Multilayer ceramic capacitor

Abstract

Provided is a multilayer ceramic capacitor provided with an internal electrode capable of maintaining a relatively high coverage rate even when the multilayer ceramic capacitor is thinned. A laminated ceramic capacitor (1) is provided with a laminated body (2) having: a plurality of laminated dielectric layers (3) containing a ceramic; and a plurality of internal electrodes (4, 5) disposed along each of a plurality of interfaces between the dielectric layers (3). When the conductive metal or the alloy containing the conductive metal is represented by X, the internal electrodes (4, 5) contain a conductive component and a ceramic component, the conductive component contains X, and the ceramic component contains XTiO3. Preferably, X is one selected from nickel, copper, silver and a silver-palladium alloy.

Description

Technical Field

[0001] The present invention relates to a multilayer ceramic capacitor, and more particularly to the composition of internal electrodes included in the multilayer ceramic capacitor. Background Art

[0002] Typically, a multilayer ceramic capacitor comprises a laminate having a plurality of dielectric layers formed of ceramic and a plurality of internal electrodes arranged along the interfaces between the dielectric layers; and a plurality of external electrodes provided on the outer surface of the laminate and electrically connected to the internal electrodes. The internal electrodes comprise a plurality of first internal electrodes and a plurality of second internal electrodes arranged alternately in the stacking direction of the laminate, and the external electrodes comprise a first external electrode electrically connected to the first internal electrodes and a second external electrode electrically connected to the second internal electrodes.

[0003] In order to achieve miniaturization and high capacitance of multilayer ceramic capacitors with this structure, it is required to thin the dielectric layer and internal electrodes and improve the coverage of the internal electrodes (electrode continuity). Generally speaking, during the firing process when manufacturing multilayer ceramic capacitors, the temperature at which the conductive metal particles contained in the conductive paste film that will become the internal electrodes is sintered is lower than the temperature at which the ceramic constituting the dielectric layer is sintered, so the metal particles contained in the internal electrodes are sintered first. This causes the coverage of the internal electrodes to decrease. In particular, for internal electrodes that are thinned to a thickness of less than 1.0 μm, there is a problem that the coverage is easily reduced, and this reduction in coverage easily hinders the achievement of high capacitance.

[0004] Therefore, in order to achieve high coverage and thinner internal electrodes, it is necessary to further increase the sintering temperature of the conductive metal particles contained in the conductive paste film that will become the internal electrodes during the firing process when manufacturing multilayer ceramic capacitors. This allows the sintering temperature of the metal particles contained in the conductive paste film that will become the internal electrodes to be closer to the temperature at which the ceramic constituting the dielectric layer begins sintering, aligning the shrinkage timing of the internal electrodes and the dielectric layer during sintering. As a result, the internal electrode coverage is increased, enabling higher capacitance.

[0005] According to the above-mentioned method, in order to improve the coverage of the internal electrodes and achieve higher capacitance, it is known to add a ceramic material having a composition similar to that of the ceramic constituting the dielectric layer, i.e., a common material, to the conductive paste used to form the internal electrodes, as described, for example, in paragraph 0004 of Patent Document 1 (Japanese Patent Application Laid-Open No. 2016-31807). The addition of the common material shifts the sintering timing of the metal particles contained in the conductive paste film, which will become the internal electrodes, to a higher temperature, allowing the sintering temperature of the metal particles contained in the conductive paste film to approach the sintering temperature of the ceramic constituting the dielectric layer.

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent Application Laid-Open No. 2016-31807 Summary of the Invention

[0009] Problems to be solved by the invention

[0010] However, even when common materials are added to the conductive paste used to form the internal electrodes, the sintering temperature of the metal particles contained in the conductive paste is still lower than that of the ceramic constituting the dielectric layer, and further improvements are desired. In particular, for internal electrodes that have been thinned to, for example, less than 1.0 μm, there is a strong demand for effective solutions to the reduced coverage that hinders increased capacitance.

