JP2016178104A - Underfill material, method for manufacturing electronic component device, and electronic component device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide: an underfill material which is applied to a pre-coating method, enables the shortening of a curing time, produces fewer voids, and is superior in adhesiveness with an electronic component; a method for manufacturing an electronic component device, which enables the manufacturing of an electronic component device superior in connection reliability by use of such an underfill material; and an electronic component device which is superior in connection reliability and fewer in voids produced.SOLUTION: An underfill material is used in an electronic component device manufacturing method for manufacturing an electronic component device by electrically connecting an electronic component with a wiring board. The method comprises: an application step for applying the underfill material to at least one of a face of the electronic component on the side where the electronic component fronts a wiring board, and a face of the wiring board on the side where the wiring board fronts the electronic component; and a connection step for connecting the electronic component with the wiring board through a connection part and then, curing the underfill material. The underfill material comprises (A) a compound having an ethylene unsaturated double bond, (B) a reaction initiator, (C) an inorganic filler and (D) an ion-trap agent.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an 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), liquid epoxy resin compositions at room temperature (25 ° C.) are widely used as sealing materials. It is used. 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 forming surface is not sufficiently protected, so moisture and ionic impurities can easily enter.In flip chip mounting, the electronic component and the wiring board may have different coefficients of thermal expansion, so the connection part Thermal stress may occur. 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 prior application method in which the connection between the electronic component and the wiring substrate and the curing reaction of the underfill material are collectively performed when the electronic component is first applied onto the wiring substrate and thermocompression bonded to connect the electronic component to the wiring substrate.

If the underfill material used in the pre-coating method is low in curability, the time required for thermocompression bonding becomes long, and the volatile matter generated from the electronic component device, underfill material, etc. tends to cause voids. The underfill material used is preferably curable in a short time.
If voids are present in the underfill material, the reliability of connection due to thermal stress and the reliability of moisture resistance due to the ingress of moisture and ionic impurities are reduced, so generation of voids in the underfill material is suppressed. Is required.

  As a method for enabling the epoxy resin composition to be cured for a short time, 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 by coating with (for example, see Patent Document 2) has been reported.

  Moreover, radical reaction is mentioned as reaction which can be hardened | cured for a short time. 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).

  In recent years, as electronic components are highly integrated, multifunctional, and multi-pin, bumps have been reduced in diameter and pitch, and when electronic components and wiring boards are connected using a reflow furnace. In addition, there are cases in which the connection portion is broken by the stress generated during cooling. For this reason, there is an increasing demand for a pre-coating underfill material capable of connecting an electronic component to a wiring board and protecting the connection portion with the underfill material.

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

  However, even when an epoxy resin composition that can be cured for a short time is used as an underfill material for a pre-coating method, the reaction rate is slow, and a long time is required for curing by thermocompression bonding, and voids are likely to occur. Therefore, an electronic component device obtained by 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 for a short time, but has low adhesion to electronic components, and was obtained using such an underfill material. The electronic component device has insufficient connection reliability.

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

  The present invention has been made in view of such circumstances, and is applied to a pre-coating method, can reduce the curing time, has less voids, and has excellent adhesion to electronic components, Using this underfill material, an electronic component device manufacturing method capable of manufacturing an electronic component device excellent in electrical connection reliability, and an electronic component device excellent in electrical connection reliability and generating less voids are provided. The issue is to provide.

  As a result of intensive studies to solve the above problems, the present inventors have found that in the underfill material used in the pre-coating method, a compound having an ethylenically unsaturated double bond, a reaction initiator, an inorganic filler, and It has been found that the above problems can be solved by using an ion trapping agent, and the present invention has been completed.

The present invention includes the following aspects.
The present invention provides [1] an applying step of applying an underfill material to at least one of the surface of the electronic component facing the wiring substrate or the surface of the wiring substrate facing the electronic component; After the applying step, the electronic component and the wiring board including the connecting step of connecting the electronic component and the wiring board via the connecting portion and curing the underfill material are electrically connected via the connecting portion. It is an underfill material used in a manufacturing method of an electronic component device for manufacturing an electronic component device by connecting,
The underfill material relates to an underfill material containing (A) a compound having an ethylenically unsaturated double bond, (B) a reaction initiator, (C) an inorganic filler, and (D) an ion trap agent.
The present invention also relates to [2] the underfill material according to [1], wherein the ion trapping agent (D) is a hydrotalcite compound.
Moreover, the present invention provides [3] the under (D) ion trapping agent according to the above [1] or [2], wherein the ion-trapping agent is an unfired hydrotalcite compound represented by the following general formula (I-1): It relates to the fill material.

（ａ、ｂ、ｃ、ｄ、ｍはそれぞれ０以上の整数）
また、本発明は、[４] 前記（Ｄ）イオントラップ剤の含有量が、アンダーフィル材の全量に対して０．１質量％以上である上記［１］〜［３］のいずれか１項に記載のアンダーフィル材に関する。
また、本発明は、[５] 前記（Ａ）エチレン性不飽和二重結合を有する化合物が、１分子中にエチレン性不飽和二重結合を２つ以上含む化合物を含む上記［１］〜［４］のいずれか１項に記載のアンダーフィル材に関する。
また、本発明は、[６] 前記１分子中にエチレン性不飽和二重結合を２つ以上含む化合物の含有率が、前記（Ａ）エチレン性不飽和二重結合を有する化合物の全量に対して３０質量％以上である上記［５］に記載のアンダーフィル材に関する。
また、本発明は、[７] 前記（Ａ）エチレン性不飽和二重結合を有する化合物が、（Ａ１）トリシクロデカンジメチロールジ（メタ）アクリレートを含む上記［１］〜［６］のいずれか１項に記載のアンダーフィル材に関する。
また、本発明は、[８] 前記（Ａ１）トリシクロデカンジメチロールジ（メタ）アクリレートの含有率が、前記（Ａ）エチレン性不飽和二重結合を有する化合物の全量に対して２０質量％以上である上記［７］に記載のアンダーフィル材に関する。
また、本発明は、[９] 前記（Ａ）エチレン性不飽和二重結合を有する化合物が、（Ａ２）下記一般式(Ｉ−２)で表される（メタ）アクリレート化合物を含む上記［１］〜［６］のいずれか１項に記載のアンダーフィル材に関する。

(A, b, c, d, m are each integers of 0 or more)
Moreover, this invention is [1] Any one of said [1]-[3] whose content of the said (D) ion trap agent is 0.1 mass% or more with respect to the whole quantity of an underfill material. The underfill material described in 1.
The present invention also provides [5] [1] to [1] above, wherein the compound (A) having an ethylenically unsaturated double bond includes a compound having two or more ethylenically unsaturated double bonds in one molecule. 4]. The underfill material according to any one of [4].
The present invention also provides [6] wherein the content of the compound having two or more ethylenically unsaturated double bonds in one molecule is based on the total amount of the compound (A) having an ethylenically unsaturated double bond. It is related with the underfill material as described in said [5] which is 30 mass% or more.
In addition, the present invention provides [7] any of the above [1] to [6], wherein the compound (A) having an ethylenically unsaturated double bond contains (A1) tricyclodecane dimethylol di (meth) acrylate. It relates to the underfill material according to item 1.
The present invention also provides: [8] The content of the (A1) tricyclodecane dimethylol di (meth) acrylate is 20% by mass with respect to the total amount of the compound (A) having an ethylenically unsaturated double bond. It is related with the underfill material as described in said [7].
Further, the present invention provides: [9] The above [1], wherein the compound (A) having an ethylenically unsaturated double bond includes (A2) a (meth) acrylate compound represented by the following general formula (I-2): ] It is related with the underfill material of any one of [6].

