JP6638380B2 - Pre-supply type underfill material and cured product thereof, electronic component device and method of manufacturing the same - Google Patents

Description

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

  2. Description of the Related Art Conventionally, as a technology for sealing elements of an electronic component device such as a transistor, an IC (Integrated Circuit), and an LSI (Large-scale Integration), sealing with a resin has been the mainstream in terms of productivity, cost, and the like. Epoxy resins are widely used as resins for this. This is because the epoxy resin balances various properties such as workability, moldability, electrical properties, moisture resistance, heat resistance, mechanical properties, and adhesiveness to an insert product.

  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). Also, in an electronic component device (flip chip) in which a semiconductor element is directly bump-connected to a wiring board having ceramic, glass / epoxy resin, glass / imide resin, polyimide film or the like as a substrate, the semiconductor element bump-connected. An epoxy resin composition that is liquid at room temperature is used as an underfill material that fills a gap between the substrate and the wiring board.

  In the bare chip mounting, since the circuit formation surface is not sufficiently protected, moisture and ionic impurities easily enter. In flip-chip mounting, since the semiconductor element and the wiring board have different coefficients of thermal expansion, thermal stress is likely to be generated at the connection portion. Therefore, the epoxy resin composition plays an important role in protecting electronic components from temperature, humidity, or mechanical external force.

  As an 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 an imidazole compound as a curing accelerator for an epoxy resin obtained by covering the periphery of the imidazole compound with a coating of a thermosetting resin. An epoxy resin composition using at least one of microsphere particles or amine adduct particles obtained (for example, see Patent Document 2) has been reported.

  As a method of filling the underfill material, a metal element is bonded to the wiring board by a method such as reflow, and then the gap between the semiconductor element and the wiring board is formed at room temperature by using a capillary phenomenon. A capillary underfill method (post-supply method) in which a liquid epoxy resin composition is permeated with a liquid is generally used. In this method, if the gap is narrow, the filling is likely to be insufficient, and voids may be easily generated. As a result, there is a concern that after the semiconductor element and the wiring board are joined, stress is generated due to a volume change during cooling, and the joint is likely to be broken.

  Therefore, before joining the semiconductor element and the wiring substrate, a liquid or solid (film-like or the like) underfill material is supplied onto the wiring substrate, and the semiconductor element having the metal bumps is thermocompression-bonded to the semiconductor element and the wiring. A pre-supply system has been devised in which the bonding with the substrate and the curing reaction of the underfill material are performed at once. The pre-supply method has a feature that the underfill material is hardened at the time of joining and the joint is immediately protected, so that it is easy to cope with a narrow pitch.

Japanese Patent Publication No. 7-53794 Japanese Patent No. 3446730

If a conventional epoxy resin composition is to be used as a pre-supply type underfill material, the following problem is encountered.
The epoxy resin composition contains an epoxy resin and at least one of a curing catalyst and a curing agent. When heat is applied, a ring-opening polymerization reaction of an epoxy group occurs to increase the molecular weight. Therefore, the epoxy resin composition requires some time to cure. In particular, in the case of the pre-supply method, the underfill material is supplied to a wiring board or an electronic component heated by a hot plate in a medium temperature range of about 50 ° C. to 100 ° C. Therefore, if it takes a long time to cure, voids tend to be generated due to moisture, volatile compounds, and the like adhering to wiring boards, electronic components, and the like. The 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 speed of the underfill material and suppressing the generation of voids. However, even in the case of an underfill material whose reaction mechanism is a radical polymerization reaction, as in the case of an epoxy resin, the reaction in a middle temperature region gradually progresses and the viscosity increases, so that entrapment voids may be generated. In particular, in the pre-supply system, the underfill material may be held on the hot plate for a long time depending on the form of the package (PKG). Therefore, a property that the generation of voids in the cured product is suppressed even when the cured product is left in a medium temperature region is required for a pre-supply type underfill material.

  The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a pre-supply type underfill material in which the generation of voids in a cured product is suppressed even when left in a medium temperature region, a cured product thereof, and an electronic component device and a method of manufacturing the same. Make it an issue.

Means for solving the above problems include the following embodiments.
<1> (A) a radically polymerizable compound, (B) a radical polymerization initiator, and (C) a reactive functional group having 4 to 9 carbon atoms bonded via an oxygen atom or not via an oxygen atom. And a silane compound having a structure in which a chain hydrocarbon group 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 pre-supply type underfill material according to <1> or <2>, wherein the silane compound is represented by the following general formula (I).

[In the general formula (I), R ₁ , R ₂ and R ₃ are each independently a hydrogen atom, a methyl group, a methoxy group, an ethyl group, an ethoxy group, a phenyl group or a phenoxy group, and R ₄ is a vinyl group, glycidyl. Group, glycidyloxy group, acryloyl group, acryloyloxy group, methacryloyl group, methacryloyloxy group, styryl group, amino group, ureido group, mercapto group, sulfide group or isocyanate group, and n is 4 to 9. ]
<4> The pre-supply type underfill material according to any one of <1> to <3>, further including an inorganic filler.
<5> The pre-supply type underfill material according to any one of <1> to <4>, further comprising a flexible agent.
<6> A cured product of the pre-supply type underfill material according to any one of <1> to <5>.
<7> An electronic component device including a cured product of the pre-supply type underfill material according to <6>.
<8> a cured product of the pre-supply type underfill material, comprising: an electronic component; and a wiring board arranged to face the electronic component and electrically connected to the electronic component via a bonding portion. Is an electronic component device according to <7>, which is disposed between the electronic component and the wiring board.
<9> A method for manufacturing an electronic component device, wherein the electronic component and the wiring board are electrically connected to each other via a bonding portion to manufacture the electronic component device.
The surface according to any one of <1> to <5>, on a surface of the electronic component facing the wiring substrate or at least one of a surface of the wiring substrate facing the electronic component. A supply step of supplying a pre-supply type underfill material,
A bonding step of bonding the electronic component and the wiring board via a bonding portion and curing the pre-supply type underfill material.

  ADVANTAGE OF THE INVENTION According to this invention, the supply of the underfill material which suppresses generation | occurrence | production of the void in a hardened | cured material even if it is left in the middle temperature area | region, its hardened | cured material, an electronic component device, and its manufacturing method are provided.

