Epoxy resin composition and electronic component device

Abstract

To provide an epoxy resin composition which suppresses occurrence of warpage and generation of voids when a cured product is formed on a semiconductor wafer.SOLUTION: An epoxy resin composition comprises an epoxy resin, a curing agent, a filler, and a solvent, wherein the epoxy resin comprises a reaction product of a phenol compound represented by a specific structure having an alkyl group or an allyl group, and a silicone-modified epoxy resin.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present disclosure relates to an epoxy resin composition and an electronic component device. [Background technology]

[0002] In recent years, in order to reduce the cost, size, thickness, weight, performance, and functionality of electronic component devices, progress has been made in increasing the density of packaging by miniaturizing the wiring of elements, increasing the number of layers and pins, and making packages smaller and thinner.As a result, electronic component devices that are approximately the same size as elements in an integrated circuit (IC), i.e., CSPs (chip size packages), have become widely used.

[0003] Among these, wafer-level chip-size packaging, which involves resin encapsulation at the semiconductor wafer stage, has attracted attention as the ultimate package. This wafer-level chip-size packaging involves encapsulating the surface of a semiconductor wafer, which has fine wiring for semiconductor elements and on whose surface rewiring and electrodes for external connection terminals are formed, with bumps formed on the electrodes or leads connected to them, with an epoxy resin composition. After soldering the bumps or leads, the semiconductor wafer is cut into individual elements to produce a finished product. This method encapsulates and singulates a large number of elements at the semiconductor wafer stage by transfer molding using a solid epoxy resin composition or printing molding using a liquid epoxy resin composition, thereby enabling significant streamlining of production compared to methods in which elements are encapsulated after singulation. However, in wafer-level chip size packages, the encapsulated semiconductor wafer is prone to warping, and this warping causes problems in each process after encapsulation, such as transportation, grinding, inspection, and singulation, resulting in variations in element characteristics depending on the device. To further reduce costs, wafer diameters tend to become larger and larger, and the larger the wafer diameter, the greater the warpage. Therefore, reducing the warpage of semiconductor wafers has become an important issue for the widespread use of wafer-level chip size packages.

[0004] Furthermore, liquid epoxy resin compositions used in the manufacture of wafer-level chip size packages by printing molding are required to have excellent bubble-breaking and defoaming properties when removing residual air in a decompression treatment step, and to have few residual voids in the cured product. In the field of element encapsulation for electronic devices such as transistors and ICs, resin encapsulation has traditionally been the mainstream due to its productivity and cost advantages, and epoxy resin molding materials have been widely used. This is because epoxy resins offer a good balance of various properties, including electrical properties, moisture resistance, heat resistance, mechanical properties, and adhesiveness to insert parts. The warpage of semiconductor wafers is influenced by stresses generated by the cure shrinkage of the epoxy resin composition, mismatches in the thermal expansion coefficients of the semiconductor wafer and the epoxy resin composition, etc., and may also reduce the reliability of the package. Therefore, epoxy resin compositions used for such applications must be made stress-reducing, and generally, it is considered effective to reduce the cure shrinkage of the epoxy resin composition, to decrease the thermal expansion coefficient by adding a high amount of inorganic filler, or to decrease the elastic modulus by using a flexibilizer, flexible resin, etc.

[0005] For example, Patent Document 1 discloses a liquid epoxy resin composition containing a naphthalene skeleton-type epoxy resin or a biphenyl skeleton-type epoxy resin to which silicone powder and silicone oil are added. Patent Documents 2 and 3 disclose liquid resin compositions containing a silicone-modified epoxy resin as the main component, and having a modulus of elasticity of the cured product at room temperature of 5 GPa or less. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 3397176 [Patent Document 2] Japanese Patent Application Laid-Open No. 2003-238651 [Patent Document 3] Japanese Patent Application Laid-Open No. 2003-238652 Summary of the Invention [Problem to be solved by the invention]

[0007] However, even with the liquid resin compositions disclosed in Patent Documents 1 to 3, there are still cases where the occurrence of warpage and voids in semiconductor wafers cannot be sufficiently suppressed. The present disclosure has been made in view of the above-mentioned conventional circumstances, and aims to provide an epoxy resin composition that suppresses the occurrence of warpage and voids when a cured product is formed on a semiconductor wafer, and an electronic component device using this epoxy resin composition. [Means for solving the problem]

[0008] Specific means for achieving the above object are as follows. <1> Contains an epoxy resin, a curing agent, a filler, and a solvent, The epoxy resin composition comprises a reaction product of a phenol compound represented by the following general formula (A) and a silicone-modified epoxy resin:

[0009] [ka]

[0010] (In the general formula (A), R 1 each independently represents an alkyl group or an aryl group, and each X independently represents an alkylene group or an arylene group. p represents 1 or 2, each m independently represents an integer of 0 to 4, and n represents an integer of 0 to 4 when p is 1, and represents an integer of 0 to 3 when p is 2. <2> The content of the solvent is 1% by mass to 10% by mass. <1> The epoxy resin composition according to claim 1. <3> The proportion of the filler in the solid content is 40% by mass to 95% by mass. <1> or <2> The epoxy resin composition according to claim 1. <4> The filler contains an inorganic filler, and the proportion of the inorganic filler in the filler is 50% by mass to 99.9% by mass. <1> ~ <3> 10. The epoxy resin composition according to claim 1, wherein the epoxy resin composition is <5> The curing agent includes an amine-based curing agent. <1> ~ <4> 10. The epoxy resin composition according to claim 1, wherein the epoxy resin composition is <6> Used for sealing wafer-level chip-size packages <1> ~ <5> 10. The epoxy resin composition according to claim 1, wherein the epoxy resin composition is <7> <1> ~ <6> 1. An electronic component device comprising an element encapsulated with the epoxy resin composition according to any one of claims 1 to 9. [Effects of the Invention]

[0011] According to the present disclosure, there are provided an epoxy resin composition that suppresses the occurrence of warpage and voids when a cured product is formed on a semiconductor wafer, and an electronic component device using this epoxy resin composition. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, embodiments for carrying out the present disclosure will be described in detail. However, the present disclosure is not limited to the following embodiments. In the following embodiments, components (including element steps, etc.) are not essential unless otherwise specified. The same applies to numerical values and their ranges, and do not limit the present disclosure.

