KR101893248B1 - Anisotropic conductive film and a connecting structure using thereof - Google Patents

Abstract

An embodiment of the present invention is an anisotropic conductive film comprising a conductive layer and an insulating layer, wherein each of the conductive layer and the insulating layer includes two kinds of inorganic fillers having different particle diameters, 1 to 3 seconds and a pressure of 1.0 MPa to 3.0 MPa and compression bonding at 120 to 160 DEG C for 3 to 6 seconds under pressure conditions of 60 to 90 MPa, Wherein the insulating layer is a conductive layer and has a curing rate of 90% or more and a storage modulus when cured of 2.5 to 5 GPa.
[Formula 1]
(%) = [(Length in the width direction of the layer after compression-length in the width direction of the layer before compression) / length in the width direction of the layer before compression] × 100
The anisotropic conductive film according to one embodiment of the present invention has an advantage of improving the insulating property and the connection reliability by increasing the dispersibility of the conductive particles.

Description

TECHNICAL FIELD [0001] The present invention relates to an anisotropic conductive film and a connection structure using the anisotropic conductive film.

The present invention relates to an anisotropic conductive film and a connection structure using the same.

Anisotropic conductive film (ACF) generally refers to a film-like adhesive in which conductive particles are dispersed in a resin such as an epoxy resin. An anisotropic conductive film (ACF) is a film-like adhesive in which conductive particles are dispersed in a resin such as epoxy, Means a polymer membrane having anisotropy and adhesion. When the film is placed between the circuit to be connected with the anisotropic conductive film and subjected to a heating and pressing process under a certain condition, the circuit terminals are electrically connected by the conductive particles, and an insulating adhesive resin And the conductive particles are filled independently of each other, thereby giving high insulating properties.

In the conventional two-layer structure anisotropic conductive film, a composition flow including conductive particles is generated due to heat and pressure in the process of connecting the terminals to each other through the hot pressing process, so that the particle efficiency for expressing connection characteristics between terminals is extremely low , A part of the composition containing the conductive particles flows into the adjacent space (space portion), and the conductive particles collect in a narrow area, resulting in a short circuit or a large connection resistance.

Therefore, it is necessary to develop an anisotropic conductive film which prevents short-circuit between the electrodes and is excellent in connection characteristics while sufficiently filling the insulating adhesive resin between the electrodes.

An object of the present invention is to provide an anisotropic conductive film excellent in insulation and connection reliability by increasing the dispersibility of conductive particles.

In one embodiment of the present invention, an anisotropic conductive film comprising a conductive layer and an insulating layer and including two kinds of inorganic fillers having different particle diameters, wherein the film is heated at a temperature of 50 to 80 DEG C for 1 to 3 seconds, And the rate of increase of the spreading length as measured by the following formula 1 measured after compression bonding at 120 to 160 DEG C for 3 to 6 seconds under a pressure of 60 to 90 MPa is the insulating layer> There is provided an anisotropic conductive film having a curing rate of 90% or more and a storage elastic modulus during curing of 2.5 to 5 GPa.

[Formula 1]

(%) = [(Length in the width direction of the layer after compression-length in the width direction of the layer before compression) / length in the width direction of the layer before compression] × 100

In another embodiment of the present invention, a first connected member containing a first electrode; A second connected member containing a second electrode; And a connecting structure connected by the anisotropic conductive film described herein, which is located between the first connected member and the second connected member and connects the first electrode and the second electrode.

The anisotropic conductive film according to one embodiment of the present invention has an advantage of improving the insulating property and the connection reliability by increasing the dispersibility of the conductive particles.

1 shows a first embodiment of the present invention in which a first connected member 50 including a first electrode 70, a second connected member 60 including a second electrode 80, A connection structure according to an embodiment of the present invention, comprising an anisotropic conductive film (10) as described herein, which is located between two connected members and connects the first electrode and the second electrode via conductive particles (3) Fig.

Hereinafter, the present invention will be described in more detail. Those skilled in the art will appreciate that various modifications, additions, and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

An embodiment of the present invention is an anisotropic conductive film comprising a conductive layer and an insulating layer and including two types of inorganic fillers having different particle diameters, wherein the film is heated at a temperature of 50 캜 to 80 캜 for 1 to 3 seconds, And the rate of increase of the spreading length as measured by the following formula 1 measured after compression bonding at 120 to 160 DEG C for 3 to 6 seconds under a pressure of 60 to 90 MPa is the insulating layer> And a storage elastic modulus of 2.5 to 5 GPa when cured at a curing rate of 90% or more.

[Formula 1]

(%) = [(Length in the width direction of the layer after compression-length in the width direction of the layer before compression) / length in the width direction of the layer before compression] × 100

When the rate of increase of the spreading length of the insulating layer is larger than the rate of increase of the spreading length of the conductive layer, it means that the fluidity of the insulating layer is larger than that of the conductive layer. In this case, There is an advantage that flow of the conductive particles to the space portion can be reduced by the low fluidity of the conductive layer, and short-circuiting can be prevented.

The increase rate of the spreading length of the insulating layer may be 60 to 120%, specifically 70 to 115%, and more specifically 75 to 110%.

