Multilayer ceramic electronic components, conductive materials, and methods for manufacturing multilayer ceramic electronic components.

Abstract

Provided is a multilayer ceramic electronic component having improved conductivity of an external electrode provided on a surface of a ceramic element and having excellent contacting properties with an internal electrode disposed in the interior of the ceramic element.　The external electrode includes a conductive metal and silicon-containing glass. The conductive metal includes silver and copper, the silver component being larger in volume ratio than the copper component. The silver and copper are present in the states of silver particles (11), copper particles (12), and bonded particles (13) obtained by bonding the silver particles (11) and copper particles (12). The bonded particles (13) have a flat shape, and other than the surfaces of the bonded particles (13) where the silver particles (11) and copper particles (12) are bonded together, copper is not present on the surface of the silver particles (11) and silver is not present on the surface of the copper particles (12). A portion of the copper included in the external electrode is diffused to the internal electrode.

Description

Technical Field

[0001] The present invention relates to a multilayer ceramic electronic component, a conductive material, and a method for manufacturing a multilayer ceramic electronic component, and particularly relates to a structure of an external electrode provided on a surface of a ceramic body included in a multilayer ceramic electronic component, a conductive material for forming the external electrode, and a method for manufacturing a multilayer ceramic electronic component implemented using the conductive material.

Background Art

[0002] As a technology of interest to the present invention, for example, Japanese Patent No. 6056388 (Patent Document 1) describes a method for manufacturing a multilayer ceramic capacitor. In the technology described in Patent Document 1, in order to thin the external electrode, a metal oxide precursor solution such as a sol-gel material or a MOD material that becomes a metal oxide through heat treatment is used. By using the metal oxide precursor solution, the coating amount applied to the ceramic body can be reduced, and as a result, the external electrode can be thinned.

[0003] The metal oxide film precipitates metal through reduction heat treatment. This metal serves as a base metal film for ensuring contact with an internal electrode. Microscopically, this base metal film is a film-like aggregate in which a large number of metal particles adhere to each other. The particle size of the metal particles is approximately 0.1 to 1 µm, and therefore, the thickness of the base metal film is 0.1 to 1.0 µm on any surface to which the solution is applied. The material of the metal particles is, for example, Cu, Ni, W, Mo, Nb, Ta, Ti, or Zr.

[0004] To form the base metal film, for example, a solution obtained by mixing a CuO coating solution and an ITO coating solution at a ratio of 7:3 is used. This solution is heat-treated in air at 480°C for 40 minutes to oxidize the metal compound, and then heat-treated in a reducing atmosphere at 450°C for 40 minutes to reduce part of the metal oxide.

[0005] In the technology described in Patent Document 1, a sealing metal film with a density higher than the underlying metal film is formed to prevent the plating solution from penetrating through the underlying metal film. The material of the sealing metal film is, for example, Cu, Ni, W, Mo, Nb, Ta, Ti, or Zr. Since it is preferable for the sealing metal film to be thicker than the underlying metal film, it is formed by sputtering, vapor deposition, or CVD, which allow for easy control of the film thickness. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Patent No. 6056388 [Overview of the project] [Problems that the invention aims to solve]

[0007] In the technology described in Patent Document 1, the underlying metal layer is presumed to contain ITO and CuO, which remains partially as a result of the reduction deposition of Cu. Therefore, the underlying metal layer has many gaps between particles and is low in density, resulting in poor conductivity and insufficient sealing properties against plating solutions and water vapor. Forming a sealing metal film to address the sealing problem not only hinders the thinning of the external electrode but also leads to an increase in the number of steps.

[0008] Furthermore, it is considered that films with a thickness of 0.1 to 1.0 μm obtained by applying the materials and heat treatment described in Patent Document 1 have insufficient contact with internal electrodes containing Ni or the like as conductive components.

[0009] Therefore, the object of this invention is to provide a multilayer ceramic electronic component that improves the conductivity of external electrodes provided on the surface of a ceramic body and has excellent contact properties with internal electrodes arranged inside the ceramic body, as well as to provide a conductive material for forming external electrodes and a method for manufacturing a multilayer ceramic electronic component using this conductive material. [Means for solving the problem]

[0010] In order to solve the technical problems described above, this invention provides an improved structure for the external electrodes in a multilayer ceramic electronic component, a conductive material for forming such an improved external electrode, and a method for manufacturing a multilayer ceramic electronic component using this conductive material.

