JP6930555B2 - Protective material for electronic circuits, encapsulant for protective material for electronic circuits, encapsulation method and manufacturing method of semiconductor devices - Google Patents

Description

The present invention relates to a protective material for an electronic circuit, a sealing material for a protective material for an electronic circuit, a sealing method, and a method for manufacturing a semiconductor device.

As a structure in which a semiconductor chip and a substrate are electrically connected, there is a structure called a wire bonding structure in which a semiconductor element and a substrate are connected via a wire. In the wire bonding structure, a semiconductor device is formed by sealing a semiconductor chip, a substrate, and a wire electrically connecting them with a resin composition. At that time, there is a problem that pressure is applied to the wire due to the flow of the resin composition, misalignment of the wire (wire flow) occurs, and the semiconductor chip is not sufficiently protected.

The resin composition used for encapsulating a semiconductor package usually contains an inorganic filler, but the fluidity of the resin composition generally improves when the amount of the inorganic filler is reduced. Therefore, Patent Document 1 has a two-layer structure consisting of an inner layer and an outer layer, and the amount of the inorganic filler of the resin composition forming the inner layer in contact with the wire is set to 5% by mass to 40% by mass to increase the fluidity. A sealing structure is described in which the amount of the inorganic filler of the resin composition forming the outer layer is increased to 60% by mass to 95% by mass as compared with the inner layer while suppressing the wire flow.

Japanese Unexamined Patent Publication No. 2011-35334

In the sealing structure described in Patent Document 1, two types of resin compositions having different amounts of inorganic fillers are used properly for the inner layer and the outer layer to try to eliminate the trade-off relationship between wire flow suppression and heat dissipation improvement. ing. However, in a field where a semiconductor device is particularly required to have high heat dissipation, it is desirable that not only the outer layer of the sealed structure but also the inner layer has excellent heat dissipation. Further, in the sealing structure described in Patent Document 1, the amount of the inorganic filler in the inner layer is small, and there is a possibility that sufficient strength for protecting the semiconductor chip cannot be obtained.

The present invention has been made in view of the above circumstances, and is an electronic circuit protection material capable of forming a sealing structure having excellent heat dissipation and electronic circuit protection performance, and a sealing for an electronic circuit protection material used together with this electronic circuit protection material. It is an object of the present invention to provide a material, a sealing method using a combination of these electronic circuit protective materials and a sealing material for an electronic circuit protective material, and a method for manufacturing a semiconductor device having excellent heat dissipation and electronic circuit protection performance.

Means for solving the above problems include the following embodiments.
<1> An electronic circuit protective material containing a resin component and an inorganic filler, and the content of the inorganic filler is 50% by mass or more of the whole.
<2> The electronic circuit protective material according to <1>, wherein the resin component is a thermosetting resin component.
<3> The electronic circuit protective material according to <1> or <2>, wherein the amount of chlorine ions is 100 ppm or less.
<4> The electronic circuit protective material according to any one of <1> to <3>, wherein the maximum particle size of the inorganic filler is 75 μm or less.
<5> The electronic circuit protective material according to any one of <1> to <4>, wherein the viscosity measured at 75 ° C. and a shear rate of 5s- ^{1 is 3.0 Pa · s or less.}
<6> The electronic circuit protective material according to any one of <1> to <5>, wherein the viscosity measured at 25 ° C. and a shear rate of 10s- ^{1 is 30 Pa · s or less.}
<7> When the viscosity measured under the conditions of 75 ° C. and a shear rate of 5s ^-1 is the viscosity A, and the viscosity measured under the conditions of 75 ° C. and a shear rate of 50s ^-1 is the viscosity B, the viscosity A / viscosity B. The electronic circuit protective material according to any one of <1> to <6>, wherein the fluctuation index at 75 ° C. obtained as the value of is 0.1 to 2.5.
<8> The electronic circuit protective material according to any one of <1> to <7>, wherein the resin component contains an epoxy resin.
<9> The electronic circuit protective material according to any one of <1> to <8>, which comprises an epoxy resin in which the resin component has an aromatic ring and an aliphatic epoxy resin.
<10> The resin component is at least one selected from the group consisting of a liquid bisphenol type epoxy resin and a liquid glycidylamine type epoxy resin as the epoxy resin having an aromatic ring, and linear as the aliphatic epoxy resin. The electronic circuit protective material according to any one of <1> to <9>, which comprises an aliphatic epoxy resin.
<11> A sealing material for an electronic circuit protective material for sealing around a cured product of the electronic circuit protective material according to any one of <1> to <10>.
<12> The electronic circuit protective material according to any one of <1> to <10> and the electronic circuit protective material encapsulant according to <11> are combined to seal the periphery of the electronic circuit. , Sealing method.
<13> A method for manufacturing a semiconductor device, comprising a step of applying the electronic circuit protective material according to any one of <1> to <10> around the electronic circuit to form a cured product of the electronic circuit protective material. ..
<14> The method for manufacturing a semiconductor device according to <13>, further comprising a step of sealing the periphery of the cured product of the electronic circuit protective material with a sealing resin composition.
<15> The method for manufacturing a semiconductor device according to <13> or <14>, wherein the electronic circuit is a wire connecting a semiconductor chip and a substrate.