[0013] In the present disclosure, the term "process" includes not only a process that is independent of other processes, but also a process that cannot be clearly distinguished from other processes as long as the purpose of the process is achieved. In the present disclosure, numerical ranges indicated using "to" include the numerical values before and after "to" as the minimum and maximum values, respectively. In the numerical ranges described in stages in this disclosure, the upper or lower limit value described in one numerical range may be replaced with the upper or lower limit value of another numerical range described in stages. Furthermore, in the numerical ranges described in this disclosure, the upper or lower limit value of that numerical range may be replaced with a value shown in the examples. In the present disclosure, each component may contain multiple substances corresponding to the component. When multiple substances corresponding to each component are present in the composition, the content or amount of each component means the total content or amount of the multiple substances present in the composition, unless otherwise specified. In the present disclosure, particles corresponding to each component may contain multiple types of particles. When multiple types of particles corresponding to each component are present in the composition, the particle size of each component means the value for a mixture of the multiple types of particles present in the composition, unless otherwise specified. In the present disclosure, the terms "layer" and "film" include cases where the layer or film is formed over the entire area when the area in which the layer or film is present is observed, as well as cases where the layer or film is formed over only a portion of the area. In the present disclosure, the "solid content" of an epoxy resin composition refers to the components excluding the solvent from the entire composition of the epoxy resin composition.

[0014] <Epoxy resin composition> The epoxy resin composition of the present disclosure comprises an epoxy resin, a curing agent, a filler, and a solvent, and the epoxy resin comprises a reaction product of a phenolic compound represented by the following general formula (A) with a silicone-modified epoxy resin (hereinafter, sometimes referred to as a specific epoxy resin):

[0015] [ka]

[0016] In general formula (A), R 1each independently represents an alkyl group or an aryl group, and each X independently represents an alkylene group or an arylene group. p represents 1 or 2, each m independently represents an integer of 0 to 4, and n represents an integer of 0 to 4 when p is 1, or an integer of 0 to 3 when p is 2.

[0017] As a result of extensive research, the present inventors have found that use of the epoxy resin composition of the present disclosure containing a specific epoxy resin can suppress the occurrence of warpage and voids when a cured product is formed on a semiconductor wafer, and have completed the present invention.

[0018] The epoxy resin composition of the present disclosure contains an epoxy resin, a curing agent, a filler, and a solvent, and may contain other components as needed. Hereinafter, each component constituting the epoxy resin composition of the present disclosure will be described.

[0019] -Epoxy resin- The epoxy resin composition contains a specific epoxy resin. The epoxy resin composition may contain an epoxy resin other than the specific epoxy resin.

[0020] (Specific epoxy resin) The specific epoxy resin includes a reaction product of a phenol compound represented by general formula (A) and a silicone-modified epoxy resin.

[0021] In general formula (A), R 1 is an alkyl group or an aryl group, and multiple R 1 may be the same or different. In general formula (A), R 1 The alkyl group represented by R is preferably an alkyl group having 1 to 5 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms, and even more preferably an alkyl group having 1 or 2 carbon atoms. 1Specific examples of the alkyl group represented by the formula (I) include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, an s-butyl group, a t-butyl group, an n-pentyl group, a neopentyl group, an isopentyl group, an s-pentyl group, a 3-pentyl group, and a t-pentyl group.

[0022] In general formula (A), the alkylene group represented by X may be linear or branched, and is preferably an alkylene group having 1 to 20 carbon atoms, more preferably an alkylene group having 1 to 15 carbon atoms, and even more preferably an alkylene group having 1 to 10 carbon atoms. Specific examples of the alkylene group represented by X include a methylene group, an ethylene group, a tetramethylene group, a hexamethylene group, a heptamethylene group, an octamethylene group, a nonamethylene group, a decamethylene group, an undecamethylene group, a dodecamethylene group, a 2-methylpentamethylene group, a 2-methylhexamethylene group, a 2-methylheptamethylene group, a 2-methyloctamethylene group, a 2-methylnonamethylene group, a 2-methyldecamethylene group, and an isopropylidene group (>C(CH3)2).

[0023] In general formula (A), the arylene group represented by X is preferably an arylene group having 6 to 25 carbon atoms, and more preferably an arylene group having 6 to 14 carbon atoms. Specific examples of the arylene group represented by X include a phenylene group, a biphenylylene group (-C6H4-C6H4-), and a naphthylene group.

[0024] In formula (A), each m independently represents an integer of 0 to 4, with 0 or 1 being preferred. In the general formula (A), p represents 1 or 2. In formula (A), when p is 1, n represents an integer of 0 to 4, preferably 0 or 1. When p is 2, n represents an integer of 0 to 3, preferably 0 or 1.

[0025] In general formula (A), R 1When at least one of the groups is an allyl group, the allyl group is preferably substituted at the ortho position relative to the phenolic hydroxyl group.

[0026] The phenol compound represented by general formula (A) is R 1 is an allyl group, p is 1, X is an alkylene group, and m and n are both 0 or 1, and 1 is an allyl group, p is 1, X is a methylene group or an isopropylidene group, and m and n are both 0 or 1, and more preferred are compounds in which R 1 is an allyl group, p is 1, X is an isopropylidene group, and m and n are both 1, or p is 1, X is a methylene group, and m and n are both 0.

[0027] The hydroxyl group equivalent of the phenol compound represented by general formula (A) is preferably 50 g / eq to 500 g / eq, more preferably 70 g / eq to 400 g / eq, and even more preferably 90 g / eq to 300 g / eq. In the present disclosure, the hydroxyl equivalent weight refers to a value calculated from the hydroxyl value determined in accordance with JIS K7236:2009.

[0028] Commercially available industrially available phenol compounds represented by general formula (A) include 2,2'-diallylbisphenol A (DABPA, hydroxyl equivalent: 154 g / eq, Daiwa Chemical Industry Co., Ltd.), Resitop SBA (hydroxyl equivalent: 260 g / eq), Resitop APG (hydroxyl equivalent: 148 g / eq), Resitop LVA (hydroxyl equivalent: 154 g / eq), and Resitop BPF-SG (high-purity bisphenol F, hydroxyl equivalent: 100 g / eq) (all manufactured by Gun-ei Chemical Industry Co., Ltd.).

