TWI544055B - Anisotropic conductive film composition, anisotropic conductive film and semiconductor device - Google Patents

Description

Anisotropic conductive film composition, anisotropic conductive film, and semiconductor device Field of invention

The present invention relates to an anisotropic conductive film composition, an anisotropic conductive film produced therefrom, and a semiconductor device. More particularly, the present invention relates to an anisotropic conductive film composition comprising: a binder comprising a polyester urethane resin, a urethane acrylate resin, and a polyester urethane resin and the like At least one of urethane acrylate resins; at least one of ethylene-vinyl acetate copolymer; a radical polymerizable material comprising tricyclodecane dimethanol diacrylate or tricyclodecane dimethanol Methacrylate; and organic particles. In particular, the present invention relates to a resin composition for connecting a circuit and a film having an elongation of 10 to 100% after curing and inconspicuous shrinkage and expansion in a joint structure, whereby Avoid the reduction of electrical connection reliability under high temperature and high humidity.

Related technical description

Generally, an anisotropic conductive film (ACF) refers to a film-like adhesive in which conductive particles are dispersed, such as metal particles containing nickel or gold particles. When an anisotropic conductive film is placed between the boards to be connected and subjected to heating and pressurization under special conditions, the circuit terminals of the circuit board are electrically connected via conductive particles, and an insulating adhesive resin is Filled between the adjacent circuit terminals to isolate the conductive particles from each other, thereby providing high insulation between the circuit terminals.

These anisotropic conductive films are widely used to make a liquid crystal display (LCD) panel and a chip-on-film (COF) or a tape carrier package (TCP). Electrically connect or connect a circuit board (PCB) to a COF or TCP.

The conventional anisotropic conductive film is classified into an epoxy type and a (meth) acrylate type, wherein the epoxy type is a binder resin system as a substrate for forming a film and an epoxy or phenol resin curing agent. a curing system comprising: a (meth) acrylate type comprising a binder resin system and a curing system comprising a (meth)acrylic oligomer, a monomer, and a radical Starting agent.

However, a binder system of a conventional anisotropic conductive film serves only as a film former that does not substantially contribute to the initial adhesion or connection reliability. Furthermore, since the binder system generally comprises a polymer resin having a low glass transition temperature, which repeatedly contracts and expands in a joint structure, long-term connection and adhesion reliability cannot be ensured.

An anisotropic conductive film needs to exhibit satisfactory adhesion. In order to increase the adhesion of an anisotropic conductive film, a high molecular weight polyurethane resin may be added. However, in this case, the poor compatibility of the high molecular weight polyurethane resin with other components such as an acrylic binder or a low molecular weight (meth) acrylate makes it difficult to form an anisotropic conductive film.

Furthermore, an anisotropic conductive film needs no significant shrinkage or expansion in a connection structure to achieve good reliability in electrical connection under high temperature and high humidity. However, since a typical anisotropic conductive film is liable to shrink or expand upon curing, the reliability for increasing the anisotropic conductive film is limited.

Korean Patent Publication No. 2008-0060613 discloses a composition for anisotropic conductive film having improved fluidity and adhesion, comprising a film-forming polymer resin, an ethylene-vinyl acetate copolymer, and a free a polymerizable material, and a free radical initiator. When the radical polymerizable material is used in a large amount, for example, 40 to 70% by weight as shown in this publication, the adhesion of the film is reduced. Further, when the film-forming polymer resin is added in a small amount, for example, 10 to 30% by weight, the film becomes quite soft, causing a problem of workability.

Accordingly, there is a need for an anisotropic conductive film composition comprising a component which is compatible with a polyurethane adhesive or a urethane acrylate, which maintains excellent adhesion under conditions of rapid final pressing and has low elongation. Rate to improve connection reliability.

Summary of invention

The object of the present invention is to overcome the aforementioned problems, and an aspect of the invention provides an anisotropic conductive film which does not significantly shrink and expand in a joint structure due to low elongation after curing, thereby avoiding high temperature and high The reliability of the electrical connection under humidity is reduced, and a composition for this.

Another aspect of the present invention provides an anisotropic conductive film composition capable of suppressing an increase in connection resistance due to a decrease in fluidity, and having stable conductivity, and maintaining excellent adhesion under rapid final pressing conditions.

According to an aspect of the invention, there is provided an anisotropic conductive adhesive film having an elongation of 10 to 100% after curing, and comprising: a solid content of 40 to 80% by weight based on the total weight of the film a binder resin comprising a polyester urethane resin, a urethane acrylate resin, and the like At least one of a polyester urethane resin and a urethane resin of one of the urethane acrylate resins; and an organic particle.

