KR20220164718A - Method for manufacturing a resin molded material for semiconductor encapsulation, method for manufacturing a semiconductor package, and method for manufacturing a semiconductor device - Google Patents

Abstract

A manufacturing method of a resin molded material for semiconductor encapsulation, a manufacturing method of a semiconductor package, and a manufacturing method of a semiconductor device capable of further reducing the content of conductive foreign matter are provided. In a method for producing a resin molded material for semiconductor encapsulation, a mixture containing a thermosetting resin, a filler and a solvent is sprayed and dried.

Description

Method for manufacturing a resin molded material for semiconductor encapsulation, method for manufacturing a semiconductor package, and method for manufacturing a semiconductor device

The present invention relates to a method for manufacturing a resin molding for semiconductor encapsulation, a method for manufacturing a semiconductor package, and a method for manufacturing a semiconductor device.

A semiconductor package is for protecting a semiconductor element from an external impact by sealing a semiconductor element with a thermosetting resin, and is used by electrically connecting to a circuit board, for example, a main board of an electronic device. In recent years, a trend in technology development related to electronic devices is the narrowing of component sizes. Accordingly, even in the field of semiconductor packages, demand for small packages is rapidly increasing, and a semiconductor package capable of arranging a large number of connection terminals while being small in size is required.

As miniaturization and high performance progress in this way, the pitch of the metal wires inside the semiconductor package also narrows accordingly, and in recent years, the pitch of the metal wires exists of about 100 μm.

Since a resin molded material for semiconductor encapsulation containing a thermosetting resin is generally manufactured as a particulate material through each step of melting and kneading raw materials and crushing, conductive foreign matter is mixed from the raw material and manufacturing equipment such as a kneading machine and a crushing machine. do. The obtained resin molded material for semiconductor encapsulation is used in particulate form or after tableting with a tableting machine, it is used for encapsulation of semiconductor elements.

Examples of the conductive foreign matter include metals mixed in raw materials, metals generated from manufacturing facilities, aggregates of carbon used in raw materials, and coarse particles called carbon grids. When a semiconductor element is sealed using a resin molded material for semiconductor encapsulation in which conductive foreign matter is mixed, there is a risk that the conductive foreign matter may be caught between narrow-pitch metal wires and cause a short circuit.

Regarding the subject of reducing mixing of conductive foreign matter, for example, a method of obtaining a tablet by removing conductive foreign matter using a magnetic magnetic machine (for example, see Patent Literature 1) has been proposed. In addition, a method of obtaining a particulate material by dissolving a raw material in a solvent, removing conductive foreign matter with a magnetic magnetic machine in a state of low viscosity, drying it in a thin film form, and pulverizing has been proposed (for example, Patent Document 2 Reference). According to the method of Patent Literature 2, mixing of metal is suppressed because kneading and stranding are performed in a low-viscosity state.

Japanese Unexamined Patent Publication No. 2006-294677 Japanese Unexamined Patent Publication No. 2011-252041

However, in the removal method using a magnetic machine, it is possible to remove large-sized conductive metal foreign matter and ferromagnetic conductive metal foreign matter, but fine (for example, about 100 μm or less in diameter) conductive metal foreign matter and weakly magnetic conductive metal foreign matter. , and carbon coarse particles cannot be sufficiently removed.

The subject of this invention is providing the manufacturing method of the resin molded material for semiconductor encapsulation, the manufacturing method of a semiconductor package, and the manufacturing method of a semiconductor device which can further reduce content of a conductive foreign material.

Specific means for solving the above problems are as follows.

<1> A method for producing a resin molded material for semiconductor encapsulation, comprising spraying a mixture containing a thermosetting resin, a filler, and a solvent and drying the mixture.

<2> The method for producing a resin molded material for semiconductor encapsulation according to <1>, wherein the content of the solvent in the mixture is 10% by mass to 90% by mass.

<3> The method for producing a resin molded material for semiconductor encapsulation according to <1> or <2>, wherein the mixture has a viscosity of 0.001 Pa·s to 50 Pa·s at 25°C.

<4> The method for producing a resin molded material for semiconductor encapsulation according to any one of <1> to <3>, wherein the mixture is heated and sprayed.

<5> The method for producing a molded resin material for semiconductor encapsulation according to any one of <1> to <4>, wherein the volume average particle diameter of the molded resin material for semiconductor encapsulation is 100 μm to 3 mm.

<6> Manufacture of the resin molded material for semiconductor encapsulation according to any one of <1> to <5>, in which, before spraying the mixture, foreign matter is removed with at least one selected from the group consisting of a magnetic fan and a filter. Way.

<7> The method for producing a resin molded material for semiconductor encapsulation according to any one of <1> to <6>, wherein the mixture further contains at least one selected from the group consisting of a curing agent, a curing accelerator, a release agent, and a colorant.

<8> The manufacturing method of the semiconductor package which seals a semiconductor element using the resin molded material for semiconductor encapsulation obtained by the manufacturing method in any one of <1>-<6>.

<9> A method for manufacturing a semiconductor device using a semiconductor package obtained by the manufacturing method according to <8>.

ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the resin molded material for semiconductor encapsulation, the manufacturing method of a semiconductor package, and the manufacturing method of a semiconductor device which can further reduce content of a conductive foreign material can be provided.

In the present disclosure, the word "process" includes a process independent from other processes, as well as a process that cannot be clearly distinguished from other processes, as long as the purpose of the process is achieved.

