KR20130026830A

KR20130026830A - Adhesive

Info

Publication number: KR20130026830A
Application number: KR1020110090248A
Authority: KR
Inventors: 김덕훈; 하민기
Original assignee: 옵토팩 주식회사
Priority date: 2011-09-06
Filing date: 2011-09-06
Publication date: 2013-03-14

Abstract

PURPOSE: An adhesive is provided to improve the mechanical strength between an electronic component terminal and to obtain a stable attaching process and bonding structure with high reliability. CONSTITUTION: An adhesive(100) comprises a conductive material(110) which includes a microparticle core, a conductive metal layer surrounding the surface of the microparticle core, and a low melting point metal layer surrounding the surface of the conductive metal layer having a lower melting point than the conductive metal layer; and an adhesive resin(120) in which the conductive particle is impregnated. The conductive particle has a size of 2-20 micron. The density of the conductive particle impregnated in the conductive particle is 1,000-50,000/mm^2. The microparticle core is formed of one material selected from a metal core, inorganic microparticle core, and a polymer core.

Description

Adhesive {Adhesive}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adhesive between electronic components, which improves the bonding force between electronic components and prevents bonding errors such as conductive open and conductive short.

Anisotropic conductive film is a film in which conductive particles are mixed with an adhesive resin (generally thermosetting) to make a film and pass electricity in one direction. Nickel (Ni), gold (Au), and carbon are used as the conductive particles. Therefore, bonding using an anisotropic conductive film (hereinafter referred to as 'ACF bonding') is based on the conductive particles dispersed in the thermosetting resin and the thermosetting resin, and the electrical connection between the electrodes by the conductive particles and the thermosetting of the thermosetting resin. Mechanical connection is made.

As described above, the connection method between electronic components using an anisotropic conductive film is a lead free process, which is clean, simple, eco-friendly, and does not require instantaneous high temperature to a product (low temperature process). ) The process is more thermally stable, and lower cost can be achieved by using an inexpensive substrate such as a glass substrate or polyester flex.

Anisotropic conductive film having this advantage is mainly used to electrically connect LCD and PCB. For outer lead bonding (OLB) used when connecting a flexible substrate to a glass substrate, the flexible substrate is bonded to a printed circuit board (PCB) substrate. The market for anisotropic conductive adhesives for PCB bonding is growing.

In the mounting technology of an electronic component using an anisotropic conductive film, the connection is completed by conduction by conductive particles between electrode pads and thermosetting of the surrounding thermosetting resin, basically using a thermocompression bonding process as in Korean Patent No. 819333. In this thermocompression bonding, the movement of the conductive particles occurs by the flow of the thermosetting resin constituting the anisotropic conductive film, so that a large amount of conductive particles should be used to prevent the opening (open).

ACF bonding uses nickel and carbon conductive particles to make mechanical contacts between terminals to make electrical connections and mechanical reinforcement with an epoxy resin film. There is a problem that the reliability is poor because it is not a fusion-bonded joint.

In order to compensate for this, there is a case in which a solder ball having a single ball shape is used as the conductive particles, which is also difficult in two aspects. One is to raise the temperature to the melting temperature of the solder particles. In the display market that requires low-temperature bonding, which used ACF, there is a possibility of secondary component damage due to glass bending problems and thermal damage. Particles cannot be applied. On the other hand, when the solder particles are melted, the particles may clump together and form solder joints of the desired shape in a desired position.

The difficulty of forming a solder joint when using current conductive particles is described with reference to FIG. 1. FIG. 1 illustrates an example of a connection method between two electronic components using an adhesive of an anisotropic conductive film. In detail, FIG. 1 illustrates a conventional method for connecting two electronic components 10 and 30 to be connected as shown in FIG. Method is an adhesive 20 of an anisotropic conductive film in which the thermosetting polymer resin 22 and conductive particles 21 of FIG. 1 (b) are embedded on the upper surface on which the electrode 11 of the electronic component 10 to be connected is formed. 1C and then align with the electrode 31 of the other electronic component 30 to be connected as shown in FIG. 1C, and then apply heat and pressure (thermally pressurized) to cure the thermosetting polymer resin and to form the conductive particles 21. By doing so, the two electrodes 11 and 31 are electrically conducted.

However, in this technique, as shown in FIG. 1 (d), the conductive particles 21 are formed on the electrodes 11 and 31 by the flow of the thermosetting polymer resin in the adhesive 20 of the anisotropic conductive film generated during thermocompression bonding. Is pushed out of the electrodes 11 and 31 to cause an opening between the electrodes 11 or 31 (the area indicated by " A " in FIG. 1 (d)). In addition, there is a problem that an undesired short between the adjacent terminals (area denoted by "B" in Fig. 1 (d)) occurs due to solder delamination and agglomeration during thermocompression bonding.

An object of the present invention is to provide an adhesive containing the conductive particles proposed in the structure. In addition, the technical problem of the present invention is to prevent the conductive open and the conductive short when bonding the terminals of the two electronic components with each other by using the adhesive in which the conductive particles are embedded. In addition, the technical problem of the present invention is to improve the conduction power and bonding force of the conductive particles. In addition, the technical problem of the present invention is to improve the mechanical strength of the adhesion between the electronic component terminals.