In addition, the rate of increase of the spreading length of the conductive layer may be 10 to 60%, specifically 20 to 50%, and more specifically 25 to 45%.

There is an advantage that the insulating layer can be evenly filled within the range of increasing the spreading length of each layer and the connection reliability of the anisotropic conductive film can be improved.

In one embodiment, the difference between the rate of increase of the spreading length of the conductive layer and the rate of increase of the spreading length of the insulating layer may be 40 to 80%, and more specifically, 40 to 60%. The insulating property and the connection reliability characteristics of the anisotropic conductive film can be further improved within the difference in the rate of increase of the spreading length of the conductive layer and the insulating layer.

A sample of 2 mm in the width direction x 20 mm in the longitudinal direction was prepared, and the glass substrate was placed at the top and bottom of the anisotropic conductive film, and then the substrate was heated at 70 DEG C for 1 second and 1.0 MPa, and compression bonded at 150 DEG C for 5 seconds and under a pressure of 80 MPa. At this time, the length in the width direction of the layer after compression of the layer in the width direction before compression is measured, and it can be expressed as an increase rate (%) of the spreading length according to Expression 1 with respect to the increased length.

The anisotropically conductive film may have a curing rate of 90% or more and a storage elastic modulus when cured of 2.5 to 5 GPa. Specifically from 3 to 5 GPa, and more specifically from 3.5 to 4.5 GPa. When the cure has progressed by more than 90%, it usually means when the cure is complete.

When the storage elastic modulus of the anisotropic conductive film is in the above range, it is possible to have the desired viscosity without interfering with the fluidity of the insulating layer, thereby increasing the morphological stability of the film and preventing short-circuit between the terminals.

The method of measuring the storage elastic modulus is not particularly limited and a method commonly used in the art can be used. As a non-limiting example of the method of measuring the storage elastic modulus, an anisotropic conductive film is allowed to stand in a hot air oven at 150 DEG C for 2 hours, and the storage elastic modulus at 40 DEG C is measured using DMA (Dynamic Mechanical Analyzer; can do.

The anisotropic conductive film according to an embodiment of the present invention may have a multilayer structure including a conductive layer and an insulating layer. Specifically, it may be an anisotropic conductive film having a multilayer structure in which an insulating layer is laminated on a conductive layer.

The term " lamination " means that another layer is formed on one side of an arbitrary layer and can be used in combination with coating or lamination. In the case of an anisotropic conductive film having a two-layer structure including a conductive layer and an insulating layer, since the layer is separated, there is an advantage that an anisotropic conductive film having appropriate fluidity can be produced without interfering with the pressing of the conductive particles.

The anisotropic conductive film may include two kinds of inorganic fillers having different particle diameters. By including the two types of inorganic fillers having different particle diameters, dispersibility of the conductive particles can be improved, shorting can be prevented, connection characteristics can be improved, and film formability can be improved.

The inorganic filler is not particularly limited, and inorganic fillers conventionally used in the art can be used. Non-limiting examples of the inorganic filler include alumina, silica, titania, zirconia, magnesia, ceria, zinc oxide, iron oxide, silicon nitride, titanium nitride, boron nitride, calcium carbonate, aluminum sulfate, aluminum hydroxide, calcium titanate, talc, calcium silicate , Magnesium silicate, and the like. Specifically, alumina, silica, calcium carbonate or aluminum hydroxide can be used, and in one example, alumina or silica can be used.

The inorganic filler may be surface-treated with a compound such as a phenylamino group, a phenyl group, a methacrylic group, a vinyl group or an epoxy group to improve the dispersibility in the anisotropic conductive film.

The method of surface-treating the inorganic filler is not particularly limited. As an example of the surface treatment method, a surface treatment material is directly mixed with an inorganic filler using a Henschel mixer, and if necessary, the surface treatment is performed by a dry method such as heat treatment . The surface treatment agent may be diluted in a suitable solvent and used.

The two kinds of inorganic fillers may be included in any one of the conductive layer and the insulating layer. One of them may be contained in each of the conductive layer and the insulating layer, and two kinds of inorganic The filler may be included at the same time. Specifically, both of the conductive layer and the insulating layer may contain two kinds of inorganic fillers at the same time.

The two kinds of inorganic fillers may be contained in an amount of 20 to 80% by weight, specifically 30 to 70% by weight, more specifically 35 to 65% by weight, based on the total weight of the anisotropic conductive film. The conductive particles can be effectively dispersed within the above range and the fluidity of the anisotropic conductive film can be appropriately controlled.

When two kinds of inorganic fillers are simultaneously contained in both the conductive layer and the insulating layer according to an embodiment, the two kinds of inorganic fillers are contained in an amount of 20 to 50% by weight, specifically 20 to 40% by weight, And may be contained in an amount of 30 to 80% by weight, specifically 40 to 70% by weight, based on the total weight of the insulating layer.

In one embodiment, the two kinds of inorganic fillers may include a first inorganic filler having a particle diameter of 1 to 40 nm and a second inorganic filler having a particle diameter of 50 to 1,000 nm.

The first inorganic filler having a particle diameter of 1 to 40 nm has an effect that the surface tension of the anisotropic conductive film is lowered, the coating is generally well performed, the lifting phenomenon after curing is prevented, and the film formability is improved. The first inorganic filler may specifically have a particle diameter ranging from 1 to 30 nm, more specifically ranging from 1 to 10 nm.

