Epoxy resin composition, semiconductor device, and method for producing semiconductor device

Abstract

The invention provides an epoxy resin composition capable of achieving both injectability and reliability, a semiconductor device, and a method for manufacturing the semiconductor device. The epoxy resin composition contains a polyalkylene glycol type epoxy resin, a nitrogen atom-containing heterocyclic compound, and a filler. The content of the filler is 55% by mass or more and less than 77% by mass relative to the total amount of the epoxy resin composition.

Description

Technical Field

[0001] One embodiment of the present disclosure relates to an epoxy resin composition, a semiconductor device, and a method for producing a semiconductor device. Background Art

[0002] Electronic devices having semiconductor devices are required to be smaller, lighter, and more functional. To meet such requirements, the mainstream method of mounting semiconductor devices has shifted from wire bonding to flip-chip mounting. Generally, for a semiconductor device mounted by flip chip mounting, several to several thousand bump electrodes with a height of about 10 μm to 100 μm are formed on a substrate. Electrode portions on the substrate and semiconductor elements are connected via the bump electrodes.

[0003] For semiconductor devices mounted by flip chip mounting, cracks and other defects may occur in bump electrodes when thermal loads such as temperature cycling are applied. This is because there is a difference in the linear expansion coefficient of the substrate containing a large amount of organic materials such as epoxy resin and the linear expansion coefficient of the semiconductor element containing a large amount of metal materials, so stress is applied to the bump electrodes. In order to prevent cracks, the following method is widely used. That is, the gap between the substrate and the semiconductor element is filled with a liquid semiconductor sealing material called an underfill (also called an underfill material, sealing material). Then, the corner (corner end) of the chip forms a portion called a fillet where the semiconductor sealing material is piled up. By sealing in this way, the resistance to heat load (heat cycle resistance) and the chip protection from heat and external forces can be improved.

[0004] The sealing material is generally a composition containing an epoxy resin and a filler. As an example of a sealing material, a sealing material containing an aminophenol-type epoxy resin, an amine-based curing agent, a silica filler, and a silane coupling agent has been proposed (for example, see Patent Document 1). In addition, a sealing material containing an epoxy resin, a curing agent, a filler, and a modified polysiloxane has been proposed (for example, see Patent Document 2). Various sealing materials have been proposed by changing the type of epoxy resin, the type of curing agent, and the like in this manner. Prior art literature Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2016-113525 Patent Document 2: Japanese Patent Application Publication No. 2001-55488 Summary of the invention Technical problem to be solved by the invention

[0006] In recent years, semiconductor devices have been required to be more compact, lightweight, and have higher performance. As a result, the wiring in semiconductor devices has become more dense. That is, the fine pitch of wiring patterns on substrates in semiconductor devices (the spacing between wirings is narrowed, so-called narrowing) is developing. Therefore, an underfill material that can be used even for fine pitches is required.

[0007] On the other hand, in order to reduce the difference in linear expansion coefficient between the chip and the bump, the existing bottom filling material contains fillers. If the bottom filling material contains a large amount of fillers, the viscosity increases. In particular, if the bottom filling material contains a large amount of fine fillers, the viscosity increases significantly. In addition, if the bottom filling material contains coarse fillers, the volume of the coarse fillers may cause the bottom filling material to be unable to enter the gap of the fine-pitch wiring pattern. As described above, it is sometimes difficult to inject the underfill material into the gaps between fine-pitch wiring patterns with conventional underfill materials. Therefore, there is a need to improve the injectability of the underfill material.

[0008] In response to this, attempts have been made to reduce the viscosity of the underfill material by reducing the filler content in the underfill material, but if the filler content is reduced, reliability may be reduced, wherein the reliability is related to heat cycle resistance such as fillet cracks, and moisture absorption reflow, etc.

[0009] An object of the present disclosure is to provide an epoxy resin composition, a semiconductor device, and a method for manufacturing a semiconductor device that can achieve both good injectability and reliability. Technical means to solve technical problems

[0010] The present inventors studied the composition of an appropriate underfill material when injecting an underfill material into a substrate having a fine-pitch wiring pattern. At this time, the inventors considered that if the filler content of the epoxy resin composition is reduced, the reliability related to heat cycle resistance and moisture absorption reflow, etc. is reduced; and if the filler content is increased, the viscosity of the underfill material increases, the injectability is reduced, and voids are generated in the injected portion. As a result, they found that an underfill material having both injectability and reliability can be realized by using a polyalkylene glycol epoxy resin having flexibility as an epoxy resin, a filler, and an appropriate curing agent component.