It is sectional drawing explaining the process of the manufacturing method of the electronic component device using the underfill material of the liquid supply at 25 degreeC. It is sectional drawing explaining the process of the manufacturing method of the electronic component device using the film-form 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 constituent elements (including element steps and the like) are not essential unless otherwise specified, and unless it is deemed essential in principle. The same applies to numerical values and their ranges, and does not limit the present invention.
In this specification, the term "step" includes, in addition to a step independent of other steps, even if the purpose of the step is achieved even if it cannot be clearly distinguished from the other steps, the step is also included. It is.
In the present specification, the numerical value range indicated by using “to” includes the numerical value described before and after “to” as the minimum value and the maximum value, respectively.
In the present specification, the content of each component in the underfill material is, if there are a plurality of types of substances corresponding to each component in the underfill material, unless otherwise specified, the plurality of types of materials present in the underfill material. It means the total content of the substance.
In the present specification, the particle diameter of each component in the underfill material is, when there are a plurality of types of particles corresponding to each component in the underfill material, unless otherwise specified, the plurality of types of particles present in the underfill material. Mean value for a mixture of particles.
In this specification, (meth) acrylate means acrylate or methacrylate, and (meth) acryloyl means acryloyl or methacryloyl.
In this specification, the term "layer" refers to a case where a layer is formed only on a part of the region in addition to a case where the layer is formed on the entire region when the region where the layer is present is observed. Is also included.

<Pre-supply type underfill material>
The pre-supply type underfill material of the present embodiment (hereinafter, also simply referred to as the underfill material) includes (A) a radical polymerizable compound, (B) a radical polymerization initiator, and (C) a reactive functional group containing oxygen. A silane compound having a structure in which a chain hydrocarbon group having 4 to 9 carbon atoms bonded via 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 rate of the curing reaction in a high-temperature region is higher than that of the underfill material whose reaction mechanism is an epoxy ring-opening reaction. Further, the present inventors have made it clear that the progress of the curing reaction in a medium temperature region is suppressed by including the specific silane compound in the underfill material. Although the reason is not clear, it is considered that the specific silane compound has high wettability with respect to a radical polymerizable compound such as a (meth) acrylate compound contained in the underfill material, has excellent compatibility, and improves thermal stability. . Furthermore, since the specific silane compound has a long-chain alkyl group, the surface tension is small, and it tends to gather on the surface of the underfill material before curing (the part in contact with the outside air), and the surface of the underfill material is coated with the specific silane compound. In such a state, it is considered that the curing reaction is suppressed even when left for a long time in the medium temperature region.

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 the viscosity is 0.0001 Pa · s to 1000 Pa at 25 ° C. Means a substance that is s As used herein, the term “viscosity” refers to the viscosity of an underfill material maintained at 25 ° C., which is measured using a rotary shear viscometer equipped with a cone plate (diameter 40 mm, cone angle 0 °). Defined as the value measured at a temperature of 25 ° C. at a shear rate of 0.0 s ⁻¹ .
In the present specification, “solid at room temperature” means a state that does not correspond to the above definition of “liquid at room temperature” and is not a gas.

Whether the liquid underfill material has started to react in the medium temperature region at room temperature 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)). The change can be confirmed by a change in peak (difference in reaction behavior) in differential scanning calorimetry (DSC) or the like. In the case of an underfill material that is solid at room temperature, it can be confirmed by a change 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 radical polymerizable compound. The radical polymerizable compound is not particularly limited, and a compound having an unsaturated double bond in the molecule is preferable. Examples of the radical polymerizable compound include a redox polymerizable compound, an emulsion emulsion polymerizable compound, and a (meth) acrylate compound. The radical polymerizable compound is preferably a (meth) acrylate compound in consideration of applicability to an electronic component device, controllability of a curing speed, handleability of an underfill material, and the like. As the radical 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 radical polymerizable compound, the content of other radical polymerizable compounds other than the (meth) acrylate compound in the total amount of all radical polymerizable compounds contained in the underfill material is 10%. It is preferably at most 5 mass%, more preferably at most 5 mass%, even more preferably at most 1 mass%, and it is preferred that substantially no other radically polymerizable compound is contained.

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

  Examples of the polyfunctional (meth) acrylate compound include diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, trimethylolpropane diacrylate, trimethylolpropane triacrylate, 1,4-butanediol diacrylate, , 6-hexanediol diacrylate, polyethylene glycol diacrylate, polypropylene glycol diacrylate, tricyclodecane dimethylol diacrylate, ditrimethylolpropane tetraacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, tris ( Triacryle of β-hydroxyethyl) isocyanurate G, polycarbonate acrylate, urethane acrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, trimethylolpropane dimethacrylate, trimethylolpropane trimethacrylate, 1,4-butanediol dimethacrylate, 1,6-hexane Diol dimethacrylate, polyethylene glycol dimethacrylate, polypropylene glycol dimethacrylate, tricyclodecane dimethylol dimethacrylate, ditrimethylolpropane tetramethacrylate, pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate, dipentaerythritol hexamethacrylate, tris (β-hydroxyethyl ) Trimethacrylate isocyanurate, polycarbonate methacrylates, urethane methacrylates, and difunctional (meth) acrylate compounds represented by the following structural formula (II). Among these, a liquid bifunctional (meth) acrylate compound represented by the following structural formula (II) is preferable because it is liquid at room temperature, and thus can impart good hot fluidity to the underfill material.

In the 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 numbers m and n, which are the numbers of structural units, indicate integer values for a single molecule, but indicate rational numbers that are average values as 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. Preferably, m and n are each independently a number from 1 to 15.

  Specific examples of the bifunctional (meth) acrylate compound represented by the structural formula (II) include, for example, a bifunctional (meth) acrylate compound represented by the following structural formula (III) and a bifunctional (meth) acrylate compound represented by the following structural formula (IV) A bifunctional (meth) acrylate compound is exemplified.

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

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

  Examples of the monofunctional (meth) acrylate compound include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, 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) acryle G, 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] dec-3-en-8-yloxyethyl (meth) acrylate, 2- (tricyclo) [5.2.1.02,6] dec-3-en-9-yloxyethyl (meth) A) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, dimer diol mono (meth) acrylate, diethylene glycol (meth) acrylate, polyethylene glycol (meth) acrylate, polypropylene glycol (meth) acrylate, 2 -Methoxyethyl (meth) acryl , 2-ethoxyethyl (meth) acrylate, 2-butoxyethyl (meth) acrylate, methoxydiethylene glycol (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, 2-phenoxyethyl (meth) acrylate, phenoxydiethylene glycol (meth) Acrylate, phenoxy polyethylene 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 Siethyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, 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) ) Acryloxyethyl phenyl acid phosphate, β- (meth) acryloyloxyethyl hydrogen phthalate, β- (meth) acryloyloxyethyl hydrogen succinate and ethylene oxide-modified neopentyl glycol (meth) acrylate, 2- (meth) a Liloyloxyethyl succinic acid, 2-methacryloyloxyethyl hexahydrophthalic acid, isobonyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, Dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, 2- (meth) acryloyloxyethylphthalic acid, 2- (meth) acryloyloxyethyl-2-hydroxyethylphthalic acid, and neopentyl glycol (meth) acryl Acid benzoates.

