Metal oxide particle material, method for producing same, slurry composition, resin composition, and filler for sealing material for semiconductor encapsulation

Abstract

The present invention addresses the problem of providing a metal oxide particle material which has high filling properties in a resin material and which contains a small amount of hollow particles and coarse particles. As a result, when a metal oxide particle material having a D50 range and an upper limit value of the content of coarse particles and hollow particles within an appropriate range is prepared and actually studied as a filler for a sealing material for semiconductor packaging, it was found that the metal oxide particle material has high performance and has excellent performance. Thus, the following invention is completed. Specifically disclosed is a metal oxide particle material which comprises a metal oxide as a main component, and which has a D50 of 1.0-5.0 [mu] m as measured by laser diffraction particle size distribution, a specific surface area of 1.0-30 m2 / g, a content of coarse particles having a particle diameter of 5 [mu] m or more of 300 ppm or less, and a content of hollow particles having a particle diameter of 5 [mu] m or more of 4000 particles / 10 mg or less. When the resin material is filled with the resin composition at a solid content concentration of 60 mass%, the viscosity of the resin composition is 170 Pas or less (when the shear rate is 1 s-1).

Description

Technical Field

[0001] This invention relates to metal oxide particle materials, methods for manufacturing the same, slurry compositions, resin compositions, and fillers for sealing materials used in semiconductor packaging. Background Technology

[0002] To protect semiconductor IC chips from dust and moisture in the air, sealing materials are used to seal the IC chips, creating semiconductor packages. Sealing materials are primarily composed of heat-resistant... A resin composition consisting of resins with high chemical resistance and metal oxide particles such as silica with low coefficient of thermal expansion, alumina, magnesium oxide, and zinc oxide with high thermal conductivity.

[0003] Depending on the application and performance requirements, there are various methods for manufacturing semiconductor packages. High-performance / miniature packages for mobile devices are mostly manufactured using FOWLP and FOPLP technologies.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2021-161008 Summary of the Invention

[0005] In FOWLP technology, the structures of the finished packages are very similar, but the manufacturing processes vary significantly depending on the packaging development company. These differences in manufacturing processes greatly affect the performance of the finished package.

[0006] Starting with the wafer-level carrier, the process can be broadly divided into the Chip First method, where the silicon chip is mounted first, and the Chip Last method, where the rewiring structure is formed first. The Chip First process can be further subdivided into Face-Up and Face-Down methods, where the silicon chip is mounted on the carrier with the circuit side facing up.

[0007] Among the various FOWLP process methods, there is a grinding step to smooth the surface of the semiconductor package containing the sealing material after the IC chip is sealed. If hollow particles are present in the sealing material, or if voids are created in the sealing material due to air bubbles, depressions will form on the ground package surface, leading to reduced yield due to decreased surface smoothness and deteriorated appearance.

[0008] In particular, in processes such as Face-Up packaging where a redistribution layer is formed on the surface of a semiconductor package after surface grinding, the presence of hollow particles in the sealing material can lead to the formation of copper wiring in the recesses of the package surface. In this state, if the package expands / contracts due to temperature changes, the presence of these hollow spaces can cause the copper wiring to bend and break. Without these hollow spaces, the copper wiring is surrounded by the sealing material, preventing bending even during expansion / contraction. Furthermore, while copper wiring has historically been rigid and less prone to bending due to its large linewidth exceeding 10 μm, the rigidity of copper wiring decreases as packaging performance and miniaturization increase, thus reducing the content of hollow particles in the sealing material is crucial.

[0009] Regarding packaging for servers, the structure and manufacturing methods differ from those described above. Sometimes, the package is mounted in a flip-chip structure on an interposer, and then the entire package is sealed. Furthermore, in high-end products, there are manufacturing methods that involve two processes: bottom filling of a narrow gap under the chip and overmolding to protect the entire chip. However, there are also methods that completely seal both the underside and topside of the chip. High fluidity is particularly important for complete sealing. These packaging forms also include surface polishing processes to smooth the package surface, and the filler used in the sealing material also strongly requires a low content of hollow particles, just as strongly as described above.

[0010] To meet the above-mentioned requirements, with the miniaturization and micro-wiring of semiconductor packaging, it is also necessary to precisely remove solid coarse particles, and the size of the coarse particles to be removed is gradually decreasing. However, from the viewpoint of the flowability of the resin composition obtained by mixing filler and resin, spherical particles with a large number of diameters are preferred.

[0011] Therefore, for the filler of the sealing material for encapsulation as described above, it is required to have all the characteristics of large diameter, precise removal of coarse particles, high filling capacity in the resin, and low content of hollow particles.

[0012] Previously, as mentioned above, the sealing material used for packaging used metal oxide particles with solid particles (coarse particles) of D50 size of 2μm to 5μm removed as fillers. However, since the hollow particles were not removed, when the line width of the copper wiring was less than 5μm, the yield during packaging production was significantly reduced due to the risk of wire breakage and the deterioration of the appearance.