[0011] Specifically, in order to achieve the above-mentioned purpose, an epoxy resin composition according to an embodiment of the present disclosure contains an epoxy resin, a heterocyclic compound containing a nitrogen atom, and a filler, wherein: The epoxy resin contains at least a polyalkylene glycol type epoxy resin, The content of the filler is 55 mass % or more and less than 77 mass % based on the total amount of the epoxy resin composition. Beneficial Effects

[0012] According to one embodiment of the present disclosure, an epoxy resin composition, a semiconductor device, and a method for manufacturing a semiconductor device that can achieve both injectability and reliability can be provided. DETAILED DESCRIPTION

[0013] (Epoxy resin composition) The epoxy resin composition of the embodiment contains a polyalkylene glycol epoxy resin, a nitrogen-containing heterocyclic compound, and a filler. The epoxy resin composition of the embodiment preferably further contains an epoxy resin other than the polyalkylene glycol epoxy resin and a phenolic curing agent, and contains other components as needed.

[0014] <Polyalkylene glycol type epoxy resin> The polyalkylene glycol epoxy resin is contained in order to achieve both injectability and reliability. The polyalkylene glycol epoxy resin has no rigid ring in the molecule and is composed only of a soft structure, i.e., a linear structure. Therefore, the polyalkylene glycol epoxy resin is a resin with a high stress relaxation effect, has softness, can give flexibility to the cured product, and can reduce the elastic modulus of the cured product. Therefore, the injectability and reliability of the epoxy resin composition can be taken into account while maintaining the amount of filler at a certain amount.

[0015] Examples of the polyalkylene glycol epoxy resin include polytetramethylene glycol epoxy resin, polyethylene glycol epoxy resin, and polypropylene glycol epoxy resin, etc. These may be used alone or in combination of two or more. Among these, polytetramethylene glycol type epoxy resins are preferred from the viewpoint of injectability and stress relaxation.

[0016] Regarding the molecular weight of the polyalkylene glycol epoxy resin, from the viewpoint of the balance between viscosity and flexibility, the weight average molecular weight is preferably 500 to 3,000, and more preferably 1,500 to 2,500. In this specification, the weight average molecular weight refers to the value obtained by gel permeation chromatography (GPC) using a calibration curve based on standard polystyrene. If the weight average molecular weight is less than 500, the effect of flexibility is small, so the reliability may be deteriorated. On the other hand, if the weight average molecular weight is more than 3,000, the epoxy resin composition becomes high viscosity and the injectability may be deteriorated.

[0017] The number of epoxy groups contained in one molecule of the polyalkylene glycol epoxy resin is not particularly limited and can be appropriately selected according to the purpose, and is preferably 2 or more (multifunctional epoxy resin) from the viewpoint of reliability. The upper limit of the number of epoxy groups is not particularly limited and can be appropriately selected according to the purpose, and is preferably 5 or less.

[0018] The polyalkylene glycol type epoxy resin may contain chlorine, which is a by-product, during synthesis. When chlorine is contained in the resin, injectability and reliability may be reduced. Therefore, the chlorine content of the polytetramethylene glycol type epoxy resin is preferably 1,000 ppm or less.

[0019] The polyalkylene glycol type epoxy resin is preferably used in combination with an epoxy resin other than the polyalkylene glycol type epoxy resin described below.

[0020] The content of the polyalkylene glycol epoxy resin is preferably 10% to 30% by mass, more preferably 15% to 20% by mass, relative to the epoxy resin. If the content of the polyalkylene glycol epoxy resin is less than 10% by mass, the stress relaxation effect becomes insufficient and the reliability may deteriorate. On the other hand, if the content of the polyalkylene glycol epoxy resin is greater than 30% by mass, the cured product of the epoxy resin composition becomes brittle, and thus the reliability may be reduced.

[0021] <Other epoxy resins> The other epoxy resins are epoxy resins other than the above-mentioned polyalkylene glycol epoxy resins. The other epoxy resins can be used without particular limitation as long as they are various epoxy resins commonly used for semiconductor sealing. The number of epoxy groups contained in one molecule of other epoxy resins is not particularly limited and can be appropriately selected according to the purpose, and is preferably 2 or more (multifunctional epoxy resin) from the viewpoint of reliability. The upper limit of the number of epoxy groups is not particularly limited and can be appropriately selected according to the purpose, and is preferably 5 or less. The epoxy equivalent of the other epoxy resin is preferably 50 g / eq. to 10,000 g / eq., more preferably 50 g / eq. to 1,000 g / eq., and even more preferably 100 g / eq. to 500 g / eq. Here, the epoxy equivalent is the mass of a resin containing 1 equivalent of epoxy groups, as defined in JIS K 7236: 2001. In addition, "eq." is an abbreviation for "equivalent".