[0011] The ceramic electronic component according to this invention comprises a ceramic body having a plurality of stacked ceramic layers and internal electrodes arranged along the interfaces between the ceramic layers, and an external electrode provided on the surface of the ceramic body and electrically connected to the internal electrodes.

[0012] The external electrode contains a conductive metal and a silicon-containing glass. The conductive metal contains silver and copper, with the silver component being more abundant than the copper component by volume. The silver and copper exist in the form of silver particles, copper particles, and bonded particles formed by the bonding of silver and copper particles. The bonded particles are flattened, and copper is absent from the surface of the silver particles and silver from the surface of the copper particles, except at the bonding surface between the silver and copper particles. Furthermore, some of the copper contained in the external electrode diffuses into the internal electrode.

[0013] The conductive material according to this invention comprises a conductive metal salt in a sol state that becomes a conductive metal as a conductive component when fired, a glass raw material containing a glass metal salt that becomes a silicon-containing glass when fired, and a solvent for dissolving or dispersing the conductive metal salt and the glass raw material. The ratio of the content of the glass raw material to the content of the conductive metal salt is 0.04 or more and 1.40 or less, converted to the mass of the conductive metal salt after metallization and the mass of the glass raw material after vitrification. The conductive metal salt includes a silver salt and a copper salt, and the ratio of the volume of the silver salt after metallization to the volume of the copper salt after metallization is greater than 1.

[0014] A method for manufacturing a multilayer ceramic electronic component according to this invention is a method for manufacturing a multilayer ceramic electronic component comprising a ceramic body having a plurality of stacked ceramic layers and internal electrodes arranged along the interfaces between the ceramic layers, and external electrodes provided on the surface of the ceramic body and electrically connected to the internal electrodes, characterized by comprising the steps of: applying the conductive material according to this invention to the surface of the ceramic body so as to be in contact with the internal electrodes; heating and drying the applied conductive material at a temperature of 145°C or higher; and then firing the conductive material to form the external electrodes. [Effects of the Invention]

[0015] According to the multilayer ceramic electronic component of this invention, since a portion of the copper in the external electrode diffuses into the internal electrode, good contact can be obtained between the external electrode and the internal electrode. Furthermore, in the external electrode, the silver does not diffuse into the internal electrode, and some of the silver particles bond with the copper particles, forming flattened bonded particles that are easily in contact with each other. Therefore, good conductivity and good plating adhesion can be achieved within the external electrode.

[0016] According to the conductive material of this invention, since it contains more silver than copper by volume, when fired, flattened bonded particles in which silver particles and copper particles are joined together are easily formed. Therefore, a state in which particles can easily come into contact with each other is obtained, and good conductivity can be obtained in a conductive film such as an external electrode formed with this conductive material. Furthermore, since the conductive material is in a sol state, as gelation and vitrification progress due to heat treatment, the solvent and reaction by-products are removed, so volume shrinkage occurs in the thickness direction in a conductive film such as an external electrode formed with this conductive material, which is advantageous for thinning the conductive film.

[0017] According to the method for manufacturing a multilayer ceramic electronic component according to the present invention, heating and drying the conductive material described above at a temperature of 145° C. or higher allows silver particles to be precipitated before firing, so that silver particles can be grown before bonding between silver particles and copper particles in the firing step. This is advantageous for growing flat bonded particles and forming a thinned external electrode. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] [Figure 1] It is a cross-sectional view schematically showing a multilayer ceramic capacitor 1 as a multilayer ceramic electronic component according to an embodiment of the present invention. [Figure 2] It is an enlarged cross-sectional view schematically showing a portion where the external electrode 6 of the multilayer ceramic capacitor 1 shown in FIG. 1 is provided. [Figure 3] It is a view showing a STEM image of a cross-section of an external electrode of a multilayer ceramic capacitor according to an example produced in an experimental example. [Figure 4] It is a view showing an EDX image of a cross-section of the external electrode shown in FIG. 3. [Figure 5] It is a view in which an Ag region is emphasized in the EDX image shown in FIG. 4. [Figure 6] It is a view in which a Cu region is emphasized in the EDX image shown in FIG. 4. [Figure 7] It is a view showing a STEM image of a cross-section of an external electrode of a multilayer ceramic capacitor according to Comparative Example 1 produced in an experimental example. [Figure 8] It is a view showing an EDX image of a cross-section of the external electrode shown in FIG. 7. [Figure 9] It is a view in which an Ag region is emphasized in the EDX image shown in FIG. 8. [Figure 10] It is a view in which a Cu region is emphasized in the EDX image shown in FIG. 8. [Figure 11] It is a view showing a STEM image of a cross-section of an external electrode of a multilayer ceramic capacitor according to Comparative Example 2 produced in an experimental example. [Figure 12] It is a view showing an EDX image of a cross-section of the external electrode shown in FIG. 11. [Modes for carrying out the invention]

