KR101991992B1 - Anisotropic conductive film and a connection structure using thereof - Google Patents

Abstract

An embodiment of the present invention provides an anisotropic conductive film having a DSC phase initiation temperature of 75 占 폚 to 90 占 폚 and a melt viscosity variation value of 0 to 300 as represented by the following formula (1).
[Formula 1]
Melting viscosity variation = | (melt viscosity of the film at 75 占 폚 - melt viscosity of the film at 55 占 폚) / (75 占 폚 - 55 占 폚)

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. The circuit terminals are electrically connected by the conductive particles and the insulating adhesive resin is filled between the adjacent electrodes so that the conductive particles are electrically connected to each other They are isolated from each other, thereby giving high insulation.

In the conventional anisotropic conductive film, a composition flow including conductive particles is generated by heat and pressure in the process of connecting the terminals through the above hot pressing process, and the connection efficiency is increased because the particle efficiency for expressing connection characteristics between the terminals is extremely low In addition, there is a problem that a part of the composition containing the conductive particles flows into the adjacent space (space), and the conductive particles collect on a narrow area, causing a short.

Therefore, it is necessary to develop an anisotropic conductive film which is excellent in the inter-terminal connection property and can prevent short-circuit between the electrodes while sufficiently filling the insulating adhesive resin between the adjacent electrodes.

An object of the present invention is to provide an anisotropic conductive film which is excellent in connection reliability between terminals connected to each other and can prevent a short between adjacent electrodes.

In one embodiment of the present invention, there is provided an anisotropic conductive film having an initiation temperature of 75 deg. C to 90 deg. C on a DSC and a melt viscosity variation value of 0 to 300 as represented by the following formula (1).

[Formula 1]

Melting viscosity variation = | (melt viscosity of the film at 75 占 폚 - melt viscosity of the film at 55 占 폚) / (75 占 폚 - 55 占 폚)

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 can improve the reliability of connection between terminals by controlling the flowability of the film by controlling the melt viscosity, and also can prevent a short between adjacent electrodes.

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 the present invention is not limited to these embodiments.

An embodiment of the present invention relates to an anisotropic conductive film having a DSC phase initiation temperature of 75 ° C to 90 ° C and a melt viscosity variation value of 0 to 300 as represented by the following formula (1).

[Formula 1]

Melting viscosity variation = | (melt viscosity of the film at 75 占 폚 - melt viscosity of the film at 55 占 폚) / (75 占 폚 - 55 占 폚)

In the anisotropic conductive film of the present invention, the onset temperature of the DSC is 75 占 폚 to 90 占 폚. Onset temperature on DSC refers to the temperature at which the slope of the graph is firstly increased by heat generated by heat differential scanning calorimetry. The temperature at the point of contact is obtained as the start temperature. When the exothermic initiation temperature satisfies the above range, rapid curing is possible for 5 seconds under a pressure of 50 MPa to 90 MPa at a low temperature of 120 to 160 캜.

On the other hand, the anisotropic conductive film of the present invention may have an exothermic peak temperature of 90 DEG C to 105 DEG C on a thermal differential scanning calorimeter, and an exothermic peak temperature refers to a temperature at the time of peak temperature of the graph when measured by a thermal differential scanning calorimeter. When the exothermic peak temperature is in the above range, it can be cured at a relatively low temperature of 160 ° C or less, specifically 150 ° C or less, more specifically 140 ° C or less, and there is little difference between the initiation temperature and the exothermic peak temperature, .

As a non-limiting example of measuring the initiation temperature and the exothermic peak temperature on the DSC, the curable resin composition is heated at 10 ° C / min under a nitrogen gas atmosphere using a thermal differential scanning calorimeter (DSC, TA instruments, Q20) min at a temperature in the range of 0 占 폚 to 250 占 폚.

The calorific value on the thermal differential scanning calorimeter can be calculated by a commonly used method. For example, the anisotropic conductive film may be measured by a thermal differential scanning calorimeter (DSC, TA instruments, Q20) under a nitrogen gas atmosphere And can be calculated by measuring the calorie according to the temperature at a rate of 10 캜 / min from 0 캜 to 250 캜.