In the numerical range indicated using "to" in the present disclosure, the numerical values described before and after "to" are included as the minimum and maximum values, respectively.

In the numerical ranges described stepwise during the present disclosure, the upper limit or lower limit of one numerical range may be replaced with the upper limit or lower limit of another stepwisely described numerical range. In addition, in the numerical range described in this indication, you may replace the upper limit value or the lower limit value of the numerical range with the value shown in the Example.

In this indication, each component may contain plural kinds of substances concerned. When a plurality of types of substances corresponding to each component are present in the composition, the content rate or content of each component means the total content rate or content of the plurality of types of substances present in the composition, unless otherwise specified.

In this indication, the particle|grains corresponding to each component may contain multiple types. When there are plural types of particles corresponding to each component in the composition, the particle size of each component means a value relating to a mixture of the plural types of particles present in the composition, unless otherwise specified.

In the present disclosure, the solid and liquid phases refer to the phases at 25°C.

<Method for Manufacturing Resin Molded Material for Semiconductor Encapsulation>

In the method for manufacturing a resin molding for semiconductor encapsulation of the present disclosure, a mixture containing a thermosetting resin, a filler and a solvent is sprayed (hereinafter also referred to as a “spraying step”) and dried (hereinafter also referred to as a “drying step”). The manufacturing method of the resin molded material for semiconductor encapsulation of this indication may have other processes, such as a preparation process of a mixture.

According to the method of the present disclosure, it is possible to further reduce the content of the conductive foreign matter compared to the conventional method. In particular, it is possible to effectively remove conductive foreign matter of 45 μm or more derived from a manufacturing apparatus used when manufacturing a resin molded material for semiconductor encapsulation, and it is possible to reduce short-circuit defects in narrow-pitch semiconductor devices.

In a conventional method for producing a resin molded material for semiconductor encapsulation, a mixture of raw materials is melt-kneaded with three rolls or the like, and furthermore, a twin-screw heating extruder is sometimes used. are continuing to contact. Therefore, conductive foreign matter is easily mixed in the mixture from metal members such as rolls. In addition, since the mixture has a high viscosity, it is difficult for the conductive foreign matter once incorporated to come out of the mixture. After the kneaded mixture is cooled, it is pulverized with a pulverizer to produce a particulate resin molded material for semiconductor encapsulation. The hard mixture after cooling rubs against the blade of the grinder, and conductive foreign matter is mixed as wear powder.

In addition, in the conventional method, since conductive foreign matter is mixed in each manufacturing step, the conductive foreign matter is removed after each step. For example, each of the raw material before preparing the mixture, the prepared mixture, and the pulverized resin molded material for semiconductor encapsulation are each subjected to removal of conductive foreign matter, which is a complicated process.

In addition, in the method of removing the conductive foreign matter using magnetic magnetic machines such as Patent Document 1 and Patent Document 2, as described above, the removal of fine conductive foreign matter and weakly magnetic conductive foreign matter is not sufficient. Further, in order to obtain the particulate matter, as in Patent Literature 2, pulverization by a pulverizer is finally required, and conductive foreign matter is mixed in this step.

In contrast, in the method of the present disclosure, since the raw material is dissolved in a solvent, the viscosity of the mixture can be reduced, and there is no friction with metal members such as grinding blades. Thereby, content of the conductive foreign material in the resin molded material for semiconductor encapsulation can be significantly reduced. In addition, the content of fine conductive foreign matter and weakly magnetic conductive foreign matter can also be suppressed.

Further, in the method of the present disclosure, the kneading step, the cooling step, the crushing step, and the conductive foreign material removal step after each step can be omitted, making it a simple method.

Hereinafter, the manufacturing method of the resin molded material for semiconductor encapsulation of this indication is demonstrated for each process.

(Preparation process of mixture)

In the preparation step of the mixture, the raw material of the resin molded material for semiconductor encapsulation and the solvent are mixed. As a raw material, it contains at least a thermosetting resin and a filler, and may further contain a hardening|curing agent, a hardening accelerator, a mold release agent, a coloring agent, etc. Moreover, you may contain additives generally used as a sealing material as a raw material.

The thermosetting resin is not particularly limited, and is preferably solid at 25°C from the viewpoint of workability or handleability. Specifically, an epoxy resin, an unsaturated polyester resin, a polyamide resin, a polyamideimide resin, a phenol resin, a melamine resin, etc. are mentioned, and it is preferable to contain an epoxy resin from a sealing property viewpoint. As an epoxy resin, what is normally used as a sealing material can be applied suitably.

A liquid thermosetting resin may be used in combination at 25 ° C, and the content of the solid thermosetting resin at 25 ° C relative to the total amount of the thermosetting resin solid at 25 ° C and the thermosetting resin liquid at 25 ° C is preferably 85% by mass or more, It is more preferably 90% by mass or more, more preferably 95% by mass or more, and particularly preferably 98% by mass or more. When the content of the solid thermosetting resin at 25 ° C. is within the above range, the handleability in the spraying step is excellent, and the uniformity of the particle diameter, particle shape, etc. of the obtained particulate resin molded material for semiconductor encapsulation tends to be excellent.