[0029] The phenol compound represented by the general formula (A) may be used alone or in combination of two or more kinds.

[0030] The silicone-modified epoxy resin is not particularly limited as long as it has a siloxane structure in the molecule. Among them, the silicone-modified epoxy resin is preferably a compound represented by the following general formula (B).

[0031] [ka]

[0032] In general formula (B), R 2 is an alkyl group or a phenyl group, and a plurality of R 2 may be the same or different. In general formula (B), R 2 Specific examples of include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, and a phenyl group, and a methyl group is preferred. In general formula (B), q is an integer of 1 or more, preferably 25 or less, and more preferably 15 or less. Examples of commercially available compounds of general formula (B) include KF-105, X22-163A (Shin-Etsu Chemical Co., Ltd.), and TSL9906 (Momentive Performance Materials Japan, LLC).

[0033] The compound represented by general formula (B) may be used alone or in combination of two or more.

[0034] The epoxy equivalent of the compound represented by general formula (B) is preferably 1000 g / eq or less, more preferably 600 g / eq or less, and may be 150 g / eq or more. In the present disclosure, the epoxy equivalent weight refers to a value measured by perchloric acid titration in accordance with JIS K7236:2009.

[0035] The reaction product of the phenolic compound represented by general formula (A) and the silicone-modified epoxy resin can be obtained, for example, by mixing the phenolic compound represented by general formula (A) with the compound represented by general formula (B), adding a catalyst if necessary, and further adding an organic solvent if necessary, and then heating the mixture to react. Examples of the catalyst include the following: Specifically, cycloamidine compounds such as 1,8-diazabicyclo[5.4.0]undecene-7 (DBU), 1,5-diazabicyclo[4.3.0]nonene, and 5,6-dibutylamino-1,8-diazabicyclo[5.4.0]undecene-7, cycloamidine compounds containing maleic anhydride, 1,4-benzoquinone, 2,5-toluquinone, 1,4-naphthoquinone, 2,3-dimethylbenzoquinone, 2,6-dimethylbenzoquinone, and 2,3-dimethoxy-5-methyl- Quinone compounds such as 1,4-benzoquinone, 2,3-dimethoxy-1,4-benzoquinone, and phenyl-1,4-benzoquinone; compounds with intramolecular polarization formed by adding compounds with π bonds such as diazophenylmethane and phenolic resins; tertiary amine compounds such as benzyldimethylamine, triethanolamine, dimethylaminoethanol, and tris(dimethylaminomethyl)phenol; derivatives of tertiary amine compounds; 2-methylimidazole, 2-phenylimidazole, and imidazole compounds such as 2-phenyl-4-methylimidazole; derivatives of imidazole compounds; organic phosphine compounds such as tributylphosphine, methyldiphenylphosphine, triphenylphosphine, tris(4-methylphenyl)phosphine, diphenylphosphine, and phenylphosphine; phosphorus compounds having intramolecular polarization obtained by adding a compound having a π bond such as maleic anhydride, the above-mentioned quinone compounds, diazophenylmethane, or a phenol resin to an organic phosphine compound; tetraphenylborate salts such as tetraphenylphosphonium tetraphenylborate, triphenylphosphonium tetraphenylborate, 2-ethyl-4-methylimidazolium tetraphenylborate, and N-methylmorpholinium tetraphenylborate; derivatives of tetraphenylborate salts; and triphenylborane complexes such as triphenylphosphine-triphenylborane complex and morpholine-triphenylborane complex. The equivalent ratio of the phenol compound represented by general formula (A) to the silicone-modified epoxy resin during the reaction is preferably 1-5 in terms of epoxy equivalent / hydroxyl group equivalent.

[0036] The epoxy equivalent of the specific epoxy resin is preferably 400 g / eq to 2000 g / eq, and more preferably 600 g / eq to 1500 g / eq.

[0037] (Other epoxy resins) The epoxy resin composition may contain an epoxy resin other than the specific epoxy resin. Other epoxy resins include monofunctional aliphatic epoxy compounds having one epoxy group in the molecule, such as alkyl alcohol glycidyl ethers (butyl glycidyl ether, 2-ethylhexyl glycidyl ether, etc.) and alkenyl alcohol glycidyl ethers (vinyl glycidyl ether, allyl glycidyl ether, etc.); bifunctional aliphatic epoxy compounds having two epoxy groups in the molecule, such as alkylene glycol diglycidyl ether and alkenylene glycol diglycidyl ether; and polyglycidyl ethers of trifunctional or higher alcohols, such as trimethylolpropane, pentaerythritol, and dipentaerythritol (tri- or tetra-glycidyl ether, dipentaerythritol (tri-, tetra-, penta-, or hexa-glycidyl ether, etc.) having an epoxy group in the molecule. Examples of epoxy compounds include polyfunctional aliphatic epoxy compounds having three or more alkyl groups, glycidyl ethers of bifunctional phenols such as bisphenol A, bisphenol F, bisphenol AD, bisphenol S, catechol, and resorcinol, hydrogenated bisphenol A diglycidyl ether, hydrogenated bisphenol F diglycidyl ether, glycidyl ether esters of hydroxycarboxylic acids such as p-hydroxybenzoic acid, monoglycidyl esters or polyglycidyl esters of carboxylic acids such as benzoic acid, phthalic acid, and terephthalic acid, glycidylamine-type epoxy compounds such as diglycidyl aniline, diglycidyl toluidine, triglycidyl-p-aminophenol, and tetraglycidyl-m-xylylenediamine, and epoxy compounds having a naphthalene skeleton such as glycidyl esters of naphthol and glycidyl ether esters of β-hydroxynaphthoic acid. Among these, from the viewpoint of obtaining a cured product with a high glass transition temperature, preferred are glycidyl ethers of bifunctional phenols, hydrogenated bisphenol A diglycidyl ether, etc. Furthermore, from the viewpoint of obtaining an epoxy resin composition with a low viscosity, preferred are glycidyl ethers of bifunctional phenols, bifunctional aliphatic epoxy compounds, or polyfunctional aliphatic epoxy compounds.

