Laminate

Abstract

To provide a laminate that can sufficiently suppress foreign matter when the substrate is peeled off. [Solution] A laminate comprising a base material and a resin composition layer formed on the base material, The resin composition layer comprises inorganic particles, epoxy resin, and a silane coupling agent, and has a thickness of 0.10 mm or more and 1.00 mm or less, the ratio of the inorganic particles to the solid content of the resin composition layer is 50% by mass or more and 99% by mass or less, the particle diameter D50 of the cumulative particle size distribution of the inorganic particles based on volume, where the cumulative 50% from the fine particle side is 10 μm or less, and the silane coupling agent has a Hansen solubility parameter polarization term dP of 2 or more and 10 or less, in a laminate.

Description

[Technical Field]

[0001] The present invention relates to laminates, and more particularly to laminates for sealing materials. [Background technology]

[0002] In the semiconductor field, chips are protected and reliability is ensured by encapsulating materials consisting of resin and fillers. In recent years, from the viewpoint of handling, laminates in which a resin composition layer containing inorganic particles and resin is formed in a sheet-like manner on a substrate have been considered as encapsulating materials for electronic components. Such laminates have improved handling properties because they contain a substrate before being applied to various electronic components. Such encapsulating materials can generally contain inorganic particles and resin, as described in Patent Document 1. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2021-145117 [Overview of the project] [Problems that the invention aims to solve]

[0004] When applying this sheet-like laminate to various electronic components, the substrate can be peeled off, allowing only the resin composition layer necessary for sealing to be used. However, as a result of our investigations, we found that in the laminate described above, when the substrate is peeled off, a part of the surface of the resin composition layer is damaged, resulting in a decrease in sealing performance. Therefore, the embodiment of the present invention aims to provide a laminate capable of sufficiently suppressing defects when the substrate is peeled off. [Means for solving the problem]

[0005] One aspect of the present invention is: A laminate comprising a substrate and a resin composition layer formed on the substrate, The resin composition layer comprises inorganic particles, epoxy resin, and a silane coupling agent, and has a thickness of 0.10 mm or more and 1.00 mm or less. The ratio of the inorganic particles to the solid content of the resin composition layer is 50% by mass or more and 99% by mass or less. The particle size D50 of the cumulative particle size distribution based on volume of the inorganic particles, where the cumulative percentage from the finest particles is 50%, is 10 μm or less. The silane coupling agent is a laminate in which the polarization term dP of the Hansen solubility parameter is between 2 and 10.

[0006] Aspect 2 of the present invention is, The silane coupling agent is given by formula (1): X 3-n Me n -Si-Y···(1) (In the formula, Me is a methyl group, X is a hydrolysis group, Y is a monovalent organic group, and n is 0, 1, or 2.) The laminate described in Embodiment 1 is a compound represented by [the formula shown].

[0007] A third aspect of the present invention is: The inorganic particles have 0.5 isolated OH groups per nm. 2 The above is the laminate described in embodiment 1 or 2.

[0008] Aspect 4 of the present invention is The inorganic particles are alumina particles, and the laminate is as described in any one of embodiments 1 to 3.

[0009] Aspect 5 of the present invention is Furthermore, the laminate according to any one of embodiments 1 to 4 contains a solvent.

[0010] Aspect 6 of the present invention is, The laminate according to any one of embodiments 1 to 5, wherein the mass ratio of the silane coupling agent content to the inorganic particle content is 1:0.0001 to 1:0.05. [Effects of the Invention]

[0011] According to an embodiment of the present invention, it is possible to provide a laminate capable of sufficiently suppressing defects during substrate peeling.

Embodiments for Carrying Out the Invention

[0012] The inventors of the present invention have intensively studied to provide a laminate capable of sufficiently suppressing defects during substrate peeling. The inventors of the present invention considered that the main cause of the occurrence of defects is aggregates of inorganic particles. Then, in addition to using predetermined inorganic particles and an epoxy resin, it was conceived to contain a silane coupling agent having a polarization term dP of a predetermined Hansen solubility parameter. As a result, due to the improvement in the compatibility (miscibility) of the inorganic particles and the epoxy resin via the silane coupling agent, aggregation of the inorganic particles can be suppressed, and as a result, a laminate capable of sufficiently suppressing foreign matter during substrate peeling has been realized. Hereinafter, the requirements of the present embodiment will be described in detail.

[0013] [Laminate] The laminate according to the present embodiment is a laminate including a substrate and a resin composition layer formed on the substrate, [[ID=二十]]The resin composition layer includes inorganic particles, an epoxy resin, and a silane coupling agent, and has a thickness of 0.10 mm or more and 1.00 mm or less, <{} the ratio of the inorganic particles to the solid content of the resin composition layer is 50% by mass or more and 99% by mass or less, the particle diameter D50 of 50% cumulative from the fine particle side of the volume-based cumulative particle size distribution of the inorganic particles is 10 μm or less, the silane coupling agent has a polarization term dP of the Hansen solubility parameter of 2 or more and 10 or less. The above laminate can sufficiently suppress foreign matter during substrate peeling.

[0014] In this embodiment, the substrate is preferably in the form of a film, and a general polymer film can be used. Examples of polymer films include polyethylene film, polyolefin films such as polypropylene film, vinyl films such as polyvinyl chloride film, polyester films such as polyethylene terephthalate film, polycarbonate film, acetylcellulose film, and tetrafluoroethylene film. The thickness of the substrate is not particularly limited, but from the viewpoint of excellent workability and drying properties, 20 to 200 μm is preferred. In one embodiment of the present invention, the laminate may also have the substrate laminated to the surface of the resin composition layer opposite to the surface having the substrate.