Specifically as the epoxy resin, a group consisting of phenolic compounds such as phenol, cresol, xylenol, resorcinol, catechol, bisphenol A and bisphenol F, and naphthol compounds such as α-naphthol, β-naphthol and dihydroxynaphthalene A novolak-type epoxy resin obtained by epoxidizing a novolak resin obtained by condensing or co-condensing at least one phenolic compound selected from phenol novolak-type epoxy resins, ortho-cresol novolac-type epoxy resins, etc.); Triphenylmethane-type epoxy resin obtained by epoxidizing a triphenylmethane-type phenolic resin obtained by condensation or co-condensation of the above phenolic compound with an aromatic aldehyde compound such as benzaldehyde and salicylaldehyde in the presence of an acidic catalyst; a copolymerization-type epoxy resin obtained by epoxidizing a novolac resin obtained by co-condensing the phenolic compound and the naphthol compound with an aldehyde compound in the presence of an acidic catalyst; diphenylmethane type epoxy resins that are diglycidyl ethers such as bisphenol A and bisphenol F; biphenyl-type epoxy resins that are alkyl-substituted or unsubstituted biphenol diglycidyl ether; stilbene-type epoxy resins that are diglycidyl ethers of stilbene-type phenol compounds; sulfur atom-containing epoxy resins that are diglycidyl ethers such as bisphenol S; epoxy resins that are glycidyl ethers of alcohols such as butanediol, polyethylene glycol, and polypropylene glycol; glycidyl ester type epoxy resins that are glycidyl esters of polyhydric carboxylic acid compounds such as phthalic acid, isophthalic acid and tetrahydrophthalic acid; glycidylamine-type epoxy resins obtained by substituting an active hydrogen bonded to a nitrogen atom such as aniline, diaminodiphenylmethane, or isocyanuric acid with a glycidyl group; dicyclopentadiene-type epoxy resins obtained by epoxidizing a co-condensation resin of dicyclopentadiene and a phenolic compound; Vinylcyclohexene diepoxide, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, 2-(3,4-epoxy)cyclohexyl-5, which is obtained by epoxidizing the olefin bond in the molecule. alicyclic epoxy resins such as ,5-spiro(3,4-epoxy)cyclohexane-m-dioxane; para-xylylene-modified epoxy resins that are glycidyl ethers of para-xylylene-modified phenol resins; metaxylylene-modified epoxy resins that are glycidyl ethers of meta-xylylene-modified phenol resins; terpene-modified epoxy resins that are glycidyl ethers of terpene-modified phenol resins; dicyclopentadiene-modified epoxy resins that are glycidyl ethers of dicyclopentadiene-modified phenol resins; cyclopentadiene-modified epoxy resins that are glycidyl ethers of cyclopentadiene-modified phenol resins; polycyclic aromatic ring-modified epoxy resins that are glycidyl ethers of polycyclic aromatic ring-modified phenol resins; naphthalene-type epoxy resins that are glycidyl ethers of naphthalene ring-containing phenol resins; halogenated phenol novolak type epoxy resins; Hydroquinone type epoxy resin; trimethylolpropane type epoxy resin; linear aliphatic epoxy resins obtained by oxidizing olefin bonds with peracids such as peracetic acid; aralkyl type epoxy resins obtained by epoxidizing aralkyl type phenol resins such as phenol aralkyl resins and naphthol aralkyl resins; etc. can be mentioned. Further, epoxidized products of silicone resins, epoxidized products of acrylic resins, and the like are also exemplified as epoxy resins.

As a filler, what is generally used as a sealing material can be applied suitably, and an inorganic filler is preferable. Specifically, as the material of the inorganic filler, fused silica, crystalline silica, glass, alumina, calcium carbonate, zirconium silicate, calcium silicate, silicon nitride, aluminum nitride, boron nitride, magnesium oxide, silicon carbide, beryllia, zirconia, zircon, phosphorus and inorganic materials such as territe, steatite, spinel, mullite, titania, talc, clay, and mica.

The shape of the filler is not particularly limited, and examples thereof include powder, spherical shape, fiber, and the like, and a spherical shape is preferable from the viewpoints of filling properties and reducing abrasion of sealing molds.

As the inorganic filler, spherical fused silica particles, crushed silica particles, and the like are preferable.

A filler may be used individually by 1 type, and may use 2 or more types together. In addition, "using two or more types of fillers" means, for example, when two or more types of fillers with the same component and different average particle diameters are used, when two or more types of fillers with the same average particle size and different components are used, and A case in which two or more types of fillers having different average particle diameters and types are used is exemplified.

The content rate of the filler is not particularly limited. From the viewpoint of further improving the properties of the cured product after encapsulation, such as the thermal expansion coefficient, thermal conductivity, and modulus of elasticity, the content of the filler is preferably 70% by mass to 95% by mass, and 75% by mass to 90% by mass of the entire resin molded material for semiconductor encapsulation. It is more preferable that it is mass %.

The content rate of the filler in the resin molded material for semiconductor encapsulation is measured as follows. First, the total mass of the cured product (molded product) of the resin molded material for semiconductor encapsulation is measured, the molded product is baked at 400°C for 2 hours and then at 700°C for 3 hours, the resin component is evaporated, and the mass of the remaining filler is measured. do. From each obtained mass, the mass ratio of the filler to the total mass of the resin molded material for semiconductor encapsulation is obtained, and the content of the filler is determined.

The average particle diameter of the filler is not particularly limited. For example, it is preferable that they are 0.1 micrometer - 150 micrometers, and, as for the volume average particle diameter of a filler, it is more preferable that they are 0.5 micrometer - 75 micrometers. The volume average particle diameter of the filler can be measured as the particle diameter (D50) when the accumulation from the small diameter side is 50% in the volume-based particle size distribution measured by the laser scattering diffraction method particle size distribution analyzer.