According to another aspect of the present invention, there is provided an anisotropic conductive film composition comprising: a binder comprising a polyester urethane resin, a urethane acrylate resin, and a polyester urethane resin and the polyurethane At least one of urethane resins; one ethylene-vinyl acetate copolymer; a radical polymerizable material comprising tricyclodecane dimethanol diacrylate or tricyclodecane dimethanol Acrylate; and organic particles.

The anisotropic conductive film according to the present invention and the composition for the film do not significantly shrink and expand in a joint structure, thereby avoiding reduction in electrical connection reliability at high temperatures and high humidity.

Further, the anisotropic conductive film and the composition for the film maintain excellent adhesion under conditions of rapid final pressing.

Further, the anisotropic conductive film and the composition for the film have remarkably improved fluidity, heat resistance, and reliability.

Detailed description of the invention

Exemplary embodiments of the invention will now be described in detail. However, the examples are for illustrative purposes only and are not to be construed as limiting the scope of the invention. The scope of the invention is to be limited only by the scope of the appended claims and their equivalents.

In the following description, unless otherwise indicated, the content of each component will be stated in terms of solid content.

One aspect of the present invention provides an anisotropic conductive film composition, which comprises The invention comprises: a binder comprising at least one of a polyester urethane resin, a urethane acrylate resin, and a urethane resin other than the polyester urethane resin and the urethane acrylate resin; and an ethylene-vinyl acetate An ester copolymer; a radically polymerizable material comprising tricyclodecane dimethanol diacrylate or tricyclodecane dimethanol dimethacrylate; and organic particles.

As a radical polymerizable material, tricyclodecane dimethanol diacrylate and tricyclodecane dimethanol dimethacrylate are each represented by Chemical Formulas 1 and 2, which are effective for improving the heat resistance of the anisotropic conductive film composition. Sex and reliability.

The radical polymerizable material may be present in an amount of 10 to 40% by weight (wt%) based on the solid content, based on the total amount of the composition. Within this range, proper adhesion and connection reliability can be obtained after final compression.

When the radical polymerizable material is used in a large amount as described above, the adhesion of the anisotropic conductive film composition is slightly reduced. Therefore, in the present invention, an ethylene-vinyl acetate (EVA) copolymer having high adhesion is added to make up Reducing the reduced adhesion caused by free radical polymerizable materials.

The EVA copolymer is obtained by copolymerization of ethylene and vinyl acetate to obtain a thermoplastic resin which has an effect of improving the fluidity and adhesion of the composition. Preferably, the vinyl acetate is present in the EVA copolymer in an amount from 15 to 35 weight percent. Within this range, the fluidity is increased, the adhesion is excellent, and the appropriate elastic modulus and reliability are exhibited.

When a large amount of EVA copolymer is added to the composition, excessive fluidity hinders the adhesive resin from filling the gap between the circuits, thereby reducing the adhesion and increasing the reliability after testing at 85 ° C and 85 RH%. Connect the resistor. In the present invention, the organic particles are further added to the composition, whereby the excessive fluidity of the composition caused by the EVA copolymer is compensated. Further, the organic particles alleviate the stress accompanying the heat shrinkage and reduce the thermal deformation due to shrinkage and expansion, thereby maintaining the adhesion reliability under high temperature and high humidity.

The anisotropic conductive film composition according to the present invention may further comprise a component generally used for an anisotropic conductive film composition, for example, a radical initiator and conductive particles.

In the present invention, the anisotropic conductive film composition may comprise 40 to 80% by weight of the binder, 5 to 30% by weight of the EVA copolymer, and 10 to 40% by weight based on the total weight of the composition. A radical polymerizable material, and 1 to 10% by weight of organic particles.

The organic particles may have a single layer or a plurality of layers.

In one embodiment, the organic particles comprise a copolymer selected from the group consisting of styrene-divinylbenzene copolymer, chlorinated polyethylene, dimethyl polyoxyalkylene, methyl methacrylate- Acrylate butyl-dimethyloxane copolymer, styrene-butadiene-styrene block copolymer, styrene-butadiene thermoplastic elastomer, butadiene rubber, styrene-butadiene rubber And at least one of the group consisting of ethylene-glycidyl methacrylate copolymer.

In particular, the organic particles having a single layer structure may be spherical organic particles composed of a crosslinked urethane resin. Polyurethane organic particles can be obtained by ion exchange treatment. The ion exchange treatment of the polyurethane organic particles can be carried out by any method generally known in the art, for example, a dilution method using a solvent, or a method using a monomer which does not generate residual ions. The ion content of the polyurethane organic particles, which is preferably greater than 0 and 10 ppm or less, more preferably from 1 to 10 ppm, is reduced by ion exchange treatment. In this range, when connected to a circuit, the conductivity of the film does not become high and corrosion does not occur.

In one embodiment, organic particles comprising a copolymer of methyl methacrylate, styrene and divinylbenzene, and a copolymer of methyl methacrylate, styrene and butadiene may be used.