（一般式（Ｉ−２）中、Ｒ^２１はそれぞれ独立に、水素原子又はメチル基を表し、Ｒ^２２は置換基を有していてもよい炭素数１〜１８の２価の炭化水素基を表し、ｐはそれぞれ独立に、０〜５０の整数を表し、ｑはそれぞれ独立に、０〜５０の整数を表す。）
また、本発明は、[１０] （Ａ２）上記一般式(Ｉ−２)で表される（メタ）アクリレート化合物の含有率が、前記（Ａ）エチレン性不飽和二重結合を有する化合物の全量に対して１０質量％以上である上記［９］に記載のアンダーフィル材に関する。
また、本発明は、[１１] 前記（Ｂ）反応開始剤が、有機過酸化物を含む上記［１］〜［１０］のいずれか１項に記載のアンダーフィル材に関する。
また、本発明は、[１２] 前記（Ｃ）無機充填剤の体積平均粒子径が、０．１〜１０μｍである上記［１］〜［１１］のいずれか１項に記載のアンダーフィル材に関する。
また、本発明は、[１３] 前記（Ｃ）無機充填剤の含有率が、アンダーフィル材の全量に対して１０質量％以上である上記［１］〜［１２］のいずれか１項に記載のアンダーフィル材に関する。

(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 each p independently represents an integer of 0 to 50, and q independently represents an integer of 0 to 50.)
Further, the present invention provides [10] (A2) wherein the content of the (meth) acrylate compound represented by the general formula (I-2) is the total amount of the compound (A) having an ethylenically unsaturated double bond. It is related with the underfill material as described in said [9] which is 10 mass% or more.
[11] The present invention also relates to the underfill material according to any one of [1] to [10], wherein the (B) reaction initiator includes an organic peroxide.
Moreover, this invention relates to the underfill material of any one of said [1]-[11] whose volume average particle diameter of [12] said (C) inorganic filler is 0.1-10 micrometers. .
Moreover, this invention is [13] Any one of said [1]-[12] whose content rate of the said (C) inorganic filler is 10 mass% or more with respect to the whole quantity of an underfill material. Related to underfill materials.

Further, the present invention provides [14] the above [1] to [13] on at least one of the surface of the electronic component facing the wiring substrate or the surface of the wiring substrate facing the electronic component. An applying step of applying the underfill material according to any one of the above, and a connecting step of connecting the electronic component and the wiring board via a connecting portion after the applying step and curing the underfill material. And a manufacturing method of an electronic component device.
The present invention also relates to [15] an electronic component device manufactured using the underfill material according to any one of [1] to [13].

  According to the present invention, an underfill material that is applied to a pre-coating method, can shorten the curing time, has less voids, and has excellent adhesion to an electronic component, and using this underfill material, An electronic component device manufacturing method capable of manufacturing an electronic component device excellent in connection reliability, and an electronic component device excellent in electrical connection reliability and generating less voids can be provided.

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

Hereinafter, the present invention will be described in detail.
In the present specification, a numerical range indicated using “to” indicates a range including the numerical values described before and after “to” as the minimum value and the maximum value, respectively.
In the present specification, the amount of each component in the composition means the total amount of the plurality of substances present in the composition unless there is a specific notice when there are a plurality of substances corresponding to each component in the composition. To do.

In this specification, “room temperature” means 25 ° C.
In this specification, “liquid at room temperature” means a state in which fluidity is exhibited at 25 ° C.
In the present specification, the “liquid” means a substance that exhibits fluidity and viscosity and has a viscosity of 0.0001 to 1000 Pa · s at 25 ° C., which is a measure of viscosity.

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 °).

  Further, in this specification, the “underfill material” means 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. The material for filling the gap (gap) between the bump-connected electronic component and the wiring substrate and protecting the connection portion between the electronic component and the wiring substrate from temperature, humidity, and mechanical external force.

In this specification, the (meth) acryloyl group means both an acryloyl group and a methacryloyl group, or either an acryloyl group or a methacryloyl group.
In this specification, the (meth) acryloyloxy group means both an acryloyloxy group and a methacryloyloxy group, or either an acryloyloxy group or a methacryloyloxy group.

  Hereinafter, the underfill material, the manufacturing method of an electronic component device, and the electronic component device of the present invention will be described in order.

[Underfill material]
First, the underfill material of the present invention will be described.
The underfill material of the present invention is an underfill material used in the method of manufacturing an electronic component device of the present invention in which an electronic component device is manufactured by electrically connecting an electronic component and a wiring board via a connecting portion. , (A) a compound having an ethylenically unsaturated double bond, (B) a reaction initiator, (C) an inorganic filler, and (D) an ion trap agent, and the underfill material is a wiring board in an electronic component An applying step of applying an underfill material to at least one surface of the surface facing the electronic component or the surface facing the electronic component in the wiring board, and connecting the electronic component and the wiring board after the applying step And a connecting step of curing the underfill material.

By adopting the above configuration, the underfill material of the present invention can shorten the curing time of the underfill material, and can produce a cured product that is less likely to generate voids and has excellent adhesion to electronic components. 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 the present invention 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 surmised that the underfill material of the present invention has a higher reaction rate and can shorten the curing time than a conventional underfill material containing an epoxy resin and an epoxy resin curing agent. By shortening the curing time of the underfill material, it is considered that the volatile matter generated from the underfill material or the like can suppress the generation of voids.
Moreover, it is guessed that the underfill material of this invention can improve adhesiveness with a base material by containing (D) ion trap agent. 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. In addition, it is considered that the inclusion of (D) an ion trapping agent reduces the amount of ion impurities in the cured product and improves electrical characteristics such as connection reliability and Bias-HAST resistance.

As described above, the underfill material of the present invention is a pre-applied underfill material.
The viscosity of the underfill material of the present invention is preferably 0.01 to 1000 Pa · s at 25 ° C., more preferably 0.1 to 500 Pa · s, and 1.0 to 100 Pa · s. Is more preferable. The method for measuring the viscosity of the underfill material in the present invention is as described above.

Moreover, it is preferable that it is 0.1-100, and 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 fluctuation index of the underfill material in the present invention 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. Specifically, the “thickening index” is measured as a shear viscosity at a temperature of 25 ° C. using a rotary shear viscometer equipped with a cone plate (diameter 40 mm, cone angle 0 °).

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

<(A) Compound having an ethylenically unsaturated double bond>
The underfill material of this invention contains the compound which has an ethylenically unsaturated double bond of (A) component.
The compound (A) having an ethylenically unsaturated double bond that can be used in the present invention is used as an underfill material used for manufacturing electronic component devices as long as the effects of the present invention are achieved. The compound is not particularly limited as long as it is a compound having a general ethylenically unsaturated double bond.

  (A) As a compound which has an ethylenically unsaturated double bond, the compound which has a liquid ethylenically unsaturated double bond at room temperature (25 degreeC) so that the underfill material of this invention may be liquid at room temperature. A compound having a solid ethylenically unsaturated double bond at room temperature (25 ° C.) and a compound having a liquid ethylenically unsaturated double bond at room temperature (25 ° C.) may be used in combination. .

