Paste for internal electrodes of multilayer ceramic electronic components, and method for manufacturing multilayer ceramic electronic components.

Abstract

This invention provides a paste for internal electrodes of multilayer ceramic electronic components and a method for manufacturing multilayer ceramic electronic components, which raises the temperature at which the silver film begins to shrink and expand during the heat treatment process in the manufacturing process of multilayer electronic components. [Solution] The internal electrode paste used for forming internal electrodes of the multilayer ceramic electronic component disclosed herein comprises silver powder, a resin binder, an organic solvent, and titanium dioxide powder. The silver powder has a volume-based particle size distribution based on laser diffraction scattering, with the smallest particle size corresponding to 50% of the cumulative value. 50 The diameter is at least 1 μm. Titanium dioxide powder is composed of spherical titanium dioxide particles.

Description

[Technical Field]

[0001] This disclosure relates to a paste for internal electrodes of multilayer ceramic electronic components, and to a method for manufacturing multilayer ceramic electronic components. [Background technology]

[0002] The paste for internal electrodes disclosed in Japanese Patent Publication No. 2987995 consists of 0.2 to 3.0% by weight of titanium oxide particles, with the remainder being conductive noble metal particles, an organic binder, and an organic solvent. The titanium oxide particles are needle-shaped or plate-shaped. The publication states that this configuration can suppress cracking in the dielectric layer and delamination between the dielectric layer and the internal electrodes.

[0003] The conductive paste disclosed in Japanese Patent Publication No. 3589239 contains a conductive component and an organic vehicle component, and is used to co-fire with a ceramic molded body obtained by laminating multiple green sheets. The conductive component contains conductive powder coated with a metal oxide. This conductive paste is used in the via-hole connection portion formed in the green sheet. The publication states that when a ceramic molded body is made using a conductive paste of this configuration in the via-hole connection portion and then fired to obtain a ceramic multilayer substrate, warping and deformation can be made less likely to occur in this ceramic multilayer substrate.

[0004] Japanese Patent Publication No. 7489824 discloses a conductive paste for thin films used in forming thin film electrode layers with a thickness of 1 μm to 3 μm. This conductive paste comprises conductive powder, manganese oxide powder, a binder, and a solvent. The manganese oxide powder has a cumulative 50% particle size (D) measured by particle size distribution measurement based on SEM observation. 50 ) is 500 nm or less, and the cumulative 90% particle size (D 90 ) and cumulative 10% particle size (D 10 ) difference (D 90 -D 10The wavelength is 700 nm or less. The publication states that an electrode layer with excellent surface smoothness can be formed with this configuration. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Patent No. 2987995 [Patent Document 2] Patent No. 3589239 [Patent Document 3] Patent No. 7489824 [Overview of the project] [Problems that the invention aims to solve]

[0006] To form the internal electrodes of electronic components, for example, silver powder may be used. The process for manufacturing electronic components may include a step of heat-treating the silver powder to sinter it. To form the internal electrode layer, for example, an internal electrode paste containing silver powder may be used. In this case, the process for manufacturing electronic components may include a step of applying the internal electrode paste to a substrate and heat-treating the coating of the internal electrode paste. The internal electrode paste contains organic components such as a resin binder and an organic solvent for various purposes. Such organic components burn out, for example, during the heat-treating process. At this time, for example, gases derived from the organic components are generated. Meanwhile, the heat-treating process causes the silver powder to sinter and a silver film to be formed. During the heat-treating process, the organic components burn out at a relatively low temperature range, and the sintering of the silver powder begins at a relatively high temperature range. As the sintering of the silver powder progresses, the silver film tends to shrink.

[0007] However, some organic components may remain in the temperature range where silver powder sintering begins. These remaining organic components burn off in the temperature range where silver powder sintering begins, or at a higher temperature range. When at least a portion of the silver powder is sintered, gases derived from the remaining organic components become less likely to escape from between the silver powder particles. As a result, as the sintering of the silver powder progresses, the silver film may shift from a tendency to shrink to a tendency to expand. Such a change in the behavior of the silver film is undesirable because it can cause cracks to form in the internal electrodes, for example.

[0008] In recent years, multilayer ceramic electronic components have become more diverse. Consequently, a wider range of substrate materials are being considered for use as the base material for internal electrodes. Depending on the substrate material, for example, higher temperature heat treatments may be required.

[0009] In light of these circumstances, the inventors of the present invention wanted to raise the temperature at which the silver film begins to shrink, as well as the temperature at which the silver film changes from shrinking to expanding, in the heat treatment process used in the manufacturing of multilayer electronic components. [Means for solving the problem]

[0010] The technology disclosed herein provides an internal electrode paste used for forming internal electrodes of multilayer ceramic electronic components. The internal electrode paste comprises silver powder, a resin binder, an organic solvent, and titanium dioxide powder. The silver powder has a volume-based particle size distribution based on laser diffraction scattering, with the smallest particle size corresponding to 50% of the integrated value. 50 The diameter is at least 1 μm. The titanium dioxide powder is composed of spherical titanium dioxide particles. This configuration makes it possible to raise the shrinkage initiation temperature of the silver film and suppress the expansion behavior of the silver film during the heat treatment process in the manufacturing of multilayer electronic components.

[0011] The technology disclosed herein provides a method for manufacturing multilayer ceramic electronic components. This manufacturing method includes applying the internal electrode paste to a substrate and firing the coating of the internal electrode paste and the substrate. With this configuration, it is possible to raise the shrinkage initiation temperature of the silver film and suppress the expansion behavior of the silver film during the heat treatment step in the manufacturing process of the multilayer electronic component. [Brief explanation of the drawing]

[0012] [Figure 1] Figure 1 is a schematic cross-sectional view of a multilayer chip inductor 1. [Figure 2] Figure 2 shows the graph obtained from the thermal analysis of Example 11. [Figure 3] Figure 3 shows the graph obtained from the thermal analysis of Example 17. [Figure 4] Figure 4 shows the graph obtained from the thermal analysis of Example 21. [Figure 5] Figure 5 shows the graph obtained from the thermal analysis of Example 22. [Figure 6] Figure 6 shows the graph obtained from the thermal analysis of Example 23. [Figure 7] Figure 7 shows the graph obtained from the thermal analysis of Example 24. [Modes for carrying out the invention]

[0013] Preferred embodiments of the technology disclosed herein are described below. Matters other than those specifically mentioned herein that are necessary for carrying out the technology disclosed herein can be understood based on the technical content taught herein and the common technical knowledge of those skilled in the art. The technology disclosed herein can be carried out based on the content disclosed herein and the common technical knowledge of the art. The A-B (A and B are arbitrary numbers) designations in this specification and the claims mean A or greater and B or less, and also include the case where A is greater than and B is less than or equal to.

[0014] According to the technology disclosed herein, an internal electrode paste used for forming an internal electrode of a multilayer ceramic electronic component is disclosed. This internal electrode paste contains silver powder, a resin binder, an organic solvent, and titanium dioxide powder. The silver powder has a D 50 iameter (hereinafter, simply referred to as "D 50 iameter").) of at least 1 μm of silver powder. The titanium dioxide powder is composed of spherical titanium dioxide particles.

