CN115298280A - Adhesive for semiconductor, and semiconductor device and method of manufacturing the same - Google Patents

Abstract

An adhesive for a semiconductor including a connection structure in which a semiconductor chip and respective connection portions of a printed circuit board are electrically connected to each other and/or a connection structure in which respective connection portions of a plurality of semiconductor chips are electrically connected to each other The semiconductor device is used for sealing of connecting parts, the adhesive for semiconductor contains a curable resin component, a flux and an inorganic filler, and the content of the inorganic filler is based on the total amount of the adhesive for a semiconductor of 60-60 95 mass %, the thermal conductivity after curing of the adhesive for semiconductors is 1.5 W/mK or more.

Description

Adhesive for semiconductor, semiconductor device and manufacturing method thereof

technical field

The present invention relates to an adhesive for semiconductors, a semiconductor device and a manufacturing method thereof.

Background technique

In the past, in order to connect semiconductor chips and substrates, wire bonding methods using thin metal wires such as gold wires (wires) have been widely used. A flip-chip connection method (FC connection method) in which a semiconductor chip and a substrate are directly connected by forming conductive protrusions called bumps on the semiconductor chip is becoming more and more popular.

As the flip-chip connection method, there are known methods of metal bonding using solder, tin, gold, silver, copper, etc., methods of metal bonding by applying ultrasonic vibration, and methods of maintaining mechanical contact by the shrinkage force of resin. From the viewpoint of the reliability of the connection portion, a method of metal bonding using solder, tin, gold, silver, copper, or the like is generally employed.

For example, COB (Chip On Board: Chip On Board) is widely used in BGA (Ball Grid Array: Ball Grid Array), CSP (Chip Size Package: Chip Size Package), etc. in the connection between semiconductor chips and substrates. The type connection method is also a flip chip connection method. Moreover, the flip-chip connection method is also widely used in a COC (Chip On Chip: stacked chip) type connection method in which bumps or wiring are formed on semiconductor chips and connected between semiconductor chips (for example, refer to the following patent documents 1).

In packages that are strongly required to be further miniaturized, thinner, and more functional, chip stacked packages, POP (Package On Package), and TSV (Through- Silicon Via (silicon through hole) and so on have also begun to be widely used. Since the packaging can be reduced by arranging in a three-dimensional shape instead of a planar shape, these technologies are widely used, and are also effective for improving the performance of semiconductors, reducing noise, reducing mounting area, and saving power. As the next generation of semiconductor wiring technology has received attention.

Previous technical literature

patent documents

Patent Document 1: Japanese Patent Laid-Open No. 2008-294382

Contents of the invention

The technical problem to be solved by the invention

In the flip-chip connection method described above, flip-chip connection may be performed through an adhesive for semiconductors for the purpose of protecting the metal bonding of the connection portion or the like.

In flip-chip packaging, higher functionality and higher integration have been progressing in recent years. However, with higher functionality and higher integration, the pitch between wirings has become narrower, and thus the amount of heat generated in the package has increased. If heat is accumulated in the package, the semiconductor chip will become high temperature, which may cause failure. Therefore, more excellent heat dissipation properties than conventional ones are required for adhesives for semiconductors.

Therefore, an object of the present invention is to provide an adhesive for semiconductors excellent in heat dissipation. Furthermore, an object of the present invention is to provide a semiconductor device using such an adhesive for a semiconductor and a method for manufacturing the same.

Means for solving technical problems

One aspect of the present invention provides an adhesive for semiconductors comprising a connection structure in which respective connection portions of a semiconductor chip and a printed circuit board are electrically connected to each other and/or the respective connection portions of a plurality of semiconductor chips are electrically connected to each other. It is used for sealing the connection part in a semiconductor device with a connected structure. The adhesive for semiconductors contains curable resin components, fluxes, and inorganic fillers. Based on the total amount of adhesives for semiconductors, the content of inorganic fillers It is 60 to 95% by mass, and the thermal conductivity of the adhesive for semiconductors after curing is 1.5 W/mK or more.

The above-mentioned inorganic filler may contain polyhedral alumina.

The inorganic filler may contain at least one selected from the group consisting of silicon carbide, boron nitride, diamond, silicon dioxide, and aluminum nitride.

In the volume-based particle size distribution, the above-mentioned inorganic filler may have peaks in the respective ranges of 0.1 to 4.5 μm and 5 to 20 μm.

The above-mentioned binder for semiconductors may contain polyhedral alumina having a volume-based average particle diameter _r1 of 5 to 20 μm and volume-based average particle diameter _r2 of 0.1 to 4.5 μm as inorganic fillers.

The difference (r ₁ −r ₂ ) between the above average particle diameter r ₁ and the above average particle diameter r ₂ may be 4 to 10 μm.

The thermal conductivity of the adhesive for semiconductors after curing may be 3.0 W/mK or more.

The above-mentioned flux may be carboxylic acid.

The curable resin component may contain a thermosetting resin, a curing agent, and a thermoplastic resin.

Another aspect of the present invention provides a method of manufacturing a semiconductor device including a connection structure in which connection portions of a semiconductor chip and a printed circuit board are electrically connected to each other and/or each of a plurality of semiconductor chips. In the connection structure in which connection parts are electrically connected to each other, the manufacturing method of the semiconductor device includes the step of sealing at least a part of the connection part with the above-mentioned adhesive for semiconductor.

Another aspect of the present invention provides a semiconductor device including: a connection structure in which connection portions of a semiconductor chip and a printed circuit board are electrically connected to each other; and/or connection portions of a plurality of semiconductor chips are electrically connected to each other. The resulting connection structure; and a sealing material for sealing at least a part of the connection portion, the sealing material includes a cured product of the above-mentioned adhesive for semiconductors.

Invention effect

According to the present invention, it is possible to provide an adhesive for semiconductors excellent in heat dissipation. Furthermore, according to the present invention, it is possible to provide a semiconductor device using such an adhesive for a semiconductor and a method for manufacturing the same.

Description of drawings

FIG. 1 is a schematic cross-sectional view showing an embodiment of a semiconductor device according to the present invention.

2 is a schematic cross-sectional view showing another embodiment of the semiconductor device according to the present invention.

3 is a schematic cross-sectional view showing another embodiment of the semiconductor device according to the present invention.

4 is a schematic cross-sectional view showing an example of a method of manufacturing the semiconductor device shown in FIG. 3 .

5 is a schematic cross-sectional view showing another embodiment of the semiconductor device according to the present invention.

Detailed ways

Hereinafter, modes for implementing the present invention will be described in detail with reference to the drawings as the case may be. However, the present invention is not limited to the following embodiments. In addition, in this specification, "(meth)acrylic acid" means acrylic acid or methacrylic acid, and "(meth)acrylate" means acrylate or the methacrylate corresponding to it. "A or B" should just include either one of A and B, and may include both.

Moreover, in this specification, the numerical range represented using "-" shows the range which includes the numerical value described before and after "-" as a minimum value and a maximum value, respectively. In addition, within the numerical ranges described step by step in this specification, the upper limit or lower limit of the numerical range of a certain step may be replaced with the upper limit or lower limit of the numerical range of another step. In addition, within the numerical range described in this specification, the upper limit or lower limit of the numerical range may be replaced with the value shown in the Examples.