The curing agent is not particularly limited, and those generally used as sealing materials can be appropriately applied. For example, when using an epoxy resin as a thermosetting resin, a phenol curing agent, an amine curing agent, an acid anhydride curing agent, a polymercaptan curing agent, a polyaminoamide curing agent, an isocyanate curing agent, a block isocyanate curing agent, and the like are exemplified. From the viewpoint of improving heat resistance, the curing agent preferably has a phenolic hydroxyl group in its molecule (phenol curing agent). When a phenol curing agent is used, the permissible range of temperature control in the spraying step and the drying step is widened, and the particle size and particle shape of the particulate resin molded material for semiconductor encapsulation to be obtained tend to be excellent in uniformity.

Specific examples of the phenol curing agent include polyhydric phenol compounds such as resorcinol, catechol, bisphenol A, bisphenol F, and substituted or unsubstituted biphenol; In the group consisting of phenolic compounds such as phenol, cresol, xylenol, resorcin, catechol, bisphenol A, bisphenol F, phenylphenol, and aminophenol, and naphthol compounds such as α-naphthol, β-naphthol, and dihydroxynaphthalene a novolak-type phenolic resin obtained by condensing or co-condensing at least one selected phenolic compound with an aldehyde compound such as formaldehyde, acetaldehyde, propionaldehyde, benzaldehyde, salicylaldehyde, etc. under an acidic catalyst; Aralkyl type phenolic resins, such as phenolic aralkyl resin and naphthol aralkyl resin synthesized from the above phenolic compound and dimethoxyparaxylene, bis(methoxymethyl)biphenyl, and the like; para-xylylene and/or meta-xylylene-modified phenolic resins; melamine-modified phenolic resins; terpene-modified phenolic resins; dicyclopentadiene-type phenolic resins and dicyclopentadiene-type naphthol resins synthesized by copolymerization from the above phenolic compounds and dicyclopentadiene; cyclopentadiene-modified phenolic resins; polycyclic aromatic ring-modified phenolic resins; biphenyl type phenol resin; a triphenylmethane-type phenol resin obtained by condensing or co-condensing the above phenolic compound with an aromatic aldehyde compound such as benzaldehyde or salicylaldehyde in the presence of an acidic catalyst; and phenol resins obtained by copolymerizing two or more of these.

A curing agent may be used individually by 1 type, and may be used in combination of 2 or more type.

When an epoxy resin is used as the curable resin and the resin molding for semiconductor encapsulation contains a curing agent, the equivalent ratio of the epoxy resin and the curing agent, that is, the ratio of the number of functional groups in the curing agent to the number of epoxy groups in the epoxy resin (number of functional groups in the curing agent/epoxy The number of epoxy groups in the resin) is not particularly limited. From the viewpoint of suppressing each unreacted component to a small extent, the equivalence ratio is preferably set in the range of 0.5 to 2.0, more preferably in the range of 0.7 to 1.2.

As the curing accelerator, it is not particularly limited, and those generally used as sealing materials can be appropriately applied.

Examples of the curing accelerator include diazabi such as 1,5-diazabicyclo[4.3.0]nonene-5 (DBN) and 1,8-diazabicyclo[5.4.0]undecene-7 (DBU). cyclic amidine compounds such as cycloalkenes, 2-methylimidazoles, 2-phenylimidazoles, 2-phenyl-4-methylimidazoles, and 2-heptadecylimidazoles; derivatives of the above cyclic amidine compounds; phenol novolac salts of the above cyclic amidine compounds or derivatives thereof; These compounds include maleic anhydride, 1,4-benzoquinone, 2,5-toluquinone, 1,4-naphthoquinone, 2,3-dimethylbenzoquinone, 2,6-dimethylbenzoquinone, 2,3-dimethine quinone compounds such as toxy-5-methyl-1,4-benzoquinone, 2,3-dimethoxy-1,4-benzoquinone, phenyl-1,4-benzoquinone, diazophenylmethane, etc. a compound having intramolecular polarization formed by adding a compound having; Cyclic amidinium compounds, such as the tetraphenyl borate salt of DBU, the tetraphenyl borate salt of DBN, the tetraphenyl borate salt of 2-ethyl-4-methylimidazole, and the tetraphenyl borate salt of N-methylmorpholine; tertiary amine compounds such as pyridine, triethylamine, triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, and tris(dimethylaminomethyl)phenol; derivatives of the above tertiary amine compounds; ammonium salt compounds such as tetra-n-butylammonium acetate, tetra-n-butylammonium phosphate, tetraethylammonium acetate, tetra-n-hexylammonium benzoate, and tetrapropylammonium hydroxide; Triphenylphosphine, diphenyl (p-tolyl) phosphine, tris (alkylphenyl) phosphine, tris (alkoxyphenyl) phosphine, tris (alkylalkoxyphenyl) phosphine, tris (dialkylphenyl) phosphine, tris (trialkylphenyl) phosphine, tris (tetraalkylphenyl) phosphine, tris (dialkoxyphenyl) phosphine, tris (trialkoxyphenyl) phosphine, tris (tetraalkoxyphenyl) phosphine, trialkylphosphine, di tertiary phosphines such as alkylarylphosphines and alkyldiarylphosphines; Phosphine compounds, such as the complex of the said tertiary phosphine and organic boron; The tertiary phosphine or the phosphine compound and maleic anhydride, 1,4-benzoquinone, 2,5-toluquinone, 1,4-naphthoquinone, 2,3-dimethylbenzoquinone, 2,6-dimethyl Quinone compounds such as benzoquinone, 2,3-dimethoxy-5-methyl-1,4-benzoquinone, 2,3-dimethoxy-1,4-benzoquinone, phenyl-1,4-benzoquinone, and diazo compounds having intramolecular polarization obtained by adding a compound having a π bond, such as phenylmethane; The tertiary phosphine or the phosphine compound and 4-bromophenol, 3-bromophenol, 2-bromophenol, 4-chlorophenol, 3-chlorophenol, 2-chlorophenol, 4-iodinated phenol, 3 -iodinated phenol, 2-iodinated phenol, 4-bromo-2-methylphenol, 4-bromo-3-methylphenol, 4-bromo-2,6-dimethylphenol, 4-bromo-3,5- Dimethylphenol, 4-bromo-2,6-di-t-butylphenol, 4-chloro-1-naphthol, 1-bromo-2-naphthol, 6-bromo-2-naphthol, 4-bromo- Compounds having intramolecular polarization obtained by reacting a halogenated phenol compound such as 4'-hydroxybiphenyl and then passing through a step of dehydrohalogenation; tetra-substituted phosphoniums such as tetraphenylphosphonium, tetra-substituted phosphoniums without a phenyl group bonded to a boron atom such as tetra-p-tolyl borate, and tetra-substituted borates; The salt of tetraphenylphosphonium and a phenolic compound, etc. are mentioned.

