Multilayer ceramic capacitor

Abstract

A multilayer ceramic capacitor (1) is provided with: a body part (10) including a plurality of dielectric ceramic layers (20) and a plurality of internal electrode layers (30) laminated in a thickness direction (T); and external electrodes (11, 12) which are provided on the surface of the main body part (10) and which are electrically connected to the internal electrode layer (30). The dielectric ceramic layer (20) contains crystal particles (40) comprising a perovskite-type composite oxide. The perovskite-type composite oxide may include barium (Ba), titanium (Ti), and a rare earth element (Re), and may also include calcium (Ca) and / or zirconium (Zr). When GI (Re) is the atomic concentration ratio of Re / Ti in the intra-grain region (GI) of the crystal particles (40) and GB (Re) is the atomic concentration ratio of Re / Ti in the grain boundary region (GB) of the crystal particles (40), the crystal particles (40) satisfy the following formulae (1-1): 0.074 > = GI (Re) > = 0.005 and (1-2): 1.10 > = GB (Re) / GI (Re) > = 0.90. When the atomic concentration ratio of Ca / Ti in the intra-grain region (GI) of the crystal particles (40) is GI (Ca) and the atomic concentration ratio of Ca / Ti in the grain boundary region (GB) of the crystal particles (40) is GB (Ca), the following formulae are satisfied: 2-1: 0.250 > = GI (Ca) > = 0, and 2-2: 1.10 > = GB (Ca) / GI (Ca) > = 0.90 (excluding the case of GI (Ca) = 0). When the atomic concentration ratio of the total of Ba and Ca to the total of Ti and Zr is (Ba + Ca) / (Ti + Zr), formula 3: 0.997 lt is satisfied; (Ba + Ca) / (Ti + Zr) lt; and 1.030.

Description

Technical Field

[0001] This invention relates to multilayer ceramic capacitors. Background Technology

[0002] Patent document 1 discloses a stacked ceramic capacitor in which a dielectric layer and an internal electrode layer are alternately stacked, consisting of barium titanate crystal particles with a calcium concentration of less than 0.2 atomic% and barium calcium titanate crystal particles with a calcium concentration of more than 0.4 atomic%. In the multilayer ceramic capacitor described in Patent Document 1, the barium titanate crystal particles and the barium calcium titanate crystal particles contain magnesium, two rare earth elements in combination of one of yttrium and holmium and one of terbium and dysprosium, and vanadium. Furthermore, the ratio of the content of magnesium and the rare earth element of yttrium and holmium in the central part of the barium titanate crystal particles to the content of magnesium and the rare earth element of yttrium and holmium on the surface side of the barium titanate crystal particles is greater than the ratio of the content of magnesium and the rare earth element of yttrium and holmium in the central part of the barium calcium titanate crystal particles to the content of magnesium and the rare earth element of yttrium and holmium on the surface side of the barium calcium titanate crystal particles.

[0003] Prior art literature

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2008-135638 Summary of the Invention

[0006] The problem the invention aims to solve

[0007] According to Patent Document 1, barium titanate crystal particles become highly cubic particles in the core-shell structure. By allowing such highly cubic barium titanate crystal particles to coexist among barium calcium titanate crystal particles, it is possible to obtain a multilayer ceramic capacitor with high insulation resistance even after formal firing and minimal reduction in insulation resistance over time during high-temperature load testing, as well as a dielectric ceramic composed of barium titanate crystal particles and barium calcium titanate crystal particles.

[0008] However, in multilayer ceramic capacitors, as described in Patent Document 1, where the dielectric layer (hereinafter also referred to as the dielectric ceramic layer) is composed of crystalline particles with a core-shell structure, localized electric field concentration can occur when a high electric field strength is applied. This can lead to a decrease in insulation resistance over time during high-temperature load tests. Therefore, from the perspective of obtaining multilayer ceramic capacitors with long high-temperature load life and high electrical reliability, there is still room for improvement.

[0009] This invention was made to solve the above-mentioned problems, and its purpose is to provide a multilayer ceramic capacitor with long service life under high temperature load and high electrical reliability.

[0010] Technical solutions for solving the problem

[0011] The multilayer ceramic capacitor of the present invention comprises: a body portion including a plurality of dielectric ceramic layers and a plurality of internal electrode layers stacked in the thickness direction; and an external electrode disposed on the surface of the body portion and electrically connected to the internal electrode layers. The dielectric ceramic layers comprise crystalline particles composed of perovskite-type composite oxides. The perovskite-type composite oxides comprise barium (Ba), titanium (Ti), and rare earth elements (Re), and may also comprise at least one of calcium (Ca) and zirconium (Zr). When the atomic concentration ratio of Re / Ti in the intragranular region of the crystalline particles is set as GI(Re), and the atomic concentration ratio of Re / Ti in the grain boundary region of the crystalline particles is set as GB(Re), Equation 1-1: 0.074 ≥ GI(Re) ≥ 0.005, and Equation 1-2: 1.10 ≥ GB(Re) / GI(Re) ≥ 0.90. When the atomic concentration ratio of Ca / Ti in the intragranular region of the above-mentioned crystalline particles is set as GI(Ca), and the atomic concentration ratio of Ca / Ti in the grain boundary region of the above-mentioned crystalline particles is set as GB(Ca), Equation 2-1 is satisfied: 0.250≥GI(Ca)≥0, and Equation 2-2: 1.10≥GB(Ca) / GI(Ca)≥0.90 (except for the case where GI(Ca)=0). When the atomic concentration ratio of the total of Ba and Ca relative to the total of Ti and Zr is set as (Ba+Ca) / (Ti+Zr), Equation 3 is satisfied: 0.997<(Ba+Ca) / (Ti+Zr)<1.030.