[0015] In this embodiment, the resin composition layer is formed on a substrate and includes inorganic particles, epoxy resin, and a silane coupling agent. The components of the resin composition layer will be described below.

[0016] The "resin composition layer" in the present invention has fluidity when heated and pressurized. The resin composition layer includes, for example, an uncured resin composition layer (also called a Stage A resin composition) and a resin composition layer obtained by partially curing the uncured resin composition layer (also called a Stage B resin composition). If the resin composition layer contains a solvent, for example, an uncured (Stage A) resin composition layer can be obtained by applying a liquid resin composition to a substrate and then removing a portion of the solvent by evaporation or the like. Furthermore, as will be described later, a Stage B resin composition layer can be obtained by partially curing the resin by further removing the solvent from the uncured (Stage A) resin composition layer.

[0017] In one embodiment of the present invention, the resin composition layer may contain a solvent. When the resin composition layer contains a solvent, it flows easily, can be easily deformed to conform to the fine structure of the IC chip and substrate, and can seal a dense structure without gaps. Known solvents can be used, and are not limited as long as they can dissolve epoxy resin, but examples include alcohol-based solvents, ketone-based solvents, ether-based solvents, ester-based solvents, amine-based solvents, amide-based solvents, halogen-based solvents, hydrocarbon-based solvents, nitrile-based solvents, etc. From the viewpoint of being a good solvent for epoxy resin and having excellent coatability of the resulting resin composition, it is preferable that the resin composition contains one or more solvents selected from the group consisting of ketone-based solvents and ester-based solvents.

[0018] Examples of ketone solvents include acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, and cyclohexanone. Examples of ester solvents include methyl acetate, ethyl acetate, butyl acetate, isobutyl acetate, n-propyl acetate, amine acetate, and sec-butyl acetate. The resin composition layer preferably contains one or more selected from the group consisting of methyl ethyl ketone, cyclopentanone, and cyclohexanone.

[0019] The solvent content in the uncured resin composition layer and the semi-cured resin composition layer is 0.001% by mass or more, preferably 10% by mass or less, relative to the total mass of the resin composition layer. When the solvent content is within this range, the fluidity during heating and pressurizing is good, and the aggregation and sedimentation of inorganic particles are prevented, making it easier to improve sealing performance. A semi-cured resin composition layer can be produced, for example, by further drying the uncured resin composition layer, reducing the amount of solvent by heating and pressurizing, or by reacting it with an epoxy resin. In the present invention, the amount of solvent in the semi-cured resin composition layer is less than the amount of solvent in the uncured resin composition layer. The amount of solvent in the resin composition layer can be determined, for example, from the change in mass of the resin composition layer before and after heating such as drying, and specifically by the method described in the examples below.

[0020] [Inorganic particles] In this embodiment, the resin composition layer contains inorganic particles. The inclusion of inorganic particles reduces the dimensional change rate of the entire resin composition layer, making it less likely for peeling or cracking to occur after semiconductor chip encapsulation, thereby improving reliability. As inorganic particles, ceramics such as silica, alumina, aluminum nitride, boron nitride, silicon nitride, and silicon carbide are preferred. In particular, from the viewpoint of dimensional stability of the resin composition layer, alumina or silica is preferred, and from the viewpoint of thermal conductivity of the resin composition layer, alumina, aluminum nitride, boron nitride, silicon nitride, and silicon carbide are preferred. Since ceramics have high thermal conductivity, using ceramic particles can improve the heat dissipation performance of the resin composition layer. Furthermore, when insulating ceramics are used as inorganic particles, short circuits of semiconductor devices can be suppressed. For this reason, it is more preferable that the inorganic particles are insulating ceramic particles, and specifically, alumina, aluminum nitride, boron nitride, and silicon nitride are more preferable. Among these, alumina is even more preferred from the viewpoint of achieving both thermal dimensional stability and thermal conductivity of the resin composition layer.

[0021] When alumina is selected as the inorganic particle, it can be manufactured by known methods. Examples include the Bayer process, ammonium alum process, ammonium aluminum carbonate hydroxide process (AACH process), solvent extraction, organoaluminum hydrolysis (aluminum alkoxide process), CZ process, Bernoulli process, Chiroporous process, Bridgman process, EFG process, and other melt growth methods.

[0022] In the Bayer process, raw alumina can be produced by calcining aluminum hydroxide obtained from bauxite. Furthermore, the ammonium alum method, AACH method, solvent extraction method, and aluminum alkoxide method are preferable because they can produce high-purity raw alumina with low uranium and thorium content, which can adversely affect electronic components.

[0023] (Particle size distribution of inorganic particles) The particle size of the inorganic particles is such that the particle size D50 (hereinafter sometimes simply referred to as "D50") at which 50% of the cumulative particle size distribution from the finest particle side of the volume-based cumulative particle size distribution of the inorganic particles is 10 μm or less. This can improve the sealing properties of the resin composition layer, especially the filling properties into narrow spaces between wiring. The D50 of the inorganic particles is preferably 5.5 μm or less, more preferably 5.0 μm or less, and even more preferably 3.0 μm or less. From the viewpoint of achieving good dispersibility in epoxy resin and easily suppressing defects when peeling off the substrate, the D50 of the inorganic particles is preferably 0.5 μm or more, more preferably 1.0 μm or more, and even more preferably 1.5 μm or more. Controlling the particle size to less than 0.5 μm may reduce the roundness because spheroidization becomes difficult. Also, depending on the object to be sealed, particles with a D50 greater than 10 μm may not be able to fill narrow areas during the sealing process.