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

  From the viewpoint of stress relaxation and adhesive strength of the underfill material, the underfill material preferably contains at least one radical polymerizable compound 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 that at least one of these is contained. From the viewpoint of the difficulty in curing in the medium temperature range and the adhesive force, it is more preferable to include at least one radical polymerizable compound having a functional group equivalent of 300 to 700.

  In general, as the numerical value of the functional group equivalent increases, the crosslinked structure formed by the curing reaction tends to be less dense and 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 numerical value of the functional group equivalent increases. The same applies to the case where the number of functional groups in one molecule is small. The number of functional groups in one molecule of the radically polymerizable compound is preferably 1 to 3, and more preferably 2 or 3, from the viewpoint of achieving both stress relaxation and excellent adhesiveness. As a result, an underfill material having excellent stress relaxation and excellent adhesiveness can be obtained.

  Here, the functional group equivalent is defined as a value obtained by dividing the theoretical molecular weight by the number of functional groups or a value obtained by dividing the weight average molecular weight of one molecule measured by gel permeation chromatography (GPC) by the number of unsaturated double bonds. Define. If the molecule falls within the range, the skeleton is not specified. The radical polymerizable compound having a functional group equivalent within the above range is, for example, a compound having a functional group at a terminal and having a long main chain in a molecule, a long side chain or a branch in a molecule. Compounds having a divided bulky side chain are exemplified. When a radical polymerizable compound having a functional group equivalent within the above numerical range is used, a crosslinked structure formed by a curing reaction by light or heat tends to be sparse. When a compound having a functional group at the terminal and having a long main chain in the molecule is used, the functional group is at the terminal, so the distance between reaction points becomes longer, thereby tending to reduce stress. There is a tendency. Also, the presence of long side chains and bulky side chains creates a space around them, and tends to produce dense and sparse portions. This tends to alleviate the stress. For this reason, an 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 adhesive strength.

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

Equipment: (pump: L-2130 type [manufactured by Hitachi High-Technologies Corporation])
(Detector: RI type L-2490 [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 (three in total) (trade name, manufactured by Hitachi Chemical Co., Ltd.)
Column size: 10.7mm (inner diameter) x 300mm
Eluent: Tetrahydrofuran Sample concentration: 10mg / 2mL
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 a (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 and the (meth) acrylate compound A2 having a functional group equivalent of less than 250 is 5: 3 to 1:10. Preferably, it is 5: 4 to 1: 9, 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 the following organic peroxides: azobisisobutyronitrile, azobis-4-methoxy-2,4-dimethylvaleronitrile, azobiscyclohexanone-1-carbonitrile, azodibenzoyl, and the like. And redox catalysts obtained by combining a water-soluble catalyst such as potassium persulfate and ammonium persulfate with a peroxide or 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, it is preferable to contain at least one organic peroxide from the viewpoint of storage stability.

  Examples of the organic peroxide include ketone peroxides such as methyl ethyl ketone peroxide and cyclohexanone peroxide; 1,1-di (t-butylperoxy) cyclohexane, 2,2-di (4,4-di (t- Peroxyketals such as butylperoxy) cyclohexyl) propane; p-menthane hydroperoxide, diisopropylbenzene hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, cumene hydroperoxide, t-butylhydro Hydroperoxides such as peroxides; di (2-t-butylperoxyisopropyl) benzene, dicumyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, t-butylcum Luper oxide, di dialkyl peroxides such as t-hexyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne-3 and di-t-butyl peroxide; dibenzoyl peroxide, di (4 Diacyl peroxides such as -methylbenzoyl) peroxide; peroxydicarbonates such as di-n-propylperoxydicarbonate and diisopropylperoxydicarbonate; and 2,5-dimethyl-2,5-di (benzoylperoxy) ) Peroxyesters such as hexane, t-hexylperoxybenzoate, t-butylperoxybenzoate and t-butylperoxy-2-ethylhexanonate.

  Among these, a dialkyl peroxide having a phenyl group in the organic peroxide is preferable from the viewpoint of temperature stability particularly 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 radical polymerizable compound, and from the viewpoint of curability, is preferably 0.5 part by mass to 10 parts by mass. More preferably, the amount is part by mass. When the content of the radical polymerization initiator is 20 parts by mass or less based on 100 parts by mass of all the radical polymerizable compounds, volatile components are hardly generated, and the generation of voids in the cured product tends to be suppressed. When the content of the radical polymerization initiator is 0.3 parts by mass or more based on 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 from 90C to 150C, and more preferably from 100C to 140C 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 with the supplied underfill material is left in a medium temperature region (for example, on a stage of a hot plate). The start of the reaction tends to be suppressed. If the 10-hour half-life temperature of the radical polymerization initiator is 150 ° C. or less, the curing rate of the underfill material in a high-temperature region (a temperature at which the electronic component and the wiring board are joined via a joining portion) tends to be increased. is there. As a result, generation of voids tends to be suppressed.

  The half-life temperature of the radical polymerization initiator is a value (° C.) calculated by the following equation. The half-life temperature is described in a commercial product 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 the half concentration τ (time factor) becomes 50% can be determined by calculation. The concentration is measured using an iodine titration method.

(C) The specific silane compound The specific silane compound has a chain functional 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. Having a structure. The chain hydrocarbon group having 4 to 9 carbon atoms preferably has 5 to 9 carbon atoms, and more preferably 6 to 8 carbon atoms. 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 include a vinyl group, a glycidyl group, an acryloyl group, a methacryloyl group, a styryl group, an amino group, a ureide group, a mercapto group, a sulfide group and an 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 preferred.

In the specific silane compound, the chain hydrocarbon group having 4 to 9 carbon atoms may be branched and may contain an unsaturated bond. The number of the reactive functional groups may be one or more, and the functional groups may have a substituent in addition to the reactive functional groups. In addition, when the 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 branch or the substituent. Shall not be included.
In the chain hydrocarbon group having 4 to 9 carbon atoms, it is preferable that one reactive functional group is 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 each independently a hydrogen atom, a methyl group, a methoxy group, an ethyl group, an ethoxy group, a phenyl group or a phenoxy group, and R ₄ is each a vinyl group. Glycidyl 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, and n is 4-9. n is preferably from 5 to 9, and more preferably from 6 to 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,} More preferably, it is an ethoxy group or a phenoxy group, and even more preferably, 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 one may be used. Examples of commercially available specific silane compounds include, for example, KBM-1063 (5-hexenyltrimethoxysilane) and KBM-1083 (7-octenyltrimethoxysilane), which are silane coupling agents manufactured by Shin-Etsu Chemical Co., Ltd. KBM-4803 (8-glycidoxyoctyltrimethoxysilane) and KBM-5803 (8-methacryloyloxyoctyltrimethoxysilane).

