JP2017114961A - Prior-supply type underfill material, method for producing electronic component device, and electronic component device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a prior-supply type underfill material that can shorten curing time, reduces voids, and has excellent adhesion to an electronic component.SOLUTION: A prior-supply type underfill material has (A) a compound having an ethylenic unsaturated double bond, (B) a reaction initiator, (C) an inorganic filler, and (D) a flexing agent. The (A) compound having an ethylenic unsaturated double bond has (A1) an adduct of epoxy resin and (meth) acrylic acid.SELECTED DRAWING: None

Description

  The present invention relates to a pre-supplied underfill material, an electronic component device manufacturing method, and an electronic component device.

  Conventionally, in the field of element sealing of electronic component devices such as transistors, ICs (Integrated Circuits), and LSIs (Large Scale Integrations), sealing is performed using a sealing material including a resin in terms of productivity and cost. The technique to do is becoming mainstream. As a sealing material, an epoxy resin composition is widely used. This is because the epoxy resin is balanced in various properties such as workability, moldability, electrical properties, moisture resistance, heat resistance, mechanical properties, and adhesion to inserts.

  In electronic component devices mounted with bare chips such as COB (Chip on Board), COG (Chip on Glass), and TCP (Tape Carrier Package), epoxy resin compositions that are liquid at room temperature are widely used as sealing materials. . Also, in an electronic component device (flip chip) in which electronic components are bump-connected on a wiring board having ceramic, glass epoxy resin, glass imide resin, polyimide film or the like as a substrate, the bump-connected electronic components and the wiring substrate An epoxy resin composition that is liquid at room temperature is also used as an underfill material that fills the gap. In bare chip mounting, the circuit formation surface is not sufficiently protected, so moisture and ionic impurities can easily enter.In flip chip mounting, the electronic components and the wiring board may have different coefficients of thermal expansion. Thermal stress may occur in the part. Therefore, the epoxy resin composition plays an important role in protecting electronic components from temperature and humidity and mechanical external force.

  As the filling method of the underfill material, after connecting the electronic component and the wiring board, a post-filling method in which the underfill material is infiltrated into the gap between the electronic component and the wiring board using a capillary phenomenon, and an underfill material is used. There is a pre-feeding method that connects the electronic component and the wiring board and cures the underfill material in a batch when the electronic component is first supplied onto the wiring board and thermocompression bonded to connect the electronic component to the wiring board. .

  In recent years, as electronic components have become highly integrated, multifunctional, and multi-pin, bumps have been reduced in diameter and pitch, and electronic components and wiring boards are connected using a reflow furnace. In some cases, the connection portion is destroyed by the stress generated during cooling. Therefore, there is an increasing demand for a pre-feed type underfill material (also referred to as a “pre-feed type underfill material”) that can connect an electronic component to the wiring board and protect the connection portion with the underfill material. ing.

If the underfill material used in the pre-feed method has low curability, the time for thermocompression bonding becomes longer, causing vacancies (hereinafter referred to as “voids”) due to volatile matter generated from electronic component devices, underfill materials, etc. Also referred to in the cured underfill material. Therefore, it is preferable that the underfill material used for the first supply method can be cured in a short time.
If voids are present in the cured product of the underfill material, the connection reliability is reduced due to thermal stress, and the moisture resistance reliability is reduced due to the penetration of moisture and ionic impurities. The generation is required to be suppressed.

  As a method for shortening the curing time of the epoxy resin composition, a method using an imidazole compound as a curing accelerator (see, for example, Patent Document 1), and a coating with a thermosetting resin around the imidazole compound as a curing accelerator. A method using at least one of fine sphere particles and amine adduct particles obtained in this manner (for example, see Patent Document 2) has been reported.

  In addition to the epoxy resin composition that can be cured for a short time, a reaction that can shorten the curing time includes a radical reaction. As an underfill material to which a radical reaction is applied, an underfill material using a resin composition containing a compound having a (meth) acryloyl group as a compound having an ethylenically unsaturated double bond capable of radical reaction is reported. (For example, see Patent Document 3).

Japanese Patent Publication No. 7-53794 Japanese Patent No. 3446730 JP 2009-164477 A

  However, even when an epoxy resin composition containing an imidazole compound as a curing accelerator is used as an underfill material of a pre-feed system, a relatively long time is required for curing by thermocompression bonding, so voids are likely to occur. . Therefore, an electronic component device obtained using such an epoxy resin composition as an underfill material has insufficient connection reliability.

  Furthermore, the underfill material using a compound having an ethylenically unsaturated double bond can be cured in a short time as compared with the epoxy resin composition, but has a large amount of shrinkage at the time of curing and expansion / contraction due to heat. The adhesiveness with a component is low, and the electronic component device obtained by using such an underfill material has insufficient connection reliability.

  For this reason, an underfill material that is applied to a pre-feed method, can reduce the curing time, has less voids, and is excellent in adhesiveness with an electronic component is required, but has not yet been obtained.

  The present invention has been made in view of such circumstances, a pre-feed type underfill material capable of shortening the curing time, generating less voids, and having excellent adhesion to an electronic component, and the pre-feed type Electronic component device manufacturing method capable of manufacturing an electronic component device excellent in electrical connection reliability using an underfill material, and an electronic component device excellent in electrical connection reliability and generating less voids It is an issue to provide.

Specific means for solving the above problems include the following embodiments.
<1> (A) a compound having an ethylenically unsaturated double bond, (B) a reaction initiator, (C) an inorganic filler, and (D) a flexible agent. A pre-feed type underfill material in which the compound having a double bond contains an addition reaction product of (A1) an epoxy resin and (meth) acrylic acid.

<2> The pre-supplied underfill material according to <1>, wherein the addition reaction product of the (A1) epoxy resin and (meth) acrylic acid is a compound represented by the following general formula (I-1).

(In the general formula (I-1), each of R ¹¹ independently represents a hydrogen atom or a methyl group, and each of R ¹² independently represents a C 1-18 divalent which may have a substituent. Represents a hydrocarbon group, R ¹³ represents an optionally substituted divalent hydrocarbon group having 1 to 18 carbon atoms, n represents each independently a number of 0 to 50, and m represents each Independently represents a number from 0 to 50.)

<3> The content of the addition reaction product of the (A1) epoxy resin and (meth) acrylic acid is 5% by mass or more based on the total amount of the compound (A) having an ethylenically unsaturated double bond. The pre-supplied underfill material according to <1> or <2>.

<4> Any one of <1> to <3>, wherein the (D) flexible agent includes (D1) a compound having a structural unit represented by the following general formula (I-7) or (I-8) The pre-supplied underfill material according to Item 1.

(In General Formula (I-7), R ⁷¹ and R ⁷² each independently represent a hydrogen atom or a methyl group, and R ⁷³ and R ⁷⁴ each independently have 1 carbon atom which may have a substituent. -18 represents a monovalent hydrocarbon group, p and q each independently represent a positive number, provided that R ⁷³ and R ⁷⁴ are different from each other, R ⁷³ and R ⁷⁴ are each independently It may be denatured.)

(In General Formula (I-8), R ⁸¹ , R ⁸² , and R ⁸³ each independently represent a hydrogen atom or a methyl group, and R ⁸⁴ , R ⁸⁵ , and R ⁸⁶ each independently have a substituent. represents a monovalent hydrocarbon group of good 1 to 18 carbon atoms have been, x, y, and z each independently represent a positive number. ^However, different from each other and ^{R 84} and ^{R 85, R 85} And R ⁸⁶ are different from each other, and R ⁸⁴ , R ⁸⁵ , and R ⁸⁶ may each independently be partially modified.)

<5> The compound (D1) having a structural unit represented by the general formula (I-7) or (I-8) has a weight average molecular weight of 5,000 to 1,000,000 in <4>. The previously supplied underfill material as described.

<6> The content ratio of the compound represented by (D1) general formula (I-7) or (I-8) is 1% by mass or more based on the total amount of the pre-feed type underfill material <4>. Or the pre-feed type underfill material as described in <5>.

<7> The compound according to any one of <1> to <6>, wherein the compound (A) having an ethylenically unsaturated double bond includes a compound having two or more ethylenically unsaturated double bonds in one molecule. The pre-feed type underfill material described in 1.

<8> The content of the compound having two or more ethylenically unsaturated double bonds in one molecule is 30% by mass or more based on the total amount of the compound (A) having an ethylenically unsaturated double bond. The pre-supplied underfill material according to <7>.

<9> The tip according to any one of <1> to <8>, wherein the compound (A) having an ethylenically unsaturated double bond includes (A2) tricyclodecane dimethylol di (meth) acrylate. Supply type underfill material.

<10> The content of the (A2) tricyclodecane dimethylol di (meth) acrylate is 20% by mass or more based on the total amount of the compound (A) having an ethylenically unsaturated double bond. <9> The pre-feed type underfill material described in 1.

<11> Any of <1> to <10>, wherein the compound (A) having an ethylenically unsaturated double bond includes (A3) a (meth) acrylate compound represented by the following general formula (I-2) The pre-feed type underfill material according to claim 1.

(In General Formula (I-2), each R ²¹ independently represents a hydrogen atom or a methyl group, and R ²² represents a C 1-18 divalent hydrocarbon group which may have a substituent. And r and s each independently represent a number from 0 to 50.)

<12> The content of the (meth) acrylate compound represented by (A3) general formula (I-2) is 10% by mass with respect to the total amount of the compound (A) having an ethylenically unsaturated double bond. The pre-supplied underfill material according to <11> as described above.

<13> The pre-feed type underfill material according to any one of <1> to <12>, wherein the (B) reaction initiator includes an organic peroxide.

<14> The pre-feed type underfill material according to any one of <1> to <13>, wherein the volume average particle diameter of the (C) inorganic filler is 0.1 μm to 10 μm.

<15> The pre-feed type according to any one of <1> to <14>, wherein the content of the inorganic filler (C) is 10% by mass or more based on the total amount of the pre-feed type underfill material. Underfill material.

<16> Any one of <1> to <15>, on at least one surface selected from the group consisting of a surface facing the wiring board in the electronic component and a surface facing the electronic component in the wiring board A supply step of supplying the pre-supplied underfill material according to claim 1;
A method for manufacturing an electronic component device, comprising: a connecting step of connecting the electronic component and the wiring board through a connecting portion and curing the pre-supplied underfill material after the supplying step.

<17> Electronic components,
A wiring board that is disposed opposite to the electronic component and connected to the electronic component via a connection portion;
The electronic component apparatus which has a hardened | cured material of the pre-feed type underfill material of any one of <1>-<15> arrange | positioned between the said electronic component and the said wiring board.

  According to the present invention, it is possible to shorten the curing time, the generation of voids, and the pre-feed type underfill material that is excellent in adhesiveness with an electronic component, and the electrical connection using the pre-feed type underfill material It is possible to provide an electronic component device manufacturing method capable of manufacturing an electronic component device excellent in reliability, and an electronic component device excellent in electrical connection reliability and generating less voids.

It is a figure explaining the process of the manufacturing method of the electronic component apparatus by a prior supply system.

  Hereinafter, an example of an embodiment of a pre-supplied underfill material, an electronic component device manufacturing method, and an electronic component device to which the present invention is applied will be described in detail with reference to the drawings. 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. The same applies to numerical values and ranges thereof, and the present invention is not limited thereto.

In this specification, the term “process” includes a process that is independent of other processes and includes the process if the purpose of the process is achieved even if it cannot be clearly distinguished from the other processes. It is.
In the present specification, the numerical ranges indicated by using “to” include numerical values described before and after “to” as the minimum value and the maximum value, respectively.
In the numerical ranges described stepwise in this specification, the upper limit value or the lower limit value described in one numerical range may be replaced with the upper limit value or the lower limit value of another numerical range. Good. Further, in the numerical ranges described in this specification, the upper limit value or the lower limit value of the numerical range may be replaced with the values shown in the examples.
In the present specification, the content of each component in the composition is the sum of the plurality of substances present in the composition unless there is a specific indication when there are a plurality of substances corresponding to each component in the composition. It means the content rate of.
In the present specification, the particle diameter of each component in the composition is a mixture of the plurality of types of particles present in the composition unless there is a specific indication when there are a plurality of types of particles corresponding to each component in the composition. Means the value of.

In this specification, “room temperature” means 25 ° C.
In the present specification, “liquid” means a substance that exhibits fluidity and viscosity and has a viscosity of 0.0001 Pa · s to 1000 Pa · s at 25 ° C., which is a measure of viscosity.
In this specification, the “underfill material” is an electronic component device (flip chip) formed by bump-connecting an electronic component on a wiring board having a ceramic, glass epoxy resin, glass imide resin, polyimide film or the like as a substrate. It means a material that fills the gap (gap) between the bump-connected electronic component and the wiring board and protects the connection between the electronic component and the wiring board from temperature, humidity, and mechanical external force.
In the present specification, the “viscosity of the underfill material” is defined as a value when an underfill material kept at 25 ° C. is measured with a rheometer at a shear rate of 5.0 s ⁻¹ . Specifically, the “viscosity” is measured as a shear viscosity at a temperature of 25 ° C. using a rotary rheometer equipped with a cone plate (diameter 40 mm, cone angle 0 °).
In this specification, “(meth) acrylic acid” means at least one of acrylic acid and methacrylic acid, and “(meth) acrylic compound” means at least one of acrylic compound and methacrylic compound, and “( “Meth) acrylate” means at least one of acrylate and methacrylate, and “(meth) acryloyl” means at least one of acryloyl and methacryloyl.

[Pre-supplied underfill material]
The pre-supplied underfill material of the present embodiment (hereinafter, also simply referred to as “underfill material of the present embodiment”) includes (A) a compound having an ethylenically unsaturated double bond, (B) a reaction initiator, (C) An inorganic filler and (D) a flexible agent, and (A) a compound having an ethylenically unsaturated double bond is an addition reaction product of (A1) an epoxy resin and (meth) acrylic acid. Including.

The underfill material of the present embodiment can reduce the curing time of the underfill material by adopting the above-described configuration, generates less voids (that is, has low void properties), and adheres to electronic components. A cured product having excellent properties can be obtained. The cured product can improve the connection reliability of the electronic component device.
The reason is not clear, but is presumed as follows.