[0015] The inventor considered that it is desirable to improve the dispersibility of the internal electrode paste in order to make the distribution of the silver powder in the internal electrode more uniform. It has been found that a preferable dispersion effect can be obtained by using silver powder having a D 50 iameter of at least 1 μm. However, it has been found that cracks are likely to occur in the internal electrode when using silver powder of such D 50 iameter. The inventor considered that the occurrence of cracks can be suppressed by raising the shrinkage start temperature of the silver film obtained by using an internal electrode paste containing silver powder having a D 50 iameter of at least 1 μm, and examined its composition.

[0016] Silver powder is a component that imparts electrical conductivity to the fired film (hereinafter also referred to as "internal electrode" or "silver film") obtained by firing the paste for the internal electrode. Silver powder is composed of, for example, silver particles. Examples of silver particles include particles made of elemental silver (Ag), particles made of silver-containing alloys (e.g., Ag / Pd alloy, Ag / Pt alloy, Ag / Cu alloy, etc.) (e.g., alloys containing 70% or more by mass of silver (preferably 80% or more by mass, more preferably 90% or more by mass, and even more preferably 95% or more by mass)), silver-coated particles having a silver-containing coating layer on the surface of the core particles, and core-shell particles in which the core particles are made of silver and the shell covering the core particles is made of a metal other than silver (e.g., palladium, platinum, copper, etc.), a silver-containing alloy, etc. Silver powder may contain, for example, unavoidable impurities generated during the manufacturing process of silver particles. The purity of the silver powder is generally 98% or higher, for example 99% or higher, preferably 99.5% or higher, more preferably 99.8% or higher, even more preferably 99.9% or higher, and the closer to 100%, the better.

[0017] Silver powder D 50 The diameter can be, for example, 1 μm or more, and can be set appropriately depending on the desired function of the internal electrode. From the viewpoint of improving the dispersibility of silver powder in the paste for the internal electrode, the D of the silver powder 50 The diameter is preferably 2 μm or larger, more preferably 3 μm or larger, and even more preferably 4 μm or larger. On the other hand, the smaller the size of the silver particles, the higher the sinterability between the silver particles, and the lower the resistance of the internal electrodes can be achieved. From this viewpoint, the D of the silver powder 50 The diameter is, for example, 20 μm or less, preferably 15 μm or less, more preferably 10 μm or less, and even more preferably 8 μm or less.

[0018] In the volume-based particle size distribution of silver powder based on laser diffraction scattering, D corresponds to 10% of the cumulative value from the smallest particle size. 10 Diameter (hereinafter simply referred to as "D") 10 Also called "diameter". The diameter can be set to approximately 0.1 μm to 10 μm. From the viewpoint of preventing short-circuit failure due to penetration of fine particles (silver particles) into the substrate, the D of the silver powder 10The diameter is, for example, 0.3 μm or more, preferably 0.5 μm or more, more preferably 1 μm or more, and even more preferably 1.5 μm or more. On the other hand, from the viewpoint of improving the sinterability of the internal electrode, the silver powder D 10 The diameter is, for example, 7.5 μm or less, preferably 5 μm or less, and more preferably 3 μm or less.

[0019] In the volume-based particle size distribution of silver powder based on laser diffraction scattering, D corresponds to 90% of the cumulative value from the smallest particle size. 90 Diameter (hereinafter simply referred to as "D") 90 Also called "diameter". The diameter can be set to approximately 3 μm to 30 μm. From the viewpoint of improving the heat resistance of silver powder in the paste for internal electrodes, the D of the silver powder 90 The diameter is, for example, 5 μm or more, preferably 7 μm or more, more preferably 9 μm or more, and even more preferably 10 μm or more. From the viewpoint of making the particle size distribution sharper and improving the continuity and smoothness of the internal electrode, the silver powder D 90 The diameter is, for example, 50 μm or less, preferably 40 μm or less, more preferably 35 μm or less, and even more preferably 30 μm or less.

[0020] The shape of the silver particles constituting the silver powder is not particularly limited, as long as the effects of the technology disclosed herein are realized.

[0021] When the entire internal electrode paste is considered as 100% by mass, the silver powder content is generally 60% by mass or more, or 70% by mass or more, for example, 80% by mass or more, preferably 85% by mass or more, and more preferably 90% by mass or more. This can improve, for example, the density of the internal electrode. When the entire internal electrode paste is considered as 100% by mass, the silver powder content is generally 99% by mass or less, for example, 98% by mass or less, preferably 97% by mass or less, and more preferably 96% by mass or less. This allows for the addition of appropriate amounts of components other than silver powder to the internal electrode paste.

[0022] The resin binder is, for example, a component that binds the silver powder, titanium dioxide powder, and substrate together when the internal electrode paste is applied (coated) onto the substrate. Preferably, the resin binder is a component that burns through during the firing of the internal electrode paste. The type of resin binder is not particularly limited, and conventional resin binders used in this type of internal electrode paste can be used, depending on the method of applying the internal electrode paste to the substrate, for example.

[0023] Examples of resin binders include celluloses such as methylcellulose, ethylcellulose, hydroxymethylcellulose, hydroxyethylcellulose, and carboxymethylcellulose; acrylic resins such as polymethyl methacrylate, polyethyl methacrylate, and polybutyl methacrylate; epoxy resins; phenolic resins; alkyd resins; polyvinyl alcohol; polyvinyl butyral; rosins such as rosin and maleated rosin; and the like. One of the above-mentioned resin binders may be used alone, or two or more may be used in combination. When the total internal electrode paste is considered to be 100% by mass, the content of the resin binder is generally 0.1% to 3% by mass, and preferably 0.3% to 1% by mass.

[0024] The organic solvent is a component that dissolves or disperses, for example, silver powder, resin binder, titanium dioxide powder, and other components. The type of organic solvent is not particularly limited and can be selected from those that are conventionally known. The organic solvent can be used, for example, by using one type of organic solvent alone or by using two or more types in appropriate combinations. Examples include alcohol-based solvents having an -OH group, ether-based solvents having an ether bond (RO-R'), ester-based solvents having an ester bond (RC(=O)-O-R'), and hydrocarbon-based solvents composed of carbon atoms and hydrogen atoms.

[0025] Examples of alcohol-based and ether-based solvents include terpineol, texanol, dihydroterpineol, benzyl alcohol, 3-methoxy-3-methyl-1-butanol, diethylene glycol, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, propylene glycol monobutyl ether, dipropylene glycol dimethyl ether, dipropylene glycol n-butyl ether, dipropylene glycol methyl n-propyl ether, dipropylene glycol methyl ether acetate, and dipropylene glycol methyl n-butyl ether.