[0019] Referring to Figure 1, the structure of a multilayer ceramic capacitor 1 as a multilayer ceramic electronic component according to one embodiment of this invention will be described.

[0020] The multilayer ceramic capacitor 1 comprises a ceramic body 2. The ceramic body 2 comprises a plurality of stacked ceramic layers 3 and a plurality of internal electrodes 4 and 5 arranged along the interfaces between the plurality of ceramic layers 3. The internal electrodes 4 and 5 are classified into a plurality of first internal electrodes 4 and a plurality of second internal electrodes 5, which are alternately arranged in the stacking direction of the ceramic body 2. A first external electrode 6 and a second external electrode 7 are provided on the surface of the ceramic body 2, more specifically on each of the opposing end faces. The first external electrode 6 is electrically connected to the first internal electrode 4, and the second external electrode 7 is electrically connected to the second internal electrode 5.

[0021] The ceramic layer 3 is made of a dielectric ceramic mainly composed of ABO3 (where A is at least one of Ba, Ca, and Sr, and B is at least one of Ti and Zr). The dielectric ceramic may also mainly consist of the above ABO3 and further contain at least one of Mn, Mg, Si, Y, Dy, and Gd as a minor component.

[0022] The internal electrodes 4 and 5 contain a conductive metal or an alloy containing the same as a conductive component, for example, one selected from nickel, copper, silver, and silver / palladium alloys, and it is particularly preferable that they contain nickel.

[0023] External electrodes 6 and 7 are formed by applying a conductive material, described later, to the end faces of the ceramic body 2 so as to be in contact with the respective ends of the internal electrodes 4 and 5, and then firing it. In Figure 2, a portion of the first external electrode 6 is shown in a cross-sectional view. The second external electrode 7 is not shown in Figure 2, but has substantially the same configuration as the first external electrode 6. Therefore, only the first external electrode 6 will be described, and the description of the second external electrode 7 may be omitted. A plating film 8 (not shown in Figure 1) is formed on the external electrodes 6 and 7.

[0024] External electrodes 6 and 7 contain a conductive metal and a silicon-containing glass, and the conductive metal contains silver and copper, with the silver component being more abundant than the copper component by volume. The structure of external electrodes 6 and 7 will be explained with reference to the cross-sectional images of the external electrodes of the multilayer ceramic capacitors fabricated in the experimental examples described later. Figure 3 shows a STEM image of the cross-section of the external electrode, and Figure 4 shows an EDX image of the cross-section of the external electrode shown in Figure 3. Furthermore, Figure 5 is an EDX image from Figure 4 with the Ag region emphasized, and Figure 6 is an EDX image from Figure 4 with the Cu region emphasized.

[0025] In particular, in Figure 4, the silver particles 11 appear as white granular regions, and the copper particles 12 appear as gray granular regions. Furthermore, in Figure 5, the regions where silver particles 11 are present are highlighted in white, and in Figure 6, the regions where copper particles 12 are present are highlighted in white.

[0026] Referring to Figures 3 to 6, in the external electrode, silver and copper exist in the following states: silver particles 11, copper particles 12, and bonded particles 13 formed by the bonding of silver particles 11 and copper particles 12. The bonded particles 13 are flattened. Except for the bonding surface between the silver particles 11 and copper particles 12 in the bonded particles 13, copper is not present on the surface of the silver particles 11, and silver is not present on the surface of the copper particles 12.