[0038] The proportion of the specific epoxy resin in the epoxy resin is preferably 10% by mass or more, more preferably 10% by mass to 70% by mass, even more preferably 10% by mass to 65% by mass, and particularly preferably 15% by mass to 60% by mass.

[0039] From the viewpoint of preventing corrosion of aluminum wiring or copper wiring on elements such as ICs, the epoxy resin preferably has a high purity and a low hydrolyzable chlorine content. From the viewpoint of improving the moisture resistance of the epoxy resin composition, the hydrolyzable chlorine content is preferably 500 ppm by mass or less.

[0040] Here, the amount of hydrolyzable chlorine is a value determined by dissolving 1 g of a sample epoxy resin in 30 mL of dioxane, adding 5 mL of 1N-KOH methanol solution, refluxing for 30 minutes, and then performing potentiometric titration.

[0041] The content of the epoxy resin in the solid content of the epoxy resin composition is preferably 1.5 to 20 mass%, more preferably 2.0 to 15 mass%, and even more preferably 3.0 to 10 mass%. The content of the epoxy resin in the solid content of the epoxy resin composition excluding the filler is preferably 30% by mass to 85% by mass, more preferably 35% by mass to 80% by mass, and even more preferably 40% by mass to 80% by mass.

[0042] - Hardener - The epoxy resin composition contains a curing agent. The curing agent may be either liquid or solid at 25°C, as long as it undergoes a polymerization reaction with the epoxy resin. Examples of the curing agent include amine-based curing agents, phenol-based curing agents, acid anhydride-based curing agents, etc. Among these, amine-based curing agents are preferred as the curing agent.

[0043] Examples of the amine-based curing agent include chain aliphatic amines, cyclic aliphatic amines, aliphatic aromatic amines, and aromatic amines. From the viewpoint of heat resistance and electrical properties, aromatic amines are preferred, and aromatic amines in which an amino group is directly bonded to an aromatic ring and one or two aromatic rings are contained in one molecule are more preferred. Specific examples of the amine curing agent include aromatic amine curing agents having one aromatic ring, such as m-phenylenediamine, 1,3-diaminotoluene, 1,4-diaminotoluene, 2,4-diaminotoluene, 3,5-diethyl-2,4-diaminotoluene, 3,5-diethyl-2,6-diaminotoluene, and other diethyltoluenediamines, and 2,4-diaminoanisole; 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylsulfone, 4,4'-methylenebis(2-ethylaniline), 3,3'-diethyl-4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylsulfone, 4,4'-methylenebis(2-ethylaniline), and 3,3'-diethyl-4,4'-diaminodiphenylmethane; aromatic amine curing agents having two aromatic rings, such as 3,3',5,5'-tetramethyl-4,4'-diaminodiphenylmethane, 3,3',5,5'-tetramethyl-4,4'-diaminodiphenylmethane, and 3,3',5,5'-tetraethyl-4,4'-diaminodiphenylmethane; hydrolysis condensates of aromatic amine curing agents; aromatic amine curing agents having a polyether structure, such as polytetramethylene oxide di-p-aminobenzoate and polytetramethylene oxide di-para-aminobenzoate; condensates of aromatic diamines and epichlorohydrin; and reaction products of aromatic diamines and styrene.

[0044] Commercially available amine curing agents may be used. Specific examples of commercially available amine curing agents include amine curing agent manufactured by Nippon Kayaku Co., Ltd. (product name: Kayahard-AA) and amine curing agents manufactured by Mitsubishi Chemical Corporation (product names: jER Cure (registered trademark) 113, jER Cure (registered trademark) W, etc.), but the amine curing agents are not limited to these specific examples. A single type of amine curing agent may be used alone, or two or more types may be used in combination.

[0045] Acid anhydride curing agents include phthalic anhydride, maleic anhydride, methyl himic anhydride, himic anhydride, succinic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, chlorendic anhydride, methyltetrahydrophthalic anhydride, 3-methylhexahydrophthalic anhydride, 4-methylhexahydrophthalic anhydride, trialkyltetrahydrophthalic anhydride maleic acid adduct, benzophenonetetracarboxylic anhydride, trimellitic anhydride, pyromellitic anhydride, hydrogenated methylnadic anhydride, and various cyclic acid anhydrides such as trialkyltetrahydrophthalic anhydrides having multiple alkyl groups obtained by Diels-Alder reaction from maleic anhydride and diene compounds, and dodecenyl succinic anhydride.

[0046] Examples of phenolic curing agents include novolak resins obtained by condensing or co-condensing at least one selected from the group consisting of phenolic compounds (e.g., phenol, cresol, xylenol, resorcinol, catechol, bisphenol A, and bisphenol F) and naphthol compounds (e.g., α-naphthol, β-naphthol, and dihydroxynaphthalene) with an aldehyde compound (e.g., formaldehyde, acetaldehyde, propionaldehyde, benzaldehyde, and salicylaldehyde) under an acidic catalyst; phenol-aralkyl resins; biphenyl-aralkyl resins; and naphthol-aralkyl resins. The curing agent may be used alone or in combination of two or more kinds.

[0047] The ratio of the equivalent number of the functional group of the curing agent (for example, the active hydrogen of the amino group in the case of an amine-based curing agent, a phenolic hydroxyl group in the case of a phenol-based curing agent, or an acid anhydride group in the case of an acid anhydride-based curing agent) to the equivalent number of the epoxy group of the epoxy resin (equivalent number of curing agent / equivalent number of epoxy resin) can be set in the range of 0.6 to 1.4, or alternatively, in the range of 0.7 to 1.3, or alternatively, in the range of 0.8 to 1.2.

[0048] -Filler- The epoxy resin composition contains a filler. The filler may be an inorganic filler or an organic filler. The proportion of the filler in the solid content of the epoxy resin composition is preferably 40% by mass to 95% by mass, more preferably 50% by mass to 95% by mass, and even more preferably 60% by mass to 95% by mass.