<Adhesives for semiconductors>

The adhesive for semiconductors according to the present embodiment is provided with a connection structure in which connection portions of a semiconductor chip and a printed circuit board are electrically connected to each other and/or is formed by electrically connecting connection portions of a plurality of semiconductor chips to each other. The semiconductor adhesive used for sealing the connection part in the semiconductor device of the connection structure contains a curable resin component, a flux and an inorganic filler. Based on the total amount of the semiconductor adhesive, the content of the inorganic filler is 60~ 95% by mass, and the thermal conductivity of the semiconductor adhesive after curing is 1.5W/mK or more.

(curable resin component)

The curable resin component may contain (a) a thermosetting resin, (b) a curing agent, and (c) a thermoplastic resin.

((a) thermosetting resin)

Examples of thermosetting resins include epoxy resins, urea resins, melamine resins, and phenol resins. From the viewpoint of good curability and excellent adhesiveness, the thermosetting resin may be an epoxy resin. The thermosetting resins can be used alone or in combination of two or more.

Examples of the epoxy resin include epoxy resins having two or more epoxy groups in the molecule, such as bisphenol A type epoxy resins, bisphenol F type epoxy resins, naphthalene type epoxy resins, Phenol novolak type epoxy resin, cresol novolak type epoxy resin, phenol aralkyl type epoxy resin, biphenyl type epoxy resin, triphenylmethane type epoxy resin, dicyclopentadiene type epoxy resin Resins, various multifunctional epoxy resins. These epoxy resins can be used individually by 1 type or in combination of 2 or more types.

The content of the epoxy resin may be 40 parts by mass or more or 50 parts by mass or more with respect to 100 parts by mass of the curing agent resin component. The content of the epoxy resin may be 90 parts by mass or less or 80 parts by mass or less with respect to 100 parts by mass of the curing agent resin component.

The content of the epoxy resin may be 10 parts by mass or more or 20 parts by mass or more with respect to 100 parts by mass of the adhesive for semiconductors. The content of the epoxy resin may be 50 parts by mass or less or 40 parts by mass or less with respect to 100 parts by mass of the adhesive for semiconductors. The content of the epoxy resin may be 10 to 50 parts by mass relative to 100 parts by mass of the adhesive for semiconductors.

((b) curing agent)

Examples of the curing agent include phenolic resin-based curing agents, acid anhydride-based curing agents, amine-based curing agents, imidazole-based curing agents, and phosphine-based curing agents. When the curing agent contains phenolic hydroxyl groups, acid anhydrides, amines, or imidazoles, it is easy to exhibit flux activity for suppressing the formation of an oxide film at the connection portion, and it is easy to improve connection reliability and insulation reliability.

Examples of the phenolic resin-based curing agent include those having two or more phenolic hydroxyl groups in the molecule, and phenol novolac, cresol novolac, phenol aralkyl resin, and cresol naphthol formaldehyde polycondensate can be used. , triphenylmethane type multifunctional phenol, various multifunctional phenolic resins, etc. The phenolic resin-based curing agent can be used alone or in combination of two or more.

When the curable resin component contains an epoxy resin, the equivalent ratio of the phenolic resin-based curing agent to the epoxy resin (phenolic hydroxyl group/cyclo Oxygen group, molar ratio) may be 0.3-1.5, 0.4-1.0 or 0.5-1.0. When the equivalence ratio is 0.3 or more, there is a tendency to improve curability and adhesion. When the equivalence ratio is 1.5 or less, unreacted phenolic hydroxyl groups will not remain excessively, the water absorption rate will be suppressed, and the insulation reliability will be further improved. Propensity.

Examples of the acid anhydride curing agent include methylcyclohexanetetracarboxylic dianhydride, trimellitic anhydride, pyromellitic anhydride, benzophenone tetracarboxylic dianhydride, and ethylene glycol bis-trimellitic anhydride. The acid anhydride-based curing agents can be used alone or in combination of two or more.

When the curable resin component contains an epoxy resin, the equivalent ratio of the acid anhydride curing agent to the epoxy resin (acid anhydride group/epoxy group , molar ratio) can be 0.3-1.5, 0.4-1.0 or 0.5-1.0. When the equivalent ratio is 0.3 or more, there is a tendency to improve curability and adhesive force. When it is 1.5 or less, unreacted acid anhydride does not remain in excess, the water absorption rate is suppressed low, and the insulation reliability tends to be further improved. .

As an amine curing agent, dicyandiamide is mentioned, for example.

When the curable resin component contains an epoxy resin, the equivalent ratio of the amine-based curing agent to the epoxy resin (amine/epoxy group, Molar ratio) can be 0.3-1.5, 0.4-1.0 or 0.5-1.0. When the equivalent ratio is 0.3 or more, the curability tends to be improved and the adhesive force tends to be improved, and when it is 1.5 or less, the unreacted amine does not remain excessively, and the insulation reliability tends to be further improved.

Examples of imidazole-based curing agents include 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1 -Cyanoethyl-2-undecylimidazole, 1-cyano-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole trimellitate, 1-cyanoethyl Base-2-phenylimidazolium trimellitate, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-di Amino-6-[2'-undecylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-ethyl-4'-methylimidazole Base-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine isocyanuric acid Adducts, 2-phenylimidazole isocyanuric acid adducts, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, Adducts of epoxy resins and imidazoles. Among them, the imidazole-based curing agent may be 1-cyanoethyl-2-undecylimidazole, 1-cyano-2-phenyl Imidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6- [2'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl-(1') ]-ethyl-s-triazine, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine isocyanuric acid adduct, 2- Phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole and 2-phenyl-4-methyl-5-hydroxymethylimidazole. The imidazole-based curing agents can be used alone or in combination of two or more. Furthermore, these can also be used as latent curing agents for microencapsulation.

The content of the imidazole-based curing agent may be 0.1-20 parts by mass, 0.1-10 parts by mass, 0.1-5 parts by mass, or 0.5-5 parts by mass relative to 100 parts by mass of the curable resin component. When the content of the imidazole-based curing agent is 0.1 parts by mass or more, the curability tends to be improved, and when it is 20 parts by mass or less, the adhesive composition does not harden until the metal joint is formed, and poor connection tends to be less likely to occur.

Examples of phosphine-based curing agents include triphenylphosphine, tetraphenylphosphonium tetraphenylborate, tetraphenylphosphonium tetrakis(4-methylphenyl)borate, and tetraphenylphosphonium tetrakis(4-fluorophenyl)borate. Phosphonium.

The content of the phosphine-based curing agent may be 0.1 to 10 parts by mass or 0.1 to 5 parts by mass relative to 100 parts by mass of the curable resin component. When the content of the phosphine-based curing agent is 0.1 parts by mass or more, curability tends to improve, and when it is 10 parts by mass or less, the adhesive for semiconductors does not harden until metal bonding is formed, and poor connection tends to be less likely to occur.

The phenolic resin-based curing agent, acid anhydride-based curing agent, and amine-based curing agent can be used alone or in combination of two or more. The imidazole-based curing agent and the phosphine-based curing agent can be used alone, or together with a phenolic resin-based curing agent, an acid anhydride-based curing agent, or an amine-based curing agent.