[0011] Therefore, the present invention has been made in view of such problems, and an object of the present invention is to provide a multilayer ceramic capacitor including internal electrodes capable of maintaining a relatively high coverage even when the internal electrodes are thinned.

[0012] Technical solutions to solve problems

[0013] A multilayer ceramic capacitor according to the present invention includes a laminate having a plurality of laminated dielectric layers made of ceramic and a plurality of internal electrodes arranged along a plurality of interfaces between the dielectric layers.

[0014] In order to solve the above-mentioned technical problems, the present invention is characterized in that, when the conductive metal or the alloy containing the conductive metal is set as X, the internal electrode contains a conductive component and a ceramic component, the conductive component contains X, and the ceramic component contains XTiO3.

[0015] Effects of the Invention

[0016] According to the present invention, by including a ceramic component containing XTiO3 in the internal electrodes, which contains the same X as the conductive component X contained in the internal electrodes, the internal electrode coverage can be improved. Therefore, even if the internal electrodes are thinner, the internal electrode coverage is not reduced, and the increase in capacitance of the multilayer ceramic capacitor is not hindered. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 1 is a cross-sectional view schematically showing a multilayer ceramic capacitor 1 according to one embodiment of the present invention. DETAILED DESCRIPTION

[0018] Reference Figure 1 , the structure of a multilayer ceramic capacitor 1 according to one embodiment of the present invention will be described.

[0019] A multilayer ceramic capacitor 1 includes a laminate 2. The laminate 2 comprises a plurality of laminated dielectric layers 3 made of ceramic, and a plurality of internal electrodes 4 and 5 arranged along the interfaces between the plurality of dielectric layers 3. The internal electrodes 4 and 5 are divided into a plurality of first internal electrodes 4 and a plurality of second internal electrodes 5, which are arranged alternately in the stacking direction of the laminate 2. A first external electrode 6 and a second external electrode 7 are provided on the outer surfaces of the laminate 2, more specifically, on each of the opposing end surfaces. 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.

[0020] Dielectric layer 3 comprises, for example, a ceramic primarily composed of ABO3 (A is at least one of Ba, Ca, and Sr, and B is at least one of Ti and Zr). Alternatively, the ceramic may comprise ABO3 as a primary component and further comprise at least one of Mn, Mg, Si, Y, Dy, and Gd as a secondary component. In the experimental examples described below, dielectric layer 3 comprises a ceramic primarily composed of at least one selected from BaTiO3, SrTiO3, and CaZrO3.

[0021] Preferably, the internal electrodes 4 and 5 contain a conductive metal or an alloy containing the conductive metal as a conductive component, for example, one selected from nickel, copper, silver, and a silver-palladium alloy. Furthermore, as a characteristic composition, when the conductive metal or alloy containing the conductive metal as the conductive component is represented by X, the internal electrodes 4 and 5 contain a ceramic component containing XTiO3. The ceramic component containing XTiO3 preferably has an ilmenite crystal structure. As will be seen in the experimental examples described below, the internal electrodes 4 and 5 may further contain at least one selected from BaTiO3, SrTiO3, and CaZrO3, as a ceramic component, as contained in the dielectric layer 3.

[0022] The content of the ceramic component in the internal electrodes 4 and 5 is preferably selected to be 5% by mass or more and 15% by mass or less. The content is defined as {(mass of the ceramic component) / (mass of the ceramic component + mass of the conductive metal or alloy containing the conductive metal)} × 100 (the same applies hereinafter).

[0023] The external electrodes 6 and 7 are formed by applying a conductive paste containing Ag or Cu as a main conductive component to the end faces of the laminate 2 and then baking it. If necessary, the thick film formed by baking may be plated with Ni, for example, and then plated with Sn.