According to the present invention, an electronic circuit protection material capable of forming a sealing structure having excellent heat dissipation and protection performance of an electronic circuit, a sealing material for an electronic circuit protection material used together with the electronic circuit protection material, and protection of these electronic circuits. Provided are a sealing method in which a material and a sealing material for an electronic circuit protective material are used in combination, and a method for manufacturing a semiconductor device having excellent heat dissipation and electronic circuit protection performance.

It is a figure explaining the evaluation method of the fluidity of an electronic circuit protection material.

Hereinafter, embodiments for carrying out the present invention will be described in detail. However, the present invention is not limited to the following embodiments. In the following embodiments, the components (including element steps and the like) are not essential unless otherwise specified. The same applies to the numerical values and their ranges, and does not limit the present invention.

In the present disclosure, the term "process" includes not only a process independent of other processes but also the process if the purpose of the process is achieved even if the process cannot be clearly distinguished from the other process. ..
The numerical range indicated by using "~" in the present disclosure includes the numerical values before and after "~" as the minimum value and the maximum value, respectively.
In the numerical range described stepwise in the present disclosure, the upper limit value or the lower limit value described in one numerical range may be replaced with the upper limit value or the lower limit value of another numerical range described stepwise. .. Further, in the numerical range described in the present disclosure, the upper limit value or the lower limit value of the numerical range may be replaced with the value shown in the examples.
In the present disclosure, each component may contain a plurality of applicable substances. When a plurality of substances corresponding to each component are present in the composition, the content or content of each component is the total content or content of the plurality of substances present in the composition unless otherwise specified. Means quantity.
In the present disclosure, a plurality of types of particles corresponding to each component may be contained. When a plurality of particles corresponding to each component are present in the composition, the particle size of each component means a value for a mixture of the plurality of particles present in the composition unless otherwise specified.
In the present disclosure, the term "layer" or "membrane" is used only in a part of the region in addition to the case where the layer or the membrane is formed in the entire region when the region in which the layer or the membrane is present is observed. The case where it is formed is also included.
In the present disclosure, the term "laminated" refers to stacking layers, and two or more layers may be bonded or the two or more layers may be removable.

<Electronic circuit protection material>
The electronic circuit protective material of the present embodiment contains a resin component and an inorganic filler, and the content of the inorganic filler is 50% by mass or more of the whole. The electronic circuit protective material may contain a component other than the resin component and the inorganic filler, if necessary.

In the present disclosure, the "electronic circuit protective material" means a material for protecting the periphery of an electronic circuit in a semiconductor device, and for sealing the periphery of a wire connecting a semiconductor chip and a substrate in a wire bonding structure. Examples thereof include a resin material (wire coating material) used, a resin material (underfill material) that fills the space between the semiconductor chip and the substrate, and the like. By protecting the periphery of the electronic circuit with an electronic circuit protective material, it is possible to avoid problems such as wire flow caused by the sealing material when the outside thereof is further sealed with the sealing material. Further, it is not necessary to consider the possibility that the sealing material causes a problem such as wire flow, and the degree of freedom in selecting the sealing material can be expanded.

Electronic circuit protective materials with an inorganic filler content of 40% by mass or less have a low content of the inorganic filler in order to increase fluidity, while the heat dissipation and strength near the electronic circuit are high. It is considered to be decreasing. The electronic circuit protective material of the present embodiment can form a sealing structure having better heat dissipation and strength than the conventional one by setting the content of the inorganic filler to 50% by mass or more of the whole.

The viscosity of the electronic circuit protective material measured at 75 ° C. and a shear rate of 5s- ¹ is preferably 3.0 Pa · s or less, and more preferably 2.0 Pa · s or less. When the viscosity of the electronic circuit protective material at 75 ° C. and a shear rate of 5s ^-1 is 3.0 Pa · s or less, the occurrence of wire flow is effectively suppressed when the electronic circuit protective material is applied around the wire. It tends to be done. The lower limit of the viscosity is not particularly limited, but it is preferably 0.01 Pa · s or more from the viewpoint of maintaining the state of being applied around the wire.

The viscosity of the electronic circuit protective material measured at 25 ° C. and a shear rate of 10 s- ¹ is preferably 30 Pa · s or less, and more preferably 20 Pa · s or less. The lower limit of the viscosity is not particularly limited, but it is preferably 0.1 Pa · s or more from the viewpoint of maintaining the state of being applied around the wire.

In the present disclosure, the viscosity of the electronic circuit protective material at 25 ° C. is a value measured using an E-type viscometer, and the viscosity at 75 ° C. is a rheometer (for example, the trade name "AR2000" of TA Instruments). ) Is the value measured using.

The fluctuation index of the electronic circuit protective material can be set according to the application (for example, whether it is used as a wire coating material or an underfill material), the state of the electronic circuit and the semiconductor device, and the like. For example, the fluctuation index at 75 ° C. is preferably 0.1 to 2.5.