The second inorganic filler having a particle diameter of 50 to 1,000 nm is located between the conductive particles to improve the dispersibility of the conductive particles, improve the storage elastic modulus, increase the particle capture rate, . The second inorganic filler may have a particle diameter ranging from 50 to 800 nm, more specifically, from 50 to 500 nm.

The weight ratio of the first inorganic filler to the second inorganic filler may be 1: 2 to 1:10, and may be 1: 2 to 1: 8, more specifically, 1: 3 to 1: 5. Within this range, the anisotropic conductive film may have appropriate fluidity and viscosity, good particle capture rate, and film formability can be improved.

In one embodiment, the conductive layer of the anisotropic conductive film may further include a binder resin, an epoxy resin, a curing agent, and conductive particles.

Examples of the binder resin include polyimide resin, polyamide resin, phenoxy resin, polymethacrylate resin, polyacrylate resin, polyurethane resin, polyester resin, polyester urethane resin, polyvinyl butyral resin, styrene- Butadiene rubber (NBR) and its hydrogenated product, or a combination thereof, and a styrene-butylene-styrene (SBS) resin and an epoxy modified product, a styrene- . Specifically, a phenoxy resin can be used as the binder resin, and more specifically, a fluorene-based phenoxy resin can be used. The fluorene-based phenoxy resin can be used without limitation as long as it is a phenoxy resin containing a fluorene structure.

The binder resin may include 10 to 40% by weight based on the total weight of the anisotropic conductive film. Specifically 10 to 30% by weight.

Examples of the epoxy resin include bisphenol type epoxy resins such as bisphenol A type epoxy resin, bisphenol A type epoxy acrylate resin, bisphenol F type epoxy resin, bisphenol AD type epoxy resin, bisphenol E type epoxy resin and bisphenol S type epoxy resin; Aromatic epoxy resins such as polyglycidyl ether epoxy resin, polyglycidyl ester epoxy resin and naphthalene epoxy resin; Alicyclic epoxy resins; Novolak type epoxy resins such as cresol novolak type epoxy resin and phenol novolak type epoxy resin; Glycidylamine type epoxy resin; Glycidyl ester-based epoxy resin; Biphenyl diglycidyl ether epoxy resin, and the like. These may be used alone or in combination of two or more. Specifically, an alicyclic epoxy resin can be used. The alicyclic epoxy resin is close to the alicyclic ring and has an epoxy structure. Therefore, the ring opening reaction is fast and the curing reaction is better than other epoxy resins. The alicyclic epoxy resin may be used without limitation as long as it has a structure in which a direct bond is bonded to an alicyclic ring or an epoxy structure exists through another linking group.

The epoxy resin may be contained in an amount of 10 to 40% by weight based on the total weight of the anisotropic conductive film, specifically 10 to 35% by weight, more specifically 15 to 30% by weight.

The weight ratio of the binder resin to the epoxy resin may range from 4: 6 to 6: 4. It is possible to obtain a stable effect of connection performance after thermocompression in manufacturing within the above weight ratio range. Specifically, the weight ratio may range from 4: 6 to 5: 5.

The curing agent can be used without particular limitation as far as it can cure the epoxy resin to form an anisotropic conductive film. As the non-limiting examples of the curing agent, an acid anhydride type, amine type, imidazole type, isocyanate type, amide type, hydrazide type, phenol type, cation type and the like can be used. Specifically, the curing agent may be a cationic curing agent or an amine curing agent. The cationic curing agent has an advantage that the reaction can be performed very rapidly, and the amine curing agent is advantageous in terms of stability and has an advantage that the content of the stabilizer can be reduced to a small extent. In one embodiment, the curing agent may be a sulfonium curing agent.

The curing agent may be contained in an amount of 1 to 10% by weight based on the total solid weight of the anisotropic conductive film, and may be contained in an amount of 1 to 5% by weight. Within the above range, a sufficient reaction required for curing takes place, and excellent physical properties can be expected in adhesion strength, reliability, etc. after bonding through formation of an appropriate molecular weight.

The conductive particles are not particularly limited and conductive particles conventionally used in the art can be used. Non-limiting examples of the conductive particles include metal particles including Au, Ag, Ni, Cu, solder, and the like; carbon; Particles comprising a resin including polyethylene, polypropylene, polyester, polystyrene, polyvinyl alcohol or the like and particles of the modified resin coated with a metal such as Au, Ag, Ni or the like; Insulating particles coated with insulating particles, and the like. The size of the conductive particles may be in the range of, for example, 1 탆 to 20 탆, specifically 1 탆 to 10 탆, depending on the pitch of the applied circuit.

The conductive particles may be contained in an amount of 1 to 50% by weight based on the total weight of the anisotropic conductive film, and specifically 10 to 35% by weight. In this range, the conductive particles can be easily pressed between the terminals to ensure stable connection reliability, and the connection resistance can be reduced by improving the electrical conductivity.

In one embodiment, the anisotropic conductive film may further comprise a silane coupling agent in addition to the above components.

