer so as to support the patterned wiring layer. High heat radiation printed circuit board
The method of claim 11,

The second insulating layer is any one selected from polybutylene terephthalate, polyethylene terephthalate, polysulfone, polyether, polyetherimide, heat resistant epoxy, polyarylate and polyimide. High heat radiation printed circuit board, characterized in that the width of the insulating layer is 1.5 to 10 times the wiring width of the patterned wiring layer.
Forming a heat dissipating layer comprising a carbon fiber fabric by heating the binder having fluidity at a high temperature to convert it into a liquid phase and filling it into an empty space formed by the weft and warp of at least one carbon fiber fabric to be used as the heat dissipating layer. step;

The base substrate is attached by attaching one insulating layer selected from polybutylene terephthalate, polyethylene terephthalate, polysulfone, polyether, polyetherimide, heat resistant epoxy, polyarylate and polyimide to the heat dissipating layer. Forming;

Forming a patterned wiring layer by printing a conductive paste composition comprising any one or a mixture thereof selected from conductive Ag paste, conductive Cu paste, conductive polymer, and gravure paste on the insulating layer of the base substrate in a predetermined pattern. step; And

Forming a metal plating layer on the patterned wiring layer by plating; and manufacturing a high heat dissipation printed circuit board.
Conductive Ag paste, Conductive Cu paste, Conductive on any insulating layer selected from polybutylene terephthalate, polyethylene terephthalate, polysulfone, polyether, polyetherimide, heat resistant epoxy, polyarylate and polyimide Forming a patterned wiring layer by printing a conductive paste composition including any one selected from a polymer and a gravure paste or a mixture thereof in a predetermined pattern;

Forming a metal plating layer on the patterned wiring layer by plating;

Forming a heat dissipating layer comprising a carbon fiber fabric by heating the binder having fluidity at a high temperature to convert it into a liquid phase and filling it into an empty space formed by the weft and warp of at least one carbon fiber fabric to be used as a heat dissipating layer. ; And

Attaching an insulating layer including a wiring layer and a metal plating layer by the conductive paste to the heat dissipating layer.
The method according to claim 13 or 14,

Between the insulating layer and the wiring layer patterned by the printing method of the conductive paste composition, further forming a second insulating layer along the wiring shape of the patterned wiring layer so as to support the patterned wiring layer. A method of manufacturing a high heat dissipation printed circuit board.
The method of claim 15,

The second insulating layer is formed of a thermally conductive liquid insulating layer by a printing method, and the width of the second insulating layer is 1.5 to 10 times the width of the wiring layer of the wiring layer. Manufacturing method.
The method according to claim 13 or 14,

A heat dissipation layer is formed on the binder component used in the forming of the heat dissipation layer, including a metal powder having excellent thermal conductivity selected from aluminum, copper, and nickel, a polymer material powder, a ceramic powder, or a mixed powder thereof. Method for producing a high heat radiation printed circuit board, characterized in that the.
The method according to claim 13 or 14,

A method of manufacturing a high heat radiation printed circuit board, characterized in that heat dissipation coating is further performed on the top and / or bottom of the finally obtained printed circuit board.
A heat radiation flexible module for an LED comprising the high heat dissipation printed circuit board according to any one of claims 1 to 12.