For the fluctuation index of the electronic circuit protective material at 75 ° C., the ^{viscosity measured under the conditions of 75 ° C. and a shear rate of 5s -1} is defined as the viscosity A, and the viscosity measured under the conditions of 75 ° C. and a shear rate of 50s ^-1 is defined as the viscosity. When the viscosity is B, it is obtained as a value of viscosity A / viscosity B.

The method for ensuring that the electronic circuit protective material satisfies the above-mentioned viscosity condition is not particularly limited. For example, as a method for lowering the viscosity of the electronic circuit protective material, a method using a low-viscosity resin component, a method of adding a solvent, and the like can be mentioned, and these can be used alone or in combination.

[Resin component]
The resin component contained in the electronic circuit protective material is not particularly limited as long as the electronic circuit protective material can satisfy the above conditions. From the viewpoint of compatibility with existing equipment, stability of characteristics as an electronic circuit protective material, etc., it is preferable to use a thermosetting resin component, and it is more preferable to use an epoxy resin. Further, it is preferable to use a resin component that is liquid at room temperature (25 ° C.) (hereinafter, also simply referred to as “liquid”), and it is more preferable to use a liquid epoxy resin. The resin component may be a combination of an epoxy resin and a curing agent.

(Epoxy resin)
Examples of the epoxy resin that can be used as the electronic circuit protection material include diglycidyl ether type epoxy resins such as bisphenol A, bisphenol F, bisphenol AD, bisphenol S, and hydrogenated bisphenol A, and phenols typified by orthocresol novolac type epoxy resins. Epoxy of novolak resin of similar and aldehydes (novolak type epoxy resin), glycidyl ester type epoxy resin obtained by reaction of polybasic acid such as phthalic acid and dimer acid with epichlorohydrin, p-aminophenol, diaminodiphenylmethane, Examples thereof include a glycidylamine type epoxy resin obtained by reacting an amine compound such as isocyanuric acid with epichlorohydrin, a linear aliphatic epoxy resin obtained by oxidizing an olefin bond with a peracid such as peracetic acid, and an alicyclic epoxy resin. .. The epoxy resin may be used alone or in combination of two or more.

Among the above epoxy resins, at least one selected from the group consisting of diglycidyl ether type epoxy resin and glycidyl amine type epoxy resin is preferable from the viewpoint of viscosity, usage record, material price and the like. Of these, a liquid bisphenol type epoxy resin is preferable from the viewpoint of fluidity, and a liquid glycidylamine type epoxy resin is preferable from the viewpoint of heat resistance, adhesiveness and fluidity.

In some embodiments of the electronic circuit protective material, an epoxy resin having an aromatic ring and an aliphatic epoxy resin are used as resin components. For example, a liquid bisphenol F type epoxy resin and a liquid glycidylamine type epoxy resin as an epoxy resin having an aromatic ring, and a linear aliphatic epoxy resin as an aliphatic epoxy resin are used as resin components.

Examples of the glycidylamine type epoxy resin include p- (2,3-epoxypropoxy) -N, N-bis (2,3-epoxypropyl) aniline, diglycidylaniline, diglycidyltoluidine, diglycidylmethoxyaniline, and diglycidyldimethyl. Examples thereof include aniline and diglycidyl trifluoromethylaniline.
Examples of the linear aliphatic epoxy resin include 1,6-hexanediol diglycidyl ether, resorcinol diglycidyl ether, propylene glycol diglycidyl ether, 1,3-bis (3-glycidoxypropyl) tetramemethyldisiloxane, and cyclohexane. Examples thereof include dimethanol diglycidyl ether.

When a liquid bisphenol F type epoxy resin, a liquid glycidylamine type epoxy resin, and a linear aliphatic epoxy resin are used in combination as the epoxy resin, the blending ratio thereof is not particularly limited, but for example, the liquid glycidylamine type. The compounding ratio may be such that the epoxy resin is 40% by mass to 70% by mass of the whole, and the total of the liquid bisphenol F type epoxy resin and the linear aliphatic epoxy resin is 30% by mass to 60% by mass of the whole. ..

The content of the epoxy resin exemplified above in the entire epoxy resin (the total when two or more kinds of the exemplified epoxy resins are used) is preferably 20% by mass or more from the viewpoint of fully exhibiting the performance. It is more preferably 30% by mass or more, and further preferably 50% by mass or more. The upper limit of the content is not particularly limited, and can be determined within a range in which the desired properties and characteristics of the electronic circuit protective material can be obtained.

As the epoxy resin, it is preferable to use a liquid epoxy resin, but a solid epoxy resin at room temperature (25 ° C.) may be used in combination. When a solid epoxy resin at room temperature is used in combination, the ratio is preferably 20% by mass or less of the total epoxy resin.

From the viewpoint of suppressing wire corrosion, it is preferable that the amount of chlorine ions in the electronic circuit protective material is small. Specifically, for example, it is preferably 100 ppm or less.
In the present disclosure, the amount of chloride ions of the electronic circuit protective material is a value (ppm) obtained by treating with ion chromatography under the conditions of 121 ° C. and 20 hr and converting at 2.5 g / 50 cc.