The adhesive which is embodiment of this invention is electroconductive particle containing the microparticle core, the conductive metal layer which wraps the surface of the said microparticle core, and the low melting-point metal layer which wraps the surface of the said conductive metal layer as a material which has a melting | fusing point lower than the said conductive metal layer, and the said It contains the adhesive resin in which electroconductive particle was embedded.

Moreover, the adhesive agent which is embodiment of this invention is electroconductive particle containing the microparticle core, the electrically-conductive metal layer which surrounds the surface of the said microparticle core, and the low melting-point metal layer which encloses the surface of the said conductive metal layer as a material which has a melting | fusing point lower than the said conductive metal layer, and And a carrier polymer covering the plurality of conductive particles and extending in the longitudinal direction, and an adhesive resin in which the conductive particles and the carrier polymer are embedded.

In addition, the conductive particles have a size of 2㎛ ~ 20㎛. In addition, the density of the conductive particles embedded in the adhesive resin has a range of 1,000 pieces / mm ² ~ 50,000 pieces / mm ² .

In addition, the particulate core is formed of any one material of a metal core, an inorganic particulate core, and a polymer core.

The conductive metal layer may include gold (Au), silver (Ag), copper (Cu), platinum (Pt), zinc (Zn), iron (Fe), lead (Pb), tin (Sn), and aluminum (Al). ), Cobalt (Co), indium (In), nickel (Ni), chromium (Cr), titanium (Ti), antimony (Sb), bismuth (Bi), germanium (Ge), cadmium (Cd) and silicon (Si) ) Or at least one of these compounds.

In addition, the low melting point metal layer is a metal having a melting point of 260 ° C. or less, and includes tin (Sn), lead (Pb), bismuth (Bi), silver (Ag), zinc (Zn), indium (In), and copper. At least one or a compound thereof.

In addition, the adhesive is formed of any one of an anisotropic conductive film (ACF) and a non-conductive film (NCF) in the form of a film.

In addition, the adhesive resin is formed of at least one of epoxy resin, acryl, cyanate ester, silicone polyurethane, or a compound thereof.

In addition, the adhesive is formed of any one of an anisotropic conductive paste (ACP) and a non-conductive paste (NCP) as a paste.

The carrier polymer may further include a coating part covering the conductive particles and an extension part extending in a length direction to connect the plurality of conductive particles, and the coating part and the extension part may be connected to each other.

According to the embodiment of the present invention, by placing a particulate core such as a polymer core at the center of the conductive particles to serve as a space, the bonding force between the terminals of the two electronic components can be improved. It is also possible to improve the mechanical strength of the adhesion between the electronic component terminals. Moreover, according to embodiment of this invention, by connecting a some electroconductive particle using a fiber, an electroconductive opening and an electroconductive short can be prevented at the time of bonding the terminal of two electronic components with each other.

In addition, according to an embodiment of the present invention, by using the conductive particles including a polymer core (metal core), a metal core (metal core) by crimping and fixing the conductive particles flow between the terminal of the electronic component to prevent the solder fusion At the same time, it is possible to secure a stable bonding method and bonding structure capable of securing high reliability between electronic component terminals.

When the bonding method according to the embodiment of the present invention is used for bonding between electronic component terminals, when performing a bonding process by applying thermal compression or other energy, the particulate core of the conductive particles maintains a constant gap between the terminal and the terminal. It is fixed in the crimped state, and the metal terminal junction is pressurized by a suitable resilience force due to the crimping, so that electrical contact is made stable, and additionally, heat or energy is applied to the upper and lower conductive particles fixed by the crimping. Terminal bonding can be made to ensure a stable connection and high reliability having a solder fusion surface to the surface of the metal terminal and the conductive particles.

1 is an example illustrating a connection method between two electronic components using an adhesive of an anisotropic conductive film.
2 is a cross-sectional view of the conductive particles according to an embodiment of the present invention.
3 is an X-section SEM photograph of the conductive particles according to an embodiment of the present invention.
4 is a cross-sectional view of an adhesive having conductive particles according to an embodiment of the present invention.
5 is a cross-sectional view before and after bonding between two electronic components using an adhesive containing conductive particles of a particulate core according to an embodiment of the present invention.
FIG. 6 is a transmittance before and after bonding between two electronic components using an adhesive containing conductive particles of a fine particle core according to an embodiment of the present invention. FIG.
7 is a cross-sectional view showing a fiber according to an embodiment of the present invention.
8 is a view illustrating a shape in which fibers are irregularly arranged according to an embodiment of the present invention.
9 is a view illustrating a shape in which fibers are regularly arranged according to an embodiment of the present invention.
FIG. 10 is a view showing a state in which a fiber connecting conductive particles having a particulate core according to an embodiment of the present invention is embedded in an adhesive resin.
11 is an enlarged photograph of a fiber according to an embodiment of the present invention.
12 is a view showing a state in which two component elements are bonded by an adhesive containing conductive particles connected by a fiber according to an embodiment of the present invention.
13 is a view showing the appearance of the adhesive containing the conductive particles according to an embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings will be described an embodiment of the present invention in more detail. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various forms, and only the embodiments are intended to complete the disclosure of the present invention and to those skilled in the art to fully understand the scope of the invention. It is provided to inform you. Wherein like reference numerals refer to like elements throughout.