On the other hand, the melt viscosity change value of the anisotropic conductive film of the present invention represented by the above-mentioned formula 1 may be 0 to 300, specifically 0 to 200. When the melt viscosity variation value satisfies the above range, the melt viscosity is maintained substantially constant over a certain temperature range, so that the flowability of the composition in the film is controlled during low temperature fast curing, and the indentation can be improved. As a result, the reliability of connection between the terminals is improved, and short-circuiting between adjacent electrodes can be prevented.

Furthermore, the anisotropic conductive film may have a minimum melt viscosity at 50 to 100 of 1,000 to 100,000 Pa · s. Specifically 10,000 to 100,000 Pa · s. Within the above range, the anisotropic conductive film exhibits appropriate fluidity so that pressurization and final pressing can be performed, and the capture rate of the conductive particles can be improved.

A method of measuring the melt viscosity is not particularly limited, and examples thereof are as follows. Nonlimiting examples are as follows: Using a ARES G2 Rheometer (TA Instruments), a sample having a thickness of 150 mu m, 5% and an angular velocity of 1.0 rad / sec. The melt viscosity of the anisotropic conductive film is measured in the range of 0 ° C to 250 ° C.

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 then the storage elastic modulus at 30 DEG C is measured using DMA (Dynamic Mechanical Analyzer; can do.

The anisotropic conductive film is press-bonded under the conditions of 50 to 80 ° C for 1 to 3 seconds and 1.0 to 3.0 MPa, and finally subjected to compression bonding at 120 to 160 ° C for 5 to 6 seconds under pressure conditions of 50 MPa to 90 MPa The particle capture rate measured according to the following formula 2 may be 20 to 50%. Specifically, it may be from 25 to 45%, and more specifically from 30 to 40%.

[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 conductive particles are sufficiently located on the terminals within the above range, the electric conductivity is improved, and the outflow of the conductive particles is reduced, and the short-circuit between the terminals can be reduced.

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 70 MPa. The number of conductive particles (mm ² ) per unit area of the connection site was calculated using a particle automatic meter, To calculate the particle capture rate.

The anisotropically 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 5 to 6 seconds under pressure conditions of 50 to 90 MPa The connection resistance can be 0.5 Ω or less after the reliability evaluation as measured after being left for 500 hours at a temperature of 85 캜 and a relative humidity of 85%. Specifically, it may be 0.3 이하 or less, more specifically, 0.2 이하 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.

On the other hand, the initial connection resistance measured before leaving for 500 hours under the conditions of a temperature of 85 캜 and a relative humidity of 85% may be less than 0.2?, Specifically less than or equal to 0.1?.

The initial connection resistance and the method of measuring the connection resistance after the reliability evaluation are not particularly limited, and a non-limiting example is as follows: An anisotropic conductive film is formed on a glass with an indium tin oxide circuit having a bump area of 1200 탆 ² and a thickness of 2,000 Å The substrate was placed on a substrate and pressurized under the conditions of 70 ° C., 1 second and 1 MPa. Thereafter, the release film was removed and IC chips having a bump area of 1200 μm ² and a thickness of 1.5 T were placed thereon. And the resistance between the four points is measured using a 4 point probe method using a resistance measuring instrument (2000 Multimeter, Keithley) and expressed as an initial connecting 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 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 pressure bonded at 120 to 160 DEG C for 3 to 5 seconds under a pressure of 50 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: An 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 μm) is placed on the anisotropic conductive film, followed by compression bonding at 150 ° C., 70 MPa, and 5 sec. Thereafter, 50 V is applied and the occurrence of a short circuit is checked at a total of 38 points by the two-terminal method, and the initial short-circuit occurrence rate is measured.

The anisotropically 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, compressed and bonded at 120 to 160 DEG C for 5 to 6 seconds under pressure conditions of 50 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.

