JP6844685B2 - Pre-supplied underfill material and its cured product, electronic component equipment and its manufacturing method - Google Patents

Description

The present invention relates to a pre-supplied underfill material and a cured product thereof, and an electronic component device and a method for manufacturing the same.

Conventionally, resin encapsulation has been the mainstream technology for encapsulating elements of electronic component devices such as transistors, ICs (Integrated Circuits), and LSIs (Large-scale Integration) from the viewpoints of productivity and cost. Epoxy resin is widely used as the resin used for this purpose. This is because the epoxy resin has a good balance of various properties such as workability, moldability, electrical properties, moisture resistance, heat resistance, mechanical properties, and adhesiveness to insert products.

Epoxy resin compositions that are liquid at room temperature are widely used in bare chip mounted electronic component devices such as COB (Chip on Board), COG (Chip on Glass), and TCP (Tape Carrier Package). Further, in an electronic component device (flip chip) in which a semiconductor element is directly bump-connected on a wiring board whose substrate is ceramic, glass / epoxy resin, glass / imide resin, polyimide film, etc., the bump-connected semiconductor element is also used. An epoxy resin composition that is liquid at room temperature is used as an underfill material that fills a gap between the and the wiring board.

In bare chip mounting, the circuit forming surface is not sufficiently protected, so that moisture and ionic impurities easily infiltrate. Further, in the flip chip mounting, since the coefficient of thermal expansion differs between the semiconductor element and the wiring board, thermal stress is likely to occur at the connection portion. Therefore, the epoxy resin composition plays an important role in protecting electronic components from temperature, humidity or mechanical external forces.

As the underfill material, a material containing an epoxy resin as a curable component is known. For example, an epoxy resin composition using an imidazole compound as a curing accelerator for an epoxy resin (see, for example, Patent Document 1), and the imidazole compound as a curing accelerator for an epoxy resin may be coated with a film of a thermosetting resin. Epoxy resin compositions using at least one of the fine sphere particles or amine adduct particles (see, for example, Patent Document 2) have been reported.

As a filling method for the underfill material, after the semiconductor element and the wiring board are metal-bonded by a method such as reflow, a capillary phenomenon is used in the gap between the semiconductor element and the wiring board to create a room temperature. A capillary underfill method (post-supply method) in which a liquid epoxy resin composition is permeated is generally used. In this method, if the gap is narrowed, the filling tends to be insufficient, and voids may easily occur. As a result, after joining the semiconductor element and the wiring board, there is a concern that stress will be generated due to the volume change during cooling and the joined portion will be easily broken.

Therefore, before joining the semiconductor element and the wiring board, a liquid or solid (film-like or the like) underfill material is supplied onto the wiring board, the semiconductor element having metal bumps is thermocompression bonded, and the semiconductor element and the wiring are wired. A pre-supply method has been devised in which the bonding with the substrate and the curing reaction of the underfill material are collectively performed. The pre-supply method has the advantage that the underfill material hardens at the time of joining and the joint is immediately protected, making it easy to handle narrow pitches.

Gazette No. 7-53794 Japanese Patent No. 3446730

Attempts to use a conventional epoxy resin composition as a pre-supplied underfill material have the following problems.
The epoxy resin composition contains at least one of an epoxy resin, a curing catalyst and a curing agent, and when heat is applied, a ring-opening polymerization reaction of epoxy groups occurs to increase the molecular weight. Therefore, it takes some time for the epoxy resin composition to cure. In particular, in the case of the pre-supply method, the underfill material is supplied to the wiring board or the electronic component heated by the hot plate in the medium temperature region of about 50 ° C. to 100 ° C. Therefore, if it takes a long time to cure, voids due to moisture adhering to the wiring board, electronic components, etc., volatile compounds, and the like tend to be generated. Voids cause defects such as peeling and cracks, and may reduce reliability.

Changing the reaction mechanism of the underfill material from the epoxy ring-opening reaction to the radical polymerization reaction is an effective means for increasing the curing rate of the underfill material and suppressing the generation of voids. However, even if the reaction mechanism is an underfill material that is a radical polymerization reaction, as with the epoxy resin, the reaction in the medium temperature region gradually progresses and the viscosity increases, which may cause entrainment voids. In particular, in the pre-supply method, the underfill material may be held on the hot plate for a long time depending on the form of the package (PKG). Therefore, the pre-supplied underfill material is required to have the property of suppressing the generation of voids in the cured product even if it is left in a medium temperature region.

In view of the above circumstances, the present invention provides a pre-supplied underfill material and a cured product thereof in which the generation of voids in the cured product is suppressed even when left in a medium temperature region, and an electronic component device and a method for manufacturing the same. Make it an issue.

Means for solving the above problems include the following embodiments.
<1> 4 to 9 carbon atoms in which (A) a radically polymerizable compound, (B) a radical polymerization initiator, and (C) a reactive functional group are bonded to each other via an oxygen atom or not via an oxygen atom. A pre-supplied underfill material containing a silane compound having a structure in which a chain hydrocarbon group of the above is bonded to a silicon atom.
<2> The prior supply according to <1>, wherein the reactive functional group is a vinyl group, a glycidyl group, an acryloyl group, a methacryloyl group, a styryl group, an amino group, a ureido group, a mercapto group, a sulfide group or an isocyanate group. Mold underfill material.
<3> The silane compound is the pre-supplied underfill material according to <1> or <2>, which is represented by the following general formula (I).


[In the general formula (I), R ₁ , R ₂ and R ₃ are independently hydrogen atoms, methyl groups, methoxy groups, ethyl groups, ethoxy groups, phenyl groups or phenoxy groups, and R ₄ is a vinyl group and glycidyl. The group is a glycidyloxy group, an acryloyl group, an acryloyloxy group, a methacryloyl group, a methacryloyloxy group, a styryl group, an amino group, a ureido group, a mercapto group, a sulfide group or an isocyanate group, and n is 4 to 9. ]
<4> The pre-supplied underfill material according to any one of <1> to <3>, which further contains an inorganic filler.
<5> The pre-supplied underfill material according to any one of <1> to <4>, further containing a flexible agent.
<6> A cured product of the pre-supplied underfill material according to any one of <1> to <5>.
<7> An electronic component device containing a cured product of the pre-supplied underfill material according to <6>.
<8> A cured product of the pre-supplied underfill material having an electronic component and a wiring board that is arranged to face the electronic component and is electrically joined to the electronic component via a joint. Is the electronic component device according to <7>, which is arranged between the electronic component and the wiring board.
<9> A method for manufacturing an electronic component device, which manufactures an electronic component device by electrically joining an electronic component and a wiring board via a joint.
Item 2. The item according to any one of <1> to <5>, on at least one surface of the electronic component on the side facing the wiring board or on the surface of the wiring board facing the electronic component. Supply process for supplying pre-supply type underfill material and
A method for manufacturing an electronic component device, which comprises a joining step of joining the electronic component and the wiring board via a joining portion and curing the pre-supplied underfill material.

According to the present invention, there are provided a pre-supplied underfill material and a cured product thereof, in which the generation of voids in the cured product is suppressed even when left in a medium temperature region, an electronic component device, and a method for manufacturing the same.

It is sectional drawing explaining the process of the manufacturing method of the electronic component apparatus using the pre-supply type underfill material of liquid at 25 degreeC. It is sectional drawing explaining the process of the manufacturing method of the electronic component apparatus using the film-like pre-supply type underfill material at 25 degreeC.

Hereinafter, the present invention will be described in detail. However, the present invention is not limited to the following embodiments. In the following embodiments, the components (including element steps and the like) are not essential unless otherwise specified, unless it is clearly considered to be essential in principle. The same applies to the numerical values and their ranges, and does not limit the present invention.
In the present specification, the term "process" includes not only a process independent of other processes but also the process if the purpose of the process is achieved even if the process cannot be clearly distinguished from the other process. Is done.
In the numerical range indicated by using "~" in the present specification, the numerical values before and after "~" are included as the minimum value and the maximum value, respectively.
In the present specification, the content of each component in the underfill material is the same as the content of each component in the underfill material when a plurality of substances corresponding to each component are present in the underfill material, unless otherwise specified. It means the total content of substances.
In the present specification, the particle size of each component in the underfill material is such that when a plurality of particles corresponding to each component are present in the underfill material, the plurality of types existing in the underfill material are not specified unless otherwise specified. Means a value for a mixture of particles.
As used herein, (meth) acrylate means acrylate or methacrylate, and (meth) acryloyl means acryloyl or methacryloyl.
In the present specification, the term "layer" refers to the case where the layer is formed in the entire region when the region is observed, and the case where the layer is formed only in a part of the region. Is also included.

<Pre-supplied underfill material>
The pre-supplied underfill material of the present embodiment (hereinafter, also simply referred to as an underfill material) contains (A) a radically polymerizable compound, (B) a radical polymerization initiator, and (C) a reactive functional group of oxygen. Includes a silane compound having a structure in which a chain hydrocarbon group having 4 to 9 carbon atoms bonded to an atom or not via an oxygen atom is bonded to a silicon atom (hereinafter, also referred to as a specific silane compound). ..

Since the reaction mechanism of the underfill material of the present embodiment is a radical polymerization reaction, the speed of the curing reaction in a high temperature region is faster than that of the underfill material whose reaction mechanism is an epoxy ring-opening reaction. Furthermore, the studies by the present inventors have revealed that the inclusion of the specific silane compound in the underfill material suppresses the progress of the curing reaction in the medium temperature region. Although the reason is not clear, it is considered that the specific silane compound has high wettability with respect to a radically polymerizable compound such as a (meth) acrylate compound contained in the underfill material, has excellent compatibility, and improves thermal stability. .. Further, since the specific silane compound has a long-chain alkyl group, the surface tension is small, and it easily collects on the surface of the underfill material before curing (the portion in contact with the outside air), and the surface of the underfill material is coated with the specific silane compound. It is considered that such a state suppresses the curing reaction even if it is left in a medium temperature region for a long time.

