Liquid resin composition for compression molding and electronic component device

Abstract

The liquid resin composition for compression molding includes (A) aliphatic epoxy compounds, (B) epoxy compounds with aromatic rings in their molecules, (C) nitrogen-containing heterocyclic compounds, and (D) inorganic fillers.

Description

[Technical Field]

[0001] This invention relates to a liquid resin composition for compression molding and an electronic component device. [Previous Technology]

[0002] In recent years, in order to achieve lower cost, smaller size, thinner profile, lighter weight, higher performance, and higher functionality of electronic components, high-density mounting is being promoted through the miniaturization, multi-layering, and multi-pinning of component wiring and the miniaturization and thinning of packaging. Accompanying this, electronic components with roughly the same size as integrated circuits (ICs) are widely used, namely chip-size packages (CSPs).

[0003] Among these, wafer-level wafer-scale packaging (WLC) that involves resin sealing at the wafer stage has attracted attention. In this WLC, multiple components are simultaneously sealed and monolithically packaged using compression molding of a solid epoxy resin composition or printing molding of a liquid epoxy resin composition at the wafer stage. Therefore, compared to methods that seal components after monolithization, productivity can be significantly improved. However, sealed silicon wafers are prone to warping, which becomes a problem in subsequent handling, grinding, inspection, and monolithization steps, sometimes causing variations in component characteristics due to equipment limitations.

[0004] On the other hand, in the field of component sealing for electronic devices, resin sealing has been the mainstream in terms of productivity and cost, with epoxy resin compositions being widely used. The reason for this is that epoxy resin achieves a balance in various properties such as electrical properties, moisture resistance, heat resistance, mechanical properties, and adhesion to inserts. Silicon wafer warpage is considered to originate from stresses caused by the hardening shrinkage of the epoxy resin composition and the mismatch between the thermal expansion coefficients of the silicon wafer and the epoxy resin composition. Silicon wafer warpage can reduce the reliability of the package. Therefore, epoxy resin compositions used for this purpose require low stress. To reduce the stress of epoxy resin compositions, it is effective to use high-fill inorganic fillers to reduce the coefficient of thermal expansion and to use toughening agents (flexibilizers), flexible resins, etc., to reduce the elastic modulus.

[0005] For example, Patent Document 1 discloses a liquid epoxy resin composition for compression molding, which contains liquid bisphenol type epoxy resin, silicone rubber microparticles, silicone modified epoxy resin, aromatic amine curing agent, inorganic filler, and organic solvent. Patent Document 2 discloses a liquid epoxy resin composition for compression molding, which contains liquid epoxy resin, aromatic amine curing agent, microparticles of a core-shell silicone polymer comprising a core of a solid silicone polymer and a shell of an organic polymer, inorganic filler, and organic solvent. As described above, in the prior art, as a liquid resin composition for compression molding used to reduce the warpage of sealed silicon wafers, a liquid epoxy resin composition comprising at least liquid epoxy resin, curing agent, rubber microparticles, and inorganic filler is disclosed. Patent Document 3 discloses a liquid molding agent comprising epoxy resin, an anhydride curing agent, and inorganic filler. [Prior Art Documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 2007-23272 [Patent Document 2] Japanese Patent Application Publication No. 2008-150555 [Patent Document 3] Japanese Patent Application Publication No. 2014-152314 [Summary of the Invention]

[0007] [Problem to be Solved by the Invention] In Patent Document 1, which uses silicone rubber microparticles and silicone-modified epoxy resin, or in Patent Document 2, which uses microparticles of core-shell silicone polymers, the elastic modulus of the epoxy resin curing material can be reduced to achieve low stress. However, sometimes the warpage of even thinner silicon wafers or 12-inch or larger silicon wafers cannot be sufficiently reduced. In Patent Document 3, which uses an anhydride curing agent, the viscosity of the composition can be kept low, and the coefficient of linear expansion of the epoxy resin curing material can be reduced by filling a large amount of inorganic filler. However, sometimes the elastic modulus of the epoxy resin curing material is high, and the warpage of large silicon wafers cannot be sufficiently reduced. To achieve further cost reduction and thinner packaging, silicon wafers tend to have increasingly larger diameters and thinner thicknesses in the future, and it is necessary to reduce the warpage of these silicon wafers. It is believed that the warping problem of silicon wafers can occur in semiconductor wafers such as silicon carbide (SiC) wafers, sapphire wafers, and gallium arsenide (GaAs) wafers.

[0008] One aspect of the present invention is made in view of the aforementioned situation, and its object is to provide a liquid resin composition for compression molding that can suppress the occurrence of warpage in semiconductor wafers, and an electronic component device using the same. [Means for Solving the Problem]

[0009] One aspect of the present invention relates to the following: <1> A liquid resin composition for compression molding, comprising (A) an aliphatic epoxy compound, (B) an epoxy compound having an aromatic ring in its molecule, (C) a nitrogen-containing heterocyclic compound, and (D) an inorganic filler. <2> The liquid resin composition for compression molding as described in <1>, wherein the (A) aliphatic epoxy compound comprises a compound represented by the following general formula (I).