The anisotropic conductive film may include a binder resin, an epoxy resin, an inorganic filler, 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, in consideration of the activity of the cationic curing agent to be described later, 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 20 to 35% 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 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 inorganic filler may be contained in an amount of 15 to 40% by weight based on the total weight of the anisotropic conductive film, and specifically 20 to 40% by weight. The conductive particles can be effectively dispersed within the above range and the fluidity of the anisotropic conductive film can be appropriately controlled.

In one embodiment, the inorganic filler may have an average particle size ranging from 10 nm to 500 nm.

When the inorganic filler has an average particle diameter in the above range, the dispersibility of the conductive particles can be improved, the storage elastic modulus can be increased, the particle capture rate can be increased, and the shot generation rate can be lowered .

On the other hand, the curing agent may be a cationic curing agent, specifically, a sulfone curing agent represented by the following formula (1) or a quaternary ammonium curing agent represented by the following formula (2).

[Chemical Formula 1]

(2)

(R8, R9, R10, R11로 변경)

(Changed to R8, R9, R10, R11)

Wherein R ₁ to R ₅ each represent a hydrogen atom, a C 1-6 alkyl group, an acetyl group, an alkoxycarbonyl group, a benzoyl group or a benzyloxycarbonyl group, R ₆ and R ₇ each represent an alkyl group, a benzyl group, an o- A methylbenzyl group, an m-methylbenzyl group, a p-methylbenzyl group or a naphthylmethyl group,

Wherein R ₈ , R ₉ , R ₁₀ and R ₁₁ are each a substituted or unsubstituted C ₁ to C ₆ alkyl or C ₆ to C ₂₀ aryl, M ^- is Cl, BF _{4 , PF 6, N (CF 3} SO 2) 2, CH 3 CO 2, CF 3 CO 2, CF 3 SO 3, HSO 4, SO 4 2, SbF 6 -, B (C 6 F 5) 4 - is one of the .

Specifically, in the quaternary ammonium compound of Formula 2, R ₈ , R ₉ , R _10, and R _{11 each} independently represents a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, An n-pentyl group, a t-pentyl group, an isopentyl group, a hexyl group, a cyclohexyl group, a phenyl group, an anthryl group and a phenanthryl group. The group which may be substituted when the term "substituted" is used herein may be, for example, an alkyl group, an alkoxy group, an amino group, a halogen or a nitro group.

The quaternary ammonium compound accelerates the ring-opening reaction of the epoxy compound at a specific temperature and can quickly cure the epoxy compound at a temperature of 160 ° C or lower, more specifically 150 ° C or lower, more specifically 140 ° C or lower. Furthermore, the quaternary ammonium compound can delay the ring-opening reaction of the epoxy compound and provide excellent storage stability at a temperature lower than the curing temperature, for example, at room temperature.

In the formula (2), M ^- may be specifically one of SbF ₆ ^- and B (C ₆ F ₅ ) ₄ ^- . More specifically, M ^- can be B (C ₆ F ₅ ) ₄ ^- , which is preferred because it does not cause environmental problems.

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 anisotropic conductive film according to an embodiment of the present invention may have a single conductive layer structure, but is not limited thereto, and may be a multi-layer 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 multilayer 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.

Meanwhile, when the anisotropic conductive film is a multilayer structure including a conductive layer and an insulating layer, the insulating layer may include other components than the conductive particles among components that may be included in the conductive layer. The respective components are as described above. The content of each component in the anisotropic conductive film is controlled such that the weight ratio of each component in the conductive layer and the insulating layer is such that the final weight ratio of each component relative to the weight of the conductive layer and the insulating layer is the above-mentioned weight ratio.

In one embodiment, the anisotropic conductive film may be one used in a COG (chip on glass) 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. (3) described herein, which is located between the first connected member (50) and the second connected member (60) and connects the first electrode (70) and the second electrode The anisotropic conductive film 10 including the anisotropic conductive film 10 is formed.

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.

Those skilled in the art will not elaborate on the details that can be sufficiently technically derived.

On the other hand, the anisotropic conductive films of the following examples and comparative examples are in the form of an anisotropic conductive film used for connecting a panel glass to an IC, and have a two-layer structure of a conductive layer containing conductive particles and an insulating layer not containing conductive particles However, the present invention is not limited to the specific layer structure.