[0022] Examples of epoxy resins other than polyalkylene glycol epoxy resins include glycidylamine epoxy resins, aliphatic epoxy resins, alicyclic epoxy resins, bisphenol epoxy resins, novolac epoxy resins, fluorene epoxy resins, biphenyl epoxy resins, aminophenol epoxy resins, and naphthalene epoxy resins. Examples of the glycidylamine epoxy resin include diglycidylaniline, diglycidyltoluidine, tetraglycidyl-m-xylylenediamine, and tetraglycidylbis(aminomethyl)cyclohexane. Examples of the alicyclic epoxy resin include vinyl (3,4-cyclohexene) dioxide and 2-(3,4-epoxycyclohexyl)-5,1-spiro-(3,4-epoxycyclohexyl)-m-dioxane. Examples of the bisphenol epoxy resin include bisphenol A epoxy resin and bisphenol F epoxy resin. Examples of the bisphenol A epoxy resin include p-glycidyloxyphenyl dimethyl tribisphenol A diglycidyl ether. Examples of the biphenyl type epoxy resin include biphenyl aralkyl epoxy resin and 3,3′,5,5′-tetramethyl-4,4′-diglycidyloxybiphenyl. Examples of the aminophenol-type epoxy resin include triglycidyl-p-aminophenol and the like. Furthermore, the number of epoxy groups in the epoxy resin may be 1 (monofunctional) or 2 or more (polyfunctional). Examples of the monofunctional epoxy resin include p-tert-butylphenyl glycidyl ether and the like. Examples of the polyfunctional epoxy resin include diepoxy resins such as 1,4-phenyl dimethanol diglycidyl ether; and triepoxy resins such as trimethylolpropane triglycidyl ether and glycerol triglycidyl ether. Epoxy resins other than polyalkylene glycol type epoxy resins may be, in addition to the above, hydantoin type epoxy resins such as 1,3-diglycidyl-5-methyl-5-ethylhydantoin; epoxy resins having a silicone skeleton such as 1,3-bis(3-glycidyloxypropyl)-1,1,3,3-tetramethyldisiloxane; and epoxy resins having a skeleton derived from plants. They can be used alone or in combination of two or more. Among these, from the viewpoint of reliability, glycidylamine epoxy resin, bisphenol epoxy resin, and aliphatic epoxy resin are preferred. That is, the epoxy resin composition preferably further contains at least one selected from glycidylamine epoxy resin, bisphenol epoxy resin, and aliphatic epoxy resin. In addition, aliphatic epoxy resin and aromatic epoxy resin are more preferably used in combination.

[0023] The content of the epoxy resin (the total amount of the polyalkylene glycol epoxy resin and other epoxy resins) is not particularly limited and can be appropriately selected according to the purpose, and is preferably 45% to 23% by mass relative to the total amount of the epoxy resin composition. If the content of the epoxy resin is within this range, both injectability and reliability can be achieved.

[0024] <Heterocyclic Compounds Containing Nitrogen Atoms> The heterocyclic compound containing nitrogen atoms is contained in order to cure the epoxy resin composition. When the epoxy resin composition is cured, the heterocyclic compound containing nitrogen atoms and the epoxy resin are homopolymerized. In contrast, the amine curing agent and the epoxy resin are addition polymerized. The difference in the above reactions allows the heterocyclic compound containing nitrogen atoms to cure with a lower crosslinking density and linear expansion coefficient than the amine curing agent. Therefore, by using a nitrogen-containing heterocyclic compound as a curing agent, the linear expansion coefficient of the cured product of the epoxy resin composition can be reduced (particularly, the linear expansion coefficient of the cured product of the epoxy resin composition at a temperature above the glass transition point can be reduced). Thus, at high temperatures, the difference between the linear expansion coefficient of the cured product of the epoxy resin composition and the linear expansion coefficient of the chip becomes smaller, and the generated stress becomes further reduced. Therefore, the reliability can be improved.

[0025] The nitrogen-containing heterocyclic compound is not particularly limited as long as it can cure the resin in the epoxy resin composition, and can be appropriately selected according to the purpose. Examples of the heterocyclic compound include imidazole derivatives and microencapsulated nitrogen-containing heterocyclic compounds. Examples of imidazole derivatives include 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-ethyl-4-imidazole, 2-phenylimidazole, 1-benzyl-2-phenylimidazole, benzimidazole, 2,4-diamino-6-[2'-methylimidazolyl-(1')]ethyl-s-triazine, 2-phenyl-4,5-dihydroxymethylimidazole, and 2,3-dihydro-1H-pyrrolo[1,2-a]benzimidazole. These may be used alone or in combination of two or more. As imidazole derivatives, commercial products or appropriately synthesized products may be used. Examples of commercial products include 2P4MZ (2-phenyl-4-methylimidazole), 2MZA (2,4-diamino-6-[2'-methylimidazolyl-(1')]ethyl-s-triazine, and 2-phenyl-4-methylimidazole) (all manufactured by Shikoku Chemical Industries, Ltd.).