[0026] Examples of ester solvents include 3-methoxy-3-methyl-1-butanol acetate, 3-methoxybutyl acetate, 1,3-butylene glycol diacetate, 1,4-butanediol diacetate, 1,6-hexanediol diacetate, propylene glycol monomethyl ether acetate, isobornyl acetate, carbitol acetate, ethyl diglycol acetate, butyl cellosolve acetate, propylene glycol diacetate, diethylene glycol monobutyl ether acetate, terpineol acetate, and dihydroterpineol acetate. Examples of hydrocarbon solvents include aliphatic hydrocarbon solvents such as petroleum hydrocarbons, naphtha, dipentene, turpentine oil, and mineral spirits; aromatic hydrocarbon solvents such as benzene, toluene, and xylene; paraffinic solvents such as normal paraffins and isoparaffins; and naphthenic solvents such as monocyclic naphthenes and bicyclic naphthenes. When the entire paste for the internal electrodes is considered as 100% by mass, the content of the organic solvent is generally 0.5% to 10% by mass, and preferably 2% to 7% by mass.

[0027] Titanium dioxide powder is a component that, for example, has the function of promoting the combustion of organic components. Therefore, by including titanium dioxide powder in the internal electrode paste, it is possible to promote the emission of gases derived from organic components before the sintering of silver powder progresses. In addition, titanium dioxide powder may have the function of delaying the sintering of silver powder. Therefore, by including titanium dioxide powder in the internal electrode paste, the sintering of silver powder can be delayed when the internal electrode paste is subjected to heat treatment. The functions of titanium dioxide powder will be described further later.

[0028] As described above, the titanium dioxide particles constituting the titanium dioxide powder in the internal electrode paste disclosed herein are spherical. In this specification, with respect to titanium dioxide particles and other oxide particles described later, "spherical" means that the average aspect ratio of the titanium dioxide particles or other oxide particles is approximately 1 to 1.5, for example 1 to 1.3, preferably 1 to 1.2, more preferably 1 to 1.15, and even more preferably 1 to 1.1. The average aspect ratio of titanium dioxide particles or other oxide particles can be obtained, for example, by observing titanium dioxide powder or other oxide powder (titanium dioxide particles or other oxide particles) with an SEM, randomly selecting a number of particles (e.g., 10 to 300) from the obtained observation images, calculating the aspect ratio (ratio of major axis to minor axis) based on the major axis and minor axis of each particle, and obtaining the arithmetic mean.

[0029] The specific surface area of ​​titanium dioxide powder is not particularly limited, as long as the effects of the technology disclosed herein are realized. The specific surface area of ​​titanium dioxide powder is approximately 10 m². 2 / g~150m 2 It is preferable that the specific surface area is 15 m² / g. The larger the specific surface area, the greater the effect of delaying the sintering of silver powder, for example, by allowing it to penetrate between silver particles in the paste for internal electrodes. In addition, the effect of promoting combustion as described above can be enhanced. From this viewpoint, the specific surface area of ​​titanium dioxide powder should be, for example, 15 m² / g. 2 / g or more, 20m 2Preferably 25m / g or more. 2 More preferably 30m 2 A value of 150 m² or more is even more preferable. On the other hand, the smaller the specific surface area, the greater the effect of slowing down the sintering of silver powder, for example, by widening the gaps between silver particles in the paste for internal electrodes. In addition, it becomes easier to release gases derived from organic components. From this viewpoint, the specific surface area of ​​titanium dioxide powder is, for example, 150 m². 2 It is less than / g and 140m 2 Preferably less than / g, 130m 2 Less than / g is more preferable, 120m 2 A value of less than / g is even more preferable. The specific surface area of ​​titanium dioxide powder and the specific surface area of ​​other oxide powders described later can be calculated based on the BET method, for example, in accordance with the "Method for measuring the specific surface area of ​​powders (solids) by gas adsorption" specified in JIS Z 8830:2013 (ISO9277:2010). Alternatively, the manufacturer's nominal value may be used.

[0030] For example, the following equation (P): DB1 = 6 / (S × ρ) (P) By using this method, the average particle size DB1 (nm) of the titanium dioxide powder can be obtained. Here, in formula (P) above, S is the specific surface area of ​​the titanium dioxide powder and ρ is the density of the titanium dioxide powder. The average particle size DB1 of the titanium dioxide powder is not particularly limited as long as the effects of the technology disclosed herein are realized, but is generally 5 nm to 140 nm, preferably 10 nm to 50 nm.

[0031] The paste for the internal electrodes is, for example, 1.0 × 10¹⁶ parts per 100 parts by mass of silver powder. -3 Part of mass ~5.0×10 -2 It contains parts by mass of titanium dioxide powder. The higher the ratio of titanium dioxide powder to 100 parts by mass of silver powder, the higher the shrinkage start temperature of the silver film tends to be. From this viewpoint, the paste for the internal electrode preferably contains 1.5 × 10 parts by mass of titanium dioxide powder per 100 parts by mass of silver powder. -3 parts by mass or more, more preferably 2.0 × 10 -3parts by mass or more, more preferably 2.5 × 10 -3 It contains more than 4.5 parts by mass. The smaller the ratio of titanium dioxide powder to 100 parts by mass of silver powder, the more effectively the increase in resistance of the internal electrode can be suppressed. From this viewpoint, the paste for the internal electrode preferably contains 4.5 × 10 parts by mass of silver powder. -2 parts by mass or less, more preferably 4.0 × 10 -2 parts by mass or less, more preferably 3.5 × 10 -2 It contains parts by mass or less.

[0032] When the entire paste for the internal electrodes is considered as 100% by mass, the titanium dioxide powder content is preferably about 5 ppm to 450 ppm. From the viewpoint of raising the shrinkage initiation temperature of the silver film and raising the temperature at which the silver film changes from shrinking to expanding, when the entire paste for the internal electrodes is considered as 100% by mass, the titanium dioxide powder content is preferably 10 ppm or more, more preferably 15 ppm or more, and more preferably 20 ppm or more. From the viewpoint of suppressing the increase in resistance of the internal electrodes, when the entire paste for the internal electrodes is considered as 100% by mass, the titanium dioxide powder content is preferably 400 ppm or less, and more preferably 350 ppm or less.

[0033] The paste for internal electrodes disclosed herein is, as described above, D 50 The paste contains silver powder with a diameter of at least 1 μm. This improves the dispersibility of the silver powder in the internal electrode paste, enabling the realization of an internal electrode with a more uniform silver distribution. The internal electrode paste contains titanium dioxide powder composed of spherical titanium dioxide particles. This allows for a higher shrinkage start temperature of the silver film formed when heat is applied to the coating film of the internal electrode paste during the heat treatment step in the manufacturing process of internal electrodes for multilayer ceramic electronic components, and also raises the temperature at which the silver film shifts from shrinking to expanding.

[0034] The inventors believe the mechanism by which the above-mentioned effects are obtained is as follows. However, there is no intention to limit the mechanism by which such effects are obtained to those described below.