  The content of the specific silane compound is preferably from 0.15% by mass to 3.0% by mass, more preferably from 0.25% by mass to 2.0% by mass, based on 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 a medium temperature region obtained by containing 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.

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

(Inorganic filler)
The underfill material may contain an inorganic filler. The type of the inorganic filler is not particularly limited. For example, spherical silica, silica such as crystalline silica, calcium carbonate, clay, alumina, silicon nitride, silicon carbide, boron nitride, calcium silicate, potassium titanate, aluminum nitride, beryllia, zirconia, zircon, fosterite, steatite, spinel , Mullite, 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, spherical beads, glass fibers, and the like. From the viewpoint of fluidity and permeability of the underfill material into the fine gap, spherical silica is preferred. One type of inorganic filler may be used alone, or two or more types may be used in combination. When two or more inorganic fillers are used in combination, for example, when two or more inorganic fillers having the same component but different average particle diameters are used, two or more inorganic fillers having the same average particle diameter and different components are used. And two or more kinds of inorganic fillers having different average particle diameters and kinds are used.

  The inorganic filler is preferably treated with a coupling agent from the viewpoint of the effect of suppressing the reaction in a medium temperature range. Examples of the coupling agent include various silane compounds such as epoxy silane, mercapto silane, amino silane, alkyl silane, ureido silane, and vinyl silane, a titanium compound, an aluminum chelate compound, and an aluminum zirconium compound. 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) Agents are 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 preferably has 20 or less carbon atoms, 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. A combination of a hydrogen group and an alicyclic hydrocarbon group having a total carbon number of 30 or less is exemplified. The alkylene group represented by R ₅ may be branched, may contain a double bond, and 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 in the alkyl group includes the number of carbon atoms contained in the branch.

  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, an aryloxy group having 1 to 15 carbon atoms, Examples 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 carbon number of the alkylene group does not include the carbon number of 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). R ₆ each 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 More preferably, it is 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. A combination of a hydrogen group and an alicyclic hydrocarbon group having a total carbon number of 30 or less is exemplified. The alkyl group having 1 to 30 carbon atoms may be branched, may contain a double bond, and 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 in the alkyl group includes the number of carbon atoms contained in the branch.

  In the case of using an inorganic filler surface-treated with a coupling agent, the inorganic filler previously surface-treated may be mixed with other components (a pre-treatment method), and the inorganic filler that has not been surface-treated may be mixed with the inorganic filler. The surface treatment may be performed by mixing the agent with other components (separate addition method). From the viewpoint of suppressing the start 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 inorganic filler is subjected to surface treatment with a coupling agent, the amount of the coupling agent is preferably 0.05% by mass to 5% by mass, and more preferably 0.1% by mass to 5% by mass with respect to 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 with respect to the inorganic filler, the adhesiveness to the component of the electronic component tends to be improved, and when the amount is 5% by mass or less, the molding is performed. Properties, void properties, and heat resistance in a medium temperature range tend to be improved.

  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 still more preferably 1 μm or less. The average particle diameter of the inorganic filler is preferably 0.1 μm or more. When the average particle diameter of the inorganic filler is 5 μm or less, the permeability and fluidity of the underfill material into the fine gaps are improved, so that voids and unfilling are less likely to occur, and the connection between the semiconductor element and the wiring board is reduced. Inorganic fillers are less likely to bite into the parts, and connection failures tend to be less likely to occur.

  In the present specification, the average particle diameter of the inorganic filler is defined as the particle diameter at which the cumulative distribution is 50% in the cumulative distribution represented by the cumulative particle frequency, in which the particle diameter is graded and the volume is frequency using the following method. Means As a method of measuring the particle diameter of particles, for example, a method of collectively measuring a large number of particles using an apparatus such as laser diffraction, dynamic light scattering, small-angle X-ray scattering, an electron microscope, an atomic force microscope And the like, and measuring the particle diameter of each particle. Before the measurement of the particles, a pretreatment for separating particles of 100 μm or more may be performed by using a method such as liquid phase centrifugal sedimentation, field flow fractionation, particle size exclusion chromatography, and fluid dynamics 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 more 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, the thickness is preferably 20 μm or less, more preferably 15 μm or less, and even more preferably 10 μm or less. When the maximum particle diameter of the inorganic filler is 20 μm or less, the permeability and fluidity of the underfill material into the fine gap are improved, so that voids and unfilling are less likely to occur, and the connection between the electronic component and the wiring board is reduced. Inorganic fillers are less likely to bite into the parts, and connection failures tend to be less likely to occur.

  As a method of measuring the maximum particle diameter of the inorganic filler, for example, a method of collectively measuring a large number of particles using a device such as laser diffraction, dynamic light scattering, small-angle X-ray scattering, and electron microscope, atomic A method of imaging using an atomic force microscope or the like and measuring the particle diameter of each particle is exemplified.

  The content of the inorganic filler in the underfill material is not particularly limited. For example, the content is preferably 20% by mass or more, more preferably 30% by mass or more, even more preferably 40% by mass or more based on the total mass of the underfill material. Further, the content of the inorganic filler is preferably 70% by mass or less based on 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.

  In the underfill material, other fillers than the inorganic filler may be used. The content of the other filler in the entire 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 no inorganic filler is 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 is not particularly limited. For example, it is preferably 0.05% by mass to 1% by mass, more preferably 0.08% by mass to 0.7% by mass, and more preferably 0.1% by mass to 0.1% by mass in the total amount of the underfill material. More preferably, it is 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 hardly inhibited. It is in.

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

  Commercially available rubber products include, for example, "Paraklon RP" series manufactured by Negami Kogyo Co., Ltd., "Staphyloid IM" series and "Staphyloid AC" series manufactured by Ganz Kasei Co., Ltd. Series, "METABLEN 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 Arkema Co., Ltd. Can be

  Commercial products of low molecular weight rubber crosslinking agents include, for example, "Ricon" series manufactured by SARTOMER Co., Ltd., "poly bd" series, "poly ip" series, "epol" series and "KRASOL" manufactured by Idemitsu Co., Ltd. And "NISSO-PB" manufactured by Nippon Soda Co., Ltd. These may be used alone or in combination of two or more.