  (A) As a compound having an ethylenically unsaturated double bond, even if it is a compound having only one ethylenically unsaturated double bond in one molecule, it has an ethylenically unsaturated double bond in one molecule. It may be a compound having two or more. In the following, the case of having only one ethylenically unsaturated double bond in one molecule is referred to as monofunctional, and the case of having two ethylenically unsaturated double bonds in one molecule is referred to as bifunctional. The case of having 3 or more ethylenically unsaturated double bonds in one molecule may be referred to as polyfunctional.

  Examples of the compound (A) 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) acrylic compounds Or an allyl nadiimide compound is preferable and a (meth) acryl 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 from the viewpoint of flexibility of the cured product, not more than 10 in one molecule. The compound which has a (meth) acryloyl group is mentioned, The compound which has 2 or more (meth) acryloyl groups in 1 molecule is preferable, The compound which has 6 or less (meth) acryloyl groups in 1 molecule is more preferable . The (meth) acryloyl group is more 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 void properties and the strength of the cured product.

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,
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 Diacrylic compounds such as diacrylate Functional acrylic compound,
Polyfunctional acrylic compounds 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 isophoricisocyanate, a reaction product of dipentaerythritol penta (meth) acrylate and hexamethylene diisocyanate, and an ethylenically unsaturated disilane in one molecule. 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 heavy bond and 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. Can be 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 divalent hydrocarbon group having 1 to 18 carbon atoms 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. It is preferable that it is a -18 alicyclic hydrocarbon group or a C6-C18 aromatic hydrocarbon group.

  As an 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), N, N′-m-xylylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide) ( Maruzen Petrochemical Co., Ltd., trade name: BANI-X) is available as a commercial product.

  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 divalent hydrocarbon group having 1 to 18 carbon atoms which may have a substituent.

  In general formula (I-6), n is 0 or an integer of 1 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. It is preferably a hydrogen group, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms.

  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) and m-phenylene bismaleimide (Daiwa Kasei Kogyo). 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), 1,6'-bis Maleimide- (2,2,4-trimethyl) hexane (Daiwa Kasei Kogyo Co., Ltd., trade name: BMI-TMH) ) Is commercially available.

  As the bismaleimide compound represented by the general formula (I-6), for example, phenylmethane maleimide (Daiwa Kasei Kogyo Co., Ltd., trade name: BMI-2000) is commercially available.

  In the present invention, the compound (A) having an ethylenically unsaturated double bond is, as a compound having another ethylenically unsaturated double bond, in one molecule among the above compounds from the viewpoint of adhesiveness and voidability. It is preferable to include a compound having two or more ethylenically unsaturated double bonds.

The content of the compound having two or more ethylenically unsaturated double bonds in one molecule is preferably 30% by mass or more based on the total amount of the compound (A) having an ethylenically unsaturated double bond. , 40% by mass or more, more preferably 50% by mass or more. There exists a tendency for the adhesiveness and void property of an underfill material to improve that content of the compound containing 2 or more of ethylenically unsaturated double bonds is 30 mass% or more.
The content of the compound having two or more ethylenically unsaturated double bonds in one molecule is preferably 95% by mass or less based on the total amount of the compound (A) having an ethylenically unsaturated double bond. More preferably, it is 90 mass% or less.

As a compound containing two or more ethylenically unsaturated double bonds in one molecule, it is more preferable to contain the above-mentioned bifunctional (meth) acryl compound, and (A1) tricyclodecane dimethylol di (meth) acrylate is used. It is more preferable to include.
When (A1) tricyclodecane dimethylol di (meth) acrylate is used as a compound containing two or more ethylenically unsaturated double bonds in one molecule, the content of tricyclodecane dimethylol di (meth) acrylate is (A) It is preferable that it is 20 mass% or more with respect to the whole quantity of the compound which has an ethylenically unsaturated double bond, It is more preferable that it is 25 mass% or more, It is further that it is 30 mass% or more. preferable. There exists a tendency for the void property of an underfill material and the intensity | strength of hardened | cured material to improve that content of tricyclodecane dimethylol di (meth) acrylate is 20 mass% or more.
The content of tricyclodecane dimethylol di (meth) acrylate is preferably 80% by mass or less, and 75% by mass or less, based on the total amount of the compound (A) having an ethylenically unsaturated double bond. Is more preferable, and it is still more preferable that it is 70 mass% or less.

  As a compound containing two or more ethylenically unsaturated double bonds in one molecule, it is more preferable to contain the above-mentioned bifunctional (meth) acryl compound, and (A2) is represented by the following general formula (I-2) It is further preferable to contain a (meth) acrylate compound.

（一般式（Ｉ−２）中、Ｒ^２１はそれぞれ独立に、水素原子又はメチル基を表し、Ｒ^２２は置換基を有していてもよい炭素数１〜１８の２価の炭化水素基を表し、ｐはそれぞれ独立に、０〜５０の整数を表し、ｑはそれぞれ独立に、０〜５０の整数を表す。）

(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 each p independently represents an integer of 0 to 50, and q independently represents an integer of 0 to 50.)

When (A2) the (meth) acrylate compound represented by the above general formula (I-2) is used as a compound containing two or more ethylenically unsaturated double bonds in one molecule, the above general formula (I-2 ) The content of the (meth) acrylate compound represented by (A) is preferably 10% by mass or more and 15% by mass or more with respect to the total amount of the compound (A) having an ethylenically unsaturated double bond. It is more preferable, and it is still more preferable that it is 20 mass% or more. There exists a tendency for the void property of an underfill material and the intensity | strength of hardened | cured material to improve that content of the (meth) acrylate compound represented by the said general formula (I-2) is 10 mass% or more.
(A2) The content rate of the (meth) acrylate compound represented by the general formula (I-2) is 80% by mass or less based on the total amount of the compound (A) having an ethylenically unsaturated double bond. It is preferably 75% by mass or less, and more preferably 70% by mass or less.

<(B) Reaction initiator>
The underfill material of this invention contains the reaction initiator of (B) component.
The reaction initiator that can be used in the present invention is not particularly limited, and a generally used reaction initiator can be used in an underfill material used for manufacturing an electronic component device. Here, the reaction initiator in the present invention means a compound capable of initiating a curing reaction of a compound having an ethylenically unsaturated double bond by radicals generated in applying energy such as heat and light. Moreover, either the solid or liquid reaction initiator may be used at room temperature (25 ° C.), or both may be used in combination so that the underfill material of the present invention becomes liquid at room temperature.

  Examples of the reaction initiator in the present invention include organic peroxides, azo compounds, water-soluble catalysts, redox catalysts formed by combining peroxides or persulfates and reducing agents. Among these, from the viewpoint of storage stability, the reaction initiator is preferably an organic peroxide.

  Examples of organic peroxides 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-butylperoxide). Peroxyketals such as oxy) cyclohexyl) propane, p-menthane hydroperoxide, diisopropylbenzene hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, cumene hydroperoxide, t-butyl hydroperoxide , Hydroperoxides such as di-t-butyl peroxide, di (2-t-butylperoxyisopropyl) benzene, dicumyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) Hexane, t-butyl Dialkyl peroxides such as ruperoxide, di-t-hexyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne-3, dibenzoyl peroxide, di (4-methylbenzoyl) ) Diacyl peroxide such as peroxide, peroxydicarbonate such as di-n-propyl peroxydicarbonate, diisopropyl peroxydicarbonate, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, t -Peroxyesters such as -hexylperoxybenzoate and t-butylperoxybenzoate.