[0035] Conventionally, when a silver paste containing silver powder, a resin binder, and an organic solvent is heat-treated, the organic components in the silver paste generally burn out within a temperature range of up to approximately 300°C. However, some organic components require heat treatment at higher temperatures to burn out, and these components remain until reaching that temperature range. The remaining organic components begin to burn from the surface side at a temperature range of approximately 600°C, and burn out as the temperature rises. On the other hand, the sintering of silver powder generally begins at around 400°C. The sintering of silver powder progresses with increasing temperature, forming a silver film. As the sintering of silver powder progresses, the silver film shrinks, but for example, the release of gases derived from the remaining organic components is hindered. Therefore, the silver film may begin to expand.

[0036] Titanium dioxide powder contained in the internal electrode paste has a catalytic effect that, for example, promotes the combustion of organic components. Therefore, the titanium dioxide powder can promote the combustion of remaining organic components before the sintering of the silver powder progresses. In other words, if the internal electrode paste contains titanium dioxide powder, when the paste coating is heat-treated, the heat applied can be used to burn remaining organic components before it is used to sinter the silver powder. This can suppress the residue of organic matter in the silver film. Furthermore, the titanium dioxide powder can penetrate between the silver particles that make up the silver powder, slowing down the sintering of the silver powder. Because the titanium dioxide powder is spherical, the silver powder and titanium dioxide powder can be dispersed more uniformly in the coating of the internal electrode paste, and the packing ability of both powders can be improved. This can enhance the effect of slowing down the sintering of the silver powder and make it easier to discharge gases generated during the heat treatment process. This suppresses the conversion of the silver film's contraction into expansion, or allows the temperature at which the silver film's contraction converts into expansion to be raised, enabling the heat treatment to be performed at a higher temperature.

[0037] While not particularly limited, the internal electrode paste disclosed herein may further contain, if necessary, other oxide powders different from titanium dioxide powder (hereinafter simply referred to as "other oxide powders"). Other oxide powders can, for example, penetrate between the silver particles constituting the silver powder, thereby slowing down the sintering of the silver powder. By including both titanium dioxide powder and other oxide powders in the internal electrode paste, the effect of slowing down the sintering of the silver powder can be enhanced compared to when titanium dioxide powder is included alone. For this reason, for example, gas generated by the catalytic action of titanium dioxide powder can be better discharged, and the effect of suppressing the conversion of the silver film's contraction to expansion, or the effect of raising the temperature at which the silver film's contraction converts to expansion, can be further enhanced. This makes it possible to perform the above heat treatment at an even higher temperature than when titanium dioxide powder is included alone.

[0038] Other oxide powders are not particularly limited as long as the effects of the technology disclosed herein are realized, and any oxide powder used in this type of application may be used. The other oxide powders preferably contain at least one of the following: alumina, silica, zirconia, ceria, yttria, zeolite, copper oxide, iron oxide, zinc oxide, etc. In particular, from the viewpoint of further enhancing the effect of suppressing the conversion of the silver film's shrinkage into expansion, or the effect of raising the temperature at which the silver film's shrinkage converts into expansion, the other oxide powders preferably contain silica and / or alumina.

[0039] The shape of the other oxide particles constituting the other oxide powder is not particularly limited, as long as the effects of the techniques disclosed herein are realized. The shape of the other oxide particles may be spherical or non-spherical, but spherical is preferred.

[0040] The specific surface area of ​​other oxide powders is not particularly limited, as long as the effects of the techniques disclosed herein are realized. The specific surface area of ​​other oxide powders is approximately 50 m². 2 / g~150m2 It is preferable that the specific surface area of ​​the other oxide powder is 55 m² / g. The larger the specific surface area of ​​the other oxide powder, the greater the effect of delaying the sintering of the silver powder, for example, by getting between the silver particles in the paste for the internal electrodes. From this viewpoint, the specific surface area of ​​the other oxide powder should be, for example, 55 m² / g. 2 / g or more, 60m 2 Preferably 65m / g or more. 2 More preferably 70m 2 A value of 140 m² or more is even more preferable. On the other hand, the smaller the specific surface area of ​​the other oxide powder, the greater the effect of slowing down the sintering of the silver powder, for example, by widening the gaps between silver particles in the paste for the internal electrodes. This makes it easier to release gases derived from organic components. From this viewpoint, the specific surface area of ​​the other oxide powder is, for example, 140 m². 2 It is less than / g and 130m 2 Preferably less than / g, 120m 2 Less than / g is preferable.

[0041] For example, the following equation (Q): DB2 = 6 / (S × ρ) (Q) By using this method, the average particle size DB2 (nm) of the other oxide powder can be obtained. Here, in formula (Q) above, S is the specific surface area of ​​the other oxide powder and ρ is the density of the other oxide powder. The average particle size DB2 of the other oxide powder is not particularly limited as long as the effects of the disclosed technology are realized, but is generally 5 nm to 50 nm, preferably 10 nm to 40 nm.

[0042] From the viewpoint of realizing the effects of the technology disclosed herein, the mass ratio of titanium dioxide powder to other oxide powders (titanium dioxide powder:other oxide powder) is preferably 1:9 to 9:1, and more preferably 1:4 to 4:1. Although not particularly limited, increasing the relative mass ratio of the other oxide powders to the titanium dioxide powder can enhance the effect of slowing down the sintering of the silver powder. For example, this makes it possible to more effectively remove gases generated by the catalytic action of titanium dioxide powder, thereby raising the shrinkage start temperature of the silver film and making it easier to suppress the expansion of the silver film.

[0043] When the paste for the internal electrode contains both titanium dioxide powder and other oxide powders, the combined content ratio of titanium dioxide powder and other oxide powders in the internal electrode paste relative to 100 parts by mass of silver powder is, for example, 1.0 × 10⁻⁶. -3 Part of mass ~5.0×10 -2 It is preferable that the amount be in parts by mass. The higher the combined content of titanium dioxide powder and other oxide powders relative to 100 parts by mass of silver powder, the higher the shrinkage initiation temperature of the silver film tends to be. From this viewpoint, the paste for the internal electrode preferably contains 1.5 × 10 parts by mass of titanium dioxide powder and other oxide powders relative to 100 parts by mass of silver powder. -3 parts by mass or more, more preferably 2.0 × 10 -3 parts by mass or more, more preferably 2.5 × 10 -3 It contains more than 10 parts by mass. The smaller the combined content ratio of titanium dioxide powder and other oxide powders per 100 parts by mass of silver powder, the more effectively the increase in resistance of the internal electrode can be suppressed. From this viewpoint, the paste for the internal electrode contains, preferably, 4.5 × 10 parts by mass of titanium dioxide powder and other oxide powders per 100 parts by mass of silver powder. -2 parts by mass or less, more preferably 4.0 × 10 -2 parts by mass or less, more preferably 3.5 × 10 -2 It contains parts by mass or less.

[0044] While not particularly limited, in one preferred embodiment, from the viewpoint of realizing the effects of the technology disclosed herein, the paste for the internal electrode is 1.0 × 10 -3 Part of mass ~1.0×10 -2 The mass of titanium dioxide powder and 1.0 × 10 -3 Part of mass ~1.0×10 -2 It contains part by mass of oxide powder. In a more preferred embodiment, from the viewpoint of realizing the effects of the technology disclosed herein, the paste for the internal electrode is 2.0 × 10 -3 Part of mass ~8.0×10 -3 The mass of titanium dioxide powder and 2.0 × 10 -3 Part of mass ~8.0×10 -3 It contains parts by mass of oxide powder.

