Agglomerated silica powder-reducing resin composition and semiconductor sealing material

Abstract

The present application provides a kind of silica powder, it is the silica powder of particle size 2.0 μm or less, not easy to condense, good operability, and easy to disperse when mixed with resin;And the resin composition and semiconductor sealing material containing above-mentioned silica powder.One kind of silica powder, volume reference cumulative diameter (D50) is 2.0 μm or less, the maximum particle size (D max ) determined by particle size measuring instrument using the following method is 5.0 μm or less.(determination method) the resin composition obtained by adding 67 parts by mass of silica powder to 100 parts by mass of bisphenol F type liquid epoxy resin, according to JIS K 5600-2-5, using particle size measuring instrument, the dispersibility of the above-mentioned silica powder in the above-mentioned epoxy resin is evaluated using histogram method, the maximum particle size (D max ) is determined.In addition, the same evaluation is carried out for 5 times, and the average value is used.

Description

TECHNICAL FIELD

[0001] The present application relates to a silica powder with reduced agglomeration and a resin composition and a semiconductor sealing material. BACKGROUND

[0002] In silica powders used for semiconductor sealing material applications, insulating substrate applications, and the like, agglomerated particles and coarse particles can cause package breakage, lead short-circuiting, unevenness on substrates, white spots, and the like, and thus it is desirable to reduce the number of such particles. Furthermore, when a silica powder containing coarse particles is compounded into a resin, the flowability of the resin can be reduced, and if such a resin composition is used as a semiconductor sealing material, semiconductor breakage, molding defects, and the like can easily occur. From these viewpoints, a silica powder that is less likely to agglomerate and has fewer coarse particles is desirable.

[0003] However, silica powders having an average particle diameter of 2.0 μm or less are known to be more likely to agglomerate due to forces (weight, liquid cross-linking forces, van der Waals forces, and the like) acting on the silica powder. Silica powders having such a particle diameter also have high adhesion to devices and containers, and thus there can be problems in that the silica powder clogs delivery piping and feeding machines, resulting in poor operability. Because of this background, the yield of silica powders having a particle diameter of 2.0 μm or less is very poor when fractionated using a sieve or the like, and it is difficult to produce a silica powder having fewer coarse particles. Furthermore, even vibrations generated by a sieve device can cause agglomeration and coarsening, and thus there can be problems in that the desired dispersibility is not obtained when mixed with a resin.

[0004] In recent years, in response to the demand for miniaturization, weight reduction, and high performance of electronic devices, in terms of the internal structure of semiconductors, thinning of components, miniaturization of gold wires, long span, high density of wiring pitch, and the like are rapidly progressing. As a sealing material for such semiconductors, a resin composition in which a silica powder having an even smaller average particle diameter is compounded as a filler is desirable, but as described above, silica powders having a small average particle diameter are likely to agglomerate and have poor operability. Therefore, a small particle diameter silica powder that is less likely to agglomerate and has a low content of coarse particles and is also excellent in operability is desirable.

[0005] In order to solve this problem, for example, in Patent Document 1, a silica powder having a BET of 2 m 2 / g or more and less than 30 m 2 / g, the content of particles having a particle size of 1.5 μm or more was 0.1% by mass or less. However, in Patent Literature 1, coarse particles were removed by wet classification, and the particle size distribution and the specific surface area were changed due to a decrease in fume components on the surface of the powder, and the dispersibility in a resin was decreased. Further, in Patent Literature 2, a spherical silica fine powder having a maximum value of the particle size distribution in the range of 1 μm to 10 μm, and a residue of coarse particles on a mesh of 45 μm of 0.01% by weight or less was proposed. However, in the method of Patent Literature 2, it was difficult to remove only coarse particles without changing the particle size distribution. Further, in these Patent Literatures 1 and 2, no study was made on a powder having a particle size of 2.0 μm or less.

[0006] Patent Literature 1: Japanese Patent Application Laid-Open No. 2016-204236

[0007] Patent Literature 2: Japanese Patent Application Laid-Open No. 2015-86120 SUMMARY

[0008] Therefore, an object of the present application is to provide a silica powder having a particle size of 2.0 μm or less, which is not easily aggregated, is good in handleability, and is easily dispersed when mixed with a resin; and a resin composition and a semiconductor sealing material each containing the above silica powder.

[0009] The present inventors made intensive studies, and as a result, found that all of the above problems can be solved by a silica powder having a maximum particle size (D max ) of 5.0 μm or less, measured by a particle size measuring instrument in a specific method, and thus completed the present application.

[0010] That is, the present application has the following modes.

[0011] [1] A silica powder having a volume-based cumulative diameter (D50) of 2.0 μm or less, and a maximum particle size (D max ) of 5.0 μm or less, measured by a particle size measuring instrument in the following method.