The compound (A) having an ethylenically unsaturated double bond contained in the underfill material of this embodiment is cured by a radical polymerization reaction. The radical polymerization reaction has a higher reaction rate than the epoxy ring-opening reaction. Therefore, it is speculated that the underfill material of the present embodiment has a higher reaction speed than the conventional underfill material containing an epoxy resin and an epoxy resin curing agent, and can shorten the curing time. By shortening the curing time of the underfill material, it is considered that generation of voids caused by volatile matter generated from the underfill material or the like can be suppressed.
Moreover, the underfill material of this embodiment improves adhesiveness with a base material by containing the addition reaction product of (D) a flexible agent and (A1) epoxy resin and (meth) acrylic acid. Can do. This is because (D) containing a flexible agent reduces curing shrinkage and thermal expansion and contraction of the cured product, and (A1) contains a secondary hydroxyl group in the addition reaction product of epoxy resin and (meth) acrylic acid. This is probably because the adhesive force can be increased. Furthermore, by improving the adhesion to the base material, it is possible to suppress the peeling between the underfill material and the electronic component device, and to prevent the electrical connectivity between the electronic component and the wiring board from being impaired. And it is thought that the connection reliability of an electronic component apparatus can be improved.

  The viscosity of the underfill material of the present embodiment is, for example, preferably 0.01 Pa · s to 1000 Pa · s at 25 ° C., more preferably 0.1 Pa · s to 500 Pa · s, and 1.0 Pa. -More preferably, it is s-100Pa.s. The method for measuring the viscosity of the underfill material in the present embodiment is as described above.

Moreover, it is preferable that it is 0.1-100, for example, it is more preferable that it is 0.5-50, and it is still more preferable that it is 1-10. In addition, the measuring method of the change index of the underfill material in the present embodiment is as follows.
For underfill material that was kept at 25 ° C., the value measured respectively at a shear rate of shear rate and 0.5 s ^-1 of 5.0 s ^-1 using a rheometer ratio (shear rate 0.5 s ^- Viscosity when measured at ¹ ) / (viscosity when measured at a shear rate of 5.0 s ⁻¹ ) is defined as a thixotropic index. The viscosity at a shear rate viscosity and 0.5 s ^-1 at a shear rate of 5.0 s ^-1, using a rotary shear viscometer equipped with a cone plate (diameter 40 mm, cone angle 0 °), 25 The value measured at ° C.

  Hereinafter, the essential and optional components contained in the underfill material of the present embodiment will be described.

<(A) Compound having an ethylenically unsaturated double bond>
The underfill material of the present embodiment contains (A) a compound having an ethylenically unsaturated double bond (hereinafter also referred to as “component (A)”), and the compound having the ethylenically unsaturated double bond. (A1) addition reaction product of epoxy resin and (meth) acrylic acid (hereinafter also referred to as “compound (A1)”). A compound (A1) may be used individually by 1 type, and may be used in combination of 2 or more type.
The ethylenically unsaturated double bond is not particularly limited as long as it is a functional group capable of radical reaction using (B) a reaction initiator, and is a (meth) acryloyl group from the viewpoint of reactivity. It is preferable that it is a (meth) acryloyloxy group.

((A1) addition reaction product of epoxy resin and (meth) acrylic acid)
The epoxy resin that can be used to obtain the compound (A1) is not particularly limited as long as it is an epoxy resin having two or more epoxy groups in one molecule. Examples of the epoxy resin include glycidyl ether type epoxy resins obtained by reaction of bisphenol A, bisphenol F, bisphenol AD, bisphenol S, naphthalene diol, hydrogenated bisphenol A and the like with epichlorohydrin; orthocresol novolac type epoxy resins. A novolak-type epoxy resin obtained by epoxidizing a novolak resin obtained by condensation or copolymerization of a phenol compound and an aldehyde compound; a glycidyl ester-type epoxy obtained by reacting a polybasic acid such as phthalic acid or dimer acid with epichlorohydrin Resin; Glycidylamine type epoxy resin obtained by reaction of amine compound such as p-aminophenol, diaminodiphenylmethane, isocyanuric acid and epichlorohydrin; Resulting bond is oxidized with a peracid such as peracetic acid linear aliphatic epoxy resins and alicyclic epoxy resins; and epoxy resins having a resorcinol skeleton. As an epoxy resin, these may be used individually by 1 type, and may be used in combination of 2 or more type.

  The method for obtaining the compound (A1) is not particularly limited. As a method for obtaining the compound (A1), for example, a method in which a predetermined amount of epoxy resin and (meth) acrylic acid are subjected to an addition reaction at room temperature; a method in which each material is heated to undergo an addition reaction; a solvent is added to each material. In addition, a method of addition reaction; and a method of adding a general reaction catalyst (for example, a Lewis base such as amines and phosphines or a salt thereof) to each material and causing the addition reaction are included.

  The ratio of the epoxy resin and (meth) acrylic acid in obtaining the compound (A1) is not particularly limited. From the viewpoint of suppressing the unreacted substances of the epoxy resin and (meth) acrylic acid to be small, for example, the equivalent number of the carboxy group of (meth) acrylic acid is 0.3 equivalent to 1 equivalent of epoxy group of epoxy resin It is preferably set in the range of 10.0 equivalents, more preferably set in the range of 0.5 equivalents to 5.0 equivalents, and still more preferably set in the range of 0.8 equivalents to 3.0 equivalents. .

  The number of ethylenically unsaturated double bonds in one molecule of the compound (A1) is, for example, 1 to 8 from the viewpoint of adhesion between the cured product of the underfill material and the cured shrinkage of the cured product. It is preferable, it is more preferable that it is 1-6, and it is still more preferable that it is 1-4.

  The compound (A1) is preferably a compound represented by the following general formula (I-1).

(In General Formula (I-1), R ¹¹ each independently represents a hydrogen atom or a methyl group, R ¹² each independently represents a C 1-18 divalent hydrocarbon group, and R ¹³ is Represents a C1-C18 divalent hydrocarbon group which may have a substituent, each n independently represents a number of 0 to 50, and each m independently represents a number of 0 to 50; Represents.)

In the general formula (I-1), the divalent hydrocarbon group having 1 to 18 carbon atoms which may have a substituent represented by R ¹² is a divalent aliphatic carbon group having 1 to 18 carbon atoms. It is preferably a hydrogen group, a divalent alicyclic hydrocarbon group having 3 to 18 carbon atoms, or a divalent aromatic hydrocarbon group having 6 to 18 carbon atoms.
The carbon number of the divalent hydrocarbon group having 1 to 18 carbon atoms does not include the carbon number of the substituent.

The divalent aliphatic hydrocarbon group having 1 to 18 carbon atoms represented by R ¹² is preferably a divalent aliphatic hydrocarbon group having 1 to 14 carbon atoms, and is a divalent aliphatic group having 1 to 10 carbon atoms. More preferably, it is an aliphatic hydrocarbon group.
Examples of the divalent aliphatic hydrocarbon group having 1 to 18 carbon atoms include methylene group, ethylene group, propylene group, isopropylene group, butylene group, pentylene group, hexylene group, octylene group, decylene group, dodecylene group, Examples include vinylene group, ethylidene group, vinylidene group, propenylene group, and butadienylene group. The divalent aliphatic hydrocarbon group having 1 to 18 carbon atoms is preferably a methylene group, an ethylene group, a propylene group, an isopropylene group, a butylene group, or a hexylene group, and a methylene group, an ethylene group, a propylene group, or an isopropylene group. A group or a butylene group is more preferable.

The C 3-18 divalent alicyclic hydrocarbon group represented by R ¹² is preferably a C 3-14 divalent alicyclic hydrocarbon group, and has 5 to 12 carbon atoms. It is more preferably a divalent alicyclic hydrocarbon group.
Examples of the divalent alicyclic hydrocarbon group having 3 to 18 carbon atoms include a cyclopentylene group, a cyclohexylene group, a cycloheptylene group, a cyclopentenylene group, a cyclohexenylene group, and a cyclohexylidene group. It is done.

The divalent aromatic hydrocarbon group having 6 to 18 carbon atoms represented by R ¹² is preferably a divalent aromatic hydrocarbon group having 6 to 14 carbon atoms, and is divalent having 6 to 12 carbon atoms. The aromatic hydrocarbon group is more preferable.
Examples of the divalent aromatic hydrocarbon group having 6 to 18 carbon atoms include a phenylene group, a biphenylene group, and a terphenylene group.

Among them, R ¹² in the general formula (I-1) may have a substituent, a divalent aliphatic hydrocarbon group having 1 to 18 carbon atoms or a divalent aromatic group having 6 to 18 carbon atoms. It is more preferably a hydrocarbon group, and further preferably a divalent aliphatic hydrocarbon group having 1 to 18 carbon atoms which may have a substituent.

Examples of the substituent that R ¹² in General Formula (I-1) may have include an alkyl group, an alkoxy group, an aryl group, an aryloxy group, a hydroxyl group, an amino group, a halogen atom, a methacryloyloxy group, and a mercapto group. Groups, imino groups, ureido groups, and isocyanate groups. R ¹² preferably has no substituent.

In the general formula (I-1), the divalent hydrocarbon group having 1 to 18 carbon atoms which may have a substituent represented by R ¹³ is a divalent aliphatic carbon group having 1 to 18 carbon atoms. 6 carbon atoms having a hydrogen group, a divalent alicyclic hydrocarbon group having 3 to 18 carbon atoms, a divalent aromatic hydrocarbon group having 6 to 18 carbon atoms, or both an aliphatic group and an aromatic group A divalent hydrocarbon group of ˜18 is preferable.
The carbon number of the divalent hydrocarbon group having 1 to 18 carbon atoms does not include the carbon number of the substituent.

A divalent aliphatic hydrocarbon group having 1 to 18 carbon atoms, a divalent alicyclic hydrocarbon group having 3 to 18 carbon atoms, and a divalent aromatic carbon group having 6 to 18 carbon atoms, represented by R ¹³ A hydrogen group is synonymous with R < ¹² > in general formula (I-1).
The divalent hydrocarbon group having 6 to 18 carbon atoms having both the aliphatic group and the aromatic group represented by R ¹³ is preferably a divalent hydrocarbon group having 8 to 18 carbon atoms, A divalent hydrocarbon group having 10 to 18 carbon atoms is more preferable.
Examples of the C6-C18 divalent hydrocarbon group having both an aliphatic group and an aromatic group include a methylene bisphenylene group, an ethylene bisphenylene group, a propylene bisphenylene group, a monomethylmethylene bisphenylene group, Examples include dimethylmethylene bisphenylene group, phenylene bisethylene group, and phenylenemethylene group.

Among them, R ¹³ in the general formula (I-1) may have a substituent, a divalent aliphatic hydrocarbon group having 1 to 18 carbon atoms, or a divalent aromatic group having 6 to 18 carbon atoms. It is more preferably a hydrocarbon group or a divalent hydrocarbon group having 6 to 18 carbon atoms having both an aliphatic group and an aromatic group, and a methylene group, an ethylene group, a monomethylmethylene group, a dimethylmethylene group, More preferred is a biphenyl group or a dimethylmethylenebisphenylene group.

Examples of the substituent that R ¹³ in the general formula (I-1) may have include an alkyl group, an alkoxy group, an aryl group, an aryloxy group, a hydroxyl group, an amino group, a halogen atom, a methacryloyloxy group, and a mercapto group. Groups, imino groups, ureido groups, and isocyanate groups. R ¹³ preferably has no substituent.

In general formula (I-1), n represents the number of 0-50 each independently. From the viewpoint of the flexibility of the cured product of the underfill material, n preferably represents a number from 0 to 30, and more preferably represents a number from 0 to 20.
In general formula (I-1), m represents the number of 0-50 each independently. From the viewpoint of flexibility of the cured product of the underfill material, m preferably represents a number from 0 to 30, and more preferably represents a number from 0 to 20.
In addition, although n and m which are the number of structural units in a parenthesis show an integer value about a single molecule | numerator, they show the rational number which is an average value as an aggregate | assembly of a some kind of molecule | numerator.

In the compound represented by the general formula (I-1), R ¹¹ is each independently a hydrogen atom or a methyl group, and R ¹² is each independently a divalent aliphatic hydrocarbon group having 1 to 18 carbon atoms. R ¹³ is a divalent aliphatic hydrocarbon group having 1 to 18 carbon atoms, a divalent aromatic hydrocarbon group having 6 to 18 carbon atoms, or a carbon number having both an aliphatic group and an aromatic group. A compound having 6 to 18 divalent hydrocarbon groups, each of n independently represents a number of 0 to 50, and each of m independently represents a number of 0 to 50 is preferable.

The compound represented by the general formula (I-1), R ¹¹ are each independently a hydrogen atom or a methyl group, a divalent aliphatic hydrocarbon having 1 to 12 carbon atoms R ¹² are each independently R ¹³ is a divalent aliphatic hydrocarbon group having 1 to 12 carbon atoms, a divalent aromatic hydrocarbon group having 10 to 18 carbon atoms, or both an aliphatic group and an aromatic group. A compound having a carbon number of 6 to 18 and having n of 0 to 30 and m independently of 0 to 30 is more preferable.

Moreover, as a compound represented by general formula (I-1), R < ¹¹ > is a hydrogen atom or a methyl group, and R < ¹² > is a C1-C6 bivalent aliphatic hydrocarbon group each independently. , R ¹³ is a methylene group, ethylene group, monomethylmethylene group, dimethylmethylene group, biphenyl group, or dimethylmethylenebisphenylene group, n is independently a number from 0 to 20, and m is independently 0 to 0. More preferred are compounds representing the number 20.