[0049] Examples of inorganic fillers include silica such as spherical silica and crystalline silica, calcium carbonate, clay, alumina, silicon nitride, silicon carbide, boron nitride, calcium silicate, potassium titanate, aluminum nitride, beryllia, zirconia, zircon, fosterite, steatite, spinel, mullite, and titania powders, as well as beads of these spheroidized fillers and glass fibers. Furthermore, examples of inorganic fillers with flame retardant properties include aluminum hydroxide, magnesium hydroxide, zinc borate, and zinc molybdate. These inorganic fillers may be used alone or in combination. Among these, spherical silica is preferred from the viewpoint of reducing the linear expansion coefficient, and alumina is preferred from the viewpoint of high thermal conductivity. The shape of the inorganic filler is preferably spherical from the viewpoint of high loading of the inorganic filler and fluidity and penetration of the epoxy resin composition into fine gaps. The inorganic filler may be an untreated filler or may be one that has been treated in advance with a coupling agent described below.

[0050] The particle size of the inorganic filler is preferably 1 μm to 20 μm, more preferably 1.5 μm to 15 μm, and even more preferably 2 μm to 10 μm. If the average particle size of the inorganic filler is 1 μm or more, it tends to be easier to disperse the inorganic filler at a high concentration in the epoxy resin composition. If the average particle size of the inorganic filler is 20 μm or less, the amount of coarse particle components in the inorganic filler is reduced, which tends to prevent insufficient filling of the epoxy resin composition into fine gaps or streaky defects during printing, and to improve surface smoothness. In the present disclosure, the average particle size refers to the particle size at which the volume cumulative particle size distribution measured using a laser diffraction method is 50%.

[0051] When the filler contains an inorganic filler, the proportion of the inorganic filler in the filler is preferably 50% by mass to 99.9% by mass, more preferably 80% by mass to 99.5% by mass, and even more preferably 90% by mass to 99.5% by mass, from the viewpoint of mechanical strength.

[0052] In the present disclosure, an organic filler refers to an organic compound having a particulate or fibrous shape. Examples of organic compounds constituting the organic filler include resin components such as urea-formaldehyde resin, polycarbonate resin, melamine resin, unsaturated polyester resin, polyurethane resin, polyolefin resin, acrylic resin, fluororesin, polystyrene resin, cellulose, formaldehyde resin, coumarone-indene resin, lignin, petroleum resin, amino resin, polyester resin, polyethersulfone resin, butadiene resin, and copolymers thereof. These resin components may be used alone or in combination of two or more. Furthermore, rubber particles may be used as the organic filler. Examples of rubber particles include styrene-butadiene rubber (SBR), nitrile-butadiene rubber (NBR), butadiene rubber (BR), urethane rubber (UR), and acrylic rubber (AR). Among these, rubber particles made of acrylic rubber are preferred from the viewpoint of heat resistance and moisture resistance, and core-shell type acrylic polymers, i.e., core-shell type acrylic rubber particles, are more preferred. Silicone rubber particles can also be used as rubber particles other than those mentioned above. Examples of silicone rubber particles include silicone rubber particles crosslinked with polyorganosiloxanes such as linear polydimethylsiloxane, polymethylphenylsiloxane, and polydiphenylsiloxane; silicone rubber particles whose surfaces are coated with silicone resin; and core-shell polymer particles consisting of a core of solid silicone particles obtained by emulsion polymerization or the like and a shell of an organic polymer such as acrylic resin. These silicone polymer particles can be either amorphous or spherical in shape, but spherical particles are preferred in order to maintain a low viscosity, which affects the moldability of the epoxy resin composition. These silicone polymer particles are commercially available from Dow Corning Toray Silicone Co., Ltd., Shin-Etsu Chemical Co., Ltd., and other companies.

[0053] The organic filler is preferably spherical, and the average particle size is preferably 0.05 μm to 4 μm, more preferably 0.08 μm to 3 μm.

[0054] When the filler contains an organic filler, the proportion of the organic filler in the filler is preferably 0.1% by mass to 50% by mass, more preferably 0.5% by mass to 20% by mass, and even more preferably 0.5% by mass to 10% by mass, from the viewpoint of flexibility.

[0055] When the filler contains silicone rubber particles, the proportion of the silicone rubber particles in the filler is preferably 0.1% by mass to 50% by mass, more preferably 0.5% by mass to 20% by mass, and even more preferably 0.5% by mass to 10% by mass, from the viewpoint of reducing warpage. If the proportion of silicone rubber particles is 0.1% by mass or more, sufficient stress reduction can be achieved, and the warpage suppression effect tends to be greater, while if it is 50% by mass or less, the strength and moisture resistance of the cured product tend not to decrease. When an organic filler is used as the filler, only silicone rubber particles may be used, or only an organic filler composed of a resin component may be used, or both may be used in combination.

[0056] -solvent- The epoxy resin composition contains a solvent. The solvent is a component that imparts optimal viscosity and thixotropy index to the epoxy resin composition for printability. To avoid void formation due to solvent evaporation during heat curing of the epoxy resin composition and to suppress viscosity changes of the epoxy resin composition due to solvent evaporation during printing, a solvent with a boiling point of 170°C or higher is preferred, and a solvent with a boiling point of 200°C or higher is more preferred. Furthermore, when forming a coating film by vacuum printing, the epoxy resin composition is constantly handled under vacuum, which may cause the solvent to gradually evaporate and result in viscosity changes. In this case, a solvent with a boiling point in the range of 240°C to 300°C is preferred.

[0057] Specific examples of the solvent include diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monobutyl ether, triethylene glycol monobutyl ether, tetraethylene glycol monobutyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, ethylene glycol monohexyl ether, diethylene glycol monohexyl ether, ethylene glycol monophenyl ether, ethylene glycol mono-2-ethylhexyl ether, diethylene glycol mono-2-ethylhexyl ether, propylene glycol monobutyl ether, and dipropylene glycol. monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monobutyl ether, dipropylene glycol monopropyl ether, tripropylene glycol monomethyl ether, propylene glycol mono-n-butyl ether, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, 3-methyl-3-methoxybutyl acetate, butyl carbitol acetate, 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, 2,2,4-trimethyl-1,3-pentanediol diisobutyrate, γ-butyrolactone, and the like. These may be used alone or in combination of two or more.