The underfill material may be liquid or solid at room temperature. Examples of the underfill material that is solid at room temperature include a film-like underfill material.
In the present specification, "room temperature" means 25 ° C. In the present specification, "liquid" indicates fluidity and viscosity, and the viscosity, which is a measure of viscosity, is 0.0001 Pa · s to 1000 Pa at 25 ° C. -It means a substance that is s. As used herein, the term "viscosity" refers to an underfill material maintained at 25 ° C. as a shear viscosity using a rotary shear viscometer equipped with a cone plate (diameter 40 mm, cone angle 0 °). It is defined as a value measured at a shear rate of 0.0s ^{-1 at a temperature of 25 ° C.}
As used herein, the term "solid at room temperature" means a state that does not fall under the definition of "liquid at room temperature" and is not a gas.

Whether or not the reaction of the underfill material, which is liquid at room temperature, starts in the medium temperature region depends on the viscosity before and after the temperature is raised to the medium temperature region (50 ° C to 100 ° C) (and if necessary, left for a predetermined time). It can be confirmed by changes, changes in peaks (changes in reaction behavior) in differential scanning calorimetry (DSC), and the like. In the case of an underfill material that is solid at room temperature, it can be confirmed by changes in hardness or the like.
Hereinafter, each component constituting the underfill material of the present invention will be described.

(A) Radical Polymerizable Compound The underfill material contains a radically polymerizable compound. The radically polymerizable compound is not particularly limited, and a compound having an unsaturated double bond in the molecule is preferable. Examples of the radically polymerizable compound include a redox polymerizable compound, an emulsion emulsion polymerization compound and a (meth) acrylate compound. The radically polymerizable compound is preferably a (meth) acrylate compound in consideration of applicability to electronic component devices, controllability of curing rate, handleability of underfill material, and the like. As the radically polymerizable compound, one type may be used alone, or two or more types may be used in combination.

When a (meth) acrylate compound is used as the radically polymerizable compound, the content of other radically polymerizable compounds other than the (meth) acrylate compound in the total amount of all the radically polymerizable compounds contained in the underfill material is 10. It is preferably 1% by mass or less, more preferably 5% by mass or less, further preferably 1% by mass or less, and substantially no other radically polymerizable compound is contained.

The (meth) acrylate compound as the radically polymerizable compound is not particularly limited, and conventionally known (meth) acrylate compounds can be used. The (meth) acrylate compound may be used alone or in combination of two or more. The combination of the (meth) acrylate compounds when two or more kinds of (meth) acrylate compounds are used in combination is not particularly limited. From the viewpoint of dispensability, at least one polyfunctional (meth) acrylate compound containing at least two (meth) acryloyl groups in one molecule and a monofunctional (meth) acryloyl group containing one (meth) acryloyl group in one molecule. It is preferable to use at least one (meth) acrylate compound in combination. By doing so, the underfill material often has a low viscosity, and the dispensability tends to be improved.

Examples of the polyfunctional (meth) acrylate compound include diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, trimethylol propane diacrylate, trimethylol propane triacrylate, 1,4-butanediol diacrylate, and 1 , 6-Hexanediol diacrylate, polyethylene glycol diacrylate, polypropylene glycol diacrylate, tricyclodecanedimethylol diacrylate, ditrimethylol propanetetraacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, tris ( β-Hydroxyethyl) isocyanurate triacrylate, polycarbonate acrylate, urethane acrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, trimethylolpropane dimethacrylate, trimethylolpropanetrimethacrylate, 1,4-butane Didiol dimethacrylate, 1,6-hexanediol dimethacrylate, polyethylene glycol dimethacrylate, polypropylene glycol dimethacrylate, tricyclodecanedimethylol dimethacrylate, ditrimethylol propanetetramethacrylate, pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate, dipentaerythritol Examples thereof include hexamethacrylate, trimethacrylate of tris (β-hydroxyethyl) isocyanurate, polycarbonate methacrylate, urethane methacrylate, and a bifunctional (meth) acrylate compound represented by the following structural formula (II). Among these, the liquid bifunctional (meth) acrylate compound represented by the following structural formula (II) is preferable because it is liquid at room temperature and can impart good thermal fluidity to the underfill material.

In structural formula (II), R ₁ represents a divalent organic group, R ₂ and R ₃ each independently represent a hydrogen atom or a methyl group, and m and n each independently represent a positive number. The structural unit numbers m and n indicate an integer value for a single molecule, but indicate a rational number which is an average value for an aggregate of a plurality of types of molecules.
As the _{divalent organic group represented by R 1} , a linear or branched alkylene group having 1 to 5 carbon atoms is preferable, and an alkylene group having 1 to 2 carbon atoms is more preferable from the viewpoint of the viscosity of the compound to be added. preferable. It is preferable that m and n are independently numbers 1 to 15.

Specific examples of the bifunctional (meth) acrylate compound represented by the structural formula (II) include the bifunctional (meth) acrylate compound represented by the following structural formula (III) and the following structural formula (IV). Examples thereof include bifunctional (meth) acrylate compounds.

In structural formula (III), R ₂ and R ₃ each independently represent a hydrogen atom or a methyl group, and m and n are independently positive numbers.

In structural formula (IV), R ₂ and R ₃ each independently represent a hydrogen atom or a methyl group, and m and n are independently positive numbers.

Examples of the monofunctional (meth) acrylate compound include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, and isobutyl (meth) acrylate. t-butyl (meth) acrylate, amyl (meth) acrylate, isoamyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, nonyl (meth) Acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate, lauryl (meth) acrylate, tridecyl (meth) acrylate, hexadecyl (meth) acrylate, stearyl (meth) acrylate, isostearyl (meth) acrylate, cyclohexyl (meth) acrylate , Isobornyl (meth) acrylate, tricyclo [5.2.1.02,6] decyl (meth) acrylate, 2- (tricyclo) [5.2.1.02,6] deca-3-en-8-yl Oxyethyl (meth) acrylate, 2- (tricyclo) [5.2.1.02,6] Deca-3-ene-9-yloxyethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2- Hydroxypropyl (meth) acrylate, dimerdiol mono (meth) acrylate, diethylene glycol (meth) acrylate, polyethylene glycol (meth) acrylate, polypropylene glycol (meth) acrylate, 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) ) Acrylate, 2-butoxyethyl (meth) acrylate, methoxydiethylene glycol (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, 2-phenoxyethyl (meth) acrylate, phenoxydiethylene glycol (meth) acrylate, phenoxypolyethylene glycol (meth) acrylate , 2-benzoyloxyethyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, benzyl (meth) acrylate, 2-cyanoethyl (meth) acrylate, γ- (meth) acryloyloxypropyltrimethoxysilane, Glycidyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, dicyclopentenylo Xyethyl (meth) acrylicate, dicyclopentanyl (meth) acrylicate, dicyclopentenyl (meth) acrylicate, tetrahydropyranyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) Acrylate, 1,2,2,6,6-pentamethylpiperidinyl (meth) acrylate, 2,2,6,6-tetramethylpiperidinyl (meth) acrylate, (meth) acryloxyethyl phosphate, (meth) ) Acryloyloxyethyl phenyl acid phosphate, β- (meth) acryloyloxyethyl hydrogen phthalate, β- (meth) acryloyloxyethyl hydrogen succinate and ethylene oxide-modified neopentyl glycol (meth) acrylate, 2- (meth) acryloyloxy Ethylsuccinic acid, 2-methacryloyloxyethyl hexahydrophthalic acid, isobonyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, dimethylaminoethyl (Meta) acrylate, diethylaminoethyl (meth) clearate, 2- (meth) acryloyloxyethyl phthalic acid, 2- (meth) acryloyloxyethyl-2-hydroxyethyl phthalic acid, and neopentyl glycol (meth) acrylate benzoic acid Acrylate can be mentioned.

When at least one polyfunctional (meth) acrylate compound and at least one monofunctional (meth) acrylate compound are used in combination as the radically polymerizable compound, the total amount of the polyfunctional (meth) acrylate compound and the monofunctional (meth) acrylate are used. The ratio (mass basis) of the total amount of the compounds is preferably 10: 1 to 1: 2, more preferably 8: 1 to 1: 1, and further preferably 6: 1 to 2: 1. preferable.

From the viewpoint of stress relaxation and adhesive strength of the underfill material, it is preferable to contain one or more radical polymerizable compounds having a functional group equivalent of 100 to 1300, and a radical polymerizable compound having a functional group equivalent of 250 to 800. It is more preferable to contain one or more kinds of. From the viewpoint of difficulty in curing in the medium temperature region and adhesive strength, it is more preferable to contain one or more radically polymerizable compounds having a functional group equivalent of 300 to 700.

In general, the larger the value of the functional group equivalent, the sparser the crosslinked structure formed by the curing reaction and the more the stress relaxation property tends to be improved. On the other hand, the adhesiveness at the time of heat, which has a trade-off relationship with the stress relaxation property, tends to decrease as the value of the functional group equivalent increases. The same applies when the number of functional groups in one molecule is small. From the viewpoint of achieving both stress relaxation property and excellent adhesiveness, the number of functional groups in one molecule of the radically polymerizable compound is preferably 1 to 3, and more preferably 2 or 3. As a result, an underfill material having excellent stress relaxation and excellent adhesiveness can be obtained.