[0024] The multilayer ceramic capacitor 1 is manufactured, for example, through the following process. First, a ceramic slurry containing raw material powder of a ceramic having the composition described above is prepared. Next, an appropriate sheet forming method is applied to the ceramic slurry to form ceramic green sheets. Next, a conductive paste to be used as the internal electrodes 4 and 5 is applied to a given ceramic green sheet among the plurality of ceramic green sheets by printing or the like. Next, the plurality of ceramic green sheets are stacked and then press-bonded to obtain an unprocessed stack. Next, the unprocessed stack is fired. In this firing process, the ceramic green sheet becomes the dielectric layer 3. Then, external electrodes 6 and 7 are formed on the end faces of the stack 2.

[0025] The conductive paste to be used as the internal electrodes 4 and 5 when manufacturing the above-described multilayer ceramic capacitor 1 is preferably prepared as follows.

[0026] When making a conductive paste, the following steps are implemented: the first step is to prepare a ceramic powder slurry containing ceramic powder, an organic solvent and a dispersant; the second step is to prepare a metal powder slurry containing conductive metal powder, an organic solvent and a dispersant; the third step is to prepare an organic excipient containing an organic resin component and an organic solvent; and the fourth step is to mix the above-mentioned ceramic powder slurry, metal powder slurry and organic excipient.

[0027] More specifically, in the first step, ceramic powder and a dispersant are mixed in an organic solvent to prepare a ceramic powder slurry.

[0028] The ceramic powder can be varied depending on the type of conductive metal or alloy thereof constituting the conductive metal powder contained in the metal powder slurry produced in the second step described below. Specifically, assuming the conductive metal or alloy thereof constituting the conductive metal powder is X, the ceramic powder to be included in the ceramic powder slurry can be selected to contain a powder containing XTiO₃. The ceramic powder slurry may also contain, as needed, a powder containing at least one common material selected from, for example, BaTiO₃, SrTiO₃, and CaZrO₃ in addition to the aforementioned powders.

[0029] The ceramic powder containing XTiO₃ can suppress any potential reaction with the X-containing powder contained in the metal powder slurry produced in the second step during firing. The ceramic powder may contain XTiO₃ as a main component and at least one of Mn, Mg, Si, Y, Dy, and Gd as a secondary component. The inclusion of such secondary components can further suppress the growth of ceramic particles and, in some cases, effectively inhibit the sintering of metal particles.

[0030] As the dispersant to be mixed with the ceramic powder in the first step, for example, an anionic polymer dispersant can be used, and as the organic solvent, for example, dihydroterpineol can be used.

[0031] In the second step, a metal powder slurry is prepared by mixing a conductive metal powder and a dispersant in an organic solvent. For example, the conductive metal powder may be a powder containing one selected from nickel, copper, silver, and a silver-palladium alloy. The dispersant and organic solvent used in the second step can be the same as those used in the first step.

[0032] In the third step, an organic vehicle is prepared by mixing an organic resin component with an organic solvent. For example, ethyl cellulose resin can be used as the organic resin component. The organic solvent used in the third step can be the same as that used in the first step.

[0033] In the fourth step, the ceramic powder slurry, metal powder slurry, and organic vehicle are mixed. This produces a conductive paste that will become the internal electrodes 4 and 5. This conductive paste contains the ceramic powder slurry. As previously described, the ceramic powder slurry contains ceramic powder containing XTiO3. Therefore, after the firing step, the internal electrodes 4 and 5 of the multilayer ceramic capacitor 1 manufactured contain a ceramic component containing XTiO3.

[0034] The content of the ceramic powder in the conductive paste is preferably selected to be 5% by mass or more and 15% by mass or less.

[0035] Next, experimental examples conducted to determine the scope of the present invention and to confirm the effects of the present invention will be described.

[0036] [Experimental Example 1]

[0037] In Experimental Example 1, as shown in Table 1, the main component of the ceramic constituting the dielectric layer was set to BaTiO 3 , and the conductive component and ceramic component contained in the internal electrode were changed.