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

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

  The content of the reaction initiator of the present invention is preferably 0.1 to 20% by mass with respect to the total amount of the compound (A) having an ethylenically unsaturated double bond (component (A)), and is curable. From this viewpoint, the content is more preferably 0.5 to 10% by mass. When the content of the reaction initiator is 0.1% by mass or more, the reaction proceeds more sufficiently, and when it is 20% by mass or less, the storage stability of the underfill material is further improved.

<(C) Inorganic filler>
The underfill material of this invention contains the inorganic filler of (C) component.
The inorganic filler that can be used in the present invention is not particularly limited as long as it is an inorganic filler that is generally used for underfill materials used for manufacturing electronic component devices. 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. These inorganic fillers may be used alone or in combination of two or more.

Among them, 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 the present invention, that the silica is spherical means that the sphericity satisfies the condition of 0.7 or more. As a method for 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 in the present invention is not particularly limited as long as the effect of the present invention is achieved. The volume average particle diameter of the inorganic filler is preferably 0.1 to 10 μm, more preferably 0.15 to 7.5 μm, and still more preferably 0.20 to 5.0 μm.
If the volume average particle diameter of the inorganic filler is 10 μm or less, the permeability and fluidity of the underfill material into the fine gaps are improved, and there is a tendency that generation of voids and unfilling of the underfill material are less likely to occur. . Further, the inorganic filler is less likely to bite into the connection part between the electronic component and the wiring board, and connection failure tends to be less likely 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 invention, the “volume average particle diameter” of the inorganic filler means that the cumulative distribution is 50% in the cumulative distribution represented by the cumulative number of degrees, where the particle diameter is a class and the volume is a frequency using the following method. Mean particle size. As a method for 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, small angle X-ray scattering, an electron microscope, an atomic force microscope, etc. And a method of measuring the particle size 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 in the present invention is not particularly limited as long as the effect of the present invention is achieved. 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 of the wiring board and connection failure is unlikely to occur.

  The minimum particle diameter of the inorganic filler in the present invention is not particularly limited as long as the effect of the present invention is achieved. The minimum particle size of the inorganic filler is 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 the inorganic filler in the present invention is not particularly limited as long as the effect of the present invention is achieved. The content of the inorganic filler is 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. When the content of the inorganic filler 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 further improved. The content of the inorganic filler is preferably 80% by mass or less, more preferably 75% by mass or less, and still more preferably 70% by mass or less with respect to the total amount of the underfill material.

  As a method for measuring the content of the inorganic filler, for example, a method of calculating from the ash content obtained as a residue after treating the underfill material before or after curing at a high temperature of 800 ° C. or higher in a muffle furnace or the like is used. Can do.

<(D) Ion trap agent>
The underfill material of this invention contains the ion trap agent of (D) component.
The ion trapping agent that can be used in the present invention is not particularly limited as long as it is an ion trapping agent that is generally used for an underfill material used for manufacturing an electronic component device. Examples of the ion trapping agent include hydrotalcite compounds, bismuth compounds, hydrated oxides of elements selected from magnesium, aluminum, titanium, zirconium, antimony, and the like. The ion trapping agent is preferably a hydrotalcite compound, and more preferably an unfired hydrotalcite compound represented by the following general formula (I-1).

（ａ、ｂ、ｃ、ｄ、ｍはそれぞれ０以上の整数）
ハイドロタルサイト化合物は、層状の結晶構造を有し、ひとつひとつの結晶片は葉片状あるいは鱗状を呈している。構造の主骨格［Ｍｇ_６Ａｌ_２（ＯＨ）_１６］はシート状の金属水酸化物であり、ハイドロタルサイト化合物は、構造式［Ｍ^２＋ _１−ｘＭ^３＋ _ｘ（ＯＨ）_２][Ａ^ｎ _ｘ／ｎ・ｍＨ_２Ｏ］で表される様々な化合物のうちのひとつである。Ｍ^２＋とＭ^３＋は２価および３価の金属イオンを、Ａ^ｎ _ｘ／ｎは層間陰イオンを表し、［Ｍ^２＋ _１−ｘＭ^３＋ _ｘ（ＯＨ）_２］が水酸化物シートで、金属イオンを６つの（ＯＨ）が取り囲んで形成する八面体が互いに稜を共有することによって作られている。水酸化物シートが何枚も重なってハイドロタルサイト化合物の層状構造を形成し、シートとシートの間（層間）には陰イオンと水分子が入っている。ハイドロタルサイト化合物の水酸化物シートは２価の金属の一部を３価の金属が置き換えているので全体として正に荷電する。静電的なバランスは、層間に陰イオンが取り込まれることによって保たれるとされている。この特徴を利用してイオントラップ剤として用いることが可能となる。ハイドロタルサイト化合物を焼成することで比表面積を増大させ、化合物表面でのトラップを可能にした焼成ハイドロタルサイト化合物は、ハイドロタルサイト化合物の特徴である層構造が破壊されてしまうため、本発明で用いるイオントラップ剤は未焼成ハイドロタルサイトのほうがより好ましい。
本発明で用いる未焼成ハイドロタルサイト化合物は、２．４≦Ｍｇ／Ａｌ（２．４≦ａ／ｂ）となるようにＭｇ塩とＡｌ塩のモル比を調整し作製する。得られた未焼成ハイドロタルサイト化合物は、焼成を施していないもので、Ｘ線回折において、層方向ピークである００１面、００２面ピークが共に５〜４５°付近におよそ等間隔で観察される。
未焼成ハイドロタルサイト化合物の二次粒子径は、２５０μｍ以上であることが好ましく、また、ＢＥＴ比表面積が１０〜１００ｍ^２/ｇが好ましい。粒度測定には、ふるい分析装置に比べ再現性に優れ短時間で測定可能な、レーザー回折／散乱式粒度分布測定装置を用いるのが好ましい。比表面積は、正確に単分子吸着量が測定可能なＢＥＴ法を用いるのが好ましい。
イオントラップ剤は、１種単独で用いても２種以上を組み合わせて用いてもよい。
本発明のアンダーフィル材がイオントラップ剤を含有する場合、イオントラップ剤の含有率は、アンダーフィル材の全量に対して、０．１〜５．０質量％であることが好ましく、１．０〜３．０質量％であることがより好ましい。また、イオントラップ剤の体積平均粒子径は０．１〜３．０μｍであることが好ましく、最大粒子径は１０μｍ以下であることが好ましい。
なお、イオントラップ剤の平均粒子径及び最大粒子径は、前記無機充填剤と同様の方法を用いて測定される。