[0024] The D50 of inorganic particles can be determined, for example, by measuring the particle size distribution of inorganic particles using the laser diffraction method with a Microtrac MT3300EXII laser particle size distribution analyzer manufactured by Microtrac-Bell Co., Ltd. The particle size measurement of inorganic particles in a resin composition layer can be performed by removing the resin contained in the resin composition layer, for example by dissolving it with an organic solvent or by thermally decomposing the resin by heating it to a temperature of 500°C or higher, separating only the inorganic particles, and then using those inorganic particles.

[0025] To easily obtain inorganic particles of a desired size, a grinding step may be included in the manufacturing process. The inorganic particles can be ground using known methods such as a vibratory mill, bead mill, ball mill, or jet mill, and may be ground in either a dry or wet state.

[0026] (Average roundness of inorganic particles) The inorganic particles are preferably spherical, and the average roundness is preferably 0.80 or more and 0.99 or less, more preferably 0.90 or more and 0.95 or less. When the average roundness of the inorganic particles is within the above range, it is easy to increase the filling rate of the inorganic particles into the epoxy resin, and sedimentation in the resin composition hardly occurs and the dispersibility is improved, so that good sealing properties can be realized. When the average roundness of the inorganic particles is high, the kneadability with the epoxy resin is also good, so that the fluidity of the resin composition after kneading is increased and it is easy to form into a sheet shape.

[0027] The roundness (SPHT) can be analyzed in accordance with ISO 9276-6. SPHT = 4πA / P 2 It is obtained from. In the formula, A is the measured value of the area of the projected particle image, and P is the measured value of the outer peripheral length of the particle projected image. The average roundness of the inorganic particles is measured by a measuring device (for example, CAMSIZER X2 (manufactured by VERDER Scientific)) based on the principle of dynamic image analysis in accordance with ISO 13322-2. The measurement of the average roundness of the inorganic particles in the resin composition layer can be carried out by removing the epoxy resin etc. contained in the resin composition layer by dissolving it with an organic solvent etc., heating it to a temperature of 5**0** C or more and thermally decomposing it etc., separating only the inorganic particles, and using those inorganic particles.

[0028] (BET specific surface area of inorganic particles) Spherical particles are preferred for the inorganic particles from the viewpoint of fluidity with the resin, and the BET specific surface area measured by the nitrogen adsorption method, although it depends on the average particle diameter, is preferably 0.2 m 2 / g or more and 10 m 2 / g or less, more preferably 0.2 m 2 / g or more and 5 m 2 / g or less, still more preferably 0.3 m 2 / g or more and 3 m 2 / g or less, even more preferably 0.35 m 2 / g or more and 1 m 2 / g or less. By setting it within this range, the fluidity of the resin composition after kneading can be increased, and the sealing properties of the obtained resin composition layer become good.

[0029] The BET specific surface area is measured in accordance with JIS-Z8830(2013). If inorganic particles are present in the resin composition layer, the resin in the resin composition layer can be removed by dissolving it with an organic solvent, heating it to a temperature of 500°C or higher to thermally decompose the resin, and only the inorganic particles can be separated. The specific surface area can then be measured using these inorganic particles.

[0030] The flame melting method is preferred as a method for producing inorganic particles having the desired roundness and BET surface area. The flame melting method is a method in which a raw material (e.g., alumina) is sprayed into a flame, liquefied, and then cooled and solidified. According to the flame melting method, inorganic particles can be obtained while maintaining their particle size almost. In the flame melting method, the temperature of the flame melting furnace is preferably 1000°C or higher. In particular, in the flame melting method, by setting the raw material supply rate to 50 kg / h or less, preferably 10 kg / h or less, the amount of thermal energy applied to the inorganic particles can be controlled within a predetermined range, making it easier to obtain inorganic particles that satisfy the above-mentioned predetermined requirements.

[0031] After the flame melting described above, inorganic particles can be collected and classified using a cyclone and / or bag filter to obtain inorganic particles with the desired properties.

[0032] After classification, the obtained inorganic particles may be immersed in an acidic solution such as hydrochloric acid. This modifies the surface of the inorganic particles and can further increase the number of isolated OH groups, as described later. Hydrochloric acid is preferred as the acidic solution for immersion due to the ease of adjusting the concentration. The concentration of the acidic solution is preferably 1M to 12M, more preferably 1M to 10M, and even more preferably 2M to 5M. The mass ratio of inorganic particles to acidic solution during immersion is preferably 1:2 to 1:10. The immersion time is preferably 5 hours or more. During immersion, the mixture may be heated as appropriate to shorten the immersion time, for example, to 50 to 90°C. After immersion, washing and drying are preferred.

[0033] Inorganic particles have 0.5 isolated OH groups per nm. 2 Preferably, the value is 0.9 particles / nm.2 The above is more preferable, 2.0 pieces / nm 2 The above is even more preferable. This allows for stronger interaction with the silane coupling agent, and as a result, the compatibility between the inorganic particles and the epoxy resin via the silane coupling agent can be further improved. Furthermore, it becomes easier to obtain laminates with a good appearance. On the other hand, the number of isolated OH groups is 3.0 / nm. 2 It is preferable that the value be less than this. This makes it easier to suppress aggregation between inorganic particles. Furthermore, it makes it easier to obtain a laminate with a good appearance.