2 is a cross-sectional view of the conductive particles according to an embodiment of the present invention, Figure 3 is an X-section scanning electron microscope (X-section scanning electron microscope) photograph of the conductive particles according to an embodiment of the present invention 4 is a cross-sectional view of an adhesive having conductive particles according to an embodiment of the present invention.

Adhesive 100 according to an embodiment of the present invention, to maintain the conductivity between the two parts of the material through the conductive particles 110, the function of bonding, for this purpose, the conductive particles 110, the conductive particles embedded in the adhesive Resin 120. The conductive particles 110 embedded in the adhesive resin 120 include a particulate core 111, a conductive metal layer 110 covering the surface of the particulate core, and a material having a lower melting point than the conductive metal layer. It includes a low melting point metal layer 113 surrounding. That is, the electroconductive particle 110 has the microparticle core 111 in the center part, and has the structure which the conductive metal layer 110 and the low melting metal layer 110 were sequentially laminated on the surface of this microparticle core 111. The conductive particles 110 may have various shapes, such as spherical or non-spherical, depending on the purpose of the user.

The particulate core 111 located at the center of the conductive particles is implemented as particles having a volume, and is not particularly limited as a material of the particulate core. For example, a metal core, an inorganic particulate core, and a polymer core ).

The metal core is not particularly limited, for example, iron (Fe), copper (Cu), silver (Ag), gold (Au), tin (Sn), lead (Pb), platinum (Pt), nickel (Ni), titanium (Ti), cobalt (Co), chromium (Cr), aluminum (Al), zinc (Zn), tungsten (W), alloys thereof, and the like.

In addition, the material of the inorganic fine particle core is not particularly limited, for example, silica, titanium oxide, iron oxide, cobalt oxide, zinc oxide, nickel oxide ( Nickel Oxide, Manganese Oxide, Aluminum Oxide, and the like.

The polymer core is not particularly limited, and examples thereof include fine particles made of a linear polymer, organic resin particles made of a mesh polymer, microparticles made of a thermosetting resin, and fine particles made of an elastic body. Examples of the linear polymer constituting the particulate core composed of the linear polymer include nylon, polyethylene, polypropylene, methylpentene polymer, polystyrene, and polymethyl meta. Polymethylmethacrylate, polyvinyl chloride, polyvinylfluoride, polytetrafluoroethylene, polyethylene terephthalate, polybutylene terephthalate, polysulfone ), Polycarbonate, polyacrylonitrile, polyacetal, polyamide, and the like.

Examples of the mesh polymer constituting the organic resin fine particles comprising the mesh polymer include divinylbenzene, hexatoluene, divinylether, divinylsulfone, and diallyl carbinol. (diallycarbinol), alkylenediacrylate, polydiacrylate, polydimethacrylate, alkylenetriacrylate, alkylene trimethacylate, alkyl Of crosslinkable monomers such as allkylen teraacrylate, alkylene tetramethacrylate, alkylen bisacrylamide, alkylene bismethacylamide, and the like. Homopolymers, copolymers obtained by copolymerizing these crosslinkable monomers and other polymerizable monomers Polymers, and the like.

Particularly preferred polymerizable monomers include, for example, divinylbenzene, hexatoluene, divinylether, divinylsulfone, alkylene triacrylate, alkylene tetraacrylate, and the like. And alkylene teraacrylate.

Examples of the thermosetting resin constituting the thermosetting resin fine particles include phenol-benzoguanamine-formaldehyde resins, melamine-formaldehyde resins, and benzoguanamine-formaldehyde resins. (benzoguanamine-formaldehyde resins), urea-formaldehyde resins, epoxy resins, and the like.

As an elastic body which comprises the organic resin fine particle core which consists of the said elastic body, natural rubber, synthetic rubber, etc. are mentioned, for example. As for the diameter of the said fine particle core, 0.2-7000 micrometers is preferable.

Meanwhile, a conductive metal layer 110 is formed on the surface of the particulate core 111, and the conductive metal layer 110 serves to electrically conduct two electronic components to be joined. The material of the conductive metal layer is not particularly limited, but gold (Au), silver (Ag), copper (Cu), platinum (Pt), zinc (Zn), iron (Fe), lead (Pb), and tin (Sn) , Aluminum (Al), cobalt (Co), indium (In), nickel (Ni), chromium (Cr), titanium (Ti), antimony (Sb), bismuth (Bi), germanium (Ge), cadmium (Cd) And at least one metal selected from the group consisting of silicon (Si). The conductive metal layer can be preferably formed by, for example, an electroless plating method, but can also be formed by other known conductivity providing methods. The thickness of the conductive metal layer is preferably 0.001 to 50 µm. If it is less than 0.001 micrometer, sufficient electric capacity will not be obtained, and if it exceeds 50 micrometers, the performance of a base material cannot fully be utilized. More preferably, it is 0.01-10 micrometers, More preferably, it is 0.2-3 micrometers.