[0038] 1-1. Preparation of BaTiO3-based ceramic raw materials for dielectric layers

[0039] As starting materials, powders of BaCO₃ and TiO₂, the main components, were weighed and mixed in a ball mill for 72 hours, followed by heat treatment at a maximum temperature of 1000°C for 2 hours to obtain a heat-treated powder. Separately, powders of MnO, Dy₂O₃, MgO, SiO₂, and BaCO₃ were prepared as auxiliary components and weighed so that the auxiliary component powders had a composition ratio of 100%BaTiO₃ + 0.5%Mn + 1.0%Dy + 1.0%Mg + 1.0%Si + 2.0%Ba relative to the heat-treated powder. These auxiliary component powders were added to the heat-treated powder, mixed in a ball mill for 24 hours, and then dried to obtain a BaTiO₃-based ceramic raw material powder.

[0040] 1-2. Preparation of Conductive Paste for Internal Electrode Formation

[0041] As the conductive components contained in the internal electrodes, powders containing Ni, Cu, Ag, and an Ag-Pd alloy were prepared as shown in the "Conductive Components" section of "Internal Electrode" in Table 1. More specifically, a 0.7Ag-0.3Pd alloy was used as the Ag-Pd alloy.

[0042] On the other hand, as the ceramic component containing XTiO3 contained in the internal electrode, the ceramic powders containing NiTiO3, CuTiO3, AgTiO3, and (Ag, Pd)TiO3 shown in the "Ceramic Components" section of "Internal Electrode" in Table 1 were prepared. In addition, more specifically, (Ag, Pd)TiO3 was used as (Ag, Pd)TiO3. 0.7 Pd 0.3 )TiO3.

[0043] Furthermore, as another ceramic component contained in the internal electrode, as shown in the "Ceramic Component" column of "Internal Electrode" in Table 1, BaTiO3-based ceramic powder, which is a common material for ceramics constituting the dielectric layer, was also prepared.

[0044] These XTiO3-containing ceramic powders and BaTiO3-based ceramic powders were weighed to give the ratios expressed in volume % shown in the "Ceramic Components" section of Table 1. These powders, dihydroterpineol as an organic solvent, and an anionic polymer dispersant as a dispersant were premixed using a medium-free agitated mill, and then dispersed using a medium-agitated mill to prepare a ceramic powder slurry (first step).

[0045] Meanwhile, powders of Ni, Cu, Ag, and an Ag-Pd alloy listed in the "Conductive Component" section of "Internal Electrode" in Table 1, dihydroterpineol as an organic solvent, and an anionic polymer dispersant as a dispersant were dispersed using a three-roll mill to prepare a metal powder slurry (second step).

[0046] Furthermore, ethyl cellulose resin as an organic resin component and dihydroterpineol as an organic solvent were mixed to obtain an organic vehicle (third step).

[0047] Next, the metal powder slurry and the ceramic powder slurry were added to the organic vehicle, mixed, and dispersed to prepare a conductive paste for forming internal electrodes (fourth step).

[0048] Here, the content of the ceramic powder in the conductive paste for forming the internal electrode was set to 10% by mass.

[0049] 1-3. Fabrication of Multilayer Ceramic Capacitors

[0050] A ceramic slurry containing the BaTiO3-based ceramic raw material powder prepared in 1-1 above was prepared, and then a scraper method was applied to the ceramic slurry to form ceramic green sheets. Next, the conductive paste for forming internal electrodes prepared in 1-2 above was applied to a given ceramic green sheet among the plurality of ceramic green sheets by screen printing. Next, the plurality of ceramic green sheets were stacked and then press-bonded to obtain an unprocessed laminate. Next, the unprocessed laminate was fired. Then, external electrodes were formed on the end faces of the sintered laminate to produce a sample laminated ceramic capacitor.

[0051] 1-4. Evaluation

[0052] [Table 1]

[0053]

[0054] The internal electrodes and the dielectric layer located at the center in the height direction of the laminated body of the sample laminated ceramic capacitor were separated from each other by electric field peeling.