[0026] The nitrogen-containing heterocyclic compound may be a microencapsulated substance. As the microencapsulated nitrogen-containing heterocyclic compound, a commercially available product may be used, or a suitably synthesized product may be used. Commercially available products include, for example, Novacura HX3941HP, Novacura HXA3042HP, Novacura HXA3922HP, Novacura HXA3792, Novacura HX3748, Novacura HX3721, Novacura HX3722, Novacura HX3088, and Novacura HX3792. Ua HX3741, Novaqua HX3742, Novaqua HX3613 (all manufactured by Asahi Kasei Corporation), Amikura PN-23J, Amikura PN-40J (all manufactured by Ajinomoto Fujitech Co., Ltd.), and Fujiqua FXR-1121 (manufactured by Fuji Chemical Industries, Ltd.). These may be used alone or in combination of two or more.

[0027] Among these, from the viewpoint of reactivity and storage stability, the nitrogen-containing heterocyclic compound is preferably 2-phenyl-4-methylimidazole and 2,4-diamino-6-[2'-methylimidazolyl-(1')]ethyl-s-triazine. That is, the nitrogen-containing heterocyclic compound is preferably at least one selected from 2-phenyl-4-methylimidazole and 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine.

[0028] The content of the nitrogen-containing heterocyclic compound is not particularly limited and can be appropriately selected according to the purpose. Relative to the epoxy resin composition other than the filler described later, the content of the nitrogen-containing heterocyclic compound is preferably 2.0 mass % to 8.0 mass %, more preferably 2.5 mass % to 6.0 mass %. If the content of the nitrogen-containing heterocyclic compound is 2.0 mass % or more, the curing time of the epoxy resin composition can be accelerated, so the productivity of the electronic component device is improved. If the content of the nitrogen-containing heterocyclic compound is 8.0 mass % or less, the storage stability of the epoxy resin composition is improved. The content of the microencapsulated nitrogen-containing heterocyclic compound is preferably 3% to 25% by mass, more preferably 5% to 20% by mass, based on the epoxy resin composition excluding the filler as the active ingredient (nitrogen-containing heterocyclic compound).

[0029] <Packing> The filler is contained in order to reduce the linear expansion coefficient of the cured product of the epoxy resin composition and to suppress the volume shrinkage caused by the curing reaction of the epoxy resin composition.

[0030] The filler is not particularly limited as long as it is a substance contained in a general epoxy resin composition, and can be appropriately selected according to the purpose. Examples of fillers include inorganic particles. Examples of inorganic particles include silica and alumina. In addition, the filler can be a material having other functions such as coloring. As such a filler, for example, inorganic pigments such as white pigments can be cited. As inorganic pigments, for example, magnesium oxide (magnesia), titanium dioxide (titanium), zirconium dioxide (dialconia), boron nitride, aluminum nitride, titanium oxide (titanium oxide), magnesium oxide (magnesium oxide), zinc oxide, aluminum oxide (aluminum oxide), diamond, potassium titanate, magnesium sulfate, sepiolite, xonotlite (zonolite), aluminum borate, calcium carbonate, titanium oxide (titanium oxide), barium sulfate, zinc oxide, magnesium hydroxide, barium titanate, and zirconium oxide (dialconia) etc. can be cited. These may be used alone or in combination of two or more. Among these, silica fillers are preferred from the viewpoint of being able to increase the filling amount.

[0031] The filler may be a material that has been surface treated by a silane coupling agent or the like. By using a surface treated filler, the agglomeration of the filler can be suppressed and the dispersibility can be improved. In addition, the wettability with the resin component in the filler is improved, so the combination of the filler and the resin interface becomes stronger, and the bonding property of the filler and the resin component can be improved. Thus, the viscosity rise of the epoxy resin composition and the reduction of the injection speed can be suppressed, and the toughness of the cured product of the epoxy resin composition can be improved. The silane coupling agent is not particularly limited and can be appropriately selected according to the purpose. In consideration of adhesion to adherends such as substrates and chips, the silane coupling agent is preferably 3-methacryloxypropyltrimethoxysilane and N-phenyl-3-aminopropyltrimethoxysilane.

[0032] The shape of the filler is not particularly limited and can be appropriately selected depending on the purpose. Examples of the shape of the filler include spherical, irregular, and flaky shapes.

[0033] From the viewpoint of injectability, the volume average particle size of the filler (hereinafter referred to as average particle size) is preferably 0.5 μm to 2.0 μm, and more preferably 0.5 μm to 1.5 μm. The average particle size of the filler refers to a volume average particle size D50 (particle size at which 50% of the total particle size is accumulated from the small diameter side of the particle size distribution) value measured using a laser diffraction particle size distribution analyzer (LS13320, manufactured by Beckman Coreter). The average particle size was measured as follows. 5 mg of filler was dispersed in 50 mg of dispersant and dispersed for 10 minutes using an ultrasonic disperser to prepare a sample for measurement. The average particle size of the sample for measurement was measured under the conditions of a flow rate of 50 mL / second, a measurement time of 90 seconds, pure water as the solvent, and a solvent refractive index of 1.333.

