Semiconductor chip package manufacturing method

Abstract

To provide a method of manufacturing a semiconductor chip package that is capable of providing a semiconductor chip package in which the generation of voids is suppressed.SOLUTION: A method for manufacturing a semiconductor chip package includes the steps of (I) laminating a resin composition layer of a resin sheet, which includes a support and the resin composition layer provided on the support, on a semiconductor chip package having at least one semiconductor chip mounted on a circuit board, and performing mold underfill, and (II) thermally curing the resin composition layer, in this order, wherein the resin composition layer has a loss tangent of 0.05 or more and 1.3 or less at a temperature at which the mold underfill is performed.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing a semiconductor chip package. [Background technology]

[0002] Demand for semiconductor chip packages, which contain semiconductor chips bonded onto circuit boards, is increasing with the spread of smartphones, etc. To protect the bonding and wiring between the circuit board and semiconductor chip from the external environment, one method of semiconductor chip packaging involves underfilling the gap between the circuit board and semiconductor chip with an encapsulant, and then overmolding the semiconductor chip package with another encapsulant.

[0003] This method has the problem of requiring many steps and being time-consuming. Furthermore, using different encapsulating materials can cause stress at the resin interface, resulting in reduced reliability. For this reason, a mold underfill method has been proposed, in which overmolding and underfilling are performed simultaneously using a mold underfill encapsulating material, as in Patent Document 1. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6894077 Summary of the Invention [Problem to be solved by the invention]

[0005] In recent years, the gap between a circuit board and a semiconductor chip and the gap between electrodes have become increasingly narrower in order to increase the density of electronic components. The inventors have confirmed that conventional mold underfill encapsulating materials do not penetrate sufficiently into the gaps and between electrodes. Insufficient penetration into the gaps and between electrodes results in poor filling of the mold underfill encapsulating material into the gaps and between electrodes, resulting in the formation of voids. The formation of voids can lead to swelling during thermal curing of the encapsulating material and reduced reliability.

[0006] The present invention has been made in view of the above-mentioned problems, and has as its object to provide a method for manufacturing a semiconductor chip package that can provide a semiconductor chip package in which the occurrence of voids is suppressed. [Means for solving the problem]

[0007] As a result of extensive research, the present inventors have found that the above problems can be solved by a method for manufacturing a semiconductor chip package having the following configuration, and have thus completed the present invention.

[0008] That is, the present invention includes the following. [1] (I) A step of laminating a resin composition layer of a resin sheet having a support and a resin composition layer provided on the support on a semiconductor chip package in which at least one semiconductor chip is mounted on a circuit board, and performing mold underfill; (II) a step of thermally curing the resin composition layer; 1. A method for manufacturing a semiconductor chip package, comprising, in this order: A method for producing a semiconductor chip package, wherein the resin composition layer has a loss tangent of 0.05 or more and 1.3 or less at a temperature for performing mold underfilling. [2] The method for producing a semiconductor chip package according to [1], wherein in step (I), the temperature at which the mold underfill is performed is 70°C or higher and 180°C or lower. [3] The method for producing a semiconductor chip package according to [1] or [2], wherein in step (II), the resin composition layer is subjected to a heat treatment in which it is maintained at a temperature T1, and then subjected to a heat treatment in which it is maintained at a temperature T2 higher than the temperature T1. [4] The method for producing a semiconductor chip package according to any one of [1] to [3], wherein the resin composition layer contains (A) an inorganic filler. [5] The method for producing a semiconductor chip package according to [4], wherein the content of (A) inorganic filler is 65% by mass or more when the nonvolatile components of the resin composition layer are 100% by mass. [6] The method for producing a semiconductor chip package according to any one of [1] to [5], wherein the melt viscosity of the resin composition layer is 1,000 poise or more and 10,000 poise or less. [7] The method for manufacturing a semiconductor chip package according to any one of [1] to [6], wherein the gap between the circuit board and the semiconductor chip is 60 μm or less. [8] The method for manufacturing a semiconductor chip package according to any one of [3] to [7], wherein the temperature T2 is 150° C. or higher. [9] The method for manufacturing a semiconductor chip package according to any one of [3] to [8], wherein the difference T2-T1 between the temperature T1 and the temperature T2 is 20° C. or more.

[10] The method for manufacturing a semiconductor chip package according to any one of [3] to [9], wherein the temperature T1 is 50° C. or higher. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a method for manufacturing a semiconductor chip package that can provide a semiconductor chip package in which the occurrence of voids is suppressed. DETAILED DESCRIPTION OF THE INVENTION

[0010] The present invention will be described in detail below with reference to preferred embodiments thereof. However, the present invention is not limited to the following embodiments and examples, and can be implemented with any modifications within the scope of the claims of the present invention and their equivalents.

[0011] Before describing the method for manufacturing a semiconductor chip package of the present invention in detail, the resin sheet used in the manufacturing method will be described.

[0012] [Resin sheet] The resin sheet comprises a support and a resin composition layer provided on the support, and the resin composition layer has a loss tangent (tan δ) of 0.05 or more and 1.3 or less at a temperature where mold underfilling is performed.

[0013] <Support> The resin sheet has a support, which may be, for example, a film made of a plastic material, a metal foil, or a release paper, with a film made of a plastic material or a metal foil being preferred.

[0014] When a film made of a plastic material is used as the support, examples of the plastic material include polyesters such as polyethylene terephthalate (hereinafter sometimes abbreviated as "PET") and polyethylene naphthalate (hereinafter sometimes abbreviated as "PEN"), polycarbonate (hereinafter sometimes abbreviated as "PC"), acrylics such as polymethyl methacrylate (PMMA), cyclic polyolefins, triacetyl cellulose (TAC), polyether sulfide (PES), polyether ketone, polyimide, etc. Among these, polyethylene terephthalate and polyethylene naphthalate are preferred, with inexpensive polyethylene terephthalate being particularly preferred.

[0015] When a metal foil is used as the support, examples of the metal foil include copper foil and aluminum foil, with copper foil being preferred. The copper foil may be a foil made of a single metal, copper, or an alloy of copper and another metal (e.g., tin, chromium, silver, magnesium, nickel, zirconium, silicon, titanium, etc.).

[0016] The surface of the support that is to be bonded to the resin composition layer may be subjected to a matte treatment, a corona treatment, or an antistatic treatment.

[0017] The support may also be a support with a release layer, which has a release layer on the surface that bonds to the resin composition layer. Examples of the release agent used in the release layer of the support with a release layer include one or more release agents selected from the group consisting of alkyd resins, polyolefin resins, urethane resins, and silicone resins. Commercially available products may also be used as the support with a release layer, including, for example, "SK-1," "AL-5," and "AL-7" manufactured by Lintec Corporation, "Lumirror T60" manufactured by Toray Industries, Inc., "Purex" manufactured by Teijin Limited, and "Uni-Peel" manufactured by Unitika Limited, which are PET films having a release layer primarily composed of an alkyd resin-based release agent.

[0018] The thickness of the support is not particularly limited, but is preferably 1 μm or more, more preferably 5 μm or more, even more preferably 10 μm or more, and is preferably 75 μm or less, more preferably 60 μm or less, even more preferably 50 μm or less. When a support with a release layer is used, it is preferable that the thickness of the entire support with a release layer is within the above range.

[0019] <Resin composition layer> The resin sheet includes a resin composition layer made of a resin composition. The resin composition layer is a material that simultaneously fills the gap (gap) between the circuit board and the semiconductor chip and seals the semiconductor chip. The resin composition layer is bonded to the support to form the resin sheet. The resin composition layer may be one layer or two or more layers, but from the viewpoint of significantly obtaining the effects of the present invention, it is preferable that the resin composition layer be one layer.

[0020] The resin composition layer has a loss tangent (tanδ) of 0.05 or more and 1.3 or less at the temperature where mold underfilling is performed. The inventors have discovered that by adjusting the loss tangent at the temperature where mold underfilling is performed within this range, external pressure applied during mold underfilling is efficiently applied to the resin composition layer, making the resin composition layer more likely to flow. This makes it easier for the resin composition layer to penetrate and fill even narrow gaps between the circuit board and semiconductor chip or between electrodes. As a result, the generation of voids is suppressed.

[0021] The loss tangent (tan δ) is the value obtained by dividing the loss modulus by the storage modulus (loss modulus / storage modulus), and the temperature at which mold underfilling is performed is the temperature at which mold underfilling is performed in step (I) described below. Specifically, when mold underfilling is performed by laminating a resin composition layer so as to bond it to a semiconductor chip package, this refers to the thermocompression bonding temperature during lamination, and when mold underfilling is performed by hot pressing, this refers to the temperature of the mold during hot pressing. Hereinafter, the temperature at which mold underfilling is performed may be simply referred to as the "molding temperature."

[0022] From the viewpoint of filling the gap between the circuit board and the semiconductor chip and the gap between the electrodes with the resin composition layer, the loss tangent at the molding temperature is 0.05 or more, preferably 0.1 or more, more preferably 0.15 or more, 0.2 or more, 0.25 or more, 0.3 or more, 0.35 or more, 0.4 or more, or 0.45 or more. The upper limit is 1.3 or less, preferably 1.28 or less, more preferably 1.25 or less, and even more preferably 1.23 or less. The loss tangent can be measured by the method described in the examples below.

[0023] The melt viscosity of the resin composition layer is preferably 1,000 poise or more, more preferably 2,000 poise or more, even more preferably 3,000 poise or more or 4,000 poise or more, and preferably 10,000 poise or less, more preferably 9,000 poise or less, even more preferably 8,000 poise or less, 7,000 poise or less, or 6,000 poise or less. By adjusting the melt viscosity of the resin composition layer to be within this range, it becomes possible to fill the gap between the circuit board and the semiconductor chip with the resin composition layer. The melt viscosity is the melt viscosity at the molding temperature and can be measured by the method described in the examples below.

[0024] The components contained in the resin composition layer may be any components that have a loss tangent within the above range and whose cured product has sufficient hardness and insulating properties. Examples of components contained in such a resin composition layer include (A) an inorganic filler. The resin composition layer may further contain, as necessary, (B) an epoxy resin, (C) a curing agent, (D) an elastomer, (E) a thermoplastic resin, (F) a curing accelerator, (G) a radically polymerizable resin, (H) a radical polymerization initiator, (I) a flame retardant, (J) other additives, and (K) a solvent.

[0025] -(A) Inorganic filler- The resin composition layer contains an inorganic filler (A) as the component (A). By including the inorganic filler (A) in the resin composition layer, a cured product with a low dielectric loss tangent can be obtained, and the loss tangent can be set to 0.05 or more and 1.3 or less. The inorganic filler (A) is usually included in the resin composition layer in the form of particles. The component (A) may be used alone or in combination of two or more.

[0026] (A) Inorganic fillers are inorganic compounds. Examples of (A) inorganic filler materials include silica, alumina, glass, cordierite, silicon oxide, barium sulfate, barium carbonate, talc, clay, mica powder, zinc oxide, hydrotalcite, boehmite, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, aluminum nitride, manganese nitride, aluminum borate, strontium carbonate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, zirconium oxide, barium titanate, barium titanate zirconate, barium zirconate, calcium zirconate, zirconium phosphate, and zirconium tungstate phosphate. Among these, silica is particularly preferred. Examples of silica include amorphous silica, fused silica, crystalline silica, synthetic silica, and hollow silica. Spherical silica is preferred.

[0027] (A) Examples of commercially available inorganic fillers include "SP60-05" and "SP507-05" manufactured by Nippon Steel Chemical & Material Co., Ltd.; "YC100C," "YA050C," "YA050C-MJE," "YA010C," "SC2500SQ," "SO-C4," "SO-C2," and "SO-C1" manufactured by Admatechs Co., Ltd.; "UFP-30," "DAW-03," and "FB-105FD" manufactured by Denka Company, Limited; "Silfil NSS-3N," "Silfil NSS-4N," and "Silfil NSS-5N" manufactured by Tokuyama Corporation; "CellSpheres" and "MGH-005" manufactured by Taiheiyo Cement Corporation; and "Sferique" and "BA-1" manufactured by JGC Catalysts and Chemicals Co., Ltd.

[0028] The average particle size of the (A) inorganic filler is preferably small so that the resin composition layer can easily penetrate and fill gaps and spaces between electrodes. Specifically, it is preferably 0.01 μm or more, more preferably 0.1 μm or more, and even more preferably 0.3 μm or more, and is preferably 10 μm or less, more preferably 5 μm or less, and even more preferably 3 μm or less.

[0029] (A) The average particle size of an inorganic filler can be measured by a laser diffraction / scattering method based on Mie scattering theory. Specifically, a volumetric particle size distribution of the inorganic filler is created using a laser diffraction / scattering particle size distribution analyzer, and the median diameter is used as the average particle size. A measurement sample can be prepared by weighing 100 mg of inorganic filler and 10 g of methyl ethyl ketone into a vial and dispersing the mixture ultrasonically for 10 minutes. The volumetric particle size distribution of the inorganic filler is measured using a laser diffraction particle size distribution analyzer with blue and red light source wavelengths using a flow cell system, and the average particle size can be calculated as the median diameter from the particle size distribution obtained. Examples of laser diffraction particle size distribution analyzers include the LA-960 manufactured by Horiba, Ltd.

[0030] The BET specific surface area of ​​the (A) inorganic filler is preferably 0.1 m 2 / g or more, more preferably 0.5m 2 / g or more, more preferably 1m2 / g or more, preferably 100m 2 / g or less, more preferably 70m 2 / g or less, more preferably 40m 2 / g or less.

[0031] (A) The specific surface area of ​​the inorganic filler can be measured according to the BET method by adsorbing nitrogen gas onto the sample surface using a specific surface area measuring device (Macsorb HM-1210 manufactured by Mountech Co., Ltd.) and calculating the specific surface area using the BET multipoint method.

[0032] The (A) inorganic filler is preferably treated with a surface treatment agent from the viewpoint of improving moisture resistance and dispersibility. Examples of the surface treatment agent include a fluorine-containing silane coupling agent, an aminosilane coupling agent, an epoxysilane coupling agent, a mercaptosilane coupling agent, a silane coupling agent, an alkoxysilane, an organosilazane compound, and a titanate coupling agent. One type of surface treatment agent may be used alone, or two or more types may be used in any combination.

[0033] Examples of commercially available surface treatment agents include Shin-Etsu Chemical Co., Ltd.'s "KBM403" (3-glycidoxypropyltrimethoxysilane), Shin-Etsu Chemical Co., Ltd.'s "KBM803" (3-mercaptopropyltrimethoxysilane), Shin-Etsu Chemical Co., Ltd.'s "KBE903" (3-aminopropyltriethoxysilane), Shin-Etsu Chemical Co., Ltd.'s "KBM573" (N-phenyl-3-aminopropyltrimethoxysilane), Shin-Etsu Chemical Co., Ltd.'s "SZ-31" (hexamethyldisilazane), Shin-Etsu Chemical Co., Ltd.'s "KBM103" (phenyltrimethoxysilane), Shin-Etsu Chemical Co., Ltd.'s "KBM-4803" (long-chain epoxy-type silane coupling agent), and Shin-Etsu Chemical Co., Ltd.'s "KBM-7103" (3,3,3-trifluoropropyltrimethoxysilane).

[0034] The degree of surface treatment with the surface treatment agent preferably falls within a specific range from the viewpoint of improving the dispersibility of the inorganic filler. Specifically, 100% by mass of the inorganic filler is preferably surface-treated with 0.2% to 5% by mass of the surface treatment agent, more preferably with 0.2% to 3% by mass of the surface treatment agent, and even more preferably with 0.3% to 2% by mass of the surface treatment agent.

[0035] The degree of surface treatment with the surface treatment agent can be evaluated by the amount of carbon per unit surface area of ​​the inorganic filler. From the viewpoint of improving the dispersibility of the inorganic filler, the amount of carbon per unit surface area of ​​the inorganic filler is set to 0.02 mg / m 2 More than 0.1 mg / m is preferable. 2 More preferably, 0.2 mg / m or more 2 On the other hand, from the viewpoint of preventing an increase in the melt viscosity of the resin composition layer, it is more preferable that the amount of the resin composition layer is 1.0 mg / m 2 Less than 0.8 mg / m is preferred 2 Less than 0.5 mg / m is more preferable. 2 The following is even more preferred:

[0036] (A) The amount of carbon per unit surface area of ​​an inorganic filler can be measured after the surface-treated inorganic filler is washed with a solvent (e.g., methyl ethyl ketone (MEK)). Specifically, a sufficient amount of MEK as a solvent is added to the inorganic filler that has been surface-treated with a surface treatment agent, and ultrasonic cleaning is performed at 25°C for 5 minutes. After removing the supernatant and drying the solid content, the amount of carbon per unit surface area of ​​the inorganic filler can be measured using a carbon analyzer. An "EMIA-320V" manufactured by Horiba, Ltd., or the like can be used as the carbon analyzer.