Examples of the silane coupling agent include polymerizable fluorinated group-containing silicon compounds such as vinyltrimethoxysilane, vinyltriethoxysilane and (meth) acryloxypropyltrimethoxysilane; Silicon compounds having an epoxy structure such as 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, and 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane; Containing silicon compounds such as 3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane and N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane. ; And 3-chloropropyltrimethoxysilane, and the like, but are not limited thereto.

The silane coupling agent may be contained in an amount of 1 to 10% by weight based on the total weight of the anisotropic conductive film.

In another embodiment, the anisotropic conductive film may further include an additive such as a polymerization inhibitor, an antioxidant, a heat stabilizer, etc. to provide additional physical properties without impairing the basic physical properties. The additive is not particularly limited, but may be included in an amount of 0.01 to 10% by weight based on the total weight of the anisotropic conductive film.

Examples of the polymerization inhibitor include hydroquinone, hydroquinone monomethyl ether, p-benzoquinone, phenothiazine, or a mixture thereof. As the antioxidant, a phenolic or hydroxycinnamate-based material can be used. For example, tetrakis- (methylene- (3,5-di-t-butyl-4-hydoxinnamate) methane, 3,5-bis (1,1-dimethylethyl) -4- -2,1-ethanediyl ester and the like can be used.

The insulating layer may include other components than conductive particles among components that may be further included in the conductive layer. The respective components are as described above.

The anisotropically conductive film is pressure bonded at a temperature of 50 to 80 DEG C for 1 to 3 seconds and at a pressure of 1.0 to 3.0 MPa and compression bonded at 120 to 160 DEG C for 3 to 6 seconds under pressure conditions of 60 to 90 MPa The particle capture rate measured according to the following formula 2 may be 20 to 60%. Specifically, it may be from 25 to 55%, and more specifically from 30 to 50%.

[Formula 2]

(Mm ² ) number of conductive particles per unit area (mm ² ) of anisotropically conductive film before compression bonding (%) = (number of conductive particles per unit area (mm ² )

The fluidity of the conductive layer is effectively suppressed within the above range, the conductive particles are sufficiently located on the terminal, the conductivity is improved, and the outflow of the conductive particles is reduced to reduce the short-circuit between the terminals.

The method for measuring the particle capture rate is not particularly limited, and a non-limiting example is as follows. For the prepared anisotropic conductive film, the number of conductive particles (mm ² ) per unit area of the anisotropic conductive film before compression Calculated using an automatic meter. Then, an anisotropic conductive film 1,200㎛ bump area ^2, placed on a glass substrate with indium tin oxide having a thickness of 2,000Å circuit 70 ℃, and then pressed in a good condition of 1MPa and 1 seconds, remove the release film and the bump area 1,200㎛ ² , An IC chip having a thickness of 1.5T was placed thereon, and the IC chip was pressed at 150 DEG C for 5 seconds under a condition of 80 MPa. The number of conductive particles per unit area (mm ² ) of the connection site was calculated using a particle automatic meter, To calculate the particle capture rate.

The anisotropic conductive film may have a minimum melt viscosity at 50 ° C to 100 ° C of 1,000 to 100,000 Pa · s. Specifically 10,000 to 100,000 Pa · s. Within this range, the anisotropic conductive film exhibits appropriate fluidity, so that the coverage of the conductive particles can be improved.

The method of measuring the lowest melt viscosity is not particularly limited and examples are as follows. Nonlimiting examples are as follows: Using a ARES G2 rheometer (TA Instruments), a sample having a thickness of 150 탆, a temperature rising rate of 10 캜 / ) 5%, and the angular frequency is 1.0 rad / sec. The minimum melt viscosity of the anisotropic conductive film is measured in the range of 0 ° C to 250 ° C.

The anisotropic conductive film may have a melt viscosity variation of 0 to 0.2, preferably 0 to 0.17, expressed by the following formula (3).

 [Formula 3]

(Melt viscosity of the film at 75 DEG C - Melt viscosity of the film at 55 DEG C) / (75 DEG C - 55 DEG C)

When the range of the melt viscosity variation is satisfied, the lowest melt viscosity is maintained at a constant temperature range, so that the fluidity of the composition is excellent and the indentation can be improved.

The anisotropic conductive film is press-bonded under the conditions of 50 to 80 DEG C for 1 to 3 seconds and 1.0 to 3.0 MPa and compression bonded at 120 to 160 DEG C for 3 to 6 seconds under pressure conditions of 60 to 90 MPa The connection resistance can be 5 Ω or less after the reliability test as measured by keeping the temperature at 85 ° C. and 85% relative humidity for 500 hours. Specifically, it can be 3Ω or less, more specifically, 2Ω or less.

The anisotropic conductive film having a connection resistance range after the reliability evaluation can not only improve the connection reliability but also has an advantage that it can be used for maintaining long-term stability.