The multilayer organic particles may have a two or three layer structure comprising a core and a shell. For example, in the second layer of organic particles, the polymer resin forming the core has a lower glass transition temperature than the polymer resin forming the shell. In more detail, the organic particles are composed of a core and a shell, wherein the core comprises a rubbery polymer having a low glass transition temperature, for example, a homopolymer or a copolymer of an acrylic monomer, and the shell comprises A polymer having a high glass transition temperature. Since the shell having a high glass transition temperature restricts particle fusion and improves the compatibility with the matrix resin, the organic particles are easily dispersed and the viscosity can be controlled, thereby ensuring liquid stability and sufficient processability. Any acrylic The monomer can be used to form organic particles having this multilayer structure.

The diameter of the organic particles is not particularly limited, and may be, for example, 0.1 to 10 μm, preferably 0.3 to 5 μm. Within this range, the organic particles can be appropriately dispersed without interfering with the conductivity of the conductive particles.

The organic particles may be present in an amount of from 1 to 10% by weight based on the total weight of the anisotropic conductive film composition in terms of solid content. If the amount of the organic particles is less than 1% by weight, the organic particles have almost no effect. If the content is more than 10% by weight, the film viscosity is reduced, resulting in deterioration of the preliminary pressing property.

Furthermore, another aspect of the present invention provides an anisotropic conductive adhesive film having an elongation of 10 to 100% after curing, and comprising 40 to 80 in terms of solid content based on the total weight of the film. One part by weight of a binder resin comprising at least one of a polyester urethane resin, a urethane acrylate resin, and a urethane resin; and organic particles.

In the present invention, an elongation of 10 to 100% after curing is related to a low shrinkage or expansion ratio in a joint structure, which avoids a reduction in electrical connection reliability at high temperatures and high humidity. Elongation was measured on a sample of a 5N load cell placed on it by means of a clamp and measured using a universal test machine (UTM) at a tensile test speed of 50 mm/min.

The binder resin containing at least one of a polyester urethane resin, a urethane acrylate resin, and a urethane resin may be present in an amount of 40 to 80% by weight based on the total weight of the composition or the film. If the content of the binder resin is less than 40% by weight, the film system is relatively soft, causing problems in terms of workability. If the content is more than 80% by weight, the fluidity may be deteriorated.

Initially pressed at 70 ° C and 1.0 MPa for 1 second and at 150 ° C and 4.0 MPa After 4 seconds of pressing, the anisotropic conductive adhesive film had an adhesive strength of 800 gf/cm or more. In one embodiment, the bond strength can be 900 gf/cm or higher. Even after pressing at 150 ° C, the adhesive film has a bonding strength of 800 gf / cm or more, which is lower than that at 200 ° C and 4.0 MPa for 4 seconds, so that the use of high adhesion after rapid final pressing is maintained. strength.

Calculated in Equation 1, the anisotropic conductive adhesive film has an increased connection resistance of greater than 0 and 40% or less: an increase in connection resistance (%) = (AB) / A × 100, wherein A is at 70 ° C And the connection resistance of 1.0 MPa initially pressed for 1 second and finally pressed at 150 ° C and 4.0 MPa for 4 seconds, and the B series is initially pressed, finally pressed, and then connected at 85 ° C and 85% RH reliability test for 500 hours. resistance.

Hereinafter, each component of the anisotropic conductive film composition according to the present invention will be described in detail.

Adhesive resin

The binder resin serves as a binder system for forming a matrix required for an anisotropic conductive film. The binder resin may comprise a polyester urethane resin, a urethane acrylate resin, and at least one of the polyester urethane resin and the urethane resin of the urethane acrylate resin, based on the total weight of the solid film. It may be present in an amount of 40 to 80% by weight.

In particular, the anisotropic conductive film composition of the present invention may contain a polyester urethane resin or a urethane acrylate resin as a thermoplastic resin based on fluidity and adhesion. Because the binder system has a low glass transition temperature, the composition exhibits improved fluidity and, therefore, exhibits a urethane group within the molecular chain. It is now highly adhesive. In particular, when a polyester urethane resin or a urethane acrylate resin is used for the anisotropic conductive film, the curing property is enhanced, whereby the temperature of the joining treatment is lowered.

Polyester urethane resin

The polyester urethane resin used in the present invention can be obtained by reacting a polyester polyol with a diisocyanate.

Polyester polyol refers to a polymer having a plurality of ester groups and a plurality of hydroxyl groups. The polyester polyol can be obtained by reacting a dicarboxylic acid with a glycol.

Examples of the dicarboxylic acid include terephthalic acid, isophthalic acid, adipic acid, sebacic acid, succinic acid, glutaric acid, suberic acid, sebacic acid, dodecanedicarboxylic acid, hexahydroortho Phthalic acid, phthalic acid, tetrachlorophthalic acid, 1,5-naphthalene dicarboxylic acid, fumaric acid, maleic acid, itaconic acid, citraconic acid, mesaconic acid, and tetrahydroortylene Formic acid. Preferably, an aromatic or aliphatic dicarboxylic acid is used.