Here, the functional group equivalent is the value obtained by dividing the theoretical molecular weight by the number of functional groups or the weight average molecular weight of one molecule measured by gel permeation chromatography (GPC) divided by the number of unsaturated double bonds. Define. The skeleton of a molecule that falls within that range is not specified. A radically polymerizable compound having a functional group equivalent within the above range is, for example, a compound having a functional group at the terminal and a long main chain in the molecule, a long side chain or a branch in the molecule. Examples thereof include compounds having a separated bulky side chain. When a radically polymerizable compound having a functional group equivalent within the above numerical range is used, the crosslinked structure formed by the curing reaction by light or heat tends to be sparse. When a compound having a functional group at the end and a long main chain in the molecule is used, the distance between reaction points becomes long because the functional group is at the end, which tends to relieve stress. There is a tendency. In addition, the presence of long side chains and bulky side chains tends to create spaces around them, resulting in dense and sparse parts. This tends to relieve stress. Therefore, the underfill material containing a radically polymerizable compound having a functional group equivalent of 100 to 1300 is excellent in stress relaxation property and tends to improve the adhesive force.

In the present specification, the weight average molecular weight means the weight average molecular weight measured in polystyrene conversion using gel permeation chromatography (for example, manufactured by Shimadzu Corporation, product name "C-R4A"). To do. The calibration curve was approximated by a cubic formula using a 5-sample set of standard polystyrene (PStQuick MP-H, PStQuick B [manufactured by Tosoh Corporation, trade name]). The conditions of GPC are shown below.

Equipment: (Pump: L-2130 type [manufactured by Hitachi High-Technologies Corporation]),
(Detector: L-2490 type RI [manufactured by Hitachi High-Technologies Corporation]),
(Column oven: L-2350 [manufactured by Hitachi High-Technologies Corporation])
Column: Gelpack GL-R440 + Gelpack GL-R450 + Gelpack GL-R400M (3 in total) (manufactured by Hitachi Kasei Co., Ltd., product name)
Column size: 10.7 mm (inner diameter) x 300 mm
Eluent: tetrahydrofuran Sample concentration: 10 mg / 2 mL
Injection volume: 200 μL
Flow rate: 0.05 mL / min Measurement temperature: 25 ° C

The (meth) acrylate compound having a functional group equivalent of 250 g / eq to 1300 g / eq is preferably used in combination with the (meth) acrylate compound having a functional group equivalent of less than 250. For example, the mass ratio (A1: A2) of the (meth) acrylate compound A1 having a functional group equivalent of 250 to 1300 to the (meth) acrylate compound A2 having a functional group equivalent of less than 250 is 5: 3 to 1:10. It is preferably 5: 4 to 1: 9, and even more preferably 1: 1 to 1: 8.

(B) Radical Polymerization Initiator The underfill material contains a radical polymerization initiator. The radical polymerization initiator is not particularly limited, and a conventionally known radical polymerization initiator can be used. Examples of the radical polymerization initiator include organic peroxides described later; azobisisobutyronitrile, azobis-4-methoxy-2,4-dimethylvaleronitrile, azobiscyclohexanone-1-carbonitrile, azodibenzoyl and the like. Azo compounds; Examples thereof include a water-soluble catalyst such as potassium persulfate and ammonium persulfate and a peroxide, or a redox catalyst using a combination of a persulfate and a reducing agent. The radical polymerization initiator may be used alone or in combination of two or more.
Above all, from the viewpoint of storage stability, it is preferable to contain at least one type of organic peroxide.

Examples of the organic peroxide include ketone peroxides such as methyl ethyl ketone peroxide and cyclohexanone peroxide; 1,1-di (t-butylperoxy) cyclohexane and 2,2-di (4,5-di (t-)). Butyl peroxy) cyclohexyl) peroxyketal such as propane; p-menthan hydroperoxide, diisopropylbenzene hydroperoxide, 1,1,3,3-tetramethylbutylhydroperoxide, cumenehydroperoxide, t-butylhydro Hydroperoxides such as peroxides; di (2-t-butylperoxyisopropyl) benzene, dicumyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, t-butylkumi Dialkyl peroxides such as ruperoxide, di-t-hexyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexin-3, di-t-butyl peroxide; dibenzoylper Diacyl peroxides such as oxide, di (4-methylbenzoyl) peroxide; peroxydicarbonates such as di-n-propylperoxydicarbonate, diisopropylperoxydicarbonate; and 2,5-dimethyl-2,5- Peroxyesters such as di (benzoylperoxy) hexane, t-hexylperoxybenzoate, t-butylperoxybenzoate, t-butylperoxy2-ethylhexanonate and the like can be mentioned.

Among these, dialkyl peroxide having a phenyl group in the organic peroxide is preferable from the viewpoint of temperature stability in a medium temperature region, and dicumyl peroxide and di (2-t-butylperoxyisopropyl) benzene are preferable. More preferred.

The content of the radical polymerization initiator in the underfill material is not particularly limited. For example, the content of the radical polymerization initiator is preferably 0.1 part by mass to 20 parts by mass with respect to 100 parts by mass of the total radically polymerizable compound, and 0.5 parts by mass to 10 parts by mass from the viewpoint of curability. More preferably, it is by mass. When the content of the radical polymerization initiator is 20 parts by mass or less with respect to 100 parts by mass of the total radical polymerization compound, volatile components are less likely to be generated and the generation of voids in the cured product tends to be suppressed. Further, when the content of the radical polymerization initiator is 0.3 parts by mass or more with respect to 100 parts by mass of the total radical polymerizable compound, the curability tends to be improved.

The 10-hour half-life temperature of the radical polymerization initiator is preferably 90 ° C. to 150 ° C., more preferably 100 ° C. to 140 ° C. from the viewpoint of curability. If the 10-hour half-life temperature of the radical polymerization initiator is 90 ° C. or higher, the underfill material is cured even if the substrate to which the underfill material is supplied is left in a medium temperature region (for example, on the stage of a hot plate). The initiation of the reaction tends to be suppressed. If the 10-hour half-life temperature of the radical polymerization initiator is 150 ° C. or lower, the curing rate of the underfill material tends to increase in a high temperature region (the temperature at which an electronic component and a wiring board are joined via a joint). is there. As a result, the generation of voids tends to be suppressed.

The half-life temperature of the radical polymerization initiator is a value (° C.) calculated by the following formula. The half-life temperature is listed in the commercial catalog and may be referred to.

τ: half-life, C: constant, Ea: activation energy, R: gas constant, T: absolute temperature

In the case of a 10-hour half-life, the absolute temperature at which τ (time factor), which is half the concentration, becomes 50% can be calculated. The concentration is measured by using an iodine titration method.

(C) Specific silane compound In the specific silane compound, a chain hydrocarbon group having 4 to 9 carbon atoms to which a reactive functional group is bonded via an oxygen atom or not via an oxygen atom is bonded to a silicon atom. Has a structure. The number of carbon atoms of the chain hydrocarbon group having 4 to 9 carbon atoms is preferably 5 to 9, and more preferably 6 to 8. As the specific silane compound, one type may be used alone, or two or more types may be used in combination.

In the specific silane compound, the reactive functional group is not particularly limited. Examples thereof include vinyl group, glycidyl group, acryloyl group, methacryloyl group, styryl group, amino group, ureido group, mercapto group, sulfide group and isocyanate group. From the viewpoint of compatibility with the resin used, a vinyl group, a glycidyl group, an acryloyl group and a methacryloyl group are preferable.

In the specific silane compound, the chain hydrocarbon group having 4 to 9 carbon atoms may be branched or may contain an unsaturated bond. Further, the number of reactive functional groups may be one or more, and may have a substituent other than the reactive functional group. When a chain hydrocarbon group having 4 to 9 carbon atoms is branched or has a substituent, the carbon number of the chain hydrocarbon group includes carbon atoms contained in the branched or substituent. The number of is not included.
It is preferable that the chain hydrocarbon group having 4 to 9 carbon atoms has one reactive functional group bonded only to the terminal via an oxygen atom or not via an oxygen atom. Further, it is preferable that the chain hydrocarbon group having 4 to 9 carbon atoms is not branched, does not contain an unsaturated bond, and has no substituent other than the reactive functional group.

Examples of the specific silane compound include compounds represented by the following general formula (I).

In the general formula (I), R ₁ , R ₂ and R ₃ are independently hydrogen atoms, methyl groups, methoxy groups, ethyl groups, ethoxy groups, phenyl groups or phenoxy groups, and R ₄ is independently a vinyl group. , Glysidyl group, glycidyloxy group, acryloyl group, acryloyloxy group, methacryloyl group or methacryloyloxy group, styryl group, amino group, ureido group, mercapto group, sulfide group or isocyanate group, n is 4 to 9. n is preferably 5-9, more preferably 6-8.

In the general formula _(I), R 1, at least one methoxy group of _{R 2} and _{R 3,} preferably an ethoxy group or phenoxy _group, at least two methoxy groups of R 1, _{R 2} and _{R 3,} It is more preferable that it is an ethoxy group or a phenoxy group, and it is further preferable that all of _{R 1} , R ₂ and R _{3 are a methoxy group, an ethoxy group or a phenoxy group.}

The specific silane compound may be synthesized or a commercially available compound may be used. Examples of commercially available specific silane compounds include KBM-1063 (5-hexenyltrimethoxysilane) and KBM-1083 (7-octenyltrimethoxysilane), which are silane coupling agents manufactured by Shin-Etsu Chemical Industry Co., Ltd. Examples thereof include KBM-4803 (8-glycidoxyoctyltrimethoxysilane) and KBM-5803 (8-methacryloyloxyoctyltrimethoxysilane).