A method for measuring the connection resistance after the reliability evaluation is not particularly limited, and a non-limiting example is as follows: An anisotropic conductive film is placed on a glass substrate having an indium tin oxide circuit with a bump area of 1200 탆 ² and a thickness of 2,000 Å, C. for 1 second and 1 MPa, and then the release film was removed. IC chips having a bump area of 1200 .mu.m ² and a thickness of 1.5T were placed thereon. The IC chips were then compression-bonded at 150.degree. C. for 5 seconds under a pressure of 80 MPa The resistance between the four points is measured using a resistance measuring instrument (2000 Multimeter, Keithley) using the 4 point probe method and expressed as an initial connection resistance. Thereafter, the test piece thus prepared was allowed to stand for 500 hours at a temperature of 85 ° C and a relative humidity of 85%, and the resistance was measured in the same manner. The resistance measuring device applies 1mA, and the resistance is calculated by the measured voltage and averaged.

The anisotropic conductive film is press-bonded under the conditions of 50 to 80 DEG C for 1 to 3 seconds and 1.0 to 3.0 MPa, and compression bonded at 120 to 160 DEG C for 1 to 5 seconds under pressure conditions of 60 to 90 MPa An initial shot incidence may be 0%.

The anisotropic conductive film having the initial shot incidence rate range can reduce the driving voltage of the circuit.

The method of measuring the initial shot incidence rate is not particularly limited, and a non-limiting example is as follows: Anisotropic conductive film is cut into 2 mm x 25 mm, bonded to each of the insulation resistance evaluation materials and evaluated. In other words. The anisotropic conductive film is placed on a glass substrate having a thickness of 0.5 mm and heated / pressed under the conditions of 70 DEG C, 1 MPa, and 1 sec to remove the release film. Thereafter, a chip (chip length 19.5 mm, chip width 1.5 mm, bump spacing 8 탆) is placed on the anisotropic conductive film, and finally compression bonded at 150 캜, 70 MPa, and 1 sec to manufacture a circuit device. Thereafter, 50 V is applied and the occurrence of a short is checked at a total of 38 points by the two-terminal method, and an initial shot incidence is measured.

The anisotropic conductive film is press-bonded under the conditions of 50 ° C to 80 ° C for 1 to 3 seconds and 1.0 MPa to 3.0 MPa and compression bonded at 120 ° C to 160 ° C for 1 to 5 seconds under pressure conditions of 60 MPa to 90 MPa, The reliability shot occurrence rate measured by leaving it at 500 캜 under the conditions of a temperature of 85 캜 and a relative humidity of 85% may be 0%.

The anisotropic conductive film having the reliability shot generation rate range can keep the drive voltage of the circuit low continuously, thereby enabling long-term stability to be maintained.

The method for measuring the reliability shot occurrence rate is not particularly limited, and a non-limiting example is as follows. The circuit apparatus used for the measurement of the initial shot occurrence rate is left for 500 hours at a temperature of 85 캜 and a relative humidity of 85% The reliability shot generation rate is measured in the same manner as in the method in which the initial shot occurrence rate is measured.

In one embodiment, the anisotropic conductive film may be used in a COG (chip on glass) or COF (chip on film) mounting method.

Hereinafter, a method of manufacturing an anisotropic conductive film according to another embodiment of the present invention will be described.

No special apparatus or equipment is required to form the anisotropic conductive film of the present invention. For example, an anisotropic conductive film composition containing the respective compositions disclosed herein is dissolved in an organic solvent such as toluene and liquefied. Thereafter, the conductive particles are agitated for a predetermined time in a range in which the conductive particles are not pulverized, For example, to a thickness of 5 to 50 탆, and then dried for a predetermined time to volatilize toluene or the like to obtain an anisotropic conductive film.

Hereinafter, a connection structure according to another embodiment of the present invention will be described.

The connection structure comprising: a first connected member containing a first electrode; A second connected member containing a second electrode; And a connection structure connected by the anisotropic conductive film according to the embodiments described herein, which is located between the first connected member and the second connected member and connects the first electrode and the second electrode. .

Specifically, the first to-be-connected members or the second to-be-connected members are formed of ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), or the like used for a liquid crystal display A printed wiring board, a ceramic wiring board, a flexible wiring board, a semiconductor silicon chip, an IC chip, or a driver IC chip on which electrodes of the first to-be-connected members and the electrodes to be connected are formed. More specifically, May be an IC chip or a driver IC chip, and the other may be a glass substrate.

The first connecting member 50 including the first electrode 70 and the second connected member 60 including the second electrode 80 will be described with reference to Fig. Through the anisotropic conductive film (10) comprising the conductive particles (3) described herein, which is located between the first connected member and the second connected member and connects the first electrode and the second electrode They can be bonded to each other.

Hereinafter, the configuration and operation of the present invention will be described in more detail with reference to preferred embodiments of the present invention. It is to be understood, however, that the same is by way of illustration and example only and is not to be construed in a limiting sense.

The contents not described here are sufficiently technically inferior to those skilled in the art, and a description thereof will be omitted.

Example

Example 1

1. Fabrication of conductive layer

20% by weight of biphenyl fluorene type binder resin (FX-293, Shinil Chemical Co., Tg: 165 캜, molecular weight: 45,000), 10% by weight of epoxy resin 1 (Celloxide 2021P, DAICEL), epoxy resin 2 (YDPN 638, (KSFD, average particle size 3.0 탆, NCI), silica (R812, Tokuyama corporation) 3 weight having a particle diameter of 7 nm as a first inorganic filler (weight: 5 wt%), a cationic curing agent (SI-B3A, And 20% by weight of silica having a particle size of 50 nm (YA050C, Admatech) surface-treated with phenylamino as a second inorganic filler were mixed to prepare a conductive layer composition. The conductive layer composition was coated on a release film, and then the solvent was evaporated in a drier at 70 캜 for 5 minutes to obtain a dried conductive layer having a thickness of 6 탆.