[0013] Although metal oxide particles with solid particles (coarse particles) of D50 size of 5-9 μm and above are widely used and can be highly filled into resin due to their large D50, the presence of coarse particles of 5-10 μm size prevents them from filling narrow gaps. The presence of hollow particles of 5-10 μm size also poses a risk of wire breakage, deterioration of appearance, and lower yield during encapsulation production.

[0014] As a technique for removing hollow particles, Patent Document 1 discloses a silica particle and its manufacturing method, wherein the silica particle has a D50 of 100nm to 200nm and a specific surface area of ​​30m². 2 The number of hollow particles with a diameter of 2μm or larger is less than 1000 per 0.1g. However, due to the small D50 and high viscosity when mixed with resin, the filler in the resin is difficult to fill to a high degree, and it cannot show the low coefficient of thermal expansion and high rigidity required for the encapsulation.

[0015] Furthermore, while synthetic silica produced via wet synthesis contains almost no hollow particles, its particle size distribution becomes extremely sharp, making it difficult to improve its filling properties in resins. To adjust the particle size distribution, mixing wet-synthetic silica particles of different sizes can be considered; however, in the case of wet synthesis, the high amount of hydroxyl groups on the particle surface inherently hinders its filling properties in resins. Although a firing process can be used to reduce the amount of surface hydroxyl groups, this results in particle fusion. A crushing process can mitigate particle fusion to some extent, but this is a lengthy and very expensive process.

[0016] The present invention was made in view of the above-mentioned actual situation, and the problem to be solved is to provide a metal oxide particle material with high filling capacity in resin material and low content of hollow particles and coarse particles, a method for manufacturing the same, a slurry composition, a resin composition, and a filler for sealing materials for semiconductor packaging.

[0017] The inventors conducted in-depth research and found that when a metal oxide particle material with an appropriate range of D50 and upper limits of coarse and hollow particle content was prepared and used as a filler for sealing materials in semiconductor packaging, it exhibited high performance, thus completing the following invention.

[0018] The metal oxide particle material of this invention, which solves the above-mentioned problems, is mainly composed of metal oxides, with a D50 of 1.0 μm to 5.0 μm determined by laser diffraction particle size distribution, and a specific surface area of ​​1.0 m². 2 / g~30m 2 / g, the content of coarse particles with a particle size of 5μm or larger is less than 300ppm, the content of hollow particles with a particle size of 5μm or larger is less than 4000 particles / 10mg, and the viscosity of the resin composition when filled into the resin material at a solid content concentration of 60% by mass is 170Pa. less than s (shear rate is 1s) -1 hour).

[0019] Furthermore, the method for manufacturing the metal oxide particle material of the present invention, which solves the above-mentioned problems, is a method for manufacturing the metal oxide particle material of the present invention, and has the following characteristics:

[0020] The manufacturing process involves passing raw material particles, primarily composed of metals constituting the aforementioned metal oxide particle material, through a high-temperature oxidizing atmosphere to induce combustion, followed by cooling, thereby producing raw material metal oxide particle materials with a D50 of 1.0 μm to 5.0 μm; and

[0021] The grading process categorizes the above-mentioned raw material metal oxide particles to a content of less than 300 ppm for coarse particles with a particle size of 5 μm or larger, and less than 4000 hollow particles with a particle size of 5 μm or larger per 10 mg.

[0022] The metal oxide particle material of the present invention exhibits excellent flow characteristics, such as impregnation into narrow gaps, when dispersed in a resin material to form a resin composition. Furthermore, it can eliminate the risk of wire breakage in packages with copper wiring widths of 10 μm or less, and in server packages. The deterioration of appearance makes it particularly useful as a filler for semiconductor sealing materials. Detailed Implementation

[0023] The metal oxide particle material, its manufacturing method, slurry composition, resin composition, and filler for sealing materials for semiconductor packaging of the present invention will be described in detail below according to the embodiments. The metal oxide particle material of this embodiment can be dispersed in a resin material to form a resin composition, or dispersed in a liquid dispersion medium to form a slurry composition. It is particularly suitable as a filler for sealing materials for semiconductor packaging.

[0024] (Metal oxide particle materials and fillers for sealing materials used in semiconductor packaging)

[0025] The metal oxide particle material of this embodiment can be appropriately used directly as a filler for sealing materials used in semiconductor packaging. As a semiconductor, products manufactured using FOWLP or FOPLP technologies are preferred.

[0026] The metal oxide particle material of this embodiment is mainly composed of metal oxides. "Mainly composed of metal oxides" means that, based on the mass of the metal oxide particle material, it consists of 50% or more metal oxides, preferably 60% or more, 70% or more, 80% or more, 90% or more, or 95% or more. It is determined whether each type of metal oxide particle material is mainly composed of metal oxides. Therefore, in the case where there are particle materials mainly composed of metal oxides and particle materials not mainly composed of metal oxides, it is a mixture of the metal oxide particle material of this embodiment and other particle materials. Examples of metal oxides include oxides containing one or more of Si, Al, Zr, Ti, etc. The metal oxide can be amorphous, crystalline, or a mixture of both.