(A, b, c, d, m are each integers of 0 or more)
The hydrotalcite compound has a layered crystal structure, and each crystal piece has a leaf shape or a scale shape. The main skeleton [Mg ₆ Al ₂ (OH) ₁₆ ] of the structure is a sheet-like metal hydroxide, and the hydrotalcite compound is represented by the structural formula [M ²⁺ _1-x M ³⁺ _x (OH) ₂ ] [A ^n. _{x / n} · mH ₂ O]. M ²⁺ and M ³⁺ represent divalent and trivalent metal ions, ^An _{x / n} represents an interlayer anion, and [M ²⁺ _1-x M ³⁺ _x (OH) ₂ ] is a hydroxide sheet, An octahedron formed by six (OH) surrounding an ion is created by sharing a ridge with each other. A number of hydroxide sheets overlap to form a layered structure of the hydrotalcite compound, and anions and water molecules are contained between the sheets (interlayers). The hydroxide sheet of the hydrotalcite compound is positively charged as a whole because a part of the divalent metal is replaced by the trivalent metal. The electrostatic balance is said to be maintained by incorporating anions between layers. Using this feature, it can be used as an ion trapping agent. The calcined hydrotalcite compound that increases the specific surface area by calcining the hydrotalcite compound and enables trapping on the compound surface destroys the layer structure that is characteristic of the hydrotalcite compound. The ion trapping agent used in is more preferably uncalcined hydrotalcite.
The uncalcined hydrotalcite compound used in the present invention is prepared by adjusting the molar ratio of Mg salt to Al salt so that 2.4 ≦ Mg / Al (2.4 ≦ a / b). The obtained uncalcined hydrotalcite compound is not calcined, and in X-ray diffraction, the 001 plane and 002 plane peaks, which are layer direction peaks, are observed at approximately equal intervals in the vicinity of 5 to 45 °. .
The secondary particle size of the unfired hydrotalcite compound is preferably 250 μm or more, and the BET specific surface area is preferably 10 to 100 m ² / g. For the particle size measurement, it is preferable to use a laser diffraction / scattering particle size distribution measuring device which is excellent in reproducibility compared with a sieve analyzer and can be measured in a short time. For the specific surface area, it is preferable to use the BET method capable of accurately measuring the amount of adsorbed single molecules.
An ion trap agent may be used individually by 1 type, or may be used in combination of 2 or more type.
When the underfill material of this invention contains an ion trap agent, it is preferable that the content rate of an ion trap agent is 0.1-5.0 mass% with respect to the whole quantity of an underfill material, and 1.0 More preferably, it is -3.0 mass%. The volume average particle size of the ion trapping agent is preferably 0.1 to 3.0 μm, and the maximum particle size is preferably 10 μm or less.
The average particle size and the maximum particle size of the ion trapping agent are measured using the same method as that for the inorganic filler.

<Various additives>
The underfill material of the present invention comprises (A) a compound having an ethylenically unsaturated double bond, (B) a reaction initiator and (C) an inorganic filler, and (D) an ion trapping agent, as necessary. Furthermore, various additives may be included.

  Examples of the additive include various additives such as a coupling agent, a flux agent, a flexible agent, a thixotropic agent, and a surfactant. The underfill material of the present invention 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 the present invention 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 invention is not particularly limited as long as the effects of the present invention are achieved.

  As the coupling agent, 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, vinyl silane, and the like. Examples thereof include silane compounds, titanium compounds, aluminum chelates, and aluminum-zirconium compounds.

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

  When the underfill material of this invention contains a coupling agent, it is preferable that the content rate of a coupling agent is 0.05-5 mass% of an inorganic filler [(C) component], 0.1-0.1%. More preferably, it is 2.5 mass%. If the content of the coupling agent is 0.05% by mass or more, the adhesiveness between the cured product of the underfill material of the present invention and the wiring board or electronic component tends to be further improved, and the content of the coupling agent If it is 5 mass% or less, there exists a tendency for a moldability and generation | occurrence | production of a void to be reduced more.

(Flux agent)
The underfill material of the present invention may contain a flux agent as necessary to impart a flux function.
As the fluxing agent in the present invention, a hydrohalic acid amine salt or the like conventionally used in this technical field may be used. In addition, from the viewpoint of electrical characteristics, preferred fluxing agents in the present invention include compounds having a phenolic hydroxyl group and a carboxy group such as hydroxybenzoic acid, acid anhydrides containing carboxyxyl groups such as trimellitic acid, abitienic acid, and adipine Examples thereof include organic acids such as acid, ascorbic acid, citric acid, 2-furancarboxylic acid and malic acid, and compounds containing two or more alcoholic hydroxyl groups in one molecule.

  The underfill material of the present invention may contain one flux agent alone or two or more kinds.

  When the underfill material of the present invention contains a fluxing agent, the content of the fluxing agent is not particularly limited as long as the fluxing function is manifested. The content of the fluxing agent is preferably 0.1 to 10% by mass and more preferably 0.5 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 of the present invention and the connection portion of the wiring board and electronic component is increased, and the connectivity between the wiring board and electronic component is further improved. If the content of the fluxing agent is 10% by mass or less, generation of voids is further reduced and reliability such as migration resistance tends to be improved.

(Flexible agent)
The underfill material of the present invention may contain a flexible agent as necessary from the viewpoint of improving thermal shock resistance and reducing stress on electronic components. As the flexible agent in the present invention, styrene-butadiene rubber (SBR), nitrile-butadiene rubber (NBR), and butadiene rubber (BR) which are generally used for underfill materials used for manufacturing electronic component devices are used. ), Urethane rubber (UR), acrylic rubber (AR) and other rubber particles, polybutadiene, maleic acid polybutadiene, epoxidized polybutadiene, hydrogenated polybutadiene and other liquid polybutadiene compounds at room temperature, polymethylmethacrylic acid and polybutylacrylic acid Silicone rubber particles obtained by crosslinking linear polyorganosiloxane such as diblock copolymer, triblock copolymer, polydimethylsiloxane, polymethylphenylsiloxane, polydiphenylsiloxane, etc .; the surface of the silicone rubber particle is made of silicone resin Coat Things, a core comprising a shell of an organic polymer core and an acrylic resin of the resulting solid silicone particles in the emulsion polymerization or the like - such as shell polymer particles.
The underfill material of the present invention may contain a flexible agent alone or in combination of two or more.
Among the flexible agents, from the viewpoint of viscosity, polybutadiene compounds that are liquid at room temperature, diblock copolymers and triblock copolymers of polymethylmethacrylic acid and polybutylacrylic acid, solid silicone particle cores and acrylic resins, etc. Core-shell polymer particles containing an organic polymer shell are preferred, and from the viewpoint of adhesion, a polybutadiene compound which is liquid at room temperature, a diblock copolymer or a triblock copolymer of polymethylmethacrylic acid and polybutylacrylic acid It is particularly preferred that

  When the underfill material of this invention contains a flexible agent, it is preferable that the content rate of a flexible agent is 1-30 mass% with respect to the whole quantity of an underfill material, and it is 2-20 mass%. More preferred. When the content of the flexible agent is 1% by mass or more, the effect of reducing stress obtained by the inclusion of the flexible agent tends to be further improved, and when the content of the flexible agent is 30% by mass or less The expected viscosity of the fill material is maintained and the moldability tends to be maintained.

(Thixotropic agent)
The underfill material of the present invention may contain a thixotropic agent as necessary from the viewpoint of improving shape retention. As a thixotropic agent, 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, an amide wax synthesized from a vegetable oil fatty acid and an amine Examples thereof include a compound, a salt of a long-chain polyaminoamide and an acid polymer, an unsaturated polycarboxylic acid polymer, fine powder 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 applied to a wiring board or electronic component, if the underfill material flows without being able to maintain its shape, it tends to entrain voids, but contains a thixotropic agent. This makes it difficult for the underfill material to flow and tends to suppress void entrainment.