[0037] The degree of surface treatment with a surface treatment agent can be evaluated by the amount of carbon per unit mass of the inorganic filler. The amount of carbon per unit mass of the inorganic filler is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, and even more preferably 0.1% by mass or more, and is preferably 1.0% by mass or less, more preferably 0.8% by mass or less, and even more preferably 0.5% by mass or less. The amount of carbon per unit mass of (A) inorganic filler can be measured using a carbon analyzer, just like the amount of carbon per unit surface area of ​​(A) inorganic filler.

[0038] The content of the (A) inorganic filler is preferably 65% ​​by mass or more, more preferably 70% by mass or more, even more preferably 75% by mass or more, or 80% by mass or more, and is preferably 95% by mass or less, more preferably 90% by mass or less, even more preferably 85% by mass or less, based on 100% by mass of the nonvolatile components in the resin composition layer. By adjusting the content of the (A) inorganic filler within this range, it becomes easier to adjust the loss tangent within the above range.

[0039] In the present invention, unless otherwise specified, the content of each component in the resin composition layer is a value when the non-volatile components in the resin composition layer are 100% by mass, and the non-volatile components mean all non-volatile components in the resin composition layer excluding the solvent.

[0040] -(B) Epoxy resin- The resin composition layer may contain a (B) epoxy resin as the (B) component. By containing the (B) epoxy resin, a cured product exhibiting good mechanical strength and insulation reliability can be obtained. The (B) epoxy resin may be used alone or in combination of two or more types.

[0041] (B) Epoxy resins include, for example, bixylenol type epoxy resins, bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol S type epoxy resins, bisphenol AF type epoxy resins, dicyclopentadiene type epoxy resins, trisphenol type epoxy resins, naphthol novolac type epoxy resins, phenol novolac type epoxy resins, tert-butyl-catechol type epoxy resins, naphthalene type epoxy resins, naphthol type epoxy resins, anthracene type epoxy resins, glycidylamine type epoxy resins, and glycidyl ester type Examples of the epoxy resin include epoxy resins, glycidyl cyclohexane-type epoxy resins, alkyl diglycidyl ether-type epoxy resins, cresol novolac-type epoxy resins, biphenyl-type epoxy resins, linear aliphatic epoxy resins, epoxy resins having a butadiene structure, alicyclic epoxy resins, heterocyclic epoxy resins, spiro ring-containing epoxy resins, cyclohexane-type epoxy resins, cyclohexane dimethanol-type epoxy resins, naphthylene ether-type epoxy resins, trimethylol-type epoxy resins, tetraphenylethane-type epoxy resins, and phenolphthalimidine-type epoxy resins. One type of epoxy resin may be used alone, or two or more types may be used in combination.

[0042] The resin composition layer preferably contains, as component (B), an epoxy resin having two or more epoxy groups in one molecule. From the viewpoint of significantly achieving the desired effects of the present invention, the proportion of the epoxy resin having two or more epoxy groups in one molecule relative to 100% by mass of the epoxy resin (A) is preferably 50% by mass or more, more preferably 60% by mass or more, and particularly preferably 70% by mass or more.

[0043] Epoxy resins include epoxy resins that are liquid at a temperature of 20°C (hereinafter sometimes referred to as "liquid epoxy resins") and epoxy resins that are solid at a temperature of 20°C (hereinafter sometimes referred to as "solid epoxy resins"). The resin composition layer may contain, as component (B), only a liquid epoxy resin, only a solid epoxy resin, or a combination of a liquid epoxy resin and a solid epoxy resin.

[0044] The liquid epoxy resin is preferably a liquid epoxy resin having two or more epoxy groups in one molecule.

[0045] Preferred liquid epoxy resins include bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol AF type epoxy resins, naphthalene type epoxy resins, glycidyl ester type epoxy resins, glycidyl amine type epoxy resins, phenol novolac type epoxy resins, alicyclic epoxy resins having an ester skeleton, cyclohexane type epoxy resins, cyclohexane dimethanol type epoxy resins, glycidyl amine type epoxy resins, epoxy resins having a butadiene structure, glycidyl cyclohexane type epoxy resins, phenolphthalimidine type epoxy resins, and alkyl diglycidyl ether type epoxy resins, and bisphenol A type epoxy resins, bisphenol F type epoxy resins, and epoxy resins having a butadiene structure are more preferred.

[0046] Specific examples of liquid epoxy resins include "HP4032", "HP4032D", and "HP4032SS" (naphthalene type epoxy resins) manufactured by DIC Corporation; "828US", "jER828EL", "825", and "Epikote 828EL" (bisphenol A type epoxy resins) manufactured by Mitsubishi Chemical Corporation; "jER807" and "1750" (bisphenol F type epoxy resins) manufactured by Mitsubishi Chemical Corporation; "jER152" (phenol novolac type epoxy resin) manufactured by Mitsubishi Chemical Corporation; "630" and "630LSD" (glycidylamine type epoxy resins) manufactured by Mitsubishi Chemical Corporation; and "ZX1059" (bisphenol A type epoxy resin) manufactured by Nippon Steel Chemical & Material Co., Ltd. Examples of epoxy resins include "EX-721" (glycidyl ester epoxy resin) manufactured by Nagase ChemteX Corporation, "Celloxide 2021P" (alicyclic epoxy resin having an ester skeleton) manufactured by Daicel Corporation, "PB-3600" (epoxy resin having a butadiene structure) manufactured by Daicel Corporation, "ZX1658" and "ZX1658GS" (liquid 1,4-glycidylcyclohexane epoxy resin) manufactured by Nippon Steel Chemical & Material Co., Ltd., "YED216D" (alkyl diglycidyl ether epoxy resin) manufactured by Mitsubishi Chemical Corporation, and "YD-8125G" (bisphenol A epoxy resin) manufactured by Nippon Steel & Sumitomo Metal Chemical Co., Ltd. These may be used alone or in combination of two or more.

[0047] As the solid epoxy resin, a solid epoxy resin having two or more epoxy groups in one molecule is preferred, a solid epoxy resin having three or more epoxy groups in one molecule is more preferred, and an aromatic solid epoxy resin having three or more epoxy groups in one molecule is even more preferred.

[0048] Preferred solid epoxy resins are bixylenol-type epoxy resins, naphthalene-type epoxy resins, naphthalene-type tetrafunctional epoxy resins, cresol novolac-type epoxy resins, dicyclopentadiene-type epoxy resins, trisphenol-type epoxy resins, naphthol-type epoxy resins, biphenyl-type epoxy resins, naphthylene ether-type epoxy resins, anthracene-type epoxy resins, bisphenol A-type epoxy resins, bisphenol AF-type epoxy resins, and tetraphenylethane-type epoxy resins, with bixylenol-type epoxy resins, naphthylene ether-type epoxy resins, biphenyl-type epoxy resins, naphthalene-type epoxy resins, and naphthol-type epoxy resins being more preferred.

[0049] Specific examples of solid epoxy resins include "HP4032H" (naphthalene type epoxy resin), "HP-4700", "HP-4710" (naphthalene type tetrafunctional epoxy resin), "N-690" (cresol novolac type epoxy resin), "N-695" (cresol novolac type epoxy resin), "HP-7200", "HP-7200HH", "HP-7200H" (dicyclopentadiene type epoxy resin), "EXA-7311", "EXA-7311-G3", "EXA-7311-G4", "EXA-7311-G4S", "HP6000", "HP6000L" (naphthylene ether type epoxy resin), manufactured by DIC Corporation; "EPPN-502H" (trisphenol type epoxy resin), "NC7000L" (naphthol novolac type epoxy resin), "NC3000H", "NC3000", "NC3000L" manufactured by Nippon Kayaku Co., Ltd.; Examples include "NC3100" (biphenyl-type epoxy resin); "ESN475V" (naphthalene-type epoxy resin) and "ESN485" (naphthol novolac-type epoxy resin) manufactured by Nippon Steel Chemical & Material Co., Ltd.; "YX4000H", "YL6121" (biphenyl-type epoxy resin), "YX4000HK" (bixylenol-type epoxy resin), and "YX8800" (anthracene-type epoxy resin) manufactured by Mitsubishi Chemical Corporation; "PG-100" and "CG-500" manufactured by Osaka Gas Chemical Co., Ltd.; "YL7760" (bisphenol AF-type epoxy resin), "YL7800" (fluorene-type epoxy resin), "jER1010" (solid bisphenol A-type epoxy resin), and "jER1031S" (tetraphenylethane-type epoxy resin) manufactured by Mitsubishi Chemical Corporation; and "WHR-991S" (phenolphthalimidine-type epoxy resin) manufactured by Nippon Kayaku Co., Ltd. These may be used alone or in combination of two or more.

[0050] When a liquid epoxy resin and a solid epoxy resin are used in combination as component (B), the ratio by mass between them (liquid epoxy resin:solid epoxy resin) is preferably 1:0.1 to 1:20, more preferably 1:0.15 to 1:10, and particularly preferably 1:0.2 to 1:5.

[0051] The epoxy equivalent of component (B) is preferably 50 g / eq to 5000 g / eq, more preferably 50 g / eq to 3000 g / eq, even more preferably 80 g / eq to 2000 g / eq, and even more preferably 110 g / eq to 1000 g / eq. This range ensures that the cured product of the resin composition layer has sufficient crosslink density. The epoxy equivalent is the mass of an epoxy resin containing one equivalent of epoxy groups. This epoxy equivalent can be measured according to JIS K7236.

[0052] From the viewpoint of significantly achieving the desired effects of the present invention, the weight average molecular weight (Mw) of the component (B) is preferably 100 to 5000, more preferably 150 to 3000, and even more preferably 200 to 1500. The weight average molecular weight of the epoxy resin is a weight average molecular weight in terms of polystyrene measured by gel permeation chromatography (GPC).

[0053] From the viewpoint of obtaining a cured product exhibiting good mechanical strength and insulating reliability, the content of component (B) is preferably 1% by mass or more, more preferably 3% by mass or more, and even more preferably 5% by mass or more, based on 100% by mass of the nonvolatile components in the resin composition layer, and the upper limit is preferably 25% by mass or less, more preferably 20% by mass or less, and particularly preferably 15% by mass or less.

[0054] From the viewpoint of obtaining a cured product exhibiting good mechanical strength and insulating reliability, the content of component (B) is preferably 35% by mass or more, more preferably 40% by mass or more, and even more preferably 45% by mass or more, based on 100% by mass of the resin component in the resin composition layer, and the upper limit is preferably 75% by mass or less, more preferably 70% by mass or less, and particularly preferably 65% ​​by mass or less.

[0055] The resin component in the resin composition layer refers to the non-volatile components in the resin composition layer excluding the (A) inorganic filler.

[0056] -(C) Hardener- The resin composition layer may contain a (C) curing agent as the (C) component. This (C) curing agent as the (C) component does not include those corresponding to the above-mentioned (B) component. The (C) component usually has the function of reacting with the (B) component to cure the resin composition layer. The (C) component may be used alone or in combination of two or more types in any ratio.

[0057] As the component (C), a compound capable of reacting with the component (B) to cure the resin composition layer can be used. Examples of such curing agents include active ester curing agents, phenolic curing agents, carbodiimide curing agents, benzoxazine curing agents, acid anhydride curing agents, amine curing agents, and cyanate ester curing agents. Among these, the component (C) preferably contains one of an active ester curing agent, a phenolic curing agent, and a carbodiimide curing agent, more preferably one of an active ester curing agent and a phenolic curing agent, and even more preferably contains an active ester curing agent.

[0058] Examples of active ester curing agents include curing agents having one or more active ester groups per molecule. Among these, preferred active ester curing agents are compounds having two or more highly reactive ester groups per molecule, such as phenol esters, thiophenol esters, N-hydroxyamine esters, and esters of heterocyclic hydroxy compounds. The active ester curing agent is preferably one obtained by a condensation reaction between a carboxylic acid compound and / or a thiocarboxylic acid compound and a hydroxy compound and / or a thiol compound. In particular, from the viewpoint of improving heat resistance, active ester curing agents obtained from a carboxylic acid compound and a hydroxy compound are preferred, and active ester curing agents obtained from a carboxylic acid compound and a phenol compound and / or a naphthol compound are more preferred.

[0059] Examples of the carboxylic acid compound include benzoic acid, acetic acid, succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, terephthalic acid, and pyromellitic acid.

[0060] Examples of phenol compounds or naphthol compounds include hydroquinone, resorcinol, bisphenol A, bisphenol F, bisphenol S, phenolphthalene, methylated bisphenol A, methylated bisphenol F, methylated bisphenol S, phenol, o-cresol, m-cresol, p-cresol, catechol, α-naphthol, β-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucin, benzenetriol, dicyclopentadiene-type diphenol compounds, and phenol novolak. Here, "dicyclopentadiene-type diphenol compounds" refers to diphenol compounds obtained by condensing one dicyclopentadiene molecule with two phenol molecules.

[0061] Preferred specific examples of active ester curing agents include active ester compounds containing a dicyclopentadiene-type diphenol structure, active ester compounds containing a naphthalene structure, active ester compounds containing an acetylated product of phenol novolac, and active ester compounds containing a benzoylated product of phenol novolac. Among these, active ester compounds containing a naphthalene structure and active ester compounds containing a dicyclopentadiene-type diphenol structure are more preferred. The "dicyclopentadiene-type diphenol structure" refers to a divalent structure consisting of phenylene-dicyclopentylene-phenylene.

[0062] Commercially available active ester curing agents include active ester compounds containing a dicyclopentadiene-type diphenol structure, such as "EXB9451," "EXB9460," "EXB9460S," "HPC-8000," "HPC-8000H," "HPC-8000-65T," "HPC-8000H-65TM," "EXB-8000L," and "EXB-8000L-65TM" (manufactured by DIC Corporation); and active ester compounds containing a naphthalene structure, such as "HPC-8150-60T," "HPC-8150-62T," "EXB-8150-65T," "EXB-8100L-65T," "EXB9416- 70BK" and "EXB-8151-62T" (manufactured by DIC Corporation); an active ester compound containing an acetylated phenol novolac is "DC808" (manufactured by Mitsubishi Chemical Corporation); an active ester compound containing a benzoylated phenol novolac is "YLH1026" (manufactured by Mitsubishi Chemical Corporation); an active ester-based curing agent which is an acetylated phenol novolac is "DC808" (manufactured by Mitsubishi Chemical Corporation); and active ester-based curing agents which are benzoylated phenol novolac are "YLH1026" (manufactured by Mitsubishi Chemical Corporation), "YLH1030" (manufactured by Mitsubishi Chemical Corporation), and "YLH1048" (manufactured by Mitsubishi Chemical Corporation).

[0063] Examples of phenolic curing agents include curing agents having one or more, preferably two or more, hydroxyl groups bonded to an aromatic ring (such as a benzene ring or a naphthalene ring) in one molecule. Among these, compounds having a hydroxyl group bonded to a benzene ring are preferred. Furthermore, from the viewpoint of heat resistance and water resistance, phenolic curing agents having a novolac structure are preferred. Furthermore, from the viewpoint of filling ability, nitrogen-containing phenolic curing agents are preferred, triazine skeleton-containing phenolic curing agents are more preferred, and triazine skeleton-containing phenolic novolac curing agents are even more preferred.

[0064] Specific examples of phenol-based curing agents and naphthol-based curing agents include "MEH-7700," "MEH-7810," "MEH-7851," and "MEH-8000H" manufactured by Meiwa Kasei Co., Ltd.; "NHN," "CBN," and "GPH" manufactured by Nippon Kayaku Co., Ltd.; and "SN-170," "SN-180," "SN-190," "SN-475," "SN-485," "SN-495," "SN-495V," and "SN-375" manufactured by Nippon Steel Chemical & Material Co., Ltd. and "SN-395" manufactured by DIC Corporation; "TD-2090", "TD-2090-60M", "LA-7052", "LA-7054", "LA-1356", "LA-3018", "LA-3018-50P", "EXB-9500", "HPC-9500", "KA-1160", "KA-1163", and "KA-1165" manufactured by Gun-ei Chemical Co., Ltd.; and "GDP-6115L", "GDP-6115H", and "ELPC75" manufactured by Gun-ei Chemical Co., Ltd.