A hardening accelerator may be used individually by 1 type, and may be used in combination of 2 or more type.

When the resin molded material for semiconductor encapsulation contains a curing accelerator, the content of the curing accelerator is not particularly limited, and is, for example, 0.1% by mass to 5.0% by mass with respect to 100 parts by mass of the resin component (ie, the sum of the resin and the curing agent). It is preferable, and considering the fluidity of the resin molded material for semiconductor encapsulation, it is more preferable that it is 0.15 mass % - 0.35 mass %.

As a release agent, it is not specifically limited, What is generally used as a sealing material can be applied suitably. Specific examples of the release agent include higher fatty acids such as carnauba wax, montanic acid and stearic acid, metal salts of higher fatty acids, ester waxes such as montanic acid esters, and polyolefin waxes such as oxidized polyethylene and non-oxidized polyethylene. .

A mold release agent may be used individually by 1 type, and may be used in combination of 2 or more type.

When the resin molded material for semiconductor encapsulation contains a release agent, the content of the release agent is preferably 0.01 part by mass to 10 parts by mass, more preferably 0.1 part by mass to 5 parts by mass with respect to 100 parts by mass of the resin component. When the content of the release agent is 0.01 part by mass or more with respect to 100 parts by mass of the resin component, the release property tends to be sufficiently obtained. When the content of the release agent is 10 parts by mass or less with respect to 100 parts by mass of the resin component, better adhesion tends to be obtained. In addition, the mixture containing the mold release agent tends to be suppressed from adhering to the inner wall of the drying tower during spray drying. Therefore, the use of a mold release agent tends to suppress the incorporation of foreign matter from the inner wall of the drying tower and also tends to improve the yield. Further, from the viewpoint of preventing adhesion, a fluorine coating or silicone coating may be applied to the inner wall of the drying tower.

The coloring agent is not particularly limited, and conventionally known ones can be used. Examples of the colorant include known colorants such as carbon black, organic dyes, organic pigments, titanium oxide, lead, and bengala. The content of the colorant can be appropriately selected according to the purpose and the like.

A coloring agent may be used individually by 1 type, and may be used in combination of 2 or more type.

As other additives, an ion exchanger, a flame retardant, a silane coupling agent, a stress reliever, etc. are mentioned. In addition to these, the resin molded material for semiconductor encapsulation may contain various additives commonly used in the art as needed.

The ion exchanger is not particularly limited, and conventionally known ones can be used. Specifically, a hydrotalcite compound and a hydrous oxide of at least one element selected from the group consisting of magnesium, aluminum, titanium, zirconium, and bismuth, and the like are exemplified.

An ion exchanger may be used individually by 1 type, and may be used in combination of 2 or more type.

When the resin molded material for semiconductor encapsulation contains an ion exchanger, the content of the ion exchanger is not particularly limited as long as it is sufficient to capture ions such as halogen ions. For example, the content of the ion exchanger is preferably 0.1 part by mass to 30 parts by mass, more preferably 1 part by mass to 10 parts by mass, based on 100 parts by mass of the resin component.

The flame retardant is not particularly limited, and conventionally known ones can be used. Specifically, an organic or inorganic compound containing a halogen atom, an antimony atom, a nitrogen atom or a phosphorus atom, a metal hydroxide, and the like are exemplified.

A flame retardant may be used individually by 1 type, and may be used in combination of 2 or more type.

The silane coupling agent is not particularly limited, and conventionally known ones can be used. Specifically, vinyltrichlorosilane, vinyltriethoxysilane, vinyltris(β-methoxyethoxy)silane, γ-methacryloxypropyltrimethoxysilane, β-(3,4-epoxycyclohexyl)ethyl Trimethoxysilane, γ-glycidoxypropyltrimethoxysilane, vinyltriacetoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-[bis(β-hydroxy Ethyl)] aminopropyltriethoxysilane, N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane, γ-(β-aminoethyl)aminopropyldimethoxymethylsilane, N-(trimethoxysilyl Propyl) ethylenediamine, N-(dimethoxymethylsilylisopropyl)ethylenediamine, methyltrimethoxysilane, methyltriethoxysilane, N-β-(N-vinylbenzylaminoethyl)-γ-aminopropyltrimethoxy Silane, γ-chloropropyltrimethoxysilane, hexamethyldisilane, γ-anilino propyltrimethoxysilane, vinyltrimethoxysilane, γ-mercaptopropylmethyldimethoxysilane, and the like are exemplified.