As a compound (A1) which can be obtained as a commercial item, the following are mentioned, for example.
An addition reaction product of ethylene glycol diglycidyl ether (Kyoeisha Chemical Co., Ltd., trade name “Epolite 40E”) and methacrylic acid, the main component is the general formula (I-1), and R ¹¹ is a methyl group A compound in which n is 0, m is 0, and R ¹³ is an ethylene group (Kyoeisha Chemical Co., Ltd., trade name “epoxy ester 40EM”)
-An addition reaction product of propylene glycol diglycidyl ether (Kyoeisha Chemical Co., Ltd., trade name "Epolite 70P") and acrylic acid, the main component is the general formula (I-1), and R ¹¹ is a hydrogen atom A compound in which n is 0, m is 0, and R ¹³ is an isopropylene group (Kyoeisha Chemical Co., Ltd., trade name “epoxy ester 70PA”)
-An addition reaction product of tripropylene glycol diglycidyl ether (Kyoeisha Chemical Co., Ltd., trade name “Epolite 200P”) and acrylic acid, the main component of which is general formula (I-1), and R ¹¹ is all hydrogen A compound in which R ¹² is an isopropylene group, n is 0, m is 1 and R ¹³ is an isopropylene group (Kyoeisha Chemical Co., Ltd., trade name “epoxy ester 200PA”) ")
-An addition reaction product of glycerin diglycidyl ether (Kyoeisha Chemical Co., Ltd., trade name "Epolite 80MF") and acrylic acid, the main component is the general formula (I-1), and R ¹¹ is a hydrogen atom. A compound in which n is 0, m is 0, and R ¹³ is a 2-hydroxypropylene group (Kyoeisha Chemical Co., Ltd., trade name “epoxy ester 80MFA”)
-It is an addition reaction product of diglycidyl ether (Kyoeisha Chemical Co., Ltd., trade name "Epolite 3002N") obtained by adding 2 mol of propylene oxide to bisphenol A and methacrylic acid, and the main component is represented by the general formula (I-1) Compounds in which R ¹¹ is a methyl group, R ¹² is an isopropylene group, n is 0, m is 1 and R ¹³ is a dimethylmethylenebisphenylene group (Kyoeisha) Chemical Co., Ltd., trade name “Epoxy ester 3002M (N)”)
-An addition reaction product of diglycidyl ether obtained by adding 2 mol of propylene oxide to bisphenol A (Kyoeisha Chemical Co., Ltd., trade name "Epolite 3002N") and acrylic acid, and the main component is represented by the general formula (I-1): Compounds in which R ¹¹ is a hydrogen atom, R ¹² is an isopropylene group, n is 0, m is 1 and R ¹³ is a dimethylmethylenebisphenylene group (Kyoeisha) Chemical Co., Ltd., trade name “Epoxyester 3002A (N)”)
-It is an addition reaction product of bisphenol A diglycidyl ether and methacrylic acid, and the main component is R ¹¹ in the general formula (I-1), each n is 0, n is 0, and m is A compound in which both are 0 and R ¹³ is a dimethylmethylenebisphenylene group (Kyoeisha Chemical Co., Ltd., trade name “epoxy ester 3000MK”)
An addition reaction product of bisphenol A diglycidyl ether and acrylic acid, and the main component is R ¹¹ in the general formula (I-1), each n is 0, n is 0, and m is A compound in which both are 0 and R ¹³ is a dimethylmethylenebisphenylene group (Kyoeisha Chemical Co., Ltd., trade name “epoxy ester 3000A”)
A compound (di-Nakamura Chemical Co., Ltd., trade name “EA-1010”, which is an addition reaction product of diglycidyl ether having a bisphenol A skeleton and acrylic acid, and the number of functional groups of the acryloyl group in the oligomer is 1-2. series)
・ Compound that is an addition reaction product of diglycidyl ether having bisphenol A skeleton and acrylic acid, in which the number of functional groups of acryloyl group in the oligomer is 2 (Shin-Nakamura Chemical Co., Ltd., trade name “EA-1020” series)
-An addition reaction product of glycidyl ether having a phenol novolak skeleton and acrylic acid, a compound in which the number of functional groups of the acryloyl group in the oligomer is 5 to 6, and 20% by mass of PGMAC (propylene glycol monomethyl ether acetate) Containing mixture (Shin-Nakamura Chemical Co., Ltd., trade name “EA-6320 / PGMAC”)
-A mixture of a glycidyl ether having a phenol novolak skeleton and acrylic acid, containing a compound having 5 to 6 functional groups of acryloyl groups in the oligomer and 30% by mass of PGMAC (Shin Nakamura Chemical) Kogyo Co., Ltd., trade name “EA-6340 / PGMAC”)
A mixture containing glycidyl ether having a cresol novolak skeleton and acrylic acid, containing a compound having 5 to 6 functional groups of acryloyl groups in the oligomer and 30% by mass of PGMAC (Shin Nakamura Chemical) Kogyo Co., Ltd., trade name “EA-7120 / PGMAC”)
-A mixture which is an acid-modified product of the above-mentioned trade name "EA-7120 / PGMAC" (Shin Nakamura Chemical Co., Ltd., trade name "EA-7140 / PGMAC")
・ A mixture of the above-mentioned trade name “EA-7120 / PGMAC” which is a high molecular weight type (Shin Nakamura Chemical Co., Ltd., trade name “EA-7420 / PGMAC”)

  The molecular weight of the compound (A1) is, for example, preferably from 100 to 10,000, more preferably from 200 to 5,000, and more preferably from 300 to 3,000, from the viewpoint of the strength and flexibility of the cured product of the underfill material. Is more preferable.

  The content of the compound (A1) is, for example, preferably 5% by mass or more and more preferably 10% by mass or more with respect to the total amount of the component (A). When the content of the compound (A1) is 5% by mass or more, the cured product of the underfill material tends to be excellent in adhesiveness with the electronic component. This content rate may be usually 50% by mass or less, or 40% by mass or less.

(Other compounds having an ethylenically unsaturated double bond)
The underfill material of this embodiment may contain a compound having an ethylenically unsaturated double bond other than the compound (A1) as the component (A). Examples of the other compound having an ethylenically unsaturated double bond include known compounds used in underfill materials used for manufacturing electronic component devices.
Other compounds having an ethylenically unsaturated double bond may be used singly or in combination of two or more.

  As another compound having an ethylenically unsaturated double bond, a compound having an ethylenically unsaturated double bond that is liquid at room temperature may be used so that the underfill material of the present embodiment is liquid at room temperature. A compound having an ethylenically unsaturated double bond that is solid at room temperature and a compound having an ethylenically unsaturated double bond that is liquid at room temperature may be used in combination.

  As other compounds having an ethylenically unsaturated double bond, even a compound having only one ethylenically unsaturated double bond in one molecule has 2 ethylenically unsaturated double bonds in one molecule. It may be a compound having more than one. In the following, the case of having only one ethylenically unsaturated double bond in one molecule is referred to as monofunctional, the case of having two ethylenically unsaturated double bonds in one molecule is referred to as bifunctional, The case where three or more ethylenically unsaturated double bonds are present in one molecule is sometimes referred to as polyfunctional.

  Examples of other compounds having an ethylenically unsaturated double bond include one or more compounds selected from the group consisting of (meth) acrylic compounds, allyl nadiimide compounds, and maleimide compounds, and (meth) An acrylic compound or an allyl nadiimide compound is preferable, and a (meth) acrylic compound is more preferable.

As the (meth) acryl compound, a compound having one or more (meth) acryloyl groups in one molecule is preferable from the viewpoint of reactivity, and a compound having two or more (meth) acryloyl groups in one molecule is preferable. More preferred. Moreover, as a (meth) acryl compound, the compound which has 10 or less (meth) acryloyl groups in 1 molecule from a flexible viewpoint of the hardened | cured material of an underfill material is preferable, and 6 or less per molecule A compound having a (meth) acryloyl group is more preferable. The (meth) acryloyl group is preferably a (meth) acryloyloxy group.
The (meth) acrylic compound is more preferably a di (meth) acrylate having an alicyclic hydrocarbon group from the viewpoint of low voids and strength of the cured product of the underfill material.

Specific examples of (meth) acrylic compounds include methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, t-butyl acrylate, amyl acrylate, isoamyl acrylate, hexyl acrylate, heptyl acrylate, octyl acrylate. 2-ethylhexyl acrylate, nonyl acrylate, decyl acrylate, isodecyl acrylate, lauryl acrylate, tridecyl acrylate, hexadecyl acrylate, stearyl acrylate, isostearyl acrylate, cyclohexyl acrylate, isobornyl acrylate, 2-hydroxyethyl acrylate, 2- Hydroxypropyl acrylate, Dimergio Monoacrylate, diethylene glycol acrylate, polyethylene glycol acrylate, polypropylene glycol acrylate, 2-methoxyethyl acrylate, 2-ethoxyethyl acrylate, 2-butoxyethyl acrylate, methoxydiethylene glycol acrylate, methoxypolyethylene glycol acrylate, 2-phenoxyethyl acrylate, phenoxydiethylene glycol acrylate , Phenoxy polyethylene glycol acrylate, 2-benzoyloxyethyl acrylate, 2-hydroxy-3-phenoxypropyl acrylate, benzyl acrylate, 2-cyanoethyl acrylate, γ-acryloxypropyltrimethoxysilane, glycidyl acrylate, 4-hydroxybutyl Acrylate glycidyl ether, tetrahydrofurfuryl acrylate, dicyclopentenyloxyethyl acrylate, dicyclopentanyl acrylate, dicyclopentenyl acrylate, tetrahydropyranyl acrylate, dimethylaminoethyl acrylate, diethylaminoethyl acrylate, 1,2,2,6,6-pentamethylpiperidinyl acrylate, 2,2,6,6-tetramethylpiperidinyl acrylate, acryloxyethyl phosphate, acryloxyethyl phenyl acid phosphate, β-acryloyloxyethyl hydro Monofunctional acrylic compounds such as genphthalate, β-acryloyloxyethyl hydrogen succinate, 2-acryloyloxyethyl-2-hydroxyethyl-phthalic acid,
Pentenyl diacrylate, tetrahydrofurfuryl diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, polypropylene glycol diacrylate, trimethylolpropane diacrylate, 1,4-butanediol diacrylate 1,6-hexanediol diacrylate, ethylene oxide modified neopentyl glycol diacrylate, tricyclodecane dimethylol diacrylate, ethylene oxide modified bisphenol F type diacrylate, ethylene oxide modified bisphenol A type diacrylate, propylene oxide modified bisphenol A Type diacrylate and other bifunctional acrylic compounds ,
A polyfunctional acrylic compound such as trimethylolpropane triacrylate, ditrimethylolpropane tetraacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, triacrylate of tris (β-hydroxyethyl) isocyanurate,
Reaction product of hydroxyethyl (meth) acrylate and 2,5-bis (isocyanatomethyl) -bicyclo [2.2.1] heptane, hydroxyethyl (meth) acrylate and 2,6-bis (isocyanatomethyl) -bicyclo [2.2.1] Reaction product of heptane, reaction product of hydroxyethyl (meth) acrylate and 2,4-tolylene diisocyanate, reaction product of hydroxyethyl (meth) acrylate and isophorodiisocyanate, Reaction product of hydroxypropyl (meth) acrylate and 2,4-tolylene diisocyanate, reaction product of hydroxypropyl (meth) acrylate and isophorodiisocyanate, reaction of phenylglycidyl ether (meth) acrylate and hexamethylene diisocyanate Generation , Reaction product of phenylglycidyl ether and toluene diisocyanate, reaction product of pentaerythritol tri (meth) acrylate and hexamethylene diisocyanate, reaction product of pentaerythritol tri (meth) acrylate and toluene diisocyanate, pentaerythritol tri ( A compound having an isocyanate group such as a reaction product of (meth) acrylate and isophorodiisocyanate, a reaction product of dipentaerythritol penta (meth) acrylate and hexamethylene diisocyanate, and an ethylenically unsaturated double bond in one molecule and A compound having an ethylenically unsaturated double bond and a urethane bond in one molecule, obtained by a condensation reaction with a compound having a hydroxyl group,
A monofunctional acrylic compound, a bifunctional acrylic compound, a polyfunctional acrylic compound, or a methacrylic compound in which the acryloyl group of a compound having an ethylenically unsaturated double bond and a urethane bond in one molecule is substituted with a methacryloyl group, etc. Is mentioned.

  As an allyl nadiimide compound, the allyl nadiimide compound represented by the following general formula (I-4) is mentioned.

(In the general formula (I-4), R ⁴¹ represents a C 1-18 divalent hydrocarbon group which may have a substituent.)

In the general formula (I-4), the divalent hydrocarbon group which may have a substituent represented by R ⁴¹ is a divalent aliphatic hydrocarbon group having 1 to 18 carbon atoms, 3 carbon atoms. A divalent alicyclic hydrocarbon group having 18 to 18 carbon atoms, a divalent aromatic hydrocarbon group having 6 to 18 carbon atoms, or a divalent hydrocarbon having 6 to 18 carbon atoms having both an aliphatic group and an aromatic group. It is preferably a hydrocarbon group. R ⁴¹ in the general formula (I-4) has the same meaning as R ¹³ in the general formula (I-1), and the preferred range is also the same.

  As the allyl nadiimide compound represented by the general formula (I-4), for example, bis {4- (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide) phenyl} methane (Maruzen Petrochemical Co., Ltd., trade name “BANI-M”) and N, N′-m-xylylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide) (Maruzen Petrochemical Co., Ltd., trade name “BANI-X”) is commercially available.

  As a maleimide compound, the maleimide compound represented by the following general formula (I-5) or (I-6) is mentioned.

(In the general formula (I-5), R ⁵¹ represents a C 1-18 divalent hydrocarbon group which may have a substituent.)

(In general formula (I-6), t represents a number of 0 or more.)

In the general formula (I-5), the divalent hydrocarbon group having 1 to 18 carbon atoms which may have a substituent represented by R ⁵¹ is a divalent aliphatic carbon group having 1 to 18 carbon atoms. 6 carbon atoms having a hydrogen group, a divalent alicyclic hydrocarbon group having 3 to 18 carbon atoms, a divalent aromatic hydrocarbon group having 6 to 18 carbon atoms, or both an aliphatic group and an aromatic group A divalent hydrocarbon group of ˜18 is preferable. R ⁵¹ in formula (I-5) has the same definition as R ¹³ in formula (I-1), and the preferred range is also the same.