Examples of the glycol include ethylene glycol, propylene glycol, hexanediol, neopentyl glycol, diethylene glycol, triethylene glycol, 1,3-propanediol, 1,3-butanediol, and 1,4-butylene. Glycol, 1,5-pentanediol, 1,6-hexanediol, dipropylene glycol, dibutylene glycol, 2-methyl-1,3-pentanediol, 2,2,4-trimethyl- 1,3-pentanediol, and 1,4-cyclohexanedimethanol. These are preferably diols.

The diisocyanate may include aromatic, aliphatic, alicyclic diisocyanates, and the like. Examples of such diisocyanates include isophorone diisocyanate (IPDI), tetra-methyl-1,4-diisocyanate, hexamethylene-1,6-diisocyanate, diphenylmethane diisocyanate, and extensible rings. Hexyl-1,4-diisocyanate, methyl bis(4-cyclohexyl isocyanate), xylene diisocyanate, hydrogenated diphenylmethane diisocyanate, naphthalene diisocyanate, and 2,4- Or 2,6-toluene diisocyanate, which may be used singly or in a mixture. Preferably, an aromatic diisocyanate is used.

The polyester urethane resin may have a weight average molecular weight of 10,000 to 100,000, preferably 25,000 to 70,000.

Urethane acrylate resin

The anisotropic conductive film composition may include a urethane acrylate resin as a thermoplastic resin based on fluidity and adhesion.

Since the urethane acrylate resin in the binder system has a low glass transition temperature, the composition exhibits improved fluidity and, therefore, exhibits high adhesion due to urethane groups in the molecular chain. In particular, when a urethane acrylate resin is used for the anisotropic conductive film, the curing property is enhanced, whereby the temperature of the joining treatment is lowered.

The urethane acrylate resin may include a diisocyanate, a polyol (or a diol), and an acrylate, but is not limited thereto.

The diisocyanate may comprise an aromatic, aliphatic, cycloaliphatic diisocyanate, and mixtures thereof. Examples of the diisocyanate include tetramethyl-1,4-diisocyanate, hexamethylene-1,6-diisocyanate, cyclohexyl-1,4-diisocyanate, methyl bis(4-cyclohexyl isocyanate) ), isophorone diisocyanate, and 4,4'-methyl bis(cyclohexyl isocyanate), which may be used singly or in a mixture thereof.

The polyol may include a polyether polyol and a polycarbonate polyol which may have at least two hydroxyl groups in its molecular chain. As the polyether polyol, a polyol having a weight average molecular weight of 400 to 10,000 g/mole, preferably 400 to 3,000 g/mol, may be used. As a polycarbonate polyol, it can be used Polyalkylene carbonate and self-derivative polycarbonate polyol.

The diol may include 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, diethylene glycol Alcohol, dipropylene glycol, triethylene glycol, tetraethylene glycol, dibutyl glycol, 2-methyl-1,3-pentanediol, 2,2,4-trimethyl-1,3-pentanediol And 1,4-cyclohexanedimethanol.

Acrylates can include hydroxy acrylates and amine acrylates.

The urethane acrylate resin comprising the above three components is subjected to addition polymerization such that the molar ratio of the isocyanate group (NCO) to the hydroxyl group (OH) is 1.04 to 1.6, and the three components other than the acrylate are interposed. a polyol content of 70% or less, which is followed by a terminal functional group (ie, an isocyanate group) of a urethane synthesized by addition polymerization and a hydroxy acrylate or amine acrylate of 0.1 to 2.1. The molar ratio is prepared in response to the reaction. In addition, the remaining isocyanate groups are reacted with an alcohol, thereby producing a final urethane acrylate resin. Here, the addition polymerization can be carried out by any method generally known in the art. Further, the addition polymerization can be carried out using a tin-based catalyst at 90 ° C and 1 atm for 5 hours, but is not limited thereto.

That is, the urethane acrylate resin has a single glass transition temperature of 0 ° C or higher, or at least one of 0 ° C or higher due to the mixing of a polyol of a soft section and a diisocyanate of a hard section. The glass transition temperature, and therefore, acts as a binder for forming a film at room temperature. Further, the urethane acrylate resin is cured as a curing system together with the propylene group of the curing system via the acrylate group present in the terminal functional group, thereby exhibiting excellent adhesion and high connection reliability.

Polyurethane acrylate resin can have 10,000 to 100,000 g/m The ear is preferably a weight average molecular weight of 20,000 to 40,000 g/mole. The urethane acrylate resin has a two glass transition temperature (Tg), at least one of which may be 0 ° C or higher.