[0058] The content of the solvent in the epoxy resin composition is preferably 1% by mass to 10% by mass, more preferably 2% by mass to 8% by mass, and even more preferably 3% by mass to 6% by mass. If the content of the solvent is 1% by mass or more, the viscosity of the epoxy resin composition does not become too high, and the coating workability and printability tend not to deteriorate. If the content of the solvent is 10% by mass or less, the viscosity of the epoxy resin composition does not decrease too much, and the phenomenon of the epoxy resin composition flowing to the backside of the wafer after printing and the occurrence of voids during curing tend not to occur.

[0059] -Other ingredients- The epoxy resin composition may contain other components other than the epoxy resin, curing agent, filler, and solvent, if necessary.

[0060] (Curing accelerator) The epoxy resin composition may further contain a curing accelerator. The type of the curing accelerator is not particularly limited, and known curing accelerators can be used. Specific examples of known curing accelerators include the compounds exemplified as specific examples of the above-mentioned catalysts used when synthesizing the reaction product of the phenol compound represented by the general formula (A) and the silicone-modified epoxy resin. The curing accelerator may be used alone or in combination of two or more kinds.

[0061] (Ion trap agent) The epoxy resin composition may further contain an ion trap agent. The ion trap agent that can be used in the present disclosure is not particularly limited as long as it is a commonly used ion trap agent in the encapsulant used for the production of semiconductor devices. Examples of the ion trap agent include compounds represented by the following general formula (VI-1) or the following general formula (VI-2).

[0062] Mg 1-a Al a (OH)2(CO3) a / 2 ·uH2O (VI-1) (In the general formula (VI-1), a is 0 < a ≤ 0.5, and u is a positive number.) BiO b (OH) c (NO3) d (VI-2) (In the general formula (VI-2), b is 0.9 ≤ b ≤ 1.1, c is 0.6 ≤ c ≤ 0.8, and d is 0.2 ≤ d ≤ 0.4.)

[0063] Ion trapping agents are commercially available. For example, "DHT-4A" (Kyowa Chemical Industry Co., Ltd., trade name) is a commercially available compound represented by general formula (VI-1). For example, "IXE500" (Toagosei Co., Ltd., trade name) is a commercially available compound represented by general formula (VI-2).

[0064] Other examples of ion trapping agents include hydrous oxides of elements selected from magnesium, aluminum, titanium, zirconium, antimony, and the like. The ion trapping agent may be used alone or in combination of two or more types.

[0065] When the epoxy resin composition contains an ion trapping agent, the content of the ion trapping agent is preferably 1 part by mass or more per 100 parts by mass of the epoxy resin from the viewpoint of realizing sufficient moisture resistance reliability, and is preferably 15 parts by mass or less per 100 parts by mass of the epoxy resin from the viewpoint of fully exhibiting the effects of the other components.

[0066] The average particle size of the ion trapping agent is preferably 0.1 μm to 3.0 μm, and the maximum particle size is preferably 10 μm or less.

[0067] (coupling agent) The epoxy resin composition may further contain a coupling agent. The type of coupling agent is not particularly limited, and known coupling agents can be used. Examples of the coupling agent include silane coupling agents and titanium coupling agents. One type of coupling agent may be used alone, or two or more types may be used in combination.

[0068] Examples of silane coupling agents include vinyltrichlorosilane, vinyltriethoxysilane, vinyltris(β-methoxyethoxy)silane, γ-methacryloxypropyltrimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane (3-glycidoxypropyltrimethoxysilane), vinyltriacetoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-[bis(β-hydroxyethyl)]aminopropyltriethoxysilane, N-(β-aminoethyl)- Examples include γ-aminopropyltrimethoxysilane, γ-(β-aminoethylamino)propyldimethoxymethylsilane, N-(dimethoxymethylsilylisopropyl)ethylenediamine, methyltrimethoxysilane, methyltriethoxysilane, N-(β-(N-vinylbenzylamino)ethyl)-γ-aminopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, hexamethyldisilane, γ-anilinopropyltrimethoxysilane, vinyltrimethoxysilane, decyltrimethoxysilane, hexyltrimethoxysilane, and γ-mercaptopropylmethyldimethoxysilane.

[0069] Examples of titanium coupling agents include isopropyl triisostearoyl titanate, isopropyl tris(dioctyl pyrophosphate) titanate, isopropyl tri(N-aminoethyl-aminoethyl) titanate, tetraoctyl bis(ditridecyl phosphite) titanate, tetra(2,2-diallyloxymethyl-1-butyl)bis(ditridecyl phosphite) titanate, bis(dioctyl pyrophosphate)oxyacetate titanate, bis(dioctyl pyrophosphate)ethylene titanate, isopropyl trioctanoyl titanate, isopropyl dimethacryl isostearoyl titanate, isopropyl tridodecyl benzenesulfonyl titanate, isopropyl isostearoyl diacryl titanate, isopropyl tri(dioctyl phosphate) titanate, isopropyl tricumyl phenyl titanate, and tetraisopropyl bis(dioctyl phosphite) titanate.

[0070] When the epoxy resin composition contains a coupling agent, the content of the coupling agent is preferably 10% by mass or less based on the total solid content of the epoxy resin composition, and from the viewpoint of fully exerting its effects, it is preferably 0.1% by mass or more.

[0071] (mold release agent) The epoxy resin composition may further contain a release agent. The type of release agent is not particularly limited, and known release agents can be used. Specific examples include higher fatty acids, carnauba wax, and polyethylene wax. One type of release agent may be used alone, or two or more types may be used in combination. When the epoxy resin composition contains a release agent, the content of the release agent is preferably 10% by mass or less, based on the total amount of the epoxy resin and the curing agent, and from the viewpoint of exerting its effect, it is preferably 0.5% by mass or more.

[0072] (coloring agent) The epoxy resin composition may contain a colorant (for example, carbon black). The colorant may be used alone or in combination of two or more.

[0073] When conductive particles such as carbon black are used as the colorant, the content of conductive particles having a particle diameter of 10 μm or more is preferably 1 mass % or less. When the epoxy resin composition contains conductive particles, the content of the conductive particles is preferably 3 mass % or less based on the total amount of the epoxy resin and the curing agent.