Example

Example  One

One. The  Produce

21.5 wt.% Of a biphenyl fluorene type binder resin (FX-293, Shinil Chemical Co., Ltd., Tg: 165 DEG C, molecular weight: 45,000), 21.5 wt.% Of an epoxy resin (Celloxide 2021P, DAICEL) 14 wt% of silica (YA050C, Admatech) of 50 nm, 3 wt% of a cationic curing agent (SI-B3A, Sanxin Chemical) and 40 wt% of conductive particles (KSFD, average particle diameter 3.0 탆, NCI) Respectively. The conductive layer composition was coated on a release film, and the solvent was evaporated in a drier at 60 캜 for 5 minutes to obtain a dried conductive layer having a thickness of 6 탆.

2. Insulating layer  Produce

A dry insulating layer having a thickness of 12 탆 was prepared under the same conditions and in the same manner as in the production of the conductive layer except that conductive particles were omitted from the composition of the conductive layer.

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. The final content of each component in the anisotropic conductive film was 31 wt% for a biphenyl fluorene type binder resin (FX-293, Shinil Chemical Co., Tg: 165 캜, molecular weight: 45,000), 31 wt% for an epoxy resin (Celloxide 2021P, DAICEL) 20% by weight of silica (YA050C, Admatech) having a particle diameter of 50 nm as an inorganic filler surface treated with phenylamino, 4% by weight of a cationic curing agent (SI-B3A, SANSHIN CHEMICAL), conductive particles (KSFD, 13% by weight.

In the following Examples 2 and 3 and Comparative Examples 1 and 2, an anisotropic conductive film (thickness: 18 μm) having a two-layer structure in which an insulating layer was laminated on a conductive layer was prepared similarly to Example 1, In Examples and Comparative Examples, an insulating layer was obtained by using a composition except for conductive particles in each conductive layer composition. Therefore, in order to avoid redundant explanations, only differences in conductive layer compositions including conductive particles and contents of respective components in the final anisotropic conductive film in Examples 2, 3, and Comparative Examples 1 and 2 described below will be described.

Example  2

16 wt% of a biphenyl fluorene type binder resin (FX-293, Shinil Chemical Co., Ltd., Tg: 165 캜, molecular weight: 45,000), 16 wt% of an epoxy resin (Celloxide 2021P, DAICEL) And 25% by weight of silica having a particle diameter of 50 nm (YA050C, Admatech) surface-treated with phenylamino as an inorganic filler were used in place of the anisotropic conductive film of Example 2.

The final content of each component in the anisotropically conductive film was 23% by weight of a biphenyl fluorene type binder resin (FX-293, Shinil Chemical Co., Tg: 165 캜, molecular weight: 45,000), 23% by weight of an epoxy resin (Celloxide 2021P, DAICEL) 36% by weight of silica (YA050C, Admatech) having a particle diameter of 50 nm as an inorganic filler surface treated with phenylamino, 4% by weight of a cationic curing agent (SI-B3A, Sanxin Chemical), conductive particles (KSFD, 13% by weight.

Example  3

14.5 wt% of a biphenyl fluorene type binder resin (FX-293, Shinil Chemical Co., Ltd., Tg: 165 DEG C, molecular weight: 45,000), 14.5 wt% of an epoxy resin (Celloxide 2021P, DAICEL) And 28% by weight of silica having a particle diameter of 50 nm (YA050C, Admatech) surface-treated with phenylamino as an inorganic filler were used in place of the anisotropic conductive film of Example 3.

The final content of each component in the anisotropic conductive film was 21 wt% for a biphenyl fluorene type binder resin (FX-293, Shinil Chemical Co., Tg: 165 캜, molecular weight: 45,000), 21 wt% for an epoxy resin (Celloxide 2021P, DAICEL) 40% by weight of silica (YA050C, Admatech) having a particle diameter of 50 nm as an inorganic filler surface treated with phenylamino, 4% by weight of a cationic curing agent (SI-B3A, Sanxin Chemical), conductive particles (KSFD, 13% by weight.