  When the underfill material contains a flexible agent, the content 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, based on the total amount of the underfill material. preferable. When the content of the flexible agent is 1% by mass or more, the stress tends to be excellent, and when the content is 30% by mass or less, the dispensing property tends to be excellent.

(Thixotropic agent)
When the underfill material is liquid at room temperature, it may contain a thixotropic agent. By including a thixotropic agent in a liquid underfill material at room temperature, the generation of voids tends to be suppressed. In other words, if the underfill material is supplied on the substrate and flows without being able to maintain the shape, the voids are likely to be involved, but the inclusion of the thixotropic agent makes the underfill material less likely to flow. And voids are less likely to occur.

  The type of the thixotropic agent is not particularly limited, and a thixotropic agent generally used in an organic resin composition for an electronic component can be used. Specifically, for example, hydrogenated castor oil compounds obtained by adding hydrogen to castor oil, polyethylene oxide compounds obtained by oxidizing polyethylene to introduce polar groups, amide wax synthesized from vegetable oil fatty acids and amines Compounds, salts of long chain polyaminoamides and acid polymers, unsaturated polycarboxylic acid polymers, finely divided silica, and crushed silica.

  Among the thixotropic agents, salts of long-chain polyaminoamide and acid polymer, unsaturated polycarboxylic acid polymer, finely divided silica, and crushed silica are preferred from the viewpoint of handling properties, moldability, and reduction of voids. .

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

  The fine powder silica as the thixotropic agent preferably has an average primary particle diameter of 5 nm to 200 nm, more preferably 5 nm to 50 nm. Further, a material whose surface is treated with silicone oil or a coupling agent may be used. Examples of the fine powder silica include R974 (Nippon Aerosil Co., Ltd., trade name) having an average primary particle diameter of 12 nm and surface-treated with dimethylsilane, and RX200 (Japan, having an average primary particle diameter of 12 nm and surface-treated with trimethylsilane). Aerosil Co., Ltd.), RY200 (Nippon Aerosil Co., Ltd.) having an average primary particle diameter of 12 nm and surface-treated with dimethylsiloxane, R202 (Japan Aerosil Co., Ltd.) having an average primary particle size of 14 nm and surface-treated with dimethylsiloxane Aerosil Co., Ltd.), RA200H having an average primary particle diameter of 12 nm and surface treated with aminosilane (Nippon Aerosil Co., Ltd.), R805 having an average primary particle size of 12 nm and surface treatment with alkylsilane (Nippon Aerosil Co., Ltd.) Co., Ltd., trade name), average primary particle size is 12 m7, R7200 (Nippon Aerosil Co., Ltd., trade name) surface-treated with methacryloxysilane and YA050C-SP3 (Admatex Co., Ltd., trade name) having an average primary particle diameter of 50 nm and surface-treated with phenylsilane Available as a product.

  The crushed silica as the thixotropic agent preferably has an average particle size of 10 nm or less, more preferably 7.5 nm or less, and even more preferably 5.5 nm or less. Further, from the viewpoint of dispersibility in the resin and agglomeration of the crushed silica itself, the crushed silica preferably has an average particle size of 4.5 nm or more. A crushed silica whose surface is treated with a 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 commercial 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 electronic components can be used. As the polymer component, for example, 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, urethane resin And acrylic rubber. Among these, phenoxy resins, polyimide resins, acrylic rubbers, cyanate ester resins, and polycarbodiimide resins are preferable, and phenoxy resins, polyimide resins, and acrylic rubbers are more preferable from the viewpoint of excellent heat resistance and film formability. These polymer components can be used alone or as a mixture or copolymer of two or more. 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 a tetracarboxylic dianhydride and a 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. To perform the addition reaction. In order to suppress the deterioration of the properties of the underfill material, the tetracarboxylic dianhydride is preferably subjected to recrystallization purification treatment with acetic anhydride.

  The glass transition temperature (Tg) of the polymer component is preferably 100 ° C. or lower, more preferably 85 ° C. or lower, from the viewpoint of excellent adhesion of the underfill material. If the Tg is 100 ° C. or lower, bumps formed on electronic components, electrodes formed on a wiring board, wiring patterns, and other irregularities can be easily buried with an underfill material, and bubbles are less likely to remain and voids are generated. Tends to be difficult. The above Tg was measured using a differential scanning calorimeter (DSC) (for example, Perkin Elmer, DSC-7 type) under the conditions of a sample amount of 10 mg, a heating rate of 10 ° C./min, and an atmosphere of measurement: air. Is the value of

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

  Although the content of the polymer component is not particularly limited, from the viewpoint of maintaining the shape (film shape or the like) of the underfill material well, when the polymer component is contained with respect to 100 parts by mass of the radical polymerizable compound, It is preferably from 5 parts by mass to 500 parts by mass, more preferably from 5 parts by mass to 300 parts by mass, even more preferably from 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 forming property 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 force is improved. Tends to improve.

(Flux agent)
The underfill material may contain a fluxing agent. The type of the flux agent is not particularly limited, and a conventionally used amine salt of hydrohalic acid or 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, abietic acid, adipic acid, ascorbic acid, citric acid, -Preferred acids include organic acids such as furan carboxylic acid and malic acid, compounds containing two or more alcoholic hydroxyl groups in one molecule, organic acid salts such as metal sulfonates and metal carbonyl salts, and quinolinol derivatives. Can be More preferably, an organic acid or an organic acid salt is used. One flux agent may be used alone, or two or more flux agents may be used in combination.

  When the underfill material contains a fluxing agent, its content is not particularly limited. For example, the amount 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 be generated, and reliability such as migration resistance tends to be improved.

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

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

  Other ion trapping agents include, for example, hydrated oxides of elements selected from magnesium, aluminum, titanium, zirconium and antimony. One type of ion trapping agent may be used alone, or two or more types may be used in combination.

  When the underfill material contains an ion trapping agent, its content is preferably 0.1% by mass to 5.0% by mass based on the total amount of the radical polymerizable compound contained in the underfilling agent. More preferably, the content is 1.0% by mass to 3.0% by mass. The average particle size of the ion trapping 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 trapping agent are measured using the same method as that for 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 fillet properties. The type of the surfactant is not particularly limited, and a surfactant generally used in an organic resin composition for an electronic component can be used. Examples of the surfactant include a nonionic surfactant. Examples of the nonionic surfactant include polyoxyalkylene alkyl ether surfactants such as polyoxyethylene alkyl ether, sorbitan fatty acid ester surfactant, polyoxyethylene sorbitan fatty acid ester surfactant, and polyoxyethylene sorbitol fatty acid. Ester surfactant, glycerin fatty acid ester surfactant, polyoxyethylene fatty acid ester surfactant, polyoxyethylene alkylamine surfactant, alkyl alkanolamide surfactant, polyether-modified silicone surfactant, aralkyl-modified silicone surfactant 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 preferred.