[0034] The number of isolated OH groups in inorganic particles can be quantified using the Karl Fischer method (moisture vaporization-titration method) in accordance with JIS K 0068:2001 "Method for Measuring Moisture Content in Chemical Products". Moisture detected in the Karl Fischer measurement can be considered to originate from the OH groups of the inorganic particles, and the moisture detected when the temperature is raised from 550°C to 900°C over 30 minutes can be considered to be moisture originating from isolated OH groups. If inorganic particles are contained in a resin composition, the inorganic particles can be separated by dissolving the resin with an organic solvent or the like before measurement. Furthermore, the water detected in the Karl Fischer assay is thought to be formed when two OH groups condense to form one water molecule, and the number of OH groups can be determined by the following formula (2). Number of OH groups [pcs / nm 2 ] = 0.0662 × (Moisture content [ppm]) / (Specific surface area of ​​inorganic particles [m²]) 2 / g])···(2)

[0035] In this embodiment, the resin composition layer includes an epoxy resin. Because epoxy resin has high dimensional stability against external energy such as stress and heat, it is considered that it is easier to obtain a laminate that can suppress chipping when the substrate is peeled off. Examples of epoxy resins include bisphenol A type epoxy resin, bisphenol AP type epoxy resin, bisphenol AF type epoxy resin, bisphenol B type epoxy resin, bisphenol BP type epoxy resin, bisphenol C type epoxy resin, bisphenol E type epoxy resin, bisphenol F type epoxy resin, bisphenol G type epoxy resin, bisphenol M type epoxy resin, bisphenol S type epoxy resin, bisphenol P type epoxy resin, bisphenol PH type epoxy resin, bisphenol TMC type epoxy resin, bisphenol Z type epoxy resin, bisphenol S type epoxy resin such as hexanediol bisphenol S diglycidyl ether, novolacphenol type epoxy resin, biphenyl type epoxy resin, naphthalene type epoxy resin, dicyclopentadiene type epoxy resin, bixylenol type epoxy resin such as bixylenol diglycidyl ether, hydrogenated bisphenol A type epoxy resin such as hydrogenated bisphenol A glycidyl ether, and dibasic acid modified diglycidyl ether type epoxy resins thereof, aliphatic epoxy resins, and phenylcyclohexyl type epoxy resins. Preferred epoxy resins include phenylcyclohexyl epoxy resins, naphthalene epoxy resins, phenolic epoxy resins, biphenyl epoxy resins, and bisphenol A epoxy resins. From the viewpoint of thermal conductivity, epoxy resins having mesogenic groups (sometimes referred to as mesogenic epoxy resins) are more preferred among these, and even more preferred are epoxy resins having mesogenic groups that exhibit a phase transition temperature in the temperature range of 100°C to 200°C during sealing and exhibit liquid crystalline properties. The resin composition layer may contain one or more epoxy resins.In other words, the resin included in the resin composition layer may contain one or more epoxy resins selected from the group consisting of phenylcyclohexyl epoxy resin, naphthalene epoxy resin, phenol epoxy resin, biphenyl epoxy resin, and bisphenol A epoxy resin, and may also contain thermoplastic polyimide.

[0036] In this embodiment, the polarization term dP of the Hansen solubility parameter of the epoxy resin is not particularly limited, but is preferably 1 to 20, and more preferably 5 to 15. The Hansen solubility parameter of epoxy resins can be measured using the solubility sphere method. The solubility sphere method is a method for calculating the Hansen solubility parameter of a target substance. This method involves dissolving or dispersing the target substance in a number of different solvents for which the Hansen solubility parameter has been established, and then determining the Hansen solubility parameter by conducting solubility tests to evaluate the solubility or dispersibility of the target substance in a specific solvent. The types of solvents used in the solubility test are preferably selected so that the sum of the dispersion term, polarity term, and hydrogen bonding term of the HP of each solvent differs widely among the solvents. More specifically, it is preferable to use 10 or more types of solvents, more preferably 15 or more types, and even more preferably 17 or more types of solvents for evaluation. Specifically, among the solvents used in the solubility test, a sphere is found that contains all the points in three dimensions of the solvent in which the target substance was dissolved or dispersed, with the points of the undissolved solvent outside the sphere, and has the smallest radius (solubility sphere). The coordinates of the center of this sphere are taken as the Hansen solubility parameter of the target substance. Solubility and dispersibility are evaluated by visually determining whether the target substance has dissolved or dispersed in the solvent, respectively. The specific method for the solubility test will be described in detail in the Examples section.

[0037] The dispersion term dD of the Hansen solubility parameter for epoxy resin is preferably 10 or higher, more preferably 12 or higher, even more preferably 14 or higher, even more preferably 15 or higher, preferably 25 or lower, and more preferably 20 or lower. When dD is within the above range, it is easier to suppress the generation of foreign matter when the laminate is peeled off the substrate. Furthermore, the hydrogen bonding term dH of the Hansen solubility parameter for epoxy resin is preferably 5.0 or higher, more preferably 5.5 or higher, even more preferably 6.0 or higher, preferably 15 or lower, and more preferably 10 or lower. When dH is within the above range, it is easier to suppress the generation of foreign matter when the laminate is peeled off the substrate.

[0038] In this embodiment, the ratio of inorganic particles to the solid content of the resin composition layer (also referred to as the "inorganic particle filling rate") is 50% by mass or more and 99% by mass or less. By setting the inorganic particle filling rate to 50% by mass or more, thermal conductivity can be increased. On the other hand, by setting the inorganic particle filling rate to 99% by mass or less, it becomes easier to suppress defects in the laminate when the substrate is peeled off. From the viewpoint of increasing thermal conductivity and further suppressing defects when the substrate is peeled off, the inorganic particle filling rate is more preferably 92% by mass or less, even more preferably 90% by mass or less, particularly preferably 88% by mass or less, preferably 60% by mass or more, more preferably 70% by mass or more, and even more preferably 80% by mass or more. In this embodiment, the solid content of the resin composition layer refers to the solid content that remains when the resin composition layer is heated, excluding components that evaporate or volatilize upon heating, such as the solvent mentioned above. Even components that are liquid at 25°C are included in the solid content if they are incorporated into the solid content of the resin composition layer upon heating. .