[0027] The D50 of metal oxide particle materials, determined by laser diffraction particle size distribution, ranges from 1.0 μm to 5.0 μm. Examples of lower limits for D50 include 1.2 μm, 1.4 μm, 1.6 μm, 1.8 μm, 2.0 μm, and 2.2 μm, while examples of upper limits include 4.8 μm, 4.6 μm, 4.4 μm, 4.2 μm, 4.0 μm, 3.8 μm, 3.6 μm, and 3.4 μm. These upper and lower limits can be combined arbitrarily. D50 is a value measured by laser diffraction particle size distribution, starting from the smallest particle size and reaching 50% of the volume reference particle size. That is, D100 represents 100% of the particle size, starting from the smallest particle size. It should be noted that the values ​​of D50 and D100 are calculated as values ​​within the measurement limit range determined by laser diffraction particle size distribution. In reality, there are coarse and micro particles that cannot be detected in laser diffraction particle size distribution measurements. Therefore, the existence of particles with particle sizes larger than D100 is not contradictory.

[0028] The viscosity of the resin composition when filled with a solid content of 60% by mass into the resin material is 170 Pa. less than s (shear rate is 1s) -1 As the resin material, an epoxy resin of 1:1 mixture of bisphenol A type epoxy resin and bisphenol F type epoxy resin is used (e.g., Nippon Steel Chemical & Material Co., Ltd., ZX-1059).

[0029] The D50 value can be controlled by adjusting the manufacturing conditions of the metal oxide particles. Furthermore, it can be adjusted through grading or by adding particles with different particle size distributions. For grading, centrifugal separation, such as using a cyclone separator, can be used as an example. Grading can also be performed on the particles to be added.

[0030] The linseed oil absorption of the metal oxide particle material is preferably 2.7 g / 15 g or less, more preferably 2.5 g / 15 g or less, and even more preferably 2.3 g / 15 g or less. The linseed oil absorption is calculated as follows: linseed oil is added dropwise relative to 15 g of metal oxide particle material, and the amount of linseed oil added (g) is determined by visually confirming the fluidization, and calculated as the amount of linseed oil added (g) ÷ the mass of the particle material (15 g).

[0031] In metal oxide particle materials, the content of coarse particles with a particle size of 5 μm or larger is 300 ppm or less, or can be set to 200 ppm or less, 100 ppm or less, 50 ppm or less, 30 ppm or less, etc. Furthermore, the particle size of coarse particles can also be 4.5 μm, 4 μm, etc. The removal of coarse particles can be carried out through a classification operation as described later, for example, using a cyclone separator.

[0032] Specific surface area is 1.0 m² 2 / g~30m 2 / g. As a lower limit for specific surface area, 1.1m³ can be exemplified. 2 / g, 1.2m 2 / g, 1.4m 2 / g, 1.6m 2 / g, 1.8m 2 / g, 2.0m 2 / g, 2.5m 2 / g, 3.0m 2 Approximately / g, as an upper limit, 27.5m can be exemplified. 2 / g, 25m 2 / g, 22.5m 2 / g, 20m 2 / g, 17.5m 2 / g, 15m 2 / g, 12.5m 2 / g, 10m 2 / g, 7.5m 2 / g, 5.0m 2 / g, 4.5m 2 Approximately / g. The specific surface area is a value measured using the BET method with nitrogen. A smaller specific surface area results in lower viscosity when used in slurry compositions, etc., which is therefore preferred. There are no particular limitations on the method for controlling the specific surface area, but the specific surface area can be reduced by implementing methods that minimize the amount of microparticles during the synthesis of metal oxide particle materials, or by controlling the residence time in the classifier to a longer duration during classification.

[0033] Regarding the number of hollow particles, the limit is 4000 particles / 10mg for hollow particles larger than 5μm. This upper limit can be 3500, 3000, 2500, 2000, 1500, 1000, 750, 500, 250, 200, 150, 100, 50, 40, or 30 particles / 10mg. The number of hollow particles can also be calculated based on the number of hollow particles larger than 2μm, and the above values ​​are used for specification. As will be discussed later, the range of particle sizes for solid and hollow particles can be defined using other principles, therefore the lower limit of the particle size can be set to other values.

[0034] The number of hollow particles can be reduced by using a filtration method, utilizing the difference in specific gravity of the liquid for grading. Details will be provided in the manufacturing method section below. It should be noted that the upper limit of 4000 hollow particles / 10mg is a very small value compared to the upper limit of 300ppm for coarse particles.

[0035] The number of hollow particles was determined by dispersing the metal oxide particle material in a liquid and counting the number of hollow particles using an image analysis particle size analyzer. The ratio of the refractive index ns of the liquid to the refractive index nf of the metal oxide particle material (ns / nf) was determined to be 0.98–1.02.

[0036] When a solid that is insoluble in a liquid is dispersed, if the refractive index of the solid is approximately the same as that of the liquid, the solid is difficult to distinguish visually within the liquid. Therefore, even though the solid has been dispersed, the liquid is still perceived as transparent.