  As the surfactant, for example, BYK-307, BYK-333, BYK-377, and BYK-323 (Bik Chemie Japan, trade name) are commercially available.

  In addition to the above surfactants, a silicone-modified epoxy resin can be used as the surfactant. The silicone-modified epoxy resin can be obtained as a reaction product between an organosiloxane having a functional group that reacts with an epoxy group and the 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, etc. in one molecule. No. These organosiloxanes include, for example, BY16-799, BY16-871 and BY16-004 (Dow Corning Toray, trade name), and X-22-1821 and KF-8010 (Shin-Etsu Chemical Co., Ltd., trade name) ) Is commercially available.

  The weight average molecular weight of the organosiloxane measured by GPC (gel permeation chromatography) is preferably in the range of 500 to 5,000, more preferably in the range of 1,000 to 3,000. When the weight average molecular weight is 500 or more, the compatibility with the resin is prevented from being excessively improved, and the effect as an additive tends to be more easily exhibited. When the weight average molecular weight is 5,000 or less, a decrease in compatibility with the resin is suppressed, separation and bleeding from the cured product of the silicone-modified epoxy resin are less likely to occur, and the adhesiveness and appearance tend to be hardly 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. Use an epoxy resin generally used in an organic resin composition for electronic components. Can be. Specifically, for example, glycidyl ether type epoxy resin obtained by the reaction of bisphenol A, bisphenol F, bisphenol AD, bisphenol S, naphthalene diol, hydrogenated bisphenol A, etc. with epichlorohydrin; orthocresol novolak type epoxy resin; A novolak epoxy resin obtained by epoxidizing a novolak resin obtained by condensation or cocondensation of a phenol compound and an aldehyde compound; a glycidyl ester epoxy resin obtained by reacting a polybasic acid such as phthalic acid or dimer acid with epichlorohydrin; Glycidylamine type epoxy resin obtained by reaction of polyamine such as diaminodiphenylmethane, isocyanuric acid and epichlorohydrin; and oxidized olefin bond with peracid such as peracetic acid. That include linear aliphatic epoxy resin and alicyclic epoxy resin. These may be used alone or in combination of two or more. The epoxy resin used to obtain the silicone-modified epoxy resin is preferably a 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. As such a silane compound, for example, a silane compound commercially available as a silane coupling agent that does not correspond to a specific silane compound may be mentioned.

  Examples of the silane coupling agent include aminosilane coupling agents, epoxy silane coupling agents, ureido silane coupling agents, isocyanate silane coupling agents, vinyl silane coupling agents, acrylic silane coupling agents, methacryl silane coupling agents, and ketimines. Examples of the silane coupling agent include an isocyanate silane coupling agent, an acrylic silane coupling agent, a methacrylsilane silane coupling agent, and an epoxy silane coupling agent. 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, its content is not particularly limited. For example, the total content of the specific silane coupling agent and the 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 preferred. When the content is 10% by mass or less, the silane coupling agent hardly vaporizes due to heat at the time of mounting, and a void tends to be hardly generated.

(Other components)
As the underfill material, a dye, a coloring agent such as carbon black, a diluent, or the like can be used as necessary as other additives.

(Physical properties)
The thixotropic index of the underfill material is preferably 1.0 or more, more preferably 1.5 or more, and even more preferably 2.0 or more.

The stiffness index of the underfill material is (viscosity at a shear rate of 0.5 s ⁻¹ ) / (5.0 s ⁻ ) when the viscosity of the underfill material kept at 25 ° C. is measured using a rheometer. Viscosity at a shear rate of ¹ ). The viscosity at a shear rate of 0.5 s ^-1 and the viscosity at a shear rate of 5.0 s ^-1 were measured using a rotary shear viscometer equipped with a cone plate (diameter 40 mm, cone angle 0 °). Let the value be 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. S to 110 Pa · s is more preferable.
The viscosity in the middle temperature range 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. 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.

<Production method of underfill material>
(Method of producing liquid underfill material at room temperature)
The method for producing the underfill material that is liquid at room temperature is not particularly limited. For example, a liquid underfill material can be manufactured at room temperature by weighing a predetermined component, mixing and kneading using a mill, a mixing roll, a planetary mixer, etc., and defoaming as necessary. .

(Method of manufacturing a solid underfill material at room temperature)
The method for producing the underfill material that is solid at room temperature is not particularly limited. For example, if the solid underfill material at room temperature is in the form of a film, first weigh a predetermined component, dissolve or disperse by stirring, mixing, kneading, etc. to prepare a resin varnish, and release the resin varnish. It can be produced by applying a knife coater, a roll coater, an applicator or the like on the substrate film subjected to the above, and removing the organic solvent by heating.

  The organic solvent used for the preparation of the resin varnish preferably has a property capable of uniformly dissolving or dispersing each component. For example, 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. Can be These organic solvents can be used alone or in combination of two or more. The stirring and mixing or kneading at the time of preparing the resin varnish can be performed using, for example, a stirrer, a raker, a three-roll, ball mill, a bead mill, or a homodisper.

  The substrate film is not particularly limited as long as it has heat resistance that can withstand the heating conditions when evaporating 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, the respective layers may be made of different materials, or may be made of the same material.

  The drying conditions when the organic solvent is volatilized from the resin varnish applied on the base film are preferably set to conditions under which the organic solvent is sufficiently volatilized. Specifically, for example, the reaction can be performed at 50 ° C. to 200 ° C. for 0.1 minute to 90 minutes.

<Electronic component device>
The electronic component device of the present embodiment includes a cured product of the above-described pre-supply type underfill material.
In one embodiment, an electronic component device includes: an electronic component; and a wiring board arranged to face the electronic component and electrically connected to the electronic component via a bonding portion. A cured product of a mold underfill material has a structure arranged between the electronic component and the wiring board.

  As the electronic component device, for example, a lead frame, a wired tape carrier, a rigid and flexible wiring board, glass, a support member (wiring substrate) such as a silicon wafer, an active element such as a semiconductor chip, a transistor, a diode, and a thyristor; An electronic component device obtained by mounting an electronic component such as a passive element such as a capacitor, a resistor, a resistor array, a coil, and a switch, and sealing a necessary portion with an underfill material is exemplified.