[0039] The alumina packing ratio can be determined, for example, by the following method: First, the volatile components such as solvents are removed by heating, and then the mass of the sheet-like resin composition (corresponding to the mass of "solids") is measured. Next, epoxy resin and other components contained in the sheet-like resin composition are removed by, for example, dissolving them in an organic solvent or thermal decomposing them by heating to a temperature of 500°C or higher, separating only the alumina particles, and the mass of these alumina particles is measured. The alumina packing ratio can then be calculated using these measurement results. Alternatively, the alumina packing ratio can also be calculated from the amount of sheet-like resin composition used.

[0040] In this embodiment, the resin composition layer contains a silane coupling agent, the polarization term dP of its Hansen solubility parameter being 2 or more and 10 or less. A dP of 2 or more effectively suppresses aggregation between inorganic particles. The dP of the silane coupling agent is more preferably 3 or more, and even more preferably 3.5 or more. On the other hand, a dP of 10 or less sufficiently improves the compatibility between inorganic particles and epoxy resin. The dP of the silane coupling agent is more preferably 9 or less, and even more preferably 8 or less. The silane coupling agent may be one type or two or more types.

[0041] The dispersion term dD of the Hansen solubility parameter of the silane coupling agent is preferably 10 or higher, more preferably 12 or higher, even more preferably 14 or higher, even more preferably 15 or higher, preferably 25 or lower, more preferably 20 or lower, and even more preferably 18 or lower. When dD is within the above range, it is easier to suppress the generation of foreign matter when the substrate is peeled off in the laminate. Furthermore, the hydrogen bonding term dH of the Hansen solubility parameter of the silane coupling agent is preferably 6.0 or higher, more preferably 6.5 or higher, even more preferably 7.0 or higher, preferably 15 or lower, and even more preferably 10 or lower. When dH is within the above range, it is easier to suppress the generation of foreign matter when the substrate is peeled off in the laminate.

[0042] The Hansen solubility parameter of silane coupling agents can be measured using the solubility sphere method, similar to the Hansen solubility parameter of epoxy resins.

[0043] As the silane coupling agent, a known one whose Hansen solubility parameter polarization term dP is 2 or more and 10 or less can be used. In one embodiment of the present invention, the silane coupling agent may be represented by the following formula (1): X 3-n Me n -Si-Y···(1) (In the formula, Me is a methyl group, X is a hydrolysis group, Y is a monovalent organic group, and n is 0, 1, or 2.)

[0044] In formula (1), X (hydrolysis group) can be, for example, a methoxy group (CH3O-), an ethoxy group (CH3CH2O-), a propoxy group (CH3CH2CH2O-), an isopropoxy group ((CH3)2CHO-), a chloro group, or a 2-methoxyethoxy group (CH3OCH2CH2O-). From the viewpoint of easily coating inorganic particles, a methoxy group (CH3O-) or an ethoxy group (CH3CH2O-) is preferred, and a methoxy group (CH3O-) is more preferred. n is preferably 0 or 1, and more preferably 0.

[0045] In formula (1), Y is a monovalent organic group. Y is preferably a C1-C20 alkyl group which may have a vinyl group, epoxy group, phenyl group, styryl group, methacrylic group, acrylic group, amino group, ureido group, mercapto group, or isocyanate group at its terminus. Part of the carbon skeleton may be substituted with -O-, -NH-, -S-, -CO-, or -COO- as long as they are not adjacent. Among these, an unsubstituted C1-C20 alkyl group having a vinyl group, a phenyl group, or an epoxy group is more preferred. An unsubstituted C1-C20 alkyl group is even more preferred. This improves the dispersibility of the inorganic particles in the resin and makes it easier to suppress aggregation between inorganic particles.

[0046] In formula (1), Y is preferably a linear alkyl group having 1 to 20 carbon atoms, with the number of carbon atoms being preferably 2 or more, more preferably 5 or more, and even more preferably 8 or more. This makes it easier to obtain the effect of suppressing aggregation between inorganic particles due to steric hindrance of the silane coupling agent.

[0047] Examples of the above silane coupling agents include decyltrimethoxysilane, tetramethoxysilane, vinyltrimethoxysilane, 7-octenyltrimethoxysilane, 8-glycidoxyoctyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, hexamethyldisilazane, phenyltrimethoxysilane, glycidoxyoctyltrimethoxysilane, and 2-phenylethyl Dimethoxysilane, 2,2-diphenylethyltrimethoxysilane, vinyltrichlorosilane, vinyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropylethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-Methacryloxypropyltriethoxysilane, 3-Acryloxypropyltrimethoxysilane, N-2(aminoethyl)3-aminopropylmethyldimethoxysilane, N-2(aminoethyl)3-aminopropyltrimethoxysilane, N-2(aminoethyl)3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethyl-ditylidene)propylamine, N-phenyl -3-aminopropyltrimethoxysilane, hydrochloride of N-(vinylbenzyl)-2-aminoethyl-3-aminopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, 3-chloropropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, bis(triethoxysilylpropyl)tetrasulfide, 3-isocyanatetopropyltriethoxysilane, hexamethyldisilazane, etc. can be used. Among these, vinyl-based silane coupling agents are preferred because they easily prevent aggregation of inorganic particles and increase tensile strength.