[0027] Although not shown in Figures 3 through 6, as schematically shown in Figure 2, some of the copper contained in the external electrode 6 diffuses into the internal electrode 4. In this way, some of the copper in the external electrodes 6 and 7 diffuses into the internal electrodes 4 and 5, so good contact can be obtained between the external electrodes 6 and 7 and the internal electrodes 4 and 5.

[0028] Furthermore, in the external electrodes 6 and 7, the silver does not diffuse into the internal electrodes 4 and 5. As described above, some of the silver particles 11 bond with the copper particles 12, forming flattened bonded particles 13, which are in a state where they can easily come into contact with each other. Therefore, good conductivity and good plating adhesion can be achieved within the external electrodes 6 and 7.

[0029] A multilayer ceramic capacitor 1 is manufactured, for example, through the following process. First, a ceramic slurry containing ceramic raw material powder having the above composition is prepared. Next, a suitable sheet molding method is applied to the ceramic slurry to form a ceramic green sheet. Next, conductive pastes that will become the internal electrodes 4 and 5 are applied to a predetermined ceramic green sheet from among several ceramic green sheets by printing or other means. Next, the multiple ceramic green sheets are laminated and then pressed together to obtain a raw ceramic body. Next, the raw ceramic body is fired. In this firing process, the ceramic green sheets become the ceramic layer 3. After that, a process is carried out to form external electrodes 6 and 7 on the end face of the ceramic body 2, and then a process is carried out to form a plating film 8 on the external electrodes 6 and 7.

[0030] The conductive material for forming the external electrodes 6 and 7 comprises a conductive metal salt that becomes a conductive metal as a conductive component when fired, a glass raw material containing a glass metal salt that becomes a silicon-containing glass when fired, and a solvent for dissolving or dispersing the conductive metal salt and the glass raw material. The ratio of the content of the glass raw material to the content of the conductive metal salt is 0.04 or more and 1.40 or less, converted to the mass of the conductive metal salt after metallization and the mass of the glass raw material after vitrification. The conductive metal salt includes a silver salt and a copper salt, and the ratio of the volume of the silver salt after metallic silverization to the volume of the copper salt after metallic copperization is greater than 1.

[0031] Such conductive materials are initially in a sol state, applied to opposing end faces of the ceramic substrate 2, and then heated and dried to form a gel state, after which the above glass S The glass raw materials are fired at a temperature above the softening point and below the melting point, causing them to vitrify.

[0032] In the aforementioned heating and drying process, a temperature of 145°C or higher is applied. This allows silver particles to precipitate before firing, thus enabling the growth of silver particles before they bond with copper particles during the firing process. This is advantageous for the growth of flattened bonding particles and the formation of thin-film external electrodes.

[0033] Since temperatures of 145°C or higher are applied during the heating and drying process, it is preferable that the solvent contained in the conductive material has a boiling point of 145°C or lower. For example, 2-methoxyethanol is advantageously used as the solvent.

[0034] Furthermore, since the conductive material contains more silver than copper by volume, when fired, flattened bonded particles 13, in which silver particles 11 and copper particles 12 are joined together, are easily formed. Therefore, a state is obtained where the particles can easily come into contact with each other, and good conductivity can be obtained in the external electrodes 6 and 7 formed with this conductive material. In addition, the conductive material is initially in a sol state, and as gelation and vitrification progress due to heat treatment, the solvent and reaction by-products are removed, so volume shrinkage occurs in the thickness direction in the external electrodes 6 and 7 formed with this conductive material, which is advantageous for thin film formation.

[0035] The glass raw materials included in the conductive material described above preferably contain nanosilica and boric acid in addition to the metal salts for glass mentioned above.

[0036] Metal salts used as raw materials for glass include, for example, lithium nitrate and sodium nitrate.

[0037] The silver salt contained in the conductive material includes, for example, either silver carboxylate or silver nitrate, and the copper salt includes, for example, either copper carboxylate or copper nitrate.

[0038] The conductive material may contain an organic binder for viscosity adjustment or other purposes. Hydroxypropyl cellulose is an advantageous example of the organic binder.

[0039] The plating film 8 formed on the external electrodes 6 and 7 is not shown in detail, but for example, it consists of a Cu plating layer, a Ni plating layer on top of it, and a Sn plating layer on top of that.