[0034] Relative to the total amount of the epoxy resin composition, the content of the filler is 55% by mass or more and less than 77% by mass, preferably 60% by mass or more and 76% by mass or less, more preferably 70% by mass or more and 76% by mass or less, and further preferably 73% by mass or more and 76% by mass or less. If the value of the filler content is included in this range, the viscosity of the epoxy resin composition becomes a viscosity suitable for dispensing. Therefore, the injection operability of the bottom filling material in the installation process is improved, etc., so that the injectability is improved.

[0035] <Phenol-based curing agent> The phenolic curing agent is contained in order to promote the curing of the resin in the epoxy resin composition. The phenolic curing agent is not particularly limited and can be appropriately selected according to the purpose. As the phenolic curing agent, phenol, cresol, naphthol, alkylphenol, allylphenol, bisphenol, and terpene phenol can be mentioned. They can be used alone or in combination of two or more.

[0036] The content of the phenolic curing agent is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 0.5 to 2.0 mass %, more preferably 0.5 to 1.0 mass %.

[0037] <Other ingredients> As for other components, there are no particular restrictions as long as they are components commonly used for bottom filling materials, and they can be appropriately selected according to the purpose. As other components, for example, curing agents other than heterocyclic compounds having nitrogen atoms such as liquid acid anhydrides, liquid phenols and aromatic amines; colorants such as dyes, pigments and carbon black; silicone oils; surfactants; antioxidants; antimony oxides such as antimony trioxide, antimony tetroxide and antimony pentoxide, and existing well-known flame retardants such as brominated epoxy resins; ion capture agents; leveling agents; defoaming agents; reactive diluents, etc. These can be used alone or in combination of two or more.

[0038] The content of other components is not particularly limited and may be appropriately selected according to the purpose.

[0039] <Physical Properties of Epoxy Resin Composition> <<Viscosity>> From the viewpoint of injectability, the viscosity of the epoxy resin composition at 25° C. is preferably the following value. The viscosity of the epoxy resin composition when the epoxy resin composition just prepared is rotated at 50 rpm for 1 minute under the condition of 25° C. using a Brookfield viscometer is preferably 5 Pa·s to 45 Pa·s. The viscosity of the epoxy resin composition when the epoxy resin composition just prepared is rotated at 5 rpm for 1 minute under the condition of 25° C. using a Brookfield viscometer is preferably 2 Pa·s to 45 Pa·s. The thixotropic index (TI value: (viscosity at 5 rpm) / (viscosity at 50 rpm)) of the epoxy resin composition is preferably 0.3 to 1.2.

[0040] <<Chlorine Amount>> The chlorine content (total chlorine content) in the epoxy resin composition is preferably 1,300 ppm or less, more preferably 1,000 ppm or less. If the total chlorine content is greater than 1,300 ppm, the injectability and reliability may deteriorate, and the storage stability may also deteriorate.

[0041] <Application of epoxy resin composition> The epoxy resin composition of the embodiment can achieve both injectability and reliability, and thus can be suitably used as an underfill material. The epoxy resin composition can be suitably used in particular for mounting a semiconductor device having a fine pitch. For example, due to good injectability, even if the distance between the substrate and the semiconductor element is a fine gap of less than 15 μm and the distance between the bumps (the distance between the centers of the bumps) is a fine part of less than 150 μm, the epoxy resin composition can be injected for sealing. That is, the epoxy resin composition can be used for sealing semiconductor chips with a bump distance of less than 150 μm. In addition, due to good reliability, even when these fine parts are sealed, cracks can be suppressed between the substrate and the semiconductor element.

[0042] (Method for producing epoxy resin composition) The method for producing the epoxy resin composition of the embodiment can be appropriately selected depending on the purpose. As the production method, for example, there can be mentioned a method of mixing and stirring the above components.

[0043] When the epoxy resin is in a solid state, it is preferred that the epoxy resin be liquefied and fluidized by heating or the like before being mixed and stirred.

[0044] In addition, the components may be mixed simultaneously, or some components may be mixed first and then the remaining components may be mixed. In the case of epoxy resin, when it is difficult to uniformly disperse the filler, the epoxy resin and the filler may be mixed first and then the remaining components may be mixed.

[0045] The device used for mixing and stirring is not particularly limited and may be appropriately selected depending on the purpose. Examples of the device include a roll mill and the like.