[0037] In contrast, hollow particles in metal oxide particle materials, due to their internal voids, can be observed optically based on the difference in refractive index between them and the liquid. Therefore, while solid particles become transparent and difficult to distinguish visually, hollow particles become particularly distinguishable, thus allowing for the counting of hollow particles.

[0038] Alkali metals and alkaline earth metals are preferably present in amounts of 100 ppm, 80 ppm or less, 50 ppm or less, and 30 ppm or less. This can be achieved by refining the materials used in manufacturing the metal oxide particle materials. Since alkali metals and alkaline earth metals are prone to oxidation and may leach or even precipitate as ions, their application in sealing materials for semiconductor devices could potentially cause unintended effects on these devices. For example, if the conductivity (EC) of the water extract is assumed to be 10 μS / cm or less, it is preferably 10 μS / cm or less. To reduce this value, a low content of alkali metals and alkaline earth metals is preferred, hence the above-mentioned content range is set. The EC is measured as follows: Metal oxide particles are suspended in ion-exchanged water (conductivity 1 μS / cm or less) and added to a pressure vessel as a 10% slurry. The mixture is then shaken at room temperature for 30 minutes. The conductivity of the supernatant after centrifugation is then measured using an ES-51 conductivity meter (EC meter) manufactured by Horiba Corporation. The EC value is the conductivity at this point.

[0039] The metal oxide particle material of this embodiment is preferably surface-treated with a surface treatment agent such as a silane compound or a silazane compound. The silane compound or silazane compound is not particularly limited; silane compounds or silazane compounds with appropriate functional groups can be selected for surface treatment as needed. Alternatively, a combination of two or more silane compounds and silazane compounds can be selected for surface treatment.

[0040] In this embodiment, the alpha ray generation amount of the metal oxide particle material is preferably 0.001 c / cm. 2 Below h. In particular, uranium and thorium used as alpha ray sources are preferably below 3 ppb (more preferably below 1 ppb).

[0041] (Manufacturing method of metal oxide particle materials)

[0042] The method for manufacturing metal oxide particle materials according to this embodiment includes a manufacturing process, a grading process, and other processes adopted as needed. The method for manufacturing metal oxide particle materials according to this embodiment can appropriately manufacture the metal oxide particle materials of this embodiment described above.

[0043] Manufacturing process

[0044] The manufacturing process involves burning raw material particles to produce raw metal oxide particles. The volume average particle size of the produced raw material particles is 1 μm to 5 μm. This volume average particle size range is the same as that of the metal oxide particles to be manufactured. Although a classification process to remove coarse particles is performed later, it is preferable to remove as few coarse particles as possible, thus achieving a volume average particle size equivalent to that of the manufactured metal oxide particles.

[0045] This process is known as the VMC method, which yields raw metal oxide particles that readily exhibit high sphericity, density, and excellent electrical properties. The raw material can be selected based on the type of metal oxide contained within the manufactured metal oxide particles. For example, silicon is used when the metal oxide is silicon dioxide, aluminum when it is alumina, and zirconium when it is zirconium oxide. When the metal oxide contains multiple metal elements, the raw material particles contain the corresponding metal. In cases containing multiple metals, the particles can be a mixture of particles composed of various metals, or a single particle can contain two or more metal elements.

[0046] The VMC method is as follows: a combustible agent (hydrocarbon gas, etc.) is burned in an oxygen-containing atmosphere to form a chemical flame, which serves as a high-temperature atmosphere. A quantity of raw material particles sufficient to form a dust cloud is then introduced into this chemical flame, triggering deflagration to obtain the raw material metal oxide particles. An atmosphere with a temperature above 2000°C is preferred as the high-temperature atmosphere.

[0047] The operation of the VMC method is explained as follows. First, a container is filled with a gas containing oxygen as a reactant, forming a chemical flame within this gas. Next, raw material particles are introduced into this chemical flame, forming a dust cloud. The chemical flame then imparts heat to the surface of the raw material particles, raising the surface temperature of the metal components and causing the contained metal vapors to diffuse from the surface of the particles to the surrounding area. This vapor reacts with oxygen to ignite, producing a flame. The heat generated by the flame further promotes the vaporization of the raw material particles, and the resulting vapor mixes with oxygen, leading to a chain reaction of ignition propagation. Therefore, the smaller the particle size of the raw material, the larger its specific surface area and the higher its reactivity, thus reducing the energy required.

[0048] Through this chain-reaction ignition, the raw material particles themselves are destroyed and dispersed, promoting flame propagation. The gases generated after combustion naturally cool, forming a cloud of metals contained in the raw material particles. The resulting raw material metal oxide particles can be collected using bag filters, electrostatic precipitators, etc.

[0049] The VMC method utilizes the principle of dust explosion. According to the VMC method, a large quantity of raw material metal oxide particles can be obtained instantaneously. The resulting raw material metal oxide particles are approximately spherical in shape. By adjusting the particle size, amount, and flame temperature of the input raw material particles, the particle size distribution of the obtained raw material metal oxide particles can be adjusted. Furthermore, the raw material particles can be a single metal or particles composed of metal oxides (such as silicon dioxide) can be added. Simultaneously, by using metal oxide particles obtained through this method, the purity of the resulting raw material metal oxide particles can be maintained.