In addition, a low melting point metal layer 113 is formed on the surface of the conductive metal layer 110. The low melting point metal layer 113 is melted under low pressure during bonding to solder the conductive metal layers to each other. Since the low melting point metal layer 113 has a lower melting point than the conductive metal layer 110, the low melting point metal layer 113 is melted at a low temperature to bond the conductive metal layers of the plurality of conductive particles to each other.

As the material of the low melting point metal layer 113, a metal having a melting point of 260 ° C. or less, such as tin (Sn), lead (Pb), bismuth (Bi), silver (Ag), zinc (Zn), and indium (In ), One or more elements selected from copper can be used. When the low melting point metal layer is implemented as an alloy layer, one or more alloy layers of tin (Zn) -bismuth (Bi), tin (Zn) -silver (Ag), tin (Zn) -silver (Ag) -copper (Cu) In this case, it is preferable to form tin as a main component. The thickness of the low melting point metal layer is preferably 0.1 µm or more in order to obtain sufficient metal bonding. Or, it is preferably formed to a thickness of 3% to 50% of the particle diameter of the particulate core.

As described above, in the conductive particles 110, the conductive metal layer 110 and the low melting point metal layer 113 are sequentially stacked on the fine particle core 111. Such conductive particles 110 are illustrated in FIG. 4. It is embedded in the adhesive resin 120 as a plurality.

In the adhesive resin 120 of the embodiment of the present invention, various materials may be used that can easily infiltrate the conductive particles and maintain the adhesive force after a subsequent process. Preferably, a thermosetting resin or photocurable resin having a property of being cured by an external stimulus such as heat or light can be used. For example, the adhesive resin may have an initial monomer form, and may have a property of becoming a polymer while crosslinking by a thermocompression bonding process. Accordingly, the adhesive resin may be selected from at least one or a compound thereof of epoxy resin, acrylic, cyanate ester, and silicone polyurethane. In addition, the adhesive may be selectively applied to at least one or more of an anisotropic conductive film (ACF), non-conductive film (NCF) according to the purpose of use.

It is preferable that the size of the electroconductive particle 110 embedded in the adhesive resin 120 becomes 2 micrometers-20 micrometers. That is, the size of the conductive particles composed of the fine particle core, the conductive metal layer and the low melting point metal layer should be larger than 2 μm and smaller than 20 μm to maximize the conductive adhesion efficiency. It is because electroconductivity will fall when an electroconductive particle is too small, and adhesiveness will fall when an electroconductive particle is too large.

In addition, it is preferable that the diameter of the electroconductive particle 110 is adjusted suitably according to the magnitude | size of the electrical connection part of an electronic component, and the distance with an adjacent electrical connection part. For example, when there is a 200 micrometer space | interval between electrical connection parts, a comparatively large electroconductive particle, for example, electroconductive particle of 20 micrometer diameter can be used. Moreover, when the electrical pitch is between 20 micrometers-30 micrometers in fine pitch, the electroconductive particle 110 of about 3 micrometers diameter can be used. Therefore, it is preferable that the magnitude | size of the electroconductive particle contained in an adhesive resin becomes 2 micrometers-20 micrometers. That is, the size of the conductive particles composed of the fine particle core, the conductive metal layer and the low melting point metal layer should be larger than 2 μm and smaller than 20 μm to maximize the conductive adhesion efficiency.

In addition, the density of the conductive particles 110 embedded in the adhesive resin 120 is preferably set to 1,000 / mm 2 ~ 50,000 / mm 2 per adhesive resin area. If less than 1,000 conductive particles enter the 1 mm 2 adhesive resin area, open areas are formed and conductivity is lowered. On the contrary, if more than 50,000 pieces are contained in the 1 mm 2 adhesive resin area, there is a possibility that a short phenomenon occurs due to conduction to an undesired area. Because there is. In addition, it is preferable that at least three conductive particles are seated between two terminals to be joined.

For electrical connection between terminals for stable driving of electronic components, the contact resistance between terminals is required to be 1Ω or less. Therefore, even if only two or more polymer core solder balls are in contact with each other, the contact resistance of 1Ω or less can be secured. . If the contact resistance is 11Ω or more, the resistance is increased at the contact terminal, so that the required current value cannot flow.This causes the output corresponding to the terminal to be blurred or the output is different from that of the adjacent normal terminals. do. As LCD panels are increasingly demanding fine pitch / pattern, it is essential to ensure stable contact resistance between component terminals. If contact resistance is not secured, horizontal and vertical lines on the LCD screen corresponding to the corresponding terminals are required. It may cause defects that cause the camera to fall out and blur.

In addition, the adhesive having the conductive particles and the adhesive resin is preferably embedded in the weight of the conductive particles 110 to 1wt% to 50wt% in the total weight of the adhesive. The reason for limiting the weight of the conductive particles 110 as described above is to stably perform the physical bonding (attachment) between the two electronic components physically separated from each other and the function of the selective conductive particles at the same time. For example, when the content of the conductive particles 110 is larger than the above-mentioned range, short defects may occur when the electronic components are bonded, and the production cost is increased by using a large amount of the conductive particles unnecessarily. In addition, when the content of the conductive particles 110 is less than the suggested range, the electrical conductivity may not be sufficiently exhibited, which may result in open defects when the electronic components are bonded.