[0048] In this embodiment, the mass ratio of the silane coupling agent content to the inorganic particle content is preferably 1:0.0005 to 1:0.03, more preferably 1:0.001 to 1:0.02, and even more preferably 1:0.0015 to 0.01. When the mass ratio of the silane coupling agent content to the inorganic particle content is greater than these preferred lower limits, the surface modification properties of the inorganic particles tend to improve, and the compatibility with the resin tends to improve. When it is less than these preferred upper limits, the self-condensation of hydrolyzable groups remaining without bonding to the inorganic particle surface is suppressed, thereby suppressing aggregation of inorganic particles. This makes it easier to further improve the compatibility between the inorganic particles and the epoxy resin. Furthermore, it becomes easier to obtain laminates with a good appearance.

[0049] The resin composition layer has a thickness of 0.10 mm or more and 1.00 mm or less. A thickness of 0.10 mm or more can suppress partial exposure of the IC chip and the occurrence of surface irregularities when sealing the IC chip. A thickness of 1.00 mm or less can reduce the heating time required for sufficient curing and allow for a resin composition layer in which inorganic particles are uniformly dispersed. The thickness is preferably 0.80 mm or less, more preferably 0.60 mm or less, even more preferably 0.40 mm or less, preferably 0.13 mm or more, more preferably 0.15 mm or more, and even more preferably 0.20 mm or more. When the thickness of the resin composition layer is within the above range, inorganic particles (especially particles with small particle diameters) and epoxy resin flow more uniformly when heated and pressurized, making it less likely for voids to occur after sealing and curing, thus reducing the likelihood of defects. In addition, aggregation and sedimentation of inorganic particles (especially particles with small particle diameters) caused by evaporation of solvent from the surface when stored in the atmosphere are less likely to occur, and the sealing performance is more easily maintained over a long period of time.

[0050] The resin composition layer may, if necessary, contain known additives such as plasticizers, curing agents, curing accelerators, fillers, pigments, flame retardants, antioxidants, surfactants, compatibilizers, weathering agents, antiblocking agents, antistatic agents, leveling agents, and mold release agents, either alone or in combination of two or more, as long as the effects of the invention are not impaired. As an example of a preferred embodiment of the present invention, the sheet-like resin composition comprises alumina particles, epoxy resin, silane coupling agent, solvent, and curing agent. Examples of curing agents include amine-based curing agents such as 4,4-diaminodiphenylmethane.

[0051] [Method for manufacturing laminates] The laminate according to this embodiment is obtained by mixing predetermined inorganic particles, epoxy resin, and silane coupling agent in predetermined ratios using a commonly used known method, and then applying the resulting mixture onto a substrate (and drying it as necessary) to form a resin composition layer on the substrate. The mixing method is not particularly limited, and a mill, mixer, stirring blades, etc., can be used.

[0052] One example of a method for manufacturing a laminate is to first mix alumina particles and a silane coupling agent in a predetermined ratio using a commonly used and known method, then mix in epoxy resin, a solvent, and a curing agent, apply the resulting mixture onto a substrate, and remove most of the solvent by hot air drying or the like to form a resin composition layer on the substrate. The method of applying the mixture is not particularly limited, but coating equipment such as a comma coater, lip coater, roll coater, gravure coater, die coater, or spin coater can be used. A known curing agent can be used, and known methods can be employed for mixing and curing. [Examples]

[0053] The following describes in detail this embodiment with reference to examples implemented to clarify its effects. However, this embodiment is not limited in any way to the following examples.

[0054] [Creation of alumina particles A0] As a raw material, high-purity aluminum metal obtained by the method described in Japanese Patent Publication No. 2010-106329 was prepared. Aluminum hydroxide was obtained from the aluminum metal by the sol-gel method according to the method described in Japanese Patent Publication No. 2018-048060, and then the aluminum hydroxide was calcined to obtain an alumina raw material.

[0055] Next, using a jet mill grinder (horizontal jet mill grinder PJM-280SP manufactured by Nippon Pneumatic Mfg. Co., Ltd.), the alumina raw material was processed under the conditions of a supply rate of 30 kg / h and a gauge pressure of 0.5 MPa at the air supply port during grinding, to obtain alumina raw material particles with an average particle diameter of approximately 2 μm for the secondary particles.

[0056] The obtained alumina raw material particles were fed into a flame melting furnace and melted to obtain spherical alumina particles. The ambient temperature inside the flame melting furnace was set to 1250°C and the raw material supply rate to 5 kg / h. The obtained alumina particles were recovered using a cyclone and subjected to classification by cyclone classification to remove particles larger than 5 μm, thereby obtaining alumina particle A0 (D50 = 2.6 μm). In the examples, the D50 of the alumina particles was measured by laser diffraction using the "Microtrac MT3300EXII" laser particle size distribution analyzer manufactured by Microtrac-Bell Co., Ltd.

[0057] [Creation of alumina particles A] As the raw material alumina, γ-alumina obtained by the ammonium alum method (average particle size of primary particles calculated from the BET specific surface area value below was 13 nm) was used. The BET specific surface area of ​​this γ-alumina obtained by nitrogen adsorption method was 120 m². 2 The value was / g. Before grinding, 4% by mass of propylene glycol was added to the raw alumina as a surface protective agent and mixed.

[0058] Next, using a jet mill grinder (horizontal jet mill grinder PJM-280SP manufactured by Nippon Pneumatic Mfg. Co., Ltd.), the alumina raw material was processed under the conditions of a supply rate of 30 kg / h and a gauge pressure of 0.5 MPa at the air supply port during grinding, to obtain alumina raw material particles with an average particle diameter of approximately 2 μm for the secondary particles.