The content of the specific silane compound is preferably 0.15% by mass to 3.0% by mass, and more preferably 0.25% by mass to 2.0% by mass in the total amount of the underfill material. When the content of the specific silane compound is 0.25% by mass or more in the total amount of the underfill material, the effect of suppressing the curing reaction in the medium temperature region obtained by the content of the specific silane compound tends to be sufficiently obtained. When the content of the specific silane compound is 3.0% by mass or less in the total amount of the underfill material, an increase in the viscosity of the underfill material is suppressed, and the moldability tends to be sufficiently maintained.

(Arbitrary ingredient)
The underfill material may contain components other than the radically polymerizable compound, the radical polymerization initiator and the specific silane compound, if necessary. Hereinafter, optional components that may be contained in the underfill material will be described.

(Inorganic filler)
The underfill material may contain an inorganic filler. The type of inorganic filler is not particularly limited. For example, silica such as spherical silica and crystalline silica, calcium carbonate, clay, alumina, silicon nitride, silicon carbide, boron nitride, calcium silicate, potassium titanate, aluminum nitride, beryllium, zirconia, zircon, fosterite, steatite, spinel. , Murite, titania, aluminum hydroxide, magnesium hydroxide, zinc borate and zinc molybdate. The state of the inorganic filler is not particularly limited, and examples thereof include particles, powder, beads obtained by spheroidizing these, glass fiber, and the like. From the viewpoint of fluidity and permeability of the underfill material into the fine gaps, spherical silica is preferable. One type of inorganic filler may be used alone, or two or more types may be used in combination. When two or more kinds of inorganic fillers are used in combination, for example, when two or more kinds of inorganic fillers having the same component but different average particle diameters are used, two or more kinds of inorganic fillers having the same average particle diameter but different components are used. In addition, there are cases where two or more kinds of inorganic fillers having different average particle diameters and types are used.

The inorganic filler is preferably treated with a coupling agent from the viewpoint of the reaction suppressing effect in the medium temperature region. Examples of the coupling agent include various silane compounds such as epoxysilane, mercaptosilane, aminosilane, alkylsilane, ureidosilane, and vinylsilane, titanium compounds, aluminum chelate compounds, and aluminum zirconium compounds. Among these, a coupling agent having an unsaturated double bond is preferable, a coupling agent having an acryloyloxy group or an α-substituted acryloyloxy group is more preferable, and a coupling having a group represented by the following general formula (V) is preferable. The agent is more preferred.

In the general formula (V), R ₄ represents a hydrogen atom, a methyl group or an ethyl group, and R ₅ represents an alkylene group having 1 to 30 carbon atoms. The alkylene group represented by R ₅ is preferably 20 or less, more preferably 15 or less.

Examples of the alkylene group having 1 to 30 carbon atoms represented by R ₅ include an aliphatic hydrocarbon group having 1 to 30 carbon atoms, an alicyclic hydrocarbon group having 3 to 30 carbon atoms, and an aliphatic hydrocarbon group. Examples thereof include a combination of a hydrogen group and an alicyclic hydrocarbon group having a total carbon number of 30 or less. The _{alkylene group represented by R 5} may be branched, may contain a double bond, or may have a substituent. When the _{alkyl group represented by R 5} has a substituent, the number of carbon atoms of the alkyl group does not include the number of carbon atoms contained in the substituent. When the _{alkyl group represented by R 5} is branched, the number of carbon atoms contained in the branch shall be included in the carbon number of the alkyl group.

Specific examples of the aliphatic hydrocarbon group having 1 to 30 carbon atoms include a methylene group, an ethylene group, a propylene group, an isopropylene group, an n-butylene group, a sec-butylene group, a t-butylene group and a pentylene group. , Hexylene group, octylene group, decylene group and dodecylene group.

Specific examples of the alicyclic hydrocarbon group having 3 to 30 carbon atoms include a cyclopentylene group, a cyclohexylene group, a cycloheptylene group, a cyclopentenylene group, and a cyclohexenylene group.

When the _{alkylene group represented by R 5} has a substituent, examples of the substituent include an alkoxy group having 1 to 15 carbon atoms, an aryl group having 1 to 15 carbon atoms, and an aryloxy group having 1 to 15 carbon atoms. Examples thereof include a hydroxyl group, an amino group, a halogen atom, a methacryloxy group, a mercapto group, an imino group, a ureido group, and an isocyanate group. When the _{alkylene group represented by R 5} has a substituent, the number of carbon atoms of the alkylene group does not include the number of carbon atoms contained in the substituent.

The coupling agent having a group represented by the general formula (V) is preferably a compound represented by the following general formula (VI).

_{R 4} and _{R 5} in the general formula (VI) are the same meanings as _{R 4} and _{R 5} in the general formula (V). Each of R ₆ independently represents an alkyl group having 1 to 30 carbon atoms, preferably an alkyl group having 1 to 10 carbon atoms, more preferably an alkyl group having 1 to 5 carbon atoms, and a methyl group or an alkyl group. It is more preferably an ethyl group.

Examples of the alkyl group having 1 to 30 carbon atoms represented by R ₆ include an aliphatic hydrocarbon group having 1 to 30 carbon atoms, an alicyclic hydrocarbon group having 3 to 30 carbon atoms, and an aliphatic hydrocarbon group. Examples thereof include a combination of a hydrogen group and an alicyclic hydrocarbon group having a total carbon number of 30 or less. The alkyl group having 1 to 30 carbon atoms may be branched, may contain a double bond, or may have a substituent. When the _{alkyl group represented by R 6} has a substituent, the number of carbon atoms of the alkyl group does not include the number of carbon atoms contained in the substituent. When the _{alkyl group represented by R 6} is branched, the number of carbon atoms contained in the branch shall be included in the carbon number of the alkyl group.

When using an inorganic filler surface-treated with a coupling agent, the inorganic filler surface-treated in advance may be mixed with other components (pretreatment method), or the inorganic filler not surface-treated and the coupling. Surface treatment may be performed by mixing the agent and other components (separate addition method). From the viewpoint of suppressing the initiation of the reaction in the medium temperature region, it is preferable to use an inorganic filler that has been surface-treated before being mixed with other components.

When the surface treatment of the inorganic filler is performed with the coupling agent, the amount of the coupling agent is preferably 0.05% by mass to 5% by mass, preferably 0.1% by mass to 5% by mass, based on the mass ratio of the inorganic filler. More preferably, it is 2.5% by mass. When the amount of the coupling agent is 0.05% by mass or more in terms of mass ratio with respect to the inorganic filler, the adhesiveness with the constituent members of the electronic component tends to be improved, and when it is 5% by mass or less, molding is performed. Properties, void properties and heat resistance in the medium temperature range tend to improve.

The average particle size of the inorganic filler is not particularly limited. For example, it is preferably 5 μm or less, more preferably 3 μm or less, and further preferably 1 μm or less. Further, the average particle size of the inorganic filler is preferably 0.1 μm or more. When the average particle size of the inorganic filler is 5 μm or less, the permeability and fluidity of the underfill material into the fine gaps are improved, voids and unfilling are less likely to occur, and the semiconductor element is connected to the wiring substrate. Inorganic filler is less likely to get caught in the portion, and connection failure tends to be less likely to occur.

In the present specification, the average particle diameter of the inorganic filler is a particle diameter in which the integrated distribution is 50% in the integrated distribution expressed by the cumulative frequency, with the particle diameter as the class and the volume as the frequency using the following method. Means. As a method for measuring the particle size of particles, for example, a method for collectively measuring a large number of particles using an apparatus such as laser diffraction, dynamic light scattering, and small-angle X-ray scattering, an electron microscope, and an interatomic force microscope. There is a method of measuring the particle size of each particle by imaging using the above. Pretreatment to separate particles of 100 μm or larger may be performed before measuring the particles by using methods such as liquid phase centrifugal sedimentation, field flow separation, particle size exclusion chromatography, and hydrodynamic chromatography. When the measurement sample is a cured product, for example, the ash content obtained as a residue after being treated at a high temperature of 800 ° C. or higher in a muffle furnace or the like can be measured by the above method.

The maximum particle size of the inorganic filler is not particularly limited. For example, from the viewpoint of the size of the gap between the semiconductor elements in the electronic component to be crimped, it is preferably 20 μm or less, more preferably 15 μm or less, and further preferably 10 μm or less. When the maximum particle size of the inorganic filler is 20 μm or less, the permeability and fluidity of the underfill material into the fine gaps are improved, voids and unfilling are less likely to occur, and the connection between the electronic component and the wiring board is prevented. Inorganic filler is less likely to get caught in the portion, and connection failure tends to be less likely to occur.

As a method for measuring the maximum particle size of the inorganic filler, for example, a method for collectively measuring a large number of particles using an apparatus such as laser diffraction, dynamic light scattering, and small-angle X-ray scattering, an electron microscope, and an atom. Examples thereof include a method of measuring the particle size of each particle by imaging using an atomic force microscope or the like.

The content of the inorganic filler in the underfill material is not particularly limited. For example, it is preferably 20% by mass or more, more preferably 30% by mass or more, and further preferably 40% by mass or more in the total mass of the underfill material. The content of the inorganic filler is preferably 70% by mass or less in the total mass of the underfill material. When the content of the inorganic filler is 20% by mass or more, the strength of the cured product of the underfill material is improved, and the reliability such as temperature cycle resistance tends to be improved.

As the underfill material, other fillers other than the inorganic filler may be used. The content of the other filler in the total filler is preferably 10% by mass or less, more preferably 5% by mass or less, further preferably 3% by mass or less, and substantially, other It is particularly preferable that the inorganic filler is not contained (0.1% by mass or less).

(Polymerization inhibitor)
The underfill material may contain a polymerization inhibitor. The type of the polymerization inhibitor is not particularly limited, and a known polymerization inhibitor can be used.