[0010] [Chemical 1]

[0011] [Where n is an integer from 1 to 15] <3> A liquid resin composition for compression molding as described in <1> or <2>, wherein the number of aliphatic epoxy compounds has an average molecular weight of 200 to 10,000. <4> A liquid resin composition for compression molding as described in any one of <1> to <3>, wherein the epoxy compound having an aromatic ring in its molecule comprises at least one of N,N-diglycidyl o-toluidine and N,N-bis(2,3-epoxypropyl)-4-(2,3-epoxypropoxy)aniline. <5> A liquid resin composition for compression molding as described in any one of <1> to <4>, comprising (E) a coupling agent. <6> An electronic component device comprising an element sealed by a liquid resin composition for compression molding as described in any one of <1> to <5>. [Effects of the Invention]

[0012] According to one aspect of the present invention, a liquid resin composition for compression molding that can suppress the warping of semiconductor wafers and an electronic component device using the same can be provided.

Implementation Method

[0013] Hereinafter, the embodiments for implementing the present invention will be described in detail. However, the present invention is not limited to the following embodiments. In the following embodiments, the constituent elements (including element steps, etc.) are not essential unless specifically stated otherwise. Similarly, numerical values ​​and their ranges are not limited to the present invention. In this disclosure, the numerical ranges represented by "~" contain numerical values ​​before and after "~", respectively, as the minimum and maximum values. In the numerical ranges described in stages in this disclosure, the upper or lower limit value described in one numerical range can also be replaced by the upper or lower limit value of other numerical ranges described in stages. Furthermore, in the numerical ranges described in this disclosure, the upper or lower limit value of that numerical range can also be replaced by the values ​​shown in the embodiments. In this disclosure, each component may also contain multiple equivalent substances. When multiple substances equivalent to each component exist in the composition, unless otherwise specified, the content or percentage of each component refers to the total content or percentage of the multiple substances present in the composition. In this disclosure, multiple particles equivalent to each component may also be included. Where multiple particles equivalent to each component are present in the composition, unless otherwise specified, the particle size of each component refers to the value of a mixture of the multiple particles present in the composition. In this disclosure, the terms "layer" or "film," when observing the region where the layer or film exists, include not only the case where it is formed entirely in the region, but also the case where it is formed only in a part of the region.

[0014] <Liquid Resin Composition for Compression Molding> The liquid resin composition for compression molding disclosed herein comprises (A) an aliphatic epoxy compound, (B) an epoxy compound having an aromatic ring in its molecule, (C) a nitrogen-containing heterocyclic compound, and (D) an inorganic filler. The liquid resin composition for compression molding disclosed herein may also contain other components besides those described above, if necessary. According to the liquid resin composition for compression molding disclosed herein, the generation of warpage in semiconductor wafers can be suppressed. The components constituting the liquid resin composition for compression molding will be described below.

[0015] - (A) Aliphatic epoxy compound - The liquid resin composition for compression molding includes (A) an aliphatic epoxy compound. In this disclosure, (A) an aliphatic epoxy compound refers to an aliphatic compound having at least one epoxy group in its molecule and no cyclic structures other than the epoxy group in its molecule. By including (A) an aliphatic epoxy compound in the liquid resin composition for compression molding, even when used in an embodiment where the liquid resin composition for compression molding is coated onto a semiconductor wafer and then cured, there is a tendency to more effectively suppress the generation of warpage in the semiconductor wafer.

[0016] As (A) aliphatic epoxy compound, a known or conventional aliphatic epoxy compound may be used, and there are no particular limitations. Specific examples of (A) aliphatic epoxy compounds include: monofunctional aliphatic epoxy compounds with 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.]; difunctional aliphatic epoxy compounds with two epoxy groups in the molecule, such as alkyl diglycidyl ether, poly(alkyl diol) diglycidyl ether, and olefinic diglycidyl ether; and polyfunctional aliphatic epoxy compounds with three or more epoxy groups in the molecule, such as polyglycidyl ethers of trifunctional or higher alcohols, such as trimethylolpropane, pentaerythritol, and dipentaerythritol [trimethylolpropane triglycidyl ether, pentaerythritol (tri- or tetra) glycidyl ether, dipentaerythritol (tri-, tetra-, penta-, or hexa-) glycidyl ether, etc.