[0059] The obtained alumina raw material particles were fed into a flame melting furnace and melted to obtain spherical alumina particles. The ambient temperature inside the flame melting furnace was set to 1250°C and the raw material supply rate to 5 kg / h. The obtained alumina particles were recovered using a cyclone and subjected to classification by cyclone classification to remove particles larger than 5 μm, thereby obtaining alumina particle A (D50 = 2.3 μm).

[0060] [Creation of Alumina Particles B2] Alumina particle A and the same alumina raw material particles were introduced into a flame melting furnace and melted to obtain spherical alumina particles. The ambient temperature inside the flame melting furnace was set to 1250°C and the raw material supply rate to 5 kg / h. The obtained alumina particles were recovered using a cyclone and subjected to classification by cyclone classification to remove particles larger than 10 μm to obtain alumina particle B (D50 = 5.1 μm).

[0061] The obtained alumina particles B were immersed in 2M hydrochloric acid. The mass ratio of alumina particles to hydrochloric acid during immersion was 1:5, the immersion temperature was 80°C, and the immersion time was 12 hours. After immersion, the particles were immersed in water multiple times. The water was changed each time, and this process was repeated until the water after immersion became neutral. After removing the water, the particles were left to stand at 80°C for 6 hours and dried to obtain alumina particles B2.

[0062] The following measurements were performed on each alumina particle.

[0063] [Number of isolated OH groups in alumina particles] The number of isolated OH groups in alumina particles was quantified using the Karl Fischer method (moisture vaporization-titration method) in accordance with JIS K 0068:2001 "Method for Measuring Moisture Content of Chemical Products". Moisture detected in the Karl Fischer measurement was considered to originate from the OH groups of the alumina particles, and moisture detected at 900°C was considered to be moisture originating from isolated OH groups. In addition, the water detected in the Karl Fischer assay is thought to be formed when two OH groups condense to form one water molecule, and the number of OH groups was determined by the following formula (2). Number of OH groups [pcs / nm 2 ] = 0.0662 × (Moisture content [ppm]) / (Specific surface area of ​​alumina particles [m²]) 2 / g])···(2)

[0064] [Preparation of each silane coupling agent] As silane coupling agents, KBM-3103, KBM-1003, KBM-1083, KBM-4803, and KBM-403 (all manufactured by Shin-Etsu Chemical Co., Ltd.) were prepared. In addition, silane coupling agents A and B, shown by the following structural formulas, were prepared. Silane coupling agent A (2-phenylethyltrimethoxysilane): [ka] Silane coupling agent B (2,2-diphenylethyltrimethoxysilane): [ka]

[0065] For each silane coupling agent, the Hansen solubility parameter was measured using the lysis sphere method as follows. A mixture was prepared by adding 1 mL of a solvent with known solubility parameters (Source: Polymer Handbook, 4th Edition) as shown in Table 1 to a transparent container, along with 1 mL of the target silane coupling agent. The resulting mixture was shaken, and the appearance of the liquid was visually observed. Based on the observation results, the solubility of the target silane coupling agent in the solvent was evaluated according to the evaluation criteria below. If the evaluation criterion was 1 or 2, it was determined that the solvent dissolved the sample; if the evaluation criterion was 0, it was determined that the solvent did not dissolve the sample. (Evaluation Criteria) 2: The mixture has a semi-transparent appearance. 1: The mixture is colorless and transparent. 0: The mixture appears cloudy or separated.

[0066] [Table 1] TIFF2026050201000004.tif134164

[0067] Based on the evaluation results of the solubility of the obtained silane coupling agent in the solvent, Hansen spheres were prepared using the Hansen solubility sphere method described above. The center coordinates of the obtained Hansen spheres were defined as the HSP value. The results are shown in Table 2.

[0068] [Table 2]

[0069] [Preparation of each epoxy resin] As epoxy resins, mesogenic epoxy resin (phenylcyclohexyl type epoxy resin) (A) (hereinafter also referred to as "ME") and bisphenol A type epoxy resin (ADEKA, EP-4100HF) (hereinafter also referred to as "BisA") were prepared. In addition, the solubility parameters of each epoxy resin were measured by the solubility sphere method, similar to the silane coupling agent. The dD, dP, and dH values ​​of ME were 16.7, 7.7, and 8.6, respectively, and the dD, dP, and dH values ​​of BisA were 17.8, 10.5, and 6.6, respectively. Here, mesogenic epoxy resin (A) is a prepolymer obtained by reacting trans-4-{4-(2,3-epoxypropoxy)phenyl}cyclohexyl=4-(2,3-epoxypropoxy)benzoate (an epoxy resin represented by the structural formula below) with 6-hydroxy-2-naphthoic acid. [ka]

[0070] <Fabrication of laminates> Laminates of Examples 1-12 and Comparative Examples 1-5 were prepared by mixing (kneading) each alumina particle, each silane coupling agent (hereinafter sometimes referred to as "SC agent"), each epoxy resin, and the curing agent in the predetermined ratios shown in Table 3 below. Detailed preparation methods are shown below.

[0071] (1) Silane coupling agent treatment The following treatment was performed to fix the silane coupling agent to the surface of the alumina particles. A slurry was prepared by mixing 50 g of alumina particles with 20 g of isopropanol. To the prepared slurry, 0.5% by mass of silane coupling agent was added relative to the alumina particles, followed by the addition of 0.02 g of formic acid, and the mixture was stirred for 30 minutes. Then, 0.2 g of 10% by mass aqueous ammonia was added, and the mixture was stirred for 60 minutes. The stirred slurry was heated at 120°C for 3 hours to remove the solvent, thereby obtaining alumina particles treated with the silane coupling agent.