[0065] Specific examples of benzoxazine curing agents include "ODA-BOZ" manufactured by JFE Chemical Corporation, "HFB2006M" manufactured by Showa Polymer Co., Ltd., and "Pd" and "Fa" manufactured by Shikoku Chemicals Corporation.

[0066] Specific examples of carbodiimide curing agents include "V-03", "V-05", and "V-07" manufactured by Nisshinbo Chemical Inc.; and Stavaxol (registered trademark) P manufactured by Rhein Chemie.

[0067] Examples of acid anhydride curing agents include curing agents having one or more acid anhydride groups in one molecule. Specific examples of acid anhydride curing agents include phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, 4-methylhexahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylnadic anhydride, hydrogenated methylnadic anhydride, trialkyltetrahydrophthalic anhydride, dodecenyl succinic anhydride, 5-(2,5-dioxotetrahydro-3-furanyl)-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, trimellitic anhydride, pyromellitic anhydride, and benzophenone. Examples of suitable curing agents include tetracarboxylic dianhydrides, biphenyltetracarboxylic dianhydride, naphthalenetetracarboxylic dianhydride, oxydiphthalic dianhydride, 3,3'-4,4'-diphenylsulfonetetracarboxylic dianhydride, 1,3,3a,4,5,9b-hexahydro-5-(tetrahydro-2,5-dioxo-3-furanyl)-naphtho[1,2-C]furan-1,3-dione, ethylene glycol bis(anhydrotrimellitate), and polymeric acid anhydrides such as styrene-maleic acid resins (copolymers of styrene and maleic acid). Commercially available acid anhydride curing agents are also available, such as "MH-700" manufactured by New Japan Chemical Co., Ltd.

[0068] Examples of the amine curing agent include curing agents having one or more amino groups in one molecule, such as aliphatic amines, polyether amines, alicyclic amines, and aromatic amines. Among these, aromatic amines are preferred from the viewpoint of achieving the desired effects of the present invention. The amine curing agent is preferably a primary amine or a secondary amine, and more preferably a primary amine. Specific examples of amine-based curing agents include 4,4'-methylenebis(2,6-dimethylaniline), diphenyldiaminosulfone, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylsulfone, 3,3'-diaminodiphenylsulfone, m-phenylenediamine, m-xylylenediamine, diethyltoluenediamine, 4,4'-diaminodiphenyl ether, 3,3'-dimethyl-4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dihydroxybenzidine, and 2,2-bis(3-amino-4-hydroxybenzoyl). Examples of suitable amine curing agents include 4,4'-bis(4-aminophenoxy)biphenyl, bis(4-(4-aminophenoxy)phenyl)propane, 3,3-dimethyl-5,5-diethyl-4,4-diphenylmethanediamine, 2,2-bis(4-aminophenyl)propane, 2,2-bis(4-(4-aminophenoxy)phenyl)propane, 1,3-bis(3-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, bis(4-(4-aminophenoxy)phenyl)sulfone, and bis(4-(3-aminophenoxy)phenyl)sulfone. Commercially available amine curing agents may be used, such as "KAYABOND C-200S," "KAYABOND C-100," "KAYAHARD AA," "KAYAHARD AB," and "KAYAHARD AS" manufactured by Nippon Kayaku Co., Ltd., and "Epicure W" manufactured by Mitsubishi Chemical Corporation.

[0069] Examples of cyanate ester curing agents include bifunctional cyanate resins such as bisphenol A dicyanate, polyphenol cyanate, oligo(3-methylene-1,5-phenylene cyanate), 4,4'-methylenebis(2,6-dimethylphenyl cyanate), 4,4'-ethylidene diphenyl dicyanate, hexafluorobisphenol A dicyanate, 2,2-bis(4-cyanate)phenylpropane, 1,1-bis(4-cyanatephenylmethane), bis(4-cyanate-3,5-dimethylphenyl)methane, 1,3-bis(4-cyanatephenyl-1-(methylethylidene))benzene, bis(4-cyanatephenyl)thioether, and bis(4-cyanatephenyl)ether; polyfunctional cyanate resins derived from phenol novolac, cresol novolac, etc.; and prepolymers in which these cyanate resins are partially converted to triazine. Specific examples of cyanate ester curing agents include "PT30" and "PT60" manufactured by Lonza Japan Co., Ltd. (both are phenol novolac type multifunctional cyanate ester resins); "ULL-950S" (multifunctional cyanate ester resin); "BA230" and "BA230S75" (prepolymers in which part or all of bisphenol A dicyanate has been triazine converted to a trimer); and the like.

[0070] The range of the weight average molecular weight of the (C) curing agent may be the same as the range of the weight average molecular weight of the (B) epoxy resin.

[0071] When the number of epoxy groups in component (B) is taken as 1, the number of active groups in the (C) curing agent is preferably 0.01 or more, more preferably 0.05 or more, even more preferably 0.1 or more, and preferably 10 or less, more preferably 5 or less, and even more preferably 3 or less. Here, the "number of epoxy groups in component (A)" refers to the total value obtained by dividing the mass of the non-volatile components of component (B) present in the resin composition by the epoxy equivalent. Furthermore, the "number of active groups in (C) curing agent" refers to the total value obtained by dividing the mass of the non-volatile components of the (C) curing agent present in the resin composition by the active group equivalent. When the number of epoxy groups in component (B) is taken as 1, the desired effects of the present invention can be significantly achieved by having the number of active groups in the (C) curing agent within the above range.

[0072] The content of (C) the curing agent is preferably 1% by mass or more, more preferably 3% by mass or more, and even more preferably 5% by mass or more, and is preferably 20% by mass or less, more preferably 15% by mass or less, and even more preferably 10% by mass or less, assuming that the non-volatile components in the resin composition layer account for 100% by mass.

[0073] The content of the (C) curing agent is preferably 20% by mass or more, more preferably 25% by mass or more, and even more preferably 30% by mass or more, based on 100% by mass of the resin component in the resin composition layer, and the upper limit is preferably 50% by mass or less, more preferably 45% by mass or less, and particularly preferably 40% by mass or less.

[0074] When an active ester curing agent is included as the (C) curing agent, the content of the active ester curing agent is preferably 1% by mass or more, more preferably 3% by mass or more, and even more preferably 5% by mass or more, and is preferably 20% by mass or less, more preferably 15% by mass or less, and even more preferably 10% by mass or less, based on 100% by mass of the nonvolatile components in the resin composition layer. By adjusting the content of the active ester curing agent to fall within this range, it becomes easier to adjust the loss tangent to fall within the above range.

[0075] When an active ester curing agent (C) is included as the curing agent, the content of the active ester curing agent is preferably 5% by mass or more, more preferably 10% by mass or more, and even more preferably 15% by mass or more, based on 100% by mass of the resin component in the resin composition layer, from the viewpoint of significantly achieving the effects of the present invention. The upper limit is preferably 50% by mass or less, more preferably 45% by mass or less, and particularly preferably 40% by mass or less. By adjusting the content of the active ester curing agent to fall within this range, it becomes easier to adjust the loss tangent to fall within the above range.

[0076] -(D) Elastomer- The resin composition layer may contain a (D) elastomer as the (D) component. The (D) elastomer as the (D) component does not include those corresponding to the above-mentioned (B) to (C) components. The (D) component may be used alone or in a combination of two or more types in any ratio.

[0077] In the present invention, the (D) elastomer refers to a flexible resin, which is an amorphous resin component that dissolves in an organic solvent, and is preferably a resin having rubber elasticity or a resin that exhibits rubber elasticity by polymerizing with other components. Examples of rubber elasticity include resins that exhibit an elastic modulus of 1 GPa or less when subjected to a tensile test in accordance with Japanese Industrial Standards (JIS K7161) at a temperature of 25°C and a humidity of 40%RH.

[0078] In one embodiment, component (D) is preferably a resin having one or more structures selected from a polybutadiene structure, a polysiloxane structure, a poly(meth)acrylate structure, a polyalkylene structure, a polyalkyleneoxy structure, a polyisoprene structure, a polyisobutylene structure, and a polycarbonate structure in the molecule, and from the viewpoint of obtaining a flexible material, a resin having one or more structures selected from a polybutadiene structure and a polycarbonate structure is more preferable. Note that "(meth)acrylate" refers to methacrylate and acrylate.

[0079] In another embodiment, component (D) is preferably one or more resins selected from resins having a glass transition temperature (Tg) of 25°C or lower and resins that are liquid at 25°C or lower. The glass transition temperature of resins having a glass transition temperature (Tg) of 25°C or lower is preferably 20°C or lower, more preferably 15°C or lower. There are no particular restrictions on the lower limit of the glass transition temperature, but it can usually be -15°C or higher. Furthermore, resins that are liquid at 25°C are preferably resins that are liquid at 20°C or lower, more preferably resins that are liquid at 15°C or lower.

[0080] In a more preferred embodiment, component (D) is at least one resin selected from resins that have a glass transition temperature of 25°C or lower and are liquid at 25°C, and that have one or more structures in the molecule selected from a polybutadiene structure, a polysiloxane structure, a poly(meth)acrylate structure, a polyalkylene structure, a polyalkyleneoxy structure, a polyisoprene structure, a polyisobutylene structure, and a polycarbonate structure.

[0081] The polybutadiene structure includes not only a structure formed by polymerizing butadiene but also a structure formed by hydrogenating the butadiene structure. The butadiene structure may be partially or entirely hydrogenated. Furthermore, the polybutadiene structure may be contained in the main chain or in the side chain of component (D).

[0082] Preferred examples of polybutadiene resins include hydrogenated polybutadiene skeleton-containing resins, hydroxy group-containing polybutadiene resins, phenolic hydroxyl group-containing polybutadiene resins, carboxy group-containing polybutadiene resins, acid anhydride group-containing polybutadiene resins, epoxy group-containing polybutadiene resins, isocyanate group-containing polybutadiene resins, and urethane group-containing polybutadiene resins. Among these, phenolic hydroxyl group-containing polybutadiene resins are more preferred. Here, "hydrogenated polybutadiene skeleton-containing resin" refers to a resin in which at least a portion of the polybutadiene skeleton is hydrogenated, and does not necessarily have to be a resin in which the polybutadiene skeleton is completely hydrogenated. Examples of hydrogenated polybutadiene skeleton-containing resins include hydrogenated polybutadiene skeleton-containing epoxy resins. Furthermore, examples of phenolic hydroxyl group-containing polybutadiene resins include resins having a polybutadiene structure and phenolic hydroxyl groups.

[0083] Specific examples of polybutadiene resins, which are resins having a polybutadiene structure in the molecule, include "Ricon 657" (epoxy group-containing polybutadiene), "Ricon 130MA8", "Ricon 130MA13", "Ricon 130MA20", "Ricon 131MA5", "Ricon 131MA10", "Ricon 131MA17", "Ricon 131MA20", and "Ricon Examples include "184MA6" (polybutadiene containing an acid anhydride group), "GQ-1000" (polybutadiene with introduced hydroxyl and carboxyl groups), "G-1000", "G-2000", "G-3000" (polybutadiene with hydroxyl groups at both ends), "GI-1000", "GI-2000", "GI-3000" (hydrogenated polybutadiene with hydroxyl groups at both ends), Daicel Corporation's "PB3600" and "PB4700" (polybutadiene-based epoxy compounds), "Epofriend A1005", "Epofriend A1010", and "Epofriend A1020" (epoxy compounds of styrene, butadiene and styrene block copolymers), and Nagase ChemteX Corporation's "FCA-061L" (hydrogenated polybutadiene-based epoxy compound) and "R-45EPT" (polybutadiene-based epoxy compound).

[0084] Further, examples of preferred polybutadiene resins include linear polyimides (such as those described in JP 2006-37083 A and WO 2008 / 153208 A) made from hydroxyl-terminated polybutadiene, diisocyanate compounds, and polybasic acids or their anhydrides. The polyimide resin preferably has a polybutadiene structure content of 60% to 95% by mass, more preferably 75% to 85% by mass. For details of the polyimide resin, please refer to the descriptions in JP 2006-37083 A and WO 2008 / 153208 A, the contents of which are incorporated herein by reference.

[0085] The number average molecular weight of the hydroxyl group-terminated polybutadiene is preferably 500 to 5,000, and more preferably 1,000 to 3,000. The hydroxyl group equivalent of the hydroxyl group-terminated polybutadiene is preferably 250 to 1,250.

[0086] Examples of diisocyanate compounds include aromatic diisocyanates such as toluene-2,4-diisocyanate, toluene-2,6-diisocyanate, xylylene diisocyanate, and diphenylmethane diisocyanate; aliphatic diisocyanates such as hexamethylene diisocyanate; and alicyclic diisocyanates such as isophorone diisocyanate. Among these, aromatic diisocyanates are preferred, and toluene-2,4-diisocyanate is more preferred.

[0087] Examples of polybasic acids or anhydrides thereof include tetrabasic acids such as ethylene glycol bistrimellitic acid, pyromellitic acid, benzophenone tetracarboxylic acid, biphenyl tetracarboxylic acid, naphthalene tetracarboxylic acid, 5-(2,5-dioxotetrahydrofuryl)-3-methyl-cyclohexene-1,2-dicarboxylic acid, and 3,3'-4,4'-diphenylsulfone tetracarboxylic acid, and their anhydrides; tribasic acids such as trimellitic acid and cyclohexane tricarboxylic acid, and their anhydrides; and 1,3,3a,4,5,9b-hexahydro-5-(tetrahydro-2,5-dioxo-3-furanyl)-naphtho(1,2-C)furan-1,3-dione.

[0088] The polybutadiene structure also includes a polystyrene structure obtained by polymerizing styrene.

[0089] Specific examples of polystyrene resins, which are resins having a polystyrene structure in the molecule, include styrene-butadiene-styrene block copolymer (SBS), styrene-isoprene-styrene block copolymer (SIS), styrene-ethylene-butylene-styrene block copolymer (SEBS), styrene-ethylene-propylene-styrene block copolymer (SEPS), styrene-ethylene-ethylene-propylene-styrene block copolymer (SEEPS), styrene-butadiene-butylene-styrene block copolymer (SBBS), styrene-butadiene diblock copolymer, hydrogenated styrene-butadiene block copolymer, hydrogenated styrene-isoprene block copolymer, and hydrogenated styrene-butadiene random copolymer.

[0090] The polystyrene resin may be a commercially available product, and examples thereof include hydrogenated styrene-based thermoplastic elastomers "H1041," "Tuftec H1043," "Tuftec P2000," and "Tuftec MP10" (manufactured by Asahi Kasei Corporation); epoxidized styrene-butadiene thermoplastic elastomers "Epofriend AT501" and "CT310" (manufactured by Daicel Corporation); modified styrene-based elastomer having a hydroxyl group "Septon HG252" (manufactured by Kuraray Co., Ltd.); modified styrene-based elastomer having a carboxyl group "Tuftec N503M," modified styrene-based elastomer having an amino group "Tuftec N501," modified styrene-based elastomer having an acid anhydride group "Tuftec M1913" (manufactured by Asahi Kasei Chemicals Corporation); and unmodified styrene-based elastomer "Septon S8104" (manufactured by Kuraray Co., Ltd.).

[0091] The polysiloxane structure is a structure containing siloxane bonds, and is found in, for example, silicone rubber. The polysiloxane structure may be contained in the main chain or a side chain of component (D).

[0092] Specific examples of polysiloxane resins, which are resins having a polysiloxane structure in the molecule, include "SMP-2006," "SMP-2003PGMEA," and "SMP-5005PGMEA" manufactured by Shin-Etsu Silicones Co., Ltd., amine-terminated polysiloxanes, and linear polyimides made from tetrabasic acid anhydrides (WO 2010 / 053185).

[0093] The poly(meth)acrylate structure is a structure formed by polymerizing acrylic acid or an acrylic acid ester, and also includes a structure formed by polymerizing methacrylic acid or a methacrylic acid ester. The (meth)acrylate structure may be contained in the main chain or a side chain of component (D).

[0094] Preferred examples of poly(meth)acrylate resins, which are resins having a poly(meth)acrylate structure in the molecule, include hydroxy group-containing poly(meth)acrylate resins, phenolic hydroxy group-containing poly(meth)acrylate resins, carboxy group-containing poly(meth)acrylate resins, acid anhydride group-containing poly(meth)acrylate resins, epoxy group-containing poly(meth)acrylate resins, isocyanate group-containing poly(meth)acrylate resins, and urethane group-containing poly(meth)acrylate resins.