[0040] Although this invention has been described above in relation to the external electrodes of a multilayer ceramic capacitor, this invention can also be applied to multilayer ceramic electronic components other than multilayer ceramic capacitors, as long as they include a multilayer ceramic body having a multilayer structure with a plurality of stacked ceramic layers and internal electrodes arranged along the interfaces between the ceramic layers, and the surface of the ceramic body is provided with external electrodes electrically connected to the internal electrodes.

[0041] Next, we will describe experimental examples conducted to confirm the effects of this invention.

[0042] [Examples] <Fabrication of conductive materials> A sol-state conductive material containing the following (1) to (8) was prepared. (1) Tetraethoxysilane: 2.23% by mass, (2) Boric acid: 0.38% by mass, (3) Lithium nitrate (melting point: 260°C): 0.20% by mass, (4) Sodium nitrate (melting point: 306°C): 0.27% by mass, (5) Silver nitrate: 7.60% by mass, (6) Copper(II) nitrate trihydrate: 11.02% by mass, (7) Hydroxypropylcellulose (2.0~2.9 @ 20℃ / 2% aqueous solution): 11.60% by mass, (8) 2-Methoxyethanol: 54.71% by mass.

[0043] Items (1) to (4) above are glass raw materials that become glass when fired, and (3) and (4) are metal salts for glass. (5) is a silver salt that becomes silver when fired. (6) is a copper salt that becomes copper when fired. (7) is an organic binder. (8) is a solvent.

[0044] The composition of the conductive material used in the examples is also shown in Table 1 below.

[0045] <Coating and baking> For a multilayer ceramic capacitor (0.6 mm × 0.3 mm × 0.3 mm) with Ni internal electrodes, the end face of the ceramic substrate was immersed in the sol-like conductive material described above, and then the conductive material was dried at 150°C for 10 minutes to gel. The opposite end face of the ceramic substrate was similarly immersed and dried.

[0046] Next, hydrogen gas is introduced into N2, S The material was fired at 700°C, above its softening point and below its melting point, to form the external electrode.

[0047] <Structural analysis of external electrodes> Structural analysis was performed on the external electrode sample at the center of the planes extending in the width and thickness directions of the multilayer ceramic capacitor using STEM (Hitachi High-Tech Scanning Electron Microscope "HD-2300A") and EDX (EDAX Energy Dispersive X-ray Spectrometer "Genesis XM4"). As a result, the STEM image shown in Figure 3 and the EDX images shown in Figures 4 to 6 were obtained. Figure 5 is an enhanced Ag region in the EDX image shown in Figure 4, and Figure 6 is an enhanced Cu region in the EDX image shown in Figure 4.

[0048] In Figures 3 to 6, representative examples of the silver particles 11, copper particles 12, and bonded particles 13 formed by the bonding of the silver particles 11 and copper particles 12 are denoted by the reference numerals "11," "12," and "13," respectively.

[0049] As shown in Figures 3 to 6, flattened bonded particles 13 were observed in which silver particles 11 and copper particles 12 were joined together. Furthermore, it was confirmed that, apart from the bonding surface between the silver particles 11 and copper particles 12 in the bonded particles 13, copper was not present on the surface of the silver particles 11, and silver was not present on the surface of the copper particles 12.

[0050] <plating> Electrolytic Cu, Ni, and Sn plating were sequentially performed on the external electrodes under the following conditions to form a plating film.

[0051] (Cu plating conditions) Plating bath type: Cu pyrophosphate plating bath (pH=8.6) ·Bath temperature: 55℃, • Current value: 10A Plating time: 90 minutes.

[0052] (Ni plating conditions) Plating bath type: Watt bath (pH=4.0) ·Bath temperature: 60℃, • Current value: 6A Plating time: 51 minutes.

[0053] (Sn plating conditions) • Plating bath type: Neutral plating bath (pH=6.0) ·Bath temperature: 25℃, • Current value: 3A Plating time: 66 minutes.

[0054] <Evaluation of the bonding between the internal and external electrodes> The obtained multilayer ceramic capacitor samples were dried at 150°C for 1.5 hours, left to stand for 24 hours, and then the capacitance and dielectric loss tangent were measured.

[0055] Next, a voltage of 25V was applied to each sample for 5 seconds, and then the sample was dropped onto a stainless steel plate to induce a discharge (0Ω discharge). This was repeated 5 times.