  Examples of the bismaleimide compound represented by the general formula (I-5) include 4,4′-diphenylmethane bismaleimide (Daiwa Kasei Kogyo Co., Ltd., trade name “BMI-1000”), m-phenylene bismaleimide (Daiwa Kasei). Industrial Co., Ltd., trade name “BMI-3000”), bisphenol A diphenyl ether bismaleimide (Daiwa Kasei Kogyo Co., Ltd., trade name “BMI-4000”), 3,3′-dimethyl-5,5′-diethyl-4, 4′-diphenylmethane bismaleimide (Daiwa Kasei Kogyo Co., Ltd., trade name “BMI-5100”), 4-methyl-1,3-phenylene bismaleimide (Daiwa Kasei Kogyo Co., Ltd., trade name “BMI-7000”), and 1,6′-bismaleimide- (2,2,4-trimethyl) hexane (Daiwa Kasei Kogyo Co., Ltd., commodity) "BMI-TMH") is available as a commercial product.

In general formula (I-6), t preferably represents a number from 0 to 10, and more preferably represents a number from 0 to 5. Note that t, which is the number of structural units in parentheses, represents an integer value for a single molecule, but a rational number that is an average value as an aggregate of a plurality of types of molecules.
As the bismaleimide compound represented by the general formula (I-6), for example, phenylmethanemaleimide (Daiwa Kasei Kogyo Co., Ltd., trade name “BMI-2000”) is commercially available.

  Component (A) in the present embodiment is a compound having another ethylenically unsaturated double bond from the viewpoint of adhesion to electronic component devices and low voids of a cured product of the underfill material, among the above compounds, It is preferable to include a compound having two or more ethylenically unsaturated double bonds in one molecule.

  The content of the compound having two or more ethylenically unsaturated double bonds in one molecule is preferably, for example, 30% by mass or more, and 40% by mass or more with respect to the total amount of the component (A). Is more preferable, and it is still more preferable that it is 50 mass% or more. If the content of the compound having two or more ethylenically unsaturated double bonds is 30% by mass or more, the adhesiveness and low void property of the cured product of the underfill material tend to be improved. The content of the compound having two or more ethylenically unsaturated double bonds in one molecule is preferably 95% by mass or less, and 90% by mass or less, based on the total amount of the component (A). More preferred.

  As a compound having two or more ethylenically unsaturated double bonds in one molecule, it is more preferable to include the above-mentioned bifunctional (meth) acrylic compound, and (A2) tricyclodecane dimethylol di (meth) acrylate ( (Hereinafter also referred to as “compound (A2)”) and (A3) selected from the group consisting of (meth) acrylate compounds represented by the following general formula (I-2) (hereinafter also referred to as “compound (A3)”). More preferably, one or more of them are included.

(In General Formula (I-2), each R ²¹ independently represents a hydrogen atom or a methyl group, and R ²² represents a C 1-18 divalent hydrocarbon group which may have a substituent. And r and s each independently represent a number from 0 to 50.)

In the general formula (I-2), the divalent hydrocarbon group having 1 to 18 carbon atoms which may have a substituent represented by R ²² is a divalent aliphatic carbon group having 1 to 18 carbon atoms. It is preferably a hydrogen group, a divalent alicyclic hydrocarbon group having 3 to 18 carbon atoms, or a divalent aromatic hydrocarbon group having 6 to 18 carbon atoms. R < ²² > in general formula (I-2) is synonymous with R < ¹² > in general formula (I-1), and its preferable range is also the same.
In general formula (I-2), r and s each independently preferably represent a number of 1 to 40, and more preferably represent a number of 1 to 30. In addition, although r and s which are the number of structural units in a parenthesis show an integer value about a single molecule | numerator, they show the rational number which is an average value as an aggregate | assembly of multiple types of molecule | numerator.

  When the compound (A2) is used as a compound having two or more ethylenically unsaturated double bonds in one molecule, the content of the compound (A2) is, for example, 20% by mass relative to the total amount of the component (A). Preferably, the content is 25% by mass or more, and more preferably 30% by mass or more. When the content of the compound (A2) is 20% by mass or more, the low void property and strength of the cured product of the underfill material tend to be improved. The content of the compound (A2) is preferably, for example, 80% by mass or less, more preferably 75% by mass or less, and 70% by mass or less with respect to the total amount of the component (A). Further preferred.

  When using the compound (A3) as a compound having two or more ethylenically unsaturated double bonds in one molecule, the content of the compound (A3) is, for example, 10% by mass relative to the total amount of the component (A). Preferably, the content is 15% by mass or more, and more preferably 20% by mass or more. When the content of the compound (A3) is 10% by mass or more, the low void property and strength of the cured product of the underfill material tend to be improved. The content of the compound (A3) is, for example, preferably 80% by mass or less, more preferably 75% by mass or less, and 70% by mass or less with respect to the total amount of the component (A). Further preferred.

  The content of component (A) is, for example, preferably 5% by mass or more, more preferably 10% by mass or more, and further preferably 20% by mass or more with respect to the total amount of the underfill material. preferable. When the content of the component (A) is 5% by mass or more, the curability of the underfill material tends to be improved. The content of component (A) is, for example, preferably 90% by mass or less, more preferably 80% by mass or less, and further preferably 70% by mass or less, with respect to the total amount of the underfill material. preferable.

<(B) Reaction initiator>
The underfill material of the present embodiment contains (B) a reaction initiator (hereinafter also referred to as “component (B)”). A reaction initiator may be used individually by 1 type, and may be used in combination of 2 or more type.
The reaction initiator that can be used in the present embodiment is not particularly limited, and a commonly used reaction initiator can be used in an underfill material used for manufacturing an electronic component device. Here, the reaction initiator in the present embodiment means a compound capable of initiating a curing reaction of a compound having an ethylenically unsaturated double bond by a radical generated in energy application such as heat and light. Moreover, either the solid or liquid reaction initiator may be used at room temperature, or both may be used in combination so that the underfill material of the present embodiment becomes liquid at room temperature.

  Examples of the reaction initiator include organic peroxides, azo compounds, water-soluble catalysts, peroxides, and redox catalysts formed by combining a persulfate and a reducing agent. Among these, from the viewpoint of storage stability, the reaction initiator is preferably an 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, 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 peroxide and di-t-butyl peroxide; di (2-t-butylperoxyisopropyl) benzene, dicumyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxide Oxy) hexane, t- Dialkyl peroxides such as tilcumyl peroxide, di-t-hexyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne-3; dibenzoyl peroxide, di (4- Diacyl peroxides such as methylbenzoyl) peroxide; peroxydicarbonates such as di-n-propyl peroxydicarbonate and diisopropyl peroxydicarbonate; and 2,5-dimethyl-2,5-di (benzoylperoxy) Examples thereof include peroxyesters such as hexane, t-hexyl peroxybenzoate, and t-butyl peroxybenzoate.

  Examples of the azo compound include azobisisobutyronitrile, azobis-4-methoxy-2,4-dimethylvaleronitrile, azobiscyclohexanone-1-carbonitrile, and azodibenzoyl.

  Examples of the water-soluble catalyst include potassium persulfate and ammonium persulfate.

  The content of the component (B) is, for example, preferably 0.1% by mass to 20% by mass with respect to the total amount of the component (A), and from the viewpoint of curability, 0.5% by mass to 10% by mass. % Is more preferable. When the content of the component (B) is 0.1% by mass or more, the reaction proceeds sufficiently, and when it is 20% by mass or less, the storage stability of the underfill material tends to be improved.

<(C) Inorganic filler>
The underfill material of the present embodiment contains (C) an inorganic filler (hereinafter also referred to as “component (C)”). An inorganic filler may be used individually by 1 type, and may be used in combination of 2 or more type. When two or more inorganic fillers are used, for example, when two or more inorganic fillers having the same component and different average particle sizes are used, when two or more inorganic fillers having the same average particle size and different components are used, In addition, there may be mentioned a case where two or more inorganic fillers having different average particle diameters and types are used.

  The inorganic filler that can be used in the present embodiment is not particularly limited, and an inorganic filler that is generally used can be used in an underfill material that is used for manufacturing an electronic component device. Examples of inorganic fillers include silica such as spherical silica and crystalline silica, calcium carbonate, clay, alumina, silicon nitride, silicon carbide, boron nitride, calcium silicate, potassium titanate, aluminum nitride, beryllia, zirconia, zircon, fosterite, Examples thereof include powders such as steatite, spinel, mullite, and titania, beads formed by spheroidizing these, and glass fibers. Furthermore, aluminum hydroxide, magnesium hydroxide, zinc borate, zinc molybdate, etc. can be used as an inorganic filler having a flame retardant effect.

Among these, the material of the inorganic filler is preferably silica, and spherical silica is more preferable from the viewpoints of fluidity and penetration into the fine gaps. The method for producing the spherical silica is not particularly limited, and may be fused silica obtained by a melting method or deflagration silica obtained by a deflagration method. Further, these inorganic fillers may be those having a surface treated with a coupling agent as required.
In this specification, that the silica is spherical means that the sphericity satisfies the condition of 0.7 or more. As a method of measuring the sphericity, for example, image processing is performed with an electron microscope, and from the observed particle area and perimeter, (sphericity) = {4π × (area) ÷ (perimeter) ² } A method of calculating a value can be used.

  As coupling agents for treating the surface of inorganic fillers, known silane compounds such as epoxy silane, mercapto silane, amino silane, alkyl silane, ureido silane, vinyl silane, titanium compounds, aluminum chelate compounds, aluminum zirconium compounds, etc. Of coupling agents. Among these, it is preferable to use alkylsilane as a coupling agent.

  The volume average particle diameter of the inorganic filler is not particularly limited. The volume average particle diameter of the inorganic filler is, for example, preferably 0.1 μm to 10 μm, more preferably 0.15 μm to 7.5 μm, and still more preferably 0.20 μm to 5.0 μm. . If the volume average particle size of the inorganic filler is 10 μm or less, the permeability and fluidity of the underfill material into the fine gaps are improved, and the generation of voids and the unfilling of the underfill material tend not to occur. Furthermore, it is difficult for the inorganic filler to bite into the connection portion between the electronic component and the wiring board, and connection failure tends to occur. Moreover, if the volume average particle diameter of the inorganic filler is 0.1 μm or more, it tends to be difficult to increase the viscosity greatly.

  In the present specification, the “volume average particle diameter” of the inorganic filler means that the cumulative distribution is 50% in the cumulative distribution expressed by the accumulation of the frequencies, where the particle diameter is a class and the volume is a frequency using the following method. Mean particle diameter. As a method of measuring the particle size of the inorganic filler, for example, a method of measuring a large number of particles simultaneously using an apparatus such as laser diffraction, dynamic light scattering, and small-angle X-ray scattering, and an electron microscope and an atomic force microscope And the like, and measuring the particle diameter of each particle. Using a method such as liquid phase centrifugation, field flow fractionation, particle size exclusion chromatography, fluid dynamics chromatography or the like, a pretreatment for separating particles of 100 μm or more may be performed before measuring the particle size. Moreover, when a measurement sample is the hardened | cured material of an underfill material, the ash obtained as a residue after processing at high temperature of 800 degreeC or more with a muffle furnace etc. can be measured by said method.

  The maximum particle size of the inorganic filler is not particularly limited. For example, the maximum particle size of the inorganic filler is preferably 40 μm or less, more preferably 30 μm or less, and even more preferably 20 μm or less. When the maximum particle size of the inorganic filler is 40 μm or less, the permeability and fluidity of the underfill material into the fine gaps are improved, and voids and unfilling of the underfill material are less likely to occur. There is a tendency that the inorganic filler does not easily bite into the connection portion with the wiring board and connection failure is unlikely to occur.

  The minimum particle size of the inorganic filler is not particularly limited. The minimum particle diameter of the inorganic filler is, for example, preferably 0.075 μm or more, more preferably 0.080 μm or more, and further preferably 0.090 μm or more. If the minimum particle diameter of the inorganic filler is 0.075 μm or more, the underfill material tends to be difficult to thicken.

  The content of component (C) is not particularly limited. The content of component (C) is, for example, preferably 10% by mass or more, more preferably 20% by mass or more, and further preferably 30% by mass or more with respect to the total amount of the underfill material. preferable. When the content of the component (C) is 10% by mass or more, the strength of the cured product of the underfill material is further improved, and reliability such as temperature cycle resistance tends to be improved. The content of the component (C) is, for example, preferably 80% by mass or less, more preferably 75% by mass or less, and further preferably 70% by mass or less with respect to the total amount of the underfill material. preferable.

  As a measuring method of the content rate of a component (C), the method of calculating from the amount of ash obtained as a residue after processing the underfill material before hardening or after hardening at high temperature of 800 degreeC or more with a muffle furnace etc. is used, for example. be able to.

<(D) flexible agent>
The underfill material of this embodiment contains (D) a flexible agent (hereinafter also referred to as “component (D)”). A flexible agent may be used individually by 1 type, and may be used in combination of 2 or more type.
The flexible agent in the present embodiment is not particularly limited, and a commonly used flexible agent can be used in an underfill material used for manufacturing an electronic component device. Examples of the flexible agent include rubber particles such as styrene-butadiene rubber (SBR), nitrile-butadiene rubber (NBR), butadiene rubber (BR), urethane rubber (UR), and acrylic rubber (AR); polybutadiene, maleic acid Polybutadiene compounds liquefied at room temperature such as polybutadiene, epoxidized polybutadiene, hydrogenated polybutadiene; silicone rubber particles obtained by crosslinking linear polyorganosiloxanes such as polydimethylsiloxane, polymethylphenylsiloxane, polydiphenylsiloxane; and the like And core-shell polymer particles comprising a core of solid silicone particles obtained by emulsion polymerization or the like and a shell of an organic polymer such as an acrylic resin.

  The underfill material of this embodiment is a compound represented by (D1) the following general formula (I-7) or (I-8) as a flexible agent from the viewpoint of fillet shape and low voids (hereinafter referred to as “ It is preferable to contain the compound (also referred to as “compound (D1)”).