2. Fabrication of insulation layer

In the production of the conductive layer, a dry insulating layer having a thickness of 12 탆 was formed under the same conditions and in the same manner as in the production of the conductive layer, except that the contents of the remaining components were adjusted as shown in Table 1, .

3. Preparation of anisotropic conductive film

The prepared conductive layer and insulating layer were adhered at 40 占 폚 and 1 MPa through a laminating process to obtain a two-layered anisotropic conductive film (thickness: 18 占 퐉) in which an insulating layer was laminated on the conductive layer.

Example 2

An anisotropic conductive film of Example 2 was produced in the same manner as in Example 1 except that silica having a particle diameter of 12 nm (PM-20, Tokuyama) was used as the first inorganic filler.

Example 3

An anisotropic conductive film of Example 3 was produced in the same manner as in Example 1, except that silica (SC2030, Admatech) surface-treated with epoxy having a particle diameter of 500 nm was used as the second inorganic filler .

Example 4

The anisotropic conductive films of Example 4 were prepared in the same manner as in Example 1 except that the content of each component was adjusted as shown in Table 1 below.

Comparative Example 1

The anisotropic conductive film of Comparative Example 1 was produced in the same manner as in Example 1 except that the second inorganic filler was not used and the content of each component was adjusted as shown in Table 1 below Respectively.

Comparative Example 2

The anisotropic conductive film of Comparative Example 2 was produced in the same manner as in Example 1 except that the first inorganic filler was not used and the content of each component was adjusted as shown in Table 1 below Respectively.

The contents and specifications of each component used in the above Examples and Comparative Examples are shown in Table 1 below. The following amounts are all expressed by weight%.

Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Conductive layer Binder resin 20 20 20 13 31 20 Epoxy resin 1 10 10 10 7 16 10 Epoxy resin 2 5 5 5 3 8 5 The first inorganic filler 3
(R812, 7 nm) 3
(PM-20, 14 nm) 3
(R812, 7 nm) 5
(R812, 7 nm) 3 - The second inorganic filler 20
(YA050C, 50 nm) 20
(YA050C, 50 nm) 20
(SC2030, 500 nm) 30
(YA050C, 50 nm) - 23 Conductive particle 40 40 40 40 40 40 Hardener 2 2 2 2 2 2 Sum 100 100 100 100 100 100 Insulating layer Binder resin 20 20 20 8 44 23 Epoxy resin 1 10 10 10 4 23 11 Epoxy resin 2 10 10 10 3 23 11 The first inorganic filler 5
(R812, 7 nm) 5
(PM-20, 14 nm) 5
(R812, 7 nm) 10
(R812, 7 nm) 5 - The second inorganic filler 50
(YA050C, 50 nm) 50
(YA050C, 50 nm) 50
(SC2030, 500 nm) 70
(YA050C, 50 nm) - 50 Hardener 5 5 5 5 5 5 Sum 100 100 100 100 100 100

Experimental Example

The anisotropic conductive films of Examples 1 to 4 and Comparative Examples 1 and 2 were evaluated for the rate of increase in spreading length, storage elastic modulus, minimum melt viscosity, particle capture rate, initial and reliability connection resistance, initial and reliability After the evaluation, the shot incidence was measured and the results are shown in Table 2 below.

EXPERIMENTAL EXAMPLE 1 Measurement of Growth Rate of Spreading Length

A sample having a width of 2 mm and a length of 20 mm was prepared. The glass substrate was placed on top and bottom of the anisotropic conductive film and pressed at 70 DEG C for 1 second and at a pressure of 1.0 MPa. Lt; / RTI > In this case, the length of the layer in the width direction before pressing was measured, and the increase in length in the width direction of the layer was expressed as an increase rate (%) of the spreading length according to the following formula 1.

 [Formula 1]

(%) = [(Length in the width direction of the layer after compression-length in the width direction of the layer before compression) / length in the width direction of the layer before compression] × 100

Experimental Example 2: Measurement of storage modulus

Each of the prepared anisotropic conductive films was allowed to stand in a hot air oven at 150 DEG C for 2 hours and then measured at a heating rate of 5 DEG C / min from 0 DEG C to 100 DEG C using DMA (Dynamic Mechanical Analyzer; Lt; 0 > C.

Experimental Example 3: Measurement of the lowest melt viscosity

The anisotropic conductive films prepared in the above Examples and Comparative Examples were subjected to a measurement with a sample thickness of 150 占 퐉, a temperature raising rate of 10 占 폚 / min, a strain of 5%, an angular frequency of 1.0 rad / The lowest melt viscosity was measured in the range of 0 to 250 캜.

Experimental Example 4: Measurement of melt viscosity variation value

The anisotropically conductive films produced in the above Examples and Comparative Examples were subjected to ARES G2 rheometer (TA Instruments) to calculate the melt viscosity variation by the following equation (3).