A silane coupling agent may be used individually by 1 type, and may be used in combination of 2 or more type.

The stress reliever is not particularly limited, and conventionally known ones can be used. Specifically, thermoplastic elastomers such as silicone, styrene, olefin, urethane, polyester, polyether, polyamide, and polybutadiene, NR (natural rubber), NBR (acrylonitrile-butadiene rubber), Rubber particles such as acrylic rubber, urethane rubber, and silicone powder, core-shells such as methyl methacrylate-styrene-butadiene copolymer (MBS), methyl methacrylate-silicone copolymer, and methyl methacrylate-butyl acrylate copolymer rubber particles having a structure; and the like.

A stress reliever may be used individually by 1 type, and may be used in combination of 2 or more type.

The solvent is not particularly limited as long as it can dissolve or disperse the raw material of the resin molded material for semiconductor encapsulation. For example, at least one selected from the group consisting of hydrocarbons, esters, ketones, and alcohols may be used from the viewpoint of low environmental load and easy dissolution of raw materials. Among them, when the solvent is ketones, it is particularly easy to dissolve the thermosetting component. The solvent is selected from the group consisting of benzene, toluene, cyclohexanone, acetone, methyl ethyl ketone, and methyl isobutyl ketone (MIBK) from the viewpoint of less volatilization at room temperature (25 ° C.) and easy removal during drying At least one type may be used.

A solvent may be used individually by 1 type, and may be used in combination of 2 or more type.

The content of the solvent in the mixture is not particularly limited. In the spraying step, which is the next step, it is preferable to appropriately adjust the viscosity of the mixture so that particles of a desired size are obtained. Therefore, the content of the solvent in the mixture is also preferably adjusted appropriately according to the desired viscosity of the mixture.

Specifically, the content of the solvent in the mixture is preferably 10% by mass to 90% by mass. When the solvent content is 10% by mass or more, the viscosity of the mixture is appropriately suppressed and spraying becomes easy. As for the content rate of the solvent in a mixture, 20 mass % - 70 mass % are more preferable. When the content of the solvent is 20% by mass to 70% by mass, the stability and productivity of spraying tend to be better.

The viscosity of the mixture at 25°C is preferably from 0.001 Pa·s to 50 Pa·s, and more preferably from 1 Pa·s to 30 Pa·s. When the mixture has a viscosity of 0.001 Pa·s or more at 25° C., separation of the filler and the curable resin after spraying is suppressed, and the obtained resin molded material for semiconductor encapsulation tends to have excellent fluidity when encapsulated. When the viscosity of the mixture at 25°C is 50 Pa·s or less, the stability of the spray tends to be excellent.

In the present disclosure, the viscosity of the mixture is measured at 25° C. and at a rotational speed of 20 revolutions/minute (rpm) to 60 revolutions/minute (rpm) using an E-type viscometer or a B-type viscometer.

The method of mixing the raw material and the solvent is not particularly limited, and may be mixed by a mixer.

Examples of the mixer include an agitation mixer using a stirring blade, a three-roll, two-axis continuous kneader, a self-revolution mixer, a static mixer, and a planetary mixer. It is preferable to set the stirring time and stirring speed appropriately.

The raw material and the solvent may be mixed together in their entire amount, or may be mixed by adding the remaining amount after mixing a part of them.

(Foreign matter removal process)

The mixture obtained above may remove foreign matter by at least one selected from the group consisting of magnetic fan and filter before the next spraying step and drying step. The foreign matter removal step may be performed after the spraying step and the drying step, but the foreign matter removal efficiency is superior when the foreign matter removal is performed with respect to a liquid (slurry state) mixture than after using the solid particulate matter.

In the foreign matter removal step, in addition to conductive foreign matter such as conductive metal foreign matter, general foreign matter such as non-conductive foreign matter may be removed. Examples of conductive foreign substances other than conductive metal foreign substances include coarse particles of carbon, and examples of non-conductive foreign substances include corrosive foreign substances containing elements such as halogen and sulfur.

The magnetic magnetic machine is not particularly limited, as long as it can attract the conductive foreign matter by magnetic force and separate the conductive foreign matter from the mixture. As a magnetic magnetic machine, the magnetic magnetic machine described in Unexamined-Japanese-Patent No. 9-173890, Unexamined-Japanese-Patent No. 2004-9005 etc. is mentioned, for example.

As the filter, a general filter used for foreign material removal may be used, and a cartridge filter, a fiber filter medium, a strainer, a magnet filter, and the like are exemplified, and a magnet filter is preferably used. A magnetic filter and a general filtration filter may be used together.

(spray process, drying process)

The mixture obtained above is sprayed and dried. In this way, a particulate resin molded material for semiconductor encapsulation is obtained. Although the spraying process and the drying process may be independent processes, it is preferable to dry while spraying. As a method of drying while spraying, a method of using a spray drying apparatus is exemplified.

In the spray drying apparatus, the mixture (slurry) is sprayed from the top in the vertical direction into an appropriately heated drying air flow. As a result, the solvent in the mixture is removed, and a solid granular material is obtained. You may use air, nitrogen gas, etc. for a dry air flow. A nozzle method, a disk method, etc. are mentioned as a method of spraying with a spray dryer.