  Among thixotropic agents, silica particles such as long-chain polyaminoamides and acid polymer salts, unsaturated polycarboxylic acid polymers, finely divided silica, and crushed silica are preferable from the viewpoints of handleability, moldability, and voids, and retain their shape. From the viewpoint of properties, it is particularly preferable to use fine powder silica.

  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 commercially available, and as an unsaturated polycarboxylic acid polymer, for example, BYK- P105 (Bic Chemie Japan Co., Ltd. trade name) is commercially available.

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

  The fine powder silica whose surface is treated with silicone oil or a coupling agent has an average particle diameter of 12 nm, R974 (trade name of Nippon Aerosil Co., Ltd.) surface-treated with dimethylsilane, an average particle diameter of 12 nm, and trimethylsilane. Surface treated with RX200 (Nippon Aerosil Co., Ltd. trade name), average particle size of 12 nm, RY200 (Nippon Aerosil Co., Ltd. trade name) surface treated with dimethylsiloxane, average particle size of 14 nm, dimethylsiloxane surface Treated R202 (Nippon Aerosil Co., Ltd. trade name), RA200H (Nippon Aerosil Co., Ltd. trade name) having an average particle diameter of 12 nm and surface treatment with aminosilane, average particle diameter of 12 nm, and surface treatment with alkylsilane R805 (Nippon Aerosil Co., Ltd. trade name), Taira R7200 (Nippon Aerosil Co., Ltd., trade name) having a particle diameter of 12 nm and surface-treated with methacryloxysilane, YA050C-SP3 (Admatechs trade name) having an average particle diameter of 50 nm and surface-treated with phenylsilane, etc. 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 crushed silica, for example, MC3000 (trade name of Admatex Co., Ltd.) is commercially available.

  In the present invention, the “average particle size” of silica particles of finely divided silica and crushed silica is an image obtained by imaging using an electron microscope or the like, measuring the particle size of each particle, and obtaining an arithmetic average thereof. Means diameter. Examples of the method for measuring the particle diameter of the inorganic particles include 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, or the like. . 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 invention may contain a thixotropic agent alone or in combination of two or more.

  When the underfill material of the present invention contains a thixotropic agent, the content of the thixotropic agent is preferably 0.1 to 20% by mass relative to the total amount of the underfill material, 0.5 More preferably, it is 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 there exists a tendency for a moldability to improve more.

(Surfactant)
The underfill material of the present invention may contain a surfactant as necessary from the viewpoint of improving fillet properties.
The surfactant that can be used in the present invention is not particularly limited as long as it is a nonionic surfactant generally used in an underfill material used for manufacturing an electronic component device. Surfactants include polyoxyethylene alkyl ether surfactants, polyoxyalkylene alkyl ether surfactants, sorbitan fatty acid ester surfactants, polyoxyethylene sorbitan fatty acid ester surfactants, polyoxyethylene sorbitol fatty acid ester surfactants , Glycerin fatty acid ester surfactant, polyoxyethylene fatty acid ester surfactant, polyoxyethylene alkylamine surfactant, alkyl alkanolamide surfactant, polyether modified silicone surfactant, aralkyl modified silicone surfactant, polyester modified Examples include silicone surfactants and polyacrylic surfactants. Among them, polyether-modified silicone surfactants and aralkyl-modified silicone surfactants are They tend to be effective in surface tension reduction of wood.
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.

  In the underfill material of the present invention, as other additives, coloring agents 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 the present invention can be prepared by any method as long as the above various components can be dispersed and mixed. As a general method, the underfill material of the present invention can be obtained by weighing components, mixing and kneading using a roughing machine, mixing roll, planetary mixer, etc., and degassing as necessary. .

[Method of manufacturing electronic component device]
The method for manufacturing an electronic component device of the present invention (hereinafter referred to as “the manufacturing method of the present invention” as appropriate) includes a surface of the electronic component facing the wiring substrate or a surface of the wiring substrate facing the electronic component. An application step of applying the underfill material of the present invention to at least one surface of the surface, and after the application step, the electronic component and the wiring board are connected via a connecting portion, and the underfill material is cured. An electronic component device manufacturing method for manufacturing an electronic component device by electrically connecting an electronic component and a wiring board via a connecting portion.

  The manufacturing method of the present invention provides an electronic component after applying the underfill material of the present invention to at least one of the surface of the electronic component facing the wiring substrate or the surface of the wiring substrate facing the electronic component. This is a manufacturing method to which a pre-coating method for performing connection through a connecting portion between the wiring board and the wiring board and curing of the underfill material is applied. 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 the present invention is a manufacturing method of an electronic component device to which a pre-coating method is applied. By using the underfill material of the present invention having a predetermined composition in the applying step, the curing time of the underfill material can be shortened. It is possible to produce an electronic component device having excellent electrical connection reliability because it is less likely to generate voids and has excellent adhesiveness with the electronic component. The present inventors consider the reason as follows.

  That is, according to the knowledge obtained by the present inventors, the underfill material contains (A) a compound having an ethylenically unsaturated double bond, whereby the underfill in the manufacturing method of the electronic component device to which the pre-coating 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) a compound having an ethylenically unsaturated double bond is used, the underfill material tends to be inferior in adhesiveness to 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 the present invention, the underfill material (A) is a compound having an ethylenically unsaturated double bond, (A1) tricyclodecane dimethylol di (meth) acrylate or (A2) the above general formula (I-2) The (meth) acrylate compound represented by these is contained. With this configuration, in the present invention, shortening of the curing time of the underfill material, suppression of the generation of voids, and high adhesiveness with electronic components are achieved. The present inventors consider that this is because the adhesiveness of the cured product of the underfill material is improved when the underfill material contains (A1) or (A2).

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

<Granting process>
The applying step in the manufacturing method of the present invention is a step of applying an underfill material to at least one of the surface of the electronic component facing the wiring substrate or the surface of the wiring substrate facing the electronic component.

As the underfill material in the application step, there is an underfill material containing (A) a compound having an ethylenically unsaturated double bond, (B) a reaction initiator, (C) an inorganic filler, and (D) an ion trap agent. Used.
The underfill material used in the applying step is the underfill material of the present invention, 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 type of base material constituting the wiring board is not particularly limited, and does not include an organic substrate including a fiber base material such as FR-4 (Frame Regentant-4), FR-5 (Frame Regentant-5), or a fiber base material. 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 type of the conductor wiring is not particularly limited, and a conductor wiring applicable to a 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 that is not packaged with resin or the like, a semiconductor package called CSP (Chip Scale Package), 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.

  The method for applying the underfill material to the wiring board or electronic component is not particularly limited. Examples thereof include a method using a dispenser such as an air dispenser, jet dispenser, screw type dispenser, auger type dispenser, a method using casting, a method using printing such as screen printing, and the like. From the viewpoint of reducing entrainment voids when applying the underfill material, a method using a dispenser is preferable.

  The aspect at the time of providing an underfill material to a wiring board or an electronic component is not particularly limited. When applying the underfill material on the wiring board, it is applied to the entire mounting position of the electronic component, and it is applied to a cross shape composed of two lines along a rectangular diagonal corresponding to the mounting position of the electronic component. A mode in which one cross shape is added to a shape in which another cross shape is further shifted by 45 °, a mode in which the cross shape is added, and a mode in which the electronic component is mounted at a single point are exemplified. In order to suppress creep or the like of the underfill material from the viewpoint of reliability, it is preferable to provide 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 apply an 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 applied on the wiring board or electronic component can be selected according to the properties of the underfill material. The temperatures of the underfill material and the substrate surface are each preferably 25 to 150 ° C., and more preferably 25 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 ejection stability when applying the underfill material. Specifically, when the underfill material is discharged in the manufacturing method of the present invention, it is preferable to use a needle having a diameter of 0.1 to 1.0 mm, and a needle having a diameter of 0.2 to 0.5 mm is used. More preferably, it is used.