[0074] The epoxy resin composition may contain, as other components, silicone oil; surfactants; antioxidants; nitrogen-containing compounds such as phosphoric acid esters, melamine, melamine derivatives, compounds having a triazine ring, cyanuric acid derivatives, isocyanuric acid derivatives; phosphorus-nitrogen-containing compounds such as cyclophosphazene; metal compounds such as zinc oxide, iron oxide, molybdenum oxide, and ferrocene; antimony oxides such as antimony trioxide, antimony tetraoxide, and antimony pentoxide; and conventionally known flame retardants such as brominated epoxy resins; dispersants, and the like, as needed.

[0075] The epoxy resin composition may be prepared by any method that can uniformly disperse and mix the various components described above. Typical methods for preparing an epoxy resin composition include weighing predetermined amounts of components and dispersing and kneading them using a three-roll mill, a mortar and pestle mixer, a planetary mixer, a hard mixer, a homomixer, or the like. Furthermore, a method using a masterbatch in which the components are pre-dispersed and pre-heated is preferred from the viewpoints of uniform dispersion and flowability.

[0076] The curing conditions for the epoxy resin composition are not particularly limited. The heat treatment temperature is preferably 120°C to 250°C, more preferably 130°C to 220°C, and even more preferably 130°C to 210°C. The heat treatment time is preferably 15 minutes to 4 hours, and more preferably 30 minutes to 4 hours. The heat treatment temperature may be increased stepwise.

[0077] The glass transition temperature (Tg) of the cured product of the epoxy resin composition measured by DMA is preferably 80°C or higher, more preferably 90°C or higher.

[0078] The viscosity of the epoxy resin composition at 25°C is preferably less than 1000 Pa·s, more preferably 800 Pa·s or less, and even more preferably 500 Pa·s or less. The viscosity of the epoxy resin composition at 25°C is a value measured using a rotational shear viscometer at a rotation speed of 5 rpm. The epoxy resin composition preferably has a thixotropic index [(viscosity at 1 rpm) / (viscosity at 5 rpm)], which is the ratio of the viscosity at a rotational speed of 1 rpm to the viscosity at a rotational speed of 5 rpm measured at 25°C using a rotational shear viscometer, of 0.3 to 1.5, more preferably 0.5 to 1.2. When the thixotropic index is within the above range, the filling property tends to be further improved. The viscosity and thixotropy index of the epoxy resin composition can be adjusted to fall within a desired range by appropriately selecting the composition of the epoxy resin, the content of the filler, and the like.

[0079] The epoxy resin composition of the present disclosure is suitable for use in encapsulating wafer-level chip-size packages, which will be described later. The epoxy resin composition of the present disclosure tends to suppress the occurrence of repellency when the epoxy resin composition is applied to the surface of a semiconductor wafer by a printing method or the like.

[0080] <Electronic component equipment> The electronic component device of the present disclosure includes an element encapsulated with the epoxy resin composition of the present disclosure. Examples of electronic component devices include electronic component devices obtained by mounting electronic components such as active elements such as semiconductor chips, transistors, diodes, and thyristors, and passive elements such as capacitors, resistors, resistor arrays, coils, and switches on a support member such as a lead frame, a pre-wired tape carrier, a wiring board, glass, or a silicon wafer, and then sealing necessary parts with the epoxy resin composition of the present disclosure. In particular, the epoxy resin composition of the present disclosure is effective for electronic component devices that require low warpage and high reliability, and is particularly suitable for encapsulating wafer-level chip-size packages. Semiconductor wafers encapsulated with the epoxy resin composition of the present disclosure are less likely to experience warpage problems during processes such as transportation, grinding, inspection, and singulation after encapsulation. Furthermore, when the Tg of the cured product of the epoxy resin composition is 90°C or higher, chipping tends to be less likely to occur during processing such as dicing. Methods for encapsulating elements using the epoxy resin composition of the present disclosure include dispensing, casting, and printing, with the printing method being particularly preferred. [Example]

[0081] The present disclosure will be described in more detail below based on examples, but the present disclosure is not limited to the following examples. In the following examples, parts and % represent parts by mass and % by mass unless otherwise specified.

[0082] [Examples 1 to 5 and Comparative Example 1] The materials shown in Table 1 were kneaded and dispersed using a triple roll mill and a mortar and pestle mill, and then vacuum degassed to prepare the epoxy resin compositions described in the Examples and Comparative Examples. The units of the composition of each component listed in Table 1 are parts by mass, excluding the solvent. In Table 1, "Inorganic filler (mass%)" means the mass proportion of the inorganic filler in the solid content, and "Inorganic filler (mass parts)" indicates the mass amount of the inorganic filler used in preparing the epoxy resin composition. In Table 1, "solvent (mass %)" means the mass ratio of the solvent to the epoxy resin composition.

[0083] The prepared epoxy resin compositions were evaluated by the following tests, and the results are summarized in Table 1.

[0084] (Initial viscosity and thixotropy index) The viscosity of the epoxy resin composition produced by the above method was measured at 25°C and 5 rpm. The viscosity of the epoxy resin composition measured at 25°C and 1 rpm was divided by the viscosity measured at 25°C and 5 rpm to obtain a thixotropic index.

[0085] (Pot life (PL)) The epoxy resin compositions produced by the above method were allowed to stand at 25°C for 24 hours, and then their viscosity was measured at 25°C and 5 revolutions per minute using a rotational shear viscometer. The rate of increase from the initial viscosity was determined as the pot life. PL = (viscosity after 24 hours standing - initial viscosity) / initial viscosity x 100

[0086] (warp) An epoxy resin composition layer 198 mm in diameter and 300 μm in thickness was formed on a silicon wafer 200 mm in diameter and 500 μm in thickness using a mold, and the wafer was heat-cured at 130°C for 60 minutes and then at 200°C for 120 minutes to prepare a sample. After curing, the height difference between the center of the silicon wafer and the edge of the epoxy resin composition coating was measured as warpage using a Keyence Corporation three-dimensional measuring machine.