(In General Formula (I-7), R ⁷¹ and R ⁷² each independently represent a hydrogen atom or a methyl group, and R ⁷³ and R ⁷⁴ each independently have 1 carbon atom which may have a substituent. -18 represents a monovalent hydrocarbon group, p and q each independently represent a positive number, provided that R ⁷³ and R ⁷⁴ are different from each other, R ⁷³ and R ⁷⁴ are each independently It may be denatured.)

(In General Formula (I-8), R ⁸¹ , R ⁸² , and R ⁸³ each independently represent a hydrogen atom or a methyl group, and R ⁸⁴ , R ⁸⁵ , and R ⁸⁶ each independently have a substituent. represents a monovalent hydrocarbon group of good 1 to 18 carbon atoms have been, x, y, and z each independently represent a positive number. ^However, different from each other and ^{R 84} and ^{R 85, R 85} And R ⁸⁶ are different from each other, and R ⁸⁴ , R ⁸⁵ , and R ⁸⁶ may each independently be partially modified.)

In the general formula (I-7), the monovalent hydrocarbon group having 1 to 18 carbon atoms which may have a substituent represented by R ⁷³ is a monovalent aliphatic carbon group having 1 to 18 carbon atoms. It is preferably a hydrogen group, a monovalent alicyclic hydrocarbon group having 3 to 18 carbon atoms, or a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms.
The carbon number of the monovalent hydrocarbon group having 1 to 18 carbon atoms does not include the carbon number of the substituent.

The monovalent aliphatic hydrocarbon group having 1 to 18 carbon atoms represented by R ⁷³ is preferably a monovalent aliphatic hydrocarbon group having 1 to 14 carbon atoms, and monovalent having 1 to 10 carbon atoms. More preferably, it is an aliphatic hydrocarbon group.
Examples of the monovalent aliphatic hydrocarbon group having 1 to 18 carbon atoms include methyl group, ethyl group, propyl group, isopropyl group, butyl group, pentyl group, hexyl group, octyl group, decyl group, dodecyl group, and A vinyl group is mentioned. As the monovalent aliphatic hydrocarbon group having 1 to 18 carbon atoms, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, or a hexyl group is preferable, and a methyl group, an ethyl group, a propyl group, an isopropyl group, Or a butyl group is more preferable.

The monovalent alicyclic hydrocarbon group having 3 to 18 carbon atoms represented by R ⁷³ is preferably a monovalent alicyclic hydrocarbon group having 3 to 14 carbon atoms, and has 3 to 12 carbon atoms. It is more preferably a monovalent alicyclic hydrocarbon group.
Examples of the monovalent alicyclic hydrocarbon group having 3 to 18 carbon atoms include a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentyl group, and a cyclohexyl group.

The monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms represented by R ⁷³ is preferably a monovalent aromatic hydrocarbon group having 6 to 14 carbon atoms, and monovalent having 6 to 12 carbon atoms. The aromatic hydrocarbon group is more preferable.
Examples of the monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms include a phenyl group, a biphenyl group, and a terphenyl group.

Among these, R ⁷³ in formula (I-7) is more preferably a monovalent aliphatic hydrocarbon group having 1 to 18 carbon atoms which may have a substituent, and has a substituent. More preferably, it is a monovalent aliphatic hydrocarbon group having 1 to 12 carbon atoms.

Examples of the substituent that R ⁷³ in the general formula (I-7) may have include, for example, an alkyl group, an alkoxy group, an aryl group, an aryloxy group, a hydroxyl group, an amino group, a halogen atom, a methacryloyloxy group, and a mercapto group. , Imino group, ureido group, and isocyanate group. R ⁷³ preferably has no substituent.

In General Formula (I-7), the monovalent hydrocarbon group having 1 to 18 carbon atoms which may have a substituent represented by R ⁷⁴ is a monovalent aliphatic carbon group having 1 to 18 carbon atoms. It is preferably a hydrogen group, a monovalent alicyclic hydrocarbon group having 3 to 18 carbon atoms, or a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms. R ⁷⁴ in formula (I-7) has the same definition as R ⁷³ in formula (I-7), and the preferred range is also the same. However, R ⁷³ and R ⁷⁴ are different from each other.

  In general formula (I-7), p and q each independently represent a positive number. In addition, although p and q which are the number of structural units in a parenthesis show an integer value about a single molecule | numerator, they show the rational number which is an average value as an aggregate | assembly of a some kind of molecule | numerator.

As a compound represented by the general formula (I-7), R ⁷¹ and R ⁷² are each independently a hydrogen atom or a methyl group, and R ⁷³ and R ⁷⁴ are each independently a monovalent monovalent group having 1 to 18 carbon atoms. A compound which is an aliphatic hydrocarbon group and p and q are each independently a positive number is preferred.

Moreover, as a compound represented by general formula (I-7), ^R71 and ^R72 are respectively independently a hydrogen atom or a methyl group, ^R73 and ^R74 are each independently C1-C1 1 A compound having a valent aliphatic hydrocarbon group and p and q are each independently a positive number is more preferable.

Moreover, as a compound represented by general formula (I-7), ^R71 is a methyl group, ^R73 is a methyl group, Polymethylmethacrylate whose p is a positive number, and ^R72 is a hydrogen atom. Or it is a methyl group, R ⁷⁴ is a monovalent aliphatic hydrocarbon group having 1 to 6 carbon atoms, and q is a diblock copolymer with an alkyl poly (meth) acrylate having a positive number. Is more preferable.
For example, polymethyl methacrylate has a glass transition temperature of 100 ° C. to 120 ° C., and polybutyl acrylate has a glass transition temperature of −40 ° C. to 50 ° C. It is presumed that both of the characteristics of the material having excellent transparency and light resistance and the characteristics of polybutyl acrylate having excellent flexibility and adhesiveness can be obtained.

In the general formula (I-7), a plurality of R ⁷³ and R ⁷⁴ may be each independently partially modified. Examples of the modification include polar group modification and carboxy modification.

  The weight average molecular weight of the compound represented by the general formula (I-7) is preferably 5,000 to 1,000,000 from the viewpoints of heat shrinkability and adhesive force, and 10,000 to 700,000. It is more preferable that When the weight average molecular weight is 5,000 or more, curing shrinkage is reduced, toughness is increased, and the effect of improving connection reliability is increased. When the weight average molecular weight is 1,000,000 or less, an increase in viscosity is suppressed. However, it tends to be able to maintain low voids.

In addition, the weight average molecular weight in this specification is measured by a gel permeation chromatography (GPC) method, and is 3 using a standard polystyrene 5 sample set (PStQuick MP-H, PStQuick B (Tosoh Corporation, trade name). It is a value converted by a calibration curve approximated by the following equation: GPC conditions are shown below.
Pump: L-2130 (Hitachi High-Technologies Corporation, trade name)
Detector: L-2490 type RI (Hitachi High-Technologies Corporation, trade name)
Column oven: L-2350 (Hitachi High-Technologies Corporation, trade name)
Column: Gelpack GL-R440 + Gelpack GL-R450 + Gelpack GL-R400M (3 in total) (Hitachi Chemical Co., Ltd., trade 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

Examples of the compound represented by the general formula (I-7) available as a commercially available product include polymethyl methacrylate in which R ⁷¹ is a methyl group and R ⁷³ is a methyl group, and R ⁷² is a hydrogen atom. A diblock copolymer with polybutyl acrylate in which R ⁷⁴ is a butyl group (Kuraray Co., Ltd., trade name “Clarity LA1114”), and a diblock copolymer of polymethyl methacrylate and polybutyl acrylate. Examples thereof include compounds modified with polar groups (Arkema Co., Ltd., trade name “Nano Strength D51N”).

In General Formula (I-8), the monovalent hydrocarbon group having 1 to 18 carbon atoms which may have a substituent represented by R ⁸⁴ , R ⁸⁵ , and R ⁸⁶ is 1 to 18 carbon atoms. Are preferably monovalent aliphatic hydrocarbon groups, monovalent alicyclic hydrocarbon groups having 3 to 18 carbon atoms, or monovalent aromatic hydrocarbon groups having 6 to 18 carbon atoms. R ⁸⁴ , R ⁸⁵ , and R ⁸⁶ in general formula (I-8) have the same meaning as R ⁷³ in general formula (I-7), and the preferred range is also the same. However, R ⁸⁴ and R ⁸⁵ are different from each other, and R ⁸⁵ and R ⁸⁶ are different from each other.

  In general formula (I-8), x, y, and z each independently represent a positive number. In addition, although x, y, and z which are the number of structural units in a parenthesis show an integer value about a single molecule | numerator, it shows the rational number which is an average value as an aggregate | assembly of several types of molecule | numerators.

In the compound represented by the general formula (I-8), R ⁸¹ , R ⁸² , and R ⁸³ are each independently a hydrogen atom or a methyl group, and R ⁸⁴ , R ⁸⁵ , and R ⁸⁶ are each independently carbon. A compound having a monovalent aliphatic hydrocarbon group of 1 to 18 and wherein x, y, and z are each independently a positive number is preferable.

Moreover, as a compound represented by general formula (I-8), R ^<81> , R ^<82> and R ^<83> are respectively independently a hydrogen atom or a methyl group, R ^<84> , R ^<85> and R ^<86> are respectively independent. And a compound having a monovalent aliphatic hydrocarbon group having 1 to 6 carbon atoms, and x, y, and z are each independently a positive number.

Moreover, as a compound represented by general formula (I-8), ^R81 and ^R83 are methyl groups, ^R84 and ^R86 are methyl groups, and x and z are positive numbers. Trimethyl of methyl, poly (meth) acrylate with R ⁸² is a hydrogen atom or a methyl group, R ⁸⁵ is a monovalent aliphatic hydrocarbon group having 1 to 6 carbon atoms, and y is a positive number. More preferably, it is a block copolymer.

In General Formula (I-8), a plurality of R ⁸⁴ , R ⁸⁵ , and R ⁸⁶ may be independently modified partially. Examples of the modification include polar group modification and carboxy modification.

  The weight average molecular weight of the compound represented by the general formula (I-8) is preferably 5,000 to 1,000,000 from the viewpoints of heat shrinkability and adhesive force, and 10,000 to 700,000. It is more preferable that When the weight average molecular weight is 5,000 or more, curing shrinkage is reduced, toughness is increased, and the effect of improving connection reliability is increased. When the weight average molecular weight is 1,000,000 or less, an increase in viscosity is suppressed. However, it tends to be able to maintain low voids.

As a compound represented by the general formula (I-8) available as a commercial product, for example, polymethyl methacrylate in which R ⁸¹ and R ⁸³ are methyl groups, and R ⁸⁴ and R ⁸⁶ are methyl groups, A triblock copolymer with polybutyl acrylate in which R ⁸² is a hydrogen atom and R ⁸⁵ is a butyl group (Arkema Co., Ltd., trade names “Nano Strength M22”, “Nano Strength M51”, “Nano Strength M52” , “Nano Strength M53”, “Nano Strength M75”, “Nano Strength M85”, “Nano Strength SM5590”, “Nano Strength SM6290” (Kuraray Co., Ltd., trade names “Clarity LA2140”, “Clarity LA2250”, “Clarity” LA2330 "," Clarity LA4285 "), A compound obtained by modifying a triblock copolymer of methyl methacrylate and polybutyl acrylate with a polar group (Arkema Co., Ltd., trade names “Nano Strength M22N”, “Nano Strength M52N”), and polymethyl methacrylate and polyacryl Examples include compounds obtained by carboxyl-modifying a triblock copolymer with butyl acid (Arkema Co., Ltd., trade names “Nanostrength SM4032XM10”, “Nanostrength M75M”, “Nanostrength M85M”).

  When using the compound (D1) as the flexible agent, the content of the compound (D1) is, for example, preferably 50% by mass or more and 75% by mass or more with respect to the total amount of the flexible agent. More preferred. When the content of the compound (D1) is 50% by mass or more, it tends to be excellent in fillet shape and low void properties. The content of the compound (D1) is, for example, preferably 1% by mass or more, more preferably 1% by mass to 20% by mass, and more preferably 1% by mass to the total amount of the underfill material. More preferably, it is 10 mass%.

  The content of component (D) is, for example, preferably 1% by mass to 30% by mass and more preferably 2% by mass to 20% by mass with respect to the total amount of the underfill material. When the content of the component (D) is 1% by mass or more, the effect of reducing the curing shrinkage and thermal expansion / contraction of the cured product of the underfill material tends to be improved, and the content of the component (D) is 30% by mass or less. When it is, there exists a tendency for the viscosity of an underfill material to be maintained and for a moldability to be maintained.

<Various additives>
The underfill material of this embodiment is necessary in addition to (A) a compound having an ethylenically unsaturated double bond, (B) a reaction initiator, (C) an inorganic filler, and (D) a flexible agent. Depending on the case, various additives may be further contained.

  Examples of the additive include various additives such as a coupling agent, a flux agent, a thixotropic agent, a surfactant, and an ion trap agent. The underfill material of the present embodiment is not limited to the following additives, and may contain various additives well known in the art as needed.

(Coupling agent)
The underfill material of this embodiment may contain a coupling agent as necessary from the viewpoint of improving the wettability of the resin component and the inorganic filler. The coupling agent that can be used in the present embodiment is not particularly limited as long as the effects of the present invention are achieved.

  As the coupling agent, for example, at least one silane compound selected from silane compounds having a primary amino group, a secondary amino group, or a tertiary amino group, epoxy silane, mercapto silane, alkyl silane, ureido silane, Examples include various silane compounds such as vinyl silane, titanium compounds, aluminum chelate compounds, and aluminum-zirconium compounds.

  The underfill material of this embodiment may contain a coupling agent individually by 1 type, and may contain it in combination of 2 or more types.

  When the underfill material of this embodiment contains a coupling agent, it is preferable that the content rate of a coupling agent is 0.05 mass%-5 mass% with respect to the whole quantity of an inorganic filler, More preferably, it is 0.1 mass%-2.5 mass%. If the coupling agent content is 0.05% by mass or more, the adhesiveness between the cured underfill material and the wiring board or electronic component tends to be improved, and the coupling agent content is 5% by mass or less. If this is the case, the moldability is improved and the generation of voids tends to be reduced.