[0050] The raw material particles can also be surface-treated with silane compounds, silazane compounds, etc. There are no particular limitations on the types of silane compounds that can be used; the silane compounds used in the surface treatment process described later can also be used.

[0051] The raw material particles are burned by being introduced into a flame while dispersed in a carrier. The rate at which the raw material particles are introduced into the flame is not particularly limited. The carrier can be a gas such as nitrogen, argon, or air, or a liquid such as water or alcohol. There are no particular limitations on how the material is dispersed; however, if dispersed in a liquid, it is preferable to inject it into the flame as a mist. For example, based on the overall volume, it is preferable to include approximately 10% to 80% of the raw material particles.

[0052] As a flame, an oxidizing atmosphere is used. For example, a flame obtained by burning flammable gases such as LPG, ammonia, and hydrogen in an atmosphere containing excess oxygen can be cited. In addition, thermal plasma is also included in the flame.

[0053] Metallic raw material particles introduced into a flame are vaporized through combustion and rapidly cooled to become silica particles. The resulting silica particles are then recovered using methods such as bag filters.

[0054] Grading process

[0055] The grading process is a step of classifying the above-mentioned raw material metal oxide particles into a particle size distribution where the content of coarse particles is below the upper limit and the content of hollow particles with a particle size of 5 μm or larger is below the upper limit. The coarse particles consist of solid particles and hollow particles.

[0056] Grading operations include centrifugation in gases or solvents, separation by gravity in liquid phases, and methods using sieves in dry or wet conditions. Each grading operation is repeated until the target particle size distribution is achieved.

[0057] Centrifugation is a suitable method for removing solid particles from coarse particles. The solvent used for centrifugation is preferably of low viscosity. Examples include methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), and toluene. Solid coarse particles can be separated with high precision by centrifugation at a concentration of approximately 10% to 30% by mass (especially 15% to 25% by mass) dispersed in MEK. Wet centrifugation removes coarse particles by applying centrifugal force to the slurry, causing it to settle.

[0058] To separate coarse particles composed of hollow particles, it is preferable to separate the lighter hollow particles after dispersion in a liquid phase. Separation in the liquid phase is preferably performed by removing the hollow particles present in the supernatant after dispersion and allowing the mixture to stand or by applying centrifugal force (hollow particle separation step). The liquid used can be the same substance used in centrifugation. Furthermore, since solid particles in the coarse particle composition settle rapidly while hollow particles settle slowly or not at all, it is also possible to remove both coarse particles composed of solid and hollow particles by removing the supernatant along with the operation for removing the aforementioned coarse particles.

[0059] Furthermore, when using a filter for classification, the process is carried out in the state of a dispersion slurry dispersed in a solvent. It is preferable to perform the filter classification operation multiple times. When performing multiple times, it is preferable to perform the filter classification operation while changing from a filter with a large pore size to a filter with a small pore size.

[0060] Other processes

[0061] Surface treatment processes can be employed. Surface treatment processes can be performed before, during, or at any time during the application of grading processes to raw metal oxide particle materials manufactured through the manufacturing process.

[0062] The surface treatment process involves treating the raw metal oxide particle material with surface treatment agents such as silane compounds and silazane compounds. This introduces functional groups from the surface treatment agent or allows the surface treatment agent to adhere to the surface of the final manufactured metal oxide particle material.

[0063] Surface treatment is performed by bringing a surface treatment agent (in liquid or gaseous form) directly into contact with the surface of the particles, or by bringing the agent into contact with the particles while it is dissolved in a solvent. In surface treatment, heating may also be performed after the surface treatment agent has come into contact with the particles. The surface treatment process can also be carried out in the liquid phase during the grading process described above, where grading is performed in the liquid phase.

[0064] There is no particular limitation on the amount of surface treatment agent used for surface treatment. For example, when using substances that react with the surface of particles, such as silane compounds or silazane compounds, as surface treatment agents, the amount used can be selected based on the amount of OH groups present on the surface of the particles to be treated, such as 100%, 75%, 50%, 25%, etc. An excess amount exceeding 100% (120%, 150%, etc.) can also be selected. In this case, unreacted surface treatment agent remains on the surface of the particles.

[0065] As a silane compound, there is no particular limitation, and examples include silane compounds having phenyl, alkyl, vinyl, methacryloyl, epoxy, phenylamino, amino, styryl, etc.

[0066] (Resin composition)

[0067] The resin composition of this embodiment is obtained by dispersing the aforementioned metal oxide particle material in a resin material (which also includes a resin material precursor). The mixing ratio of the metal oxide particle material to the resin material is not particularly limited. Examples of resin materials are not particularly limited, such as epoxy resin, acrylic resin, and silicone resin. A resin material precursor prior to curing may also be used.