<Connection process>
The connecting step in the present invention is a step of connecting the electronic component and the wiring board through the connecting portion and curing the underfill material of the present invention after the applying step.

More specifically, the connecting step in the manufacturing method of the present invention is performed by pressurizing the electronic component and the wiring board in a state of facing each other through the connecting portion, and in the gap between the electronic component and the wiring board. A pressurizing step of filling the underfill material and bringing the electronic component and the substrate into contact with each other through the connection portion, and heat-treating the electronic component and the wiring board in contact with each other through the connection portion, It is preferable to include a heat treatment step of connecting the wiring board and the wiring board through the connection portion and curing the underfill material of the present invention.
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 an example including an application process and a heat treatment process.

<< Pressurization process >>
The pressurizing step is performed in such a manner that the electronic component and the wiring board are 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 invention, and the electronic component and In this step, the substrate is brought into contact with 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 a temperature that can maintain a viscosity sufficient to fill the gap between the electronic component and the wiring board with the underfill material. There is no particular limitation. The filling temperature is, for example, 25 to 150 ° C, preferably 40 to 125 ° C, and more preferably 50 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. Here, 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 connecting portion is about 0.01 to 100 g.

<< Heat treatment process >>
In the heat treatment process, the electronic component and the wiring board are heat-treated in a state where they are 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 invention is cured. It is a process to do.

  The method for heat treatment is not particularly limited. For example, a method of heating a contact portion between a flip chip bonder and a wiring board or an electronic component, a method using a reflow furnace, and the like can be mentioned. From the standpoint that it is difficult to cause 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.

  The heat treatment step may be 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 thermally cured from the viewpoint of securing the connection through the connection part between the electronic component and the wiring board. preferable. That is, it is preferably performed at a temperature at which a connection portion is formed between the wiring on the wiring board and the electronic component, and the underfill material is thermally cured and the connection portion can be reinforced.

  The heat treatment (heating) temperature is preferably 150 to 300 ° C, more preferably 200 to 280 ° C, and still more preferably 220 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 components 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 thermally cured. Thus, there is no particular limitation as long as the connection portion can be reinforced.

  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 the generation of voids in 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 the above heat treatment is performed, if necessary, the underfill material is sufficiently cured, and further in the range of 100 to 200 ° C. for 0.1 to 10 hours of heat treatment (after (Heat 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 the exposure process is not particularly limited as long as it can cure the 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 an embodiment of a manufacturing method of the present invention will be described with reference to the drawings.
In addition, embodiment shown below is an example of the aspect which provides the underfill material of this invention 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 by a pre-coating 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. .

  First, as shown in FIG. 1A, an underfill material 6 is applied to the surface of the wiring board 5 on which the connection pads 3 are provided (the side of the wiring board 5 facing the semiconductor chip 1). 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 of the present invention is manufactured.

[Electronic component equipment]
An electronic component device manufactured by the manufacturing method of the present invention and an electronic component device manufactured using the underfill material of the present invention include a lead frame, a wired tape carrier, a rigid and flexible wiring board, glass, and a silicon wafer. Electronic components such as active elements such as semiconductor chips, transistors, diodes, and thyristors, and passive elements such as capacitors, resistors, resistor arrays, coils, and switches are mounted on supporting members (wiring boards). Examples thereof include an electronic component device obtained by sealing with the underfill material of the present invention.

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), COF (Chip On Film), etc. The underfill material of the present invention is a flip with excellent reliability. It is suitable as an underfill material for chips.
Since the underfill material of the present invention can shorten the curing time and reduce the generation of voids, it can be suitably used for flip chip bonding applications where the pitch width of the bumps is narrow. The underfill material of the present invention is particularly suitable for bump connection in which the bump pitch width is 10 to 200 μm, for example.

  As a field of flip chip in which the underfill material of the present invention is particularly suitable, a bump material for connecting a wiring board and a semiconductor element is a flip chip semiconductor element using lead-free solder such as Sn-Ag-Cu solder, Good reliability can be maintained even for a flip chip having a lead-free solder bump connection that is physically brittle compared to 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. Unless otherwise specified, “part” and “%” are based on mass. The present invention is not limited to the present embodiment unless departing from the gist thereof.

[Examples 1-5, Comparative Examples 1-3]
(A) Compound having ethylenically unsaturated double bond (A1) Acrylic compound 1: Tricyclodecane dimethylol diacrylate (Shin-Nakamura Chemical Co., Ltd., trade name “A-DCP”)
(A2) Acrylic compound 2: Bisphenol A type ethylene oxide-modified diacrylate (Shin Nakamura Chemical Co., Ltd., trade name “ABE-300”)
Acrylic compound 3: EO, PO-modified urethane dimethacrylate (Shin Nakamura Chemical Co., Ltd., trade name “UA-13”)

(B) Reaction initiator / reaction initiator 1: Dicumyl peroxide

(C) Inorganic filler / inorganic filler: spherical silica particles having a volume average particle diameter of 0.5 μm and a maximum particle diameter of 5 μm (D) ion trapping agent / ion trapping agent 1: In the above general formula (I-1), a = 6.2, b = 2.0, c = 16.0, d = 1.0, m = 4.0, uncalcined hydrotalcite compound / ion trapping agent 2: the above general formula (I-1) ), An unsintered hydrotalcite compound / ion trapping agent 3 represented by a = 4.3, b = 2.0, c = 12.6, d = 3.0, m = 3.0: Mg _{0. 7} Al _0.3 O _1.15 calcined hydrotalcite compound / ion trapping agent 4: BiO _x (OH) _y (NO ₃ ) _z (0.9 <x <1.1, 0.6 <y <0.8, 0.2 <z <0.4) Bismuth Compound

(Other resins, curing agents, etc.)
Epoxy resin: bisphenol F type epoxy resin having an epoxy equivalent of 160 g / eq (Nippon Steel & Sumikin Chemical Co., Ltd., trade name “YDF-8170C”)
Epoxy curing agent: cyclic acid anhydride with an acid anhydride equivalent of 234 g / eq (Mitsubishi Chemical Corporation, trade name “YH306”)
Curing catalyst: 2-ethyl-4-methylimidazole

(Other various additives)
・ Flux agent: Adipic acid ・ Flexible agent 1: Diblock copolymer of polymethylmethacrylic acid and polybutylacrylic acid (Arkema Co., Ltd., trade name “Nanostrength D51N”)
・ Flexible agent 2: maleic acid-modified polybutadiene (Sakai Industrial Co., Ltd., “Ricon130MA8”)
Coupling agent: 3-methacryloxypropyltrimethoxysilane, thixotropic agent: powdered silica with a volume average particle size of 12 nm (Nippon Aerosil Co., Ltd., trade name “R-805”)

  The above components are blended in parts by mass shown in Tables 1 and 2, and after being kneaded and dispersed with a three-roller and a raking machine, vacuum degassing is performed to produce the underfill materials of Examples and Comparative Examples. did. In addition, the compounding unit in a table | surface is a mass part. The amount of the inorganic filler shown in Table 1 is the ratio (mass%) of the component (C) to the total of the components (A) to (D) in Examples 1 to 5 and Comparative Example 3, and in Comparative Examples 1 and 2 , Epoxy resin, epoxy curing agent, curing catalyst, (C), the ratio (mass%) of the component (D) to the total of the components (D). The amount of ion trapping agent is the ratio (% by mass) of (D) ion trapping agent to the total amount of underfill material.