[0095] Specific examples of poly(meth)acrylate resins include Nagase ChemteX's Teisan Resin "SG-70L," "SG-708-6," "WS-023," "SG-700AS," and "SG-280TEA" (carboxyl group-containing acrylic ester copolymer resin, acid value 5 to 34 mgKOH / g, weight average molecular weight 400,000 to 900,000, Tg -30°C to 5°C), "SG-80H," "SG-80H-3," and "SG-P3" (epoxy group-containing acrylic ester copolymer resin, epoxy equivalent 4761 to 14285 g / eq, weight average molecular weight 350,000). Examples include "SG-600TEA" and "SG-790" (hydroxy group-containing acrylic ester copolymer resin, hydroxyl value 20-40 mgKOH / g, weight average molecular weight 500,000-1,200,000, Tg -37°C to -32°C) manufactured by Negami Chemical Industrial Co., Ltd., as well as "ME-2000" and "W-116.3" (carboxy group-containing acrylic ester copolymer resin), "W-197C" (hydroxy group-containing acrylic ester copolymer resin), "KG-25" and "KG-3000" (epoxy group-containing acrylic ester copolymer resin).

[0096] The polyalkylene structure preferably has a specific number of carbon atoms. The specific number of carbon atoms in the polyalkylene structure is preferably 2 or more, more preferably 3 or more, and particularly preferably 5 or more, and is preferably 15 or less, more preferably 10 or less, and particularly preferably 6 or less. Furthermore, the polyalkylene structure may be contained in the main chain or a side chain of component (D).

[0097] The polyalkyleneoxy structure preferably has a specific number of carbon atoms. The specific number of carbon atoms in the polyalkyleneoxy structure is preferably 2 or more, preferably 3 or more, more preferably 5 or more, and preferably 15 or less, more preferably 10 or less, and particularly preferably 6 or less. The polyalkyleneoxy structure may be contained in the main chain or a side chain of component (D).

[0098] Specific examples of polyalkylene resins, which are resins having a polyalkylene structure in the molecule, and polyalkyleneoxy resins, which are resins having a polyalkyleneoxy structure in the molecule, include "PTXG-1000" and "PTXG-1800" manufactured by Asahi Kasei Fibers Corporation, "YX-7180" (a resin containing an alkylene structure with an ether bond) manufactured by Mitsubishi Chemical Corporation, "EXA-4850-150," "EXA-4816," and "EXA-4822" manufactured by DIC Corporation, "EP-4000," "EP-4003," "EP-4010," and "EP-4011" manufactured by ADEKA Corporation, "BEO-60E" and "BPO-20E" manufactured by New Japan Chemical Co., Ltd., and "YL7175" and "YL7410" manufactured by Mitsubishi Chemical Corporation.

[0099] The polyisoprene structure may be contained in either the main chain or the side chain of component (D). Specific examples of polyisoprene resins that have a polyisoprene structure in the molecule include "KL-610" and "KL-613" manufactured by Kuraray Co., Ltd.

[0100] The polyisobutylene structure may be contained in either the main chain or the side chain of component (D). Specific examples of polyisobutylene resins that have a polyisobutylene structure in the molecule include "SIBSTAR-073T" (styrene-isobutylene-styrene triblock copolymer) and "SIBSTAR-042D" (styrene-isobutylene diblock copolymer), both manufactured by Kaneka Corporation.

[0101] The polycarbonate structure may be contained in the main chain or in a side chain of component (D).

[0102] Preferred examples of polycarbonate resins, which are resins having a polycarbonate structure in the molecule, include hydroxy group-containing polycarbonate resins, phenolic hydroxy group-containing polycarbonate resins, carboxy group-containing polycarbonate resins, acid anhydride group-containing polycarbonate resins, epoxy group-containing polycarbonate resins, isocyanate group-containing polycarbonate resins, and urethane group-containing polycarbonate resins.

[0103] Specific examples of polycarbonate resins include "T6002" and "T6001" (polycarbonate diols) manufactured by Asahi Kasei Chemicals Corporation, and "C-1090", "C-2090", and "C-3090" (polycarbonate diols) manufactured by Kuraray Co., Ltd.

[0104] Preferred examples of polycarbonate resins include linear polyimides made from hydroxyl-terminated polycarbonates, diisocyanate compounds, and polybasic acids or their anhydrides. The linear polyimides have a urethane structure and a polycarbonate structure. The polycarbonate structure content of the polyimide resin is preferably 60% to 95% by mass, more preferably 75% to 85% by mass. For details of the polyimide resin, please refer to the description in International Publication No. 2016 / 129541, the contents of which are incorporated herein by reference.

[0105] The number average molecular weight of the hydroxyl group-terminated polycarbonate is preferably 500 to 5,000, more preferably 1,000 to 3,000. The hydroxyl group equivalent of the hydroxyl group-terminated polycarbonate is preferably 250 to 1,250.

[0106] Component (D) preferably further contains an imide structure, which can improve the heat resistance of component (D) and effectively increase crack resistance.

[0107] Component (D) may have a linear, branched, or cyclic structure, but is preferably linear.

[0108] Component (D) preferably further contains a functional group capable of reacting with component (B). This functional group includes a reactive group that appears upon heating. By including a functional group in component (D), the mechanical strength of the cured resin composition layer can be improved.

[0109] Examples of the functional group include a carboxy group, a hydroxy group, an acid anhydride group, a phenolic hydroxyl group, an epoxy group, an isocyanate group, and a urethane group. Among these, from the viewpoint of significantly achieving the effects of the present invention, the functional group preferably has one or more functional groups selected from a hydroxyl group, an acid anhydride group, a phenolic hydroxyl group, an epoxy group, an isocyanate group, and a urethane group, and a phenolic hydroxyl group is particularly preferred.

[0110] From the viewpoint of exhibiting flexibility, component (D) preferably has a high molecular weight. The specific number average molecular weight Mn of component (D) is preferably 4000 or more, more preferably 4500 or more, even more preferably 5000 or more, still more preferably more than 5000, particularly preferably 5500 or more, and preferably 100000 or less, more preferably 95000 or less, particularly preferably 90000 or less. The number average molecular weight Mn of component (D) is the number average molecular weight in terms of polystyrene measured using GPC (gel permeation chromatography).

[0111] From the viewpoint of obtaining flexibility, the weight average molecular weight of component (D) is preferably 5,500 to 100,000, more preferably 10,000 to 90,000, and even more preferably 15,000 to 80,000. The weight average molecular weight of component (D) is a weight average molecular weight in terms of polystyrene measured by gel permeation chromatography (GPC).

[0112] When component (D) has a functional group, the functional group equivalent of component (D) is preferably 100 or more, more preferably 200 or more, even more preferably 1000 or more, particularly preferably 2500 or more, and preferably 50,000 or less, more preferably 30,000 or less, even more preferably 10,000 or less, particularly preferably 5,000 or less. The functional group equivalent is the number of grams of resin containing 1 gram equivalent of functional group. For example, the epoxy group equivalent can be measured according to JIS K7236. Furthermore, for example, the hydroxyl group equivalent can be calculated by dividing the molecular weight of KOH by the hydroxyl value measured according to JIS K1557-1.

[0113] The content of the (D) elastomer is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, and even more preferably 1% by mass or more, and is preferably 5% by mass or less, more preferably 3% by mass or less, and even more preferably 2% by mass or less, assuming that the non-volatile components in the resin composition layer are 100% by mass.

[0114] The content of the (D) elastomer is preferably 3% by mass or more, more preferably 5% by mass or more, and even more preferably 8% by mass or more, and is preferably 25% by mass or less, more preferably 20% by mass or less, and even more preferably 15% by mass or less, assuming that the resin component in the resin composition layer is 100% by mass.

[0115] -(E) Thermoplastic resin- The resin composition layer may contain a thermoplastic resin (E) as the component (E). The thermoplastic resin (E) as the component (E) does not include those corresponding to the above-mentioned components (B) to (D). The component (E) may be used alone or in combination of two or more.

[0116] The weight average molecular weight (Mw) of component (E) is preferably 5,000 or more, more preferably greater than 5,000, more preferably 8,000 or more, and even more preferably 10,000 or more. There are no particular limitations on the upper limit of Mw, but it is preferably 100,000 or less, more preferably 80,000 or less, and even more preferably 50,000 or less. The Mw of component (E) can be measured as a polystyrene-equivalent value by gel permeation chromatography (GPC).

[0117] Examples of the component (E) include thermoplastic resins such as phenoxy resins, polyimide resins, polycarbonate resins, polyvinyl acetal resins, polyolefin resins, polyamideimide resins, polyetherimide resins, polysulfone resins, polyethersulfone resins, polyphenylene ether resins, polyetheretherketone resins, polystyrene resins, and polyester resins. Among these, from the viewpoint of significantly achieving the effects of the present invention, the component (E) preferably contains at least one selected from phenoxy resins, polyimide resins, and polycarbonate resins, and more preferably phenoxy resins.

[0118] Examples of phenoxy resins include phenoxy resins having one or more skeletons selected from the group consisting of bisphenol A, bisphenol F, bisphenol S, bisphenolacetophenone, novolac, biphenyl, fluorene, dicyclopentadiene, norbornene, naphthalene, anthracene, adamantane, terpene, and trimethylcyclohexane. The terminal of the phenoxy resin may be any functional group such as a phenolic hydroxyl group or an epoxy group.

[0119] Commercially available phenoxy resins include, for example, "1256" and "4250" manufactured by Mitsubishi Chemical Corporation (both of which are phenoxy resins containing a bisphenol A skeleton); "YX8100" manufactured by Mitsubishi Chemical Corporation (phenoxy resin containing a bisphenol S skeleton); "YX6954" manufactured by Mitsubishi Chemical Corporation (phenoxy resin containing a bisphenol acetophenone skeleton); "FX280" and "FX293" manufactured by Nippon Steel Chemical & Material Co., Ltd.; and "YL7500BH30," "YX6954BH30," "YX7553," "YX7553BH30," "YL7769BH30," "YL6794," "YL7213," "YL7290," and "YL7482" manufactured by Mitsubishi Chemical Corporation.

[0120] The polyimide resin may be a resin having an imide structure. Polyimide resins are generally obtained by an imidization reaction between a diamine compound and an acid anhydride. Commercially available polyimide resins may be used, such as "Rikacoat SN20" and "Rikacoat PN20" manufactured by New Japan Chemical Co., Ltd.

[0121] Polycarbonate resins are resins having a carbonate structure. Examples of such resins include carbonate resins without reactive groups, hydroxyl group-containing carbonate resins, phenolic hydroxyl group-containing carbonate resins, carboxyl group-containing carbonate resins, acid anhydride group-containing carbonate resins, isocyanate group-containing carbonate resins, urethane group-containing carbonate resins, and epoxy group-containing carbonate resins. Here, the reactive group refers to a functional group that can react with other components, such as a hydroxy group, a phenolic hydroxyl group, a carboxy group, an acid anhydride group, an isocyanate group, a urethane group, or an epoxy group.

[0122] Commercially available polycarbonate resins can be used, including "FPC0220" and "FPC2136" manufactured by Mitsubishi Gas Chemical Company, "T6002" and "T6001" (polycarbonate diols) manufactured by Asahi Kasei Chemicals Corporation, and "C-1090," "C-2090," and "C-3090" (polycarbonate diols) manufactured by Kuraray Co., Ltd.

[0123] The content of component (E) is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, and even more preferably 0.1% by mass or more, and is preferably 5% by mass or less, more preferably 3% by mass or less, and even more preferably 2% by mass or less, assuming that the non-volatile components in the resin composition layer are 100% by mass.

[0124] The content of component (E) is preferably 0.3% by mass or more, more preferably 0.5% by mass or more, and even more preferably 0.8% by mass or more, and is preferably 10% by mass or less, more preferably 9% by mass or less, and even more preferably 8% by mass or less, assuming that the resin component in the resin composition layer is 100% by mass.

[0125] When an active ester-based curing agent (C) is contained in the resin composition layer, the loss tangent value may become large. In the present invention, when an active ester-based curing agent is used as the curing agent, the loss tangent value can be easily adjusted to fall within the above range by containing either (D) an elastomer or (E) a thermoplastic resin in the resin composition layer in addition to (A) an inorganic filler and (B) an epoxy resin.

[0126] The ratio of the content of the active ester curing agent to the total content of the (D) elastomer and the (E) thermoplastic resin {(the content of the active ester curing agent when the non-volatile components are taken as 100% by mass) / (the total content of the (D) elastomer and the (E) thermoplastic resin when the (D) non-volatile components are taken as 100% by mass)} is preferably 0.5 or more, more preferably 1 or more, and even more preferably 1.5 or more, and is preferably 40 or less, more preferably 30 or less, and particularly preferably 20 or less, 10 or less, or 5 or less.

[0127] The total content of the (B), (C), (D), and (E) components is preferably 5% by mass or more, more preferably 8% by mass or more, even more preferably 10% by mass or more, or 15% by mass or more, and is preferably 35% by mass or less, more preferably 30% by mass or less, and even more preferably 25% by mass or less, assuming that the non-volatile components in the resin composition layer are 100% by mass.

[0128] -(F) Curing accelerator- The resin composition layer may contain a curing accelerator (F) as the component (F). The curing accelerator (F) as the component (E) does not include those corresponding to the above-mentioned components (B) to (E). By including the component (F), it becomes possible to further accelerate the curing of the component (B). The component (F) may be used alone or in combination of two or more.

[0129] Examples of component (F) include amine-based curing accelerators, imidazole-based curing accelerators, phosphorus-based curing accelerators, urea-based curing accelerators, guanidine-based curing accelerators, metal-based curing accelerators, etc. Among these, curing accelerators selected from amine-based curing accelerators and imidazole-based curing accelerators are preferred, and amine-based curing accelerators are particularly preferred.

[0130] Examples of the amine-based curing accelerator include trialkylamines such as triethylamine and tributylamine, 4-dimethylaminopyridine, benzyldimethylamine, 2,4,6-tris(dimethylaminomethyl)phenol, and 1,8-diazabicyclo(5,4,0)-undecene.

[0131] As the amine-based curing accelerator, commercially available products may be used, for example, "MY-25" manufactured by Ajinomoto Fine-Techno Co., Ltd.

[0132] As the imidazole-based curing accelerator, commercially available products may be used, such as "1B2PZ", "2MZA-PW", "2PHZ-PW", and "C11Z-A" manufactured by Shikoku Chemical Industry Co., Ltd., and "P200-H50" manufactured by Mitsubishi Chemical Corporation.