[0068] (Slurry composition)

[0069] The slurry composition of this embodiment is obtained by mixing the above-mentioned metal oxide particle material with a liquid dispersion medium (solvent, resin material precursor, etc.). The mixing ratio of the metal oxide particle material to the dispersion medium is not particularly limited. In addition to the above-mentioned resin material precursor, other dispersion media include alcohols such as MEK, MIBK, hexane, and isopropanol.

[0070] Example

[0071] The metal oxide particle material and its manufacturing method of the present invention will be described in detail below with reference to embodiments.

[0072] (Experimental Example 1)

[0073] After igniting raw material particles composed of metallic silicon in a high-temperature atmosphere and then cooling them, a particle size distribution (D50) of 2.0 μm and a specific surface area of ​​2.0 m² were obtained based on laser diffraction particle size distribution measurements. 2 / g of raw material metal oxide particles composed of silicon dioxide (manufacturing process).

[0074] The raw metal oxide particles were treated with a cyclone separator to remove coarse particles larger than 5 μm in diameter, reducing their concentration to below 300 ppm (grading process). After removing the coarse particles, 100 g of the resulting particle material was placed in a 500 mL plastic container, and 50 g of isopropanol was added as a solvent. The mixture was then dispersed for 5 minutes using a commercially available homogenizer to ensure uniform particle dispersion, thus preparing a slurry. The slurry was then allowed to stand for 1.2 hours, and the supernatant layer (95% of the depth, 1 cm from the surface) was removed using a dropper. Since the supernatant layer contains hollow particles concentrated due to the density difference between hollow and solid particles, these hollow particles were effectively removed (hollow particle separation step in the grading process).

[0075] The remaining portion after removing the supernatant layer was transferred to a metallic tray container and dried at 130°C for 8 hours using a quasi-explosion-proof dryer, resulting in 41g of metal oxide particle material. Then, to reduce the viscosity when mixed with the resin material, a surface treatment was performed using 3-methacryloyloxypropyltrimethoxysilane as a surface treatment agent (surface treatment step), thus preparing the test specimen for this experimental example.

[0076] (Experimental Example 2)

[0077] Except for omitting the hollow particle separation process, metal oxide particle materials were prepared using the same procedures as in Experimental Example 1, and used as the test specimens for this experiment.

[0078] (Experimental Example 3)

[0079] Except for omitting the hollow particle separation process and surface treatment process, metal oxide particle materials were prepared using the same operation as in Experimental Example 1, and used as the test specimens for this Experimental Example.

[0080] (Experimental Example 4)

[0081] Crushed silica was used as a raw material and spheroidized in a molten flame to obtain particles with a D50 of 3.5 μm and a specific surface area of ​​1.5 m². 2 / g particles, and remove coarse particles larger than 10μm according to the method of Experimental Example 1, and use the metal oxide particle material prepared therefrom as the test sample of this Experimental Example.

[0082] (Experimental Example 5)

[0083] Crushed silica was used as a raw material and spheroidized in a molten flame to obtain particles with a D50 of 5.0 μm and a specific surface area of ​​5.0 m². 2 / g particles, and remove coarse particles larger than 10μm according to the method of Experimental Example 1, and use the metal oxide particle material prepared therefrom as the test sample of this Experimental Example.

[0084] (Experimental Example 6)

[0085] Crushed silica was used as a raw material and spheroidized in a molten flame to obtain a D50 of 10 μm and a specific surface area of ​​3.5 m². 2 / g particles, and remove coarse particles larger than 25μm according to the method of Experimental Example 1, and use the metal oxide particle material prepared therefrom as the test sample of this Experimental Example.

[0086] (Experimental Example 7)

[0087] According to Test Example 1 of Japanese Patent Application Publication No. 2021-161008, 3-methacryloyloxypropyltrimethoxysilane was used to treat metal oxide particle materials (D50 of 150 nm, D100 of 270 nm, and specific surface area of ​​21.3 m²). 2 Hollow particles larger than 2μm (104 particles / 0.1g = 10 particles / 10mg) were surface-treated and used as the test sample in this experiment.

[0088] Test Example 1 of Japanese Patent Application Publication No. 2021-161008 is as follows. The raw material particle material used was silica, manufactured by the VMC method, with a volume average particle size of 300 nm and a specific surface area of ​​17.8 m². 2 / g particles.

[0089] The raw material particles were surface-treated using N-phenyl-3-aminopropyltrimethoxysilane as the silane compound. The amount of the silane compound was set at 2% based on the mass of the raw material particles.

[0090] The obtained particle material was dispersed in MEK to obtain a dispersion with a solid content of 20% by mass. For this dispersion, coarse particles were settled / removed by decantation in a centrifugal field under the conditions of centrifugal acceleration: 1700G and residence time: 2.8 minutes. (Centrifugal field residence time: minutes) / (Classification slurry viscosity: mPa) s) is 1.4, (centrifugal acceleration: G) / (grading slurry viscosity: mPa) The concentration (s) was 850. Then, the particles were removed by fractionation using filters with pore sizes of 5 μm, 3 μm, and 1 μm. The fractionated dispersions were dried in a dryer at 160°C for 30 minutes, and the dried metal oxide particle material was used as the test sample for this experiment.