[0017] Among them, as (A) the aliphatic epoxy compound, in terms of further effectively suppressing the warpage of the semiconductor wafer when a hardener is formed on the semiconductor wafer, it is preferably a difunctional aliphatic epoxy compound. More specifically, examples of difunctional aliphatic epoxy compounds include: ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, 1,3-propanediol diglycidyl ether, 2-methyl-1,3-propanediol diglycidyl ether, 2-butyl-2-ethyl-1,3-propanediol diglycidyl ether, 1,4-butanediol diglycidyl ether (tetramethylene glycol diglycidyl ether), neopentyl glycol diglycidyl ether, and 3-methyl-2,4-pentanediol diglycidyl ether. Ethers, 2,4-pentanediol diglycidyl ether, 1,5-pentanediol diglycidyl ether (pentamethylenediol diglycidyl ether), 3-methyl-1,5-pentanediol diglycidyl ether, 2-methyl-2,4-pentanediol diglycidyl ether, 2,4-diethyl-1,5-pentanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether (hexamethylenediol diglycidyl ether), 1,7-heptanediol diglycidyl ether, 3,5-heptanediol diglycidyl ether Oil ethers, 1,8-octanediol diglycidyl ether, 2-methyl-1,8-octanediol diglycidyl ether, 1,9-nonanediol diglycidyl ether, etc., alkanediol diglycidyl ethers (alkanediol diglycidyl ethers); diethylene glycol diglycidyl ether, triethylene glycol diglycidyl ether, tetraethylene glycol diglycidyl ether, dipropylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, poly(ethylene glycol / propylene glycol) diglycidyl ether, di- Tetramethylene glycol diglycidyl ether, tri-tetramethylene glycol diglycidyl ether, polytetramethylene glycol diglycidyl ether, di-pentamethylene glycol diglycidyl ether, tri-pentamethylene glycol diglycidyl ether, polypentamethylene glycol diglycidyl ether, di-hexamethylene glycol diglycidyl ether, tri-hexamethylene glycol diglycidyl ether, polyhexamethylene glycol diglycidyl ether, and other polyalkylene glycol diglycidyl ethers (including oligoalkylene glycol diglycidyl ethers), etc.

[0018] In particular, regarding the high suppression of semiconductor wafer warpage, in one embodiment, polyalkylene glycol diglycidyl ether is preferred, and more preferably, polyalkylene glycol diglycidyl ether having 1 to 20 alkylene glycol (alkylene glycol diglycidyl ether) units (especially alkylene glycol diglycidyl ether having 1 to 20 alkylene glycol units and 2 to 4 carbon atoms in the alkylene glycol units). Alternatively, as another embodiment, polyalkylene glycol diglycidyl ether having 2 to 20 alkylene glycol (alkylene glycol diglycidyl ether) units (especially alkylene glycol diglycidyl ether having 2 to 20 alkylene glycol units and 2 to 4 carbon atoms in the alkylene glycol units) may also be used.

[0019] (A) The molecular weight of the aliphatic epoxy compound (in the case of polymers, the number average molecular weight converted from standard polystyrene by gel permeation chromatography (GPC) using tetrahydrofuran as the dissolution solvent) is not particularly limited, but is preferably 200 to 10,000, more preferably 200 to 1,200, even more preferably 200 to 1,000, and particularly preferably 300 to 900. By setting the molecular weight (or number average molecular weight) of the aliphatic epoxy compound (A) within the aforementioned range, the tendency for warpage of semiconductor wafers can be suppressed more effectively.

[0020] More specifically, as (A) an aliphatic epoxy compound, a compound represented by the following general formula (I) (tetramethylene glycol diglycidyl ether or polytetramethylene glycol diglycidyl ether) is preferably exemplified. By using such a compound, the tendency of semiconductor wafer warpage can be more effectively suppressed.

[0021] [Chemical 2]

[0022] In the formula, n is an integer from 1 to 15.

[0023] In the liquid resin composition for compression molding, (A) the aliphatic epoxy compound may be used alone or in combination of two or more. Furthermore, as the compound represented by general formula (I), commercially available products such as "Epogose PT (normal grade)" (Yokakuichi Synthetic Co., Ltd., polytetramethylene glycol diglycidyl ether, quantity average molecular weight 700-800) may also be used.

[0024] The content of (A) aliphatic epoxy compound in the liquid resin composition for compression molding is not particularly limited, but is preferably 3% to 40% by mass, more preferably 5% to 35% by mass, and even more preferably 10% to 30% by mass, relative to the total amount of epoxy-containing compounds (all epoxy compounds; 100% by mass) in the liquid resin composition for compression molding. By setting the content of (A) aliphatic epoxy compound to 3% by mass or more, there is a tendency to further suppress the warpage of semiconductor wafers. On the other hand, by setting the content of (A) aliphatic epoxy compound to 40% by mass or less, there is a tendency to further improve the curability of the liquid resin composition for compression molding and further improve the heat resistance of the cured product.

[0025] -(B) Epoxy compound having an aromatic ring in the molecule- The liquid resin composition for compression molding includes an epoxy compound having an aromatic ring in the molecule of (B). As the epoxy compound having an aromatic ring in the molecule of (B), a known or conventional aromatic epoxy compound may be used, and there are no particular limitations. Specific examples of epoxy compounds having an aromatic ring in molecule (B) include: glycidyl ethers of phenols such as bisphenol A, bisphenol F, bisphenol AD, bisphenol S, catechol, and resorcinol; 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-xylenediamine; and epoxy compounds with a naphthalene skeleton such as glycidyl esters of naphthol and glycidyl ether esters of β-hydroxy esters of naphthol. Additionally, phenolic varnish compounds formed by phenolic varnishing of phenols such as phenol, catechol, and resorcinol can also be used. Among these, glycidylamine type epoxy compounds are preferred.