[0046] (Semiconductor Device) A semiconductor device according to an embodiment includes a support, a cured product of the epoxy resin composition, and a semiconductor element. Examples of the semiconductor device include a semiconductor device sealed with the epoxy resin composition, for example, a semiconductor device in which a semiconductor element and a support are sealed with a cured product of the epoxy resin composition.

[0047] <Support> The support is not particularly limited as long as it can fix the semiconductor element, and can be appropriately selected according to the purpose. Examples of the support include substrates.

[0048] <<Substrate>> The substrate is not particularly limited and may be appropriately selected depending on the purpose. Examples of the substrate include a lead frame, a wired tape carrier, a wiring board, glass, and a silicon wafer. The size, shape, and material of the substrate are not particularly limited as long as they are the size, shape, and material of commonly used substrates, and can be appropriately selected according to the purpose.

[0049] <Semiconductor Components> The semiconductor element is not particularly limited and can be appropriately selected according to the purpose. Examples of semiconductor elements include active elements such as semiconductor chips, transistors, diodes, and thyristors; and passive elements such as capacitors, resistors, resistor arrays, coils, and switches. The size, shape, and material of the semiconductor element are not particularly limited as long as they are the size, shape, and material of a commonly used semiconductor element, and can be appropriately selected depending on the purpose.

[0050] The cured product of the epoxy resin composition is provided between the support and the semiconductor element. The thickness of the cured product of the epoxy resin composition is not particularly limited and may be appropriately selected depending on the intended purpose. Examples of the range of the thickness include 10 μm or more and 800 μm or less. The shape of the cured product of the epoxy resin composition is not particularly limited and may be appropriately selected depending on the intended purpose.

[0051] (Method for manufacturing semiconductor device) The method for manufacturing a semiconductor device according to the embodiment includes a step of filling the epoxy resin composition and a step of curing the epoxy resin composition, and further includes other steps as necessary.

[0052] <Step of Filling Epoxy Resin Composition> The step of filling the epoxy resin composition is a step of filling the epoxy resin composition into the gap between the support and the semiconductor element disposed on the support. In this step, mold underfill for sealing the entire semiconductor element at once can be performed. As the support, the above-mentioned supports can be used. The method of filling the epoxy resin composition is not particularly limited and can be appropriately selected depending on the purpose. Examples of the method include a dispensing method, an injection molding method, and a printing method. The amount of the epoxy resin composition to be filled is not particularly limited and can be appropriately selected according to the purpose. For example, the amount can be an amount that completely fills the gap between the semiconductor element and the support and further covers the side of the semiconductor element with the epoxy resin composition (an amount that forms a rounded corner).

[0053] <Step of Curing the Epoxy Resin Composition> The step of curing the epoxy resin composition is a step of curing the epoxy resin composition between the support and the semiconductor element. The method for curing the epoxy resin composition is not particularly limited and may be appropriately selected depending on the intended purpose. Examples of the method include a method of heating the epoxy resin composition. The heating temperature is not particularly limited and may be appropriately selected depending on the purpose, but is preferably 120°C to 200°C, more preferably 130°C to 180°C, and further preferably 140°C to 170°C from the viewpoint of reliability. The heating time is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 15 minutes to 3 hours, more preferably 30 minutes to 2 hours, from the viewpoint of operability. Example

[0054] (Example 1 to Example 14, Comparative Example 1 to Comparative Example 5) The mixtures were mixed in the ratios shown in Tables 1 to 4 using a three-roll mill and further homogenized to obtain epoxy resin compositions.

[0055] [Table 1]

[0056] [Table 2]

[0057] [Table 3]

[0058] [Table 4]

[0059] The polyalkylene glycol type epoxy resins used in Examples and Comparative Examples are as follows. Polytetramethylene glycol type epoxy resin 1 (YX-7400N, manufactured by Mitsubishi Chemical Co., Ltd., chlorine content: 500 ppm) · Polytetramethylene glycol type epoxy resin 2 (Epogose PT, manufactured by Yokkaichi Synthetic Co., Ltd., chlorine content: 18,000 ppm)

[0060] The epoxy resins (epoxy resins other than polyalkylene glycol type epoxy resins) used in Examples and Comparative Examples are as follows. Epoxy resin 1 (RE410S, manufactured by Nippon Kagyaku Co., Ltd., bisphenol A type epoxy resin, chlorine content: 900 ppm) Epoxy resin 2 (YDF-8170, manufactured by Nippon Steel Chemical & Material Co., Ltd., bisphenol F type epoxy resin, chlorine content: 900 ppm) Epoxy resin 3 (jER 630, manufactured by Mitsubishi Chemical Co., Ltd., aromatic amine type trifunctional epoxy resin, chlorine content: 5,000 ppm) Epoxy resin 4 (EP-3980S, manufactured by ADEKA Co., Ltd., aromatic amine type bifunctional epoxy resin, chlorine content: 700 ppm) Epoxy resin 5 (ZX-1658GS, manufactured by Nippon Steel Chemical & Material Co., Ltd., cycloaliphatic epoxy resin, chlorine content: 600 ppm)