Comparative Example  One

27% by weight of a biphenyl fluorene type binder resin (FX-293, Shinil Chemical Co., Tg: 165 DEG C, molecular weight: 45,000), 27% by weight of an epoxy resin (Celloxide 2021P, DAICEL) And 3% by weight of silica having a particle diameter of 50 nm (YA050C, Admatech) surface-treated with phenylamino as an inorganic filler were used in place of the anisotropic conductive film of Comparative Example 1.

The final content of each component in the anisotropically conductive film was 39 wt% of a biphenyl fluorene type binder resin (FX-293, Shinil Chemical Co., Tg: 165 캜, molecular weight: 45,000), 39 wt% of an epoxy resin (Celloxide 2021P, DAICEL) 4 wt% of an inorganic filler, 4 wt% of a cationic curing agent (SI-B3A, Sanshin Chemical), and 13 wt% of conductive particles (KSFD, average particle diameter 3.0 탆, NCI).

Comparative Example  2

11 wt% of a biphenyl fluorene type binder resin (FX-293, Shinil Chemical Co., Tg: 165 캜, molecular weight: 45,000), 11 wt% of an epoxy resin (Celloxide 2021P, DAICEL) And 35% by weight of silica having a particle diameter of 50 nm (YA050C, Admatech) surface-treated with phenylamino as an inorganic filler were used in place of the anisotropic conductive film of Comparative Example 2.

The final content of each component in the anisotropic conductive film was 16% by weight of biphenyl fluorene type binder resin (FX-293, Shinil Chemical Co., Tg: 165 캜, molecular weight: 45,000), 16% by weight of epoxy resin (Celloxide 2021P, DAICEL) , 51% by weight of silica (YA050C, Admatech) having a particle size of 50 nm and surface treated with phenylamino as an inorganic filler, 4% by weight of a cationic curing agent (SI-B3A, Sanxin Chemical), conductive particles (KSFD, 15% by weight.

The contents of the respective components in the conductive layer and the anisotropic conductive film in the examples and comparative examples are shown in the following Tables 1 and 2, respectively. The following amounts are all expressed by weight%.

Conductive layer

Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Binder resin 21.5 16 14.5 27 11 Epoxy resin 21.5 16 14.5 27 11 Inorganic filler 14 25 28 3 35 Hardener 3 3 3 3 3 Conductive particle 40 40 40 40 40 Sum 100 100 100 100 100

Anisotropic conductive film

Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Binder resin 31.03 23.11 20.95 39 15.89 Epoxy resin 31.03 23.11 20.95 39 15.89 Inorganic filler 20.28 36.12 40.44 4.34 50.56 Hardener 4.33 4.33 4.33 4.33 4.33 Conductive particle 13.33 13.33 13.33 13.33 13.33 Sum 100 100 100 100 100

Experimental Example

The prepared anisotropic conductive films of Examples 1 to 3 and Comparative Examples 1 and 2 were evaluated for the lowest melt viscosity, storage elastic modulus, particle capture rate, initial and reliability connection resistance, And the results are shown in Table 3 below.

Experimental Example  1: Anisotropic conductive film Thermal differential scanning calorimeter ( DSC ) Onset temperature and exothermic peak temperature calculation

The anisotropic conductive films of Examples 1 to 3 and Comparative Examples 1 and 2 were measured at a rate of 10 ° C / min in a nitrogen gas atmosphere using a differential scanning calorimeter (DSC, TA Instruments Co., Ltd., Q20) at 0 ° C To 250 ° C to determine the onset temperature and the exothermic peak temperature of the thermal differential scanning calorimeter.

Experimental Example  2: Measurement of melt viscosity

The anisotropic conductive films prepared in the above Examples and Comparative Examples were subjected to measurement of a sample thickness of 150 占 퐉, a temperature raising rate of 10 占 폚 / min, a strain of 5% and an angular velocity of 1.0 rad / sec using an ARES G2 rheometer (TA Instruments) The melt viscosity was measured in the range of 0 ° C to 250 ° C.