(Flux agent)
The underfill material of the present embodiment may contain a flux agent as necessary to impart a flux function.
As a flux agent, the hydrohalic acid amine salt conventionally used in this technical field is mentioned, for example. Other preferable fluxing agents include, from the viewpoint of electrical characteristics, for example, compounds having a phenolic hydroxyl group and a carboxy group such as hydroxybenzoic acid, acid anhydrides having a carboxy group such as trimellitic acid, abietic acid, and adipic acid. , Organic acids such as ascorbic acid, citric acid, 2-furancarboxylic acid and malic acid, and compounds having two or more alcoholic hydroxyl groups per molecule.

  The underfill material of this embodiment may contain a flux agent alone or in combination of two or more.

  When the underfill material of this embodiment contains a flux agent, the content rate of the flux agent is not particularly limited as long as the flux function is manifested. The content of the flux agent is, for example, preferably 0.1% by mass to 10% by mass, and more preferably 0.5% by mass to 5% by mass with respect to the total amount of the underfill material. If the content of the fluxing agent is 0.1% by mass or more, the wettability between the underfill material and the connection portion in the wiring board and the electronic component is increased, and the connectivity with the wiring board and the electronic component tends to be improved. If the content rate of a flux agent is 10 mass% or less, generation | occurrence | production of a void will be reduced and it exists in the tendency for reliability, such as migration resistance, to improve.

(Thixotropic agent)
The underfill material of the present embodiment may contain a thixotropic agent as necessary from the viewpoint of improving shape retention. Examples of the thixotropic agent include a hydrogenated castor oil compound obtained by adding hydrogen to castor oil, an oxidized polyethylene compound obtained by oxidizing polyethylene and introducing a polar group, a vegetable oil fatty acid and an amine. Amide wax compounds, salts of long-chain polyaminoamides and acid polymers, unsaturated polycarboxylic acid polymers, finely divided silica, and crushed silica.

  When the underfill material contains a thixotropic agent, entrainment of voids can be suppressed. That is, when an underfill material is supplied to a wiring board or an electronic component, if the underfill material flows without being able to retain its shape, it tends to entrain voids, but contains a thixotropic agent. As a result, the underfill material is less likely to flow and void entrainment tends to be suppressed.

  Among thixotropic agents, silica particles such as a salt of a long-chain polyaminoamide and an acid polymer, an unsaturated polycarboxylic acid polymer, finely divided silica, and crushed silica are included from the viewpoints of handleability, moldability, and low voids. Preferably, fine powder silica is more preferable from the viewpoint of shape retention.

  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” (Bic Chemie Japan Co., Ltd., trade name) is available as a commercial product.

  The average particle size of the fine powder silica is preferably 5 nm to 200 nm, and more preferably 5 nm to 50 nm.

As fine powder silica, silica particles whose surface is treated with silicone oil or a coupling agent may be used.
As a coupling agent for treating the surface of silica particles, known silane compounds such as epoxy silane, mercapto silane, amino silane, alkyl silane, ureido silane, vinyl silane, titanium compound, aluminum chelate compound, aluminum zirconium compound, etc. A coupling agent is mentioned. Among these, it is preferable to use alkylsilane as a coupling agent.

  Examples of fine powder silica whose surface is treated with silicone oil or a coupling agent include, for example, “R974” (Nippon Aerosil Co., Ltd., trade name) having an average particle diameter of 12 nm and surface-treated with dimethylsilane. "RX200" (Nippon Aerosil Co., Ltd., trade name) surface-treated with trimethylsilane, and "RY200" (Nippon Aerosil Co., Ltd., product) having an average particle size of 12 nm and surface-treated with dimethylsiloxane Name), “R202” (Nippon Aerosil Co., Ltd., trade name) surface-treated with dimethylsiloxane having an average particle size of 14 nm, “RA200H” (Japan) having an average particle size of 12 nm and surface-treated with aminosilane (Japan) Aerosil Co., Ltd., trade name), average particle size is 12 nm, alkylsila "R805" (Nippon Aerosil Co., Ltd., trade name), surface-treated with "R7200" (Nippon Aerosil Co., Ltd., trade name) having an average particle diameter of 12 nm and surface-treated with methacryloxysilane, and average particles “YA050C-SP3” (Admatechs Co., Ltd., trade name) having a diameter of 50 nm and surface-treated with phenylsilane is commercially available.

  The average particle diameter of the crushed silica is preferably 10 μm or less, more preferably 7.5 μm or less, and even more preferably 5 μm or less. Further, crushed silica whose surface is treated with silicone oil or a coupling agent may be used. As the crushed silica, for example, “MC3000” (Admatechs Co., Ltd., trade name) is commercially available.

  In this specification, the “average particle size” of finely divided silica and crushed silica is imaged using an electron microscope or the like, and the particle size of each particle is measured, and the particle size obtained by the arithmetic average thereof is calculated. means. As a method for measuring the particle diameter of finely divided silica and crushed silica, for example, a method of measuring the particle diameter of each particle by imaging using a transmission electron microscope, a scanning electron microscope, an atomic force microscope, etc. Etc. Using a method such as liquid phase centrifugation, field flow fractionation, particle size exclusion chromatography, fluid dynamics chromatography or the like, a pretreatment for separating particles of 100 μm or more may be performed before measuring the particle size. Moreover, when a measurement sample is the hardened | cured material of an underfill material, the ash obtained as a residue after processing at high temperature of 800 degreeC or more with a muffle furnace etc. can be measured by said method.

  The underfill material of the present embodiment may contain a thixotropic agent alone or in combination of two or more.

  When the underfill material of this embodiment contains a thixotropic agent, the content of the thixotropic agent may be, for example, 0.1% by mass to 20% by mass with respect to the total amount of the underfill material. Preferably, it is 0.5 mass%-10 mass%. If the content of the thixotropic agent is 0.1% by mass or more, the expected effect expected for the content of the thixotropic agent is easily exhibited, and the content of the thixotropic agent is 20% by mass or less. If it exists, the viscosity fluctuation | variation of an underfill material will be suppressed and it exists in the tendency for a moldability to improve more.

(Surfactant)
The underfill material of this embodiment may contain a surfactant as necessary from the viewpoint of improving fillet properties.
The surfactant that can be used in the present embodiment is not particularly limited. For example, a nonionic surfactant that is generally used in an underfill material used for manufacturing an electronic component device may be used. it can. Examples of the surfactant include a polyoxyethylene alkyl ether surfactant, a polyoxyalkylene alkyl ether surfactant, a sorbitan fatty acid ester surfactant, a polyoxyethylene sorbitan fatty acid ester surfactant, and a polyoxyethylene sorbitol fatty acid ester interface. Activator, glycerin fatty acid ester surfactant, polyoxyethylene fatty acid ester surfactant, polyoxyethylene alkylamine surfactant, alkyl alkanolamide surfactant, polyether modified silicone surfactant, aralkyl modified silicone surfactant, Examples include polyester-modified silicone surfactants and polyacrylic surfactants. Among these, polyether-modified silicone surfactants and aralkyl-modified silicone surfactants tend to be effective in reducing the surface tension of the underfill material.
As these surfactants, “BYK-307”, “BYK-333”, “BYK-377”, “BYK-323” (BIC Chemie Japan Co., Ltd., trade name) and the like are available as commercial products. .

  The underfill material of this embodiment may contain a surfactant alone or in combination of two or more.

  When the underfill material of this embodiment contains a surfactant, the content of the surfactant is, for example, 0.001% by mass to 0.1% by mass with respect to the total amount of the underfill material. Preferably, it is 0.005 mass%-0.075 mass%. If the content of the surfactant is 0.001% by mass or more, the fillet property tends to be improved.

(Ion trap agent)
The underfill material of the present embodiment may contain an ion trap agent as necessary from the viewpoint of improving moisture resistance and high temperature storage characteristics.

  The ion trapping agent that can be used in the present embodiment is not particularly limited as long as it is a commonly used ion trapping agent in an underfill material used for manufacturing an electronic component device. As an ion trap agent, the compound represented by the following general formula (II-1) or (II-2) is mentioned, for example.

Mg _1-a Al _a (OH) ₂ (CO ₃ ) _{a / 2} · uH ₂ O (II-1)
(In general formula (II-1), a is 0 <a ≦ 0.5, and u is a positive number.)
BiO _b (OH) _c (NO ₃ ) _d (II-2)
(In general formula (II-2), b is 0.9 ≦ b ≦ 1.1, c is 0.6 ≦ c ≦ 0.8, and d is 0.2 ≦ d ≦ 0.4.)

  The ion trap agent is available as a commercial product. For example, as the compound represented by the general formula (II-1), for example, “DHT-4A” (Kyowa Chemical Industry Co., Ltd., trade name) is commercially available. Moreover, as a compound represented by general formula (II-2), "IXE500" (Toagosei Co., Ltd., brand name) is available as a commercial item, for example.

Examples of ion trapping agents other than the above include hydrous oxides of elements selected from magnesium, aluminum, titanium, zirconium, antimony, and the like.
An ion trap agent may be used individually by 1 type, or may be used in combination of 2 or more type.
The underfill material of the present embodiment may contain an ion trapping agent alone or in combination of two or more.

When the underfill material of this embodiment contains an ion trap agent, the content rate of an ion trap agent is 0.1 mass%-5.0 mass% with respect to the whole quantity of a component (A), for example. Is preferable, and it is more preferable that it is 1.0 mass%-3.0 mass%. The average particle diameter of the ion trapping agent is preferably 0.1 μm to 3.0 μm, and the maximum particle diameter is preferably 10 μm or less.
In addition, the average particle diameter and maximum particle diameter of the ion trapping agent are measured using the same method as that for the inorganic filler.

  In the underfill material of the present embodiment, as other additives, colorants such as dyes and carbon black, flame retardants, diluents and the like can be used as necessary.

<Manufacturing method of underfill material>
The underfill material of this embodiment can be prepared by any method as long as the various components can be dispersed and mixed. As a general method, the underfill material of the present embodiment can be obtained by weighing the components, mixing and kneading using a roughing machine, mixing roll, planetary mixer, etc., and defoaming as necessary. it can.

[Method of manufacturing electronic component device]
The electronic component device manufacturing method of the present embodiment (hereinafter also referred to as “the manufacturing method of the present embodiment” as appropriate) includes a surface of the electronic component facing the wiring substrate and a surface of the wiring substrate facing the electronic component. A supply step of supplying the underfill material of the present embodiment to at least one surface selected from the group consisting of: and after the supply step, the electronic component and the wiring board are connected via a connection portion; and A connection step of curing the fill material.

  The manufacturing method according to the present embodiment includes the underfill material according to the present embodiment on at least one surface selected from the group consisting of a surface facing the wiring board in the electronic component and a surface facing the electronic component in the wiring board. This is a manufacturing method to which a pre-feed method is applied in which the connection through the connecting portion between the electronic component and the wiring board and the curing of the underfill material are performed after supplying the substrate. The connection between the electronic component and the wiring board and the curing of the underfill material may be performed collectively or separately. From the viewpoint of simplifying the manufacturing process, it is preferable to collectively connect the electronic component and the wiring board and cure the underfill material.

  The manufacturing method of this embodiment is a manufacturing method of an electronic component device to which a pre-feed method is applied. By using the underfill material of this embodiment having a predetermined composition in the supply process, the curing time of the underfill material can be reduced. Since it can be shortened, the generation of voids is small, and the adhesiveness with the electronic component is excellent, an electronic component device with excellent electrical connection reliability can be manufactured. The present inventors consider the reason as follows.

  That is, according to the knowledge obtained by the present inventors, the underfill material includes an (A) compound having an ethylenically unsaturated double bond, whereby the underfill in the electronic component device manufacturing method to which the pre-feed method is applied. The curing time of the fill material is shortened, and the generation of voids tends to be suppressed.

On the other hand, when a compound having an ethylenically unsaturated double bond is used, the underfill material tends to be inferior in adhesiveness with an electronic component. If the underfill material tends to be inferior in adhesion to the electronic component, there is a tendency that peeling occurs between the underfill material and the electronic component when reflow processing is performed in the manufacturing process of the electronic component device. The electrical connection between the electronic component and the wiring board is impaired due to the peeled portion, and it becomes difficult to manufacture an electronic component device having excellent electrical connection reliability.
In this embodiment, the underfill material contains (A) an addition reaction product of (A1) epoxy resin and (meth) acrylic acid as a compound having an ethylenically unsaturated double bond, and (D) is acceptable. Contains a glaze. With this configuration, in this embodiment, shortening of the curing time of the underfill material, suppression of void generation, and high adhesiveness with the electronic component are achieved. This is because the underfill material contains (A1) an addition reaction product of an epoxy resin and (meth) acrylic acid and (D) a flexible agent, thereby improving the adhesiveness of the cured product of the underfill material. The present inventors consider that.

  Hereinafter, each process which the manufacturing method of this embodiment has is demonstrated.

<Supply process>
The supplying step in the manufacturing method of the present embodiment supplies the underfill material to at least one surface selected from the group consisting of a surface facing the wiring board in the electronic component and a surface facing the electronic component in the wiring substrate. It is a process.

As an underfill material in a supply process, it contains (A) a compound having an ethylenically unsaturated double bond, (B) a reaction initiator, (C) an inorganic filler, and (D) a flexible agent. An underfill material in which the compound having an ethylenically unsaturated double bond contains an addition reaction product of (A1) an epoxy resin and (meth) acrylic acid is used.
The underfill material used in the supply process is the underfill material of the present embodiment, and details thereof are as described above.

  The wiring board is formed by forming a conductor wiring including a connection electrode on a base material. The kind of base material which comprises a wiring board is not restrict | limited in particular, The organic substrate containing fiber base materials, such as FR-4 (Flame Retardant-4) and FR-5 (Flame Retardant-5), and a fiber base material are not included. Examples include build-up type organic substrates, organic films such as polyimide and polyester, and substrates including inorganic materials such as alumina, glass, and silicon. The inorganic material includes a semiconductor chip such as silicon. The kind of conductor wiring is not specifically limited, The conductor wiring applicable to the wiring board in an electronic component can be used. The conductor wiring in the wiring board may be formed by a method such as a semi-additive method or a subtractive method.