[0091] (Experimental Example 8)

[0092] A 500 mL reaction vessel equipped with a stirrer was placed in a constant temperature bath. 43 g of ethanol, 46 g of water, and 51 g of 25% ammonia solution were added, and the mixture was heated to 50°C while stirring. Then, 105 g of tetraethoxysilane was added dropwise over 11 minutes while stirring the mixture. After addition, the solution was filtered to obtain silica particles. These particles were then dried at 130°C for 8 hours using a quasi-explosion-proof dryer, followed by calcination at 1000°C for 12 hours in a calcination furnace. The heating time during calcination was set to 2 hours, followed by a 12-hour holding period and natural cooling. The resulting metal oxide particles were spherical with a D50 of 0.7 μm. This metal oxide particle material was used as the test sample in this experimental example.

[0093] (Experimental Example 9)

[0094] The ethanol was changed to 75g, and the metal oxide particle material was prepared using the same method as in Example 8, except that it was used as the test sample for this example. The obtained metal oxide particle material was spherical with a D50 of 1.0 μm.

[0095] (Experimental Example 10)

[0096] The ethanol was replaced with 100g, and the metal oxide particle material was prepared using the same method as in Example 8, except that it was used as the test sample for this example. The obtained metal oxide particle material was spherical with a D50 of 2.0 μm.

[0097] (Experimental Example 11)

[0098] The raw material particles (silica, volume average particle size 2.0 μm) obtained by the VMC method were dispersed in isopropanol using a high-pressure disperser to obtain a dispersion (dispersion slurry) with a solid content concentration of 30% by mass.

[0099] By utilizing the difference in sedimentation velocity caused by different particle sizes in the dispersion, solid coarse particles larger than 3μm are removed by centrifugation.

[0100] Next, the slurry composition was classified once using filters with pore sizes of 7μm, 5μm, and 3μm to remove coarse particles larger than 3μm, including hollow particles, thus obtaining a classified slurry composition. The classified slurry was dried using a dryer, and the resulting silica particle material was used as the test sample in this embodiment.

[0101] (Experimental Example 12)

[0102] As a grading process, except that only the hollow particle removal process is performed and no surface treatment process is performed, the same as in Test Example 1, the metal oxide particle material is used as the test sample in this test example.

[0103] (Experimental Example 13)

[0104] 100g of raw metal oxide particles obtained in the manufacturing process of Example 1 were mixed with 10g of dried sample after the hollow particle separation process of Example 1, and used as the test sample for this example.

[0105] (Experimental Example 14)

[0106] Instead of the hollow particle separation process, a filter with a pore size of 5 μm was used to pass the particles through the filter three times. Otherwise, the process was the same as in Test Example 1, and the resulting metal oxide particle material was used as the test sample for this test example. It should be noted that in the sample that was only passed through the filter once, the hollow particle content was 4200 particles / 10 mg.

[0107] (Experimental Example 15)

[0108] Instead of the hollow particle separation process, a process of passing the particle through a filter with a pore size of 5 μm twice was adopted. Otherwise, the process was the same as in Test Example 1, and the resulting metal oxide particle material was used as the test sample for this test example. It should be noted that in the sample that was only passed through the filter once, the hollow particle content was 980 particles / 10 mg.

[0109] (evaluate)

[0110] Table 1 shows the following parameters for each test specimen in each test example: D50, specific surface area (SSA), lower limit of the particle size of removed coarse particles (top cutoff point), whether or not surface treatment was performed using methacryloxysilane, viscosity when filled with epoxy resin, content of coarse particles larger than 5 μm, content of hollow particles larger than 5 μm, and defect rate when manufacturing semiconductor packages.

[0111] D50 is a value determined by laser diffraction particle size distribution measurement. SSA is a value determined using nitrogen via the BET method. The viscosity when filled into epoxy resin is the viscosity at 25°C (shear rate 1s) when the test sample is uniformly dispersed in epoxy resin (manufactured by Nippon Steel Chemical & Material Co., Ltd., ZX-1059) at a concentration of 60% by mass of solids. -1 ).

[0112] The content of coarse and hollow particles was calculated by counting the particles based on image analysis of the test sample dispersed in the liquid. For the coarse particle count, an image processing device (SYSMEX Corporation: FPIA-3000) was used to count the number of coarse particles contained in a dispersion obtained by dispersing the test sample at a concentration of 3% by mass in MEK as the dispersion medium. The volume of the dispersion obtained from the count was taken as the volume containing 10g of the test sample.