As the curing agent, from the viewpoint of excellent curability, a phenolic resin-based curing agent and an imidazole-based curing agent can be used in combination, an acid anhydride-based curing agent and an imidazole-based curing agent can be used in combination, and an amine-based curing agent and an imidazole-based curing agent can be used in combination , or use imidazole curing agent alone. The productivity is improved when connecting in a short time, so an imidazole-based curing agent with excellent fast curing properties can be used alone. In this case, since volatile components such as low-molecular components can be suppressed during curing in a short time, generation of voids can also be easily suppressed.

The content of the curing agent may be 0.1 to 20 parts by mass or 0.1 to 10 parts by mass relative to 100 parts by mass of the curable resin component.

((c) thermoplastic resin)

Examples of thermoplastic resins include phenoxy resins, polyimide resins, polyamide resins, polycarbodiimide resins, cyanate resins, (meth)acrylic resins, polyester resins, polyethylene resins, polyester resins, Ethersulfone resin, polyetherimide resin, polyvinyl acetal resin, urethane resin, acrylate rubber, etc. Examples of thermoplastic resins include phenoxy resins, polyimide resins, (meth)acrylic resins, acrylate rubbers, cyanate resins, polycarbonate resins, etc., from the viewpoint of excellent heat resistance and film formability. Examples of imide resins include phenoxy resins, polyimide resins, (meth)acrylic resins, and acrylate rubbers. The thermoplastic resins can be used alone or in combination of two or more.

As a phenoxy resin, ZX1356-2 and FX-293 by NIPPON STEEL Chemical & Material Co., Ltd. are mentioned, for example. As the urethane resin, T-8175N manufactured by DIC Covestro Polymer Ltd., which is polyurethane, can be used, for example. As the (meth)acrylic resin, for example, acrylic acid, which is a block copolymer of at least one compound of (meth)acrylate compounds such as (meth)acrylic acid and (meth)acrylate such as methyl (meth)acrylate, can be used. Department of block copolymers. As the acrylic block copolymer, for example, LA4285, LA2330, and LA2140 (all manufactured by KURARAY CO., LTD.), which are block copolymers of methyl methacrylate and butyl acrylate, can be used. The thermoplastic resin may be a phenoxy resin having a structure (a structure with many aromatic rings) that easily adopts a crystal structure from the viewpoint of better heat dissipation.

The thermoplastic resin may have a glass transition temperature (Tg) of 120° C. or lower, 100° C. or lower, or 85° C. or lower from the viewpoint of excellent adhesion to substrates and chips. Since the adhesive for semiconductors contains a thermoplastic resin with a Tg of 120°C or less, the curing reaction can be suppressed, so it is easy to embed bumps formed on semiconductor chips, electrodes and wiring patterns formed on substrates, and other irregularities, so air bubbles are less likely to remain. , there is a tendency to easily suppress the generation of voids. Furthermore, when the adhesive for a semiconductor contains a thermoplastic resin having a Tg of room temperature (25° C.) or higher, it becomes easy to form the adhesive for a semiconductor into a thin film or a film.

In this specification, the Tg of a thermoplastic resin is measured using differential scanning calorimetry (DSC, DSC-7 type manufactured by PerkinElmer Co., Ltd.) under the conditions of a sample amount of 10 mg, a temperature increase rate of 10°C/min, and a measurement atmosphere: air Tg at the time of measurement.

The weight average molecular weight of the thermoplastic resin may be 10,000 or more, 30,000 or more, 40,000 or more, or 50,000 or more from the viewpoint of excellent film-forming properties of the adhesive for semiconductors. From the viewpoint of excellent film processability of the adhesive for semiconductors, the weight average molecular weight of the thermoplastic resin may be 1,000,000 or less or 500,000 or less.

In the present specification, the weight average molecular weight refers to the weight average molecular weight when measured in terms of polystyrene using high-speed liquid chromatography (C-R4A manufactured by Shimadzu Corporation).

When the curable resin component contains an epoxy resin and a thermoplastic resin, the content of the epoxy resin may be 1 part by mass or more, 5 parts by mass or more, or 10 parts by mass or more, and may be 500 parts by mass relative to 100 parts by mass of the thermoplastic resin. Parts by mass or less, 400 parts by mass or less, or 300 parts by mass or less. The content of the epoxy resin may be 1 to 500 parts by mass, 5 to 400 parts by mass, or 10 to 300 parts by mass relative to 100 parts by mass of the thermoplastic resin. When the content of the epoxy resin is within these ranges, the adhesive for semiconductors has sufficient curability and is excellent in adhesive force, and it is easy to form the adhesive for semiconductors into a film or film.

The content of the thermoplastic resin may be at least 0.1 parts by mass, at least 1 part by mass, or at least 10 parts by mass, and may be at most 50 parts by mass or at most 40 parts by mass based on 100 parts by mass of the curable resin component. Content of a thermoplastic resin can be 0.1-50 mass parts, 1-50 mass parts, or 10-40 mass parts with respect to 100 mass parts of curable resin components.

Based on the total amount of the adhesive for semiconductors, the content of the curable resin component may be 10% by mass or more, or 30% by mass or more, and may be 70% by mass or less, or 50% by mass or less. Based on the total amount of the adhesive for semiconductors, the content of the curable resin component may be 10-70% by mass, 10-50% by mass or 30-50% by mass.

(Flux)

The adhesive for semiconductors according to the present embodiment may further contain a flux (that is, a flux activator exhibiting flux activity (activity to remove oxides, impurities, etc.)). Examples of the flux include nitrogen-containing compounds (imidazoles, amines, and the like) having unshared electron pairs, carboxylic acids, phenols, alcohols, and the like.

The flux may contain an organic acid that reacts with the epoxy resin from the viewpoint of exhibiting stronger flux activity than alcohols and easily improving connectivity.

When the curable resin component contains epoxy resin, it reacts with epoxy resin and does not exist in a free state in the cured product of the semiconductor adhesive, so it can prevent the reduction of insulation reliability, so organic acid can be contained, Carboxylic acid may also be contained.

Examples of the carboxylic acid include ethanoic acid, propionic acid, butyric acid, pentanoic acid, hexanoic acid, heptanoic acid, caprylic acid, nonanoic acid, capric acid, dodecanoic acid, myristic acid, hexadecanoic acid, Heptadecanoic acid, octadecanoic acid and other fatty saturated carboxylic acids; oleic acid, linoleic acid, linolenic acid, arachidonic acid, docosahexaenoic acid, eicosapentaenoic acid and other fatty unsaturated Carboxylic acid; oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid and other aliphatic dicarboxylic acids; benzoic acid (benzoic acid), phthalic acid, isophthalic acid, terephthalic acid, trimene Aromatic carboxylic acids such as triacids, trimesic acid, pyrellitic acid, pyromellitic acid, pentanecarboxylic acid, benzoic acid (mesic acid); maleic acid and fumaric acid. Moreover, lactic acid, malic acid, citric acid, salicylic acid etc. are mentioned as a carboxylic acid which has a hydroxyl group.

The carboxylic acid may be a dicarboxylic acid. Since dicarboxylic acids are relatively less volatile than monocarboxylic acids, there is a tendency that voids can be suppressed. In addition, dicarboxylic acids are less likely to react at low temperatures (temperatures below joining, for example, 100° C. or less) in film formation, lamination, preheating, etc., compared with tricarboxylic acids, so the viscosity does not become too large, and there is a possibility of Suppresses the tendency to connect poorly.