[0133] Examples of the phosphorus-based curing accelerator include aliphatic phosphonium salts such as tetrabutylphosphonium bromide, tetrabutylphosphonium chloride, tetrabutylphosphonium acetate, tetrabutylphosphonium decanoate, tetrabutylphosphonium laurate, bis(tetrabutylphosphonium)pyromellitate, tetrabutylphosphonium hydrogenhexahydrophthalate, tetrabutylphosphonium 2,6-bis[(2-hydroxy-5-methylphenyl)methyl]-4-methylphenolate, and di-tert-butyldimethylphosphonium tetraphenylborate; methyltriphenylphosphonium bromide, ethyltriphenylphosphonium bromide, propyltriphenylphosphonium bromide, butyltriphenylphosphonium bromide, benzyltriphenylphosphonium chloride, tetraphenylphosphonium bromide, p-tolyltriphenylphosphonium tetra-p-tolylborate, and tetraphenylphosphonium tetra-p-tolylborate. aromatic phosphonium salts such as tetraphenylborate, tetraphenylphosphonium tetra-p-tolylborate, triphenylethylphosphonium tetraphenylborate, tris(3-methylphenyl)ethylphosphonium tetraphenylborate, tris(2-methoxyphenyl)ethylphosphonium tetraphenylborate, (4-methylphenyl)triphenylphosphonium thiocyanate, tetraphenylphosphonium thiocyanate, and butyltriphenylphosphonium thiocyanate; aromatic phosphine-borane complexes such as triphenylphosphine-triphenylborane; aromatic phosphine-quinone adducts such as triphenylphosphine-p-benzoquinone adduct; aliphatic phosphines such as tributylphosphine, tri-tert-butylphosphine, trioctylphosphine, di-tert-butyl(2-butenyl)phosphine, di-tert-butyl(3-methyl-2-butenyl)phosphine, and tricyclohexylphosphine;Dibutylphenylphosphine, di-tert-butylphenylphosphine, methyldiphenylphosphine, ethyldiphenylphosphine, butyldiphenylphosphine, diphenylcyclohexylphosphine, triphenylphosphine, tri-o-tolylphosphine, tri-m-tolylphosphine, tri-p-tolylphosphine, tris(4-ethylphenyl)phosphine, tris(4-propylphenyl)phosphine, tris(4-isopropylphenyl)phosphine, tris(4-butylphenyl)phosphine, tris(4-tert-butylphenyl)phosphine, tris(2,4-dimethylphenyl)phosphine, tris(2,5-dimethylphenyl)phosphine, tris(2,6-dimethylphenyl)phosphine aromatic phosphines such as benzene, tris(3,5-dimethylphenyl)phosphine, tris(2,4,6-trimethylphenyl)phosphine, tris(2,6-dimethyl-4-ethoxyphenyl)phosphine, tris(2-methoxyphenyl)phosphine, tris(4-methoxyphenyl)phosphine, tris(4-ethoxyphenyl)phosphine, tris(4-tert-butoxyphenyl)phosphine, diphenyl-2-pyridylphosphine, 1,2-bis(diphenylphosphino)ethane, 1,3-bis(diphenylphosphino)propane, 1,4-bis(diphenylphosphino)butane, 1,2-bis(diphenylphosphino)acetylene, and 2,2'-bis(diphenylphosphino)diphenyl ether;

[0134] Examples of the urea-based curing accelerator include 1,1-dimethylurea; aliphatic dimethylureas such as 1,1,3-trimethylurea, 3-ethyl-1,1-dimethylurea, 3-cyclohexyl-1,1-dimethylurea, and 3-cyclooctyl-1,1-dimethylurea; 3-phenyl-1,1-dimethylurea, 3-(4-chlorophenyl)-1,1-dimethylurea, 3-(3,4-dichlorophenyl)-1,1-dimethylurea, 3-(3-chloro-4-methylphenyl)-1,1-dimethylurea, 3-(2-methylphenyl)-1,1-dimethylurea, 3-(4-methylphenyl)-1,1-dimethylurea, and 3-(3,4-dimethylphenyl)-1,1-dimethylurea. aromatic dimethylureas such as toluene bis(dimethylurea), 3-(4-isopropylphenyl)-1,1-dimethylurea, 3-(4-methoxyphenyl)-1,1-dimethylurea, 3-(4-nitrophenyl)-1,1-dimethylurea, 3-[4-(4-methoxyphenoxy)phenyl]-1,1-dimethylurea, 3-[4-(4-chlorophenoxy)phenyl]-1,1-dimethylurea, 3-[3-(trifluoromethyl)phenyl]-1,1-dimethylurea, N,N-(1,4-phenylene)bis(N',N'-dimethylurea), and N,N-(4-methyl-1,3-phenylene)bis(N',N'-dimethylurea) [toluene bisdimethylurea].

[0135] Examples of guanidine curing accelerators include dicyandiamide, 1-methylguanidine, 1-ethylguanidine, 1-cyclohexylguanidine, 1-phenylguanidine, 1-(o-tolyl)guanidine, dimethylguanidine, diphenylguanidine, trimethylguanidine, tetramethylguanidine, pentamethylguanidine, 1,5,7-triazabicyclo[4.4.0]dec-5-ene, 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene, 1-methylbiguanide, 1-ethylbiguanide, 1-n-butylbiguanide, 1-n-octadecylbiguanide, 1,1-dimethylbiguanide, 1,1-diethylbiguanide, 1-cyclohexylbiguanide, 1-allylbiguanide, 1-phenylbiguanide, and 1-(o-tolyl)biguanide.

[0136] Examples of the imidazole curing accelerator include 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, and 1-benzyl-2-methylimidazole. Phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-phenylimidazolium trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6-[2'-methylimidazolyl -(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-undecylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct , 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2,3-dihydro-1H-pyrrolo[1,2-a]benzimidazole, 1-dodecyl-2-methyl-3-benzylimidazolium chloride, 2-methylimidazoline, 2-phenylimidazoline, and other imidazole compounds, as well as adducts of imidazole compounds with epoxy resins.

[0137] Examples of metal-based curing accelerators include organometallic complexes or organometallic salts of metals such as cobalt, copper, zinc, iron, nickel, manganese, and tin. Specific examples of organometallic complexes include organic cobalt complexes such as cobalt(II) acetylacetonate and cobalt(III) acetylacetonate, organic copper complexes such as copper(II) acetylacetonate, organic zinc complexes such as zinc(II) acetylacetonate, organic iron complexes such as iron(III) acetylacetonate, organic nickel complexes such as nickel(II) acetylacetonate, and organic manganese complexes such as manganese(II) acetylacetonate. Examples of organometallic salts include zinc octoate, tin octoate, zinc naphthenate, cobalt naphthenate, tin stearate, and zinc stearate.

[0138] The content of component (F) is preferably 0.01% by mass or more, more preferably 0.02% by mass or more, and even more preferably 0.03% by mass or more, and is preferably 1% by mass or less, more preferably 0.5% by mass or less, and even more preferably 0.1% by mass or less, assuming that the non-volatile components in the resin composition layer are 100% by mass.

[0139] The content of the (F) component is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, and even more preferably 0.1% by mass or more, and is preferably 5% by mass or less, more preferably 3% by mass or less, and even more preferably 1% by mass or less, assuming that the resin component in the resin composition layer is 100% by mass.

[0140] -(G) Radical polymerizable resin- The resin composition layer may contain a (G) radical polymerizable resin as the (G) component. The (G) radical polymerizable resin as the (G) component excludes those corresponding to the (B) to (F) components. The (G) component may be used alone or in combination of two or more types.

[0141] The (G) radical polymerizable resin may contain an ethylenically unsaturated bond. Therefore, the (G) radical polymerizable resin may have a radical polymerizable group containing an ethylenically unsaturated bond. Examples of the radical polymerizable group include unsaturated hydrocarbon groups such as vinyl, allyl, styryl, 1-propenyl, 3-cyclohexenyl, 3-cyclopentenyl, 2-vinylphenyl, 3-vinylphenyl, and 4-vinylphenyl; and α,β-unsaturated carbonyl groups such as acryloyl and methacryloyl. Among these, the ethylenically unsaturated bond is preferably one or more selected from the group consisting of allyl, styryl, vinylphenyl, acryloyl, and methacryloyl. The (G) radical polymerizable resin preferably has two or more radical polymerizable groups.

[0142] (G) Examples of radically polymerizable resins include (meth)acrylic radically polymerizable resins, styrene radically polymerizable resins, and allyl radically polymerizable resins, with (meth)acrylic radically polymerizable resins being preferred.

[0143] The (meth)acrylic radical polymerizable resin is, for example, a compound having one or more, preferably two or more, acryloyl groups and / or methacryloyl groups. Examples of the (meth)acrylic radical polymerizable resin include cyclohexane-1,4-dimethanol di(meth)acrylate, cyclohexane-1,3-dimethanol di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,8-octanediol di(meth)acrylate, 1,9-nonane diol di(meth)acrylate, and the like. Low molecular weight (molecular weight less than 1000) aliphatic (meth)acrylic acid ester compounds such as diol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, trimethylolethane tri(meth)acrylate, glycerin tri(meth)acrylate, and pentaerythritol tetra(meth)acrylate; dioxane glycol di(meth)acrylate, 3,6-dioxa-1,8-octanediol di(meth)acrylate, ) acrylate, 3,6,9-trioxaundecane-1,11-diol di(meth)acrylate, polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, 9,9-bis[4-(2-acryloyloxyethoxy)phenyl]fluorene, ethoxylated bisphenol A di(meth)acrylate, propoxylated bisphenol A di(meth)acrylate, and other low molecular weight (molecular weight less than 1000) ether-containing (meth)acrylic acid ester compounds; low molecular weight (molecular weight less than 1000) isocyanurate-containing (meth)acrylic acid ester compounds such as tris(3-hydroxypropyl)isocyanurate tri(meth)acrylate, tris(2-hydroxyethyl)isocyanurate tri(meth)acrylate, and ethoxylated isocyanuric acid tri(meth)acrylate; and high molecular weight (molecular weight 1000 or more) acrylic acid ester compounds such as (meth)acrylic-modified polyphenylene ether resins.Commercially available (meth)acrylic radical polymerizable resins include, for example, "A-DOG" (dioxane glycol diacrylate) manufactured by Shin-Nakamura Chemical Co., Ltd., "DCP-A" (tricyclodecane dimethanol diacrylate) and "DCP" (tricyclodecane dimethanol dimethacrylate) manufactured by Kyoeisha Chemical Co., Ltd., "KAYARAD R-684" (tricyclodecane dimethanol diacrylate) and "KAYARAD R-604" (dioxane glycol diacrylate) manufactured by Nippon Kayaku Co., Ltd., and "SA9000" and "SA9000-111" (methacrylic-modified polyphenylene ether) manufactured by SABIC Innovative Plastics.

[0144] The styrene radical polymerizable resin is, for example, a compound having one or more, preferably two or more, vinyl groups directly bonded to an aromatic carbon atom. Examples of the styrene radical polymerizable resin include low molecular weight (molecular weight less than 1000) styrene compounds such as divinylbenzene, 2,4-divinyltoluene, 2,6-divinylnaphthalene, 1,4-divinylnaphthalene, 4,4'-divinylbiphenyl, 1,2-bis(4-vinylphenyl)ethane, 2,2-bis(4-vinylphenyl)propane, and bis(4-vinylphenyl)ether; and high molecular weight (molecular weight 1000 or more) styrene compounds such as vinylbenzyl-modified polyphenylene ether resin and styrene-divinylbenzene copolymer. Commercially available styrene-based radical polymerizable resins include, for example, "ODV-XET(X03)", "ODV-XET(X04)", and "ODV-XET(X05)" (styrene-divinylbenzene copolymers) manufactured by Nippon Steel Chemical & Material Co., Ltd., and "OPE-2St 1200" and "OPE-2St 2200" (vinylbenzyl-modified polyphenylene ether resins) manufactured by Mitsubishi Gas Chemical Company, Inc.

[0145] The allyl radical polymerizable resin is, for example, a compound having one or more, preferably two or more, allyl groups. Examples of allyl radical polymerizable resins include aromatic carboxylic acid allyl ester compounds such as diallyl diphenate, triallyl trimellitate, diallyl phthalate, diallyl isophthalate, diallyl terephthalate, diallyl 2,6-naphthalenedicarboxylate, and diallyl 2,3-naphthalenecarboxylate; isocyanuric acid allyl ester compounds such as 1,3,5-triallyl isocyanurate and 1,3-diallyl-5-glycidyl isocyanurate; epoxy-containing aromatic allyl compounds such as 2,2-bis[3-allyl-4-(glycidyloxy)phenyl]propane; benzoxazine-containing aromatic allyl compounds such as bis[3-allyl-4-(3,4-dihydro-2H-1,3-benzoxazin-3-yl)phenyl]methane; ether-containing aromatic allyl compounds such as 1,3,5-triallyl ether benzene; and allyl silane compounds such as diallyldiphenylsilane. Commercially available allyl radical polymerizable resins include, for example, "TAIC" (1,3,5-triallyl isocyanurate) manufactured by Nippon Kasei Chemical Industry Co., Ltd., "DAD" (diallyl diphenate) manufactured by Nisshoku Techno Fine Chemical Co., Ltd., "TRIAM-705" (triallyl trimellitate) manufactured by Wako Pure Chemical Industries, Ltd., "DAND" (diallyl 2,3-naphthalenecarboxylate) manufactured by Nippon Distillation Industry Co., Ltd., and "ALP-d" (bis[3-allyl- Examples include "RE-810NM" (2,2-bis[3-allyl-4-(glycidyloxy)phenyl]propane) manufactured by Nippon Kayaku Co., Ltd., "DA-MGIC" (1,3-diallyl-5-glycidyl isocyanurate) manufactured by Shikoku Kasei Co., Ltd., and "NE-V-1100-70T" (a compound containing multiple allyl groups and multiple benzene rings) manufactured by DIC Corporation.

[0146] The ethylenically unsaturated bond equivalent of the (G) radically polymerizable resin is preferably 20 g / eq to 3,000 g / eq, more preferably 50 g / eq to 2,500 g / eq, even more preferably 70 g / eq to 2,000 g / eq, and particularly preferably 90 g / eq to 1,500 g / eq. The ethylenically unsaturated bond equivalent represents the mass of the radically polymerizable resin per equivalent of ethylenically unsaturated bonds.

[0147] The weight-average molecular weight (Mw) of the (G) radically polymerizable resin is preferably 40,000 or less, more preferably 10,000 or less, even more preferably 5,000 or less, and particularly preferably 3,000 or less. The lower limit is not particularly limited, but may be, for example, 150 or more. The weight-average molecular weight can be measured as a polystyrene-equivalent value by gel permeation chromatography (GPC).

[0148] The content of component (G) is preferably 1% by mass or more, more preferably 2% by mass or more, and even more preferably 3% by mass or more, and is preferably 7% by mass or less, more preferably 6% by mass or less, and even more preferably 5% by mass or less, assuming that the non-volatile components in the resin composition layer account for 100% by mass.

[0149] The content of the (G) component is preferably 1% by mass or more, more preferably 5% by mass or more, and even more preferably 10% by mass or more, and is preferably 20% by mass or less, more preferably 18% by mass or less, and even more preferably 15% by mass or less, assuming that the resin component in the resin composition layer is 100% by mass.

[0150] -(H) Radical polymerization initiator- The resin composition layer may contain a (H) radical polymerization initiator as the (H) component. The (H) radical polymerization initiator as the (H) component excludes those corresponding to the (B) to (G) components. The (G) radical polymerization initiator may be, for example, a thermal polymerization initiator that generates free radicals upon heating. The (H) radical polymerization initiator may also be a polymerization initiator of a radical reactive group. The (H) radical polymerization initiator may be used alone or in any combination of two or more.

[0151] (H) Examples of the radical polymerization initiator include peroxide radical polymerization initiators, azo radical polymerization initiators, etc. Among these, peroxide radical polymerization initiators are preferred.

[0152] Examples of the peroxide radical polymerization initiator include hydroperoxide compounds such as 1,1,3,3-tetramethylbutyl hydroperoxide; dialkyl peroxide compounds such as tert-butylcumyl peroxide, di-tert-butyl peroxide, di-tert-hexyl peroxide, dicumyl peroxide, 1,4-bis(1-tert-butylperoxy-1-methylethyl)benzene, and 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane; and diacyl peroxide compounds such as dilauroyl peroxide, didecanoyl peroxide, dicyclohexyl peroxydicarbonate, and bis(4-tert-butylcyclohexyl)peroxydicarbonate. peroxyester compounds such as tert-butyl peroxyacetate, tert-butyl peroxybenzoate, tert-butylperoxyisopropyl monocarbonate, tert-butylperoxy-2-ethylhexanoate, tert-butylperoxyneodecanoate, tert-hexylperoxyisopropyl monocarbonate, tert-butyl peroxylaurate, (1,1-dimethylpropyl) 2-ethylperhexanoate, tert-butyl 2-ethylperhexanoate, tert-butyl 3,5,5-trimethylperhexanoate, tert-butylperoxy-2-ethylhexyl monocarbonate, and tert-butylperoxymaleic acid; and the like.

[0153] Examples of the azo radical polymerization initiator include azonitrile compounds such as 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, 2,2'-azobis(2-methylbutyronitrile), 1,1'-azobis(cyclohexane-1-carbonitrile), 1-[(1-cyano-1-methylethyl)azo]formamide, and 2-phenylazo-4-methoxy-2,4-dimethyl-valeronitrile; 2,2'-azobis[2-methyl-N-[1,1-bis(hydroxymethyl)-2-hydroxyethyl]propionamide], and 2,2'-azobis[2-methyl-N-[1,1-bis(hydroxymethyl)-2-hydroxyethyl]propionamide]. azoamide compounds such as 2,2'-azobis[2-methyl-N-[2-(1-hydroxybutyl)]-propionamide], 2,2'-azobis[2-methyl-N-(2-hydroxyethyl)-propionamide], 2,2'-azobis(2-methylpropionamide) dihydrate, 2,2'-azobis[N-(2-propenyl)-2-methylpropionamide], 2,2'-azobis(N-butyl-2-methylpropionamide), and 2,2'-azobis(N-cyclohexyl-2-methylpropionamide); alkyl azo compounds such as 2,2'-azobis(2,4,4-trimethylpentane) and 2,2'-azobis(2-methylpropane); and the like.