  The electronic component is not particularly limited, and a semiconductor chip itself not packaged with a resin or the like, a semiconductor package called a CSP (Chip Scale Package), a BGA (Ball Grid Array), or the like can be used.

The wiring board is connected to the electronic component through the connection portion in a connection process described later.
The material of the connection part is not particularly limited, and can be selected from materials usually used for solder or the like. From the viewpoint of environmental problems, Cu solder, Au solder, lead-free solder or the like may be used. The bump may be formed on the electronic component side or on the substrate side. For connection between the bump and the circuit electrode, solder such as Ag—Cu solder, Sn—Cu solder, Sn—Bi solder may be used.

  A method for supplying the underfill material to the wiring board or the electronic component is not particularly limited. As a method for supplying the underfill material to the wiring board or the electronic component, for example, a method using a dispenser such as an air dispenser, a jet dispenser, a screw type dispenser, an auger type dispenser, a method using casting, and printing such as screen printing. The method using is mentioned. From the viewpoint of reducing void entrainment when supplying the underfill material, a method using a dispenser is preferable.

  The aspect at the time of supplying an underfill material to a wiring board or an electronic component is not particularly limited. When supplying the underfill material on the wiring board, for example, an aspect in which the entire electronic component mounting position is supplied, and a cross shape including two lines along a diagonal line corresponding to the electronic component mounting position. A mode in which one cross shape is further shifted by 45 ° to another cross shape and a mode in which the cross shape is supplied and a mode in which the electronic component is mounted at the center of the mounting position are exemplified. In order to suppress creeping of the underfill material from the viewpoint of reliability, it is preferable to supply a cross shape or a shape in which another cross shape is further shifted by 45 ° and overlapped. When the substrate electrode is provided on the wiring board, it is preferable to supply the underfill material to the mounting position of the electronic component including the portion where the substrate electrode is provided.

  The temperature at which the underfill material is supplied onto the wiring board or electronic component can be selected according to the properties of the underfill material. The temperature of the underfill material and the substrate surface is preferably 25 ° C. to 150 ° C., respectively, and more preferably 25 ° C. to 100 ° C. from the viewpoint of ejection stability.

  The needle diameter of the dispenser is not particularly limited, and is preferably selected in consideration of the degree of bubble entrainment and discharge stability when the underfill material is supplied. Specifically, in the case of discharging the underfill material in the manufacturing method of the present embodiment, it is preferable to use a needle having a diameter of 0.1 mm to 1.0 mm, and a needle having a diameter of 0.2 mm to 0.5 mm. It is more preferable to use

<Connection process>
The connecting step in the manufacturing method of the present embodiment is a step of connecting the electronic component and the wiring board through the connecting portion after the supplying step, and curing the underfill material of the present embodiment.

More specifically, the connecting step in the manufacturing method of the present embodiment is performed in the gap between the electronic component and the wiring board by pressurizing the electronic component and the wiring board while facing each other through the connecting portion. A pressurizing process in which the underfill material is filled and the electronic component and the wiring board are brought into contact with each other through the connection portion, and heat treatment is performed in a state where the electronic component and the wiring board are in contact with each other through the connection portion In addition, it is preferable to include a heat treatment step of connecting the electronic component and the wiring board via the connection portion and curing the underfill material of the present embodiment.
In addition to the pressurizing step and the heat treatment step, the connecting step may include other steps such as an exposure step, a step of applying an impact by ultrasonic waves, microwaves, radio waves, and the like.
Hereinafter, the connection process will be described in detail by taking as an example an aspect including a pressurizing process and a heat treatment process.

<< Pressurization process >>
In the pressurizing step, the electronic component and the wiring board are pressed in a state of being opposed to each other through the connection portion, the gap between the electronic component and the wiring board is filled with the underfill material of the present embodiment, and the electronic In this step, the component and the wiring board are brought into contact with each other through the connection portion.

  In the pressurizing step, pressure is applied in a state where the electronic component and the wiring board are opposed to each other via the connecting portion, and the electronic component and the wiring substrate are brought into contact via the connecting portion. This method is not particularly limited. As an example of a method for bringing an electronic component and a wiring board into contact with each other through a connecting portion, a method using a flip chip bonder can be cited.

  Heating may be performed in the pressurizing step. In the pressurizing step, pressurization and heating may be performed simultaneously, either pressurization or heating may be started first, or either pressurization or heating is ended first. May be.

  The temperature of the underfill material in the pressurizing step (hereinafter also referred to as “filling temperature” as appropriate) is particularly a temperature that can maintain a viscosity sufficient to fill the gap between the electronic component and the wiring board with the underfill material. It is not limited. The filling temperature is, for example, 25 ° C to 150 ° C, preferably 40 ° C to 125 ° C, and more preferably 50 ° C to 100 ° C. When the filling temperature of the underfill material is 25 ° C. or higher, the fluidity of the underfill material tends to be sufficiently obtained. When the filling temperature of the underfill material is 150 ° C. or less, an increase in viscosity accompanying the progress of the curing reaction of the underfill material is suppressed, and sufficient fluidity tends to be secured. The filling temperature of the underfill material in the pressurizing step may be constant or may be changed as long as good fluidity of the underfill material is obtained.

  In the pressurizing step, the underfill material may be thickened at a viscosity at which the underfill material can maintain a liquid state. Here, the underfill material being liquid means that the viscosity of the underfill material is 1000 Pa · s or less. The method for measuring the viscosity of the underfill material is as described above.

  In the pressing process, the magnitude of the pressure applied to the electronic component and the wiring board is the same as in the general flip chip mounting process. It can be set in consideration of the amount of deformation of the wiring on the wiring board to be received. Specifically, for example, it is preferable to set so that the load received by one connection portion is about 0.01 g to 100 g.

<< Heat treatment process >>
In the heat treatment step, the electronic component and the wiring board are heat-treated in contact with each other through the connecting portion, the electronic component and the wiring substrate are connected through the connecting portion, and the underfill material of the present embodiment Is a step of curing.

  The method for heat treatment is not particularly limited. Examples of the heat treatment method include a method of heating a contact portion between a flip chip bonder and a wiring board or an electronic component, and a method using a reflow furnace. From the viewpoint of hardly causing displacement of the electronic component, a method of heating the contact portion between the flip chip bonder and the wiring board or the electronic component is preferable as the heat treatment method.

  The heat treatment step is performed at a temperature that is equal to or higher than the melting point of the material constituting the connection part and that the underfill material can be thermoset from the viewpoint of securing the connection through the connection part between the electronic component and the wiring board. Is preferred. That is, it is preferable that the connection is formed between the wiring on the wiring board and the electronic component, and the underfill material is cured at a temperature at which the connection can be reinforced.

  The heat treatment (heating) temperature is, for example, preferably 150 ° C to 300 ° C, more preferably 200 ° C to 280 ° C, and further preferably 220 ° C to 260 ° C. By this heat treatment, the underfill material is cured.

  The heat treatment is preferably performed in a short time from the viewpoint of improving productivity. Specifically, the heating rate in the heat treatment step is preferably 10 ° C./second or more, more preferably 20 ° C./second or more, and further preferably 30 ° C./second or more. The upper limit of the heating rate is not particularly limited, but may generally be 200 ° C./second or less.

  The heat treatment time varies depending on the material constituting the connection part and the type of component contained in the underfill material, the connection part is formed between the wiring on the wiring board and the electronic component, and the underfill material is heated. There is no particular limitation as long as it is time for curing and reinforcement of the connection part.

  From the viewpoint of improving productivity, the heat treatment time is preferably as short as possible. When the connecting portion is solder, the heat treatment time is preferably 60 seconds or shorter, more preferably 45 seconds or shorter, and even more preferably 30 seconds or shorter. In the case of copper-copper or copper-gold metal connection, the heat treatment time is preferably 30 seconds or less. The lower limit of the heat treatment time is not particularly limited, but may generally be 0.1 seconds or longer.

  In the heat treatment step, the gelation time at 200 ° C. of the underfill material is preferably 5.0 seconds or less from the viewpoint of suppressing generation of voids in the cured product of the underfill material. The lower limit of the gelation time at 200 ° C. is not particularly limited, but may generally be 1 second or longer.

  The gelation time at 200 ° C. of the underfill material is measured according to JIS K 6910 (2007) or ISO 10082 (1999). Specifically, 0.5 g of an underfill material is dropped on a hot plate at 200 ° C., and stirred so as not to spread too much with a spatula. After dropping, the viscosity of the underfill material increases, and the time until the underfill material is cut without stringing when the spatula is lifted up is defined as the gel time.

  In the heat treatment step, after performing the above heat treatment, if necessary, the underfill material is sufficiently cured, and the heat treatment is further performed in the range of 100 ° C. to 200 ° C. for 0.1 hour to 10 hours. (Post-heating treatment) may be performed.

<< Exposure process >>
The connection process may include an exposure process as a process other than the pressurization process and the heat treatment process in order to make the underfill material harder as necessary. The exposure step may be performed together with the heat treatment in the heat treatment step, or may be performed as a separate step after the heat treatment step is completed.

  When performing the exposure process in the exposure process together with the heat treatment in the heat treatment process, the heat treatment and the exposure process may start and end of these processes at the same time, or one of the processes may be started first. One process may be terminated later.

  The exposure process in an exposure process will not be restrict | limited especially if it can process an underfill material by exposure. Various exposure conditions such as a light source, an exposure wavelength, and an exposure time applied to the exposure process and an exposure apparatus can be appropriately selected according to the components contained in the underfill material.

<< Example of Embodiment of Manufacturing Method >>
Hereinafter, an example of the manufacturing method of the present embodiment will be described with reference to the drawings. The size of the members in the drawings is conceptual, and the relative relationship between the sizes of the members is not limited to this.
In addition, embodiment shown below is an example of the aspect which supplies the underfill material of this embodiment to the surface of the side facing the electronic component of a wiring board. Further, the bump is provided on the electronic component side, and the electronic component and the wiring board are connected via the bump. However, the present invention is not limited to this embodiment.

FIG. 1 is a process explanatory diagram of a method of manufacturing an electronic component device according to a first supply method.
In the present embodiment, as shown in FIG. 1, a semiconductor chip (electronic component) 1 including a solder bump (connection part) 2, a wiring substrate 5 including a connection pad 3 and a solder resist 4, and an underfill material 6 are used. Yes.

  First, as shown in FIG. 1A, the underfill material 6 is supplied to the surface of the wiring board 5 on which the connection pads 3 are provided (the side facing the semiconductor chip 1 of the wiring board 5) (supply). Process). Next, as shown in FIG. 1B, the semiconductor chip 1 and the wiring substrate 5 are opposed to each other through the solder bumps 2 and pressed, whereby the underfill material 6 is placed in the gap between the semiconductor chip 1 and the wiring substrate 5. In addition, the semiconductor chip 1 and the connection pads 3 of the wiring substrate 5 are brought into contact with each other through the solder bumps 2 (pressure process).

Next, heat treatment is performed in a state where the semiconductor chip 1 and the connection pads 3 of the wiring board 5 are pressed and in contact with each other via the solder bumps 2, so that the semiconductor chips 1 and the connection pads 3 of the wiring board 5 are solder bumps. 2 and the underfill material 6 is cured (heat treatment step).
Through the above steps, the electronic component device according to the present embodiment is manufactured.

[Electronic component equipment]
The electronic component device of the present embodiment is disposed between an electronic component, a wiring board that is disposed so as to face the electronic component, and is connected to the electronic component via a connecting portion, and the electronic component and the wiring board. And a cured product of the underfill material of the present embodiment. The electronic component device of the present embodiment can be manufactured by the manufacturing method of the electronic component device of the present embodiment.

  Electronic component devices include lead frames, wired tape carriers, rigid and flexible wiring boards, glass, silicon wafers and other support members (wiring boards), active elements such as semiconductor chips, transistors, diodes, thyristors, capacitors, An electronic component device or the like obtained by mounting electronic components such as passive elements such as resistors, resistor arrays, coils, switches, etc., and sealing necessary portions with the underfill material of this embodiment can be used.

The electronic component device is particularly a semiconductor device in which a semiconductor element is flip-chip bonded by bump connection to a rigid and flexible wiring board and wiring formed on glass. Specific examples include semiconductor devices such as flip chip BGA (Ball Grid Array), LGA (Land Grid Array), and COF (Chip On Film), and the underfill material of this embodiment has excellent reliability. It is suitable as an underfill material for flip chip.
The underfill material of this embodiment can shorten the curing time and can reduce the generation of voids. Therefore, the underfill material can be suitably used for flip chip bonding applications where the pitch width of the bumps is narrow. The underfill material of the present embodiment is particularly suitable for bump connection with a bump pitch width of 10 μm to 200 μm, for example.

  The field of flip chip in which the underfill material of the present embodiment is particularly suitable is a flip chip semiconductor element using lead-free solder such as Sn-Ag-Cu solder as a bump material for connecting a wiring board and a semiconductor element. In addition, good reliability can be maintained even for a flip chip having a lead-free solder bump connection that is brittle in physical properties as compared with conventional lead solder.