When the underfill material contains a polymerization inhibitor, the content rate is not particularly limited. For example, the total amount of the underfill material is preferably 0.05% by mass to 1% by mass, more preferably 0.08% by mass to 0.7% by mass, and 0.1% by mass to 0% by mass. It is more preferably 5% by mass. When the content of the polymerization inhibitor is 0.05% by mass or more, the reaction in the medium temperature region tends to be suppressed, and when it is 1% by mass or less, the radical polymerization reaction in the medium temperature region tends to be less likely to be inhibited. It is in.

(Flexible agent)
The pre-supplied underfill material of the present invention may contain a flexible agent. The type of flexible agent is not particularly limited, and a commonly used underfill material can be used as the underfill material used for manufacturing electronic component devices. Specific examples thereof include rubber products such as acrylic rubber, nitrile rubber and butadiene rubber, and low molecular weight rubber cross-linking agents.

Commercially available rubber products include, for example, "Paraclon RP" series manufactured by Negami Kogyo Co., Ltd., "Staphyroid IM" series and "Staphyroid AC" series manufactured by Ganz Kasei Co., Ltd. Series, "Metabren C / E / W / S / SX / SRX" manufactured by Mitsubishi Rayon Co., Ltd., "LA" series manufactured by Kuraray Co., Ltd., and D51N of "Nano Strength" series manufactured by Alchema Co., Ltd. Be done.

Commercially available low molecular weight rubber cross-linking agents include, for example, "Ricon" series manufactured by SARTOMER Co., Ltd., "poly bd" series, "poly ip" series, "Epol" series and "KRASOL" manufactured by Idemitsu Kosan Co., Ltd. , "NISSO-PB" manufactured by Nippon Soda Co., Ltd. and the like. These may be used alone or in combination of two or more.

When the underfill material contains a flexible agent, the content rate is not particularly limited. For example, it is preferably 1% by mass to 30% by mass, more preferably 1.5% by mass to 25% by mass, and further preferably 2% by mass to 20% by mass in the total amount of the underfill material. preferable. When the content of the flexible agent is 1% by mass or more, the stress reduction tends to be excellent, and when it is 30% by mass or less, the dispensability tends to be excellent.

(Shaking agent)
When the underfill material is liquid at room temperature, it may contain a shaking imparting agent. By containing the shaking-imparting agent in the underfill material that is liquid at room temperature, the generation of voids tends to be suppressed. That is, if the underfill material cannot maintain its shape and flows while being supplied on the substrate, voids are likely to be involved, but the inclusion of the shaking-imparting agent makes it difficult for the underfill material to flow. , Voids tend to be less likely to occur.

The type of the shaking-imparting agent is not particularly limited, and a shaking-imparting agent generally used in organic resin compositions for electronic components can be used. Specifically, for example, a hydrogenated castor oil compound obtained by adding hydrogen to castor oil, a polyethylene oxide compound obtained by oxidizing polyethylene to introduce a polar group, and an amido wax synthesized from a vegetable oil fatty acid and an amine. Examples include compounds, salts of long-chain polyaminoamides with acid polymers, unsaturated polycarboxylic acid polymers, fine powder silica, and crushed silica.

Among the above-mentioned shaking-imparting agents, salts of long-chain polyaminoamide and acid polymer, unsaturated polycarboxylic acid polymer, fine powder silica, and crushed silica are preferable from the viewpoint of handleability, moldability, and reduction of void generation. ..

As a salt of a long-chain polyaminoamide and an acid polymer, for example, ANTI-TERRA-U100 (Big Chemie Japan Co., Ltd., trade name) is available as a commercially available product, and as an unsaturated polycarboxylic acid polymer, for example, BYK-P105 (Big Chemie Japan Co., Ltd., trade name) is available as a commercial product.

The fine powder silica as the shaking imparting agent preferably has an average primary particle diameter of 5 nm to 200 nm, and more preferably 5 nm to 50 nm. Further, those whose surface is treated with silicone oil or a coupling agent may be used. Examples of the fine powder silica include R974 (Japan Aerosil Co., Ltd., trade name) having an average primary particle size of 12 nm and surface-treated with dimethylsilane, and RX200 (Japan) having an average primary particle size of 12 nm and surface-treated with trimethylsilane. Aerosil Co., Ltd. (trade name), RY200 (Japan Aerosil Co., Ltd., trade name) with an average primary particle size of 12 nm and surface treatment with dimethylsiloxane, R202 (Japan) with an average primary particle size of 14 nm and surface treatment with dimethylsiloxane Aerosil Co., Ltd. (trade name), RA200H (Japan Aerosil Co., Ltd., trade name) with an average primary particle size of 12 nm and surface-treated with aminosilane, R805 (Japan Aerosil Co., Ltd.) with an average primary particle size of 12 nm and surface-treated with alkylsilane. Co., Ltd., trade name), R7200 (Japan Aerosil Co., Ltd., trade name) with an average primary particle size of 12 nm and surface treatment with methacrylate, and YA050C- with an average primary particle size of 50 nm and surface treatment with phenylsilane. SP3 (Admatex Co., Ltd., trade name) is available as a commercial product.

The average particle size of the crushed silica as the shaking-imparting agent is preferably 10 nm or less, more preferably 7.5 nm or less, and further preferably 5.5 nm or less. Further, from the viewpoint of dispersibility inside the resin and cohesiveness of the crushed silica itself, the average particle size of the crushed silica is preferably 4.5 nm or more. The surface of the crushed silica treated with silicone oil or a coupling agent may be used. As the crushed silica, for example, MC3000 (Admatex Co., Ltd., trade name) is available as a commercially available product.

(Polymer component)
When the underfill material is solid at 25 ° C., it may contain a polymer component. The type of the polymer component is not particularly limited, and a polymer component generally used in an organic resin composition for an electronic component can be used. Examples of the polymer component include phenoxy resin, polyimide resin, polyamide resin, polycarbodiimide resin, cyanate ester resin, acrylic resin, polyester resin, polyethylene resin, polyether sulfone resin, polyetherimide resin, polyvinyl acetal resin, and urethane resin. And acrylic rubber. Among these, phenoxy resin, polyimide resin, acrylic rubber, cyanate ester resin and polycarbodiimide resin are preferable, and phenoxy resin, polyimide resin and acrylic rubber are more preferable from the viewpoint of excellent heat resistance and film forming property. These polymer components can be used alone or as a mixture or copolymer of two or more kinds. As the polymer component, a commercially available product may be used, or a synthesized product may be used.

The polyimide resin can be obtained, for example, by subjecting tetracarboxylic dianhydride and diamine to a condensation reaction by a known method. More specifically, in an organic solvent, tetracarboxylic dianhydride and diamine are mixed in an equimolar amount (the order of addition of each component is arbitrary), and the reaction temperature is 80 ° C. or lower, preferably 0 ° C. to 60 ° C. Set to and make an additional reaction. The tetracarboxylic dianhydride is preferably recrystallized and purified with acetic anhydride in order to suppress deterioration of various properties of the underfill material.

The glass transition temperature (Tg) of the polymer component is preferably 100 ° C. or lower, and more preferably 85 ° C. or lower, from the viewpoint of excellent adhesiveness of the underfill material. When the Tg is 100 ° C. or lower, the bumps formed on the electronic components, the electrodes formed on the wiring board, the unevenness of the wiring pattern, etc. are easily embedded by the underfill material, and bubbles are less likely to remain and voids are generated. It tends to be difficult. The above Tg was measured using a differential scanning calorimetry device (DSC) (for example, PerkinElmer, DSC-7 type) under the conditions of a sample amount of 10 mg, a heating rate of 10 ° C./min, and a measurement atmosphere: air. Is the value of.

From the viewpoint of improving film formability, the weight average molecular weight of the polymer component is preferably 10,000 or more, more preferably 30,000 or more, further preferably 40,000 or more, and further preferably 50,000 or more in terms of polystyrene. Is particularly preferable. When the weight average molecular weight is 10,000 or more, the film formability and heat resistance tend to be improved.

The content of the polymer component is not particularly limited, but from the viewpoint of maintaining the shape (film shape, etc.) of the underfill material well, when the polymer component is contained with respect to 100 parts by mass of the radically polymerizable compound, 1 It is preferably from 5 parts by mass to 500 parts by mass, more preferably 5 parts by mass to 300 parts by mass, and further preferably 10 parts by mass to 200 parts by mass. When the content of the polymer component is 1 part by mass or more, the effect of improving the film formability tends to be easily obtained, and when it is 500 parts by mass or less, the curability of the underfill material is improved and the adhesive strength is increased. Tends to improve.

(Flux agent)
The underfill material may contain a flux agent. The type of flux agent is not particularly limited, and conventionally used amine salts of hydrohalates and the like can be used. From the viewpoint of electrical properties, for example, compounds having a phenolic hydroxyl group and a carboxyl group such as hydroxybenzoic acid, acid anhydrides containing a carboxy group such as trimellitic acid, avietic acid, adipic acid, ascorbic acid, citric acid, 2 -Organic acids such as furancarboxylic acid and malic acid, compounds containing two or more alcoholic hydroxyl groups in one molecule, organic acid salts such as metal sulfonates and metal carbonylates, and quinolinol derivatives are listed as preferable flux agents. Be done. More preferably, an organic acid or an organic acid salt is used. One type of flux agent may be used alone, or two or more types may be used in combination.

When the underfill material contains a flux agent, the content thereof is not particularly limited. For example, it is preferably 0.1% by mass to 10% by mass, more preferably 0.5% by mass to 5% by mass, based on the total mass of the underfill material. When the content of the flux agent is 0.1% by mass or more, the wettability of the solder is sufficient and the connection resistance tends to be low. When the content of the flux agent is 10% by mass or less, voids are less likely to occur, and reliability such as migration resistance tends to be improved.