Meanwhile, the adhesive may be used in the form of a film as described above, but in another embodiment, the adhesive may be incorporated into a paste. When conductive particles are used in the paste, they are used for adhesives of anisotropic conductive paste (ACP) and non-conductive paste (NCP).

Hereinafter, the state at the time of joining two component elements using the adhesive resin which embedded the electroconductive particle which consists of such a particulate core, a conductive metal layer, and the low melting-point metal layer in accordance with an Example of this invention is demonstrated.

5 is a cross-sectional view before and after bonding between two electronic components using an adhesive containing conductive particles of the particulate core according to an embodiment of the present invention, Figure 6 is a conductive particle of the particulate core in accordance with an embodiment of the present invention Permeability before and after bonding between the two electronic components using the adhesive.

When the adhesive containing the conductive particles according to the embodiment of the present invention is applied between two electronic components, that is, between the upper terminal 211 and the lower terminal 221 as shown in FIG. 5 (b) and 6, the low melting point metal layer is melted to electrically connect the two terminals. The applied temperature is a low temperature at which only the low melting point metal layer can be melted, and a temperature at which the conductive metal layer cannot be melted.

The pressure applied at the time of bonding is preferably 1 to 60 MPa and heated about 1 to 10 sec. In addition, the temperature applied during bonding is made of 150 ℃ ~ 250 ℃, the temperature is applied to the high-frequency bonder (bonder) method so that the temperature is generated only around the ball (ball) to work. Therefore, there is no damage due to high heat in the substrate or the electronic component.

On the other hand, the core of the conductive particles is provided with a particulate core having a volume, it can act as a spacer during bonding to prevent the phenomenon that the plurality of conductive particles are agglomerated with each other. In other words, unlike the solder particles in the conventional ACF film that are agglomerated at the time of bonding, the conductive particles of the present invention do not agglomerate because the particulate core functions as a spacer, and the low melting point metal layer at the outermost side of the conductive particles is melted to serve as soldering. And conductive with each other through the conductive metal layer in the middle.

On the other hand, the fine particle core has a shape pressed by the pressure during bonding, but if the fine particle core has a pressed shape, it is compressed between the upper and lower terminals, thereby limiting movement and helping to maintain the position. There is no fear that the conductive particles will break out between the two terminals.

In addition, due to the pressure applied to the adhesive resin, the repulsive pressure of the fine particle core is applied toward the conductive metal layer on the surface due to the resilience of the fine particle core to stabilize the electrically conductive connection between the two terminals.

On the other hand, when the temperature (or energy) is added during the bonding bonding process, the viscosity of the epoxy material of the adhesive resin is lowered and the conductive particles in the epoxy flow together along with the flow of epoxy during bonding. Such a flow may be electrically open without any conductive particles left between terminals, and may be electrically opened. The conductive particles may accumulate and aggregate between adjacent terminals, causing short. In order to solve this problem, a method of binding conductive particles to nanofibers is proposed.

7 is a cross-sectional view showing a fiber according to an embodiment of the present invention, Figure 8 is a view showing a shape in which fibers are irregularly arranged according to an embodiment of the present invention, Figure 9 is according to an embodiment of the present invention It is a figure which shows the shape in which a fiber is arrange | positioned regularly.

As shown in FIG. 7, the fiber 130 according to the present invention extends in the longitudinal direction and exhibits various characteristics including the conductive particles 110, and includes a plurality of conductive particles 110 and the plurality of conductive particles. The carrier polymer 131 is formed to extend in the longitudinal direction while wrapping and fixing the conductive particles 110.

The conductive particles 110 are made of a fine particle core, a conductive metal layer, and a low melting point metal layer, as described above with reference to FIG. 2, and thus description thereof is omitted.

The carrier polymer 131 wraps the plurality of conductive particles 110 to physically fix the conductive particles. After the synthesis of the fiber 130, the carrier polymer 131 has a property of not decomposing (flowing like a liquid phase) during the subsequent process. . Thus, as the conductive particles 110 are wrapped and fixed to the carrier polymer 131, free movement can be suppressed. In this case, the carrier polymer 131 may be divided into a region surrounding the outer circumferential surface of each of the plurality of conductive particles 110 and a region extending in the longitudinal direction. Thus, in the following description, for convenience of description, a region of the carrier polymer 131 covering the outer circumferential surface of the conductive particles 110 is referred to as a 'coating portion 131b', ie, the remaining region except for the coating portion 131b, An area connecting between the plurality of coating parts 131b is referred to as an 'extension part 131a'. For convenience of description, the carrier polymer 131 is divided into the extension part 131a and the coating part 131b. However, the present invention is not limited thereto, and the extension part 131a and the coating part 131b are integrally connected to each other.

The coating portion 131b is preferably adjusted to a thickness so as not to interfere with the conductivity while properly fixing the conductive particles (110). The extension part 131a may vary in length depending on the content of the conductive particles 110. As the coating part 131b of the carrier polymer 131 is physically broken by a predetermined external environment change in a subsequent process using an adhesive resin, the conductive particles 110 expose the conductive particles 110 so that the conductive particles 110 are electrically conductive. Can be exercised. When bonding the electrical connection portion of the electronic component using the bonding film containing the conductive particles 110, the coating portion 131b is physically broken by the thermocompression bonding process, and the electrically conductive particles are exposed to the exposed electrically conductive particles. As a result, electricity is supplied while being in contact with the electrical connection portion of the electronic component.