The carboxylic acid may have one or more alkyl groups at the 2- or 3-position from the carboxyl group. Examples of the carboxylic acid having such an alkyl group include 2-methylglutaric acid, 3-methylglutaric acid, and the like.

The content of the flux may be 0.5 parts by mass or more, 1 part by mass or more, or 1.5 parts by mass or more with respect to 100 parts by mass of the adhesive for semiconductors. The content of the flux may be 10 parts by mass or less or 5 parts by mass or less with respect to 100 parts by mass of the adhesive for semiconductors. The content of the flux may be 0.5 to 10 parts by mass or 0.5 to 5 parts by mass relative to 100 parts by mass of the adhesive for semiconductors.

(inorganic filler)

The adhesive for semiconductors of this embodiment contains an inorganic filler. Based on the total amount of the binder for semiconductors, the content of the inorganic filler is 60 to 95% by mass. When the content of the inorganic filler is within the above range, excellent heat dissipation properties can be imparted to the adhesive for semiconductors.

Examples of the inorganic filler include aluminum oxide (Al ₂ O ₃ ), magnesium oxide, silicon carbide, boron nitride, diamond, and aluminum nitride. From the viewpoint of thermal conductivity of the adhesive for semiconductors, the inorganic filler may contain at least one selected from the group consisting of alumina, silicon carbide, boron nitride, diamond, and aluminum nitride.

When the inorganic filler is particles containing alumina (hereinafter also referred to as "alumina filler"), the alumina may be α-alumina. The alumina filler may have a purity of 99.0% by mass or more, 99.5% by mass or more, or 99.9% by mass or more from the viewpoint of excellent heat dissipation of the adhesive for semiconductors. The purity of the alumina filler may be substantially composed of alumina (100% by mass of the alumina filler is substantially alumina).

The shape of the alumina filler is not particularly limited, and examples thereof include spherical, substantially spherical, polyhedral, needle-shaped, and plate-shaped. Among them, from the viewpoint of excellent heat dissipation of the adhesive for semiconductors, it may be spherical or polyhedral, and may be polyhedral. In addition, in this specification, a "polyhedron" means a solid having a plurality of planes as constituent parts of the surface. A plurality of planes may intersect each other via a curved surface (it may be a shape with rounded corners). A polyhedron can have, for example, 4 to 100 planes as a component of a surface.

The reason why the heat dissipation performance of the adhesive for semiconductors is excellent by using polyhedral alumina as the alumina filler is not necessarily clear, but the inventors of the present invention think that since the alumina filler is polyhedral, the fillers contact each other on the surface, and the heat transfer area becomes large, so that Heat transfer is improved.

The average particle size of the inorganic filler may be 20 μm or less, 15 μm or less, or 10 μm or less from the viewpoint of improving film-forming properties when the semiconductor adhesive is made into a film. From the viewpoint of the dispersibility of the inorganic filler, the average particle diameter of the inorganic filler may be 0.1 μm or more, 0.5 μm or more, or 1 μm or more.

In this specification, "average particle diameter" refers to the particle diameter at a point corresponding to 50% of the volume when the cumulative frequency distribution curve based on the particle diameter is calculated with the total volume of the particles as 100%. The particle size distribution measuring device of the method can be used for measurement.

From the viewpoint of further improving visibility, dispersibility, and adhesive force, the alumina filler may be one in which the surface of alumina is treated. Examples of surface treatment agents include glycidyl-based (epoxy) compounds, amine-based compounds, phenyl-based compounds, phenylamino-based compounds, (meth)acrylic-based compounds (for example, compounds having a compound having a structure represented by the formula (1), a vinyl compound having a structure represented by the following general formula (2), and the like.

[R ¹¹ represents a hydrogen atom or an alkyl group, and R ¹² represents an alkylene group. ]

Examples of fillers surface-treated by a compound having a structure represented by formula (1) include acrylic surface-treated fillers in which R ¹¹ is a hydrogen atom, methacrylic surface-treated fillers in which R ¹¹ is a methyl group, and R ¹¹ is an ethyl group. Ethyl acrylic acid surface treatment filler, etc. From the viewpoint of reactivity with the resin contained in the adhesive for semiconductors and the surface of the semiconductor substrate, and bond formation, R ¹¹ may be a hydrogen atom or a methyl group as a substituent that is not bulky. The surface treated filler may be an acrylic surface treated filler or a methacrylic surface treated filler. The alkylene group of ^R12 is not particularly limited, but may be a group with a high weight average molecular weight from the viewpoint of reducing volatile components.

[R ²¹ , R ²² and R ²³ each independently represent a hydrogen atom or an alkyl group, and R ²⁴ represents an alkylene group. ]

From the viewpoint of not lowering the reactivity, R ²¹ , R ²² and R ²³ may be small-sized substituents. In addition, it may be a substituent that improves the reactivity of the vinyl group in formula (2). R ²⁴ is not particularly limited, but may be a group with a high weight average molecular weight from the viewpoint of less volatilization and reduction of voids. In addition, R ²¹ , R ²² , R ²³ and R ²⁴ can also be selected according to the difficulty of surface treatment. For example, R ²¹ , R ²² and R ²³ may also be a hydrogen atom or a methyl group.

As the surface treatment agent, silane compounds such as epoxy-based silane, amino-based silane, (meth)acrylic-based silane, and vinyl-based silane can be used in view of the easiness of surface treatment. In addition, the alumina filler may be one in which the surface of alumina is silane-treated from the viewpoint of better transparency of the adhesive for semiconductors. The surface treating agent may be a glycidyl-based, phenylamino-based, (meth)acrylic acid, or vinyl-based silane compound from the viewpoint of excellent dispersibility, fluidity, and adhesive force. As the surface treatment agent, vinyl-based, phenylamino-based, or (meth)acrylic-based silane compounds may be used from the viewpoint of excellent storage stability.

An inorganic filler can be used individually by 1 type, or can use different 2 or more types together. The inorganic fillers used together may be, for example, two or more different kinds of inorganic fillers such as alumina fillers and silicon carbide used together. In addition, the inorganic fillers used together may be two or more types of the same type of inorganic fillers that differ in shape, average particle diameter, surface treatment, and the like.

From the standpoint of better heat dissipation, the inorganic fillers used at the same time may be two or more of the same type of inorganic filler, two or more of alumina fillers, two or more polyhedral alumina fillers, or two or more of average particle size fillers. Polyhedral alumina with different diameters.

In the case of using two or more inorganic fillers, from the viewpoint of better heat dissipation, the inorganic filler may have a plurality of peaks in the volume-based particle size distribution, and may be between 0.1 to 4.5 μm and 5 μm. Fillers with peaks in the respective ranges of ~20 μm. In addition, in this specification, a "peak" means the maximum value of the number frequency in the volume-based particle size distribution.

From the viewpoint of better heat dissipation, one of the peaks (first peak) may be 5 to 15 μm, 5 to 10 μm, or 5 to 8 μm. From the viewpoint of better heat dissipation, one of the peaks (second peak) may be 0.1 to 3.0 μm, 0.1 to 2.0 μm, or 0.1 to 1.5 μm.