[0045] The paste for internal electrodes may contain various additives in addition to the components described above. Conventional known additives used in this type of application may be used. Examples of additives include inorganic fillers (excluding the titanium dioxide powder and other oxide powders mentioned above), dispersants, surfactants, viscosity modifiers, defoamers, plasticizers, antioxidants, and pigments. When the entire paste for internal electrodes is considered as 100% by mass, the content of additives is generally 5% by mass or less, for example, 3% by mass or less, preferably 2% by mass or less, and more preferably 1% by mass or less.

[0046] The technology disclosed herein provides a method for manufacturing multilayer ceramic electronic components. This manufacturing method includes applying the internal electrode paste to a substrate and firing the coating of the internal electrode paste and the substrate. In this embodiment, the manufacturing method includes a preparation step, a coating step, and a firing step.

[0047] The preparation step involves, for example, preparing silver powder, titanium dioxide powder, and other oxide powders as needed. In this embodiment, the preparation step involves preparing an internal electrode paste. The internal electrode paste is prepared, for example, by mixing the above-mentioned components. A conventionally known mixer used in this type of application can be used as the mixer without any particular limitations.

[0048] The coating step is, for example, the step of applying an internal electrode paste onto a substrate. Any conventionally known method used in this type of application may be used as the means for applying the internal electrode paste, but preferred methods include various printing methods such as screen printing, gravure printing, offset printing, and inkjet printing; the doctor blade method; the spray method; and so on.

[0049] The firing process is a process in which, for example, after the coating process, the substrate and the coating film of the internal electrode paste applied to the substrate are subjected to heat treatment (firing). In this embodiment, in the firing process, after the coating process, the substrate and the coating film of the internal electrode paste applied to the substrate are subjected to heat treatment. The conditions for the heat treatment (firing) are not particularly limited and can be set appropriately depending on the application of the electronic component, the material of the substrate, etc. The temperature of the heat treatment should be set to a temperature at which, for example, the organic components in the internal electrode paste burn out and the silver powder sintersects. The temperature of the heat treatment can be set to, for example, 500°C to 1000°C (for example, 600°C to 900°C, or 600°C to 800°C). The time of the heat treatment should be set to, for example, 30 minutes to 10 hours. The atmosphere during the heat treatment should be, for example, an air atmosphere, or an inert atmosphere such as a nitrogen atmosphere or a noble gas atmosphere.

[0050] The manufacturing method for multilayer ceramic electronic components disclosed herein is not limited to the embodiments described above. For example, this manufacturing method may include any additional steps besides those described above. This manufacturing method may include, for example, a drying step, a pressing step, etc., as needed. The drying step is, for example, a step to volatilize the organic solvent in the paste for the internal electrodes, and is preferably carried out between the coating step and the firing step. The drying conditions are not particularly limited and can be appropriately set depending on the type and amount of organic solvent used. The pressing step is, for example, a step to press the silver powder applied to the substrate, and is preferably carried out between the coating step and the firing step. The pressing conditions are not particularly limited and can be appropriately set depending on the application of the multilayer ceramic electronic component, the desired thickness of the internal electrodes (layers), etc.

[0051] The following describes a multilayer chip inductor, an example of an electronic component. Figure 1 is a schematic cross-sectional view of multilayer chip inductor 1. Note that the dimensional relationships (length, width, thickness, etc.) in Figure 1 do not necessarily reflect the actual dimensional relationships. The symbols X and Z in the drawing represent the left-right and up-down directions, respectively. However, this is merely a directional distinction for the sake of explanation.

[0052] The size of the multilayer chip inductor 1 shown in Figure 1 is not particularly limited, but it is preferable to have sizes such as 1608 shape (1.6 mm × 0.8 mm) or 2520 shape (2.5 mm × 2.0 mm). The multilayer chip inductor 1 comprises a main body 10 and external electrodes 20.

[0053] The multilayer chip inductor 1 comprises a main body 10 and external electrodes 20 provided on both sides of the main body 10 in the left-right direction X. In the main body 10, for example, a plurality of magnetic material layers 12 are stacked in the vertical direction Z and integrated with each other. Examples of materials constituting the magnetic material layers 12 include ferrite magnetic materials such as Ni-Cu-Zn ferrite; Fe-Cr-Si alloy; Fe-Al-Si alloy; Fe-Si-M soft magnetic alloy (where M is at least one of chromium, aluminum, and titanium); and other metallic materials.

[0054] Between each magnetic layer 12, a coil conductor is provided as an internal electrode layer 14. In this embodiment, the coil conductor is a fired film of the internal electrode paste disclosed herein. Two coil conductors adjacent to each other in the vertical Z direction, with the magnetic layer 12 in between, are electrically connected through via holes provided in the magnetic layer 12. As a result, the internal electrode layer 14 is configured in a three-dimensional coil shape (helical). Both ends of the coil conductor are connected to the external electrodes 20.

[0055] A multilayer chip inductor 1 can be manufactured, for example, by the following procedure. First, a magnetic paste containing a metal material constituting the magnetic layer 12, a binder, and an organic solvent is prepared and supplied onto a carrier sheet to form a green sheet. Next, the green sheet is rolled and dried. Then, the green sheet is cut to a desired size to obtain a plurality of magnetic layer forming sheets. Next, via holes are formed at predetermined positions on these magnetic layer forming sheets using a drill or the like. Next, the internal electrode paste disclosed herein is printed in a predetermined coil pattern at predetermined positions on the plurality of magnetic layer forming sheets and dried. Then, these are laminated and pressed together to produce a laminate of unfired green sheets. By firing this, the green sheets are fired integrally, and a body 10 comprising the magnetic layer 12 and the internal electrode layer 14 is formed. Finally, an external electrode forming paste is applied to both ends of the body 10 and fired to form external electrodes 20. In this way, a multilayer chip inductor 1 can be manufactured.

[0056] The following describes test examples related to the technology disclosed herein, but it is not intended to limit the technology disclosed herein to these test examples.

[0057] <Test 1> -Example 11- Silver powder A was prepared. When the particle size distribution of silver powder A was analyzed, D 10 The diameter is 2.0 μm, D 50 The diameter is 5.3 μm, D 90The diameter was 12 μm. Microtrac's "MT3300EX" was used to analyze the particle size distribution of the silver powder. Ethyl cellulose was prepared as the resin binder. Diethylene glycol monobutyl ether acetate was prepared as the organic solvent. Titanium dioxide powder A was prepared as an additive. Titanium dioxide powder A was spherical and had a specific surface area of ​​70 m². 2 / g~110m 2 The density is 4.3 g / cm³ / g. 3 The particle size was 16 nm to 20 nm. The particle size was calculated using the above formula (P).