[0061] The nitrogen atom-containing heterocyclic compounds used in Examples and Comparative Examples are as follows. Imidazole derivative (Cuazol 2P4MZ, manufactured by Shikoku Chemical Industries, Ltd., 2-phenyl-4-methyl-1H-imidazole) · Triazine derivative (2MZA, manufactured by Shikoku Chemical Industry Co., Ltd., 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine)

[0062] The fillers used in Examples and Comparative Examples are as follows. Filler 1 (SE605H-SMG, manufactured by Admatex Co., Ltd., silica surface-treated with 3-methacryloxypropyltrimethoxysilane, average particle size: 2.0 μm) Filler 2 (15SM-E13, manufactured by Adomatex Co., Ltd., silica surface-treated with 3-methacryloxypropyltrimethoxysilane, average particle size: 1.5 μm) Filler 3 (SE2200-SME, manufactured by Advantex Co., Ltd., silica surface-treated with 3-methacryloxypropyltrimethoxysilane, average particle size: 0.6 μm) Filler 4 (SE2200-SEE, manufactured by Adomatex Co., Ltd., silica surface-treated with 3-glycidoxypropyltrimethoxysilane, average particle size: 0.6 μm) Filler 5 (SE1050-SMO, manufactured by Advantex Co., Ltd., silica surface-treated with 3-methacryloxypropyltrimethoxysilane, average particle size: 0.3 μm) Filler 6 (40SM-E2, manufactured by ADROMATEX CO., LTD., silica surface-treated with 3-methacryloxypropyltrimethoxysilane, average particle size: 4 μm)

[0063] Other components used in Examples and Comparative Examples are as follows. 3-Glycidoxypropyltrimethoxysilane (KBM403, manufactured by Shin-Etsu Chemical Co., Ltd.) ·3-Isocyanatepropyltriethoxysilane (KBE9007N, manufactured by Shin-Etsu Chemical Co., Ltd.) ·Carbon black (Bullarco 4, manufactured by Ariel Technologies Co., Ltd.) ·Modified silicone (SF8421, manufactured by Higashikata Chemical Co., Ltd.) Phenolic curing agent (MEH8000, manufactured by UBE Co., Ltd., allylphenol) ·Amine curing agent (Etacur 100, manufactured by Albemarle Japan Co., Ltd., diethyltoluenediamine)

[0064] The viscosity of the epoxy resin compositions of the examples and comparative examples was measured as follows. In addition, injectability, void generation rate, reliability, and linear expansion coefficient were evaluated. The evaluation results are collectively recorded in Tables 1 to 4.

[0065] <Viscosity> The viscosity of each epoxy resin composition immediately after preparation (initial viscosity, unit: Pa·s) was measured using a Brookfield viscometer when the epoxy resin composition was rotated at 50 rpm and 5 rpm for 1 minute at 25° C. The thixotropic index (TI: (viscosity at 5 rpm) / (viscosity at 50 rpm)) was determined from the obtained values ​​of the viscosities at 50 rpm and 5 rpm.

[0066] <Injectability> Two gap bands (made of stainless steel (SUS), thickness: 15μm) are arranged on a glass slide at an interval of 1cm. Cover another glass slide from above, and fix the two glass slides with a clip. A test piece was thus prepared, which is a test piece containing two glass slides with a gap of 1cm in width and 15μm in height. The test piece was placed on a hot plate set at 90°C, and each epoxy resin composition was applied to one end of the gap in the glass slide. Furthermore, for each epoxy resin composition, the time (min) for the injection distance to reach 20mm was measured. This step was carried out twice, and the average value of the measured values ​​was used as the evaluation result of the injectability.

[0067] <Void Generation Rate> A silicon chip (WALTS-TEG FC150JY (PI), manufactured by Walts) was mounted on a substrate (WALTS-KITFC150-0103JY2×2 (SAC), manufactured by Walts). Each epoxy resin composition was applied to the substrate and heat-cured at 180°C for 60 minutes to obtain a test piece. Five test pieces were prepared. Afterwards, each epoxy resin composition was observed by an ultrasonic flaw detector (scanning ultrasonic microscope, Fine SAT FS300 III) to determine the number of test pieces with voids (bubbles). In addition, the occurrence rate of voids is preferably 1 / 5 or less (1 or less in 5 test pieces).