Urethane resin

The urethane resin is a polymer resin having one urethane bond other than the polyester urethane resin and the urethane acrylate resin. The urethane resin can be obtained, for example, by a polymerization reaction of isophorone diisocyanate, polytetraethylene glycol or the like, but is not limited thereto. The urethane resin may have a weight average molecular weight of 50,000 to 100,000 g/mole.

The binder resin may be present in an amount of 40 to 80% by weight, preferably 45 to 75% by weight based on the total weight of the solid anisotropic conductive film composition. Further, based on the excellent adhesion and reliability, the weight ratio between the binder resin and the radical polymerizable material may be from 2:1 to 12:1, preferably from 2.5:1 to 7:1, in terms of solid content.

Free radical polymerizable material

As a radical polymerizable material, tricyclodecane dimethanol diacrylate and tricyclodecane dimethanol dimethacrylate are each represented by Chemical Formulas 1 and 2, which are effective for improving an anisotropic conductive film composition. Heat resistance and reliability.

The radical polymerizable material may be present in an amount of 10 to 40% by weight based on the total weight of the composition. Within this range, proper adhesion and connection reliability can be obtained after final compression.

In one embodiment, the anisotropic conductive film or the composition for the film according to the present invention may further contain one of the universal use of the art, in addition to the radical polymerizable material represented by Chemical Formula 1 or 2. A polymerizable material. Examples of such radically polymerizable materials include acrylates, methacrylates, and maleimide compounds, which may be monomers, oligomers, polymers, or monomers, oligomers or polymers. The mixture is used, but is not limited thereto.

Ethylene-vinyl acetate copolymer

The EVA copolymer is obtained by copolymerization of ethylene and vinyl acetate to obtain a thermoplastic resin which has an effect of improving the fluidity and adhesion of the composition.

In one embodiment, the EVA copolymer may be a material exhibiting excellent fluidity and having a weight average molecular weight of about 100,000 to 600,000, which is suitable for hot pressing applied to an anisotropic conductive film. In particular, within this range, the appropriate strength and intermixability with other resins forming the film can be exhibited.

In the EVA copolymer, vinyl acetate can be stored in an amount of 15 to 35 wt% in. Within this range, fluidity is increased, excellent adhesion properties can be exhibited, and appropriate elastic modulus and reliability can be obtained.

The EVA copolymer may be present in an amount of from 5 to 30% by weight, preferably from 5 to 20% by weight, based on the total amount of the composition. Within this range, fluidity can be improved and a near-cured structure can be formed.

Organic particles

The organic particles are used to compensate for the excessive fluidity of the composition caused by the EVA copolymer. Further, the organic particles alleviate the stress under the heat shrinkage accompanying the curing, and reduce the thermal deformation due to shrinkage and expansion, thereby imparting adhesion reliability to the film at high temperature and high humidity.

The organic particles may have a single layer or a plurality of layers.

In one embodiment, the organic particles comprise a copolymer selected from the group consisting of styrene-divinylbenzene copolymer, chlorinated polyethylene, dimethyl polyoxyalkylene, methyl methacrylate-butyl acrylate-dimethyl siloxane. , styrene-butadiene-styrene block copolymer, styrene-butadiene thermoplastic elastomer, butadiene rubber, styrene-butadiene rubber, and ethylene glycidyl methacrylate copolymer Form at least one of the ethnic groups.

In particular, the organic particles having a single layer structure may be spherical organic particles comprising a crosslinked urethane resin. Polyurethane organic particles can be obtained by ion exchange treatment. The ion exchange treatment of the polyurethane organic particles can be carried out by any method generally known in the art, for example, a dilution method using a solvent, or a method using a monomer which does not generate residual ions. The ion content of the polyurethane organic particles is reduced by ion exchange treatment, which is preferably greater than 0 and 10 ppm or less. In this range, when connected to a circuit, The conductivity of the film does not become high and corrosion does not occur.

The multilayered organic particles may have a two or three layer structure comprising a core and a shell. For example, in the second layer of organic particles, the polymer resin forming the core has a lower glass transition temperature than the polymer resin forming the shell. In more detail, the organic particles are composed of a core and a shell, wherein the core comprises a rubbery polymer having a low glass transition temperature, for example, a homopolymer or a copolymer of an acrylic monomer, and the shell is Contains polymers with high glass transition temperatures. Since the shell having a high glass transition temperature restricts particle fusion and improves compatibility with the matrix resin, the organic particles are easily dispersed and the viscosity can be controlled, thereby ensuring liquid stability and sufficient processability. Any acrylic monomer can be used to form organic particles having this multilayer structure.

The diameter of the organic particles is not particularly limited, and may be, for example, 0.1 to 10 μm, preferably 0.3 to 5 μm. Within this range, the organic particles can be appropriately dispersed without interfering with the conductivity of the conductive particles.