[0055] Next, the exposed internal electrode's center (the area halfway along the width and halfway along the length) was observed using a microscope at 100x magnification. The resulting image was analyzed to determine the ratio of the area occupied by the conductor film, which served as the internal electrode, in the exposed portion. This ratio was used as the "coverage" shown in Table 1. Samples with a "coverage" exceeding 80% were rated as good and marked with "○" in the "Evaluation" column. Samples with a "coverage" of 80% or less were rated as poor and marked with "×" in the "Evaluation" column.

[0056] 1-5. Investigation

[0057] In Samples 1-2, 4-5, 7-8, and 10-11 in Table 1, "Evaluation" is "○." In these Samples 1-2, 4-5, 7-8, and 10-11, the internal electrodes contain a conductive component and a ceramic component, the conductive component contains X, and the ceramic component contains XTiO3.

[0058] It is speculated that in samples 1-2, 4-5, 7-8, and 10-11, the XTiO3, which serves as a ceramic component in the internal electrode, contains X, which is the same as the conductive component in the internal electrode. Therefore, the conductive component contained in the internal electrode is not discharged from the internal electrode portion but remains, thereby playing a role in improving the heat resistance of the internal electrode and increasing the coverage to more than 83%.

[0059] Furthermore, as in Samples 2, 5, 8, and 11, the ratio of XTiO₃ in the ceramic component of the internal electrode does not necessarily have to be 100%. As long as it is 10% or more, an effect of improved coverage can be confirmed compared to the case where no XTiO₃ is contained. Furthermore, it is noted that the coverage of Samples 2 and 5, which have a 10% XTiO₃ ratio, is equivalent to the coverage of Samples 1 and 4, which have a 100% XTiO₃ ratio, respectively.

[0060] In contrast, samples 3, 6, 9, and 12, which were rated "×," did not contain XTiO as a ceramic component, but only BaTiO, a common ceramic material for the dielectric layer. As a result, the coverage dropped to 75% or less.

[0061] It is speculated that in Samples 3, 6, 9, and 12, BaTiO 3 is discharged from the internal electrode portion, the heat resistance of the internal electrode is not improved, and the coverage is reduced.

[0062] [Experimental Example 2]

[0063] In Experimental Example 2, as shown in Table 2, the main component of the ceramic constituting the dielectric layer was set to CaZrO 3 , and the conductive component and ceramic component contained in the internal electrode were changed.

[0064] 2-1. Preparation of CaZrO3-based ceramic raw materials for dielectric layers

[0065] As starting materials, powders of CaCO3 and ZrO2 as main components and powders of MnO, SiO2 and MgO as auxiliary components were weighed, mixed for 72 hours in a ball mill, and then heat treated at a maximum temperature of 1000°C for 2 hours to obtain CaZrO3-based ceramic raw material powder.

[0066] 2-2. Preparation of Conductive Paste for Internal Electrode Formation

[0067] As the conductive components contained in the internal electrodes, powders containing Ni, Cu, Ag, and an Ag-Pd alloy were prepared as described in "Conductive Components" under "Internal Electrode" in Table 2, similarly to Experimental Example 1. More specifically, a 0.7Ag-0.3Pd alloy was used as the Ag-Pd alloy.

[0068] On the other hand, as the ceramic component containing XTiO3 contained in the internal electrode, ceramic powders containing NiTiO3, CuTiO3, AgTiO3, and (Ag, Pd)TiO3 as shown in the "Ceramic Components" section of "Internal Electrode" in Table 2 were prepared. In addition, more specifically, (Ag, Pd)TiO3 was used as (Ag, Pd)TiO3. 0.7 Pd 0.3 )TiO3.

[0069] Furthermore, as another ceramic component contained in the internal electrode, as shown in the "Ceramic Component" column of "Internal Electrode" in Table 2, CaZrO3-based ceramic powder, which is a common material for ceramics constituting dielectric layers, was also prepared.