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

[Examples 1 to 12, Comparative Examples 1 to 11]
<Addition reaction product of (A1) epoxy resin and (meth) acrylic acid>
Addition reaction product of bisphenol A diglycidyl ether and acrylic acid (Kyoeisha Chemical Co., Ltd., trade name “Epoxy ester 3000A”)
・ Addition reaction product of diglycidyl ether and acrylic acid obtained by adding 2 mol of propylene oxide to bisphenol A (Kyoeisha Chemical Co., Ltd., trade name “epoxy ester 3002A (N)”)
・ Epoxy acrylate compound (Daicel Ornex Co., Ltd., trade name “EBECRYL 3708”)

<(A2) Tricyclodecane dimethylol di (meth) acrylate>
・ Tricyclodecane dimethylol diacrylate (Shin Nakamura Chemical Co., Ltd., trade name “A-DCP”)
<(A3) (Meth) acrylate compound represented by general formula (I-2)>
・ Bisphenol A type ethylene oxide-modified diacrylate (Shin Nakamura Chemical Co., Ltd., trade name “ABE-300”)
・ Bisphenol A type ethylene oxide modified diacrylate (Hitachi Chemical Co., Ltd., trade name “FA-321A”)

<(A) Other compounds having an ethylenically unsaturated double bond>
2-acryloyloxyethyl-2-hydroxyethyl-phthalic acid (Kyoeisha Chemical Co., Ltd., trade name “HOA-MPE (N)”)
・ EO, PO modified urethane dimethacrylate (Shin Nakamura Chemical Co., Ltd., trade name “UA-13”)

<(B) Reaction initiator>
・ Dicumyl peroxide (Kayaku Akzo Co., Ltd., trade name “Perkadox BC-FF”)

<(C) Inorganic filler>
-Spherical silica particles having a volume average particle size of 0.5 μm, a maximum particle size of 5 μm, and a surface treated with a coupling agent (Admatex Co., Ltd., trade names “SE-2050-SMJ”, “SE-2050-SEJ”)

<(D) flexible agent>
A compound obtained by modifying a diblock copolymer of polymethyl methacrylate and polybutyl acrylate with a polar group (Arkema Co., Ltd., trade name “Nanostrength D51N”, weight average molecular weight: 35,000)
: Triblock copolymer of polymethyl methacrylate and polybutyl acrylate (Kuraray Co., Ltd., trade name “Clarity LA2250”, weight average molecular weight: 52,000)
: Maleic acid-modified polybutadiene (Sakai Industrial Co., Ltd., trade name “RICON 130MA8”)

<Other resins, curing agents, etc.>
(Epoxy resin)
-Epoxy equivalent 160g / eq bisphenol F type epoxy resin (Nippon Steel Sumikin Chemical Co., Ltd., trade name "YDF-8170C")
(Epoxy curing agent)
A cyclic acid anhydride having an acid anhydride equivalent of 234 g / eq (Mitsubishi Chemical Corporation, trade name “YH-306”)
(Curing catalyst)
・ 2-Ethyl-4-methylimidazole

<Other various additives>
(Coupling agent)
・ Methacryloyloxypropyltrimethoxysilane ・ γ-glycidoxypropyltrimethoxysilane (thixotropic agent)
・ Powdered silica with a volume average particle diameter of 12 nm (Nippon Aerosil Co., Ltd., trade name “R-805”)

  The above components were blended in parts by mass shown in Tables 1 and 2 and kneaded and dispersed with a three-roller and a raking machine, and then vacuum degassed to produce the underfill materials of Examples and Comparative Examples. . “(C) Amount of inorganic filler” and “(D) Amount of flexible agent” shown in Table 1 are contents (% by mass) relative to the total mass of the underfill material.

  Each underfill material obtained in Examples and Comparative Examples was evaluated by the following tests. The evaluation results are shown in Tables 3 to 4.

(1) Gelation time 0.5 g of underfill material was dropped on a hot plate at 200 ° C., and stirred so as not to spread too much with a spatula. After dropping, the viscosity of the underfill material increased, and the time until the underfill material was cut without stringing when the spatula was lifted up was defined as the gel time (seconds).

(2) Viscosity The shear rate was measured at 5.0 s ⁻¹ for the underfill material kept at 25 ° C. using a rheometer (TA Instruments Japan, Inc., trade name “AR2000”). The value at that time was taken as the viscosity (Pa · s). A rheometer equipped with a cone plate (diameter 40 mm, cone angle 0 °) was used and measured at a temperature of 25 ° C.

(3) Adhesive force A SiN film is formed on a silicon wafer, and a test piece is formed on the surface of the underfill material having a diameter of 3 mm and a height of 3 mm. A bond tester (DAGE, trade name “DS100”) Was used to apply a shear stress under the conditions of a head speed of 50 μm / sec and 25 ° C., and the strength (MPa) when the test piece peeled from the SiN film was defined as the adhesive strength.

(4) Voids Applying the underfill material in a cross shape to the chip mounting portion of the wiring board using a dispenser (needle diameter: 0.3 mm), and further overlapping the other cross shapes by 45 °. (Total coating amount: about 3 mg). A wiring board coated with an underfill material is placed on a stage heated to 50 ° C., a chip is mounted on the wiring board, and thermocompression bonding is performed under conditions of weight: 7.5 N, temperature / time: 260 ° C./5 seconds. Then, a semiconductor device (electronic component device) was obtained by curing the underfill material at 165 ° C. for 30 minutes.

The wiring substrate used for manufacturing the semiconductor 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 Chemical Co., Ltd., trade name), and the solder resist is AUS-308. (Taiyo Holdings Co., Ltd., trade name) and substrate plating was laminated in the order of Ni (5.0 μm), Pd (0.30 μm), and Au (0.35 μm).
A chip used for manufacturing a semiconductor device has a size of 7.3 mm in length, 7.3 mm in width, and 0.15 mm in thickness, and bumps are 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.

About each underfill material, a semiconductor device is produced by the above-described method, and observed using an ultrasonic flaw detector (Hitachi Construction Machinery Co., Ltd., trade name “AT-5500”). It was classified according to the four-stage evaluation criteria, and was used as an index of voidability.
-Evaluation criteria-
A: Void area is 1% or less of total area B: Void area is over 1% of total area and 5% or less C: Void area is over 5% of total area and 20% or less D: Void area is 20% of total area Over%

(5) Fillet crack property The semiconductor device produced by the above method was observed using a microscope, and the presence or absence of a fillet crack was classified according to the following four-stage evaluation criteria, and used as an index of fillet crack property.
-Evaluation criteria-
A: No fillet cracks are generated B: The number of fillet cracks is 1 to 2 C: The number of fillet cracks is 3 to 4 D: The number of fillet cracks is 5 or more

(6) Reflow resistance The semiconductor device manufactured by the above method was heat-dried at 120 ° C. for 12 hours, and then was subjected to moisture absorption at 30 ° C. and 70% RH for 192 hours. Then, after passing through a far-infrared heating type reflow furnace (preheating 150 ° C. to 180 ° C. for 50 seconds, peak temperature: 260 ° C., heating time of 250 ° C. or higher for 40 seconds) three times, using an ultrasonic flaw detector Observations were made. The presence or absence of peeling between the underfill material and the chip and the substrate and the presence or absence of cracks in the underfill material were confirmed, and (number of defective packages) / (number of evaluation packages) was used as an index of reflow resistance.

  Examples 1 to 12 all contain (A) a compound having an ethylenically unsaturated double bond, (B) a reaction initiator, (C) an inorganic filler, and (D) a flexible agent, and (A) The compound which has an ethylenically unsaturated double bond uses the underfill material containing the addition reaction product of (A1) epoxy resin and (meth) acrylic acid.

The following can be understood from the evaluation results shown in Tables 3 to 4.
When comparing the acrylic underfill material in Examples 1-12 and the epoxy underfill material in Comparative Example 1, the underfill material in Comparative Example 1 has a gelation time of the underfill material in Examples 1-12. It is 8 seconds longer than 2 seconds. The adhesive force of the underfill material of Comparative Example 1 is as high as 14.0 MPa compared to 10.0 MPa to 12.5 MPa of the underfill materials of Examples 1 to 12. The underfill material of Comparative Example 1 has high adhesive strength but is very inferior in voidability and reflow resistance.
On the other hand, the underfill materials of Examples 1 to 12 are shorter than the underfill material of Comparative Example 1 in terms of gelation time, have a low viscosity, and are excellent in voidability and reflow resistance. Moreover, since the underfill material of Examples 1-12 has a short gelation time, it is thought that mounting time can be shortened and productivity is improved.

  As in Examples 1 to 12, the acrylic underfill material can increase the adhesive force by containing the component (D) and the compound (A1). When the component (D) and the compound (A1) are contained, the shrinkage at the time of curing and the amount of expansion / contraction due to heat are reduced, and the adhesiveness with the electronic component is increased, so that the electrical connection between the electronic component and the wiring board It is possible to suppress the deterioration of the reliability and further improve the connection reliability of the electronic component device.

When comparing the underfill materials of Examples 1 to 12 and the underfill materials of Comparative Examples 3 to 8 that do not contain the compounds (A1) of Examples 1 to 12, the underfill materials of Comparative Examples 3 to 8 are bonded. The force is low, the reflow resistance is poor, and the void property and fillet crack property are poor.
When comparing the underfill materials of Examples 1 to 12 and the underfill materials of Comparative Examples 9 to 11 that do not contain the component (D) of Examples 1 to 12, the underfill materials of Comparative Examples 9 to 11 are bonded. The force is slightly low, the reflow resistance is inferior, and the void property and fillet crack property are also slightly inferior.
When comparing the underfill material of Examples 1 to 12 and the underfill material of Comparative Example 2 that does not contain the component (D) and the compound (A1) of Examples 1 to 12, the underfill material of Comparative Example 2 is The adhesive strength is considerably low, the reflow resistance is greatly inferior, and the fillet cracking property is also greatly inferior.

1 Semiconductor chip (electronic component)
2 Solder bump (connection part)
3 Connection pad 4 Solder resist 5 Wiring board 6 Underfill material

Claims (17)

  (A) a compound having an ethylenically unsaturated double bond, (B) a reaction initiator, (C) an inorganic filler, and (D) a flexible agent. The pre-supplied underfill material, in which the compound having an A includes an addition reaction product of (A1) an epoxy resin and (meth) acrylic acid. The pre-feed type underfill material according to claim 1, wherein the addition reaction product of the (A1) epoxy resin and (meth) acrylic acid is a compound represented by the following general formula (I-1).

(In the general formula (I-1), each of R ¹¹ independently represents a hydrogen atom or a methyl group, and each of R ¹² independently represents a C 1-18 divalent which may have a substituent. Represents a hydrocarbon group, R ¹³ represents an optionally substituted divalent hydrocarbon group having 1 to 18 carbon atoms, n represents each independently a number of 0 to 50, and m represents each Independently represents a number from 0 to 50.)   The content of the addition reaction product of the (A1) epoxy resin and (meth) acrylic acid is 5% by mass or more based on the total amount of the compound (A) having an ethylenically unsaturated double bond. Or the pre-feed type underfill material according to claim 2. The said (D) flexible agent contains the compound which has a structural unit represented by (D1) following general formula (I-7) or (I-8) in any one of Claims 1-3. The previously supplied underfill material as described.

(In General Formula (I-7), R ⁷¹ and R ⁷² each independently represent a hydrogen atom or a methyl group, and R ⁷³ and R ⁷⁴ each independently have 1 carbon atom which may have a substituent. -18 represents a monovalent hydrocarbon group, p and q each independently represent a positive number, provided that R ⁷³ and R ⁷⁴ are different from each other, R ⁷³ and R ⁷⁴ are each independently It may be denatured.)

(In General Formula (I-8), R ⁸¹ , R ⁸² , and R ⁸³ each independently represent a hydrogen atom or a methyl group, and R ⁸⁴ , R ⁸⁵ , and R ⁸⁶ each independently have a substituent. represents a monovalent hydrocarbon group of good 1 to 18 carbon atoms have been, x, y, and z each independently represent a positive number. ^However, different from each other and ^{R 84} and ^{R 85, R 85} And R ⁸⁶ are different from each other, and R ⁸⁴ , R ⁸⁵ , and R ⁸⁶ may each independently be partially modified.)   The tip according to claim 4, wherein the compound (D1) having a structural unit represented by the general formula (I-7) or (I-8) has a weight average molecular weight of 5,000 to 1,000,000. Supply type underfill material.   The content ratio of the compound represented by (D1) general formula (I-7) or (I-8) is 1% by mass or more based on the total amount of the pre-feed type underfill material. 5. The pre-feed type underfill material according to 5.   7. The compound according to claim 1, wherein the compound (A) having an ethylenically unsaturated double bond includes a compound having two or more ethylenically unsaturated double bonds in one molecule. Pre-feed type underfill material.   The content of the compound having two or more ethylenically unsaturated double bonds in one molecule is 30% by mass or more based on the total amount of the compound (A) having an ethylenically unsaturated double bond. The pre-feed type underfill material according to 7.   The pre-feeding under type according to any one of claims 1 to 8, wherein the compound (A) having an ethylenically unsaturated double bond contains (A2) tricyclodecane dimethylol di (meth) acrylate. Fill material.   The content of the (A2) tricyclodecane dimethylol di (meth) acrylate is 20% by mass or more based on the total amount of the compound (A) having an ethylenically unsaturated double bond. Pre-feed type underfill material. 11. The compound according to claim 1, wherein the compound (A) having an ethylenically unsaturated double bond includes (A3) a (meth) acrylate compound represented by the following general formula (I-2). The pre-feed type underfill material described in 1.

(In General Formula (I-2), each R ²¹ independently represents a hydrogen atom or a methyl group, and R ²² represents a C 1-18 divalent hydrocarbon group which may have a substituent. And r and s each independently represent a number from 0 to 50.)   (A3) The content rate of the (meth) acrylate compound represented by the general formula (I-2) is 10% by mass or more based on the total amount of the compound (A) having an ethylenically unsaturated double bond. The pre-feed type underfill material according to claim 11.   The pre-feed type underfill material according to any one of claims 1 to 12, wherein the (B) reaction initiator contains an organic peroxide.   The pre-feed type underfill material according to any one of claims 1 to 13, wherein a volume average particle size of the (C) inorganic filler is 0.1 µm to 10 µm.   The content rate of said (C) inorganic filler is 10 mass% or more with respect to the whole quantity of a pre-feed type underfill material, The pre-feed type underfill material of any one of Claims 1-14. . 16. The device according to claim 1, wherein at least one surface selected from the group consisting of a surface of the electronic component facing the wiring substrate and a surface of the wiring substrate facing the electronic component is selected. A supply step of supplying the pre-feed type underfill material described in 1.
A method for manufacturing an electronic component device, comprising: a connecting step of connecting the electronic component and the wiring board through a connecting portion and curing the pre-supplied underfill material after the supplying step. Electronic components,
A wiring board that is disposed opposite to the electronic component and connected to the electronic component via a connection portion;
The electronic component apparatus which has a hardened | cured material of the pre-feed type underfill material of any one of Claims 1-15 arrange | positioned between the said electronic component and the said wiring board.