[Formula 3]

(Melt viscosity of the film at 75 DEG C - Melt viscosity of the film at 55 DEG C) / (75 DEG C - 55 DEG C)

Experimental Example 5: Measurement of particle capture rate

With respect to the anisotropic conductive films produced in the Examples and Comparative Examples, the number of conductive particles (mm ² ) per unit area of the pressure-contact prior anisotropic conductive film was calculated using a particle automatic meter (ZOOTUS).

Further, an anisotropic conductive film was placed on a glass substrate (Neoview Kolon) having an indium tin oxide circuit having a bump area of 1,200 mu m ² and a thickness of 2,000 ANGSTROM and pressurized at 70 DEG C for 1 second at 1 MPa, removed and the bump area 1200㎛ ^2, 1.5T of the IC chip thickness (manufactured by Samsung LSI) into the condition of the back this raised the 150 ℃, 5 chogan 80MPa and pressing, and the connection portion per unit area (mm ²⁾ conductive particles The number of particles was calculated using the particle automatic meter, and the particle capture rate was calculated by the following equation (2).

[Formula 2]

(Mm ² ) number of conductive particles per unit area (mm ² ) of anisotropically conductive film before compression bonding (%) = (number of conductive particles per unit area (mm ² )

Experimental Example 6: Measurement of connection resistance after initial and reliability evaluation

The anisotropic conductive films prepared in the above Examples and Comparative Examples were placed on a glass substrate (Neoview Kolon) having an indium tin oxide circuit with a bump area of 1,200 mu m ² and a thickness of 2,000 ANGSTROM and were pressed at 70 DEG C for 1 second at 1 MPa After releasing the release film, the IC chip having a bump area of 1,200 mu m ² and a thickness of 1.5T was placed on a Samsung LSI chip, followed by compression bonding at 150 DEG C for 5 seconds and 80 MPa. The resistance between the four points was measured using a resistance meter (2000 Multimeter, Keithley) using the probe method and expressed as an initial connection resistance. Thereafter, the sample was left for 500 hours under the conditions of a temperature of 85 ° C and a relative humidity of 85%, and the resistance was measured in the same manner.

The resistance measuring instrument is applied with 1 mA, and the resistance is calculated by the measured voltage and averaged.

Experimental Example 7: Measurement of shot incidence after initial and reliability evaluation

The anisotropic conductive films prepared in Examples 1 to 5 and Comparative Examples 1 and 2 were cut into 2 mm x 25 mm and bonded to insulation resistance evaluation materials, respectively. In other words. The anisotropic conductive film was placed on a glass substrate having a thickness of 0.5 mm and heated / pressed under the conditions of 70 DEG C, 1 MPa, and 1 sec to remove the release film. Thereafter, a chip (chip length 19.5 mm, chip width 1.5 mm, bump spacing 8 탆) was placed on the anisotropically conductive film, followed by compression bonding at 150 캜, 70 MPa, and 1 sec. After that, 50V was applied and the occurrence of a short circuit was checked at a total of 38 points by the two-terminal method, and an initial shot incidence rate was measured. Thereafter, the produced circuit device was left for 500 hours under the conditions of a temperature of 85 캜 and a relative humidity of 85%, and then the reliability shot occurrence rate was measured in the same manner.

Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Spreading length increase rate (%) of insulating layer 87 84 90 95 68 92 Growth rate (%) of spreading of conductive layer 35 32 36 42 24 56 Storage modulus (GPa) 4.4 4.2 4.3 4.8 2.2 4.2 The lowest melt viscosity (Pa · s) 31,684 42,534 41,725 29,875 118,101 8,754 Melt viscosity (Pa · s) 55 ° C 34,462 46,332 42,309 31,291 467,327 31,078 75 ℃ 33,402 44,709 44,440 30,510 130,308 10,177 Change in melt viscosity 0.15 0.16 0.17 0.14 0.28 0.22 Particle capture rate (%) 40 35 38 43 25 Not measurable Initial connection resistance (Ω) 0.05 0.05 0.05 0.06 0.05 1.25 Connection resistance (Ω) after reliability evaluation 0.12 0.22 0.15 0.1 3.7 8.57 Initial shortage rate (%) 0 0 0 0 18 37 Shortage rate after reliability evaluation (%) 0 0 0 0 27 52

As shown in Table 2, in the case where the inorganic filler containing two kinds of inorganic fillers having different particle diameters and having a higher rate of increase of the spreading length of the insulating layer, a melt viscosity variation value of 0 to 0.2 and a storage elastic modulus of 2.5 to 5 GPa 1 to 4 exhibited a good particle capture rate and improved initial and reliable connection resistance and shot generation characteristics.

In the case of Comparative Example 1 in which the inorganic filler having a particle size of 50 nm to 1,000 nm was excluded from both types of silica, the particle capture rate was low and there was no problem in the initial connection performance. However, since the reliability was increased, the connection resistance was increased and the melt viscosity fluctuation value was high, In the case of Comparative Example 2 in which the inorganic filler having a particle size of 1 nm to 40 nm was excluded, it was difficult to form a film of the conductive layer, so that the conductive particles were easily aggregated in the film, resulting in unstable connection resistance after initial and reliable, Higher viscosity fluctuation results in lower insulation performance and higher shot generation rates.