[0070] These XTiO3-containing ceramic powders and CaZrO3-based ceramic powders were weighed to give the ratios indicated by volume % in the "Ceramic Components" section of Table 1. These powders, dihydroterpineol as an organic solvent, and an anionic polymer dispersant as a dispersant were premixed using a medium-free agitated mill, and then dispersed using a medium-agitated mill to prepare a ceramic powder slurry (Step 1).

[0071] Meanwhile, powders of Ni, Cu, Ag, and an Ag-Pd alloy listed in the "Conductive Component" section of "Internal Electrode" in Table 2, dihydroterpineol as an organic solvent, and an anionic polymer dispersant as a dispersant were dispersed using a three-roll mill to prepare a metal powder slurry (second step).

[0072] Furthermore, ethyl cellulose resin as an organic resin component and dihydroterpineol as an organic solvent were mixed to obtain an organic vehicle (third step).

[0073] Next, the metal powder slurry and the ceramic powder slurry were added to the organic vehicle, mixed, and dispersed to prepare a conductive paste for forming internal electrodes (fourth step).

[0074] Here, the content of the ceramic powder in the conductive paste for forming the internal electrode was set to 10% by mass.

[0075] 2-3. Fabrication of Multilayer Ceramic Capacitors

[0076] A ceramic slurry containing the CaZrO3-based ceramic raw material powder prepared in 2-1 above was prepared. Next, the ceramic slurry was subjected to a doctor blade method to form ceramic green sheets. Subsequently, the same steps as in Experimental Example 1 were followed to produce a sample multilayer ceramic capacitor.

[0077] 2-4. Evaluation

[0078] [Table 2]

[0079]

[0080] According to the same procedure as in Experimental Example 1, the “coverage ratio” was determined as shown in Table 2, and the evaluation was performed in the same manner.

[0081] 2-5. Investigation

[0082] In Samples 21-22, 24-25, 27-28, and 30-31 in Table 2, the "Evaluation" is "○." In these Samples 21-22, 24-25, 27-28, and 30-31, the internal electrodes contain a conductive component and a ceramic component, the conductive component contains X, and the ceramic component contains XTiO3.

[0083] It is speculated that in samples 21-22, 24-25, 27-28, and 30-31, the XTiO3 serving as the ceramic component in the internal electrode contains X, which is the same as the conductive component in the internal electrode. Therefore, the conductive component contained in the internal electrode is not discharged from the internal electrode portion but remains, thereby playing a role in improving the heat resistance of the internal electrode and increasing the coverage to more than 83%.

[0084] In addition, as in samples 22, 25, 28 and 31, the ratio of XTiO3 in the ceramic component of the internal electrode does not necessarily have to be 100%. As long as it is 10% or more, the effect of improving the coverage can be confirmed compared with the case where XTiO3 is not included.

[0085] In contrast, samples 23, 26, 29, and 32, which were rated "X," did not contain XTiO3 as a ceramic component, but only CaZrO3-based ceramic, a common material for ceramics constituting the dielectric layer. As a result, the coverage was as low as 72%.

[0086] It is speculated that in Samples 23, 26, 29, and 32, CaZrO 3 is discharged from the internal electrode portion, the heat resistance of the internal electrode is not improved, and the coverage is reduced.

[0087] [Experimental Example 3]

[0088] In Experimental Example 3, as shown in Table 3, the main component of the ceramic constituting the dielectric layer was set to SrTiO 3 , and the conductive component and ceramic component contained in the internal electrode were changed.

[0089] 3-1. Preparation of SrTiO3-based ceramic raw materials constituting the dielectric layer

[0090] As starting materials, powders of SrCO3 and TiO2 as main components and powders of MnO, SiO2 and MgO as auxiliary components were weighed, mixed for 72 hours in a ball mill, and then heat treated at a maximum temperature of 1000°C for 2 hours to obtain SrTiO3-based ceramic raw material powder.