(Ion trap agent)
The underfill material may contain an ion trap agent, if necessary, from the viewpoint of further improving moisture resistance and high temperature standing characteristics. The type of the ion trap agent is not particularly limited, and an ion trap agent generally used in an organic resin composition for an electronic component can be used. Specifically, for example, a compound represented by the following general formula (VII) or (VIII) can be mentioned.

Mg _1-x Al _x (OH) ₂ (CO ₃ ) _{x / 2}・ mH ₂ O ・ ・ ・ (VII)
BiO _x (OH) _y (NO ₃ ) _z ... (VIII)

In the general formula (VII), x is 0 <x ≦ 0.5 and m is a positive number.
In the general formula (VIII), x is 0.9 ≦ x ≦ 1.1, y is 0.6 ≦ y ≦ 0.8, and z is 0.2 ≦ z ≦ 0.4.

The above ion trapping agent is available as a commercial product. For example, the compound of the above general formula (VII) is available as DHT-4A (trade name) of Kyowa Chemical Industry Co., Ltd. Further, the compound of the above general formula (VIII) is available as IXE500 (trade name) of Toagosei Co., Ltd.

Examples of ion trapping agents other than the above include hydrous oxides of elements selected from magnesium, aluminum, titanium, zirconium and antimony. As the ion trap agent, one type may be used alone or two or more types may be used in combination.

When the underfill material contains an ion trap agent, the content thereof is preferably 0.1% by mass to 5.0% by mass with respect to the total amount of the radically polymerizable compound contained in the underfill agent. More preferably, it is 1.0% by mass to 3.0% by mass. The average particle size of the ion trap agent is preferably 0.1 μm to 3.0 μm, and the maximum particle size is preferably 10 μm or less.

The average particle size and the maximum particle size of the ion trap agent are measured by the same method as the above-mentioned inorganic filler.

(Surfactant)
When the underfill material is liquid at room temperature, it may contain a surfactant from the viewpoint of further improving the fillet property. The type of surfactant is not particularly limited, and a surfactant generally used in organic resin compositions for electronic parts can be used. Examples of the surfactant include nonionic surfactants. Examples of the nonionic surfactant include a polyoxyalkylene alkyl ether surfactant such as polyoxyethylene alkyl ether, a sorbitan fatty acid ester surfactant, a polyoxyethylene sorbitan fatty acid ester surfactant, and a polyoxyethylene sorbitol fatty acid. Ester surfactants, glycerin fatty acid ester surfactants, polyoxyethylene fatty acid ester surfactants, polyoxyethylene alkylamine surfactants, alkylalkanolamide surfactants, polyether-modified silicone surfactants, aralkyl-modified silicone surfactants Agents, polyester-modified silicone surfactants, and polyacrylic surfactants. From the viewpoint of reducing the surface tension of the underfill material, a polyether-modified silicone surfactant and an aralkyl-modified silicone surfactant are preferable.

As the surfactant, for example, BYK-307, BYK-333, BYK-377 and BYK-323 (Big Chemie Japan Co., Ltd., trade name) are available as commercial products.

In addition to the above-mentioned surfactant, a silicone-modified epoxy resin can also be used as the surfactant. The silicone-modified epoxy resin can be obtained as a reaction product of an organosiloxane having a functional group that reacts with an epoxy group and an epoxy resin. The silicone-modified epoxy resin is preferably liquid at room temperature. Examples of the organosiloxane having a functional group that reacts with an epoxy group include dimethylsiloxane, diphenylsiloxane and methylphenylsiloxane having at least one amino group, carboxy group, hydroxyl group, phenolic hydroxyl group, mercapto group and the like in one molecule. Can be mentioned. These organosiloxanes are, for example, BY16-799, BY16-871 and BY16-004 (Tole Dow Corning Co., Ltd., trade name), and X-22-1821 and KF-8010 (Shin-Etsu Chemical Co., Ltd., trade name). ) Is available as a commercial product.

The weight average molecular weight of the organosiloxane measured by GPC (gel permeation chromatography) is preferably in the range of 500 to 5000, and more preferably in the range of 1000 to 3000. When the weight average molecular weight is 500 or more, it is suppressed that the compatibility with the resin is excessively improved, and the effect as an additive tends to be more easily exhibited. When the weight average molecular weight is 5000 or less, the decrease in compatibility with the resin is suppressed, separation and exudation of the silicone-modified epoxy resin from the cured product are unlikely to occur, and the adhesiveness and appearance are less likely to be impaired. ..

The epoxy resin used to obtain the silicone-modified epoxy resin is not particularly limited as long as it is compatible with the underfill material, and an epoxy resin generally used in organic resin compositions for electronic parts should be used. Can be done. Specifically, for example, a glycidyl ether type epoxy resin obtained by reacting bisphenol A, bisphenol F, bisphenol AD, bisphenol S, naphthalenediol, hydrogenated bisphenol A and the like with epichlorohydrin; orthocresol novolac type epoxy resin and the like. A novolak type epoxy resin obtained by epoxidizing a novolak resin obtained by condensing or cocondensing a phenol compound and an aldehyde compound; a glycidyl ester type epoxy resin obtained by reacting a polybasic acid such as phthalic acid or dimer acid with epichlorohydrin; A glycidylamine type epoxy resin obtained by reacting a polyamine such as diaminodiphenylmethane or isocyanuric acid with epichlorohydrin; and a linear aliphatic epoxy resin and an alicyclic epoxy obtained by oxidizing an olefin bond with a peracid such as peracetic acid. Resin is mentioned. These types may be used alone or in combination of two or more. The epoxy resin used to obtain the silicone-modified epoxy resin is preferably liquid at room temperature.

(Silane compounds other than specific silane compounds)
The underfill material may contain a silane compound other than the specific silane compound. Examples of such a silane compound include those that do not correspond to the specific silane compound among the silane compounds commercially available as silane coupling agents.

Examples of the silane coupling agent include aminosilane coupling agent, epoxysilane coupling agent, ureidosilane coupling agent, isocyanatesilane coupling agent, vinylsilane coupling agent, acrylicsilane coupling agent, methacrylsilane coupling agent and ketimine. Examples thereof include silane coupling agents, and isocyanate silane coupling agents, acrylic silane coupling agents, methacrylic silane silane coupling agents and epoxy silane coupling agents are preferable. These silane coupling agents can be purchased from Toray Dow Corning Co., Ltd., Shin-Etsu Chemical Co., Ltd., Matsumoto Fine Chemical Co., Ltd., Tokyo Chemical Industry Co., Ltd., and the like.

When the underfill material contains a silane coupling agent, the content thereof is not particularly limited. For example, the total content of the specific silane coupling agent and other silane coupling agents can be 0% by mass to 10% by mass in the total amount of the underfill material, and is 0% by mass to 5% by mass. Is preferable. When the content is 10% by mass or less, the silane coupling agent is less likely to be vaporized due to the heat at the time of mounting, and voids are less likely to be generated.

(Other ingredients)
As the underfill material, dyes, colorants such as carbon black, diluents and the like can be used as other additives, if necessary.

(Physical characteristics)
The fluctuation index of the underfill material is preferably 1.0 or more, more preferably 1.5 or more, and further preferably 2.0 or more.

The fluctuation index of the underfill material is (viscosity at a shear rate of ^{0.5s -1 ) / (5.0s −} ) when the viscosity of the underfill material maintained at 25 ° C. is measured using a rheometer. The value is (viscosity at a shear rate of ^1). Viscosity at a shear rate of 0.5 s ^-1 and viscosity at a shear rate of 5.0 s ^-1 are measured using a rotary shear viscometer equipped with a cone plate (diameter 40 mm, cone angle 0 °). The value is measured at 25 ° C.

When the underfill material is liquid at 25 ° C, the viscosity of the underfill material at 25 ° C is preferably 10 Pa · s to 150 Pa · s, more preferably 20 Pa · s to 130 Pa · s, and 30 Pa · s. -It is more preferably s to 110 Pa · s.
The viscosity in the medium temperature region of about 50 ° C. to 100 ° C. is preferably 0.1 Pa · s to 20 Pa · s, more preferably 0.5 Pa · s to 15 Pa · s, and 1 Pa · s to 10 Pa · s. It is more preferably s.
The viscosity in the high temperature region during curing is preferably 0.1 Pa · s to 10 Pa · s, more preferably 0.3 Pa · s to 8 Pa · s, and 0.5 Pa · s to 5 Pa · s. Is more preferable.

<Manufacturing method of underfill material>
(Manufacturing method of underfill material that is liquid at room temperature)
The method for producing an underfill material that is liquid at room temperature is not particularly limited. For example, a liquid underfill material can be produced at room temperature by weighing a predetermined component, mixing and kneading it using a raker, a mixing roll, a planetary mixer, or the like, and defoaming if necessary. ..

(Manufacturing method of underfill material solid at room temperature)
The method for producing an underfill material that is solid at room temperature is not particularly limited. For example, when the underfill material solid at room temperature is in the form of a film, a predetermined component is first weighed, dissolved or dispersed by stirring and mixing, kneading, etc. to prepare a resin varnish, and the resin varnish is demolded. It can be produced by applying a knife coater, a roll coater, an applicator or the like on the base film to which the above-mentioned material has been applied, and removing the organic solvent by heating.