[0113] The number of hollow particles was determined using the method described in paragraph 0046 of Japanese Patent Application Publication No. 2022-117398. Specifically, an image analysis particle size analyzer (IF-3200, manufactured by Jasco International) was used as the detection device for hollow particles. First, a test solution with a concentration of 30 mg / mL was prepared using a mixture of toluene and acetone adjusted to a mass ratio of 3:1 as the dispersion medium. Then, the obtained test solution was subjected to ultrasonic treatment for 2 minutes. Image detection was performed on each test solution using the above detection device, and the number of hollow particles in the test sample was counted (the number of hollow particles per 10 mg is expressed as the number of particles). In addition, the long axis of each hollow particle was measured, and the average value was calculated. It should be noted that the lens magnification of the detection device was 4x, and the thickness of the gasket in the measuring section was set to 300 μm. Images were captured using a CMOS camera mounted on the device, and sufficient images were captured to reach a quantity equivalent to 10 mg of silica. The obtained images were analyzed. In order to extract only hollow particles, only results with a roundness of 95% or higher were extracted for analysis. Here, cases with a coarse particle count of 500 ppm or more and a hollow particle count of 10,000 or more are denoted as "××".

[0114] The defect rate in semiconductor packaging is calculated by observing the number of hollow particles larger than 5 μm within a 1 cm × 1 cm area of ​​the sample under a microscope. The sample is obtained by grinding cured products obtained by mixing various test specimens with liquid resin and curing agent and then heating and curing. The cured product is prepared as follows: 16 g of the test specimen is mixed with 3.8 g of ZX-1059 and 1 g of curing agent ETHACURE300 (Mitsui Chemicals Fine Chemicals Co., Ltd.), and heated at 175°C for 2 hours to cure.

[0115] The number of hollow particles with a size greater than 5μm confirmed is less than 10 and classified as "Good"; more than 10 but less than 300 and classified as "Acceptable"; more than 300 and classified as "Poor". The viscosity of the liquid resin and curing agent during mixing is very high, reaching 170 Pa. Substances above s cannot be PKG converted.

[0116]

[0117] As shown in the table, test examples 1 and 14, 15 have low packaging defect rates and can perform excellently as fillers for sealing materials used in semiconductor packaging. These three test examples meet all the requirements (1)-(5) shown below, and it can be inferred that by meeting these requirements, they can perform high-performance as fillers for sealing materials used in semiconductor packaging.

[0118] Test examples 1-5 and 9-15 meet the following criteria: (1) D50 is 1.0 μm to 5.0 μm; (2) SSA is 1.0 μm. 2 / g~30m 2 / g of test examples 1-15; meets (3) the content of coarse particles with a particle size of 5μm or more is less than 300ppm of test examples 1-3, 7-15; meets (4) the content of hollow particles with a particle size of 5μm or more is less than 4000 particles / 10mg of test examples 1, 7-15; meets (5) the viscosity of the resin composition when filled into the resin material with a solid component concentration of 60% by mass is 170Pa. less than s (shear rate is 1s) -1 Test examples 1, 2, 4-6, 14, and 15.

Claims

1. A metal oxide particle material, with metal oxide as the main component, The D50, determined by laser diffraction particle size distribution, ranges from 1.0 μm to 5.0 μm. Specific surface area is 1.0 m² 2 / g~30m 2 / g, The content of coarse particles with a particle size of 5 μm or larger is below 300 ppm. The content of hollow particles with a particle size of 5μm or larger is less than 4000 per 10mg. The viscosity of the resin composition when filled with a solid content of 60% by mass into the resin material is 170 Pa. Below s, among which, The viscosity is such that the shear rate is 1s. -1 Viscosity at that time.

2. The metal oxide particle material according to claim 1, wherein, Surface treatment was performed using silane compounds.

3. The metal oxide particle material according to claim 1 or 2, wherein, The content of hollow particles with a particle size of 2μm or larger is less than 4000 per 10mg.

4. The metal oxide particle material according to any one of claims 1 to 3, wherein, Flaxseed oil has an oil absorption rate of less than 2.7g / 15g.

5. A resin composition comprising a resin composition having a metal oxide particle material as described in any one of claims 1 to 4 and a resin material dispersing the metal oxide particle material.

6. A slurry composition comprising a metal oxide particle material according to any one of claims 1 to 4 and a dispersion medium for dispersing said metal oxide particle material.

7. A method for manufacturing a metal oxide particle material, comprising the method for manufacturing the metal oxide particle material according to any one of claims 1 to 4, and comprising: The manufacturing process involves subjecting raw material particles, primarily composed of metals constituting the metal oxide particle material, to a high-temperature oxidizing atmosphere for deflagration, followed by cooling, thereby producing raw material metal oxide particle materials with a D50 of 1.0 μm to 5.0 μm; and The grading process categorizes the raw material metal oxide particles to a content of less than 300 ppm for coarse particles with a particle size of 5 μm or larger, and less than 4000 hollow particles with a particle size of 5 μm or larger per 10 mg.

8. The method for manufacturing metal oxide particle material according to claim 7, wherein, The grading process includes a hollow particle separation process, in which the raw material metal oxide particles are dispersed in a liquid dispersion medium to separate the hollow particles with a smaller specific gravity.

9. The method for manufacturing metal oxide particle material according to claim 7 or 8, wherein, The temperature of the high-temperature oxidizing atmosphere is above 2000℃.

10. A filler for a sealing material used in semiconductor packaging, comprising any one of the metal oxide particle materials according to claims 1 to 4.

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