From the viewpoint of better heat dissipation, the difference between the peak positions of the first peak and the second peak may be 4 μm or more or 5 μm or more, and may be 10 μm or less, 8 μm or less, or 7 μm or less. The difference between the peak positions of the first peak and the second peak may be 4-10 μm, 4-8 μm, or 5-7 μm.

An inorganic filler having a plurality of peaks in the volume-based particle size distribution can be obtained by using together two or more types of inorganic fillers different in mode diameter or average particle diameter. The inorganic filler used at the same time can be, for example, an inorganic filler with a mode diameter or an average particle diameter of 5 to 20 μm and an inorganic filler with a mode diameter or an average particle diameter of 0.1 to 4.5 μm.

From the viewpoint of better heat dissipation, the adhesive for semiconductors may contain a first inorganic filler having a mode diameter or average particle diameter of 5 to 20 μm and a second inorganic filler having a mode diameter or average particle diameter of 0.1 to 4.5 μm. The mode diameter or average particle diameter of the first inorganic filler may be 5-15 μm, 5-10 μm, or 5-8 μm. The mode diameter or average particle diameter of the second inorganic filler may be 0.1-3.0 μm, 0.1-2.0 μm, or 0.1-1.5 μm.

From the standpoint of better heat dissipation, the adhesive for semiconductors can be formulated with the first polyhedral alumina having an average particle size _r1 of 5 to 20 μm and the second polyhedral aluminum oxide having an average particle size _r2 of 0.1 to 4.5 μm. Bulk alumina. The average particle diameter r ₁ of the first polyhedral alumina may be 5-15 μm, 5-10 μm or 5-8 μm. The average particle diameter r ₂ of the second polyhedral alumina may be 0.1-3.0 μm, 0.1-2.0 μm or 0.1-1.5 μm.

From the standpoint of better heat dissipation, the difference (r ₁ -r ₂ ) between the average particle diameter r ₁ of the first polyhedral alumina and the average particle diameter r ₂ of the second polyhedral alumina may be 4 to 10μm, 4~8μm or 5~7μm.

Regarding the blending amount of the first polyhedral alumina and the second polyhedral alumina, the second polyhedral alumina can be 10 to 70 parts by mass, 10 to 70 parts by mass relative to 100 parts by mass of the first polyhedral alumina. 50 parts by mass or 10 to 30 parts by mass.

From the viewpoint of better heat dissipation, based on the total amount of the adhesive for semiconductors, the content of the first polyhedral alumina in the adhesive for semiconductors may be 60 mass % or more or 70 mass % or more, and may be It is 90 mass % or less or 85 mass % or less. Based on the total amount of the adhesive for semiconductors, the content of the first polyhedral alumina in the adhesive for semiconductors may be 60-90% by mass or 70-85% by mass.

From the standpoint of better heat dissipation, the content of the second polyhedral alumina in the semiconductor adhesive may be 10 mass % or more or 15 mass % or more based on the total amount of the semiconductor adhesive, and may be It is 30 mass % or less or 20 mass % or less. Based on the total amount of the adhesive for semiconductors, the content of the second polyhedral alumina in the adhesive for semiconductors may be 10-30% by mass or 15-20% by mass.

From the viewpoint of better heat dissipation, the content of the inorganic filler may be 75% by mass or more or 85% by mass or more based on the total amount of the binder for semiconductors. In addition, when an inorganic filler is two or more types of inorganic fillers, content of an inorganic filler means the total amount of all inorganic fillers.

When the inorganic filler is an alumina filler, the content of the alumina filler may be 75% by mass or more or 85% by mass or more based on the total amount of the adhesive for semiconductors from the viewpoint of better heat dissipation. In addition, when the inorganic filler is two or more kinds of alumina fillers, the content of the alumina filler means the total amount of all the alumina fillers.

When the inorganic filler is a mixture of two or more alumina fillers having different average particle diameters or mode diameters, the average particle diameter or The content of the alumina filler having the largest mode diameter may be 60 to 90% by mass or 70 to 85% by mass.

(other)

The semiconductor adhesive of this embodiment may also contain additives such as organic fillers (resin fillers), antioxidants, silane coupling agents (excluding compounds suitable for flux), titanium coupling agents, and leveling agents. These additives can be used alone or in combination of two or more. What is necessary is just to adjust content of these additives suitably so that the effect of each additive may be exhibited.

As a material of the organic filler, polyurethane, polyimide, or the like can be used. Compared with inorganic fillers, resin fillers can impart flexibility at high temperatures such as 260° C., and thus are effective in improving film formability.

(Thermal conductivity)

The thermal conductivity of the adhesive for semiconductors according to this embodiment after curing is 1.5 W/mK or more. By setting the thermal conductivity of the adhesive for semiconductors after curing to 1.5 W/mK or more, it is possible to provide an adhesive for semiconductors excellent in heat dissipation.

From the standpoint of better heat dissipation, the thermal conductivity of adhesives for semiconductors after curing can be 2.0 W/mK or higher, 2.5 W/mK or higher, 3.0 W/mK or higher, 3.5 W/mK or higher, or 4.0 W/mK or higher .

The thermal conductivity of the semiconductor adhesive after curing can be calculated by measuring the thermal diffusivity by the laser flash method (Xe-flash method), and multiplying the specific heat and density by the thermal diffusivity. Specifically, it can be calculated by The thermal conductivity was obtained by the documented method.

The adhesive for semiconductors can be cured by heating at 240° C. for 1 hour. Specifically, the adhesive for semiconductors after curing can be obtained by the method described in Examples described later.

The adhesive for semiconductors according to the present embodiment can be formed into a thin film or a film. The thickness of the film-like or film-like adhesive for semiconductors (film-like adhesive) may be, for example, 100 μm or less, 80 μm or less, or 50 μm or less. The lower limit of the thickness of the film-form adhesive is not particularly limited, and may be 1 μm or more or 5 μm or more.

<Preparation method of adhesive for semiconductor>

A film-like or film-like adhesive for semiconductors can be obtained by the following method. First, the resin varnish is prepared by adding the curable resin component, flux, inorganic filler, and other components described above to an organic solvent, and then dissolving or dispersing them by stirring, kneading, or the like. Then, on the substrate film subjected to mold release treatment, a resin varnish is applied by using a knife coater, a roll coater, an applicator, a die coater, a comma coater, or the like, and then heated Reduces organic solvents and forms an adhesive for semiconductors on a base film. In addition, before reducing the organic solvent by heating, the resin varnish may be spin-coated on a wafer or the like to form a film, and then the adhesive for semiconductors may be formed on the wafer by a method of drying the solvent.

The base film is not particularly limited as long as it is a film with heat resistance that can withstand the heating conditions when the organic solvent is volatilized, and polyester film, polypropylene film, polyethylene terephthalate film, etc. Ester film, polyimide film, polyetherimide film, polyether naphthalate film, methylpentene film, etc. The base film is not limited to a single-layer film composed of one of these films, but may be a multilayer film composed of two or more films.

As conditions for volatilizing the organic solvent from the applied resin varnish, specifically, heating at 50 to 200° C. for 0.1 to 90 minutes can be performed. As long as there is no influence on voids after mounting, viscosity adjustment, etc., the condition that the organic solvent volatilizes to 1.5% or less may be used.