[0058] A silver paste was prepared by mixing the prepared silver powder A, resin binder, organic solvent, and titanium dioxide powder A using a mixing device. When the total silver paste is considered to be 100% by mass, the content of silver powder A was 95% by mass, the content of the resin binder was 0.68% by mass, the content of titanium dioxide powder A was 0.01% by mass (100 ppm), and the remaining organic solvent content was 4.31% by mass. In the silver paste, 1.1 × 10¹⁶ parts per 100 parts by mass of silver powder A were used. -2 The mixture contained titanium dioxide powder A by mass. Next, the silver paste was dried, and the dried paste was pulverized to obtain paste powder. Then, using a uniaxial molding machine (a hydraulic press PHK5-S manufactured by Towa Seiki Co., Ltd.), the paste powder was filled into a mold and pressurized at a pressure of 78 MPa along the axial direction to obtain cylindrical pellets of paste powder with a diameter of 8 mm.

[0059] Then, thermal analysis (TMA) was performed on the above pellets using a thermomechanical analyzer (TMA8310, manufactured by Rigaku Corporation). In the thermal analysis, the pellets were heated in an air atmosphere from room temperature to 800°C at a heating rate of 5°C / min. The change in length from 350°C to 800°C relative to the length of the pellet at 350°C (hereinafter also referred to as the "reference length") was defined as the shrinkage rate (%). In this thermal analysis, the temperature at which the shrinkage rate reached 1% was obtained when the pellets were showing a tendency to shrink. The results are shown in Table 1, "1% Shrinkage Temperature (°C)". Furthermore, the shrinkage rate (%) at 800°C was obtained. The results are shown in Table 1, "800°C Shrinkage Rate (%)". Furthermore, it was confirmed that the pellets showing a tendency to shrink did not change to an expansion tendency up to 800°C. The results are shown in the "Expansion" column of Table 1. Figure 2 shows the graph of the thermal analysis of this example. Figure 2 is the graph of the thermal analysis of Example 11. In Figure 2, the X-axis represents temperature, and the Y-axis represents the rate of contraction.

[0060] -Example 12- Titanium dioxide powder B was used instead of titanium dioxide powder A. Otherwise, the pellets for this example were prepared using the same materials and procedure as in Example 11, and the temperature at which a 1% shrinkage rate was observed, and the shrinkage rate at 800°C were calculated. It was confirmed that the pellets showing a tendency to shrink did not begin to expand by 800°C. The results are shown in the corresponding column of Table 1. Note that titanium dioxide powder B is spherical and has a specific surface area of ​​35 m². 2 / g~65m 2 The density is 4.3 g / cm³ / g. 3 The particle size ranged from 22 nm to 40 nm.

[0061] -Example 13- Silica powder A was used instead of titanium dioxide powder A. Otherwise, the pellets for this example were prepared using the same materials and procedure as in Example 11, and the temperature at which a 1% shrinkage rate was observed, and the shrinkage rate at 800°C were calculated. It was confirmed that the pellets, which were showing a tendency to shrink, began to show a tendency to expand by 800°C. The results are shown in the corresponding column of Table 1. Note that silica powder A is spherical and has a specific surface area of ​​50 m². 2 / g~70m 2The density is 2.7 g / cm³ / g. 3 The particle size was 32 nm to 45 nm.

[0062] -Example 14- Alumina powder was used instead of titanium dioxide powder A. Otherwise, the pellets for this example were prepared using the same materials and procedure as in Example 11, and the temperature at which a 1% shrinkage rate was observed, as well as the shrinkage rate at 800°C, were calculated. It was confirmed that the pellets, which were showing a tendency to shrink, began to show a tendency to expand by 800°C. The results are shown in the corresponding column of Table 1. Note that the alumina powder is spherical and has a specific surface area of ​​85 m². 2 / g~115m 2 The density is 4.0 g / cm³. 3 The particle size was between 13 nm and 18 nm.

[0063] -Example 15- Copper oxide powder was used instead of titanium dioxide powder A. Otherwise, the pellets for this example were prepared using the same materials and procedure as in Example 11, and the temperature at which a 1% shrinkage rate was observed, and the shrinkage rate at 800°C were calculated. It was confirmed that the pellets, which were showing a tendency to shrink, began to show a tendency to expand by 800°C. The results are shown in the corresponding column of Table 1. Note that the copper oxide powder is polyhedral and has a specific surface area of ​​10 m². 2 / g~30m 2 The density is 6.3 g / cm³ / g. 3 The particle size ranged from 32 nm to 95 nm.

[0064] -Example 16- Instead of titanium dioxide powder A, a milky white colloidal aqueous solution of zirconia was used. Otherwise, the pellets for this example were prepared using the same materials and procedures as in Example 11, and the temperature at which a 1% shrinkage rate was observed, and the shrinkage rate at 800°C were calculated. It was confirmed that the pellets, which were showing a tendency to shrink, began to show a tendency to expand by 800°C. The results are shown in the corresponding column of Table 1. Note that the D content of zirconia particles in the milky white colloidal aqueous solution of zirconia is... 50 The diameter ranged from 60 nm to 105 nm.

[0065] -Example 17- Except for not using titanium dioxide powder A, the pellets for this example were prepared using the same materials and procedure as in Example 11, and the temperature at which a 1% shrinkage rate was observed, and the shrinkage rate at 800°C were calculated. It was confirmed that the pellets, which were showing a tendency to shrink, began to show a tendency to expand by 800°C. The results are shown in the corresponding column of Table 1. Figure 3 is a graph of the thermal analysis of Example 17. In Figure 3, the X axis is temperature and the Y axis is shrinkage rate.

[0066] A negative shrinkage rate (%) indicates that the pellet, when heated to 800°C, has shrunk relative to its standard length. A positive shrinkage rate (%) indicates that the pellet, when heated to 800°C, has expanded relative to its standard length. When the 1% shrinkage temperature (°C) is in the range of 350°C to 800°C and the shrinkage rate (%) is positive, it indicates that the pellet initially shrinks upon heating, but then expands within the 350°C to 800°C range (see Figure 3). The same explanation applies to Tables 1 to 4.

[0067] [Table 1]

[0068] As shown in Table 1, comparing Examples 11 and 12 with Examples 13-17, in Examples 11 and 12, the 1% shrinkage temperature of the pellets was higher, and at 800°C, the pellets were in a contracted state. Furthermore, in thermal analysis up to 800°C, in Examples 11 and 12, the pellets did not shift from a tendency to shrink to a tendency to expand, but in Examples 13-17, the pellets shifted from a tendency to shrink to a tendency to expand. As described above, the silver pastes prepared in Examples 11 and 12 contained silver powder, a resin binder, an organic solvent, and titanium dioxide powder. The silver powder was D 50 The diameter was at least 1 μm. The titanium dioxide powder consisted of spherical titanium dioxide particles.