The carrier polymer 131 may be made of a material that does not interfere with the conductive particles 110 exhibiting properties. For example, polyolefine, polystyrene, polyvinylalcohol, polyacrylonitrile, polyamide, polyester, aramid, acrylic Polyethylene oxide (PEO), polycaprolactone (polycaprolactone), polycarbonate (polycarbonate), polyethylene terephthalate (polyethylnenterephtalte), polybenzimidazole (PBI: polybezimidazole), poly (2-hydroethyl methacrylate ( (poly (2-hydroxyethylmethacrylate)), polyvinylidene fluoride, poly (ether imide), styrene-butadiene-styrene triblock copolymer (SBS; styrene-butadiene- styrene triblockcopolymer), poly (ferrocenyldimethylsilane), polyphenylenesulfide, polyetheretherketone Also it may be selected to be any one or a selection of these compounds.

In addition, the carrier polymer 131 and the conductive particles 110 constituting the fiber 130 are preferably maintained at a predetermined weight ratio in order to achieve the best efficiency even with the use of less conductive particles 110. For example, the weight ratio of the carrier polymer 131 and the conductive particles 110 is preferably 1: 0.25 to 25. If the weight ratio of the conductive particles 110 is less than 0.25, the electrical conductivity may not be sufficiently exhibited. If the weight ratio of the conductive particles 110 is greater than 25, too many may result in short defects when joining electronic components. This is because the production cost is increased by using a large amount of conductive particles.

In addition, the thickness of the coating portion 131b surrounding the conductive particles 110 in the carrier polymer 131 is an important factor for determining the electrical conductivity and contact resistance of the adhesive resin, and is 0.1% to 50% of the radius of the conductive particles 110. It is desirable to maintain the level.

In addition, the thickness of the coating portion 131b surrounding the conductive particles 110 in the carrier polymer 131 is 0.1% to 50% of the radius of the conductive particles 110 so that the coating portion 131b makes the conductive particles relatively uniform. It is preferably wrapped so that the coating portion 131b is easily broken during thermocompression bonding.

In addition, the diameter of the extension portion 131a of the carrier polymer 131 is preferably 10 nm to 100 μm in consideration of product quality at the time of manufacturing the adhesive resin, processability of the product at the time of thermocompression bonding, and the like. The reason for limiting the diameter of the fiber 130 extension portion 131a as described above is to maintain the dispersed state while physically fixing the coating portions 131b surrounding the conductive particles 110. For example, in the case of using the electrically conductive particles having a diameter of 20 μm as the conductive particles 110, it is preferable to keep the diameter of the fiber 130 extension part 131a at about 10 μm.

In the above description of the embodiment, the preferred conditions for the diameter of the conductive particles included in the fiber, the thickness of the coating portion of the carrier polymer, and the length of the extension part are given. However, when the particles having different properties are used as the conductive particles, the diameter of the conductive particles, the carrier Coating thickness and extension length of the polymer may be implemented in various ways without being limited to the conditions presented.

On the other hand, the fiber 130 may be composed of one strand, but as the plurality of fibers 130 are entangled with each other to form a net structure to more effectively suppress the movement of the conductive particles 110 included in the fiber 130 Can be. Hereinafter, for convenience of description, a form in which the plurality of fibers 130 are entangled with each other will be referred to as a fiber assembly 130A. The fiber assembly 130A has a net structure in which a plurality of fibers 130 are irregularly woven or regularly woven together. That is, the fiber assembly 130A may be in a state in which the fibers 130 are tangled with each other as shown in FIG. 8, and some of the fibers 130 are arranged in a horizontal direction as shown in FIG. 9, and the others are arranged in a vertical direction. It can be arranged as arranged. Preferably there may be a fabric structure in which the fibers 130 are arranged in a weft and warp arrangement of fabric structures.

In this way, the fibers 130 connecting the plurality of conductive particles having the fine particle core may be formed to have a predetermined thickness and area as they are embedded in the above-described adhesive resin (see FIG. 10), and thus, the fiber assembly 130A. ) Can improve the mechanical strength.

For reference, FIG. 11 is an enlarged photograph of a fiber according to an embodiment of the present invention, and FIG. 12 is a view in which two component elements are bonded by an adhesive containing conductive particles connected by a fiber according to an embodiment of the present invention. This is a picture showing.

While applying heat to the first and second terminals 211 and 221 and the adhesive 100, pressure is applied from the upper side to the lower side of the first electronic component 210 and from the lower side to the upper side of the second electronic component 220. do. At this time, the heating and pressurization time is preferably several seconds to several tens of seconds, the heating temperature is preferably 150 ~ 250 ℃, the compression pressure is preferably about 1 ~ 60Mpa, the heating time is preferably 1sec ~ 10sec.