The organic particles may be present in an amount of from 1 to 10% by weight based on the total weight of the anisotropic conductive film composition. If the content of the organic particles is less than 1% by weight, the organic particles hardly have any effect. If the content is more than 10% by weight, the viscosity of the film is reduced, resulting in deterioration of the preliminary pressing property.

In one embodiment, organic particles comprising a copolymer of methyl methacrylate, styrene and divinylbenzene or a copolymer of methyl methacrylate, styrene and butadiene may be used.

Free radical polymerization initiator

The radical initiator is another component of the curing system of the anisotropic conductive film, and may include at least a photocurable initiator and a heat curable initiator One.

Examples of such photocurable initiators include benzophenone, methyl o-benzimidylbenzoate, 4-benzylidene-4-methyldiphenyl sulfide, isopropylthioxanthone , diethyl thioxanthone, ethyl 4-diethylbenzoate, benzoin ether, benzoin propyl ether, 2-hydroxy-2-methyl-1-phenylpropan-1-one, and diethoxy B Benzene, but not limited to this.

The heat curable initiator can include, without limitation, a peroxide and an azo initiator. Examples of the peroxide initiator include lauryl peroxide, benzammonium peroxide, and cumene hydroperoxide, but are not limited thereto. Examples of the azo starter include 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile), dimethyl-2,2'-azobis (2-A) Propionate), and 2,2'-azo (N-cyclohexyl-2-methyl-propanamide), but is not limited thereto.

The radical polymerization initiator may be present in an amount of from 0.5 to 5% by weight, preferably from 1 to 4% by weight, based on the total mass of the anisotropic conductive film composition.

Conductive particles

The conductive particles serve as a reinforcing agent for imparting conductivity to the composition of the anisotropic conductive film. The conductive particles may comprise metal particles (including Au, Ag, Ni, Cu, Pb, and solder particles); carbon particles; metal coated resin particles (including coatings coated with Au, Ag, Ni, Cu, Pb, and solder) At least one of ethylene, polypropylene, polyester, polystyrene, polyvinyl alcohol, and particles of the modified resin thereof; and further conductive particles coated with insulating particles.

The size of the conductive particles is not particularly limited, but may be larger than the diameter of the polyurethane beads. Therefore, the stability of the electrical characteristics and good connection reliability can be achieved to make. For example, the conductive particles may have a diameter of 1 to 20 μm, preferably 1 to 8 μm.

The conductive particles may be present in an amount of from 1 to 10% by weight based on the total amount of the anisotropic conductive film composition in terms of solid content. Within this range, the electrical properties of the stability can be exhibited without short circuits. Preferably, this amount may be from 1 to 5% by weight.

The anisotropic conductive film composition of the present invention may further contain an additive such as a polymerization inhibitor, an antioxidant, a heat stabilizer, or the like to provide additional properties without impeding the basic properties. The additive may be present in an amount of from 0.01 to 10% by weight based on the solid content, based on the amount of the anisotropic conductive film, but is not limited thereto.

The polymerization inhibitor may be selected from hydroquinone, hydroquinone monomethyl ether, p-benzoquinone, phenolthiophene. And the ethnic group formed by a mixture of them. The antioxidant may include a phenol or a hydroxycinnamate compound, for example, tetra-[methyl(3,5-di-t-butyl-4-hydroxycinnamate)]methane, and 3,5-bis-(1, 1-Dimethylethyl)-4-hydroxypropanol sulfur-di-2,1-ethanediester.

Another aspect of the present invention provides an anisotropic conductive film formed from the anisotropic conductive film composition. The formation of such an anisotropic conductive film system does not require special equipment or equipment. For example, the anisotropic conductive film can be stirred and liquefied in an organic solvent (for example, toluene) by stirring the solution, and the solution is stirred at a rate at which the conductive particles are not pulverized for a certain period of time. It is obtained by applying a release film to a suitable thickness (for example, 10 to 50 μm), and drying the solution to volatilize toluene.

Another aspect of the present invention provides a semiconductor device comprising: a wiring substrate; an anisotropic conductive film attached to one of the wiring substrate mounting side; and a semiconductor wafer mounted on the anisotropic conductive film, wherein the anisotropic conductive film Films The films or systems described herein are formed from the compositions described herein.

Next, the present invention will be described in detail with reference to the following examples, comparative examples, and experimental examples. However, it is to be understood that the examples are provided for illustration only and are not to be construed as limiting the scope of the embodiments.

Details that are apparent to those skilled in the art will be omitted herein.