[0012] (Measurement method)

[0013] A resin composition was prepared by adding 67 parts by mass of the silica powder to 100 parts by mass of a bisphenol F-type liquid epoxy resin, and mixing the mixture by using a self-rotation / rotation mixer at a temperature of 30°C and a rotation speed of 2000 rpm for 3 minutes of self-rotation and 1 minute of rotation. The dispersibility of the silica powder in the epoxy resin was evaluated by using a particle size measuring instrument having a width of 90 mm, a length of 240 mm, and a maximum depth of 100 μm, and a distribution chart method in accordance with JIS K5600-2-5, and the maximum particle size (D max). In addition, the same evaluation was performed five times, and the average value was used.

[0014] [2] The silica powder according to [1], wherein the volume-based cumulative diameter (D90) is 2.5 μm or less.

[0015] [3] The silica powder according to [1] or [2], wherein the volume-based cumulative diameter (D100) is 4.7 μm or less.

[0016] [4] The silica powder according to any one of [1] to [3], wherein the specific surface area (BET) is 2 to 15 m 2 / g.

[0017] [5] The silica powder according to any one of [1] to [4], wherein the volume-based frequency of the volume-based cumulative diameter (D90) calculated from the following formula (1) with respect to the value of the volume-based cumulative diameter (D100) minus the volume-based cumulative diameter (D90) is 1.0 to 3.0,

[0018] (volume-based frequency of volume-based cumulative diameter (D90)) / (volume-based cumulative diameter (D100) - volume-based cumulative diameter (D90)) ··· (1).

[0019] [6] A resin composition containing the silica powder according to any one of [1] to [5] and a resin.

[0020] [7] The resin composition according to [6], wherein the resin contains a thermosetting resin.

[0021] [8] A semiconductor sealing material formed using the resin composition according to [6] or [7].

[0022] According to the present application, it is possible to provide a silica powder having a particle diameter of 2.0 μm or less, which is not easily aggregated, is excellent in handleability, and is easily dispersed when mixed with a resin; and a resin composition and a semiconductor sealing material containing the above-mentioned silica powder. DETAILED DESCRIPTION

[0023] The present application is explained in detail below, but the present application is not limited to the following modes. It should be noted that the notation of "to" in the present specification means "of and above and of and below". For example, "3 to 15" means 3 or more and 15 or less. In addition, in the present specification, "powder" means "a collection of particles".

[0024] [Silica powder]

[0025] The silica powder according to the present application is characterized in that the volume-based cumulative diameter (D50) is 2.0 μm or less, and the maximum particle diameter (D max ) measured using a particle size measuring instrument according to the following method is 5.0 μm or less.

[0026] (Measurement method)

[0027] A resin composition was prepared by adding 67 parts by mass of the silica powder to 100 parts by mass of a bisphenol F-type liquid epoxy resin, and mixing the mixture using a self-rotation / revolution mixer at a temperature of 30°C and a rotation speed of 2000 rpm for 3 minutes of self-rotation and 1 minute of revolution. The dispersion of the silica powder in the epoxy resin was evaluated using a particle size measuring instrument having a width of 90 mm, a length of 240 mm, and a maximum depth of 100 μm according to the distribution chart method, and the maximum particle diameter (D max ) was measured according to JIS K 5600-2-5. In addition, the same evaluation was performed five times, and the average value was used.

[0028] The silica powder according to the present application is not easily aggregated, is easy to handle, and is easily dispersed when mixed with a resin.

[0029] The volume-based cumulative diameter (D50) of the silica powder according to the present application is 2.0 μm or less, preferably 1.5 μm or less, more preferably 0.3 to 1.2 μm, and particularly preferably 0.4 to 1.0 μm. The silica powder according to the present application is not easily aggregated even when the D50 is 2.0 μm or less, is easy to handle, and is not easily aggregated with other particles when mixed with a resin, and thus is excellent in dispersibility. Note that, in the present specification, the volume-based cumulative diameter (D50) of the silica powder refers to the particle diameter at which the cumulative value is 50% in the volume-based cumulative particle size distribution measured using a laser diffraction scattering method (refractive index: 1.50). The cumulative particle size distribution is represented by a distribution curve in which the horizontal axis represents the particle diameter (μm) and the vertical axis represents the cumulative value (%). The volume-based cumulative particle size distribution measured using a laser diffraction scattering method (refractive index: 1.50) was measured using a laser diffraction scattering particle size distribution measuring instrument (manufactured by Beckman Coulter, Inc., product name "LS-13320XR"), water (refractive index: 1.33) was used as the solvent, and dispersion treatment using an ultrasonic generator (manufactured by SONICS MATERIALS INC, product name "VC-505") was performed for 2 minutes as a pretreatment.

[0030] The maximum particle diameter (D max ) of the silica powder according to the present application measured using a particle size measuring instrument according to the above method is 5.0 μm or less.