Experimental Example  3: Melt viscosity  Measure change

The anisotropically conductive films produced in the Examples and Comparative Examples were measured for melt viscosity variation by the following formula 1 using an ARES G2 rheometer (TA Instruments).

[Formula 1]

Melting viscosity variation = | (melt viscosity of the film at 75 占 폚 - melt viscosity of the film at 55 占 폚) / (75 占 폚 - 55 占 폚)

Experimental Example  4: 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; Q800, TA company) Lt; 0 > C.

Experimental Example  5: Particle capture rate  Measure

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 70MPa 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 having 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 removing the release film, an IC chip (manufactured by SAMSUNG LSI) having a bump area of 1,200 μm ² and a thickness of 1.5 T was placed, and the resultant was compression-bonded at 150 ° C. for 5 seconds and 70 MPa to prepare a test piece. Using the probe method, the resistance between four points was measured using a resistance measuring instrument (2000 Multimeter, Keithley) 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: Short after initial and reliability evaluation Incidence rate  Measure

The anisotropic conductive films prepared in the above Examples and Comparative Examples were cut into 2 mm x 25 mm and bonded to the 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 5 sec. Thereafter, 50V was applied and the occurrence of a short was checked at a total of 38 points by the two-terminal method, and the initial shot incidence 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 generation rate was measured in the same manner.

Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Starting temperature (° C) on thermal differential scanning calorimeter (DSC) 85 87 87 83 89 Exothermic peak temperature (DSC) on a differential scanning calorimeter (DSC) 100 101 102 98 104 The lowest melt viscosity (Pa · s) 31684 47033 94024 9016 801684 Melt viscosity (Pa · s) 55 ° C 34461.7 52440.4 97923.0 210294.0 814461.7 75 ℃ 32401.5 54309.1 94023.6 9055.7 802401.5 Change in melt viscosity 103.01 93.43 194.97 10061.92 603.01 Storage modulus (GPa) 3.5 3.7 4.1 2.1 4.3 Particle capture rate (%) 32 35 38 18 42 Initial connection resistance (Ω) 0.05 0.06 0.08 0.05 0.6 Connection resistance (Ω) after reliability evaluation 0.1 0.12 0.2 0.2 3 Initial shortage rate (%) 0 0 0 0 12 Shortage rate after reliability evaluation (%) 0 0 0 0 12 Early Appearance 4 4 4.5 3 4.5 Appearance after reliability evaluation 3.5 3.5 4 1.5 2

As shown in Table 3, the initiation temperature and the exothermic peak temperature can be controlled by controlling the content of the inorganic filler while using a cationic curing agent. Furthermore, by including at least 20% by weight of the inorganic filler in the anisotropic conductive film, the minimum melt viscosity can be increased and the flowability of the anisotropic conductive film can be controlled by decreasing the melt viscosity fluctuation value.

In addition, by controlling the content of the inorganic filler in the anisotropic conductive film to 40 wt% or less, excellent initial and reliable connection resistance characteristics exhibited a satisfactory value. In addition, Examples 1 to 3 showed a storage modulus of 2.5 to 5 GPa and exhibited a good particle capture rate, and improved initial and reliability post-shot incidence characteristics, and good appearance after initial appearance and reliability evaluation.

3 conductive particles 10 anisotropic conductive film 30 connection structure
50 first connected member 60 second connected member 70 first electrode 80 second electrode

Claims (16)