When the thermal compression process is performed as described above, the first terminal 211 of the first electronic component 210 and the second terminal 221 of the second electronic component 220 are adhesive as shown in FIG. 12. It is embedded into 100. In addition, an area where the first terminal 211 is not formed in the upper middle part of the first electronic component 210 and an area where the second terminal 221 is not formed in the upper middle part of the second electronic component 220 may be formed of an adhesive ( The upper and lower portions of the junction portion 100b are bonded to each other. Accordingly, the compression pressure applied through the first and second electronic components 210 and 220 is transmitted to the adhesive 100.

At this time, a flow (or flow) of the adhesive 100 is generated by the compression pressure transmitted to the adhesive 100. Preferably, it flows from an area between the first terminal 211 and the second terminal 221 to a region other than between the first terminal 211 and the second terminal 221. However, the fiber 130, which is entangled in a mesh structure, is inhibited in movement despite the flow of the adhesive 109, and thus the movement of the conductive particles 110 is also suppressed.

In addition, compared to the separation distance between the upper surface of the first electronic component 210 without the first terminal 211 and the lower surface of the second electronic component 220 without the second terminal 221, The separation distance between the first terminal 211 and the second terminal 212 is close.

Accordingly, the recessed portion 100a region located between the first terminal 211 and the second terminal 212 of the entire region of the adhesive 100 receives a greater compression pressure than other regions. Therefore, as shown in the enlarged view of FIG. 12, the carrier polymer 131 surrounding the conductive particles 110 positioned between the first terminal 211 and the second terminal 212 by the pressure transmitted to the adhesive 100, that is, The coating part 131b is physically broken, and the conductive particles 110 are exposed.

As the coating part 131b is physically cracked, the first particles 211 and the second terminals 212 are electrically connected to each other by the conductive particles 110, and electrical conduction is performed. In addition, the coating part 131b positioned between the region where the first terminal 211 and the second terminal 212 are not formed is not broken. As a result, a position where electrical conduction is not desired, that is, a region of the first electronic component 210 where the first terminal 211 is not formed and a region of the second electronic component 220 where the second terminal 221 is not formed are energized. Can be prevented. That is, it is possible to prevent the occurrence of electrical short. As such, the adhesive 100 including the fiber 130 according to the present invention can be easily bonded between the pair of electronic components 210 and 220. That is, by using the fiber 130 having the conductive particles 110 fixed therein, the movement of the conductive particles 110 is suppressed during the thermocompression bonding process, thereby opening and closing the pair of electronic components 210 and 220. Short can be prevented. In addition, even if the sizes of the first and second terminals 211 and 221 are reduced, it is possible to easily conduct electricity between the first terminal 211 and the second terminal 221 by using conductive particles having the same diameter. have. In addition, the conductive particles 110 of the fiber 130 is physically fixed to the carrier polymer 131, the fiber 130 itself is tangled or irregularly tangled, there is a strong advantage against external physical impact .

13 is a view showing the appearance of the adhesive containing the conductive particles according to an embodiment of the present invention.

The shape of the conductive particles 110 embedded in the adhesive 100 may have various shapes such as a sphere 110a or a non-spherical non-spherical 110b according to a user's purpose. The particulate core of the conductive particles may be implemented with a polymer core 111a or a metal core 112.

In addition, the adhesive 100 may be implemented in the form of a film such as an anisotropic conductive film (ACF) or a non-conductive film (NCF). Alternatively, the adhesive may be prepared in the form of a paste having fluidity, and may be implemented as a paste such as an anisotropic conductive paste (ACP) or a non-conductive paste (NCP). For example, a carrier polymer in a liquid form and a fiber may be mixed to prepare a mixture for preparing an adhesive, and heated to a predetermined temperature to increase the viscosity to prepare an adhesive in a paste form. In addition, the paste-type adhesive may be used, for example, by applying a dispenser for dispensing and dispensing a processed material.

In addition, as the conductive particles are described with reference to FIGS. 7 to 12, a plurality of conductive particles are connected by a fiber and embedded in an adhesive, thereby improving adhesion and conductivity between two component elements.

Although the present invention has been described with reference to the accompanying drawings and the preferred embodiments described above, the present invention is not limited thereto but is limited by the following claims. Accordingly, those skilled in the art will appreciate that various modifications and changes may be made thereto without departing from the spirit of the following claims.

100: adhesive 110: conductive particles
111: particulate core 112: conductive metal layer
113: low melting point metal layer 120: adhesive resin
130: fiber

Claims

Conductive particles including a particulate core, a conductive metal layer surrounding the surface of the particulate core, and a low melting point metal layer surrounding the surface of the conductive metal layer as a material having a lower melting point than the conductive metal layer;
An adhesive resin in which the conductive particles are embedded;
Adhesive comprising.

Conductive particles including a particulate core, a conductive metal layer surrounding the surface of the particulate core, and a low melting point metal layer surrounding the surface of the conductive metal layer as a material having a lower melting point than the conductive metal layer;
A carrier polymer covering the plurality of conductive particles and extending in the longitudinal direction;
An adhesive resin in which the conductive particles and the carrier polymer are embedded;
Adhesive comprising.

The adhesive according to claim 1 or 2, wherein the conductive particles have a size of 2 µm to 20 µm.