[0031] The grooves of the particle size analyzer are inclined and gradually become shallower. Therefore, if particles larger than the depth of the grooves are present, linear traces will remain on the film. Thus, by comparing the film-forming traces with the scale on the particle size analyzer, the presence or absence of aggregates and their particle sizes can be confirmed. In the particle size analyzer method of the present invention, the "maximum particle size (D)" is used to determine the particle size. max "Maximum particle size (D)" refers to the value of the linear trace remaining at the position of the largest particle size among the linear traces remaining on the film formed by the particle size analyzer. In this invention, the above evaluation is performed 5 times, and the average value is set as "maximum particle size (D)". max )".

[0032] The particle size distribution is performed as described above in a resin composition in which silica powder is dispersed in bisphenol F type liquid epoxy resin. This method allows for the evaluation of the dispersibility and degree of aggregation of the silica powder in the resin. The maximum particle size (D) of the silica powder involved in this invention, as determined by the particle size distribution using the above method, is... max The particle size is below 5.0 μm, which means that the aggregation of silica powder in the resin is suppressed. That is, the silica powder of the present invention is easy to disperse and not easy to aggregate when mixed with resin.

[0033] The bisphenol F type liquid epoxy resin used in particle size analyzer determination is preferably one with a viscosity of 3,000 to 4,500 mPa·s (25°C) and an epoxy equivalent of 160 to 175 g / eq.

[0034] The above maximum particle size (D) max Preferably, the micrometer size is 4.5 μm or less, and particularly preferably, it is 4.0 μm or less.

[0035] The volumetric cumulative diameter (D90) of the silica powder involved in this invention (hereinafter sometimes referred to as "D90") is preferably 2.5 μm or less, more preferably 2.2 μm or less, and even more preferably 2.0 μm or less. D90 refers to the particle size at which the cumulative value in the volumetric cumulative particle size distribution, measured using the same method as D50 described above, corresponds to 90% of the total particle size. That is, a D90 of 2.5 μm or less indicates silica powder with fewer coarsened particles due to agglomeration.

[0036] The volume-based cumulative diameter (D100) (hereinafter sometimes referred to as "D100") of the silica powder according to the present application is preferably 4.7 μm or less, more preferably 4.2 μm or less, and further preferably 4.0 μm or less. The D100 means the particle size at which the cumulative value is 100% in the volume-based cumulative particle size distribution measured by the same method as the D50 and D90 described above. The "D100 is 4.7 μm or less" means that coarse particles of 4.7 μm or more are substantially not present in the silica powder. In addition, "substantially not present" means that the ratio of coarse particles of 4.7 μm or more in the silica powder is less than 0.1 mass%. Such a silica powder is more easily handled, and in addition, when a resin composition for a semiconductor sealing material is produced, the risk of short-circuit failure due to the mixing of coarse particles into the interstices of the wiring is more easily reduced.

[0037] The volume-based frequency of the volume-based cumulative diameter (D90) calculated from the following formula (1) with respect to the difference between the volume-based cumulative diameter (D100) and the volume-based cumulative diameter (D90) of the silica powder according to the present application is preferably 1.0 to 3.0, more preferably 1.5 to 3.0, and further preferably 2.0 to 3.0.

[0038] (volume-based frequency of volume-based cumulative diameter (D90)) / (volume-based cumulative diameter (D100) - volume-based cumulative diameter (D90)) (1)

[0039] In formula (1), the "volume-based frequency of volume-based cumulative diameter (D90)" (hereinafter sometimes referred to as "volume-based frequency of D90") means the frequency of the particle size at which the cumulative value is 90% in the volume-based cumulative particle size distribution measured by the laser diffraction scattering method (refractive index: 1.50) described above. When the value of the volume-based frequency of D90 with respect to the difference between D100 and D90 of the silica powder is within the above range, agglomeration is less likely to occur, and coarse particles are less likely to be present. Such a silica powder is more easily handled, and in addition, when a resin composition for a semiconductor sealing material is produced, the risk of short-circuit failure due to the mixing of coarse particles into the interstices of the wiring is more easily reduced.

[0040] In addition, the difference between D100 and D90 (D100 - D90) is preferably 2.3 μm or less, and more preferably 2.0 μm or less. When the difference between D100 and D90 is within the above range, a silica powder having a narrower particle size distribution is obtained. Such a silica powder has fewer coarse particles and is more easily dispersed in a resin.

[0041] The ratio of D50 to D90 (D90 / D50) of the silica powder according to the present application is preferably 2.2 or less, more preferably 2.0 or less, and further preferably 1.4 to 2.0. If D90 / D50 is 2.2 or less, it is easy to obtain a silica powder having a narrower particle size distribution. Such a silica powder is less likely to agglomerate, and the handling properties become better, and thus is preferred.

[0042] The ratio of D50 to D100 (D100 / D50) of the silica powder according to the present application is preferably 5.0 or less, more preferably 4.0 or less, and further preferably 3.0 to 4.0. If D100 / D50 is 5.0 or less, it is easy to obtain a silica powder having a narrower particle size distribution. Such a silica powder is less likely to agglomerate, and the handling properties become better, and thus is preferred.