[0091] 3-2. Preparation of Conductive Paste for Internal Electrode Formation

[0092] As the conductive components contained in the internal electrodes, powders containing Ni, Cu, Ag, and an Ag-Pd alloy were prepared as described in "Conductive Components" under "Internal Electrode" in Table 3, similarly to Experimental Example 1. More specifically, a 0.7Ag-0.3Pd alloy was used as the Ag-Pd alloy.

[0093] On the other hand, as the ceramic component containing XTiO3 contained in the internal electrode, the ceramic powders containing NiTiO3, CuTiO3, AgTiO3, and (Ag, Pd)TiO3 shown in the "Ceramic Components" section of "Internal Electrode" in Table 3 were prepared. In addition, more specifically, (Ag, Pd)TiO3 was used as (Ag, Pd)TiO3. 0.7 Pd 0.3 )TiO3.

[0094] Furthermore, as another ceramic component contained in the internal electrode, as shown in the "Ceramic Component" column of "Internal Electrode" in Table 3, SrTiO3-based ceramic powder, which is a common material for ceramics constituting dielectric layers, was also prepared.

[0095] These XTiO3-containing ceramic powders and SrTiO3-based ceramic powders were weighed so as to have the ratios expressed in volume % shown in the "Ceramic Components" section of Table 3. These powders, dihydroterpineol as an organic solvent, and an anionic polymer dispersant as a dispersant were premixed using a medium-free agitated mill, and then dispersed using a medium-agitated mill to prepare a ceramic powder slurry (first step).

[0096] Meanwhile, powders of Ni, Cu, Ag, and an Ag-Pd alloy listed in the "Conductive Component" section of "Internal Electrode" in Table 3, dihydroterpineol as an organic solvent, and an anionic polymer dispersant as a dispersant were dispersed using a three-roll mill to prepare a metal powder slurry (second step).

[0097] Furthermore, ethyl cellulose resin as an organic resin component and dihydroterpineol as an organic solvent were mixed to obtain an organic vehicle (third step).

[0098] Next, the metal powder slurry and the ceramic powder slurry were added to the organic vehicle, mixed, and dispersed to prepare a conductive paste for forming internal electrodes (fourth step).

[0099] Here, the content of the ceramic powder in the conductive paste for forming the internal electrode was set to 10% by mass.

[0100] 3-3. Fabrication of Multilayer Ceramic Capacitors

[0101] A ceramic slurry containing the SrTiO3-based ceramic raw material powder prepared in 3-1 above was prepared. Next, the ceramic slurry was subjected to a doctor blade method to form ceramic green sheets. Subsequently, the same steps as in Experimental Example 1 were followed to produce a sample multilayer ceramic capacitor.

[0102] 3-4. Evaluation

[0103] [Table 3]

[0104]

[0105] According to the same procedure as in Experimental Example 1, the “coverage ratio” was determined as shown in Table 3, and the evaluation was performed in the same manner.

[0106] 3-5. Investigation

[0107] In Samples 41-42, 44-45, 47-48, and 50-51 in Table 3, the "Evaluation" is "○." In these Samples 41-42, 44-45, 47-48, and 50-51, the internal electrodes contain a conductive component and a ceramic component, the conductive component contains X, and the ceramic component contains XTiO3.

[0108] It is speculated that in samples 41-42, 44-45, 47-48, and 50-51, the XTiO3 serving as the ceramic component in the internal electrode contains X, which is the same as the conductive component in the internal electrode. Therefore, the conductive component contained in the internal electrode is not discharged from the internal electrode portion but remains, thereby playing a role in improving the heat resistance of the internal electrode and increasing the coverage to more than 82%.

[0109] In addition, as in samples 42, 45, 48 and 51, the ratio of XTiO3 in the ceramic component of the internal electrode does not necessarily have to be 100%. As long as it is 10% or more, the effect of improving the coverage can be confirmed compared with the case where XTiO3 is not included.