<Semiconductor device>

A semiconductor device manufactured using the adhesive for semiconductors according to this embodiment will be described. The semiconductor device according to this embodiment includes a connection structure in which connection portions of a semiconductor chip and a printed circuit board are electrically connected to each other and/or a connection structure in which connection portions of a plurality of semiconductor chips are electrically connected to each other, And the sealing material which seals at least a part of a connection part, The sealing material contains the hardened|cured material of the adhesive agent for semiconductors concerning this embodiment. The connection portion in the semiconductor device may be any of metal bonding between bumps and wirings and metal bonding between bumps. In the semiconductor device according to the present embodiment, for example, flip-chip connection in which electrical connection is achieved through an adhesive for a semiconductor can be used.

FIG. 1 is a schematic cross-sectional view showing an embodiment of a semiconductor device (a COB connection method between a semiconductor chip and a substrate). As shown in FIG. 1( a), the semiconductor device 100 has a semiconductor chip 10 and a substrate (circuit wiring board) 20 facing each other, wiring 15 arranged on the surfaces of the semiconductor chip 10 and the substrate 20 facing each other, The connection bump 30 which connects the wiring 15 of the semiconductor chip 10 and the substrate 20 to each other, and the sealing material 40 which fills the gap between the semiconductor chip 10 and the substrate 20 without any gap. The semiconductor chip 10 and the substrate 20 are flip-chip connected through the wiring 15 and the connection bump 30 . The wiring 15 and the connection bump 30 are sealed by the sealing material 40 and isolated from the external environment. The sealing material 40 contains the hardened|cured material of the adhesive agent for semiconductors concerning this embodiment.

As shown in FIG. 1( b ), the semiconductor device 200 has a semiconductor chip 10 and a substrate 20 facing each other, bumps 32 respectively arranged on the surfaces of the semiconductor chip 10 and the substrate 20 facing each other, and the bumps 32 filled without gaps. The sealing material 40 in the gap between the semiconductor chip 10 and the substrate 20 . The semiconductor chip 10 and the substrate 20 are flip-chip connected to each other by opposing bumps 32 . The bump 32 is sealed by a sealing material 40 and isolated from the external environment.

2 is a schematic cross-sectional view showing another embodiment (COC-type connection method between semiconductor chips) of the semiconductor device. As shown in FIG. 2( a ), the semiconductor device 300 is the same as the semiconductor device 100 except that the two semiconductor chips 10 are flip-chip connected through the wiring 15 and the connection bump 30 . As shown in FIG. 2( b ), the semiconductor device 400 is the same as the semiconductor device 200 except that the two semiconductor chips 10 are flip-chip connected via the bumps 32 .

The semiconductor chip 10 is not particularly limited, and various semiconductors such as element semiconductors made of the same type of elements such as silicon and germanium, and compound semiconductors such as gallium arsenide and indium phosphide can be used.

As the substrate 20, it is not particularly limited as long as it is a wiring circuit board, and etching removal materials made of glass epoxy, polyimide, polyester, ceramic, epoxy, bismaleimide triazine, etc. can be used. A circuit board in which wiring (wiring pattern) is formed on unnecessary parts of a metal layer formed on the surface of an insulating substrate whose main component is polyimide, or a circuit board in which wiring (wiring patterns) is formed on the surface of the above-mentioned insulating substrate by metal plating or the like. A circuit board with wiring (wiring pattern) and a circuit board with wiring (wiring pattern) formed by printing a conductive substance on the surface of the above-mentioned insulating substrate, and the like.

Connection parts such as wiring 15 and bump 32 contain gold, silver, copper, solder (main components such as tin silver, tin lead, tin bismuth, tin copper), nickel, tin, lead, etc. as main components, and may contain more a metal.

A metal layer mainly composed of gold, silver, copper, solder (main components such as tin silver, tin lead, tin bismuth, tin copper), tin, nickel, etc. may be formed on the surface of the wiring (wiring pattern). . The metal layer may be composed of only a single component or may be composed of a plurality of components. Furthermore, a structure in which a plurality of metal layers are laminated may also be adopted. The metal layer can be copper, solder since it is cheap and commonly used, but requires flux activity due to oxides or impurities.

As the material of conductive protrusions called bumps, gold, silver, copper, solder (main components such as tin-silver, tin-lead, tin-bismuth, tin-copper), tin, nickel, etc. are used as main components. , may consist of only a single component, or may consist of a plurality of components. Furthermore, a structure in which these metals are laminated may also be used. Bumps can also be formed on semiconductor chips or substrates. Bumps can be copper, solder since they are cheap and commonly used, but require flux activity due to oxides or impurities.

In addition, it is also possible to laminate semiconductor devices (packages) as shown in FIG. 1 or FIG. Tin, nickel and other electrical connections. Copper, solder can be used for connection since it is cheap and commonly used, but flux activity is required due to oxides or impurities. For example, as seen in TSV technology, it is also possible to perform flip-chip connection or stacking by interposing semiconductor adhesives between semiconductor chips, forming holes penetrating the semiconductor chips, and connecting to electrodes on the pattern surface.

3 is a schematic cross-sectional view showing another embodiment (semiconductor chip stacked type (TSV)) of the semiconductor device. In semiconductor device 500 shown in FIG. flip-chip connection. The gap between the semiconductor chip 10 and the interposer 50 is filled with the sealing material 40 without gaps. On the surface of the above-mentioned semiconductor chip 10 opposite to the interposer 50 , the semiconductor chip 10 is repeatedly laminated via the wiring 15 , the connection bump 30 and the sealing material 40 . The wirings 15 on the front and rear pattern surfaces of the semiconductor chip 10 are connected to each other by the through electrodes 34 filled in the holes penetrating the inside of the semiconductor chip 10 . In addition, copper, aluminum, or the like can be used as the material of the penetration electrode 34 .

With this TSV technology, it is also possible to obtain signals from the backside of semiconductor chips, which are not normally used. Furthermore, since the penetrating electrodes 34 vertically pass through the semiconductor chips 10 , the distance between opposing semiconductor chips 10 or between the semiconductor chips 10 and the interposer 50 can be shortened, enabling flexible connection. The semiconductor adhesive according to the present embodiment can be applied as a sealing material between opposing semiconductor chips 10 or between the semiconductor chip 10 and the interposer 50 in such a TSV technology.

In addition, in a bump forming method with a high degree of freedom such as area bump chip technology, the semiconductor chip can be directly mounted on the motherboard as it is without interposing an interposer. The adhesive for semiconductors according to this embodiment can also be applied to the case where such a semiconductor chip is directly mounted on a motherboard. In addition, the adhesive for semiconductors according to the present embodiment can be applied also when sealing the gap between the substrates when laminating two printed circuit boards.

5 is a schematic cross-sectional view showing another embodiment of the semiconductor device (a COB-type connection method between a semiconductor chip and a substrate). In the semiconductor device 600 shown in FIG. 10 are connected to each other via a sealing material 40 . The wiring 15 of the semiconductor chip 10 and the wiring 15 of the substrate 60 are electrically connected by connection bumps (solder bumps) 30 . On the surface of the substrate 60 on which the wiring 15 is formed, the solder resist layer 70 is arranged except for the formation position of the connection bump 30 . The semiconductor chip 10 may have through electrodes.