[0043] The specific surface area of the silica powder according to the present application, measured by the BET method, is preferably 2 to 15 m 2 / g, more preferably 3 to 12 m 2 / g, and further preferably 3 to 8 m 2 / g. The silica powder according to the present application has a small specific surface area, although the D50 is 2.0 μm or less. The silica powder according to the present application has a narrow particle size distribution, and the proportion of fine particles is small. In addition, the agglomeration of the particles with each other is suppressed, and thus it is easy to achieve the specific surface area in the above range. Note that, in the present specification, the measurement of the specific surface area by the BET method is performed using "Macsorb HM model-1208" (manufactured by Mountech).

[0044] From the viewpoint of the close thermal expansion rates of the semiconductor chip and the liquid sealing material, the heat resistance of the solder, the moisture resistance, and the low abrasion of the mold, the silica powder according to the present application is more preferably an amorphous silica powder produced by a method in which a crystalline silica powder is melted at a high temperature.

[0045] The silica powder according to the present application is preferably a spherical silica powder, and more preferably a spherical amorphous silica powder. As the degree of "sphericity", the average sphericity is preferably 0.85 or more. Further, the average sphericity can be calculated by reading the image of the particle taken by a stereomicroscope (for example, product name "Model SMZ-10", manufactured by Nikon Corporation), a scanning electron microscope, a transmission electron microscope, or the like into an image analysis device (for example, manufactured by Nippon Avionics Corporation, or the like), and measuring in the following manner. That is, the projected area (A) and the perimeter (PM) of the particle are measured from the photograph. If the area of a true circle with respect to the perimeter (PM) is defined as (B), the true circularity of the particle can be expressed as A / B. Therefore, if a true circle having the same perimeter as the perimeter (PM) of the sample particle is assumed, since PM = 2πr, B = πr 2 , it becomes B = π x (PM / 2π) 2 , and the sphericity of each particle can be calculated as sphericity = A / B = A x 4π / (PM) 2 . The sphericity of any 200 particles obtained in this manner is calculated, and the average value thereof is used as the average sphericity.

[0046] The silica powder can also be treated with a surface modifier. By treating with a surface modifier, the particles become less likely to agglomerate with each other, and the dispersibility in a resin becomes more excellent. When the silica powder is treated with a surface modifier, the entire surface of the particle can be modified, or a part of the surface thereof can be modified.

[0047] As the surface modifier, there is no particular limitation as long as it has the effect of the present application, and a surface modifier conventionally used in fillers such as silica powder can be appropriately used. For example, silane compounds, silazane compounds, aluminate coupling agents, titanate coupling agents, and the like can be exemplified. These can be used alone or two or more kinds can be used together.

[0048] [Method for producing silica powder]

[0049] Next, one embodiment of the method for producing the silica powder according to the present application will be described.

[0050] The silica powder according to the present embodiment can be produced by classifying a raw powder prepared by a conventionally known method. In the present specification, the "raw powder" means a silica powder containing coarse particles before the classification treatment. Further, the powder used to prepare the raw powder is described as "coarse raw powder".

[0051] As the method for producing the raw material powder, a publicly known method can be used, for example, a method in which a raw material powder is obtained by directly supplying a crude raw material powder to a high-temperature flame formed in a furnace, or a method in which a slurry containing a crude raw material powder is sprayed in a flame to remove a solvent and obtain a raw material powder, and the like.

[0052] The method for classifying the raw material powder is roughly classified into a dry method and a wet method.

[0053] As the dry method, for example, a sieve classification method, an air flow classification method, and the like can be exemplified. As the wet method, for example, a filter classification method in which a raw material powder is dispersed in a solvent and then passed through a filter to remove coarse particles, and a fluid classification method in which a raw material powder is made into a fluid state and coarse particles are removed using a difference in settling velocity can be exemplified.

[0054] The production method according to the present embodiment is preferably one including classifying the raw material powder by an air flow classification method from the viewpoint of not easily reducing the yield and preventing a decrease in dispersibility in a resin due to a change in particle size distribution and specific surface area.

[0055] The air flow classification is a method in which a raw material powder is dispersed in an air flow, and coarse particles are removed using gravity, inertial force, centrifugal force, or the like of the particles.

[0056] As the method using the inertial force, for example, an impactor type in which a vortex of air is generated by providing a guide vane or the like in the inside of a classification device, and coarse particles are removed when a raw material powder, which obtains power due to the air flow, is bent into a curve; a semi-free vortex centrifugal type in which centrifugal force is applied to a raw material powder and the raw material powder is classified; a Coanda type using a Coanda effect; and the like can be exemplified. In addition, as the classification device using the inertial force, a cascade impactor, a viable impactor, an Aerofine Classifier, an Eddy Classifier, an Elbow-Jet, a Hyperplex, a Coanda block, and the like can be exemplified.