In the spray drying apparatus, it is preferable to appropriately set the inlet temperature and the outlet temperature from the viewpoint of adjusting the particle size of the resin molded material for semiconductor encapsulation, removing the solvent, and the like. The inlet temperature and the outlet temperature can be appropriately adjusted depending on the type and concentration of raw materials and solvents. Moreover, it is preferable to set suitably also about spraying speed|rate. The spray rate can also be appropriately adjusted depending on the type, concentration, etc. of raw materials and solvents.

In the spraying step and the drying step, the slurry may be heated and sprayed so that the solvent is easily removed. The temperature of this heating can be set appropriately, and may be, for example, 30°C or higher, 35°C or higher, or 40°C or higher.

Further, from the viewpoint of suppressing volatilization of the solvent in the material storage container, the slurry may be cooled and then sprayed. The temperature of this cooling can be set appropriately, and it is good also as 23 degrees C or less, and good also as 20 degrees C or less, for example.

The assembled resin molded material for semiconductor encapsulation falls by gravity, and is collected and collected from the lower part in the vertical direction of the spray drying apparatus by a cyclone, bag filter, or the like. You may collect|recover the whole quantity of the particulate resin molded material for semiconductor encapsulation to a bag filter, without passing through a cyclone. In addition, the removed solvent may be recovered by a condenser.

The volume average particle diameter of the assembled resin molded material for semiconductor encapsulation is preferably 100 μm to 3 mm, more preferably 200 μm to 1 mm, still more preferably 220 μm to 1 mm. When the volume average particle diameter is 100 μm or more, the collection efficiency is improved, and the flowability at the time of sealing with the obtained resin molded material for semiconductor encapsulation tends to be excellent. When the volume average particle size is 3 mm or less, appearance defects tend to be suppressed during tablet molding. The assembled resin molded material for semiconductor encapsulation may be an irregular secondary aggregate formed by further aggregation of an irregular primary aggregate of several fillers.

In the present disclosure, the volume average particle diameter of the resin molded material for semiconductor encapsulation is measured by a laser diffraction method and can be measured by using a laser diffraction scattering particle size distribution analyzer (eg, LS230 manufactured by Beckman Coulter).

(sieve process)

The particulate resin molded material for semiconductor encapsulation recovered from the spray drying apparatus may be further separated through a sifting process. In the sifting process, a sieve such as a vibrating sieve can be used. In the sifting step, at least one of coarse powder and fine powder may be removed depending on the semiconductor element to be applied.

(tablet molding)

The particulate resin molded material for semiconductor encapsulation may be used for encapsulation of a semiconductor element in particulate form, or may be used for encapsulation of a semiconductor element after tablet molding. Tablet molding can be performed by a general method for sealing materials.

(Resin molded material for semiconductor sealing)

In the resin molded material for semiconductor encapsulation according to the present disclosure, conductive foreign matter having a diameter of about 45 μm or more can be effectively removed compared to the conventional ones. Also, the content of conductive foreign matter having a diameter of about 100 μm or less can be reduced. Furthermore, the content of the weakly magnetically conductive foreign matter can also be reduced. It is possible to make the maximum particle size of the conductive foreign matter in the resin molded material for semiconductor encapsulation 45 μm or less.

The resin molded material for semiconductor encapsulation according to the present disclosure can be suitably applied even if the wire pitch is 150 μm or less, and even if it is a semiconductor element with a wire pitch of 100 μm or less.

<Method of manufacturing semiconductor package>

In the method for manufacturing a semiconductor package of the present disclosure, a semiconductor element is sealed using a resin molded material for semiconductor encapsulation obtained by the above-described manufacturing method. Examples of methods for sealing semiconductor elements include transfer molding, injection molding, compression molding, and casting. In the transfer molding method, a tableted resin molded material for semiconductor encapsulation is often used, and in the compression molding method, a particulate resin molded material for semiconductor encapsulation is often used. However, the relationship between the sealing method and the shape of the resin molded material for semiconductor encapsulation is not limited to these. A transfer molding method, an injection molding method, a compression molding method, casting, and the like can be applied as general methods in the field of semiconductor element sealing.

As a semiconductor element, active elements, such as a semiconductor chip, a transistor, a diode, and a thyristor, and passive elements, such as a capacitor, a resistor, and a coil, etc. are mentioned.

More specifically, the DIP (Dual Inline Package), PLCC (Plastic Leaded Chip Carrier), QFP (Quad Flat Package), SOP (Small Outline Package), SOJ (Small Outline J-lead package), TSOP (Thin Small Outline Package), TQFP (Thin Quad Flat Package) ) and the like; TCP (Tape Carrier Package) having a structure in which a semiconductor element connected to a tape carrier by bumps is sealed with a resin molded material for semiconductor encapsulation; A COB (Chip On Board) module, hybrid IC, multichip having a structure in which semiconductor elements connected to wiring formed on a support member by wire bonding, flip chip bonding, solder, etc. are sealed with a resin molding material for semiconductor encapsulation modules, etc.; A semiconductor element is mounted on the surface of a support member having terminals for connection to a wiring board formed on the back surface, and after connecting the semiconductor element and wiring formed on the support member by bump or wire bonding, the semiconductor element is sealed with a resin molded material for semiconductor encapsulation. BGA (Ball Grid Array), CSP (Chip Size Package), MCP (Multi Chip Package), etc. which have a sealed structure are mentioned. Moreover, also in a printed wiring board, the resin molded material for semiconductor encapsulation can be used suitably.