(Hardener)
As the curing agent, those generally used as a curing agent for epoxy resins such as amine-based curing agents, phenol curing agents, and acid anhydrides can be used without particular limitation. From the viewpoint of suppressing wire flow, it is preferable to use a liquid curing agent. From the viewpoint of excellent temperature cycle resistance, moisture resistance, and the like, and the reliability of the semiconductor package can be improved, the curing agent is preferably an aromatic amine compound, and more preferably a liquid aromatic amine compound. As the curing agent, one type may be used alone or two or more types may be used in combination.

Examples of the liquid aromatic amine compound include diethyltoluenediamine, 1-methyl-3,5-diethyl-2,4-diaminobenzene, 1-methyl-3,5-diethyl-2,6-diaminobenzene, 1,3. , 5-Triethyl-2,6-diaminobenzene, 3,3'-diethyl-4,4'-diaminodiphenylmethane, 3,5,3', 5'-tetramethyl-4,4'-diaminodiphenylmethane, dimethylthio Toluenediamine and the like can be mentioned.

The liquid aromatic amine compound is also available as a commercial product. For example, jER Cure W (Mitsubishi Chemical Co., Ltd., product name), Kayahard AA, Kayahard AB, Kayahard AS (Nippon Kayaku Co., Ltd., product name), Totoamine HM-205 (Nippon Steel & Sumitomo Metal Chemical Co., Ltd.) Company, product name), Adeka Hardener EH-101 (Adeka Corporation, product name), Epomic Q-640, Epomic Q-643 (Mitsui Chemical Co., Ltd., product name), DETDA80 (Lonza, product name), etc. It is possible.

Among the liquid aromatic amine compounds, 3,3'-diethyl-4,4'-diaminodiphenylmethane, diethyltoluenediamine and dimethylthiotoluenediamine are preferable from the viewpoint of storage stability of the electronic circuit protective material, and the curing agent is It is preferable that any one of these or a mixture thereof is the main component. Examples of diethyltoluenediamine include 3,5-diethyltoluene-2,4-diamine and 3,5-diethyltoluene-2,6-diamine, which may be used alone or in combination. The ratio of 3,5-diethyltoluene-2,4-diamine is preferably 60% by mass or more of the total diethyltoluenediamine.

The amount of the curing agent in the electronic circuit protective material is not particularly limited, and can be selected in consideration of the equivalent ratio with the epoxy resin and the like. From the viewpoint of suppressing the unreacted content of the epoxy resin or the curing agent, the amount of the curing agent is the equivalent number of the functional groups of the curing agent to the equivalent number of the epoxy groups of the epoxy resin (for example, in the case of an amine-based curing agent, the activity is active. The ratio of the equivalent number of hydrogen) is preferably in the range of 0.7 to 1.6, more preferably in the range of 0.8 to 1.4, and more preferably 0.9 to 1. It is more preferable that the amount is in the range of .2.

[Inorganic filler]
The type of the inorganic filler contained in the electronic circuit protective material is not particularly limited. For example, powders of silica, calcium carbonate, clay, alumina, silicon nitride, silicon carbide, boron nitride, calcium silicate, potassium titanate, aluminum nitride, beryllia, zirconia, zircon, fosterite, steatite, spinel, mullite, titania and the like. Examples thereof include a body, beads obtained by spheroidizing these, glass fibers, and the like. Further, an inorganic filler having a flame-retardant effect may be used, and examples of such an inorganic filler include aluminum hydroxide, magnesium hydroxide, zinc borate, zinc molybdate and the like. As the inorganic filler, one type may be used alone or two or more types may be used in combination.

Among the inorganic fillers, silica is preferable from the viewpoint of availability, chemical stability, and material cost. Examples of silica include spherical silica and crystalline silica, and spherical silica is preferable from the viewpoint of fluidity and permeability into fine gaps of the electronic circuit protective material. Examples of spherical silica include silica obtained by an explosive combustion method, molten silica, and the like.

The surface of the inorganic filler may be surface-treated. For example, the surface may be treated with a coupling agent described later.

The volume average particle size of the inorganic filler is preferably 0.1 μm to 30 μm, more preferably 0.3 μm to 5 μm, and even more preferably 0.5 μm to 3 μm. In particular, in the case of spherical silica, the volume average particle size is preferably within the above range. When the volume average particle size is 0.1 μm or more, the dispersibility in the electronic circuit protective material tends to be excellent, and the fluidity tends to be excellent. When the volume average particle diameter is 30 μm or less, the sedimentation of the inorganic filler in the electronic circuit protective material is reduced, the permeability and fluidity of the electronic circuit protective material into the fine gaps are improved, and voids and unfilled materials are not filled. Occurrence tends to be suppressed.

In the present disclosure, the volume average particle size of the inorganic filler is the particle size (D50%) when the accumulation from the small diameter side is 50% in the volume-based particle size distribution obtained by using the laser diffraction type particle size distribution measuring device. means.

The maximum particle size of the inorganic filler is preferably 75 μm or less, more preferably 50 μm or less, and further preferably 20 μm or less.

In the present disclosure, the maximum particle size of the inorganic filler means the particle size (D99%) when the accumulation from the small diameter side is 99% in the volume-based particle size distribution.