[0154] (G) Commercially available radical polymerization initiators include, for example, "Perbutyl C," "Perbutyl A," "Perbutyl P," "Perbutyl L," "Perbutyl O," "Perbutyl ND," "Perbutyl Z," "Perbutyl I," "Percumyl P," "Percumyl D," "Perhexyl D," "Perhexyl A," "Perhexyl I," "Perhexyl Z," "Perhexyl ND," "Perhexyl O," and "Perhexyl PV," all manufactured by NOF Corporation.

[0155] The content of the (H) radical polymerization initiator is preferably 0.01% by mass or more, more preferably 0.03% by mass or more, and even more preferably 0.05% by mass or more, and is preferably 0.5% by mass or less, more preferably 0.3% by mass or less, and even more preferably 0.1% by mass or less, based on 100% by mass of the non-volatile components in the resin composition layer.

[0156] The content of the (H) radical polymerization initiator is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, and even more preferably 0.1% by mass or more, and is preferably 1% by mass or less, more preferably 0.5% by mass or less, and even more preferably 0.3% by mass or less, when the resin component in the resin composition layer is taken as 100% by mass.

[0157] -(I) Flame retardant- The resin composition layer may contain a flame retardant (I) as the component (I). The flame retardant (I) as the component (I) excludes those that fall under the components (B) to (H). The component (I) may be used alone or in combination of two or more.

[0158] (I) Examples of flame retardants include organic phosphorus flame retardants, organic nitrogen-containing phosphorus compounds, nitrogen compounds, silicone flame retardants, and metal hydroxides.

[0159] (I) As the flame retardant, a commercially available product may be used, for example, "HCA-HQ" manufactured by Sankosha.

[0160] The content of component (I) is preferably 0.1% by mass or more, more preferably 0.3% by mass or more, and even more preferably 0.5% by mass or more, and is preferably 5% by mass or less, more preferably 3% by mass or less, and even more preferably 1% by mass or less, assuming that the non-volatile components in the resin composition layer are 100% by mass.

[0161] The content of component (I) is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, and even more preferably 1% by mass or more, and is preferably 5% by mass or less, more preferably 4% by mass or less, and even more preferably 3% by mass or less, assuming that the resin component in the resin composition layer is 100% by mass.

[0162] -(J) Other additives- The resin composition layer may further contain other additives as optional components in addition to the components described above. (J) Other additives include, for example, organic fillers; organometallic compounds such as organocopper compounds, organozinc compounds, and organocobalt compounds; colorants such as phthalocyanine blue, phthalocyanine green, iodine green, diazo yellow, crystal violet, titanium oxide, and carbon black; polymerization inhibitors such as hydroquinone, catechol, pyrogallol, and phenothiazine; leveling agents such as silicone-based leveling agents and acrylic polymer-based leveling agents; thickeners such as bentone and montmorillonite; antifoaming agents such as silicone-based antifoaming agents, acrylic-based antifoaming agents, fluorine-based antifoaming agents, and vinyl resin-based antifoaming agents; ultraviolet absorbers such as benzotriazole-based ultraviolet absorbers; adhesion improvers such as urea silane; triazole-based adhesion promoters, tetrafluoroethylene copolymers, and the like. Examples of the (J) other additives include adhesion promoters such as triazole-based adhesion promoters and triazine-based adhesion promoters; antioxidants such as hindered phenol-based antioxidants; fluorescent brighteners such as stilbene derivatives; surfactants such as fluorine-based surfactants and silicone-based surfactants; dispersants such as phosphate ester-based dispersants, polyoxyalkylene-based dispersants, acetylene-based dispersants, silicone-based dispersants, anionic dispersants, and cationic dispersants; stabilizers such as borate-based stabilizers, titanate-based stabilizers, aluminate-based stabilizers, zirconate-based stabilizers, isocyanate-based stabilizers, carboxylic acid-based stabilizers, and carboxylic acid anhydride-based stabilizers; photopolymerization initiation aids such as tertiary amines; and photosensitizers such as pyrarizones, anthracenes, coumarins, xanthones, and thioxanthones. These (J) other additives may be used singly or in combination of two or more.

[0163] -(K) Solvent- In addition to the nonvolatile components described above, the resin composition layer may further contain an arbitrary solvent as a volatile component. As the (K) solvent, any known solvent can be used appropriately, and the type is not particularly limited, but an organic solvent is preferred. Examples of the (K) solvent include ketone-based solvents such as acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone, and cyclohexanone; ester-based solvents such as methyl acetate, ethyl acetate, butyl acetate, isobutyl acetate, isoamyl acetate, methyl propionate, ethyl propionate, and γ-butyrolactone; ether-based solvents such as tetrahydropyran, tetrahydrofuran, 1,4-dioxane, diethyl ether, diisopropyl ether, dibutyl ether, diphenyl ether, and anisole; alcohol-based solvents such as methanol, ethanol, propanol, butanol, and ethylene glycol; 2-ethoxyethyl acetate, propylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, ethyl diglycol acetate, γ-butyrolactone, and methyl methoxypropionate. Examples of suitable solvents include ether ester solvents such as methyl lactate, ethyl lactate, and methyl 2-hydroxyisobutyrate; ether alcohol solvents such as 2-methoxypropanol, 2-methoxyethanol, 2-ethoxyethanol, propylene glycol monomethyl ether, and diethylene glycol monobutyl ether (butyl carbitol); amide solvents such as N,N-dimethylformamide, N,N-dimethylacetamide, and N-methyl-2-pyrrolidone; sulfoxide solvents such as dimethyl sulfoxide; nitrile solvents such as acetonitrile and propionitrile; aliphatic hydrocarbon solvents such as hexane, cyclopentane, cyclohexane, and methylcyclohexane; aromatic hydrocarbon solvents such as benzene, toluene, xylene, ethylbenzene, and trimethylbenzene; and solvent naphtha. The (K) solvent may be used alone or in combination of two or more solvents in any ratio.

[0164] Usually, all or most of the (K) solvent is removed by drying during the production process of the resin composition layer. Therefore, the resin composition layer may not contain the (K) solvent. Furthermore, when the resin composition layer contains the (K) solvent, voids may occur due to the solvent volatilizing during the thermal curing in step (II). Therefore, from the viewpoint of suppressing the occurrence of voids, when the resin composition layer is formed using a resin varnish, it is preferable to perform sufficient drying during the production process of the resin composition layer to reduce the amount of the (K) solvent remaining in the resin composition layer.

[0165] The thickness of the resin composition layer is preferably 500 μm or less, more preferably 300 μm or less, and even more preferably 250 μm or less, from the viewpoint of reducing the thickness of the printed wiring board and providing a cured product with excellent insulating properties even when the cured product of the resin composition layer is thin. The lower limit of the thickness of the resin composition layer is not particularly limited, but may be, for example, 1 μm or more, 3 μm or more, 5 μm or more, etc.

[0166] <Other layers> The resin sheet may further have a protective film conforming to the support laminated on the surface of the resin composition layer not bonded to the support, i.e., the surface opposite to the support. The thickness of the protective film is not particularly limited, but is, for example, 1 μm to 40 μm. By laminating the protective film, adhesion of dust and the like to the surface of the resin composition layer and scratches can be suppressed.

[0167] <Method of manufacturing resin sheet> The resin sheet can be produced, for example, by a method including forming a resin composition layer on a support. Specifically, the resin sheet may be produced by a production method including, in this order, a step of preparing a resin varnish containing the resin composition, a step of applying the resin varnish to a support, and a step of drying the applied resin varnish to form a resin composition layer.

[0168] The resin varnish may be produced by mixing the components that can be contained in the resin composition layer and a solvent. The solvent (K) described above may be used as the solvent for the resin varnish. The components may be mixed partially or entirely at the same time, or may be mixed sequentially. In the process of mixing the components, the temperature may be appropriately set, and thus heating and / or cooling may be performed temporarily or throughout. Furthermore, stirring or shaking may be performed in the process of mixing the components.

[0169] The resin varnish can be applied using a coating device such as a die coater. Drying can be performed by known methods such as heating or hot air blowing. The drying conditions are not particularly limited, but drying is performed so that the solvent content in the resin composition layer becomes 10% by mass or less, preferably 5% by mass or less. Although this varies depending on the boiling point of the solvent in the resin varnish, for example, when a resin varnish containing 30% by mass to 60% by mass of solvent is used, the resin composition layer can be formed by drying at 50°C to 150°C for 3 to 10 minutes.

[0170] The resin sheet can be stored in a rolled state. When the resin sheet has a protective film, it can be used by peeling off the protective film.

[0171] [Method of manufacturing semiconductor chip packages] The method for manufacturing a semiconductor chip package of the present invention comprises: (I) a step of laminating a resin composition layer of a resin sheet having a support and a resin composition layer provided on the support on a semiconductor chip package in which at least one semiconductor chip is mounted on a circuit board, and performing mold underfill; and (II) a step of thermally curing the resin composition layer; Contains, in this order:

[0172] In the present invention, the mold underfill is performed using a resin composition layer having a loss tangent of 0.05 or more and 1.3 or less at molding temperatures. Therefore, even in semiconductor chip packages having multiple semiconductor chips or large semiconductor chip packages, external pressure in the mold underfill is efficiently applied to the resin composition layer, and the resin composition layer fills gaps and spaces between electrodes even if the gaps or spaces between electrodes are narrow. This makes it possible to suppress the generation of voids in the gaps and spaces between electrodes.

[0173] <Process (I)> In step (I), a resin sheet comprising a support and a resin composition layer provided on the support is laminated on a semiconductor chip package having at least one semiconductor chip mounted on a circuit board so that the resin composition layer is bonded to the semiconductor chip package, and mold underfill is performed.

[0174] Step (I) is (I-1) preparing a resin sheet; (I-2) preparing a semiconductor chip package in which at least one semiconductor chip is mounted on a circuit board; and (I-3) a step of laminating a resin composition layer of a resin sheet on a semiconductor chip package; Typically, in the lamination in step (I-3), the resin composition layer is pressed onto the semiconductor chip package at a molding temperature to achieve mold underfill. Furthermore, the step (I) may optionally include, as an optional step after the step (I-3), (I-4) a step of pressing the resin composition layer to smooth it; may also include:

[0175] The resin sheet prepared in step (I-1) is as described above in the section [Resin Sheet]. When the resin sheet has a protective film, the protective film is peeled off to expose the resin composition layer.

[0176] In the present invention, a resin composition layer is used whose loss tangent at the temperature at which the mold underfill is performed (molding temperature), i.e., the temperature at which step (I-3) is performed, is 0.05 or more and 1.3 or less. Therefore, even in semiconductor chip packages having multiple semiconductor chips or large semiconductor chip packages, external pressure from the mold underfill is efficiently applied to the resin composition layer, and the resin composition layer fills the gaps and spaces between electrodes even if the gaps and spaces between electrodes are narrow. This makes it possible to suppress the generation of voids in the gaps and spaces between electrodes.

[0177] In step (I-2), at least one semiconductor chip is bonded and mounted on a circuit board to obtain a semiconductor chip package. The circuit board may be a conventionally known circuit board used for forming semiconductor chip packages. The circuit board may have either a conductor layer or an insulating layer on one or both sides, and either the conductor layer or the insulating layer may be patterned.

[0178] The circuit board and the semiconductor chip can be joined by, for example, forming bumps on the circuit board or the semiconductor chip, which may be performed according to a method known to those skilled in the art and used in the manufacture of semiconductor chip packages.

[0179] The bonding conditions for the circuit board and the semiconductor chip may be any conditions that allow conductive connection between the terminal electrodes of the semiconductor chip and the circuit wiring of the circuit board, such as the conditions used in flip-chip mounting of semiconductor chips.

[0180] An example of a bonding method is a method in which a semiconductor chip is pressure-bonded to a circuit board. Pressure-bonding conditions include a pressure-bonding temperature typically in the range of 120°C to 240°C (preferably in the range of 130°C to 200°C, and more preferably in the range of 140°C to 180°C), and a pressure-bonding time typically in the range of 1 second to 60 seconds (preferably in the range of 5 seconds to 30 seconds). Another example of a bonding method is a method in which a semiconductor chip is placed on a circuit board and bonded by reflow. Reflow conditions may be in the range of 120°C to 300°C.

[0181] The number of semiconductor chips bonded to the circuit board needs to be at least one. In the present invention, the mold underfill is performed using a resin composition layer having a loss tangent of 0.05 or more and 1.3 or less, so that the number of semiconductor chips may be multiple, and even if the semiconductor chip package has a large area, the resin composition layer can fill the gap. The specific number of semiconductor chips varies depending on the semiconductor device equipped with the semiconductor chip package, but is, for example, preferably 2 or more, more preferably 5 or more, even more preferably 10 or more, and preferably 500 or less, more preferably 400 or less, and even more preferably 300 or less.

[0182] In the present invention, a resin composition layer having a loss tangent of 0.05 or more and 1.3 or less at the temperature at which step (I-3) is performed is used. Therefore, even if the gap between the circuit board and the semiconductor chip is narrow, the resin composition layer can fill the gap. The gap is preferably 60 μm or less, more preferably 50 μm or less, and even more preferably 40 μm or less. The lower limit is not particularly limited, but can be 1 μm or more.

[0183] In step (I-3), the resin composition layer of the resin sheet is laminated on the semiconductor chip package. Typically, the resin composition layer and the semiconductor chip package are laminated by pressure bonding at a molding temperature so that the resin composition layer and the semiconductor chip package are bonded. This lamination fills the gap between the semiconductor chip and the circuit board with the resin composition layer, achieving mold underfill.

[0184] In the first embodiment, step (I-3) may be performed by laminating the resin composition layer so as to bond it to the semiconductor chip package to perform mold underfilling, or in the second embodiment, step (I-3) may be performed using a heat press.

[0185] -First embodiment- In step (I-3) according to the first embodiment, the semiconductor chip package and the resin composition layer of the resin sheet are laminated so as to be in contact with each other. The laminated resin composition layer and the semiconductor chip package are then heated and pressed together, so that the gap between the circuit board and the semiconductor chip can be filled and the semiconductor chip can be sealed at the same time.

[0186] In the first embodiment, the semiconductor chip package and the resin composition layer of the resin sheet can be laminated by thermocompression bonding the resin sheet to the inner layer substrate from the support side. Examples of a member for thermocompression bonding the resin sheet to the semiconductor chip package (hereinafter also referred to as a "thermocompression bonding member") include a heated metal plate (such as a SUS end plate) or a metal roll (SUS roll). It is preferable to press the thermocompression bonding member not directly onto the resin sheet, but via an elastic material such as heat-resistant rubber, so that the resin sheet can adequately conform to the surface irregularities of the semiconductor chip package.

[0187] The lamination can be performed using a commercially available vacuum laminator, such as a vacuum pressure laminator manufactured by Meiki Seisakusho Co., Ltd., a vacuum applicator manufactured by Nikko Materials Co., Ltd., or a batch-type vacuum pressure laminator.

[0188] The thermocompression bonding temperature, i.e., the molding temperature, is preferably set under conditions such that the loss tangent of the resin composition layer is 0.05 or more and 1.3 or less. The thermocompression bonding temperature varies depending on the composition of the resin composition layer, but is, for example, preferably 70°C or more, more preferably 80°C or more, even more preferably 90°C or more, 100°C or more, 110°C or more, 120°C or more, or 130°C or more, and is preferably 180°C or less, more preferably 170°C or less, even more preferably 160°C or less, 150°C or less, or 140°C or less.

[0189] The thermocompression pressure is preferably in the range of 0.098 MPa to 1.77 MPa, more preferably 0.29 MPa to 1.47 MPa.

[0190] The thermocompression time is preferably in the range of 20 seconds to 400 seconds, more preferably 30 seconds to 300 seconds. In the first embodiment, the step (I-3) is preferably carried out under reduced pressure conditions of 26.7 hPa or less.

[0191] After lamination, the laminated resin sheets may be smoothed under normal pressure (atmospheric pressure), for example, by performing step (I-4) of pressing the support side with a thermocompression member. The pressing conditions for the smoothing treatment may be the same as the thermocompression conditions for lamination. The smoothing treatment may be performed using a commercially available laminator. Note that lamination and smoothing treatment may be performed consecutively using the commercially available vacuum laminator.

[0192] The support may be peeled off between step (I) and step (II) or after step (II).

[0193] -Second embodiment- In the second embodiment, in step (I-3), the semiconductor chip package and the resin sheet are laminated using a heat press. Typically, the resin composition layer and the semiconductor chip package are laminated by pressing them at a molding temperature so that they are bonded to each other in a mold.