[0026] The epoxy compound containing an aromatic ring in molecule (B) of the liquid resin composition for compression molding is preferably a compound exhibiting a viscosity of 30 mPa·s to 5000 mPa·s at 25°C, and more preferably a viscosity of 30 mPa·s to 1000 mPa·s. If the viscosity of the epoxy compound containing an aromatic ring in molecule (B) is within this range, a composition suitable for compression molding can be obtained even when a large amount of inorganic filler (D) is incorporated into the liquid resin composition for compression molding. In this disclosure, the viscosity at 25°C refers to a value measured using a rotary shear viscometer equipped with a cone plate (48 mm in diameter, cone angle 1˚) at a shear rate of 10 rpm.

[0027] More specifically, N,N-bis(2,3-epoxypropyl)-4-(2,3-epoxypropoxy)aniline and N,N-diglycidyl o-toluidine are preferred examples of epoxy compounds having an aromatic ring in molecule (B). By using such compounds, there is a tendency to further improve the curability of liquid resin compositions for compression molding and further improve the heat resistance of the cured articles. When N,N-bis(2,3-epoxypropyl)-4-(2,3-epoxypropoxy)aniline and N,N-diglycidyl o-toluidine are used as epoxides having an aromatic ring in molecule (B), the content ratio of N,N-bis(2,3-epoxypropyl)-4-(2,3-epoxypropoxy)aniline and N,N-diglycidyl o-toluidine as a mass basis (N,N-bis(2,3-epoxypropyl)-4-(2,3-epoxypropoxy)aniline / N,N-diglycidyl o-toluidine) is preferably 0.5 to 13.0, more preferably 0.7 to 8.0, and even more preferably 1.0 to 3.5.

[0028] The content of the epoxy compound with an aromatic ring in the (B) molecule contained in the liquid resin composition for compression molding is not particularly limited, but is preferably 45% to 95% by mass, more preferably 55% to 90% by mass, and even more preferably 65% ​​to 85% by mass, relative to the total amount of epoxy compounds (all epoxy compounds; 100% by mass) contained in the liquid resin composition for compression molding. By setting the content of the epoxy compound with an aromatic ring in the (B) molecule to 45% by mass or more, there is a tendency to improve curability. On the other hand, by setting the content of the epoxy compound with an aromatic ring in the (B) molecule to 95% by mass or less, there is a tendency to suppress the warpage of semiconductor wafers. The content ratio ((A) aliphatic epoxy compound / (B) epoxy compound having an aromatic ring in the liquid resin composition for compression molding), which is a mass reference, is preferably 0.05 to 1.22, more preferably 0.11 to 0.82, and even more preferably 0.17 to 0.54.

[0029] - (C) Nitrogen-containing heterocyclic compound- The liquid resin composition for compression molding contains (C) a nitrogen-containing heterocyclic compound. As the (C) nitrogen-containing heterocyclic compound, any known or conventional nitrogen-containing heterocyclic compound may be used as long as it is used to polymerize (A) an aliphatic epoxy compound and (B) an epoxy compound having an aromatic ring in its molecule, and there are no particular limitations. Specific examples of nitrogen-containing heterocyclic compounds (C) include: 2-methylimidazolium, 2-undecylimidazolium, 2-heptadecylimidazolium, 2-ethyl-4-methylimidazolium, 2-phenylimidazolium, 2-phenyl-4-methylimidazolium, 2,4-diamino-6-[2'-methylimidazolyl-(1')]ethyl-triazine, 2-phenyl-4,5-dihydroxymethylimidazolium, 2-phenyl-4-methyl-5-hydroxymethylimidazolium, 2,3-dihydro-1H-pyrrolo[1,2-a]benzimidazole, etc.; and diazabicycloundecylene. (c) DBU-phenolic salts; DBU-octanoate; DBU-p-toluenesulfonate; DBU-formate; DBU-phthalate; DBU-phenolic varnish resin salts; DBU-tetraphenylboronic acid ester salts; Diazabicyclononene (DBN); DBN-phenolic varnish resin salts; Diazabicyclooctane; pyrazole; oxazole; thiazole; imidazoline; pyrazine; morpholine; thiazine; indole; isoindole; benzimidazole; purine; quinoline; isoquinoline; quinoxaline; cinnamon; pteridine, etc. (c) Nitrogen-containing heterocyclic compounds may be obtained by addition or microencapsulation with epoxy resin or isocyanate resin. Of these, 2-phenyl-4-methylimidazolium is preferred from the viewpoint of reactivity and storage stability.

[0030] Relative to the total of 100 parts by mass of (A) aliphatic epoxy compound, (B) epoxy compound having an aromatic ring in its molecule, and other epoxy compounds used as needed, the amount of (C) nitrogen-containing heterocyclic compound is preferably 2 to 20 parts by mass, more preferably 3 to 12 parts by mass. If the amount of (C) nitrogen-containing heterocyclic compound is 2 parts by mass or more, the curing time of the liquid resin composition for compression molding will not become too long, and the productivity of electronic component devices tends to be improved. If the amount of (C) nitrogen-containing heterocyclic compound is 20 parts by mass or less, the storage stability of the liquid resin composition for compression molding tends to be improved. Furthermore, without impairing the effects of the present invention, curing agents such as liquid anhydrides, liquid phenols, and aromatic amines may be used as needed. In this case, relative to 1 equivalent of epoxy compound in the liquid resin composition for compression molding, the amount of curing agent other than (C) nitrogen-containing heterocyclic compound is preferably less than 0.1 equivalent.