<Method of manufacturing semiconductor device>

The semiconductor device manufacturing method of the present disclosure uses a semiconductor package obtained by the manufacturing method described above. Examples of semiconductor devices include those in which semiconductor packages are mounted on support members such as lead frames, wired tape carriers, wiring boards, glass, silicon wafers, and organic substrates.

Example

Next, the present invention will be described by examples, but the scope of the present invention is not limited to these examples.

[Example 1]

First, each component shown below was prepared.

[Epoxy resin]

Biphenyl type epoxy resin (YX-4000H, Mitsubishi Chemical Corporation, trade name): 100 parts by mass

[phenol resin]

Phenol aralkyl resin (XL-225-3L, Mitsui Chemicals, Inc., trade name): 90 parts by mass

[Curing accelerator]

Triphenylphosphine: 3 parts by mass

[filler a]

Spherical fused silica having an average particle diameter of 30 μm: 700 parts by mass

[filler b]

Spherical fused silica having an average particle diameter of 1 µm: 100 parts by mass

[release agent]

Carnauba wax: 3 parts by mass

Each component was blended in the above ratio, 100 ml (80 g) of acetone was added as a dissolving solvent, 30 rotations/min for 10 minutes in a planetary mixer, and 100 ml (80 g) of acetone was added for 100 rotations/min for 30 minutes. , It was heated and stirred at 35°C to prepare a slurry (solid content: 86% by mass, viscosity at 25°C: 0.02 Pa·s). The prepared slurry was filtered with a magnet filter equipped with a magnet of 11,000 gauss, and then further filtered using a polypropylene filter with a filtration accuracy of 40 µm.

Next, spray dryer B-290 (Nippon Buki Co., Ltd., trade name) was set to an inlet temperature of 90 ° C and an outlet temperature of 60 ° C, and the slurry cooled to 20 ° C was sprayed at 20 ml / min to obtain a granular semiconductor encapsulation resin I got the molding material.

[Example 2]

In Example 1, except that the inlet temperature is 25 ° C., the outlet temperature is 25 ° C., and the slurry cooled to 20 ° C. is sprayed at 10 ml / min, in the same manner as in Example 1, a particulate resin molded material for semiconductor encapsulation is prepared Got it.

[Example 3]

In Example 1, a particulate resin molded material for semiconductors was obtained in the same manner as in Example 1 except that the slurry was sprayed in a state where the temperature of the slurry was heated to 40°C.

[Example 4]

In Example 2, except that the slurry was sprayed in a state where the temperature of the slurry was heated to 40°C, it was carried out in the same manner as in Example 2 to obtain a particulate resin molded material for semiconductors.

[Comparative Example 1]

Each component shown in Example 1 was blended in the ratio of Example 1, the blended ingredients were mixed with a Henschel mixer, and then heated and kneaded with an extrusion kneader. After the obtained kneaded product was stretched into a sheet shape, a particulate resin composition for semiconductor encapsulation was obtained using a pulverizer.

<Measurement of Maximum Particle Diameter of Conductive Foreign Matter>

The particulate resin molded material for semiconductor encapsulation of Examples and Comparative Examples was dissolved in acetone, and a filler (silica particle) and conductive foreign matter were taken out from the resin molded material for semiconductor encapsulation, and the maximum particle size of the conductive foreign matter was measured using an optical microscope. . The results are shown in Table 1.

As shown in Table 1, according to the manufacturing method of the resin molded material for semiconductor encapsulation of the present disclosure, it is possible to remove conductive foreign matter and obtain a highly reliable resin molded material for semiconductor encapsulation.

As for the indication of Japanese Patent Application No. 2020-069193, the whole is taken in into this indication by reference.

All documents, patent applications, and technical standards in this disclosure are by reference in this disclosure to the same extent as when each document, patent application, and technical standard is specifically incorporated by reference and is individually described. introduced

Claims (9)

A method for producing a resin molding for semiconductor encapsulation, wherein a mixture containing a thermosetting resin, a filler and a solvent is sprayed and dried. The method for producing a resin molded material for semiconductor encapsulation according to claim 1, wherein the content of the solvent in the mixture is 10% by mass to 90% by mass. The method for producing a resin molded material for semiconductor encapsulation according to claim 1 or 2, wherein the mixture has a viscosity of 0.001 Pa·s to 50 Pa·s at 25°C. The method for producing a resin molded material for semiconductor encapsulation according to any one of claims 1 to 3, wherein the mixture is heated and sprayed. The method for producing a molded resin material for semiconductor encapsulation according to any one of claims 1 to 4, wherein the volume average particle diameter of the molded resin material for semiconductor encapsulation is 100 μm to 3 mm. The method for producing a resin molded material for semiconductor encapsulation according to any one of claims 1 to 5, wherein foreign substances are removed by using at least one selected from the group consisting of a magnetizer and a filter before spraying the mixture. The method for producing a resin molded material for semiconductor encapsulation according to any one of claims 1 to 6, wherein the mixture further contains at least one selected from the group consisting of a curing agent, a curing accelerator, a release agent, and a colorant. A method for manufacturing a semiconductor package, wherein a semiconductor element is sealed using the resin molded material for semiconductor encapsulation obtained by the manufacturing method according to any one of claims 1 to 6. A method for manufacturing a semiconductor device using a semiconductor package obtained by the manufacturing method according to claim 8.