  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 to a wiring formed on a rigid or flexible wiring board or a glass plate by bump connection. Specifically, for example, flip-chip BGA (Ball Grid Array), LGA (Land Grid Array) and COF (Chip On Film) electronic component devices can be mentioned.

  In the field of the flip chip in which the underfill material of the present embodiment is particularly suitable, a lead-free solder such as a Sn-Ag-Cu-based bump material is used for a bump material of a connection portion connecting a wiring board and a semiconductor element of an electronic component. A flip chip semiconductor device is exemplified. By using the underfill material of the present embodiment, good reliability can be maintained even for a flip chip that is bump-connected with lead-free solder that is physically brittle compared to conventional lead solder.

<Manufacturing method of electronic component device>
The method for manufacturing an electronic component device according to the present embodiment is a method for manufacturing an electronic component device for manufacturing an electronic component device by electrically bonding an electronic component and a wiring board via a bonding portion,
A supply step of supplying the above-described pre-supply type underfill material to at least one surface of the surface of the electronic component facing the wiring substrate or at least one surface of the wiring substrate facing the electronic component,
A joining step of joining the electronic component and the wiring board via a joining portion and curing the pre-supply type 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 underfill material in the form of a film is supplied by sticking. In the bonding step, the bonding between the electronic component and the wiring board may be performed together with the curing of the underfill material.

In one embodiment, a method for manufacturing an electronic component device includes the following steps.
(1) a supply step of supplying an underfill material to at least one of a surface of the electronic component facing the wiring substrate or a surface of the wiring substrate facing the electronic component; and (2) a step of supplying the electronic component and the wiring substrate. Are pressed and opposed via the metal bumps of the connection portion, thereby filling a gap between the electronic component and the wiring board with an underfill material, and connecting the electronic component and the wiring board to each other. Pressurizing step of contacting via the metal bump of the portion (3) applying the electronic component and the wiring board via the metal bump of the connecting portion during at least one of the pressing process and after the pressing process; A bonding step (heat treatment step) of bonding the electronic component and the wiring board via the metal bumps of the connection portion by performing a heat treatment while pressing and contacting the electronic component and the wiring board.

Hereinafter, a method for 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 to this. Further, the size of the members in each drawing is conceptual, and the relative relationship between the sizes of the members is not limited to this.
FIG. 1 is a sectional view schematically showing steps 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 shown in FIG. 1, a mode in which a pre-supply type underfill material is adhered 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 embodiments.

  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, an underfill material 6 is applied to the surface of the wiring board 5 on the side where the connection pads 3 are provided (the side of the wiring board 5 facing the semiconductor chip 1) (supply step). Examples of a method for 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 where the connection pads 3 are provided, or may be applied to a part of the area of the wiring board 5 where the connection pads 3 are provided. By applying the underfill material 6 to a part of the region of the wiring board 5 where the connection pads 3 are provided, the underfill material 6 is used 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 substrate 5 and the semiconductor chip 1. As a pattern for applying the underfill material 6 to the wiring board 5, a cross shape or a double cross shape along a diagonal line of a region where the semiconductor chip 1 of the wiring substrate 5 is arranged is preferable.

  Then, in FIG. 1B, the semiconductor chip 1 and the wiring board 5 are opposed to each other while being pressed via the solder bumps 2, so that the gap between the semiconductor chip 1 and the wiring board 5 is filled with the underfill material 6. The semiconductor chip 1 is filled and the connection pads 3 of the wiring board 5 are brought into contact with each other via the solder bumps 2 (pressing step).

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

  Further, as a pressing condition when the semiconductor chip 1 and the connection pads 3 of the wiring board 5 are brought into contact with each other via the solder bumps 2, it is preferable that the weight per bump is 0.002N to 200N, It is more preferably 0.01N to 100N, and further preferably 0.02N to 20N. Under this pressurizing condition, the bonding between the semiconductor chip 1 and the connection pads 3 of the wiring substrate 5 via the solder bumps 2 in the heat treatment step described later may be performed.

  During the pressurizing step and / or at least after the pressurizing step, the semiconductor chip 1 and the connection pads 3 of the wiring substrate 5 are subjected to heat treatment in a state where they are pressed and contacted via the solder bumps 2 and the semiconductor chip 1 The connection pads 3 of the wiring board 5 are joined via the solder bumps 2 and the underfill material 6 is cured (heat treatment step).

  The temperature of the heat treatment is preferably from 150C to 350C, more preferably from 220C to 300C, even more preferably from 240C to 270C. 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 at a temperature in the range of 120 ° C to 200 ° C for 0.5 to 6 hours.

  Through the above steps, the electronic component device of the present embodiment is manufactured.

  FIG. 2 is a sectional view schematically showing steps 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 to be formed is formed on the substrate 20 having the wiring 15. Further, the connection bumps 30 are formed in the openings of the solder resist 60. Although it is not necessary to provide the solder resist 60, by providing the solder resist on the substrate 20, the occurrence of bridges between the wirings 15 can be suppressed, and the connection reliability and the insulation reliability can be improved. The solder resist 60 can be formed using, for example, a commercially available solder resist ink for a package. Specific examples of commercially available solder resist inks for packages include SR series (trade name, manufactured by Hitachi Chemical Co., Ltd.) and PSR4000-AUS series (trade name, manufactured by Taiyo Ink Mfg. Co., Ltd.).

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

  After attaching the film-like underfill material 40 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 using a connection device such as a flip chip bonder. Subsequently, the semiconductor chip 10 and the substrate 20 are pressure-bonded while being heated at a temperature equal to or higher than the melting point of the connection bump 30, and the semiconductor chip 10 and the substrate 20 are connected via the connection bump 30 as shown in FIG. Connecting. At this time, the gap between the semiconductor chip 10 and the substrate 20 is filled with the film-like underfill material 40. Thus, the electronic component device 600 is obtained.

  In the method of manufacturing an electronic component device according to the present embodiment, the semiconductor device is temporarily fixed after alignment (in a state where an electronic component adhesive is interposed), and is heated in a reflow furnace to melt the connection bumps 30 and to form the semiconductor. The chip 10 and the substrate 20 may be connected. At the stage of temporary fixing, since it is not always necessary to form a metal bond, the crimping can be performed with a lower load, in a shorter time, and at a lower temperature than in the above-described method of crimping while heating. For this reason, the productivity tends to be improved and the deterioration of the connection portion tends to be suppressed.

  After connecting the semiconductor chip 10 and the substrate 20, a 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 curing of the underfill material proceeds, 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 preferable conditions are the same as those of the liquid underfill material at room temperature.

  Next, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.