Examples 1 to 5: Preparation of an anisotropic conductive film

A urethane resin, an EVA copolymer, a tricyclodecane dimethanol diacrylate, organic particles, an organic peroxide, conductive particles, and a toluene as a solvent are added to a planetary mixture according to the composition listed in Table 1. Dissolving and dispersing, after which the solution is applied to a PET film treated with a release agent, and the solvent is volatilized by heating in a forced convection oven heated to 60 ° C for 5 minutes, thereby obtaining 35 μm. An anisotropic conductive film of thickness.

Comparative Examples 1 and 2: Preparation of an anisotropic conductive film

The anisotropic conductive film was fabricated in the same manner as in Examples 1 to 5, but the composition was changed as shown in Table 1.

The details of the compositions used in Examples 1 to 5 and Comparative Examples 1 and 2 are shown in Table 1.

(1) Urethane resin

60% by weight of polyol (polytetramethyl glycol), 13.53% by weight of 1,4-butanediol, 26.14% by weight of toluene diisocyanate, 0.3% by weight of hydroxyethyl methacrylate, and 0.03 % by weight of dibutyltin dilaurate as a catalyst. First, a polyol, 1,4-butanediol, and toluene diisocyanate are reacted to synthesize a prepolymer having an isocyanate terminal. Then, the prepolymer having an isocyanate terminal and hydroxyethyl methacrylate are reacted to produce a urethane acrylate resin. Here, the additional polymerization is carried out by using a molar ratio of hydroxyethyl methacrylate to the isocyanate of the prepolymer terminal of 0.5, a temperature of 90 ° C and 1 atm, using dibutyltin dilaurate as a catalyst for 5 hours. Thereby, a urethane acrylate having a weight average molecular weight of 25,000 was produced.

(2) EVA copolymer

80 grams of EVA copolymer containing 33% vinyl acetate dissolved in 2:1 Within a mixture of benzyl ethyl ketone, a solution having a solids content of 35% (Evaflex EV 180, Mitsui-Dupont Polychemical Co.) was prepared therefrom.

(3) Radical polymerizable material 1: Tricyclodecane dimethanol diacrylate (TCDDMA, KARAYAD R-584, Nippon Kayaku Co., Ltd.).

(4) Radical polymerizable material 2: epoxy acrylate polymer (SP1509, Showa Highpolymer Co., Ltd.).

(5) Organic particles: methyl methacrylate / styrene / divinyl benzene copolymer

100 ml of acetonitrile as a solvent was placed in a three-necked round bottom flask equipped with a condenser in a nitrogen atmosphere, and methyl methacrylate, styrene monomer, and divinylbenzene were compared with the solvent. Fixed at 2% by weight. Here, the divinylbenzene as a crosslinking agent is added at a concentration of 50% by weight based on the concentration of the styrene monomer. The flask holding this mixture was maintained at 70 °C. 0.04 g of 2,2'-azobisisobutyronitrile as a starter was added to the mixture, followed by precipitation polymerization for 24 hours, and stirring at 30 rpm, thereby producing a polystyrene divinylbenzene copolymer having Average diameter of 3 to 4 μm.

(6) Organic peroxide: Benzoyl peroxide (Hansol Chemical)

(7) Conductive particles: conductive particles (Ni) having a size of 3 to 5 μm

The adhesive films prepared in Examples 1 to 5 and Comparative Examples 1 and 2 were tested as follows, and the results are shown in Table 2.

1. Measure connection resistance and adhesion

To evaluate anisotropic conductive films according to Examples 1 to 5 and Comparative Examples 1 and 2 For each of the bonding defects and adhesion, each film is attached to a PCB under the following conditions (pitch: 200 μm, terminal: 100 μm, distance between terminals: 100 μm, terminal height: 35 μm) and COF (pitch: 200 μm, terminal: 100 μm, distance between terminals: 100 μm, terminal height: 8 μm):

1) Initial pressing: 70 ° C, 1 second, 1.0 MPa

2) Final pressing: 150 ° C, 4 seconds, 4.0 MPa (condition 1), 200 ° C, 4 seconds, 4.0 MPa (condition 2)

Five samples were prepared for each membrane system and the adhesion was evaluated via the sample system of Condition 1.

2. Measuring elongation

To measure the elongation, the samples were prepared as follows. Each 35 μm thick anisotropic conductive film was placed on a hot press, and a 0.2 mm thick silicone resin was placed thereon, followed by heating/pressing at 190 ° C and 30 MPa for 15 minutes to cure. The material being connected. Then, after the release film was removed, the anisotropic conductive film was cut into pieces of 2.0 mm width and 30 mm length for use.

The tensile test was performed using a universal test machine (UTM), and the H5KT type (Hounsfield) was carried out as follows.

After installing a 5N load cell (adhesion: 100 N), the jig was mounted, and then the sample was fixed with a jig and the elongation was measured at a tensile test speed of 50 mm/min.