[0057] As a method utilizing centrifugal force, for example, a method utilizing a vortex-like gas flow can be exemplified. As a device, a free vortex type and a forced vortex type can be exemplified. The free vortex type device can be exemplified by: a cyclone using no guide vane, a multi-stage cyclone, a Turboplex Classifier which promotes coagulation elimination by secondary air, a Dispersion separator which is provided with a guide vane and improves classification accuracy, a Micro-Spin, a Micro-cut, and the like. The forced vortex type is a device in which a rotating body inside the device causes centrifugal force to act on particles, and further, classification accuracy is improved by generating another gas flow inside the device, and can be exemplified by: a Turbo classifier, a Donaselec, and the like.

[0058] In the production method according to the present embodiment, from the viewpoints of production efficiency and classification accuracy, it is preferable to utilize a gas flow classification utilizing inertial force, and more preferable to include a step of classifying the raw material powder by a gas flow classification utilizing a wall-attachment effect. In addition, from the viewpoint of classification accuracy, the gas flow temperature is preferably less than 150°C, more preferably 40 to 130°C, and further preferably 60 to 120°C.

[0059] The production method of the silicon dioxide powder according to the present embodiment can have, for example, the following steps.

[0060] (i) a step of crushing and classifying an ore as necessary to obtain a coarse raw material powder;

[0061] (ii) a step of supplying the coarse raw material powder to a high-temperature flame in a reaction vessel to produce a raw material powder (a fused powder);

[0062] (iii) a step of classifying the raw material powder by a gas flow classification utilizing a wall-attachment effect at a gas flow temperature of less than 150°C to obtain a silicon dioxide powder having a D50 of 2.0 μm or less and a maximum particle diameter (D max ) of 5.0 μm or less as measured using a particle size measuring instrument according to the above method.

[0063] <Step (i)>

[0064] The raw material used in step (i) is preferably a high-purity (for example, a purity of 95% or more) raw material. As the raw material, metallic silicon, silica, and the like can be exemplified. These can be used alone as one kind or together as two or more kinds. Among them, it is more preferable to contain metallic silicon. The coarse raw material powder having a desired particle diameter is produced by crushing using a crusher such as a vibration mill or a ball mill. In addition, the D50 of the coarse raw material powder is preferably 5 to 40 μm, and more preferably 5 to 20 μm, from the viewpoints of operability, oxidation, and spheroidization.

[0065] <Step (ii)>

[0066] In step (ii), the raw material powder obtained in step (i) is injected into a high-temperature flame formed using a combustible gas and an auxiliary combustible gas using a burner, and is subjected to melt-spheroidization at a temperature of 1,600°C or higher, for example, in the case of silicon dioxide (quartz), and is classified and repaired while being cooled to obtain a spheroidized raw material powder (melted powder). In the case of metallic silicon, a slurry of the metal powder is supplied to a high-temperature flame formed using a combustible gas and an auxiliary combustible gas in a manufacturing furnace at a temperature of 2,400°C or higher, and the metal powder is vaporized and oxidized in the flame to obtain a raw material powder. In step (ii), the D50 of the raw material powder is preferably 0.2 to 2.0 μm, and more preferably 0.2 to 1.5 μm.

[0067] As the combustible gas, a hydrocarbon gas such as acetylene, ethylene, propane, butane, or methane; a gaseous fuel such as LPG, LNG, or hydrogen; or a liquid fuel such as lamp oil or heavy oil can be used. As the auxiliary combustible gas, oxygen, oxygen-enriched cooling gas, or air can be used.

[0068] In step (ii), the D50 of the raw material powder can also be adjusted by adjusting the powder supply amount, the powder temperature, the temperature of the combustible gas, the temperature of the auxiliary combustible gas, or the like.

[0069] <Step (iii)>

[0070] In step (iii), the raw material powder obtained in step (ii) is subjected to classification by gas flow using the wall-attachment effect at a gas flow temperature of less than 150°C to obtain a silicon dioxide powder having a D50 of 2.0 μm or less and a maximum particle diameter (D max ) of 5.0 μm or less as measured using the above method using a particle size measuring instrument.

[0071] As described above, the gas flow temperature is more preferably 40 to 130°C, and further preferably 60 to 120°C. The type of gas used in the gas flow can be any one of air, oxygen, nitrogen, helium, argon, carbon dioxide, or the like. The volume-based cumulative diameter (D50) of the silicon dioxide powder is set to 2.0 μm or less, and can be adjusted by introducing nitrogen from the viewpoint of making it difficult to agglomerate. The flow rate of the gas flow is preferably less than 80 m / s at the inlet of the wall-attachment block, more preferably 30 to 75 m / s, and further preferably 35 to 50 m / s. By satisfying these conditions, abrasion due to friction with the device is suppressed, and the dispersibility of the particles in the gas flow is further improved, and the wall-attachment effect is easily improved.

[0072] [Resin composition]

[0073] The resin composition according to the present application contains the above-described silicon dioxide powder and a resin.