The organic solvent used for preparing the resin varnish preferably has a property of uniformly dissolving or dispersing each component. Examples include dimethylformamide, dimethylacetamide, N-methyl-2-pyrrolidone, dimethyl sulfoxide, diethylene glycol dimethyl ether, toluene, benzene, xylene, methyl ethyl ketone, tetrahydrofuran, ethyl cellosolve, ethyl cellosolve acetate, butyl cellosolve, dioxane, cyclohexanone, and ethyl acetate. Be done. These organic solvents can be used alone or in combination of two or more. Stirring and mixing or kneading in the preparation of the resin varnish can be carried out by using, for example, a stirrer, a raft machine, a triple roll, a ball mill, a bead mill or a homodisper.

The base film is not particularly limited as long as it has heat resistance that can withstand the heating conditions when volatilizing the organic solvent. For example, a polyolefin film such as a polypropylene film and a polymethylpentene film, a polyester film such as a polyethylene terephthalate film and a polyethylene naphthalate film, a polyimide film and a polyetherimide film can be exemplified. The base film may be a single-layer film or a multilayer film. In the case of a multilayer film, each layer may be made of different materials or may be made of the same material.

The drying conditions for volatilizing the organic solvent from the resin varnish coated on the base film are preferably conditions in which the organic solvent is sufficiently volatilized. Specifically, for example, it can be carried out at 50 ° C. to 200 ° C. for 0.1 minutes to 90 minutes.

<Electronic component equipment>
The electronic component device of the present embodiment includes the cured product of the pre-supplied underfill material described above.
In one embodiment, the electronic component device comprises an electronic component and a wiring board that is arranged to face the electronic component and is electrically joined to the electronic component via a junction, said pre-supplied. The cured product of the mold underfill material has a structure arranged between the electronic component and the wiring board.

Examples of electronic component devices include lead frames, pre-wired tape carriers, rigid and flexible wiring boards, glass, support members (wiring substrates) such as silicon wafers, and active elements such as semiconductor chips, transistors, diodes, and thyristors. Examples thereof include electronic component devices obtained by mounting electronic components such as passive elements such as capacitors, resistors, resistance arrays, coils, and switches, and sealing the necessary parts with an underfill material.

The underfill material of the present embodiment is particularly suitable as an underfill material for flip-chip bonding, which requires high reliability. Therefore, a preferred embodiment of the electronic component device of the present embodiment is an electronic component device in which a semiconductor element is flip-chip bonded by bump connection to a wiring formed on a rigid or flexible wiring board or a glass plate. Specific examples thereof include electronic component devices of flip chip BGA (Ball Grid Array), LGA (Land Grid Array) and COF (Chip On Film).

In the field of flip chips in which the underfill material of the present embodiment is particularly suitable, a lead-free solder such as Sn-Ag-Cu is used as the bump material of the connecting portion connecting the wiring board and the semiconductor element of the electronic component. Examples include flip-chip semiconductor devices. By using the underfill material of the present embodiment, good reliability can be maintained even for a flip chip having a bump connection made of lead-free solder, which is physically fragile as compared with conventional lead solder.

<Manufacturing method of electronic component equipment>
The method for manufacturing an electronic component device according to the present embodiment is a method for manufacturing an electronic component device that manufactures an electronic component device by electrically joining the electronic component and a wiring board via a joint portion.
A supply step of supplying the above-mentioned pre-supply type underfill material to at least one surface of the electronic component on the side facing the wiring board or the surface of the wiring board facing the electronic component.
It includes a joining step of joining the electronic component and the wiring board via a joining portion and curing the pre-supplied underfill material.

In the supply step of the above method, when the underfill material is a liquid, the underfill material is supplied by coating. When the underfill material is in the form of a film, the film-like underfill material is supplied by sticking. Further, in the joining step, the joining of the electronic component and the wiring board may be performed together with the curing of the underfill material.

In certain embodiments, the method of manufacturing an electronic component device comprises the following steps:
(1) Supply step of supplying an underfill material to at least one of the surface of the electronic component facing the wiring board or the surface of the wiring board facing the electronic component (2) The electronic component and the wiring board By pressing and facing each other through the metal bump of the connection portion, the gap between the electronic component and the wiring board is filled with an underfill material, and the electronic component and the wiring board are connected to each other. Pressurization step of contacting through the metal bump of the portion (3) At least one of the pressurization step and after the pressurization step, the electronic component and the wiring board are applied via the metal bump of the connection portion. A joining step (heat treatment step) in which the electronic component and the wiring board are joined via a metal bump of the connecting portion and the underfill material is cured by heat treatment in a state of pressure contact.

Hereinafter, a method of manufacturing an electronic component device by a pre-supply method will be described with reference to the drawings, but the present invention is not limited thereto. Further, the size of the members in each figure is conceptual, and the relative relationship between the sizes of the members is not limited to this.
FIG. 1 is a cross-sectional view schematically showing a process of a method of manufacturing an electronic component device by a pre-supply method using a pre-supply type underfill material which is liquid at room temperature. In the method of manufacturing the electronic component device of FIG. 1, a mode in which the pre-supplied underfill material is attached to the surface of the wiring board facing the electronic component will be described. Further, the metal bump is provided on the electronic component side, and the electronic component and the wiring board are joined via the metal bump. However, the present invention is not limited to these aspects.

In FIG. 1, 1 is a semiconductor chip (electronic component), 2 is a solder bump (metal bump), 3 is a connection pad, 4 is a solder resist, 5 is a wiring board, and 6 is an underfill material.

First, in FIG. 1A, the underfill material 6 is applied to the surface of the wiring board 5 on the side where the connection pad 3 is provided (the side of the wiring board 5 facing the semiconductor chip 1) (supply step). Examples of the method of applying the underfill material 6 include a dispensing method, a casting method, and a printing method. The underfill material 6 may be applied to the entire area of the wiring board 5 provided with the connection pad 3, or may be applied to a part of the area of the wiring board 5 provided with the connection pad 3. By applying the underfill material 6 to a part of the region provided with the connection pad 3 of the wiring board 5, the underfill material 6 is formed when the wiring board 5 and the semiconductor chip 1 are brought into contact with each other via the solder bumps 2. It is preferable because it flows and fills the gap between the wiring board 5 and the semiconductor chip 1. As the pattern of applying the underfill material 6 to the wiring board 5, a cross type or a double cross type along the diagonal line of the region where the semiconductor chip 1 of the wiring board 5 is arranged is preferable.

Next, in FIG. 1B, the semiconductor chip 1 and the wiring board 5 are opposed to each other while being pressurized via the solder bumps 2, so that the gap between the semiconductor chip 1 and the wiring board 5 is formed by the underfill material 6. It is filled and the semiconductor chip 1 and the connection pad 3 of the wiring board 5 are brought into contact with each other via the solder bump 2 (pressurization step).

As a pressurizing condition for filling the gap between the semiconductor chip 1 and the wiring board 5 with the underfill material 6, the weight applied per bump is preferably 0.001N to 100N, preferably 0.005N to 50N. Is more preferable, and 0.01N to 10N is further preferable.

Further, as a pressurizing condition when the semiconductor chip 1 and the connection pad 3 of the wiring board 5 are brought into contact with each other via the solder bumps 2, the weight applied per bump is preferably 0.002N to 200N. It is more preferably 0.01N to 100N, and even more preferably 0.02N to 20N. Under this pressurized condition, the semiconductor chip 1 and the connection pad 3 of the wiring board 5 may be joined via the solder bump 2 in the heat treatment step described later.

During the pressurizing step and at least one after the pressurizing step, the semiconductor chip 1 and the connection pad 3 of the wiring board 5 are pressed and contacted with each other via the solder bumps 2 and heat-treated to form the semiconductor chip 1. The connection pad 3 of the wiring board 5 is joined via the solder bump 2 and the underfill material 6 is cured (heat treatment step).

The temperature of the heat treatment is preferably 150 ° C. to 350 ° C., more preferably 220 ° C. to 300 ° C., and even more preferably 240 ° C. to 270 ° C. By this heat treatment, the underfill material 6 is cured.

Further, if necessary, in order to sufficiently cure the underfill material 6, heat treatment may be performed in the range of 120 ° C. to 200 ° C. for 0.5 hours to 6 hours.

By going through the above steps, the electronic component device of the present embodiment is manufactured.

FIG. 2 is a cross-sectional view schematically showing a process of a method of manufacturing an electronic component device by a pre-supply method using a solid and film-like underfill material at room temperature.

First, as shown in FIG. 2A, a solder resist 60 having an opening at a position where the connection bump 30 is formed is formed on the substrate 20 having the wiring 15. Further, a connection bump 30 is formed in the opening of the solder resist 60. Although it is not always necessary to provide the solder resist 60, by providing the solder resist on the substrate 20, it is possible to suppress the occurrence of a bridge between the wirings 15 and improve the connection reliability and the insulation reliability. The solder resist 60 can be formed, for example, by using a commercially available ink for a solder resist for packaging. Specific examples of commercially available package solder resist inks include SR series (manufactured by Hitachi Kasei Co., Ltd., trade name) and PSR4000-AUS series (manufactured by Taiyo Ink Mfg. Co., Ltd., trade name).

Next, as shown in FIG. 2B, a film-like underfill material (hereinafter, sometimes referred to as “film-like underfill material”) is placed on the substrate 20 on which the connection bump 30 and the solder resist 60 are formed. 40 is pasted. The film-like underfill material 40 can be attached by, for example, heat pressing, roll laminating, or vacuum laminating. The supply area and thickness of the film-shaped underfill material 40 are appropriately set according to the sizes of the semiconductor chip (electronic component) 10 and the substrate 20 and the height of the connection bumps 30.