(Preparation of underfill material)
The following components were blended in the amounts (units: parts by mass) shown in Tables 1 and 2, respectively, kneaded and dispersed with a three-roll mill and a mill, and then degassed in vacuum to obtain underscores of Examples and Comparative Examples. A fill material was produced. "-" In the table means that the corresponding component is not contained. All the prepared underfill materials were liquid at 25 ° C. Among the silane compounds 1 to 7, the silane compounds 1 to 4 correspond to the specific silane compound, and the silane compounds 5 to 7 do not correspond to the specific silane compound.

Radical polymerizable compound 1: A-DCP (manufactured by Shin-Nakamura Chemical Co., Ltd., tricyclodecane dimethanol diacrylate, functional group equivalent: 152 g / eq)
-Radical polymerizable compound 2: ABE-300 (manufactured by Shin-Nakamura Chemical Co., Ltd., ethoxylated bisphenol A diacrylate, functional group equivalent: 233 g / eq)
-Radical polymerizable compound 3: UA-13 (manufactured by Shin-Nakamura Chemical 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 (8-glycidoxyoctyltrimethoxysilane, manufactured by Shin-Etsu Chemical Co., Ltd.)
-Silane compound 4: KBM-5803 (8-methacryloyloxyoctyltrimethoxysilane, manufactured by Shin-Etsu Chemical Co., Ltd.)
-Silane compound 5: KBM-503 (3-methacryloyloxypropyltrimethoxysilane, manufactured by Shin-Etsu Chemical Co., Ltd.)
-Silane compound 6: KBM-403 (3-glycidoxypropyltrimethoxysilane, manufactured by Shin-Etsu Chemical Co., Ltd.)
-Silane compound 7: KBM-1003 (vinyltrimethoxysilane, manufactured by Shin-Etsu Chemical Co., Ltd.)
-Radical polymerization initiator: Perkadox BC-FF (Dicumyl peroxide, manufactured by Kayaku Akzo Co., Ltd.)
-Flexible agent: Nano Strength D51N (manufactured by Arkema, modified polymethyl methacrylate-polybutyl acrylate block copolymer, weight average molecular weight: 57000)
Polymerization inhibitor: SUMIRIZER GM (manufactured by Sumitomo Chemical Co., Ltd., 2-t-butyl-6- (3-butyl-2-hydroxy-5-methylbenzyl) -4-methylphenyl acrylate)
・ Flux agent: adipic acid (manufactured by Asahi Kasei Chemicals Corporation)
Thixotropic agent: R805 (Nippon Aerosil Co., Ltd., powdered silica having a volume average particle diameter of 12 nm)
Inorganic filler: SE-2050-SMJ (manufactured by Admatechs Co., Ltd., methacrylate silane coupling treatment with a volume average particle diameter of 0.5 μm and a maximum particle diameter of 5 μm (using a silane coupling agent having a 3-methacryloxypropyl group) Treated) spherical silica)

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

  Using a dispenser (needle diameter: 0.3 mm), an underfill material was applied in a cross shape to the chip mounting portion of the wiring board, and another cross shape was applied so as to be shifted by 45 ° and overlapped (total application amount: About 3 mg). Next, the wiring board to which the underfill material was applied was placed on the stage of a hot plate heated to 70 ° C., and left for 5 minutes, 30 minutes, 60 minutes or 90 minutes. Thereafter, the chip is mounted on the wiring board, and subjected to thermocompression bonding under the conditions of a load of 7.5 N, temperature / time: 260 ° C./5 seconds, and then cured at 175 ° C. for 1 hour to form a semiconductor device. I got

The wiring board used for manufacturing the electronic component device was 14 mm in length, 14 mm in width, and 0.30 mm in thickness, the core layer was E-679FG (Hitachi Chemical Co., Ltd., trade name), and the solder resist was AUS-. 308 (Taiyo Holdings Corporation, 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 for manufacturing the electronic component device is 7.3 mm long, 7.3 mm wide and 0.15 mm thick, and has bumps made 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 produced electronic component device was observed using an ultrasonic flaw detector (AT-5500, Hitachi Construction Machinery Co., Ltd., trade name), and the void occupancy was evaluated according to the following criteria.
A: Void area is 1% or less of total area B: Void area is more than 1% and 5% or less of total area C: Void area is more than 5% of total area and 20% or less D: Void area is 20% or less of total area More than%

  As is clear from the evaluation results, the electronic component device of the example manufactured using the underfill material containing the specific silane compound has a small void occupancy even when the standing time on the stage of the hot plate is increased. Was. Therefore, it can be seen that the underfill materials of the examples are excellent in voidlessness and stage stability.

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

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

1 semiconductor chips (electronic components)
2 solder bump 3 connection pad 4 solder resist 5 wiring board 6 underfill material 10 semiconductor chip (electronic component)
DESCRIPTION OF SYMBOLS 15 Wiring 20 Substrate 30 Connection bump 40 Film-like underfill material 60 Solder resist 600 Electronic component device

Claims (9)

A pre-supply type underfill material containing (A) a radical polymerizable compound, (B) a radical polymerization initiator, and (C) a silane compound represented by the following general formula (I) .


[In the general formula (I), R ₁ , R ₂ and R ₃ are each independently a methoxy group , R ₄ is a vinyl group, an acryloyl group, an acryloyloxy group, a methacryloyl group or a methacryloyloxy group , and n is 4 -9. ] In the general formula (I), R ₄ The pre-filled underfill material according to claim 1, wherein is a vinyl group. In the general formula (I), R ₄ The pre-filled underfill material according to claim 1, wherein is a methacryloyloxy group.   The pre-supply type underfill material according to any one of claims 1 to 3, further comprising an inorganic filler.   The pre-filled underfill material according to any one of claims 1 to 4, further comprising a flexible agent.   A cured product of the pre-supply type underfill material according to any one of claims 1 to 5.   An electronic component device comprising a cured product of the pre-supply type underfill material according to claim 6.   An electronic component, and a wiring board that is arranged to face the electronic component and is electrically connected to the electronic component via a bonding portion, and the cured product of the pre-supply underfill material is The electronic component device according to claim 7, wherein the electronic component device is disposed between the electronic component and the wiring board. An electronic component device manufacturing method for manufacturing an electronic component device by electrically bonding an electronic component and a wiring board via a bonding portion,
The surface of the electronic component on a side facing the wiring board or at least one surface of the wiring substrate on a side facing the electronic component according to any one of claims 1 to 5. A supply step of supplying a pre-supply type underfill material,
A bonding step of bonding the electronic component and the wiring board via a bonding portion and curing the pre-supply type underfill material.