[0031] -(D) Inorganic filler- The liquid resin composition for compression molding includes an inorganic filler (D). Known or conventional inorganic fillers can be used as the inorganic filler (D), and there are no particular limitations. Examples of inorganic fillers (D) include: fused silica, crystalline silica, and other silica powders; powders of calcium carbonate, clay, alumina, silicon nitride, silicon carbide, boron nitride, calcium silicate, potassium titanate, aluminum nitride, beryllium oxide, zircon, forsterite, steel, spinel, mullite, titanium oxide, etc.; beads formed by spheroidizing these; glass fiber, etc. Furthermore, examples of inorganic fillers with flame-retardant effects include: aluminum hydroxide, magnesium hydroxide, zinc borate, zinc molybdate, etc. One of these inorganic fillers (D) can be used alone, or two or more can be used in combination. From the viewpoint of reducing the coefficient of linear expansion, fused silica is preferred, and from the viewpoint of high thermal conductivity, alumina is preferred. From the viewpoint of high filling capacity of (D) inorganic filler and its flowability and permeability in the fine gaps of the liquid resin composition for compression molding, the shape of (D) inorganic filler is preferably spherical.

[0032] Especially in the case of spherical silicon dioxide, the average particle size of the inorganic filler (D) is preferably 1 μm to 20 μm, more preferably 1.5 μm to 15 μm, and even more preferably 2 μm to 10 μm. Here, the average particle size refers to the particle size at which the volumetric cumulative particle size distribution, as measured by laser diffraction, reaches 50%. If the average particle size of the inorganic filler (D) is 1 μm or more, there is a tendency to easily disperse the inorganic filler (D) at a high concentration in the liquid resin composition for compression molding. If the average particle size of the inorganic filler (D) is 20 μm or less, there is a tendency for the coarse particle component of the inorganic filler (D) to decrease, suppressing inadequate filling in the fine gaps of the liquid resin composition for compression molding or streaks during printing, and improving surface smoothness.

[0033] Relative to the total amount of the liquid resin composition for compression molding, the content of inorganic filler (D) is preferably set to a range of 73% to 93% by mass, and more preferably to a range of 78% to 91% by mass. If the content of inorganic filler (D) is 73% by mass or more, there is a tendency to obtain a reduction in the coefficient of thermal expansion of the cured liquid resin composition for compression molding and a reduction in warpage. If the content of inorganic filler (D) is 93% by mass or less, there is a tendency to suppress the increase in viscosity of the liquid resin composition for compression molding and to improve the coating workability.

[0034] -(E) Coupling Agent- To ensure strong adhesion between the resin and inorganic fillers or between the resin and constituent components of electronic parts, the liquid resin composition for compression molding may, as needed, include a (E) coupling agent. Known or conventional (E) coupling agents may be used, and there are no particular limitations. Examples of (E) coupling agents include: silane compounds having at least one selected from the group consisting of primary, secondary, and tertiary amino groups; various silane compounds such as epoxy silanes, mercaptosilanes, alkyl silanes, urea silanes, and vinyl silanes; titanium compounds; aluminum chelates; aluminum / zirconium compounds, etc.Examples of coupling agents (E) include: vinyltrichlorosilane, vinyltriethoxysilane, vinyltri(β-methoxyethoxy)silane, γ-methacryloxypropyltrimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, vinyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropylmethyldimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropylmethyldiethoxysilane, γ-anilinopropyltrimethoxysilane, γ-anilinopropyltriethoxysilane. γ-(N,N-dimethyl)aminopropyltrimethoxysilane, γ-(N,N-diethyl)aminopropyltrimethoxysilane, γ-(N,N-dibutyl)aminopropyltrimethoxysilane, γ-(N-methyl)anilinepropyltrimethoxysilane, γ-(N-ethyl)anilinepropyltrimethoxysilane, γ-(N,N-dimethyl)aminopropyltriethoxysilane, γ-(N,N-diethyl)aminopropyltriethoxysilane, γ-(N,N-dibutyl)aminopropyltriethoxysilane, γ-(N-methyl)anilinepropyltriethoxysilane, γ-(N-ethyl)anilinepropyltriethoxysilane, γ-(N,N-dimethyl)aminopropylmethyldimethoxysilane Silane-based coupling agents including γ-(N,N-diethyl)aminopropylmethyldimethoxysilane, γ-(N,N-dibutyl)aminopropylmethyldimethoxysilane, γ-(N-methyl)anilinepropylmethyldimethoxysilane, γ-(N-ethyl)anilinepropylmethyldimethoxysilane, N-(trimethoxysilylpropyl)ethylenediamine, N-(dimethoxymethylsilylisopropyl)ethylenediamine, methyltrimethoxysilane, dimethyldimethoxysilane, methyltriethoxysilane, γ-chloropropyltrimethoxysilane, hexamethyldisilane, vinyltrimethoxysilane, γ-mercaptopropylmethyldimethoxysilane, etc.; isopropyltriisostearyl titanate; isopropyltris(dioctylpyrophosphorus) Titanium ester coupling agents include isopropyltris(N-aminoethyl-aminoethyl) titanate, tetraoctylbis(di-decayl phosphite) titanate, tetra(2,2-diallyloxymethyl-1-butyl)bis(di-decayl phosphite) titanate, bis(dioctyl pyrophosphate)oxyacetic acid titanate, bis(dioctyl pyrophosphate) vinyl titanate, isopropyltrioctyl titanate, isopropyl dimethacrylate isostearyl titanate, isopropyltri-dodecylbenzenesulfonyl titanate, isopropyl isostearyl diacrylate titanate, isopropyltris(dioctyl phosphate) titanate, isopropyltricumylphenyl titanate, and tetraisopropylbis(dioctyl phosphite) titanate. These (E) coupling agents can be used alone or in combination of two or more.