After the film-shaped underfill material 40 is attached to the substrate 20, the semiconductor chip 10 is arranged so that the wiring 15 faces the substrate 20. At this time, the wiring 15 of the semiconductor chip 10 and the connection bump 30 are aligned by using a connection device such as a flip chip bonder. Subsequently, the semiconductor chip 10 and the substrate 20 are crimped while being heated at a temperature equal to or higher than the melting point of the connecting bump 30, and as shown in FIG. 2C, the semiconductor chip 10 and the substrate 20 are pressed via the connecting bump 30. Connecting. At this time, the film-like underfill material 40 fills the gap between the semiconductor chip 10 and the substrate 20. From the above, the electronic component device 600 is obtained.

In the method for manufacturing an electronic component device of the present embodiment, the connection bumps 30 are melted and semiconductors are temporarily fixed after alignment (in a state where an electronic component adhesive is used) and heat-treated in a reflow furnace. The chip 10 and the substrate 20 may be connected. Since it is not always necessary to form a metal joint at the stage of temporary fixing, crimping can be performed with a lower load, a short time, and a lower temperature as compared with the above-mentioned method of crimping while heating. Therefore, the productivity tends to be improved and the deterioration of the connecting portion tends to be suppressed.

Further, after connecting the semiconductor chip 10 and the substrate 20, heat treatment may be performed in an oven or the like to further improve the connection reliability and the insulation reliability. The heat treatment is preferably performed at a temperature at which the underfill material is cured, and more preferably at a temperature at which the underfill material is completely cured. The temperature and time of the heat treatment can be appropriately set, and suitable conditions are the same as for the underfill material which is liquid at room temperature.

Next, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

(Making underfill material)
The following components are blended in the amounts (unit: parts by mass) shown in Tables 1 and 2, respectively, kneaded and dispersed with a three-roll machine and a raft machine, and then vacuum defoamed to under the examples and comparative examples. A fill material was prepared. "-" In the table means that the corresponding component is not contained. All of the prepared underfill materials were liquid at 25 ° C. Of the silane compounds 1 to 7, silane compounds 1 to 4 correspond to specific silane compounds, and silane compounds 5 to 7 do not correspond to specific silane compounds.

-Radical polymerizable compound 1: A-DCP (manufactured by Shin Nakamura Chemical Industry Co., Ltd., tricyclodecanedimethanol diacrylate, functional group equivalent: 152 g / eq)
-Radical polymerizable compound 2: ABE-300 (manufactured by Shin-Nakamura Chemical Industry Co., Ltd., ethoxylated bisphenol A diacrylate, functional group equivalent: 233 g / eq)
-Radical polymerizable compound 3: UA-13 (manufactured by Shin Nakamura Chemical Industry Co., Ltd., urethane acrylate, functional group equivalent: 744 g / eq)
-Radical polymerizable compound 4: HOA-MPE (N) (manufactured by Kyoeisha Chemical Co., Ltd., 2-acryloyloxyethyl-2-hydroxyethylphthalic acid, functional group equivalent: 292 g / eq)
-Silane compound 1: KBM-1063 (5-hexenyltrimethoxysilane manufactured by Shin-Etsu Chemical Co., Ltd.)
-Silane compound 2: KBM-1083 (7-octenyltrimethoxysilane manufactured by Shin-Etsu Chemical Co., Ltd.)
-Silane compound 3: KBM-4803 (manufactured by Shin-Etsu Chemical Co., Ltd., 8-glycidoxyoctyltrimethoxysilane)
-Silane compound 4: KBM-5803 (manufactured by Shin-Etsu Chemical Co., Ltd., 8-methacryloyloxyoctyltrimethoxysilane)
-Silane compound 5: KBM-503 (manufactured by Shin-Etsu Chemical Co., Ltd., 3-methacryloyloxypropyltrimethoxysilane)
-Silane compound 6: KBM-403 (manufactured by Shin-Etsu Chemical Co., Ltd., 3-glycidoxypropyltrimethoxysilane)
Silane compound 7: KBM-1003 (manufactured by Shin-Etsu Chemical Co., Ltd., vinyltrimethoxysilane)
-Radical polymerization initiator: Perkadox BC-FF (manufactured by Kayaku Akzo Corporation, dicumyl peroxide)
-Flexible agent: Nanostrength D51N (manufactured by Arkema Co., Ltd., modified polymethylmethacrylate-polybutylacrylate block copolymer, weight average molecular weight: 57,000)
Polymerization inhibitor: SUMIRIZER GM (manufactured by Sumitomo Chemical Co., Ltd., 2-t-butyl-6- (3-butyl-2-hydroxy-5-methylbenzyl) -4-methylphenylacrylate)
-Flux agent: Adipic acid (manufactured by Asahi Kasei Chemicals Co., Ltd.)
-Shaking agent: R805 (manufactured by Nippon Aerosil Co., Ltd., powdered silica with a volume average particle diameter of 12 nm)
-Inorganic filler: SE-2050-SMJ (manufactured by Admatex Co., Ltd., volume average particle diameter 0.5 μm, maximum particle diameter 5 μm, methacrylate silane coupling treatment (with a silane coupling agent having a 3-methacryloxypropyl group) Processed) spherical silica)

(Evaluation)
Electronic component devices were manufactured using the underfill materials prepared in Examples and Comparative Examples, and the state of void generation was evaluated by the tests shown below. The evaluation results are shown in Tables 3 and 4.

An underfill material was applied to the chip mounting portion of the wiring board using a dispenser (needle diameter 0.3 mm) in a cloth shape, and another cloth shape was applied so as to be overlapped with a 45 ° shift (total coating amount:). About 3 mg). Next, a wiring board coated with an underfill material was placed on a stage of a hot plate heated to 70 ° C. and left for 5 minutes, 30 minutes, 60 minutes or 90 minutes. After that, the chip is mounted on the wiring board, thermocompression bonding is performed under the conditions of load: 7.5 N, temperature / time: 260 ° C./5 seconds, and then the semiconductor device is cured under the conditions of 175 ° C. for 1 hour. Got

The wiring board used for manufacturing the electronic component device has a size of 14 mm in length, 14 mm in width, and 0.30 mm in thickness, the core layer is E-679FG (Hitachi Kasei Co., Ltd., trade name), and the solder resist is AUS-. It was 308 (Taiyo Holdings Co., Ltd., trade name), and the substrate plating was laminated in the order of Ni (5.0 μm), Pd (0.30 μm), and Au (0.35 μm).
The chip used to manufacture the electronic component device has a size of 7.3 mm in length, 7.3 mm in width, and 0.15 mm in thickness, and has bumps of copper (height 30 μm) and solder (material: SnAg, height: 15 μm). The bump pitch was 80 μm and the number of bumps was 328.

The manufactured electronic component device was observed using an ultrasonic flaw detector (AT-5500, Hitachi Construction Machinery Co., Ltd., trade name), and the void occupancy rate was evaluated according to the following criteria.
A: Void area is 1% or less of the total area B: Void area is more than 1% of the total area and 5% or less C: Void area is more than 5% of the total area and 20% or less D: Void area is 20% of the total area Over%

As is clear from the evaluation results, the electronic component device of the example manufactured by using the underfill material containing the specific silane compound has a small void occupancy even when the hot plate is left on the stage for a long time. It was. Therefore, it can be seen that the underfill material of the example is excellent in voidlessness and stage stability.

On the other hand, the electronic component device of the comparative example produced by using the underfill material containing the silane compound which does not correspond to the specific silane compound has a small void occupancy when the hot plate is left on the stage for a short time. The void occupancy rate increased as the standing time increased.

In the above embodiment, a liquid underfill material was used at 25 ° C., but the same effect can be obtained when a solid underfill material is used at 25 ° C.

1 Semiconductor chip (electronic component)
2 Solder bump 3 Connection pad 4 Solder resist 5 Wiring board 6 Underfill material 10 Semiconductor chip (electronic component)
15 Wiring 20 Board 30 Connection bump 40 Film-like underfill material 60 Solder resist 600 Electronic component equipment

Claims (9)

It contains (A) a radically polymerizable compound, (B) a radical polymerization initiator, (C) a silane compound represented by the following general formula (I), and an inorganic filler treated with a coupling agent . Pre-supplied underfill material.

[In general formula (I), R ₁ , R ₂ and R ₃ are independent methoxy groups, and R ₄ is a vinyl group, a glycidyl group, a glycidyloxy group, an acryloyl group, an acryloyloxy group, a methacryloyl group or a methacryloyloxy group. It is a group, and n is 4 to 9. ] The pre-supplied underfill material according to claim 1, wherein the inorganic filler is silica. The pre-supplied underfill material according to claim 1 or 2, wherein the coupling agent has an unsaturated double bond. The pre-supplied underfill material according to any one of claims 1 to 3, wherein the coupling agent has a group represented by the following general formula (V).

In the general formula (V), R ₄ represents a hydrogen atom, a methyl group or an ethyl group, and R ₅ represents an alkylene group having 1 to 30 carbon atoms. The pre-supplied underfill material according to any one of claims 1 to 4, further comprising a flexible agent. The cured product of the pre-supplied underfill material according to any one of claims 1 to 5. An electronic component device comprising a cured product of the pre-supplied underfill material according to claim 6. The cured product of the pre-supplied underfill material has an electronic component and a wiring board that is arranged to face the electronic component and is electrically joined to the electronic component via a joint portion. The electronic component device according to claim 7, which is arranged between the electronic component and the wiring board. It is a manufacturing method of an electronic component device that manufactures an electronic component device by electrically joining an electronic component and a wiring board via a joint.
The aspect according to any one of claims 1 to 5, wherein the surface of the electronic component facing the wiring board or at least one surface of the wiring board facing the electronic component. The supply process for supplying pre-supplied underfill material and
A method for manufacturing an electronic component device, which comprises a joining step of joining the electronic component and the wiring board via a joining portion and curing the pre-supplied underfill material.