[0194] In the second embodiment, the details of step (I-3) may be, for example, to place a semiconductor chip package on the lower mold of a mold for heat pressing, place a resin sheet on the surface of the semiconductor chip package, and then clamp the mold to laminate the semiconductor chips. Alternatively, for example, a resin sheet may be placed on the lower mold of a mold for heat pressing, and attach a semiconductor chip package to the upper mold, and then clamp the mold to laminate the semiconductor chips. In either case, clamping the mold heats and presses the resin composition layer and the semiconductor chip package in the mold, so that the resin composition layer can fill the gap between the circuit board and the semiconductor chip and seal the semiconductor chip all at once.

[0195] The mold underfill in the second embodiment is usually performed by heat pressing. Specific procedures for the mold underfill are, for example, as follows: Heatable upper and lower molds are prepared as molds for heat pressing. In step (I-3), a laminate of a resin composition layer and a semiconductor chip package is placed on the lower mold, and the upper and lower molds are heat pressed while being heated, filling the gap with the resin composition layer and simultaneously sealing the semiconductor chips.

[0196] When the mold underfill is formed by heat pressing, the temperature of the mold during heat pressing, i.e., the molding temperature, varies depending on the composition of the resin composition layer, but is, for example, preferably 70°C or higher, more preferably 80°C or higher, even more preferably 90°C or higher, 100°C or higher, 110°C or higher, 120°C or higher, or 130°C or higher, and is preferably 180°C or lower, more preferably 170°C or lower, even more preferably 160°C or lower, 150°C or lower, or 140°C or lower.

[0197] Furthermore, the pressure applied during the heat pressing is preferably 1 MPa or more, more preferably 3 MPa or more, and particularly preferably 5 MPa or more, from the viewpoint of filling the gap with the resin composition layer and simultaneously sealing the semiconductor chip, and is preferably 50 MPa or less, more preferably 30 MPa or less, and particularly preferably 20 MPa or less.

[0198] From the viewpoint of improving the adhesion of the resin composition layer to the semiconductor chip package, the heat pressing is preferably carried out under reduced pressure conditions, preferably a pressure of 5 to 10 Torr and a reduced pressure holding time (the time from the start of pressure reduction to the start of heat pressing) of 5 to 600 seconds.

[0199] After the gap is filled and the semiconductor chip is sealed, the upper mold and the upper mold are removed. The mold may be removed after step (I) or after step (II). The support may be peeled off between steps (I) and (II) or after step (II).

[0200] <Process (II)> In step (II), the resin composition layer filled in the gap and the resin composition layer formed on the semiconductor chip are thermally cured to fill the gap with the cured resin composition layer and form an encapsulating layer on the semiconductor chip package.

[0201] The method for thermally curing the resin composition layer in step (II) includes a two-step heating method and a one-step heating method. The two-step heating method is a method in which the resin composition layer is subjected to a heat treatment at a temperature T1, and then subjected to a heat treatment at a temperature T2 higher than T1. Hereinafter, the heat treatment at temperature T1 will also be referred to as a "pre-cure step," and the heat treatment at temperature T2 will also be referred to as a "post-cure step."

[0202] The one-stage heating method is a method in which the resin composition layer is subjected to a heat treatment in which it is not held at temperature T1 but is held at temperature T2, that is, a method in which only a post-cure step is carried out without a pre-cure step.

[0203] By carrying out the pre-cure step, it is possible to suppress the occurrence of voids that occur when the solvent contained in the resin composition layer evaporates. Therefore, in step (II), it is preferable to perform thermal curing by a two-stage heating method. The units of temperatures T1 and T2 are "°C", and T1 <T2である。

[0204] -Pre-cure process (heat treatment held at temperature T1)- Typically, before the precure step, the resin composition layer is at a temperature-rise start temperature T0 (°C), which is lower than temperature T1. Temperature-rise start temperature T0 can be, for example, room temperature. Therefore, step (II) can include a step of raising the temperature of the resin composition layer from temperature-rise start temperature T0 to temperature T1 before the precure step. From the viewpoint of significantly achieving the effects of the present invention, the temperature-rise rate in this temperature-rise step is preferably 0.5°C / min or more, more preferably 1°C / min or more, even more preferably 1.5°C / min or more, even more preferably 2°C / min or more, and particularly preferably 2.5°C / min or more. The upper limit is preferably 30°C / min or less, more preferably 25°C / min or less, even more preferably 20°C / min or less, even more preferably 15°C / min or less, and particularly preferably 10°C / min or less. The temperature-rise rate in the temperature-rise step may be constant or variable.

[0205] In the precure step, the resin composition layer is subjected to a heat treatment in which the resin composition layer is maintained at a temperature T1. The heating temperature T1 in this precure step is set within a temperature range higher than room temperature and lower than a temperature T2. To significantly achieve the effects of the present invention, the specific range of the heating temperature T1 is preferably 50°C or higher, more preferably 60°C or higher, even more preferably 70°C or higher, and even more preferably 80°C or higher. The upper limit is preferably less than 150°C, more preferably 140°C or lower, and even more preferably 130°C or lower. In the precure step, maintaining the resin composition layer at a temperature T1 does not necessarily mean maintaining the temperature of the resin composition layer at a constant temperature, but also includes fluctuating the temperature of the resin composition layer within a range that does not significantly impair the effects of the present invention. For example, the temperature of the resin composition layer in the precure step may fluctuate within a range of ±10°C, ±8°C, or ±5°C. However, even when the temperature of the resin composition layer fluctuates in this manner, the temperature of the resin composition layer in the pre-cure step is preferably within the above-mentioned preferred range, for example, within a range of 50° C. or higher and lower than 150° C. In particular, it is particularly preferable that the temperature of the resin composition layer does not fluctuate and is constant in the pre-cure step.

[0206] The time for which the resin composition layer is held at the heating temperature T1 in the pre-cure process depends on the composition of the resin composition layer and the value of the heating temperature T1, but from the viewpoint of significantly obtaining the effects of the present invention, it is preferably 10 minutes or more, more preferably 15 minutes or more, and even more preferably 20 minutes or more, and the upper limit is preferably 150 minutes or less, more preferably 120 minutes or less, and even more preferably 120 minutes or less.

[0207] -Post-cure process (heat treatment held at temperature T2)- Typically, before the post-cure step, the resin composition layer is at a temperature lower than temperature T2. Therefore, step (II) may include a step of raising the temperature of the resin composition layer to temperature T2 after the pre-cure step and before the post-cure step. From the viewpoint of significantly achieving the effects of the present invention, the temperature rise rate in this temperature rise step is preferably 0.5°C / min or more, more preferably 1°C / min or more, even more preferably 1.5°C / min or more, even more preferably 2°C / min or more, and particularly preferably 2.5°C / min or more, and the upper limit is preferably 30°C / min or less, more preferably 25°C / min or less, even more preferably 20°C / min or less, even more preferably 15°C / min or less, and particularly preferably 10°C / min or less. Therefore, in one embodiment, in step (II), the resin composition layer is raised to temperature T2 at a temperature rise rate of 0.5°C / min or more and 30°C / min or less. The temperature rise rate in the temperature rise step may be constant or may be varied.

[0208] In the post-cure step, the resin composition layer is subjected to a heat treatment at a temperature T2. The heating temperature T2 in the post-cure step is set to a temperature higher than the temperature T1. To significantly achieve the effects of the present invention, the specific range of the heating temperature T2 is preferably 150°C or higher, more preferably 155°C or higher, even more preferably 160°C or higher, and particularly preferably 170°C or higher. The upper limit is preferably 250°C or lower, more preferably 230°C or lower, even more preferably 220°C or lower, even more preferably 210°C or lower, and particularly preferably 200°C or lower. In the post-cure step, maintaining the resin composition layer at a temperature T2 not only means maintaining the temperature of the resin composition layer at a constant temperature, but also includes fluctuating the temperature of the resin composition layer within a range that does not significantly impair the effects of the present invention. For example, the temperature of the resin composition layer in the post-cure step may fluctuate within a range of ±10°C, ±8°C, or ±5°C. However, even when the temperature of the resin composition layer fluctuates in this manner, the temperature of the resin composition layer in the post-cure step is preferably within the above-mentioned preferred range, for example, within the range of 150° C. to 250° C. In particular, it is particularly preferable that the temperature of the resin composition layer does not fluctuate and is constant in the post-cure step.

[0209] The difference T2-T1 between the heating temperature T1 in the precure step and the heating temperature T2 in the postcure step is preferably within a specific range from the viewpoint of significantly achieving the effects of the present invention. Specifically, the difference T2-T1 is preferably 20°C or more, more preferably 30°C or more, and even more preferably 40°C or more, with the upper limit being preferably 150°C or less, more preferably 140°C or less, even more preferably 130°C or less, and particularly preferably 120°C or less. When the temperature of the resin composition layer fluctuates in the precure step and / or the postcure step, it is preferable that the difference between the median temperature of the resin composition in the precure step and the median temperature of the resin composition in the postcure step be within the above range.

[0210] The time for which the resin composition layer is held at the heating temperature T2 in the post-cure process depends on the composition of the resin composition layer and the value of the heating temperature T2, but from the viewpoint of significantly obtaining the effects of the present invention, it is preferably 10 minutes or more, more preferably 15 minutes or more, and even more preferably 20 minutes or more, and the upper limit is preferably 150 minutes or less, more preferably 120 minutes or less.

[0211] After the heat treatment at temperature T1 in the precure step, the resin composition layer may be cooled and then subjected to a heat treatment at heating temperature T2 in the postcure step. Alternatively, after the heat treatment at temperature T1 in the precure step, the resin composition layer may be subjected to a heat treatment at temperature T2 in the postcure step without being cooled.

[0212] The heat treatment in the precure step and the heat treatment in the postcure step may be performed using the same heat treatment device. Alternatively, the heat treatment in the precure step may be performed using a first heat treatment device, and the heat treatment in the postcure step may be performed using a second heat treatment device different from the first heat treatment device. The heat treatment device is not particularly limited as long as it can thermally cure the resin composition layer. Examples of heat treatment devices that can be used include an oven and a hot press. For example, the heat treatment in the precure step may be performed using an oven adjusted to temperature T1, and then the laminate of the substrate and the resin sheet may be transferred to an oven adjusted to temperature T2, and the heat treatment in the postcure step may be performed. Alternatively, the heat treatment in the precure step may be performed using a temperature-programmable heat treatment device, and then the temperature may be increased from temperature T1 to temperature T2, and the heat treatment in the postcure step may be performed.

[0213] Step (II) may include any additional steps in addition to the pre-cure step, post-cure step, and the temperature-raising step before those steps. For example, step (II) may include a step of subjecting the resin composition layer to a heat treatment in which the resin composition layer is maintained at a temperature other than temperatures T1 and T2. That is, step (II) is not limited to a one-step or two-step heat treatment, but may include three or more steps of heat treatment.

[0214] Step (II) is preferably carried out in a nitrogen atmosphere. When the nitrogen atmosphere contains oxygen, the oxygen concentration in the nitrogen atmosphere is preferably 5% by mass or less, more preferably 3% by mass or less, and even more preferably 1% by mass or less, and may be 0% by mass.

[0215] The pressure condition of the nitrogen atmosphere in which step (II) is carried out may be normal pressure or reduced pressure. In one example, the specific pressure condition of the nitrogen atmosphere is preferably 0.1 hPa or more, more preferably 1.3 hPa or more, and the upper limit thereof is preferably 5000 hPa or less, more preferably 2500 hPa or less.

[0216] The production method of the present invention may include other steps as long as it includes the above steps (I) and (II) in that order.

[0217] The semiconductor chip package manufactured by the manufacturing method of the present invention may be either a fan-in type package or a fan-out type package. When the semiconductor package is a fan-out type package, the rewiring layer can be formed over a large area, which is an inherent feature of the fan-out type package, and a conductor circuit can be formed over a large area with a fine pattern.

[0218] The semiconductor chip package manufactured by the manufacturing method of the present invention contains a cured resin composition layer having a loss tangent of 0.05 to 1.3 at the temperature where the mold underfill is performed, and therefore exhibits the characteristic of a low dielectric loss tangent. A 40 μm-thick resin composition layer is thermally cured at 130°C for 30 minutes and then at 200°C for 90 minutes to obtain a cured product for evaluation. The cured product for evaluation is cut to a predetermined size, and the dielectric loss tangent is measured three times using the cavity resonance perturbation method at a measurement frequency of 5.8 GHz and a measurement temperature of 23°C. The average value of the dielectric loss tangent is preferably 0.01 or less, more preferably 0.008 or less, and even more preferably 0.005 or less. The lower limit is not particularly limited, but can be 0.0001 or more. The dielectric loss tangent can be measured using the method described in the Examples below.

[0219] The semiconductor chip package manufactured by the manufacturing method of the present invention uses a resin composition layer having a loss tangent of 0.05 to 1.3 at the temperature at which mold underfilling is performed. Therefore, even before the resin composition layer is laminated on the semiconductor chip package and cured, it exhibits the characteristic of suppressing the generation of voids. For example, a resin composition layer is laminated on a glass substrate with 12 semiconductor chips (4 vertical and 3 horizontal), connected with gold bumps so that the chip-to-chip distance is 400 μm and the gap between the glass substrate and the semiconductor chip is 30 μm, to obtain an evaluation substrate. When the number of semiconductor chips in this evaluation substrate that have voids in the resin composition between the semiconductor chip and the glass substrate is counted, the number of voids is preferably 2 or less, and more preferably, no voids are present. Voids can be evaluated using the method described in the Examples below.

[0220] The semiconductor chip package manufactured by the manufacturing method of the present invention uses a resin composition layer with a loss tangent of 0.05 to 1.3 at the temperature at which mold underfilling is performed. Therefore, even after laminating the resin composition layer on the semiconductor chip package and thermally curing the resin composition layer, the generation of voids is suppressed. For example, a resin composition layer is laminated onto a glass substrate, for a total of 12 semiconductor chips (4 vertical and 3 horizontal), with a chip-to-chip distance of 400 μm and a gap of 30 μm between the glass substrate and the semiconductor chips, connected with gold bumps. The resin composition layer is then thermally cured to obtain an evaluation substrate. When the number of semiconductor chips in this evaluation substrate that have voids in the resin composition between the semiconductor chip and the glass substrate is counted, the number of voids is preferably 3 or less, more preferably 2 or less, and even more preferably no voids are present. Voids can be evaluated using the method described in the Examples below. [Example]

[0221] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. In the following description, "parts" means "parts by mass" unless otherwise specified. Unless otherwise specified, the measurements were carried out at room temperature and atmospheric pressure.

[0222] [Synthesis of Elastomer A] A reaction vessel was charged with 69 g of bifunctional hydroxy-terminated polybutadiene ("G-3000" manufactured by Nippon Soda Co., Ltd., number average molecular weight = 3000, hydroxy group equivalent weight = 1800 g / eq.), 40 g of an aromatic hydrocarbon mixed solvent ("IPZOL 150" manufactured by Idemitsu Petrochemical Co., Ltd.), and 0.005 g of dibutyltin laurate, which were mixed and dissolved uniformly. Once homogeneous, the mixture was heated to 60°C, and 8 g of isophorone diisocyanate ("IPDI" manufactured by Evonik Degussa Japan Co., Ltd., isocyanate group equivalent weight = 113 g / eq.) was added with further stirring, and the reaction was carried out for approximately 3 hours.

[0223] Next, 23 g of cresol novolak resin (DIC Corporation "KA-1160", hydroxyl group equivalent = 117 g / eq.) and 60 g of ethyl diglycol acetate (Daicel Corporation) were added to the reaction mixture, and the mixture was heated to 150 °C with stirring and reacted for about 10 hours. -1 The disappearance of the NCO peak was confirmed. The disappearance of the NCO peak was considered to be the end of the reaction, and the reaction mixture was cooled to room temperature. The reaction mixture was then filtered through a 100-mesh filter cloth to obtain an elastomer having a butadiene structure and phenolic hydroxyl groups (phenolic hydroxyl group-containing butadiene resin: non-volatile components 50% by mass). The number-average molecular weight of elastomer A was 5,900, and the glass transition temperature was -7°C.

[0224] [Inorganic filler used] Inorganic filler A: average particle size 3μm, specific surface area 3.5m 2 / g, surface treated with KBM573 (Shin-Etsu Chemical Co., Ltd.). Inorganic filler B: average particle size 0.5μm, specific surface area 5.9m 2 / g, surface treated with KBM573 (Shin-Etsu Chemical Co., Ltd.).