The blending amount of the inorganic filler is not particularly limited as long as it is 50% by mass of the entire electronic circuit protective material. From the viewpoint of sufficiently obtaining the effect of blending the inorganic filler, the blending amount of the inorganic filler may be 60% by mass or more of the entire electronic circuit protective material, or 70% by mass or more. ..
From the viewpoint of suppressing an increase in the viscosity of the electronic circuit protective material, the blending amount of the inorganic filler is preferably 80% by mass or less of the entire electronic circuit protective material.

[solvent]
The electronic circuit protective material may contain a solvent. By including the solvent, the viscosity of the electronic circuit protective material can be adjusted within a desired range. As the solvent, one type may be used alone, or two or more types may be used in combination.

The type of solvent is not particularly limited, and can be selected from those generally used for resin compositions used in semiconductor device mounting technology. Specifically, alcohol solvents such as butyl carbitol acetate, methyl alcohol, ethyl alcohol, propyl alcohol and butyl alcohol, ketone solvents such as acetone and methyl ethyl ketone, ethylene glycol ethyl ether, ethylene glycol methyl ether and ethylene glycol butyl ether, Glycol ether solvents such as propylene glycol methyl ether, dipropylene glycol methyl ether, propylene glycol ethyl ether and propylene glycol methyl ether acetate, lactone solvents such as γ-butyrolactone, δ-valerolactone and ε-caprolactone, dimethylacetamide and dimethyl Examples thereof include amide solvents such as formamide and aromatic solvents such as toluene and xylene.
From the viewpoint of avoiding the formation of bubbles due to rapid volatilization when curing the electronic circuit protective material for electronic circuits, it is preferable to use a solvent having a high boiling point (for example, the boiling point at normal pressure is 170 ° C. or higher).

When the electronic circuit protective material contains a solvent, the amount thereof is not particularly limited, but is preferably 1% by mass to 70% by mass of the entire electronic circuit protective material.

[Curing accelerator]
The electronic circuit protective material may contain a curing accelerator that accelerates the reaction between the epoxy resin and the curing agent, if necessary.
The curing accelerator is not particularly limited, and conventionally known ones can be used. For example, 1,8-diaza-bicyclo (5,4,0) undecene-7, 1,5-diaza-bicyclo (4,5,3,0) nonen, 5,6-dibutylamino-1,8-diaza-bicyclo. (5,4,5) Cycloamidine compounds such as undecene-7, tertiary amine compounds such as triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, tris (dimethylaminomethyl) phenol, and 2-methylimidazole. , 2-Ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-phenylimidazole, 1-benzyl-2-methylimidazole, 2-phenyl-4,5-dihydroxymethyl Imidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2,4-diamino-6- (2'-methylimidazolyl- (1'))-ethyl-s-triazine, 2-heptadecylimidazole, etc. Organic phosphine compounds such as imidazole compounds, trialkylphosphine (tributylphosphine, etc.), dialkylarylphosphine (dimethylphenylphosphine, etc.), alkyldiarylphosphine (methyldiphenylphosphine, etc.), triphenylphosphine, alkyl group-substituted triphenylphosphine, and these. Malein anhydride, 1,4-benzoquinone, 2,5-turquinone, 1,4-naphthoquinone, 2,3-dimethylbenzoquinone, 2,6-dimethylbenzoquinone, 2,3-dimethoxy-5-methyl A molecule formed by adding a quinone compound such as -1,4-benzoquinone, 2,3-dimethoxy-1,4-benzoquinone, phenyl-1,4-benzoquinone, or a compound having a π bond such as diazophenylmethane or phenol resin. Examples include compounds having internal polarization and derivatives thereof. Further, phenylboron salts such as 2-ethyl-4-methylimidazole tetraphenylborate and N-methylmorpholine tetraphenylborate can be mentioned. Further, as a curing accelerator having potential, core-shell particles formed by coating a shell of an epoxy compound which is a solid at room temperature with a compound having an amino group which is solid at room temperature as a core can be mentioned. The curing accelerator may be used alone or in combination of two or more.

When the electronic circuit protective material contains a curing accelerator, the amount thereof is not particularly limited, but is preferably 0.1 part by mass to 40 parts by mass with respect to 100 parts by mass of the epoxy resin, and 1 part by mass to 20 parts by mass. Is more preferable.

[Flexible agent]
The electronic circuit protective material may contain a flexible agent, if necessary, from the viewpoint of improving heat resistance and impact resistance, reducing stress on the semiconductor element, and the like.
The flexible agent is not particularly limited and can be selected from those generally used for resin compositions. Of these, rubber particles are preferable. Examples of the rubber particles include particles such as styrene-butadiene rubber (SBR), nitrile-butadiene rubber (NBR), butadiene rubber (BR), urethane rubber (UR), and acrylic rubber (AR). Among these, acrylic rubber particles are preferable from the viewpoint of heat resistance and moisture resistance, and acrylic polymer particles having a core-shell structure (that is, core-shell type acrylic rubber particles) are more preferable.