[0069] -Example 111- The content ratio of titanium dioxide powder A in the silver paste was set to 2.5×10 -3 mass% (25 ppm), and the content ratio of the organic solvent was adjusted. In the silver paste, 2.6×10 -3 parts by mass of titanium dioxide powder A was contained per 100 parts by mass of silver powder A. Otherwise, using the same materials and procedures as in Example 11, the pellets of this example were prepared, and the temperature showing a shrinkage rate of 1% and the shrinkage rate at 800 °C were calculated. It was confirmed that the pellets having a shrinkage tendency did not turn into an expansion tendency by 800 °C. The results are shown in the corresponding column of Table 2.

[0070] -Example 112- The content ratio of titanium dioxide powder A in the silver paste was set to 5.0×10 -3 mass% (50 ppm), and the content ratio of the organic solvent was adjusted. In the silver paste, 5.3×10 -3 parts by mass of titanium dioxide powder A was contained per 100 parts by mass of silver powder A. Otherwise, using the same materials and procedures as in Example 11, the pellets of this example were prepared, and the temperature showing a shrinkage rate of 1% and the shrinkage rate at 800 °C were calculated. It was confirmed that the pellets having a shrinkage tendency did not turn into an expansion tendency by 800 °C. The results are shown in the corresponding column of Table 2.

[0071] -Example 113- The content ratio of titanium dioxide powder A in the silver paste was set to 7.5×10 -3 mass% (75 ppm), and the content ratio of the organic solvent was adjusted. In the silver paste, 7.9×10 -3 parts by mass of titanium dioxide powder A was contained per 100 parts by mass of silver powder A. Otherwise, using the same materials and procedures as in Example 11, the pellets of this example were prepared, and the temperature showing a shrinkage rate of 1% and the shrinkage rate at 800 °C were calculated. It was confirmed that the pellets having a shrinkage tendency did not turn into an expansion tendency by 800 °C. The results are shown in the corresponding column of Table 2.

[0072] -Example 114- The content ratio of titanium dioxide powder A in the silver paste was set to 1.5×10 -2The concentration was adjusted to 150 ppm by mass, and the proportion of organic solvent was adjusted. In the silver paste, 1.6 × 10¹⁶ parts by mass of silver powder A -2 The pellets in this example were prepared using the same materials and procedures as in Example 11, and the temperature at which a 1% shrinkage rate was observed, as well as the shrinkage rate at 800°C, were calculated. The results are shown in the corresponding columns of Table 2.

[0073] -Example 115- The content of titanium dioxide powder A in the silver paste was set to 0.03% by mass (300 ppm), and the content of the organic solvent was adjusted. In the silver paste, 3.2 × 10¹⁶ parts per 100 parts by mass of silver powder A -2 The pellets in this example were prepared using the same materials and procedures as in Example 11, and the temperature at which a 1% shrinkage rate was observed, as well as the shrinkage rate at 800°C, were calculated. It was confirmed that the pellets, which were showing a tendency to shrink, did not begin to expand by 800°C. The results are shown in the corresponding column of Table 2.

[0074] [Table 2]

[0075] Table 2 shows the results for Example 11 and Example 17 together for reference. As shown in Table 2, comparing Examples 11 and 111-115 with Example 17, it was found that in Examples 11 and 111-115, which contain titanium dioxide powder (in this case, titanium dioxide powder A) in the silver paste, the 1% shrinkage temperature of the pellets was higher than in Example 17, which does not contain titanium dioxide powder, and the pellets contracted at 800°C. Furthermore, the results for Examples 11 and 111-115 showed that the 1% shrinkage temperature of the pellets increased in a manner dependent on the titanium dioxide powder content. In addition, in thermal analysis up to 800°C, the pellets in Examples 11 and 111-115 did not shift from a tendency to shrink to a tendency to expand.

[0076] <Exam 2> -Example 21- Silver powder B was prepared. When the particle size distribution of silver powder B was analyzed, the D 10 diameter was 2.6 μm, and the D 50 diameter was 6.7 μm, and the D 90 diameter was 27 μm. For the analysis of the particle size distribution of the silver powder, "MT3300EX" of Microtrac was used. The temperature was raised up to 900 °C in the thermal analysis. Otherwise, using the same materials and procedures as in Example 11, the pellets of this example were produced, and the temperature showing a shrinkage rate of 1% and the shrinkage rate at 800 °C were calculated. The results are shown in the corresponding columns of Table 3. Furthermore, the temperature at which the pellet changes from a shrinkage tendency to an expansion tendency was obtained. The results are shown in "Inversion temperature (°C)" of Table 3. FIG. 4 is a graph when Example 21 was thermally analyzed. In FIG. 4, the X-axis is the temperature and the Y-axis is the shrinkage rate.

[0077] - Example 22 - Titanium dioxide powder A and silica powder B were included in the silver paste. Silica powder B was spherical, had a specific surface area of 75 m 2 / g to 105 m 2 / g, had a density of 2.7 g / cm 3 , and had a particle diameter of 22 nm to 30 nm. The content ratio of titanium dioxide powder A in the silver paste was 5.0×10 -3 mass% (50 ppm), the content ratio of silica powder B in the silver paste was 5.0×10 -3 mass% (50 ppm), and the content ratio of the organic solvent was adjusted. In the silver paste, 5.3×10 -3 mass parts of titanium dioxide powder A and 5.3×10 -3 mass parts of silica powder B were included per 100 mass parts of silver powder B. Otherwise, using the same materials and procedures as in Example 21, the pellets of this example were produced, and the temperature showing a shrinkage rate of 1%, the shrinkage rate at 800 °C, and the inversion temperature were calculated. The results are shown in the corresponding columns of Table 3. FIG. 5 is a graph when Example 22 was thermally analyzed. In FIG. 5, the X-axis is the temperature and the Y-axis is the shrinkage rate.

[0078] - Example 23 - The silver paste contained titanium dioxide powder A and the alumina powder mentioned above. The content ratio of titanium dioxide powder A in the silver paste was 5.0 × 10⁻⁶. -3 Assuming mass % (50 ppm), the alumina powder content in the silver paste is 5.0 × 10 -3 The concentration was set to mass% (50 ppm), and the proportion of organic solvent was adjusted. In the silver paste, 5.3 × 10 parts per 100 parts by mass of silver powder A -3 The mass of titanium dioxide powder A and 5.3 × 10 -3 The material contained alumina powder by mass. Otherwise, the pellets for this example were prepared using the same materials and procedure as in Example 21, and the temperature at which a 1% shrinkage rate occurred, the shrinkage rate at 800°C, and the inversion temperature were calculated. The results are shown in the corresponding column of Table 3. Figure 6 is a graph of the thermal analysis of Example 23. In Figure 6, the X axis is temperature and the Y axis is shrinkage rate.

[0079] -Example 24- Except for not including titanium dioxide powder A in the silver paste, the pellets of this example were prepared using the same materials and procedure as in Example 21, and the temperature at which a 1% shrinkage rate was observed, the shrinkage rate at 800°C, and the inversion temperature were calculated. The results are shown in the corresponding column of Table 3. Figure 7 is a graph of the thermal analysis of Example 24. In Figure 7, the X axis is temperature and the Y axis is shrinkage rate.