[0074] The content of the silica powder in the resin composition is not particularly limited and can be appropriately adjusted according to the purpose. From the viewpoint of heat resistance, coefficient of thermal expansion, and the like, the ratio of the silica powder in the resin composition is preferably 40 to 90% by mass, more preferably 70 to 90% by mass, with respect to the total mass of the resin composition. The silica powder involved in the present application is excellent in dispersibility in a resin because the D50 is 2.0 μm or less and the maximum particle diameter (D max ) measured by the particle size measuring instrument according to the above method is 5.0 μm or less. Such a resin composition can be suitably used as a semiconductor sealing material, a substrate for semiconductor packaging.

[0075] (resin)

[0076] As the resin, a thermosetting resin is preferred. As the thermosetting resin, there is no particular limitation as long as it is a thermosetting resin generally used in the field of semiconductor sealing materials. For example, epoxy resins; silicone resins; phenol resins; melamine resins; urea resins; unsaturated polyester resins; fluororesins; polyimide resins, polyamide-imide resins, polyether-imide resins, and other polyimide-based resins; polybutylene terephthalate resins, polyethylene terephthalate resins, and other polyester-based resins; polyphenylene sulfide resins; wholly aromatic polyester resins; polysulfone resins; liquid crystal polymer resins; polyether sulfone resins; polycarbonate resins; maleimide-modified resins; ABS resins, AAS resins (acrylonitrile-acrylic rubber-styrene resins), AES resins (acrylonitrile-ethylene-propylene-diene rubber-styrene resins), and the like can be exemplified. These can be used alone as one kind or in combination with two or more kinds. Among them, an epoxy resin is more preferred.

[0077] As the epoxy resin, there is no particular limitation, and for example, phenol novolac-type epoxy resins, o-cresol novolac-type epoxy resins, epoxy resins obtained by epoxidizing phenol novolac resins of phenols and aldehydes, epoxy propylene oxide-type epoxy resins of bisphenol A, bisphenol F, and bisphenol S, epoxy propylene acid epoxy resins (bisphenol-type epoxy resins) obtained by the reaction of a polybasic acid such as phthalic acid or dimer acid with an epichlorohydrin, linear aliphatic epoxy resins, alicyclic epoxy resins, heterocyclic epoxy resins, alkyl-modified multifunctional epoxy resins, β-naphthol novolac-type epoxy resins, 1,6-dihydroxynaphthalene-type epoxy resins, 2,7-dihydroxynaphthalene-type epoxy resins, bisphenol-type epoxy resins, epoxy resins in which halogen such as bromine is introduced for further imparting flame retardancy, and the like can be exemplified. These can be used alone as one kind or in combination with two or more kinds. Among them, an epoxy resin containing at least one selected from the group consisting of bisphenol A-type epoxy resins, bisphenol F-type epoxy resins, and alicyclic epoxy resins is more preferred.

[0078] (curing agent)

[0079] When the epoxy resin is contained as the resin, the resin composition preferably further contains a curing agent. As the curing agent, for example, a phenol-formaldehyde novolac resin obtained by reacting one or a mixture of two or more selected from the group consisting of phenol, cresol, xylenol, resorcinol, chlorophenol, t-butylphenol, nonylphenol, isopropylphenol, octylphenol and the like with formaldehyde, paraformaldehyde or p-xylene in the presence of an oxidation catalyst, a poly-p-hydroxystyrene resin, a bisphenol compound such as bisphenol A, bisphenol S, a trifunctional phenol such as pyrogallol, m-phenylenetriol, a maleic anhydride, a phthalic anhydride, a pyromellitic anhydride, m-phenylenediamine, diaminodiphenylmethane, an aromatic amine such as diaminodiphenylsulfone, and the like can be exemplified.

[0080] The content of the curing agent is preferably adjusted so that the active hydrogen equivalent (or anhydride equivalent) of the curing agent becomes 0.01 to 1.25 per epoxy 1 equivalent of the epoxy resin.

[0081] (Other additives)

[0082] Within a range not impairing the effects of the present application, a curing accelerator, a release agent, a coupling agent, a colorant and the like can be incorporated in the resin composition.

[0083] As the curing accelerator, there is no particular limitation, and 1,8-diazabicyclo(5,4,0)undec-7-ene, triphenylphosphine, benzyldimethylamine, 2-methylimidazole and the like can be exemplified.

[0084] As the release agent, natural waxes, synthetic waxes, metal salts of straight-chain fatty acids, amides, esters, paraffin wax and the like can be exemplified.

[0085] As the coupling agent, a silane coupling agent can be exemplified. As the silane coupling agent, an epoxy silane such as γ-glycidoxypropyltrimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane and the like; an amino silane such as aminopropyltriethoxysilane, ureidopropyltriethoxysilane, N-phenylaminopropyltrimethoxysilane and the like; a hydrophobic silane compound such as phenyltrimethoxysilane, methyltrimethoxysilane, octadecyltrimethoxysilane and the like; a mercapto silane and the like can be exemplified.