[0056] Subsequently, the samples were dried at 150°C for 1.5 hours and left to stand for 24 hours before measuring capacitance and dielectric loss tangent. Twenty samples were used.

[0057] These results are shown in Table 1 below.

[0058] [Comparative Example 1] <Fabrication of conductive materials> As shown in Table 1, a sol-state conductive material was prepared in the same manner as in the examples, except that the ratio of silver nitrate to copper(II) nitrate trihydrate was changed.

[0059] <Coating and baking> The conductive material was coated, dried, and fired in the same manner as in the examples.

[0060] <Structural analysis of external electrodes> Structural analysis of the external electrode was performed, similar to the example.

[0061] As a result, we obtained the STEM image shown in Figure 7 and the EDX images shown in Figures 8 to 10. Figure 9 is an enhanced version of the EDX image shown in Figure 8, emphasizing the Ag region, and Figure 10 is an enhanced version of the EDX image shown in Figure 8, emphasizing the Cu region.

[0062] In Figures 7 through 10, representative silver particles 11 and copper particles 12 are denoted by the reference numerals "11" and "12," respectively.

[0063] As shown in Figures 7 to 10, in Comparative Example 1, the growth of flattened particles did not progress as much as in the Example.

[0064] <plating> Plating was performed in the same manner as in the example.

[0065] <Evaluation of the bonding between the internal and external electrodes> The evaluation was carried out in the same manner as in the examples. The results are shown in Table 1 below.

[0066] [Comparative Example 2] <Fabrication of conductive materials> As shown in Table 1, a sol-state conductive material was prepared in the same manner as in the examples, except that it did not contain silver nitrate.

[0067] <Coating and baking> The conductive material was coated, dried, and fired in the same manner as in the examples.

[0068] <Structural analysis of external electrodes> Structural analysis of the external electrode was performed, similar to the example.

[0069] As a result, we obtained the STEM image shown in Figure 11 and the EDX image shown in Figure 12. In Figures 11 and 12, representative copper particles 12 are denoted with the reference numeral "12".

[0070] As shown in Figures 11 and 12, in Comparative Example 2, the growth of flattened particles did not progress as much as in the Example.

[0071] <plating> Plating was performed in the same manner as in the example.

[0072] <Evaluation of the bonding between the internal and external electrodes> The evaluation was carried out in the same manner as in the examples. The results are shown in Table 1.

[0073] [Table 1]

[0074] In the examples, the coefficient of variation of capacitance before and after 0Ω discharge, the dielectric loss tangent before and after 0Ω discharge, and the coefficient of variation of the dielectric loss tangent before and after 0Ω discharge are smaller than those in Comparative Examples 1 and 2. From this, it can be seen that the examples have good contact between the external electrode and the internal electrode, and good conductivity within the external electrode. This is presumed to be because, in the conductive material in a sol state, metal salts that precipitate silver and copper by heat treatment are dissolved, and the volume of the silver salt after metallic silver formation is made larger than the volume of the copper salt after metallic copper formation, so that copper diffuses sufficiently into the internal electrode during firing, while silver does not diffuse, and as shown in Figures 3 to 6, the silver particles 11 partially bond with the copper particles 12, becoming flattened bonded particles 13, which make it easier for the particles to contact each other. Furthermore, the presence of the flattened bonded particles 13 achieves good plating adhesion.

[0075] In contrast, in Comparative Example 1, the coefficient of variation of the dielectric loss tangent before and after 0Ω discharge, as well as the dielectric loss tangent after 0Ω discharge, are larger than those in the example. This is presumed to be because, in the conductive material for forming the external electrode, the volume of the silver salt after metallic silvering is smaller than the volume of the copper salt after metallic coppering, making it difficult for the flattened bonded particles formed by the bonding of silver and copper particles to grow, as shown in Figures 7 to 10, resulting in insufficient conductivity within the external electrode.

[0076] Furthermore, in Comparative Example 2, the dielectric loss tangent variation coefficient before 0Ω discharge and the dielectric loss tangent after 0Ω discharge showed larger values ​​than in the example. This is presumed to be because, as shown in Figures 11 and 12, the conductive material for forming the external electrode did not contain silver salt, resulting in insufficient conductivity within the external electrode.