The adhesive according to claim 1 or 2, wherein the density of the conductive particles embedded in the adhesive resin has a range of 1,000 / mm ² to 50,000 / mm ² .

The adhesive of claim 1 or 2, wherein the particulate core is formed of any one of a metal core, an inorganic particulate core, and a polymer core.

The method of claim 5, wherein the metal core is iron (Fe), copper (Cu), silver (Ag), gold (Au), tin (Sn), lead (Pb), platinum (Pt), nickel (Ni), Adhesive formed of at least one of titanium (Ti), cobalt (Co), chromium (Cr), aluminum (Al), zinc (Zn), tungsten (W) or alloys thereof.

The method of claim 5, wherein the inorganic fine particle core, silica, titanium oxide, iron oxide (iron oxide), cobalt oxide (Cobalt Oxide), zinc oxide (Zinc Oxide), nickel oxide (Nickel Oxide), Adhesive formed of at least one of manganese oxide and aluminum oxide.

The adhesive according to claim 5, wherein the polymer core is at least one of fine particles made of a linear polymer, organic resin particles made of a mesh polymer, fine particles made of a thermosetting resin, and fine particles made of an elastic body.

The linear polymer of claim 8, wherein the linear polymer constituting the fine particles comprising the linear polymer includes nylon, polyethylene, polypropylene, methylpentene polymer, polystyrene, and poly. Methyl methacrylate, polyvinyl chloride, polyvinyl fluoride, polytetrafluoroethylene, polyethylene terephthalate, polybutylene terephthalate, polysulfone adhesive formed of at least one of polysulfone, polycarbonate, polyacrylonitrile, polyacetal, polyamide, or a compound thereof.

The mesh polymer constituting the organic resin fine particles comprising the mesh polymer is divinylbenzene, hexatoluene, divinylether, divinylsulfone, di Allylcarbinol, alkylenediacrylate, polydiacrylate, polydimethacrylate, alkylenetriacrylate, alkylene trimethacylate Crosslinkable monomers such as alkylene tetraacrylate, alkylene tetramethacrylate, alkylen bisacrylamide, alkylene bismethacylamide, and the like. homopolymers of monomers), obtained by copolymerizing these crosslinkable monomers and other polymerizable monomers. Adhesive formed from at least one of the copolymers or compounds thereof.

The thermosetting resin constituting the thermosetting resin microparticles according to claim 8, phenol-benzoguanamine-formaldehyde resins, melamine-formaldehyde resins, benzoguanamine-form Adhesive formed of at least one of aldehyde resins (benzoguanamine-formaldehyde resins), urea-formaldehyde resins, epoxy resins or compounds thereof.

The adhesive according to claim 8, wherein the elastic body is formed of at least one of natural rubber and synthetic rubber or a compound thereof.

The method of claim 1 or 2, wherein the conductive metal layer is gold (Au), silver (Ag), copper (Cu), platinum (Pt), zinc (Zn), iron (Fe), lead (Pb), tin ( Sn), aluminum (Al), cobalt (Co), indium (In), nickel (Ni), chromium (Cr), titanium (Ti), antimony (Sb), bismuth (Bi), germanium (Ge), cadmium ( Adhesive formed from at least one of Cd) and silicon (Si) or a compound thereof.

The said low melting metal layer is an adhesive agent of Claim 1 or 2 which is a metal which has melting | fusing point 260 degrees C or less.

The method of claim 14, wherein the low-melting metal layer is tin (Sn), lead (Pb), bismuth (Bi), silver (Ag), zinc (Zn), indium (In), copper, or at least one of these compounds Adhesive formed with.

The adhesive of claim 1 or 2, wherein the adhesive is formed of any one of an anisotropic conductive film (ACF) and a non-conductive film (NCF) in the form of a film.

The adhesive of claim 16 wherein the adhesive resin is at least one of epoxy resins, acrylics, cyanate esters, silicone polyurethanes or compounds thereof.

The adhesive of claim 1 or 2, wherein the adhesive is formed of any one of an anisotropic conductive paste (ACP) and a non-conductive paste (NCP) as a paste.

The adhesive of claim 2, wherein the carrier polymer includes a coating part covering the conductive particles and an extension part extending in a longitudinal direction to connect the plurality of conductive particles, wherein the coating part and the extension part are connected to each other.

The method according to claim 2 or 19, wherein the carrier polymer is made of a polymer material, polyolefin (polyolefine), polystyrene (polystyrene), polyvinyl alcohol (polyvinylalcohol), polyacrylonitrile (polyacrylonitrile), polyamide (polyamide), Polyester, aramid, acrylic, acrylic, polyethylene oxide (PEO), polycaprolactone, polycarbonate, polyethylene terephthalate, polybenzimidazole PBI: polybezimidazole), poly (2-hydroxyethylmethacrylate), polyvinylidene fluoride, poly (ether imide), styrene Butadiene-styrene triblock copolymer (SBS; styrene-butadiene-styrene triblockcopolymer), poly (ferrocenyldimethylsilane), polypeptide Renseo sulfide (polyphenylenesulfide), polyimide sseoyi written adhesive formed of at least any one or a compound of the ketone (polyetheretherketone).