[0068] <Reliability> The test pieces used in the above void generation rate were subjected to a preconditioning test under JEDEC Level 3 (30°C, 60% RH, 168 hours). Afterwards, the test pieces were subjected to a 1000-cycle thermal cycle (-55°C to 125°C) under Condition B. Afterwards, the epoxy resin compositions at the fillet of the test piece were observed under a microscope (magnification: 10 times) to determine the number of test pieces with fillet cracks. In addition, the occurrence rate of fillet cracks is preferably 2 / 5 (2 or less in 5 test pieces).

[0069] <Linear expansion coefficient> Each epoxy resin composition was injected into a silicone rubber mold and heat-cured at 180°C for 60 minutes to obtain a test piece (8 mm in diameter and 20 mm in height). The test piece was annealed by TMA (thermomechanical analyzer, TMA4000SA, manufactured by BRUKER AXS) to achieve a temperature increase of 20°C per minute from room temperature to 220°C. Then, the linear expansion coefficient was determined by a compression load method under the condition of a temperature increase of 5°C per minute from -30°C to 230°C. As the measurement conditions of the linear expansion coefficient, CTE1 was set to a range of 10°C to 30°C, and CTE2 was set to a range of 180°C to 200°C, and the measurement was performed.

[0070] As shown in Tables 1 to 3, it is clear that the injectability and reliability of the epoxy resin composition of the embodiment are evaluated as good. In contrast, the evaluation result of the injectability of the epoxy resin composition of Comparative Example 1 with a filler content of 78% by mass is 25 minutes, and the injectability is poor. In addition, the evaluation result of the reliability of the epoxy resin composition of Comparative Example 2 with a filler content of 50.0% by mass is 4 / 5, and the reliability is poor. Furthermore, the evaluation results of the reliability of Comparative Example 3 and Comparative Example 4, which do not contain polyalkylene glycol type epoxy resins, are both 5 / 5, and the reliability is poor. The evaluation of the linear expansion coefficient of Comparative Example 5, which does not contain a nitrogen-containing heterocyclic compound and uses an amine-based curing agent, is poor and the reliability is poor. It is clear from the above content that the following epoxy resin composition is an epoxy resin composition that takes into account both injectability and reliability: an epoxy resin composition, the epoxy resin composition contains a polyalkylene glycol type epoxy resin, a heterocyclic compound containing a nitrogen atom, and a filler, wherein the content of the filler is greater than 55% by mass and less than 77% by mass relative to the total amount of the epoxy resin composition.

[0071] The embodiments and examples of the present disclosure are described. These are presented as examples and are not intended to limit the technical scope of the present disclosure. The embodiments can be implemented in various other ways, and various omissions, substitutions and changes can be made to the embodiments without departing from the gist of the present disclosure. The embodiments and their variations are included in the technical scope and gist of the present disclosure, and similarly, are also included in the technical ideas and their equivalents recorded in the claims.

Claims

1. An epoxy resin composition, comprising an epoxy resin, a nitrogen-containing heterocyclic compound, and a filler, wherein: The epoxy resin contains at least a polyalkylene glycol type epoxy resin, The content of the filler is 55 mass % or more and less than 77 mass % based on the total amount of the epoxy resin composition.

2. The epoxy resin composition according to claim 1, wherein The average particle size of the filler is 0.5 μm to 2.0 μm.

3. The epoxy resin composition according to claim 1 or 2, wherein The content of the polyalkylene glycol epoxy resin is 10% by mass to 30% by mass based on the epoxy resin.

4. The epoxy resin composition according to any one of claims 1 to 3, wherein The epoxy resin composition has a chlorine content of 1,300 ppm or less.

5. The epoxy resin composition according to any one of claims 1 to 4, wherein The polyalkylene glycol type epoxy resin is a polytetramethylene glycol type epoxy resin.

6. The epoxy resin composition according to any one of claims 1 to 5, wherein The epoxy resin composition further contains at least one selected from the group consisting of a glycidylamine epoxy resin, a bisphenol epoxy resin, and an aliphatic epoxy resin.

7. The epoxy resin composition according to any one of claims 1 to 6, wherein The nitrogen-containing heterocyclic compound is at least one selected from 2-phenyl-4-methylimidazole and 2,4-diamino-6-[2'-methylimidazolyl-(1)']-ethyl-s-triazine.

8. The epoxy resin composition according to any one of claims 1 to 7, wherein The epoxy resin composition further contains a phenolic curing agent.

9. The epoxy resin composition according to any one of claims 1 to 8, wherein The epoxy resin composition is used for sealing a semiconductor chip with a bump pitch of less than 150 μm.

10. A semiconductor device, wherein: The semiconductor device is a semiconductor device sealed with the epoxy resin composition according to any one of claims 1 to 9.

11. A method for manufacturing a semiconductor device, wherein: The manufacturing method has the following features: A step of filling the epoxy resin composition according to claim 8 into a gap between a support and a semiconductor element disposed on the support, and A step of curing the epoxy resin composition.

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