[0035] When the liquid resin composition for compression molding contains (E) coupling agent, the content of (E) coupling agent is preferably 0.1% to 2.0% by mass, more preferably 0.2% to 1.5% by mass, relative to the total amount of (D) inorganic filler and (E) coupling agent. If the content of (E) coupling agent is 0.1% by mass or more, it tends to easily obtain the effect of improving the dispersibility of (D) inorganic filler brought about by (E) coupling agent. If the content of (E) coupling agent is 2.0% by mass or less, it tends to be difficult to generate voids in the hardened form of the liquid resin composition for compression molding.

[0036] - (F) Organic Solvent - The liquid resin composition for compression molding may also contain an organic solvent (F) as needed. Known or conventional organic solvents (F) may be used as the organic solvent, and there are no particular limitations. When the liquid resin composition for compression molding contains an organic solvent (F), the content of the organic solvent (F) is preferably less than 5% by mass relative to the total amount of components (A) to (F). If the content of the organic solvent (F) is less than 5% by mass, there is a tendency to suppress the reduction of film after curing.

[0037] -Other Components- The liquid resin composition for compression molding may, as needed, contain other components besides components (A) to (F). The liquid resin composition for compression molding may also contain epoxy compounds other than (A) aliphatic epoxy compounds and (B) epoxy compounds having aromatic rings in their molecules. As other epoxy compounds, known or conventional epoxy compounds other than (A) aliphatic epoxy compounds and (B) epoxy compounds having aromatic rings in their molecules may be used, and there are no particular limitations. When the liquid resin composition for compression molding contains other epoxy compounds, the content of other epoxy compounds is preferably more than 0% by mass and less than 40% by mass, more preferably more than 0% by mass and less than 30% by mass, and even more preferably more than 0% by mass and less than 20% by mass, relative to the total amount of epoxy-containing compounds (all epoxy compounds; 100% by mass) contained in the liquid resin composition for compression molding.

[0038] From the viewpoint of improving the migration resistance, moisture resistance, and high-temperature storage characteristics of semiconductor devices such as ICs, the liquid resin composition for compression molding preferably includes an ion scavenger as another component. There are no particular limitations on the ion scavenger, and known or conventionally used ones can be used. Examples of ion scavengers include hydrotalcite, hydrated oxides of elements such as magnesium, aluminum, titanium, zirconium, and bismuth. These ion scavengers can be used alone or in combination of two or more. Specifically, examples include DHT-4A (Kyowa Chemical Industry Co., Ltd., trade name) and IXE500 (Toa Synthetic Co., Ltd., trade name). The content of the ion scavenger in the liquid resin composition for compression molding is not particularly limited as long as it is sufficient to capture anions such as halide ions and cations such as sodium; it is preferably 1% to 10% by mass relative to the total amount of epoxy compound.

[0039] The liquid resin composition for compression molding preferably includes, as needed, a curing accelerator; colorants such as dyes, pigments, and carbon black; silicone oil; surfactants; antioxidants; phosphate esters; nitrogen-containing compounds such as melamine, melamine derivatives, compounds having a triazine ring, cyanuric acid derivatives, and isocyanuric acid derivatives; phosphorus-nitrogen-containing compounds such as cyclophosphonitriles; metal compounds such as zinc oxide, iron oxide, molybdenum oxide, and ferrocene; antimony oxides such as antimony trioxide, antimony tetroxide, and antimony pentoxide; and previously known flame retardants such as brominated epoxy resins, etc.

[0040] Liquid resin compositions for compression molding can be prepared by any method as long as the various components can be uniformly dispersed and mixed. Common methods for preparing liquid resin compositions for compression molding include weighing a predetermined amount of the components and dispersing and mixing them using a three-roll mill, grinding mixer, planetary mixer, hard mixer, homogenizer, etc. Furthermore, in terms of uniform dispersibility and flowability, a method using a masterbatch prepared by pre-dispersing and pre-heating the various components is preferred.