[0080] [Table 3]

[0081] As shown in Table 3, comparing Example 21 and Example 24, it was found that in Examples 21 to 23, which contain titanium dioxide powder (in this case, titanium dioxide powder A) in the silver paste, the 1% shrinkage temperature of the pellets was higher than in Example 24, which does not contain titanium dioxide powder, and the pellets contracted at 800°C, and the reversal temperature (°C) was also higher. Furthermore, the results for Examples 22 and 23 showed that the pellets did not change from a tendency to contract to a tendency to expand in the temperature range up to 900°C.

[0082] -Example 221- The silver paste contained titanium dioxide powder A and silica powder B. The content ratio of titanium dioxide powder A in the silver paste was 2.5 × 10⁻⁶. -3 Assuming a mass percentage (25 ppm), the content of silica powder B in the silver paste is 7.5 × 10 -3 The concentration was adjusted to 75 ppm by mass, and the proportion of organic solvent was adjusted. In the silver paste, 2.6 × 10¹⁶ parts by mass of silver powder A -3 Titanium dioxide powder A by mass, and 7.9 × 10 -3 The pellets in this example were prepared using the same materials and procedures as in Example 21, and the temperature at which a 1% shrinkage rate was observed, the shrinkage rate at 800°C, and the inversion temperature were calculated. The results are shown in the corresponding columns of Table 4.

[0083] -Example 222- The silver paste contained titanium dioxide powder A and silica powder B. The content ratio of titanium dioxide powder A in the silver paste was 7.5 × 10⁻⁶. -3 Assuming a mass percentage (75 ppm), the content of silica powder B in the silver paste is 2.5 × 10⁻⁶. -3 The concentration was adjusted to 25 ppm by mass, and the proportion of organic solvent was adjusted. In the silver paste, 7.9 × 10¹⁶ parts by mass of silver powder A -3 Titanium dioxide powder A by mass, and 2.6 × 10 -3 The pellets in this example were prepared using the same materials and procedures as in Example 21, and the temperature at which a 1% shrinkage rate was observed, the shrinkage rate at 800°C, and the inversion temperature were calculated. The results are shown in the corresponding columns of Table 4.

[0084] -Example 223- Silica powder B was added to the silver paste. The content of silica powder B in the silver paste was set to 0.01% by mass (100 ppm), and the content of the organic solvent was adjusted. In the silver paste, 1.1 × 10¹⁶ parts by mass of silver powder A were added. -2The pellets in this example were prepared using the same materials and procedures as in Example 21, and the temperature at which a 1% shrinkage rate occurred, the shrinkage rate at 800°C, and the inversion temperature were calculated. The results are shown in the corresponding columns of Table 4.

[0085] [Table 4]

[0086] Table 4 includes, for reference, the results for Example 21, Example 22, and Example 24. As shown in Table 4, in Examples 221, 22, and 222, which contain titanium dioxide powder and silica powder in the silver paste, the pellets did not shift from shrinking to expanding in the temperature range up to 900°C.

[0087] The technologies disclosed herein may include the following: Section 1: An internal electrode paste used for forming internal electrodes of multilayer ceramic electronic components, In a volume-based particle size distribution based on laser diffraction scattering, D corresponds to 50% of the cumulative value from the smallest particle size. 50 Silver powder with a diameter of at least 1 μm, resin binder and Organic solvents and Titanium dioxide powder composed of spherical titanium dioxide particles, A paste for internal electrodes, including [specific component]. Section 2: D in the particle size distribution of the silver powder 10 The internal electrode paste described in item 1 has a diameter of 1 μm or more and 3 μm or less. Section 3: D in the particle size distribution of the silver powder 90 The internal electrode paste described in item 1 or 2 has a diameter of 10 μm or more and 15 μm or less. Section 4: Per 100 parts by mass of the aforementioned silver powder, 1.0 × 10 -3 Mass part or more 5.0×10 -2A paste for internal electrodes according to any one of items 1 to 3, comprising the titanium dioxide powder in parts by mass or less. Section 5: Furthermore, the paste for internal electrodes according to any one of claims 1 to 4, comprising other oxide powders different from the titanium dioxide powder. Item 6: The paste for internal electrodes according to item 5, wherein the other oxide powder comprises at least one of alumina and silica. Section 7: The paste for internal electrodes according to item 5 or 6, wherein the mass ratio of the titanium dioxide powder to the other oxide powder (titanium dioxide powder:other oxide powder) is 1:9 or more and 9:1 or less. Section 8: With respect to 100 parts by mass of the aforementioned silver powder, 1.0 × 10 -3 Mass part or more 1.0×10 -2 The titanium dioxide powder in parts by mass or less, 1.0 × 10 -3 Mass part or more 1.0×10 -2 The other oxide powders in amounts less than or equal to parts by mass, A paste for internal electrodes, including any of the items 5 to 7. Section 9: A method for manufacturing a multilayer ceramic electronic component, comprising applying an internal electrode paste described in any of items 1 to 8 to a substrate, and firing the coating film of the internal electrode paste and the substrate. [Explanation of symbols]

[0088] 1. Multilayer chip inductor 10 Main Unit 12 Magnetic layer 14 Internal electrode layer 20 External electrode

Claims

1. An internal electrode paste used for forming internal electrodes of multilayer ceramic electronic components, In a volume-based particle size distribution based on laser diffraction scattering, D corresponds to 50% of the cumulative value from the smallest particle size. ５０ Silver powder having a diameter of at least 1 μm, resin binder and Organic solvents and Titanium dioxide powder composed of spherical titanium dioxide particles, A paste for internal electrodes, including [specific component].

2. D in the particle size distribution of the silver powder １０ The internal electrode paste according to claim 1, wherein the diameter is 1 μm or more and 3 μm or less.

3. D in the particle size distribution of the silver powder ９０ The internal electrode paste according to claim 2, wherein the diameter is 10 μm or more and 15 μm or less.

4. Per 100 parts by mass of the aforementioned silver powder, 1.0 × 10 －３ Mass parts or more 5.0 x 10 －２ The paste for internal electrodes according to claim 1, comprising the titanium dioxide powder in parts by mass or less.

5. Furthermore, the paste for internal electrodes according to claim 1, further comprising other oxide powders different from the titanium dioxide powder.

6. The paste for internal electrodes according to claim 5, wherein the other oxide powder comprises at least one of alumina and silica.

7. The paste for internal electrodes according to claim 5, wherein the mass ratio of the titanium dioxide powder to the other oxide powder (titanium dioxide powder: other oxide powder) is 1:9 or more and 9:1 or less.

8. With respect to 100 parts by mass of the aforementioned silver powder, 1.0 x 10 －３ Mass part or more 1.0×10 －２ The titanium dioxide powder in parts by mass or less, 1.0×10 －３ parts by mass or more of 1.0×10 －２ parts by mass or less of the other oxide powder, and The paste for internal electrodes according to claim 5, including the above.

9. A method for manufacturing a multilayer ceramic electronic component, comprising applying an internal electrode paste according to any one of claims 1 to 8 to a substrate, and firing the coating film of the internal electrode paste and the substrate.

Images