Further, silicone rubber particles can also be preferably used. Examples of the silicone rubber particles include silicone rubber particles cross-linked with polyorganosiloxane such as linear polydimethylsiloxane, polymethylphenylsiloxane, and polydiphenylsiloxane, silicone rubber particles whose surface is coated with silicone resin, and emulsified polymerization. Examples thereof include core-shell polymer particles composed of a core of solid silicone particles obtained in 1 and a shell of an organic polymer such as an acrylic resin. The shape of these silicone rubber particles may be amorphous or spherical, but spherical ones are preferable in order to keep the viscosity of the electronic circuit protective material low. Commercially available products of these silicone rubber particles are available from, for example, Toray Dow Corning Silicone Co., Ltd., Shin-Etsu Chemical Co., Ltd., and the like.

(Coupling agent)
As the electronic circuit protective material, a coupling agent may be used for the purpose of enhancing the adhesiveness between the resin component and the inorganic filler or the interface between the resin component and the wire. The coupling agent may be used for the surface treatment of the inorganic filler, or may be blended separately from the inorganic filler.

The coupling agent is not particularly limited, and known ones can be used. For example, silane compounds having an amino group (primary, secondary or tertiary), various silane compounds such as epoxysilane, mercaptosilane, alkylsilane, ureidosilane, vinylsilane, titanium compounds, aluminum chelate compounds, and aluminum / zirconium compounds. And so on. As the coupling agent, one type may be used alone or two or more types may be used in combination.

Specifically, as the silane coupling agent, vinyl trichlorosilane, vinyl triethoxysilane, vinyl tris (β-methoxyethoxy) silane, γ-methacryloxypropyl trimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxy Silane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, vinyltriacetoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropylmethyldimethoxysilane , Γ-Aminopropyltriethoxysilane, γ-aminopropylmethyldiethoxysilane, γ-anilinopropyltrimethoxysilane, γ-anilinopropyltriethoxysilane, γ- (N, N-dimethyl) aminopropyltrimethoxysilane , Γ- (N, N-diethyl) aminopropyltrimethoxysilane, γ- (N, N-dibutyl) aminopropyltrimethoxysilane, γ- (N-methyl) anilinopropyltrimethoxysilane, γ- (N-) Ethyl) anilinopropyltrimethoxysilane, γ- (N, N-dimethyl) aminopropyltriethoxysilane, γ- (N, N-diethyl) aminopropyltriethoxysilane, γ- (N, N-dibutyl) aminopropyl Triethoxysilane, γ- (N-methyl) anilinopropyltriethoxysilane, γ- (N-ethyl) anilinopropyltriethoxysilane, γ- (N, N-dimethyl) aminopropylmethyldimethoxysilane, γ-( N, N-diethyl) aminopropylmethyldimethoxysilane, γ- (N, N-dibutyl) aminopropylmethyldimethoxysilane, γ- (N-methyl) anilinopropylmethyldimethoxysilane, γ- (N-ethyl) anilino Propylmethyldimethoxysilane, N- (trimethoxysilylpropyl) ethylenediamine, N- (dimethoxymethylsilylisopropyl) ethylenediamine, methyltrimethoxysilane, dimethyldimethoxysilane, methyltriethoxysilane, γ-chloropropyltrimethoxysilane, hexamethyldisilane , Vinyl trimethoxysilane, γ-mercaptopropylmethyldimethoxysilane and the like.

Specific examples of the titanium coupling agent include isopropyltriisostearoyl titanate, isopropyltris (dioctylpyrophosphate) titanate, isopropyltri (N-aminoethyl-aminoethyl) titanate, tetraoctylbis (ditridecylphosphite) titanate, and tetra. (2,2-diallyloxymethyl-1-butyl) bis (ditridecyl) phosphite titanate, bis (dioctylpyrophosphate) oxyacetate titanate, bis (dioctylpyrophosphate) ethylene titanate, isopropyltrioctanoyl titanate, isopropyldimethacryliso Examples thereof include stearoyl titanate, isopropyltridodecylbenzenesulfonyl titanate, isopropylisostearoyl dialicyl titanate, isopropyltri (dioctyl phosphate) titanate, isopropyltricylphenyl titanate, tetraisopropylbis (dioctyl phosphate) titanate and the like.

When the electronic circuit protective material contains a coupling agent, the amount thereof is not particularly limited, but is preferably 1 part by mass to 30 parts by mass with respect to 100 parts by mass of the inorganic filler.

[Ion trap agent]
The electronic circuit protective material may contain an ion trap agent from the viewpoint of improving migration resistance, moisture resistance, high temperature standing characteristics, and the like of the semiconductor package. As the ion trap agent, one type may be used alone or two or more types may be used in combination.

Examples of the ion trapping agent include anion exchangers represented by the following composition formulas (V) and (VI).
Mg _1-x Al _x (OH) ₂ (CO ₃ ) _{x / 2}・ mH ₂ O ・ ・ ・ (V)
(0 <X ≤ 0.5, m is a positive number)
BiO _x (OH) _y (NO ₃ ) ₂ ... (VI)
(0.9 ≦ x ≦ 1.1, 0.6 ≦ y ≦ 0.8, 0.2 ≦ z ≦ 0.4)

The compound of the above formula (V) is available as a commercially available product (Kyowa Chemical Industry Co., Ltd., trade name "DHT-4A"). Further, the compound of the above formula (VI) is available as a commercially available product (Toagosei Co., Ltd., trade name "IXE500"). Anion exchangers other than the above compounds can also be used as ion trapping agents. For example, hydrous oxides of elements selected from magnesium, aluminum, titanium, zirconium, antimony and the like can be mentioned.