[0041] The curing conditions for the liquid resin composition for compression molding disclosed herein are not particularly limited. The heat treatment temperature is preferably 120°C to 200°C, more preferably 130°C to 180°C, and even more preferably 140°C to 170°C. The heat treatment time is preferably 15 minutes to 3 hours, more preferably 30 minutes to 2 hours.

[0042] The glass transition temperature of the cured liquid resin composition for compression molding disclosed herein, as determined by dynamic mechanical analysis (DMA), is preferably 125°C or higher, more preferably 150°C or higher. The modulus of elasticity of the cured liquid resin composition for compression molding disclosed herein at a temperature below the glass transition temperature determined by DMA is preferably 20 GPa or lower, more preferably 16 GPa or lower. The coefficient of linear expansion of the cured liquid resin composition for compression molding disclosed herein at a temperature below the glass transition temperature is preferably 15 ppm / °C or lower, more preferably 12 ppm / °C or lower. The viscosity of the liquid resin composition for compression molding disclosed herein at 25°C is preferably less than 1000 Pa∙s, more preferably 800 Pa∙s or lower, and even more preferably 500 Pa∙s or lower.

[0043] <Electronic Component Device> The electronic component device disclosed herein includes components sealed with the liquid resin composition for compression molding disclosed herein. Examples of electronic component devices include those obtained in the following manner: electronic components such as semiconductor wafers, transistors, diodes, thyristors, capacitors, resistors, resistor arrays, coils, and switches are mounted on supporting components such as lead frames, wire carriers with completed wiring, wiring boards, glass, and silicon wafers; and the necessary parts are sealed using the liquid resin composition for compression molding disclosed herein. The liquid resin composition for compression molding disclosed herein is effective for electronic component devices requiring low warpage and high reliability, and is particularly suitable for wafer-level chip-scale packaging. Methods for sealing components using the liquid resin composition for compression molding disclosed herein include dispensing methods, casting methods, and printing methods; printing is particularly suitable. [Example]

[0044] The present invention has been described through embodiments, but the present invention is not limited to the following embodiments. Furthermore, in the following embodiments, unless otherwise specified, parts and % represent parts by mass and percentage by mass.

[0045] (Examples 1, 2, and Comparative Example 1) The materials shown in Table 1 were mixed for 2 hours using a planetary mixer, and then stirred and degassed for 1 hour using a hard mixer under a vacuum of 80 Pa to 90 Pa to produce a liquid resin composition for compression molding. In Table 1, components (A), (B), (C), and (D) refer to (A) an aliphatic epoxy compound, (B) an epoxy compound having an aromatic ring in its molecule, (C) a nitrogen-containing heterocyclic compound, and (D) an inorganic filler, respectively. Furthermore, the units for the composition of each component listed in Table 1 are parts by mass.

[0046] The manufactured liquid resin composition for compression molding was evaluated by the following tests. The results are summarized in Table 1.

[0047] (Viscosity and Hydraulic Index) The viscosity of the manufactured liquid resin composition for compression molding was measured at 25°C and 10 rpm using a Brookfield HB viscometer. If the viscosity at 25°C is less than 1000 Pa∙s, high productivity can be achieved using conventional compression molding equipment. The hydraulic index is defined as the value obtained by dividing the viscosity measured at 25°C and 1 rpm for the liquid resin composition for compression molding by the viscosity measured at 25°C and 10 rpm.

[0048] (Coefficient of Linear Expansion) For the cured product obtained by heating and curing a liquid resin composition for compression molding at 150°C for 60 minutes, the coefficient of linear expansion was measured at 50°C–70°C and 180°C–200°C using a Bruker ASX TMA4000SA series thermomechanical analysis method. If the coefficient of linear expansion at temperatures below Tg is 12 ppm / °C or less, the warpage of the semiconductor wafer can be sufficiently reduced.

[0049] (Glass transition temperature (Tg) and elastic modulus) For the cured material obtained by heating and curing a liquid resin composition for compression molding at 150°C for 60 minutes, the glass transition temperature and elastic modulus were measured using a DMS6100 from SII Corporation and by the DMA (Dynamic Mechanical Analysis) method. If the glass transition temperature is 140°C or higher, a semiconductor device with high reliability can be obtained. Furthermore, if the elastic modulus at a temperature below Tg is 20 GPa or lower, a semiconductor wafer with low warpage is suitable.

[0050] (Warpage) A compression molding liquid resin composition layer with a diameter of 292 mm and a thickness of 300 μm was formed on a silicon wafer with a diameter of 300 mm and a thickness of 300 μm using a mold, and then heated and hardened at 150°C for 60 minutes to form a sample. After hardening, the height difference between the center and the end of the silicon wafer was measured using a ruler to define warpage.