Binder resin; Curable compounds; Cationic curing agents; Conductive particles; And an inorganic filler,
The starting temperature of the thermal differential scanning calorimeter (DSC) is 75 占 폚 to 90 占 폚,
An anisotropic conductive film having a melt viscosity variation value of 0 to 300 as represented by the following formula
[Formula 1]
Melting viscosity variation = | (melt viscosity of the film at 75 占 폚 - melt viscosity of the film at 55 占 폚) / (75 占 폚 - 55 占 폚)
Wherein the curable compound comprises an epoxy resin,
Wherein the inorganic filler comprises a surface-treated inorganic filler, and the inorganic filler is contained in an amount of 15 to 40% by weight based on the total weight of the anisotropic conductive film. 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 10,000 to 100,000 Pa · s. The anisotropic conductive film according to claim 1, wherein an exothermic peak temperature on a DSC is 90 ° C to 105 ° C. The anisotropic conductive film of claim 1, wherein the curing rate is 90% or more and the storage elastic modulus when cured is in the range of 2.5 to 5 GPa. The anisotropically conductive film according to claim 1, wherein the anisotropic conductive film is press-bonded under conditions of 50 ° C to 80 ° C for 1 to 3 seconds and 1.0 MPa to 3.0 MPa, under 120 to 160 ° C for 5 to 6 seconds and under a pressure of 50 MPa to 90 MPa Wherein the particle-trapping ratio according to the following formula (2) is 20% to 50%, which is measured after the main 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 anisotropically conductive film according to claim 1, wherein the anisotropic conductive film is press-bonded under conditions of 50 ° C to 80 ° C for 1 to 3 seconds and 1.0 MPa to 3.0 MPa, under 120 to 160 ° C for 5 to 6 seconds and under a pressure of 50 MPa to 90 MPa Wherein the connection resistance is 0.5 Ω or less after reliability evaluation as measured by allowing the film to stand for 500 hours at a temperature of 85 ° C. and a relative humidity of 85%. The anisotropically conductive film according to claim 1, wherein the anisotropic conductive film is press-bonded under conditions of 50 ° C to 80 ° C for 1 to 3 seconds and 1.0 MPa to 3.0 MPa, under 120 to 160 ° C for 5 to 6 seconds and under a pressure of 50 MPa to 90 MPa And an initial shot incidence rate measured after the main pressing is 0%. The anisotropically conductive film according to claim 1, wherein the anisotropic conductive film is press-bonded under conditions of 50 ° C to 80 ° C for 1 to 3 seconds and 1.0 MPa to 3.0 MPa, under 120 to 160 ° C for 5 to 6 seconds and under a pressure of 50 MPa to 90 MPa The anisotropic conductive film having a reliability shot generation rate of 0% as measured by allowing to stand for 500 hours at a temperature of 85 캜 and a relative humidity of 85% after the main compression. delete delete The anisotropic conductive film according to claim 1, wherein the inorganic filler is silica having an average particle diameter of 10 nm to 500 nm. The anisotropic conductive film of claim 1, wherein the 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. The anisotropic conductive film according to claim 1, wherein the cationic curing agent is a sulfonium salt cationic curing agent represented by the following formula (1) or a quaternary ammonium curing agent represented by the following formula (2).
(Formula 1)

(2)

Wherein R ₁ to R ₅ each represent a hydrogen atom, a C 1-6 alkyl group, an acetyl group, an alkoxycarbonyl group, a benzoyl group or a benzyloxycarbonyl group, R ₆ and R ₇ each represent an alkyl group, a benzyl group, an o- A methylbenzyl group, an m-methylbenzyl group, a p-methylbenzyl group or a naphthylmethyl group,
Wherein R ₈ , R ₉ , R ₁₀ and R ₁₁ are each a substituted or unsubstituted C ₁ to C ₆ alkyl or C ₆ to C ₂₀ aryl, M ^- is Cl ^- , BF ^{_{4 -, PF 6 -, N}} (CF 3 SO 2) 2 -, CH 3 CO 2 -, CF 3 CO 2 -, CF 3 SO 3 -, HSO 4 -, SbF 6 -, B (C 6 F 5) ₄ ^- is one of. [12] The anisotropic conductive film of claim 13, wherein the cationic curing agent comprises 1 to 10% by weight based on the total weight of the anisotropic conductive film. The anisotropic conductive film of claim 1, wherein the anisotropic conductive film is used in a COG (chip on glass) mounting method. A first connected member containing a first electrode;
A second connected member containing a second electrode; And
The anisotropic conductive film according to any one of claims 1 to 8 and claim 11 to 15, which is located between the first to-be-connected members and the second to-be-connected members and connects the first electrode and the second electrode A connected connection structure.

Images