When the electronic circuit protective material contains an ion trap agent, the amount thereof is not particularly limited. For example, it is preferably 0.1% by mass to 3.0% by mass, and more preferably 0.3% by mass to 1.5% by mass of the entire electronic circuit protective material.

When the ion trap agent is in the form of particles, its volume average particle diameter (D50%) is preferably 0.1 μm to 3.0 μm. The maximum particle size is preferably 10 μm or less.

[Other ingredients]
The electronic circuit protective material may contain a component other than the above-mentioned components, if necessary. For example, a dye, a colorant such as carbon black, a diluent, a leveling agent, an antifoaming agent, and the like can be blended as needed.

[Manufacturing method of electronic circuit protection material]
The method for producing the electronic circuit protective material is not particularly limited as long as each component of the electronic circuit protective material can be sufficiently dispersed and mixed. For example, as a general method, a predetermined blending amount of a component can be mixed and kneaded using a raker, a mixing roll, a planetary mixer, or the like, and defoamed if necessary.

[How to use electronic circuit protection material]
The electronic circuit protection material can be used in any wire bonding type mounting technique. Specifically, for example, an electronic circuit protective material is applied around the wire that electrically connects the semiconductor element and the substrate, and the wire is cured to seal the wire and the position of the wire so that the wire does not flow. To fix. The electronic circuit protective material may be applied to at least the periphery of the wire, and may be applied to the entire surface of the substrate or only a part of the substrate. The method of applying the electronic circuit protective material around the wire is not particularly limited, and a dispensing method, a casting method, a printing method, or the like can be adopted.

<Encapsulant for electronic circuit protection material>
The sealing material for the electronic circuit protective material of the present embodiment is for sealing the periphery of the cured product of the electronic circuit protective material described above.

The sealing material for an electronic circuit protective material does not directly seal the periphery of the electronic circuit, but seals the periphery of the cured product of the electronic circuit protective material formed around the electronic circuit. Therefore, it is not necessary to consider the occurrence of problems such as wire flow due to the flow of the sealing material for the electronic circuit protective material. Therefore, the type of the sealing material for the electronic circuit protective material is not particularly limited, and those generally used in the mounting technology of the semiconductor device can be used.

A preferable composition of the encapsulant for an electronic circuit protective material includes a combination of an epoxy resin and a phenol resin as a curing agent. Examples of the epoxy resin include biphenyl type epoxy resin, bisphenol type (bisphenol F type, bisphenol A type, etc.) epoxy resin, triphenylmethane type epoxy resin, orthocresol novolac type epoxy resin, and naphthalene type epoxy resin. Examples of the phenol resin include a triphenylmethane type phenol resin, a phenol aralkyl type phenol resin, a zylock type phenol resin, a copolymerized phenol aralkyl type phenol resin, a naphthol aralkyl type phenol resin, and a biphenylene aralkyl type phenol resin. Each of these may be used alone or in combination of two or more.

<Seal method>
The sealing method of the present embodiment is to seal the periphery of the electronic circuit by combining the above-mentioned electronic circuit protection material and the above-mentioned sealing material for the electronic circuit protection material.

The method used for the sealing method is not particularly limited, and can be selected from those generally used in the mounting technology of semiconductor devices.

<Manufacturing method of semiconductor devices>
The method for manufacturing a semiconductor device of the present embodiment includes a step of applying the above-mentioned electronic circuit protective material around the electronic circuit to form a cured product of the electronic circuit protective material. The method of applying the electronic circuit protective material around the electronic circuit is not particularly limited, and a dispensing method, a casting method, a printing method, or the like can be adopted.

The above method may further include a step of sealing the periphery of the cured product formed by using the electronic circuit protective material with the above-mentioned electronic circuit sealing material. The method of sealing the periphery of the cured product of the electronic circuit protective material with a sealing material is not particularly limited, and a dispensing method, a casting method, a printing method, or the like can be adopted.

In the above method, the details of the electronic circuit protective material and the electronic circuit encapsulant are as described above. The electronic circuit may be, for example, a wire connecting the semiconductor chip and the substrate.

Hereinafter, the above-described embodiment will be specifically described with reference to Examples, but the above-described embodiment is not limited to these Examples. The unit of the item corresponding to each material in the table is "parts by mass", and the blank indicates that the corresponding material is not used.

(1) Preparation of Electronic Circuit Protective Material The materials shown in Table 1 were blended in the composition ratio shown in Table 1 and kneaded and dispersed with a three-roll roll and a vacuum grinder to prepare the electronic circuit protective material of the example. .. The viscosity of the prepared electronic circuit protective material at 25 ° C. and a shear rate of 10 ^-1 and the viscosity at 75 ° C. and a shear rate of 5 s ^-1 were measured, respectively. Further, the viscosity at 75 ° C. and a shear rate of 5s- ¹ was measured, and the fluctuation index at 75 ° C. was determined. The results are shown in Table 1.