[0087] (Color unevenness) A silicon wafer with a diameter of 200 mm and a thickness of 500 μm was half-cut diced, and a mold was used to form an epoxy resin composition layer with a diameter of 198 mm and a thickness of 300 μm, which was then heat-cured at 130°C for 60 minutes and then at 200°C for 120 minutes to prepare a sample. After curing, the wafer was cut using a diamond pen, and the cross section was observed to evaluate color unevenness according to the following criteria. A: Has a uniform color B: Whitish mottled color

[0088] (Void) A silicon wafer with a diameter of 200 mm and a thickness of 500 μm was subjected to half-cut dicing, and a mold was used to form an epoxy resin composition layer with a diameter of 198 mm and a thickness of 300 μm. The layer was then heated and cured at 130°C for 60 minutes and then at 200°C for 120 minutes to prepare a sample. After curing, the wafer was cut using a diamond pen, and the presence or absence of voids in the cross section was evaluated according to the following criteria. A: No voids exist B: Voids with a diameter of less than 60 μm are present C: Voids with a diameter of 60 μm or more exist

[0089] [Table 1]

[0090] The details of each material in Table 1 are as follows: In Table 1, "-" means that the corresponding material was not used.

[0091] (Synthesis of epoxy resin 1) 453 g of DABPA, 1152 g of KF-105, and 427 g of TSL9906 were weighed and added to a 3-liter flask equipped with a nitrogen inlet tube, thermometer, condenser, dropping funnel, and mechanical stirrer, and the mixture was stirred until the liquid temperature reached 140°C. Next, 20 g of DBU, 295 g of KF-105, and 109 g of TSL9906 were weighed and premixed until homogeneous. The mixture was then added dropwise to the flask using the dropping funnel. After the addition was complete, the mixture was allowed to react at 150°C for 5 hours to obtain Epoxy Resin 1. The viscosity, number average molecular weight (Mn), and weight average molecular weight (Mw) of Epoxy Resin 1 at 25°C are shown in Table 2. The viscosity at 25°C was measured using a rotational shear viscometer at 20 revolutions per minute. The molecular weights (Mn and Mw) of the epoxy resin were measured by GPC using tetrahydrofuran (THF) as an eluent and calculated in terms of standard polystyrene.

[0092] (Synthesis of epoxy resin 2) Epoxy Resin 2 was obtained by the same reaction as in the synthesis of Epoxy Resin 1, except that the amounts of each material were changed as follows. 317 g of BPF-SG, 1228 g of KF-105, and 450 g of TSL9906 were weighed and added, and the mixture was stirred until the liquid temperature reached 140°C. Next, 12 g of DBU, 332 g of KF-105, and 128 g of TSL9906 were weighed, premixed until uniform, and then added dropwise to the flask using a dropping funnel. The viscosity, number average molecular weight (Mn), and weight average molecular weight (Mw) of Epoxy Resin 2 at 25°C are shown in Table 2. The viscosity at 25°C was measured using a rotational shear viscometer at 20 revolutions per minute.

[0093] (Synthesis of epoxy resin 3) Epoxy Resin 3 was obtained by the same reaction as in the synthesis of Epoxy Resin 1, except for the following changes in the amounts of each material. 480 g of terpene diphenol (YP-90, Yasuhara Chemical Co., Ltd.), 1145 g of KF-105, and 424 g of TSL9906 were weighed and added, and the mixture was stirred until the liquid temperature reached 140°C. Next, 20 g of DBU, 295 g of KF-105, and 115 g of TSL9906 were weighed and premixed until homogeneous. The mixture was then added dropwise to the flask using a dropping funnel. The viscosity at 25°C, number-average molecular weight (Mn), and weight-average molecular weight (Mw) of Epoxy Resin 3 are shown in Table 2. The viscosity at 25°C was measured using a rotational shear viscometer at 10 revolutions per minute.

[0094] [Table 2]

[0095] Epoxy resin 4: Bisphenol F type epoxy resin, epoxy equivalent 161g / eq Organic filler: Spherical silicone rubber particles with an average primary particle size of 0.1 μm, whose core contains cross-linked polydimethylsiloxane and whose shell contains polymethyl methacrylate. Hardener: Diethyltoluenediamine, active hydrogen equivalent 45g / eq Colorant: Carbon black Dispersant 1: Cationic dispersant Dispersant 2: Anionic dispersant Coupling agent: 3-glycidoxypropyltrimethoxysilane Antioxidant: Hindered phenolic antioxidant Ion trapping agent: Bismuth-based ion trapping agent Inorganic filler (a 1:4 (by mass) mixture of spherical silica with an average particle size of 0.5 μm and spherical silica with an average particle size of 4.2 μm) Solvent: Diethylene glycol monobutyl ether acetate

[0096] As is clear from the results in Table 1, the epoxy resin compositions of the Examples suppress the generation of voids when cured compared to the epoxy resin compositions of the Comparative Examples. Furthermore, the epoxy resin compositions of the Examples suppress the generation of warpage when cured to the same extent or more than the epoxy resin compositions of the Comparative Examples.

Claims

1. Contains an epoxy resin, a curing agent, a filler, and a solvent, The epoxy resin composition comprises a reaction product of a phenol compound represented by the following general formula (A) and a silicone-modified epoxy resin: 【Chemical 1】 (In general formula (A), R １ each independently represents an alkyl group or an aryl group, each X independently represents an alkylene group or an arylene group, p represents 1 or 2, each m independently represents an integer of 0 to 4, and n represents an integer of 0 to 4 when p is 1, and represents an integer of 0 to 3 when p is 2.

2. 2. The epoxy resin composition according to claim 1, wherein the content of the solvent is 1% by mass to 10% by mass.

3. 3. The epoxy resin composition according to claim 1, wherein the filler accounts for 40% by mass to 95% by mass of the solid content.

4. 4. The epoxy resin composition according to claim 1, wherein the filler contains an inorganic filler, and the proportion of the inorganic filler in the filler is 50% by mass to 99.9% by mass.

5. 5. The epoxy resin composition according to claim 1, wherein the curing agent comprises an amine-based curing agent.

6. The epoxy resin composition according to any one of claims 1 to 5, which is used for sealing a wafer-level chip size package.

7. An electronic component device comprising an element encapsulated with the epoxy resin composition according to any one of claims 1 to 6.

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