<Manufacturing method of semiconductor device>

In the method of manufacturing a semiconductor device according to this embodiment, the semiconductor device includes a connection structure in which connection parts of the semiconductor chip and the printed circuit board are electrically connected to each other and/or the connection parts of the plurality of semiconductor chips A connection structure electrically connected to each other. The method of manufacturing the semiconductor device includes a step of sealing at least a part of the connection portion with the adhesive for a semiconductor according to the present embodiment.

The above steps can be performed by connecting a semiconductor chip and a printed circuit board or a plurality of semiconductor chips to each other using the adhesive for semiconductors according to this embodiment. In this case, the method of manufacturing a semiconductor device according to this embodiment may include, for example, connecting the semiconductor chip and the printed circuit board to each other through an adhesive for semiconductors, and connecting the semiconductor chip and the printed circuit board to each other. A step of electrically connecting connection portions and/or a step of connecting a plurality of semiconductor chips to each other through an adhesive for semiconductors, and electrically connecting connection portions of the plurality of semiconductor chips to each other.

In the method of manufacturing a semiconductor device according to this embodiment, the connecting portions can be connected to each other by metal bonding. That is, the connection portions of the semiconductor chip and the printed circuit board may be connected to each other by metal bonding, or the connection portions of the plurality of semiconductor chips may be connected to each other by metal bonding.

As an example of a method of manufacturing a semiconductor device according to this embodiment, a method of manufacturing a semiconductor device 500 shown in FIG. 3 will be described. In the semiconductor device 500, the wiring (copper wiring) 15 formed on the interposer 50 connects the bump (solder bump) 30 and the wiring (copper pillar, post )) 15, whereby the semiconductor chip 10 and the interposer 50 are flip-chip connected. The gap between the semiconductor chip 10 and the interposer 50 is filled with the sealing material 40 without gaps. On the surface of the above-mentioned semiconductor chip 10 opposite to the interposer 50 , the semiconductor chip 10 is repeatedly laminated via the wiring 15 , the connection bump 30 and the sealing material 40 . The wirings 15 on the front and rear pattern surfaces of the semiconductor chip 10 are connected to each other by the through electrodes 34 filled in the holes penetrating the inside of the semiconductor chip 10 .

FIG. 4 is a diagram for explaining an example of a method of manufacturing the semiconductor device shown in FIG. 3 . FIG. 4( a ) shows a step of pressure-bonding the laminated chip provided with the semiconductor adhesive on the main surface of the semiconductor chip and another semiconductor chip through the semiconductor adhesive. The laminated chip (stacked semiconductor chip) 700 includes a semiconductor chip 10 and an adhesive 42 for semiconductors provided on the main surface of the semiconductor chip 10, and the semiconductor chip 10 is provided with a penetrating hole filled in a hole penetrating the inside of the semiconductor chip 10. The electrodes 34 , the wiring 15 arranged on one surface of the semiconductor chip 10 , and the connection bumps 30 arranged on the wiring 15 . The semiconductor adhesive 42 is provided so as to bury the wiring 15 and the connection bump 30 , but may cover at least a part of the surface of the semiconductor chip 10 , the wiring 15 and the connection bump 30 .

In the stacked chip 700, the semiconductor chip 10 can be separated by dicing after applying the semiconductor adhesive 42 on the semiconductor wafer having the wiring 15 and the connection bump 30, or attaching the semiconductor adhesive 42 in a film form. sliced to make. Attaching of the film-like adhesive for semiconductors can be performed by heat press, roll lamination, vacuum lamination, or the like.

The pressure bonding of the laminated chip 700 to another semiconductor chip can be performed, for example, by aligning the connection bumps 30 of the laminated chip 700 with the through-electrodes 34 filled in the holes penetrating the inside of another semiconductor chip 10 . Standard, while heating the laminated chip 700 and the semiconductor chip 10 at a temperature above the melting point of the connection bump 30, use the pressure bonding tool 90 to perform pressure bonding (in the case of using solder for the connection portion, the temperature applied to the solder portion can be 240 ℃ above). Thereby, the laminated chip 700 and the semiconductor chip 10 can be connected, and the connection portion can be sealed by the cured product of the semiconductor adhesive.

The connection load depends on the number of bumps, but it can be set in consideration of absorption of bump height deviation, control of bump deformation amount, and the like. From the viewpoint of improving productivity, the connection time may be short. The connection time may be a time when the solder is melted to remove oxide films, surface impurities, and the like, and a metal joint can be formed at the connection portion. The short connection time (crimping time) means that the time (for example, time when solder is used) for applying a temperature of 240° C. or higher to the connection portion during connection formation (main crimping) is 10 seconds or less. The connection time can be under 5 seconds or under 3 seconds. The same method can also be applied to the connection between the interposer 50 having the wiring 15 and the laminated chip 700 .

By repeating the above steps, the semiconductor device 500 shown in FIG. 4( b ) can be manufactured. In addition, the semiconductor device 500 may be heat-treated in a reflow furnace after repeatedly aligning and laminating (temporarily fixing) the laminated chip 700 and the semiconductor chip 10 to obtain a temporarily fixed multilayer laminate. Solder bumps are manufactured by melting and connecting semiconductor chips together. Since the temporary fixing does not significantly require the necessity of forming a metal joint, compared with the above-mentioned formal crimping, it can also be lower load, shorter time, and lower temperature, resulting in advantages such as improved productivity and prevention of deterioration of the connection part. After connecting the semiconductor chip and the substrate, heat treatment may be performed in an oven or the like to harden the adhesive for semiconductors. The heating temperature may be a temperature at which the adhesive for semiconductor sealing is cured and completely cured. What is necessary is just to set heating temperature and heating time suitably.

Example

Hereinafter, although an Example demonstrates this invention, this invention is not limited to these Examples.

<Production of adhesives for semiconductors>

The compounds used in the production of the adhesive for semiconductors are shown below.

(curable resin component)

((a) epoxy resin)

・Multifunctional solid epoxy resin containing triphenolmethane skeleton (manufactured by Japan Epoxy Resins Co. Ltd., product name "EP1032H60")

・Bisphenol F type liquid epoxy resin (manufactured by Japan Epoxy Resins Co. Ltd., product name "YL983U")

· Flexible epoxy resin (manufactured by Japan Epoxy Resins Co. Ltd., product name "YL7175")

((b) curing agent)

2,4-Diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine isocyanuric acid adduct (manufactured by SHIKOKUCHEMICALS CORPORATION., product name "2MAOK-PW ")

((c) thermoplastic resin)

Phenoxy resin (manufactured by NIPPON STEEL Chemical & Material Co., Ltd., product name "ZX1356-2", Tg: about 71°C, Mw: about 63000)

(inorganic filler)

・Polyhedral alumina 1 (Sumitomo Chemical Co., Ltd., AA-04, average particle size: 0.41 μm)

・Polyhedral alumina 2 (Sumitomo Chemical Co., Ltd., AA-07, average particle size: 0.83 μm)

・Polyhedral alumina 3 (Sumitomo Chemical Co., Ltd., AA-1.5, average particle size: 1.6 μm)

・Polyhedral alumina 4 (Sumitomo Chemical Co., Ltd., AA-3, average particle size: 3.7 μm)

・Polyhedral alumina 5 (Sumitomo Chemical Co., Ltd., AA-5, average particle size: 6.6 μm)

・Polyhedral alumina 6 (Sumitomo Chemical Co., Ltd., AA-10, average particle size: 14.5 μm)