[0072] Alumina particles treated with a silane coupling agent were subjected to thermogravimetric analysis using a differential thermogravimetric analyzer (NEXTA STA200, Hitachi High-Tech). The mass reduction ratio from the initial mass when the temperature was increased from 60°C to 500°C at a rate of 10°C / min was defined as the mass ratio of the silane coupling agent content to the alumina particles.

[0073] (2) Preparation of varnish An epoxy resin was dissolved in a mixed solvent of methyl ethyl ketone and cyclopentanone (mass ratio 3:1) to prepare a 30% by mass mixed solution. Furthermore, 4,4-diaminodiphenylmethane (manufactured by TCI) was added as a curing agent at a concentration of 4.14% by mass per 100% by mass of the mixed solution to prepare a varnish.

[0074] (3) Preparation of alumina particle / varnish mixture Alumina particles treated with a silane coupling agent (or alumina particles not treated with a silane coupling agent) were added to the obtained varnish, and the mixture was kneaded at 2000 rpm for 60 seconds using a rotation-orbit mixer (manufactured by Sinky Co., Ltd.) to prepare the alumina particle / varnish mixture.

[0075] (4) Film formation and drying The obtained alumina particle / varnish mixture was applied to a PET substrate, and a film was formed using an applicator to a dry thickness of 300 μm. The solvent was then evaporated by heating at 65°C for 5 minutes and 100°C for 15 minutes to obtain a laminate containing the substrate and the resin composition layer (uncured) formed on the substrate. The solvent content of the resin composition layer (uncured) was 0.1 to 3% by mass in all cases. The solvent content of the resin composition layer was determined by the following measurement. A 4 cm square sample was cut from the resin composition layer of each example and comparative example, along with the PET substrate, and the mass W1 (g) of the sample (with PET substrate) was measured. Next, the sample was heated at 150°C for 10 minutes using a fully exhausted oven to evaporate all the solvent contained in the sample. After that, it was left at room temperature for 5 minutes to return to room temperature, and the mass W2 (g) of the heated sample (with PET substrate) was measured. The PET substrate was peeled off the heated sample, and the mass W3 (g) of the PET substrate was measured. The masses of the sample before and after heating were determined by subtracting W3 (g) from W1 (g) and W2 (g), respectively. The value obtained by subtracting the mass of the sample after heating (W2-W3) from the mass of the sample before heating (W1-W3) was taken as the mass of solvent contained in the resin composition layer. The ratio of the mass of solvent to the mass of the sample before heating was taken as the solvent content (solvent amount). The formula for calculating the solvent content (solvent amount) is as shown in equation (1) below. Solvent volume (mass%) = {(W1-W3)-(W2-W3)} / (W2-W3) × 100···(1)

[0076] [Table 3]

[0077] The presence or absence of foreign matter and the appearance of the laminates obtained in Examples 1-12 and Comparative Examples 1-5 after substrate peeling were evaluated, and the results are summarized in Table 4 below.

[0078] <Evaluation of the presence or absence of foreign matter when peeling off the substrate> After storing the above laminate in a 25°C, 50% humidity environment for 10 days, the substrate and resin composition layer were separated. The presence or absence of foreign matter was evaluated after rubbing a 5mm square area of ​​the surface of the separated substrate with tweezers, and grades A to B were considered acceptable (sufficient suppression of damage during substrate separation). A: No visible foreign matter (powder) was generated. B: No visible foreign matter (powder) was generated on the substrate, but a small amount of foreign matter (powder) adhered to the tip of the tweezers. C: Visible foreign matter (powder) was generated on the substrate.

[0079] <Visual evaluation of laminated structures> The appearance of a 2cm x 2cm area of ​​the above laminate (on the resin composition layer side) was visually observed under an illuminance of 1000 lx, and the number of white spots caused by the aggregation of inorganic particles, etc., was evaluated as follows. A: Fewer than 8 white spots with a diameter of 2 mm or more. B: 8 to 15 white spots with a diameter of 2 mm or more. C: 15 to less than 22 white spots with a diameter of 2 mm or more.

[0080] [Table 4]

[0081] The results in Table 4 will be discussed below. The laminates of Examples 1 to 12, which satisfy the requirements of this embodiment, were able to sufficiently suppress defects during substrate peeling. On the other hand, the laminates of Comparative Examples 1 to 5, which did not satisfy the requirements of this embodiment, were unable to sufficiently suppress defects during substrate peeling.

Claims

1. A laminate comprising a substrate and a resin composition layer formed on the substrate, The resin composition layer comprises inorganic particles, epoxy resin, and a silane coupling agent, and has a thickness of 0.10 mm or more and 1.00 mm or less. The ratio of the inorganic particles to the solid content of the resin composition layer is 50% by mass or more and 99% by mass or less. The particle size D50 of the cumulative particle size distribution of the inorganic particles, based on volume, where 50% of the particles are from the finest particle side, is 10 μm or less. The silane coupling agent is a laminate in which the polarization term dP of the Hansen solubility parameter is 2 or more and 10 or less.

2. The silane coupling agent is defined by formula (1): X ３－ｎ Me ｎ -Si-Y・・・(1) (In the formula, Me is a methyl group, X is a hydrolysis group, Y is a monovalent organic group, and n is 0, 1, or 2.) The laminate according to claim 1, wherein the compound is represented by the compound.

3. The inorganic particles have 0.5 isolated OH groups per nm. ２ The laminate according to claim 1 or 2.

4. The laminate according to claim 1 or 2, wherein the inorganic particles are alumina particles.

5. The laminate according to claim 1 or 2, further comprising a solvent.

6. The laminate according to claim 1 or 2, wherein the mass ratio of the silane coupling agent content to the inorganic particle content is 1:0.0001 to 1:0.05.

Images