[0086] One embodiment of the resin composition according to the present application is a resin composition containing the silica powder according to the present application and a bisphenol F type epoxy resin, and having a maximum particle size (D max ) of 5.0 μm or less as measured by a particle size measuring instrument under the following conditions. The maximum particle size (D max ) can be 4.0 μm.

[0087] (Measurement method)

[0088] A resin composition was prepared by adding 67 parts by mass of silica powder to 100 parts by mass of a bisphenol F-type liquid epoxy resin, and mixing the mixture using a self-rotation and revolution mixer at a temperature of 30°C and a rotation speed of 2000 rpm for 3 minutes of self-rotation and 1 minute of revolution. The dispersion of the silica powder in the epoxy resin was evaluated using a particle size measuring instrument having a width of 90 mm, a length of 240 mm, and a maximum depth of 100 μm, according to JIS K 5600-2-5, using a distribution chart method, and the maximum particle diameter (D max ) was measured. In addition, the same evaluation was performed five times, and the average value was used.

[0089] Method for producing a resin composition

[0090] The method for producing a resin composition is not particularly limited, and the resin composition can be produced by stirring, dissolving, mixing, and dispersing predetermined amounts of the materials. The device for mixing, stirring, and dispersing the mixture is not particularly limited, and a kneader, a three-roll mill, a ball mill, a planetary mixer, or the like having a stirring and heating device can be used. These devices can also be used in combination as appropriate.

[0091] [Semiconductor sealing material]

[0092] The semiconductor sealing material according to the present application is produced using the resin composition according to the present application.

[0093] Specifically, first, the resin composition is heated using a roll or an extruder, and the mixture is kneaded. The kneaded product is then extended into a sheet shape and cooled. The semiconductor sealing material, which is a pulverized product of the resin composition, can be obtained by pulverizing the kneaded product, or by extruding the kneaded product into a linear shape and cutting the product after cooling. The pulverized product can also be formed into a flat plate shape, a pellet shape, or the like.

[0094] As a method for sealing a semiconductor using the semiconductor sealing material according to the present application, a conventionally known method such as transfer molding or compression molding can be used, for example.

[0095] As a method for transfer molding, for example, a method in which a flat plate-shaped semiconductor sealing material is filled into a groove provided in a mold of a transfer molding machine, the material is melted by heating, the material is further heated and solidified by pressure using a plunger, and the sealing material is solidified can be used.

[0096] As a method for compression molding, for example, a method in which a pellet-shaped or flat plate-shaped sealing material is directly disposed in a mold, the material is melted, and a chip or a wafer to be joined is immersed in the melted resin and is solidified by heating can be used.

[0097] Example

[0098] The following examples illustrate the present application in detail, but the present application is not limited to the following description.

[0099] [Examples 1 to 4 and Comparative Examples 1 to 7]

[0100] (Manufacture of raw material powder: steps (i) to (ii))

[0101] A burner of triple coiled tube structure assembled in the order of combustible gas supply tube, combustion-supporting gas supply tube, and metal silicon powder slurry supply tube from the outermost was provided at the top of a manufacturing furnace, and a device configured using the lower part of the manufacturing furnace connected to a classification and collection system such as a cyclone (generated particles are sucked by a blower and collected to a bag filter) was used to manufacture the raw material powder. In addition, three peripheral burners that form a peripheral flame were further provided around the burner. LPG at 7 Nm 3 / hr was supplied from the combustible gas supply tube, and oxygen at 12 Nm 3 / hr was supplied from the combustion-supporting gas supply tube, and a high-temperature flame was formed inside the manufacturing furnace. Metal silicon powder (average particle diameter (D50): 10 μm) was dispersed in methanol, and the prepared metal silicon slurry was supplied to the flame from the metal silicon powder slurry supply tube using a slurry pump, and the generated raw material powder (spherical silica powder) was collected using a cyclone or a bag filter while the powder temperature was 110°C to 200°C. In addition, the particle diameter and specific surface area of the raw material powder were prepared by adjusting the slurry concentration to control the metal silicon concentration inside the furnace. Through these operations, raw material powders having D50 of 0.5 μm, 0.7 μm, 1.0 μm, 1.5 μm, 1.9 μm, and 2.6 μm were obtained.

[0102] (Classification of raw material powder: step (iii))

[0103] Each of the raw material powders obtained above was classified under the conditions shown in Table 1 to obtain the silica powder of each example. The classification operation was performed using a blower to feed the raw material powder to an air flow classifier (MATSUBO Corporation, trade name "Elbow-Jet Classifier") having an attached wall block structure, and then collected using a bag filter. The gas used in the air flow used nitrogen or air (dew point temperature: -5°C). In addition, the gas temperature of the air flow and the flow rate of the attached wall part are shown in Table 1.

[0104] (Measurement method of particle size measuring instrument)

[0105] The maximum particle diameter (D max ) of the silica powder obtained in each example was measured under the following conditions.