・Silicon carbide 1 (TOMOE Engineering Co., Ltd., αSiC2500N, average particle size: 0.87 μm)

・Silicon carbide 2 (TOMOE Engineering Co., Ltd., βSiC2500N, average particle size: 0.82 μm)

· Boron nitride 1 (Momentive, PT132, average particle size: 5.1 μm)

· Boron nitride 2 (Momentive, AC6041, average particle size: 5.4 μm)

· Boron nitride 3 (Momentive, TECO20191251, average particle size: 4.5 μm)

・Diamond (Tomei Diamond, CMM2-4, average particle size: 2.4 μm)

(filler)

・Inorganic silica filler (Admatechs Co., Ltd., SE2050, average particle diameter: 500nm)

(Flux)

Glutaric acid (manufactured by Wako Pure Chemical Corporation, Wako special grade, melting point: about 95°C)

(Example 1)

Thermosetting resin (45 parts by mass of "EP1032H60", 15 parts by mass of "YL983U", 5 parts by mass of "YL7175"), 2 parts by mass of curing agent, inorganic filler (the amount recorded in Table 1, unit: mass % (for semiconductors) The total amount of the binder is based on)), 10 parts by mass of the organic filler, and 4 parts by mass of the flux were added to the organic solvent (cyclohexanone) so that the NV (non-volatile component concentration) became 55 mass%. Then, Φ1.0mm beads and Φ2.0mm beads of the same mass as the solid content were added, and stirred for 30 minutes with a bead mill (manufactured by Fritsch Japan Co., Ltd., planetary fine pulverizer P-7) . Then, 30 mass parts of phenoxy resins were added as a thermoplastic resin, and it stirred again for 30 minutes by the bead mill. Beads used in stirring were removed by filtration. The prepared varnish was coated with a small precision coating device (manufactured by Yasui Seiki Inc.), and dried (100°C/10 minutes) in a clean oven (manufactured by ESPEC CORP.) to obtain a film-like adhesive (for semiconductors) with a thickness of 400 μm. adhesive).

(Examples 2 to 21, Comparative Example 1)

Except having changed the kind and content of the inorganic filler as shown in Tables 1-4, it carried out similarly to Example 1, and obtained the film-form adhesive (adhesive for semiconductors). Moreover, the difference of the average particle diameter of Table 3 and 4 was calculated from the absolute value of the difference of the average particle diameter of the inorganic filler used together.

<Evaluation>

(1) Thermal conductivity measurement

The prepared film-like adhesive was cut into 1 cm×1 cm, and cured at 240° C. for 1 hour in a clean oven (manufactured by ESPEC CORP.) to obtain a cured product. Both surfaces of the obtained cured product were blackened with graphite spray, and the thermal diffusivity in the thickness direction was measured. Thermal diffusivity was measured by a laser flash method (Xe-flash method) (manufactured by NETZSCH, LFA447nanoflash). Pulse light irradiation was performed under conditions of a pulse width of 0.1 (ms) and an applied voltage of 236V. The measurement was performed at an atmosphere temperature of 25°C±1°C. Next, the value of the thermal conductivity was obtained by multiplying the specific heat and the density by the thermal diffusivity using the following formula (I). The results are shown in Tables 1-4.

λ=α×Cp×p...Formula (I)

[In formula (I), λ represents thermal conductivity (W/mK), α represents thermal diffusivity (m2/s), Cp represents specific heat (J/kg·K), and ρ represents density (g/cm ³ ). ]

In addition, using differential scanning calorimetry (DSC), specific heat (J/kg·K) was measured in the following procedure. The adhesive for semiconductors was weighed in an aluminum pan, and measured at 10°C/min at room temperature (25°C) to 60°C using a differential scanning calorimeter (manufactured by PerkinElmer Japan Co., Ltd., Pyris 1). Use sapphire as a reference. The specific heat at 25° C. of the sample was calculated using the known specific heat of sapphire.

Density (g/cm ³ ) was measured at a water temperature of 25° C. using an electronic pycnometer (manufactured by Alfa Mirage Co., Ltd., SD-200L).

[Table 4]

In Examples, it was confirmed that excellent heat dissipation was obtained. In Comparative Example 1, it was confirmed that sufficient heat dissipation was not obtained.

Symbol Description

10-semiconductor chip, 15-wiring, 20, 60-substrate, 30-connection bump, 32-bump, 34-through electrode, 40-sealing material, 42-adhesive for semiconductor, 50-interposer, 70 - solder mask, 90 - crimping tool, 100, 200, 300, 400, 500, 600 - semiconductor device, 700 - stacked chip.

Claims (11)

1. An adhesive for semiconductor, which is used for sealing a connection portion in a semiconductor device having a connection structure in which connection portions of a semiconductor chip and a printed circuit board are electrically connected to each other and/or a connection structure in which connection portions of a plurality of semiconductor chips are electrically connected to each other,

the adhesive for semiconductor comprises a curable resin component, a flux and an inorganic filler,

the content of the inorganic filler is 60 to 95 mass% based on the total amount of the adhesive for a semiconductor, and the thermal conductivity of the adhesive for a semiconductor after curing is 1.5W/mK or more.

2. The adhesive for semiconductors according to claim 1, wherein,

the inorganic filler contains polyhedral aluminum oxide.

3. The adhesive for semiconductors according to claim 1 or 2, wherein,

the inorganic filler contains at least one selected from the group consisting of silicon carbide, boron nitride, diamond, and aluminum nitride.

4. The adhesive for semiconductors according to any one of claims 1 to 3, wherein,

the inorganic filler has peaks in the respective ranges of 0.1 to 4.5 μm and 5 to 20 μm in the volume-based particle size distribution.

5. The adhesive for semiconductors according to any one of claims 1 to 4, wherein,

the inorganic filler is blended with a volume-based average particle diameter r ₁ Polyhedral alumina of 5 to 20 mu m and volume-based average particle diameter r ₂ Polyhedral alumina of 0.1-4.5 μm.

6. The adhesive for semiconductors according to claim 5, wherein,

the average particle diameter r ₁ With the average particle diameter r ₂ The difference (r) between ₁ -r ₂ ) Is 4-10 μm.

7. The adhesive for semiconductors according to any one of claims 1 to 6, which has a thermal conductivity of 3.0W/mK or more after curing.

8. The adhesive for semiconductors according to any one of claims 1 to 7, wherein,

the fluxing agent is a carboxylic acid.

9. The adhesive for semiconductors according to any one of claims 1 to 8, wherein,

the curable resin component contains a thermosetting resin, a curing agent, and a thermoplastic resin.

10. A method of manufacturing a semiconductor device having a connection structure in which respective connection portions of a semiconductor chip and a printed circuit board are electrically connected to each other and/or a connection structure in which respective connection portions of a plurality of semiconductor chips are electrically connected to each other, the method comprising:

a step of sealing at least a part of the connection part using the adhesive for semiconductors according to any one of claims 1 to 9.

11. A semiconductor device includes:

a connection structure in which respective connection portions of the semiconductor chip and the printed circuit board are electrically connected to each other and/or a connection structure in which respective connection portions of the plurality of semiconductor chips are electrically connected to each other; and

a sealing material sealing at least a part of the connection portion,

the sealing material contains a cured product of the adhesive for semiconductors according to any one of claims 1 to 9.

Images