  Each underfill material obtained in Examples and Comparative Examples was evaluated by the following tests. The evaluation results are shown in Tables 1-2.

(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 For an underfill material maintained at 25 ° C. using an E-type viscometer (cone angle 3 °), the value when the rotation speed was measured at 5 rpm was defined as viscosity (Pa · s). Measured.

(3) Adhesive force A SiN film was formed on a silicon wafer, and a test piece in which an underfill material was molded to a diameter of 3 mm and a height of 3 mm was produced on the surface, and a bond tester (DAGE, trade name “DS100”) The shear strength was applied 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) Void circuit board (size: length 14 mm, width 14 mm, thickness 0.30 mm, core layer: E-679FG (trade name of Hitachi Chemical Co., Ltd.), solder resist: AUS-308 (trade name of Taiyo Holdings Co., Ltd.) And substrate plating: Ni (5.0 μm) + Pd (0.30 μm) + Au (0.35 μm)) on the chip mounting portion, using a dispenser (needle diameter 0.3 mm), the underfill material is made into one cross shape. Further, about 3 mg was applied so that another cross shape was shifted by 45 ° and overlapped. Place a wiring board coated with an underfill material on a stage heated to 50 ° C, chip (size: 7.3 mm long, 7.3 mm wide, 0.15 mm thick, bump: copper (height 30 μm), solder (material) : SnAg, height: 15 μm) and bump pitch: 80 μm, number of bumps: 328), thermocompression bonding was performed under the conditions of weight: 7.5 N, temperature / time: 260 ° C./5 seconds, and then 165 ° C. The semiconductor device was obtained by curing the underfill material under the conditions of 30 minutes.

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”). The four grades of evaluation criteria were divided into voids.
-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) 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 three times through a reflow furnace of a far infrared heating system (preheating at 150 ° C. to 180 ° C. for 50 seconds, peak temperature: 260 ° C., heating time of 250 ° C. or higher for 40 seconds), 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 defined as reflow resistance.
(6) Bias-HAST resistance A semiconductor by applying an underfill agent on a comb-shaped electrode substrate (L / S = 40 μm / 40 μm) having copper wiring and curing the underfill material at 165 ° C. for 30 minutes. Got the device. The test was carried out for 100 hours by setting it under conditions of 130 ° C. and 85% RH with a voltage of 7V being applied. A case where an insulation resistance of 10 ⁵ Ω or more was maintained was regarded as a non-defective product, and (number of defective packages) / (number of evaluated packages) was defined as Bias-HAST resistance.

  In each of Examples 1 to 5, an underfill material containing (A) a compound having an ethylenically unsaturated double bond, (B) a reaction initiator, (C) an inorganic filler, and (D) an ion trapping agent. I use it.

The following can be seen from the evaluation results shown in Tables 3-4.
Examples 1 to 5 contain components (A) to (D), and Comparative Examples 1 and 3 are formulations that do not contain the component (D) of Examples 1 to 5. And the comparative examples 1 and 2 are the mixing | blending which used the epoxy resin composition as an underfill material.
When the acrylic compositions of Examples 1 to 5 and the epoxy compositions of Comparative Examples 1 and 2 were compared, the epoxy composition had a longer gelation time of 8 seconds than 2 seconds of the acrylic composition, and the viscosity. However, it is as high as 48 to 55 Pa · s with respect to 12 to 23 Pa · s seconds of the acrylic composition. The adhesive force is as high as 15 MPa with respect to 8 to 12 MPa of the acrylic composition. Epoxy compositions have high adhesive strength but are very inferior in voids and reflow resistance.
On the other hand, an acrylic composition has a short gelling time, a low viscosity, and excellent reflow resistance and void resistance, although it cannot be achieved with an adhesive force, as compared with an epoxy composition. In addition, since the gelation time is short, the mounting time can be shortened and the productivity can be improved.
The acrylic composition can enhance the adhesive force by containing an unfired hydrotalcite compound as in Examples 1 to 3.
The reason why the adhesive strength is improved when the unfired hydrotalcite compound is contained is unknown, but the electrical connection between the electronic component and the wiring board is prevented from being impaired, and the connection reliability of the electronic component device is further improved. can do.
(D) Bias-HAST resistance is improved in Examples 1 to 5 and Comparative Example 2 containing an ion trapping agent compared to Comparative Examples 1 and 3 not containing the ion trapping agent. This is presumably because the inclusion of the ion trapping agent reduces the amount of ion impurities in the cured product and improves the insulation reliability.

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

Claims (15)

An applying step of applying an underfill material to at least one of the surface of the electronic component facing the wiring substrate or the surface of the wiring substrate facing the electronic component, and after the applying step, the electron An electronic component device by electrically connecting an electronic component and a wiring board including a connecting step of connecting the component and the wiring board via a connecting portion and curing the underfill material. Is an underfill material used in a method for manufacturing an electronic component device.
The underfill material contains (A) a compound having an ethylenically unsaturated double bond, (B) a reaction initiator, (C) an inorganic filler, and (D) an ion trap agent.   The underfill material according to claim 1, wherein the (D) ion trapping agent is a hydrotalcite compound. The underfill material according to claim 1 or 2, wherein the (D) ion trapping agent is an unfired hydrotalcite compound represented by the following general formula (I-1).

(A, b, c, d, m are each integers of 0 or more)   The underfill material according to any one of claims 1 to 3, wherein the content of the (D) ion trapping agent is 0.1% by mass or more based on the total amount of the underfill material.   The underfill according to any one of claims 1 to 4, wherein the compound (A) having an ethylenically unsaturated double bond includes a compound having two or more ethylenically unsaturated double bonds in one molecule. Wood.   The content of the compound containing 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. 5. The underfill material according to 5.   The underfill material according to any one of claims 1 to 6, wherein the compound (A) having an ethylenically unsaturated double bond contains (A1) tricyclodecane dimethylol di (meth) acrylate.   The content of the (A1) 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. Underfill material. The compound (A) having an ethylenically unsaturated double bond includes (A2) a (meth) acrylate compound represented by the following general formula (I-2). Underfill material.

(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 each p independently represents an integer of 0 to 50, and q independently represents an integer of 0 to 50.)   (A2) 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 underfill material according to claim 9.   The underfill material according to claim 1, wherein the (B) reaction initiator contains an organic peroxide.   The underfill material according to any one of claims 1 to 11, wherein the (C) inorganic filler has a volume average particle diameter of 0.1 to 10 µm.   The content rate of said (C) inorganic filler is 10 mass% or more with respect to the whole quantity of an underfill material, The underfill material of any one of Claims 1-12. The underfill material according to any one of claims 1 to 13 is applied to at least one of the surface of the electronic component facing the wiring substrate or the surface of the wiring substrate facing the electronic component. An applying step to
A method of 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 underfill material after the applying step.   The electronic component apparatus manufactured using the underfill material of any one of Claims 1-13.

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