[0225] [Examples 1 and 2, Comparative Example 1] 30 parts of bixylenol-type epoxy resin ("YX4000HK" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent weight: approximately 185 g / eq.), 20 parts of biphenyl-type epoxy resin ("NC3000L" manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent weight: approximately 272 g / eq.), and 10 parts of naphthylene ether-type epoxy resin ("HP-6000L" manufactured by DIC Corporation, epoxy equivalent weight: 215 g / eq.) were heated and dissolved with stirring in a mixed solvent of 20 parts solvent naphtha and 30 parts cyclohexanone. The mixture was cooled to room temperature to prepare a dissolved epoxy resin composition. This epoxy resin solution composition was mixed with 30 parts of Elastomer A, 20 parts of a phenolic curing agent having a triazine skeleton and a novolac structure (DIC Corporation's "LA3018-50P," reactive group equivalent weight approximately 151 g / eq., non-volatile content 50% in 2-methoxypropanol solution), and 20 parts of an active ester curing agent (DIC Corporation's "HPC-8000-65T," reactive group equivalent weight approximately 223 g / eq., non-volatile content 65% in toluene). A resin varnish was prepared by mixing 50 parts of a carbodiimide curing agent ("V-03" manufactured by Nisshinbo Chemical Inc., carbodiimide group equivalent weight 216 g / eq., toluene solution with a nonvolatile content of 50% by mass), 1 part of a curing accelerator (1-benzyl-2-phenylimidazole (1B2PZ), MEK solution with a nonvolatile content of 10% by mass), 10 parts of a curing accelerator (4-dimethylaminopyridine (DMAP), MEK solution with a solid content of 2.5% by mass), and 650 parts of inorganic filler A, and dispersing the mixture uniformly using a high-speed rotating mixer.

[0226] A polyethylene terephthalate film ("AL5" manufactured by Lintec Corporation, thickness 38 μm) with a release layer was prepared as a support. The resin varnish was uniformly applied onto the release layer of this support so that the thickness of the resin composition layer after drying would be 200 μm. The resin varnish was then dried at 80°C to 120°C (average 100°C) for 6 minutes to prepare a resin sheet including a support and a resin composition layer (thickness 200 μm). Another resin sheet including a support and a resin composition layer (thickness 40 μm) was prepared using the same method, except that the thickness of the resin composition layer after drying was 40 μm.

[0227] [Examples 3 to 4, Comparative Example 2] Bisphenol A epoxy resin (Nippon Steel & Sumikin Chemical Co., Ltd. "YD-8125G", epoxy equivalent: approx. 174 g / eq.) 2 parts, bixylenol epoxy resin (Mitsubishi Chemical Co., Ltd. "YX4000HK", epoxy equivalent: approx. 185 g / eq.) 5 parts, naphthylene ether epoxy resin (DIC Corporation "EXA-7311-G4", epoxy equivalent: approx. 213 g / eq.) 5 parts, biphenyl epoxy resin (Nippon Kayaku Co., Ltd. "NC30 15 parts of epoxidized polybutadiene ("PB3600" manufactured by Daicel Corporation, epoxy equivalent of approximately 272 g / eq.), 2 parts of epoxidized polybutadiene ("PB3600" manufactured by Daicel Corporation, epoxy equivalent of approximately 193 g / eq.), and 10 parts of phenoxy resin ("YX7553BH30" manufactured by Mitsubishi Chemical Corporation, a 1:1 solution of cyclohexanone and methyl ethyl ketone (MEK) with a solids content of 30 mass %) were heated and dissolved with stirring in a mixed solvent of 15 parts solvent naphtha and 10 parts cyclohexanone. After cooling to room temperature, 5 parts of a triazine skeleton-containing cresol novolac curing agent (DIC Corporation's "LA3018-50P," hydroxyl group equivalent weight approximately 151 g / eq., 2-methoxypropanol solution with a solid content of 50%), 12 parts of an active ester curing agent (DIC Corporation's "HPC-8000-65T," active group equivalent weight approximately 223 g / eq., toluene solution with a non-volatile content of 65% by mass), 12 parts of a carbodiimide resin (Nisshinbo Chemical Inc.'s " A resin varnish was prepared by mixing 10 parts of "V-03," carbodiimide equivalent 216 g / eq., toluene solution with 50% nonvolatile content, 3 parts of curing accelerator (4-dimethylaminopyridine (DMAP), MEK solution with 2.5% solids content), 2 parts of flame retardant (Sankosha's "HCA-HQ," 10-(2,5-dihydroxyphenyl)-10-hydro-9-oxa-10-phosphaphenanthrene-10-oxide, average particle size 1.2 μm), and 180 parts of inorganic filler B, and dispersing the mixture uniformly using a high-speed rotary mixer.

[0228] A polyethylene terephthalate film ("AL5" manufactured by Lintec Corporation, thickness 38 μm) with a release layer was prepared as a support. The resin varnish was uniformly applied onto the release layer of this support so that the thickness of the resin composition layer after drying would be 200 μm. The resin varnish was then dried at 80°C to 120°C (average 100°C) for 6 minutes to produce a resin sheet including a support and a resin composition layer. In addition, a resin sheet including a support and a resin composition layer (thickness 40 μm) was produced using the same method, except that the thickness of the resin composition layer after drying was 40 μm.

[0229] [Example 5] 30 parts of bixylenol-type epoxy resin ("YX4000HK" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent weight: approximately 185 g / eq.), 20 parts of biphenyl-type epoxy resin ("NC3000L" manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent weight: approximately 272 g / eq.), and 10 parts of naphthylene ether-type epoxy resin ("HP-6000L" manufactured by DIC Corporation, epoxy equivalent weight: 215 g / eq.) were heated and dissolved with stirring in a mixed solvent of 20 parts solvent naphtha and 30 parts cyclohexanone. The mixture was cooled to room temperature to prepare a dissolved epoxy resin composition. This epoxy resin solution composition was mixed with 30 parts of elastomer A, 20 parts of a phenolic curing agent having a triazine skeleton and a novolak structure (DIC Corporation's "LA3018-50P," reactive group equivalent weight approximately 151 g / eq., 2-methoxypropanol solution with a nonvolatile content of 50%), 10 parts of a carbodiimide curing agent (Nisshinbo Chemical Inc.'s "V-03," carbodiimide group equivalent weight 216 g / eq., toluene solution with a nonvolatile content of 50% by mass), 1 part of a curing accelerator (1-benzyl-2-phenylimidazole (1B2PZ), MEK solution with a nonvolatile content of 10% by mass), 10 parts of a curing accelerator (4-dimethylaminopyridine (DMAP), MEK solution with a solid content of 2.5% by mass), and 610 parts of inorganic filler A. The mixture was uniformly dispersed using a high-speed rotary mixer to produce resin varnish 3.

[0230] A polyethylene terephthalate film ("AL5" manufactured by Lintec Corporation, thickness 38 μm) with a release layer was prepared as a support. The resin varnish was uniformly applied onto the release layer of this support so that the thickness of the resin composition layer after drying would be 200 μm. The resin varnish was then dried at 80°C to 120°C (average 100°C) for 6 minutes to produce a resin sheet including a support and a resin composition layer. In addition, a resin sheet including a support and a resin composition layer (thickness 40 μm) was produced using the same method, except that the thickness of the resin composition layer after drying was 40 μm.

[0231] [Examples 6 to 7, Comparative Example 3] Ten parts of a bisphenol-type epoxy resin ("ZX1059" manufactured by Nippon Steel & Sumitomo Metal Chemical Co., Ltd., a 1:1 mixture of bisphenol A and bisphenol F, epoxy equivalent weight 169 g / eq.) and 50 parts of a naphthol-type epoxy resin ("ESN475V" manufactured by Nippon Steel & Sumitomo Metal Chemical Co., Ltd., epoxy equivalent weight approximately 330 g / eq.) were heated and dissolved in 40 parts of solvent naphtha with stirring. The mixture was cooled to room temperature to prepare a dissolved epoxy resin composition. This epoxy resin solution composition was mixed with 5 parts of a phenoxy resin ("YX7553BH30" manufactured by Mitsubishi Chemical Corporation, a 1:1 solution of MEK and cyclohexanone with a non-volatile content of 30% by mass), 5 parts of a phenolic curing agent having a triazine skeleton and a novolac structure ("LA3018-50P" manufactured by DIC Corporation, a reactive group equivalent of approximately 151 g / eq., a 2-methoxypropanol solution with a non-volatile content of 50%), and 5 parts of an active ester curing agent ("HPC-8000-65T" manufactured by DIC Corporation, a reactive group equivalent of approximately 223 g / eq., a toluene solution with a non-volatile content of 65% by mass). A resin varnish was prepared by mixing 70 parts of a (meth)acrylic acid ester ("A-DOG" manufactured by Shin-Nakamura Chemical Co., Ltd., (meth)acryloyl group equivalent 156 g / eq.), 20 parts of a carbodiimide curing agent ("V-03" manufactured by Nisshinbo Chemical Inc., carbodiimide group equivalent 216 g / eq., toluene solution with a non-volatile content of 50% by mass), 15 parts of a curing accelerator (1-benzyl-2-phenylimidazole (1B2PZ), MEK solution with a non-volatile content of 10% by mass), 6 parts of a polymerization initiator (Perkmyl D (manufactured by NOF Corporation, MEK solution with a non-volatile content of 20%)), 470 parts of inorganic filler B, 10 parts of cyclohexanone, and 10 parts of MEK, and dispersing the mixture uniformly using a high-speed rotating mixer.

[0232] A polyethylene terephthalate film ("AL5" manufactured by Lintec Corporation, thickness 38 μm) with a release layer was prepared as a support. The resin varnish was uniformly applied onto the release layer of this support so that the thickness of the resin composition layer after drying would be 200 μm. The resin varnish was then dried at 80°C to 120°C (average 100°C) for 6 minutes to produce a resin sheet including a support and a resin composition layer. In addition, a resin sheet including a support and a resin composition layer (thickness 40 μm) was produced using the same method, except that the thickness of the resin composition layer after drying was 40 μm.

[0233] [Melt viscosity and loss tangent measurement] Using a resin sheet with a resin composition layer thickness of 200 μm, only the resin composition layer was peeled off from the release PET (support) and compressed in a mold to prepare a pellet for measurement (diameter 18 mm, 1.2 to 1.3 g).

[0234] Using a dynamic viscoelasticity measuring device (Rheosol-G3000 manufactured by UBM), 1 g of the sample resin composition layer was measured using parallel plates with a diameter of 18 mm, starting at 70°C and rising at a rate of 5°C / min to 180°C, with a temperature interval of 2.5°C, a frequency of 1 Hz, and a strain of 1 deg. After measuring the dynamic viscoelasticity, a graph was created with temperature on the horizontal axis and melt viscosity or loss tangent on the vertical axis, and the melt viscosity (poise) and loss tangent (tanδ) at the molding temperature were calculated.

[0235] [Measurement of dielectric loss tangent of cured product] A release PET film ("501010" manufactured by Lintec Corporation, 38 μm thick, 240 mm square) was placed on a glass cloth-based epoxy resin double-sided copper-clad laminate ("R5715ES" manufactured by Panasonic Electric Works, Ltd., 0.7 mm thick, 255 mm square) so that the untreated surface of the release PET film was in contact with the laminate, and the four sides of the release PET film were fixed with polyimide adhesive tape (10 mm wide).

[0236] The resin sheets (200 mm square) with a 40 μm-thick resin composition layer prepared in the Examples and Comparative Examples were centrally laminated to the release surface of a release PET film ("501010" manufactured by Lintec Corporation) using a batch-type vacuum pressure laminator (Nikko Materials Co., Ltd., two-stage build-up laminator, CVP700) so that the resin composition layer was in contact with the release surface. The lamination was performed by reducing the pressure to 13 hPa or less for 30 seconds, and then pressing the film at 100°C and a pressure of 0.74 MPa for 30 seconds.

[0237] Next, the release PET (support) was peeled off from the resin sheet, and the sheet was placed in a 130°C oven for 30 minutes at 130°C, and then transferred to a 200°C oven for 90 minutes at 200°C, where it was thermally cured to obtain a cured product for evaluation.

[0238] The "cured product for evaluation" was cut into test pieces measuring 1.5 mm in width and 80 mm in length, and the dielectric loss tangent (Df) of each test piece was measured by the cavity resonance perturbation method using an "HP8362B" manufactured by Agilent Technologies, Inc., at a measurement frequency of 5.8 GHz and a measurement temperature of 23°C. Measurements were carried out on three test pieces, and the average value was calculated.

[0239] [Evaluation of void occurrence] <Preparation of samples for evaluation of mold underfill properties> (1) Preparation of evaluation board An evaluation substrate was fabricated in which a semiconductor chip (960 μm long, 1350 μm wide, 200 μm thick) was flip-chip bonded onto a glass substrate (38 mm square, 1 mm thick). The semiconductor chips were connected to the glass substrate using gold bumps (60 μm diameter, 240 μm pitch) so that there was a 30 μm gap between the glass substrate and the semiconductor chips, with 4 chips arranged vertically and 3 chips horizontally, for a total of 12 chips.

[0240] (2) Resin sheet mold underfill Using a batch-type vacuum pressure laminator (a two-stage build-up laminator "CVP700" manufactured by Nikko Materials Co., Ltd.), a 200 μm-thick resin composition layer was placed so as to cover the semiconductor chip of the evaluation substrate, and laminated to obtain evaluation substrate A. This lamination was performed by reducing the pressure to 13 hPa or less for 30 seconds, and then pressing at a molding temperature of 100 to 140°C and a pressure of 0.74 MPa for 30 seconds.

[0241] (3) Hardening of the resin sheet Evaluation substrates A of Examples 2, 4, and 7 and Comparative Examples 2 and 3 were placed in a 130°C oven under a temperature condition of 130°C and subjected to a pre-cure process for 30 minutes, and then transferred to a 200°C oven under a temperature condition of 200°C and subjected to a post-cure process for 90 minutes to thermally cure the resin composition layer, thereby obtaining evaluation substrates B.

[0242] Evaluation substrates A of Examples 1, 3, 5, and 6 and Comparative Example 1 were not subjected to a pre-cure process, but were placed in an oven at 200°C under a temperature condition of 200°C, and then subjected to a post-cure process for 90 minutes to thermally cure the resin composition layer, thereby obtaining evaluation substrates B.

[0243] <Void evaluation> The number of semiconductor chips in which voids occurred in the resin composition between the semiconductor chip and the glass substrate was counted using a digital microscope (Keyence Corporation, "VHX-7000") for evaluation substrate A and evaluation substrate B. The occurrence of voids in evaluation substrate B was evaluated according to the following criteria. 〇: Number of voids is 0 △: Number of voids is 1 to 3 ×: Number of voids is 4 or more

[0244] [Table 1]

Claims

1. (I) a step of laminating a resin composition layer of a resin sheet having a support and a resin composition layer provided on the support on a semiconductor chip package in which at least one semiconductor chip is mounted on a circuit board, and performing mold underfill; and (II) a step of thermally curing the resin composition layer; 1. A method for manufacturing a semiconductor chip package, comprising, in this order: A method for manufacturing a semiconductor chip package, wherein the resin composition layer has a loss tangent of 0.05 or more and 1.3 or less at a temperature at which mold underfilling is performed.

2. 2. The method for producing a semiconductor chip package according to claim 1, wherein the temperature at which the mold underfill is performed in step (I) is 70° C. or higher and 180° C. or lower.

3. 2. The method for producing a semiconductor chip package according to claim 1, wherein in step (II), the resin composition layer is subjected to a heat treatment in which it is maintained at a temperature T1, and then subjected to a heat treatment in which it is maintained at a temperature T2 higher than the temperature T1.

4. The method for producing a semiconductor chip package according to claim 1 , wherein the resin composition layer contains (A) an inorganic filler.

5. 5. The method for producing a semiconductor chip package according to claim 4, wherein the content of the inorganic filler (A) is 65% by mass or more when the nonvolatile components of the resin composition layer are taken as 100% by mass.

6. 2. The method for manufacturing a semiconductor chip package according to claim 1, wherein the melt viscosity of the resin composition layer is 1,000 poise or more and 10,000 poise or less.

7. 2. The method for manufacturing a semiconductor chip package according to claim 1, wherein a gap between the circuit board and the semiconductor chip is 60 [mu]m or less.

8. 4. The method for manufacturing a semiconductor chip package according to claim 3, wherein the temperature T2 is 150[deg.] C. or higher.

9. 4. The method for manufacturing a semiconductor chip package according to claim 3, wherein the difference T2-T1 between the temperature T1 and the temperature T2 is 20° C. or more.

10. 4. The method for manufacturing a semiconductor chip package according to claim 3, wherein the temperature T1 is 50[deg.] C. or higher.

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