X: not connectable

The adhesive compositions according to Examples 1 to 5 exhibited satisfactory connection resistance, elongation, and adhesion, and the composition according to Comparative Example 1 had reduced fluidity due to lack of EVA copolymer, and defects in connection resistance . The composition according to Comparative Example 2 did not have the effect of relieving stress due to the lack of organic particles, resulting in a significant increase in elongation. Further, the composition according to Comparative Example 2 contained partial separation during high-temperature pressing, resulting in defects in connection resistance.

While the invention has been described by the foregoing embodiments, the embodiments of the invention are The spirit and scope of the present invention are carried out. The scope of the invention should be limited only by the scope of the accompanying claims.

Claims (19)

An anisotropic conductive adhesive film having an elongation of 10 to 100% after curing, and comprising: a binder resin in a solid content of 40 to 80% by weight based on the total weight of the film, the bonding The resin comprises a polyester urethane resin, a urethane acrylate resin, and at least one of the polyester urethane resin and the urethane resin of the urethane acrylate resin; and organic particles. The anisotropic conductive adhesive film according to claim 1, wherein the anisotropic conductive adhesive film has a preliminary pressing at 70 ° C and 1.0 MPa for 1 second and a final pressing at 150 ° C and 4.0 MPa for 4 seconds. Bonding strength of 800gf/cm or higher. An anisotropic conductive adhesive film according to claim 1 or 2, wherein the anisotropic conductive adhesive film exhibits an increase in connection resistance of more than 0 and 40% or less when calculated by Equation 1: connection resistance Increase (%)=(AB)/A×100 (Equation 1) where A is initially pressed at 70 ° C and 1.0 MPa for 1 second and is finally pressed at 150 ° C and 4.0 MPa for 4 seconds, and B is the connection resistance. Initial compression, the final compression, and subsequent connection resistance after 500 hours of testing at 85 ° C and 85% RH reliability. An anisotropic conductive adhesive film according to claim 1 or 2, wherein the organic particles are present in an amount of from 1 to 10% by weight based on the total weight of the film. An anisotropic conductive adhesive film as claimed in claim 1 or 2, The organic particles have a single layer structure or a multilayer structure. An anisotropic conductive adhesive film according to claim 5, wherein the organic particles having the single layer structure comprise polyurethane particles. The anisotropic conductive adhesive film of claim 6, wherein the polyurethane particles have an ion content of more than 0 and 10 ppm or less. The anisotropic conductive adhesive film of claim 5, wherein the organic particles having the multilayer structure have a two-layer structure comprising a core and a shell, wherein a polymer of the core is formed The resin has a lower glass transition temperature than the polymer resin forming one of the shells. An anisotropic conductive adhesive film according to claim 1 or 2, wherein the organic particles comprise a copolymer of methyl methacrylate, styrene and divinylbenzene, or comprise methyl methacrylate, a copolymer of styrene and butadiene. An anisotropic conductive film composition comprising: a binder comprising a polyester urethane resin, a urethane acrylate resin, and a urethane resin which is not the polyester urethane resin and the urethane acrylate resin At least one; an ethylene-vinyl acetate copolymer; a radical polymerizable material comprising tricyclodecane dimethanol diacrylate, or tricyclodecane dimethanol dimethacrylate; and organic particles. The anisotropic conductive film composition of claim 10, wherein the anisotropic conductive film composition contains 40 to 80% by weight of the binder based on the total weight of the composition. , 5 to 30 The ethylene-vinyl acetate copolymer, 10 to 40% by weight of the radically polymerizable material, and 1 to 10% by weight of the organic particles. The anisotropic conductive film composition of claim 10, wherein the ethylene-vinyl acetate copolymer comprises 15 to 35 wt% of vinyl acetate. The anisotropic conductive film composition of claim 10, wherein the organic particles have a single layer structure or a multilayer structure. The anisotropic conductive film composition of claim 13, wherein the organic particles having the single layer structure comprise polyurethane particles. The anisotropic conductive film composition of claim 14, wherein the polyurethane particles have an ion content of more than 0 and 10 ppm or less. The anisotropic conductive film composition of claim 13, wherein the organic particles having the multilayer structure have a two-layer structure comprising a core and a shell, wherein a polymer of the core is formed The resin has a lower glass transition temperature than the polymer resin forming one of the shells. The anisotropic conductive film composition of claim 10, wherein the organic particles comprise a copolymer of methyl methacrylate, styrene and divinylbenzene, or comprise methyl methacrylate or styrene. And a copolymer of butadiene. The anisotropic conductive film composition of claim 10, further comprising a radical polymerization initiator, and conductive particles. A semiconductor device comprising: a wiring substrate; An anisotropic conductive film attached to one side of the mounting substrate of the wiring substrate; and a semiconductor wafer mounted on the anisotropic conductive film, wherein the anisotropic conductive film is patented A film formed by the film of any one of the items 1 to 9 or the film of any one of claims 10 to 18.