[0110] In contrast, samples 43, 46, 49, and 52, which were rated "X," did not contain XTiO3 as a ceramic component, but only BaTiO3-based ceramics, a common material for ceramics constituting the dielectric layer. As a result, the coverage was as low as 70%.

[0111] It is speculated that in Samples 43, 46, 49, and 52, SrTiO 3 is discharged from the internal electrode portion, the heat resistance of the internal electrode is not improved, and the coverage is reduced.

[0112] In the experimental examples described above, nickel, copper, silver, and a silver-palladium alloy were selected as the conductive component contained in the internal electrodes. However, other conductive metals or alloys thereof may also be selected.

[0113] Among the embodiments of the present invention, there are the following embodiments.

[0114] <1>

[0115] A laminated ceramic capacitor, wherein:

[0116] A laminated body is provided,

[0117] The laminated body has:

[0118] a plurality of stacked dielectric layers comprising ceramic; and

[0119] A plurality of internal electrodes are respectively arranged along a plurality of interfaces between the dielectric layers.

[0120] When the conductive metal or the alloy containing the conductive metal is represented by X, the internal electrode includes a conductive component and a ceramic component, the conductive component includes X, and the ceramic component includes XTiO 3 .

[0121] <2>

[0122] according to <1> The multilayer ceramic capacitor, wherein

[0123] The ceramic component containing the XTiO 3 has an ilmenite crystal structure.

[0124] <3>

[0125] according to <1> or <2> The multilayer ceramic capacitor, wherein

[0126] The internal electrode has a thickness of less than 1.0 μm.

[0127] <4>

[0128] according to <1> to <3> The multilayer ceramic capacitor according to any one of claims , wherein

[0129] The inner electrodes have a coverage rate exceeding 80%.

[0130] <5>

[0131] according to <1> to <4> The multilayer ceramic capacitor according to any one of claims , wherein

[0132] The X is one selected from nickel, copper, silver, and silver-palladium alloy.

[0133] <6>

[0134] A conductive paste for forming internal electrodes of a multilayer ceramic capacitor, comprising conductive metal powder, ceramic powder, an organic solvent, and an organic binder, wherein:

[0135] When the conductive metal or the alloy containing the conductive metal is represented by X, the conductive paste contains a conductive component and a ceramic component, the conductive component contains X, and the ceramic component contains XTiO 3 .

[0136] Description of Reference Numerals

[0137] 1: Multilayer ceramic capacitor;

[0138] 2: laminate;

[0139] 3: dielectric layer;

[0140] 4, 5: internal electrodes;

[0141] 6, 7: External electrodes.

Claims

1. A laminated ceramic capacitor, wherein: A laminated body is provided, The laminated body has: a plurality of stacked dielectric layers comprising ceramic; and A plurality of internal electrodes are respectively arranged along a plurality of interfaces between the dielectric layers. When the conductive metal or the alloy containing the conductive metal is represented by X, the internal electrode includes a conductive component and a ceramic component, the conductive component includes X, and the ceramic component includes XTiO 3 .

2. The multilayer ceramic capacitor according to claim 1, wherein The ceramic component containing the XTiO 3 has an ilmenite crystal structure.

3. The multilayer ceramic capacitor according to claim 1 or 2, wherein The internal electrode has a thickness of less than 1.0 μm.

4. The multilayer ceramic capacitor according to any one of claims 1 to 3, wherein The inner electrodes have a coverage rate exceeding 80%.

5. The multilayer ceramic capacitor according to any one of claims 1 to 4, wherein The X is one selected from nickel, copper, silver, and silver-palladium alloy.

6. A conductive paste for forming internal electrodes of a multilayer ceramic capacitor, comprising conductive metal powder, ceramic powder, an organic solvent, and an organic binder, wherein: When the conductive metal or the alloy containing the conductive metal is represented by X, the conductive paste contains a conductive component and a ceramic component, the conductive component contains X, and the ceramic component contains XTiO 3 .

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