[0106] A resin composition was prepared by adding 67 parts by mass of silica powder to 100 parts by mass of a bisphenol F type liquid epoxy resin (manufactured by Mitsubishi Chemical Corporation, product name "807", viscosity: 3000 to 4500 mPa-s, epoxy equivalent: 160 to 175 g / eq.) and mixing the mixture using a self-rotation and revolution mixer (manufactured by THINKY Corporation, product name "ARE-310") at a temperature of 30°C and a rotation speed of 2000 rpm for 3 minutes of self-rotation and 1 minute of revolution. The obtained resin composition was evaluated for the dispersibility of the above-described silica powder in the above-described epoxy resin using a particle size measuring instrument having a width of 90 mm, a length of 240 mm, and a maximum depth of 100 μm according to JIS K 5600-2-5 using a distribution chart method, and the maximum particle diameter (D max ) was measured. In addition, the same evaluation was performed five times, and the average value was used. The results are shown in Table 1.

[0107] (Measurement of volume-based cumulative diameters (D50, D90, and D100))

[0108] For the silica powder obtained in each example, a particle size distribution measuring instrument (manufactured by Beckman Coulter, Inc., product name "LS-13 320XR") was used, water (refractive index: 1.33) was used as a solvent, and dispersion treatment was performed using an ultrasonic generator (manufactured by SONICS MATERIALS INC, product name "VC-505") for 2 minutes as a pretreatment, and then, a frequency particle size distribution on a volume basis was measured using a laser diffraction light scattering method. In addition, the value of the volume-based frequency of D90, D100, and D90 was substituted into the above-described formula (1) and calculated. These results are shown in Table 1.

[0109] (Measurement of specific surface area (BET))

[0110] For the silica powder obtained in each example, 1.0 g of the silica powder was weighed and put into a cell for measurement, and after pretreatment, the BET specific surface area value was measured using nitrogen. A "Macsorb HM model-1208" manufactured by MACSORB Corporation was used as a measuring instrument. The specific surface area was measured under the following conditions. The results are shown in Table 1.

[0111] Degassing temperature: 300°C

[0112] Degassing time: 18 minutes

[0113] Cooling time: 4 minutes.

[0114] [Table 1]

[0115]

[0116] As shown in Table 1, the D50 of the silica powder of Examples 1 to 4 was 2.0 μm or less and the maximum particle size (D max ) measured by the particle size measuring instrument was 5.0 μm or less. That is, a silica powder which did not easily agglomerate even when mixed with a resin and which was easily dispersed was obtained. Furthermore, it was found that such a silica powder became easily obtainable by classifying the raw material particles at a low gas temperature and at a low flow rate using nitrogen. Furthermore, from the results of Comparative Examples 1 to 7, it was found that when no classification treatment was performed and when classification treatment was performed in air, the silica powder easily agglomerated in the resin.

[0117] [Industrial Applicability]

[0118] As described above, the silica powder according to the present application has the following characteristics: the D50 is 2.0 μm or less and agglomeration does not easily occur, the handling properties are good, and dispersion is easy when mixed with a resin. A resin composition containing such a silica powder can be suitably used as a semiconductor sealing material.

Claims

1. A silica powder having a volumetric cumulative diameter D50 of less than 2.0 μm, and a maximum particle size D measured by a particle size analyzer according to the following method. max Below 5.0 μm; The determination method is as follows: A resin composition was prepared by adding 67 parts by weight of silica powder to 100 parts by weight of bisphenol F type liquid epoxy resin, and mixing the mixture using a rotary mixer at 30°C and 2000 rpm for 3 minutes of rotation and 1 minute of revolution. The dispersion of the silica powder in the epoxy resin was evaluated using a particle size analyzer with a width of 90 mm, a length of 240 mm, and a maximum depth of 100 μm, according to JIS K 5600-2-5, and the distribution map method was used to determine the maximum particle size D. max In addition, the same evaluation was conducted 5 times, and the average value was used. The difference between the volume reference frequency of the volume reference cumulative diameter D90 calculated by Equation 1 and the volume reference cumulative diameter D100 and the volume reference cumulative diameter D90 is 1.0~3.

0. (volume reference frequency of cumulative diameter D90) / (cumulative diameter D100-cumulative diameter D90)…(1).

2. The silica powder according to claim 1, wherein, The cumulative diameter D90 based on volume is less than 2.5 μm.

3. The silica powder according to claim 1 or 2, wherein, The volumetric cumulative diameter D100 is less than 4.7 μm.

4. The silica powder according to claim 1 or 2, wherein, The specific surface area determined by the BET method is 2~15m². 2 / g.

5. The silica powder according to claim 3, wherein, The specific surface area determined by the BET method is 2~15m². 2 / g.

6. A resin composition comprising the silica powder and resin as described in any one of claims 1 to 5.

7. The resin composition according to claim 6, wherein, The resin comprises a thermosetting resin.

8. A semiconductor sealing material made using the resin composition of claim 6 or 7.

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