[0077] Embodiments of this invention include the following:

[0078] <1> A ceramic body having multiple stacked ceramic layers and internal electrodes arranged along the interfaces between the ceramic layers, An external electrode provided on the surface of the ceramic body and electrically connected to the internal electrode, Equipped with, The external electrode comprises a conductive metal and a silicon-containing glass. The conductive metal contains silver and copper, with the silver component being more abundant than the copper component by volume, and the silver and copper exist in the forms of silver particles, copper particles, and bonded particles formed by the bonding of silver particles and copper particles. The bonding particles are flattened, Apart from the bonding surface between the silver particles and the copper particles in the bonded particles, copper is not present on the surface of the silver particles, and silver is not present on the surface of the copper particles. A portion of the copper contained in the external electrode is diffused into the internal electrode. Multilayer ceramic electronic components.

[0079] <2> The aforementioned internal electrode contains nickel as a conductive component. <1> Multilayer ceramic electronic components as described above.

[0080] <3> The multilayer ceramic electronic component in question is a multilayer ceramic capacitor. <1> or <2> Multilayer ceramic electronic components as described above.

[0081] <4> The material comprises a conductive metal salt that becomes a conductive metal as a conductive component when fired, a glass raw material that contains a metal salt for glass and becomes a silicon-containing glass when fired, and a solvent that dissolves or disperses the conductive metal salt and the glass raw material. The ratio of the content of the glass raw material to the content of the conductive metal salt is 0.04 or more and 1.40 or less, when converted to the mass of the conductive metal salt after metallization and the mass of the glass raw material after vitrification. The conductive metal salt includes a silver salt and a copper salt. The ratio of the volume of the silver salt after metallic silvering to the volume of the copper salt after metallic coppering is greater than 1. A conductive material in a sol state.

[0082] <5> The solvent has a boiling point of 145°C or lower. <4> The conductive material described above.

[0083] <6> The solvent comprises 2-methoxyethanol. <5> The conductive material described above.

[0084] <7> The silver salt comprises either silver carboxylate or silver nitrate, and the copper salt comprises either copper carboxylate or copper nitrate. <4> or <6> A conductive material as described in any of the following.

[0085] <8> Furthermore, including organic binders, <4> or <7> A conductive material as described in any of the following.

[0086] <9> The aforementioned organic binder contains hydroxypropyl cellulose, <8> The conductive material described above.

[0087] <10> A method for manufacturing a multilayer ceramic electronic component comprising a ceramic body having a plurality of stacked ceramic layers and internal electrodes arranged along the interfaces between the ceramic layers, and external electrodes provided on the surface of the ceramic body and electrically connected to the internal electrodes, So as to be in contact with the aforementioned internal electrode, <4> or <9> A step of applying a conductive material described in any of the above to the surface of the ceramic body, A step of heating and drying the coated conductive material at a temperature of 145°C or higher, Next, the conductive material is fired to form the external electrode, A method for manufacturing multilayer ceramic electronic components, comprising:

[0088] <11> The process further comprises forming a plating film on the external electrode. <10> A method for manufacturing multilayer ceramic electronic components as described above. [Explanation of Symbols]

[0089] 1. Multilayer ceramic capacitor 2. Ceramic body 3. Ceramic layer 4,5 Internal electrode 6,7 External electrode 8 Plating film 11 Silver particles 12 copper particles 13 Bonded particles

Claims

1. A ceramic body having multiple stacked ceramic layers and internal electrodes arranged along the interfaces between the ceramic layers, An external electrode is provided on the surface of the ceramic body and is electrically connected to the internal electrode, Equipped with, The external electrode comprises a conductive metal and a silicon-containing glass. The conductive metal contains silver and copper, with the silver component being more abundant than the copper component by volume, and the silver and copper exist in the forms of silver particles, copper particles, and bonded particles formed by the bonding of silver particles and copper particles. The bonding particles are flattened, Apart from the bonding surface between the silver particles and the copper particles in the bonded particles, copper is not present on the surface of the silver particles, and silver is not present on the surface of the copper particles. A portion of the copper contained in the external electrode is diffused into the internal electrode. Multilayer ceramic electronic components.

2. The multilayer ceramic electronic component according to claim 1, wherein the internal electrode contains nickel as a conductive component.

3. The multilayer ceramic electronic component is a multilayer ceramic capacitor, as described in claim 1.

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