Claims (17)

1. An anisotropic conductive film comprising two kinds of inorganic fillers each containing a conductive layer and an insulating layer and having different particle diameters,
The anisotropic conductive film is press-bonded under the conditions of 50 DEG C to 80 DEG C for 1 to 3 seconds and 1.0 MPa to 3.0 MPa and compression bonded at 120 DEG C to 160 DEG C for 3 to 6 seconds under pressure conditions of 60 MPa to 90 MPa The increase rate of the spreading length represented by the following formula 1 is the insulating layer> the conductive layer, the curing rate is 90% or more, the storage elastic modulus when cured is 2.5 to 5 GPa,
[Formula 1]
(Length in the width direction of the layer after compression - length in the width direction of the layer before compression) / length in the width direction of the layer before compression] x 100,
Wherein the two types of inorganic fillers having different particle diameters are included in the conductive layer and the insulating layer, respectively. The anisotropic conductive film according to claim 1, wherein an increase rate of the spreading length of the insulating layer is 60 to 120% and an increase rate of the spreading length of the conductive layer is 10 to 60%. The anisotropic conductive film according to claim 1, wherein the difference in the rate of increase of the spreading length of the conductive layer and the rate of increase in the spreading length of the insulating layer is 40% to 80%. The method for producing an anisotropic conductive film according to claim 1, wherein the anisotropic conductive film is pressed under conditions of 50 DEG C to 80 DEG C for 1 to 3 seconds and 1.0 MPa to 3.0 MPa and subjected to a pressure condition of 120 to 160 DEG C for 3 to 6 seconds and 60 to 90 MPa , And the particle-trapping ratio according to the following formula (2) is 20 to 60%, as measured after compression.
[Formula 2]
(Mm ² ) number of conductive particles per unit area (mm ² ) of anisotropically conductive film before compression bonding (%) = (number of conductive particles per unit area (mm ² ) The method for producing an anisotropic conductive film according to claim 1, wherein the anisotropic conductive film is pressed under conditions of 50 DEG C to 80 DEG C for 1 to 3 seconds and 1.0 MPa to 3.0 MPa and subjected to a pressure condition of 120 to 160 DEG C for 3 to 6 seconds and 60 to 90 MPa , And then left for 500 hours under the conditions of a temperature of 85 캜 and a relative humidity of 85%. After the reliability evaluation, the anisotropic conductive film had a connection resistance of 5 Ω or less. The anisotropic conductive film according to claim 1, wherein the anisotropic conductive film has a minimum melt viscosity at 50 ° C to 100 ° C of 1,000 to 100,000 Pa · s. The method for producing an anisotropic conductive film according to claim 1, wherein the anisotropic conductive film is pressed under conditions of 50 to 80, 1 to 3 seconds, and 1.0 MPa to 3.0 MPa, under 120 to 160 ° C for 1 to 5 seconds and under pressure conditions of 60 to 90 MPa Wherein an initial shot incidence measured after compression is 0%. The method for producing an anisotropic conductive film according to claim 1, wherein the anisotropic conductive film is pressed under conditions of 50 to 80, 1 to 3 seconds, and 1.0 MPa to 3.0 MPa, under 120 to 160 ° C for 1 to 5 seconds and under pressure conditions of 60 to 90 MPa The anisotropic conductive film according to claim 1, wherein the anisotropic conductive film has a reliability shot occurrence ratio of 0% as measured by allowing to stand for 500 hours under conditions of a temperature of 85 ° C and a relative humidity of 85%. The anisotropic conductive film according to claim 1, wherein the melt viscosity variation value represented by the following formula 3 is 0 to 0.2.
[Formula 3]
(Melt viscosity of the film at 75 DEG C - Melt viscosity of the film at 55 DEG C) / (75 DEG C - 55 DEG C) The anisotropic conductive film according to claim 1, wherein the two kinds of inorganic fillers comprise 20 to 80% by weight based on the total weight of the anisotropic conductive film. delete The anisotropic conductive film according to claim 1, wherein the two kinds of inorganic fillers comprise a first inorganic filler having a particle diameter of 1 to 40 nm and a second inorganic filler having a particle diameter of 50 to 1,000 nm. The anisotropic conductive film according to claim 12, wherein the weight ratio of the first inorganic filler and the second inorganic filler is 1: 2 to 1:10. The anisotropic conductive film according to claim 12, wherein the second inorganic filler is surface-treated with a compound selected from the group consisting of a phenylamino group, a vinyl group, a phenyl group, an epoxy group and a methacryl group. 2. The method of claim 1, wherein the conductive layer and the insulating layer
Binder resin;
Epoxy resin; And
An anisotropic conductive film further comprising a curing agent. The anisotropic conductive film according to claim 1, wherein the anisotropic conductive film is used in a COG (chip on glass) or COF (chip on film) mounting method. A first connected member containing a first electrode;
A second connected member containing a second electrode; And
The method according to any one of claims 1 to 10, 12 to 16, wherein the first electrode and the second electrode are located between the first connected member and the second connected member and connect the first electrode and the second electrode. A connection structure connected by a conductive film.

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