(2) Evaluation of fluidity The fluidity of the electronic circuit protective material is the state of wire flow when the wire bonding structure formed using the PBGA (Plastic Ball Grid Array) package is sealed with the electronic circuit protective material. Was evaluated by.
Specifically, as shown in FIG. 1, the maximum displacement amount a of the wire after sealing the wire bonding structure with the electronic circuit protective material is confirmed by X-ray, and the maximum displacement amount a is the loop length b. The W / S (%) was obtained by multiplying the value divided by 100 by 100. When the value of W / S (%) was 3% or less, the liquidity was judged to be "good". The results are shown in Table 1.

(3) Evaluation of Chloride Ion Amount The chloride ion amount (ppm) of the electronic circuit protective material was measured by ion chromatography under the above-mentioned conditions. The results are shown in Table 2.

Details of the materials shown in Tables 1 and 2 are as follows.
Epoxy resin 1 ... p- (2,3-epoxypropoxy) -N, N-bis (2,3-epoxypropyl) aniline (ADEKA Corporation, trade name "EP-3950S", total chlorine content of 1500 ppm or less)
Epoxy resin 2 ... p- (2,3-epoxypropoxy) -N, N-bis (2,3-epoxypropyl) aniline (Mitsubishi Chemical Corporation, trade name "jER630", total chlorine content is 5500 ppm or less)
-Epoxy resin 3 ... Bisphenol F type epoxy resin (Nippon Steel & Sumitomo Metal Chemical Co., Ltd., trade name "YDF-8170C")
Epoxy resin 4 ... 1,6-hexanediol diglycidyl ether (Sakamoto Yakuhin Kogyo Co., Ltd., trade name "SR-16HL")
・ Curing agent: Diethyltoluenediamine (Mitsubishi Chemical Corporation, trade name "jER Cure W")
・ Ion trap agent: Bismuth-based ion trap agent (Toagosei Co., Ltd., trade name "IXE-500")
-Solar ... Butyl carbitol acetate-Inorganic filler 1 ... Spherical molten silica surface-treated with a silane coupling agent (Admatex Co., Ltd., trade name "SE5050-SEJ", volume average particle size 1.5 μm
-Inorganic filler 2 ... Spherical molten silica surface-treated with a silane coupling agent (Admatex Co., Ltd., trade name "SE2050-SEJ", volume average particle size 0.5 μm)

As shown in the results of Table 1, the protective materials for electronic circuits produced in Examples 1 to 3 showed excellent fluidity even when the content of the inorganic filler was 50% by mass or more of the whole.

As shown in the results of Table 2, the amount of chloride ions in Example 4 in which the epoxy resin 2 and the ion trap agent are used in combination is higher than that in Example 5 in which the high-purity epoxy resin 1 is used. However, it was 43 ppm as compared with 110 ppm of Reference Example 1 in which the ion trap agent was not used in combination, which was a sufficiently high level as a protective material for an electronic circuit.
In Reference Example 2, in which the amount of the inorganic filler was increased in order to reduce the amount of chloride ions, the amount of chloride ions was not evaluated because kneading with three rolls was not possible.

Claims (10)

A bisphenol type epoxy resin containing a resin component and an inorganic filler, the content of the inorganic filler is 50% by mass or more of the total, and the resin component is a liquid bisphenol type epoxy resin as an epoxy resin having an aromatic ring. An electronic circuit protective material containing at least one selected from the group consisting of glycidylamine type epoxy resins and a linear aliphatic epoxy resin as an aliphatic epoxy resin. The electronic circuit protective material according to claim 1, wherein the amount of chlorine ions is 100 ppm or less. The electronic circuit protective material according to claim 1 or 2, wherein the maximum particle size of the inorganic filler is 75 μm or less. The electronic circuit protective material according to any one of claims 1 to 3, wherein the viscosity measured at 75 ° C. and a shear rate of 5s- ^{1 is 3.0 Pa · s or less.} The electronic circuit protective material according to any one of claims 1 to 4, wherein the viscosity measured at 25 ° C. and a shear rate of 10 s- ^{1 is 30 Pa · s or less.} Assuming that the viscosity measured under the conditions of 75 ° C. and a shear rate of 5s ^-1 is viscosity A and the viscosity measured under the conditions of 75 ° C. and a shear rate of 50s ^-1 is viscosity B, the value of viscosity A / viscosity B is used. The electronic circuit protective material according to any one of claims 1 to 5, wherein the obtained shear index at 75 ° C. is 0.1 to 2.5. A combination of the electronic circuit protective material according to any one of claims 1 to 6 and a sealing material for an electronic circuit protective material for sealing the periphery of a cured product of the electronic circuit protective material is used as an electron. A sealing method that seals around the circuit. A method for manufacturing a semiconductor device, comprising a step of applying the electronic circuit protective material according to any one of claims 1 to 6 around an electronic circuit to form a cured product of the electronic circuit protective material. The method for manufacturing a semiconductor device according to claim 8 , further comprising a step of sealing the periphery of the cured product of the electronic circuit protective material with a sealing resin composition. The method for manufacturing a semiconductor device according to claim 8 or 9 , wherein the electronic circuit is a wire connecting a semiconductor chip and a substrate.

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