[0051] [Table 1] Material Name Example 1 Example 2 Comparative Example 1 (A) Ingredients Epoxy resin （ 1 ） 3.2 2.1 - (B) Components Epoxy resin （ 2 ） 11.5 7.7 - Epoxy resin （ 3 ） 3.7 2.5 - Epoxy resin （ 4 ） - - 4.5 (C) Components imidazole （ 5 ） 0.7 0.5 0.6 hardener acid anhydride （ 6 ） - - 7.5 (D) Component Silica filler （ 7 ） - 68.0 68.0 Silica filler （ 8 ） - 17.0 17.0 Silica filler （ 9 ） 78.0 - - Other ingredients Silane coupling agent （ 10 ） 0.2 0.2 0.2 carbon black （ 11 ） 0.2 0.2 0.2 Silicon oil （ 12 ） 2.5 1.8 2.0 total 100.0 100.0 100.0 Viscosity (Pa∙s) twenty three 288 245 Shaking index 0.8 0.8 1.1 Glass transfer temperature (°C) 160 168 145 Coefficient of linear expansion (ppm / ℃) <Tg 11 7 8 >Tg 30 18 36 Elastic modulus (GPa) <Tg 9.0 11.6 16.4 Warp (mm) 0 0 8

[0052] The details of each material in (1) to (12) in Table 1 are as follows. In addition, in Table 1, "-" means that no equivalent material is used. (1) Yokkaichi Synthetic Co., Ltd., Polytetramethylene glycol diglycidyl ether (Product name: Epigose PT (normal grade), epoxy equivalent 440 g / eq, average molecular weight 880) (2) Mitsubishi Chemical Co., Ltd., Aminophenol type epoxy compound (Product name: jER 630, epoxy equivalent 95 g / eq, average molecular weight 285, viscosity at 25℃: 700 mPa·s, compound name: N,N-bis(2,3-epoxypropyl)-4-(2,3-epoxycyclopropyl)aniline) (3) ADEKA Co., Ltd., Toluidine type epoxy compound (Product name: EP3980S, epoxy equivalent 135 g / eq, average molecular weight 270, viscosity at 25℃: 50 mPa·s, compound name: N,N-diglycidyl o-toluidine) (4) DIC Corporation, Naphthalene-type epoxy compound (product name: HP4032D, epoxy equivalent 140 g / eq, average molecular weight 280) (5) Shikoku Chemical Co., Ltd., Imidazole compound (product name: Curezol 2P4MZ) (6) Hitachi Chemical Co., Ltd., Methylhexahydrophthalic anhydride (product name: HN2200) (7) Nippon Steel & Sumitomo Metal Materials Co., Ltd., Spherical silicon dioxide (product name: STW7010-20, average particle size 10 μm) (8) Admatechs Co., Ltd., Spherical silicon dioxide (product name: SE2300, average particle size 0.6 μm) (9) Admatechs Co., Ltd., Spherical silicon dioxide (product name: 2umSM-E4, average particle size 2 μm) (10) Shin-Etsu Chemical Industry Co., Ltd., Silane Coupling Agent (Product Name: KBM403, Compound Name: γ-glycidoxypropyltrimethoxysilane) (11) Orion Engineered Carbons Co., Ltd., Carbon Black (Product Name: Special Black 4) (12) Toray Dow Corning Co., Ltd., Silicon Oil (Product Name: SF8421)

[0053] Furthermore, the average particle size of all the silica fillers contained in Example 2 and Comparative Example 1 is 8 μm.

[0054] According to Table 1, in Examples 1 and 2, although the viscosity, glass transition temperature, coefficient of linear expansion, and elastic modulus were within practical ranges, the warpage of the silicon wafer was 0 mm. In contrast, in Comparative Example 1, which uses an anhydride curing agent, the warpage was as large as 8 mm.

[0055] As described above, by using the liquid resin composition for compression molding disclosed herein, multiple devices can be sealed in batches for even thinner silicon wafers or large silicon wafers of 12 inches or larger. Furthermore, it is believed that when the liquid resin composition for compression molding disclosed herein is applied to compound semiconductor wafers such as silicon carbide (SiC) wafers, sapphire wafers, and gallium arsenide (GaAs) wafers, the generation of warpage in semiconductor wafers can also be suppressed.

[0056] The entire disclosure of Japanese Patent Application No. 2017-108716, filed on May 31, 2017, is incorporated herein by reference. Furthermore, all documents, patent applications, and technical specifications described in this specification are incorporated herein by reference to the same extent as those specifically and individually described and incorporated herein by reference.

Claims

1. A liquid resin composition for compression molding, comprising (A) an aliphatic epoxy compound, (B) an epoxy compound having an aromatic ring in its molecule, (C) a nitrogen-containing heterocyclic compound and (D) an inorganic filler, wherein the (A) aliphatic epoxy compound comprises a compound represented by the following general formula (I); , [where n is an integer from 1 to 15].

2. The liquid resin composition for compression molding as described in claim 1, wherein the number of aliphatic epoxy compounds (A) has an average molecular weight of 200 to 10,000.

3. The liquid resin composition for compression molding as described in claim 1 or 2, comprising (E) a coupling agent.

4. An electronic component device comprising an element sealed with a compression-molded liquid resin composition as described in any one of claims 1 to 3.