[0012] Invention Effects

[0013] According to the present invention, a multilayer ceramic capacitor with long service life under high temperature load and high electrical reliability can be provided. Attached Figure Description

[0014] Figure 1 This is a perspective view schematically illustrating an example of a multilayer ceramic capacitor of the present invention.

[0015] Figure 2 It is along Figure 1 The image shows an example of an LT cross-sectional view of the II-II line of a multilayer ceramic capacitor, including the length direction L and the thickness direction T.

[0016] Figure 3 It is along Figure 1 The diagram shows an example of a cross-sectional view of the III-III line of a multilayer ceramic capacitor, including the width direction W and the thickness direction T.

[0017] Figure 4 A is an example of an enlarged cross-sectional view of the dielectric ceramic layer 20 sandwiched between the inner electrode layer 30. Figure 4 B is the component that constitutes Figure 4 A schematic diagram of an example of crystalline particles of the dielectric ceramic layer 20 in the region enclosed by dashed lines in A.

[0018] Figure 5 A is the bright-field image of the transmission electron microscope in sample 1-1. Figure 5 B is a mapping image showing the distribution of the Dy element in sample 1-1. Detailed Implementation

[0019] The laminated ceramic capacitor of the present invention will now be described. Furthermore, the present invention is not limited to the embodiments described below, and can be appropriately modified without changing the spirit of the invention. Moreover, structures obtained by combining two or more of the preferred structures described in the following embodiments are also part of the present invention.

[0020] In this specification, terms indicating the relationship between elements (such as "perpendicular", "parallel", "orthogonal", etc.) and terms indicating the shape of elements are not merely expressions with a strict meaning, but expressions that imply substantially equal ranges, for example, also include differences of a few percent.

[0021] The accompanying drawings are schematic diagrams, and their dimensions, aspect ratios, and scales may sometimes differ from the actual product. In the drawings, the same reference numerals are used for identical or equivalent parts. Furthermore, in each drawing, the same reference numerals are used for the same elements, and redundant descriptions are omitted.

[0022] Figure 1 This is a perspective view schematically illustrating an example of a multilayer ceramic capacitor of the present invention.

[0023] Figure 1 The stacked ceramic capacitor 1 shown includes a body portion 10 and external electrodes 11 and 12 disposed on the surface of the body portion 10. In the body portion 10, the length direction, width direction, and thickness direction are respectively defined by double arrows L, W, and T.

[0024] The body portion 10 is, for example, cuboid in shape. In this case, the body portion 10 has a first main surface 10a and a second main surface 10b that are opposite each other in the thickness direction T, a first side surface 10c and a second side surface 10d that are opposite each other in the width direction W that is orthogonal to the thickness direction T, and a first end surface 10e and a second end surface 10f that are opposite each other in the length direction L that is orthogonal to the thickness direction T and the width direction W.

[0025] At least one of the corners and edges of the body portion 10 may also have rounded corners. Here, the corner is the part where three faces of the body portion 10 intersect, and the edge is the part where two faces of the body portion 10 intersect.

[0026] An external electrode 11 is provided on the first end face 10e of the body portion 10. The external electrode 11 may also be wrapped around a portion of the first main face 10a, the second main face 10b, the first side face 10c, and the second side face 10d of the body portion 10.

[0027] An external electrode 12 is disposed on the second end face 10f of the body portion 10. The external electrode 12 may also extend around a portion of the first main face 10a, the second main face 10b, the first side face 10c, and the second side face 10d of the body portion 10.

[0028] The dimensions of the multilayer ceramic capacitor 1 are not particularly limited. For example, the length L dimension is 0.4 mm or more and 5.7 mm or less, the width W dimension is 0.2 mm or more and 5.0 mm or less, and the thickness T dimension is 0.125 mm or more and 5.0 mm or less.

[0029] Figure 2 It is along Figure 1 The image shows an example of an LT cross-sectional view of the II-II line of a multilayer ceramic capacitor, including the length direction L and the thickness direction T. Figure 3 It is along Figure 1 The image shows an example of a cross-sectional view of the III-III line of a multilayer ceramic capacitor, including the width direction W and the thickness direction T.

[0030] The body portion 10 includes a plurality of dielectric ceramic layers 20 and a plurality of internal electrode layers 30 stacked in the thickness direction T.

[0031] The internal electrode layer 30 includes a first internal electrode layer 31 and a second internal electrode layer 32 that are alternately arranged in the thickness direction T.

[0032] The first internal electrode layer 31 extends to the first end face 10e of the body portion 10, where it is electrically connected to the external electrode 11.

[0033] The second internal electrode layer 32 extends to the second end face 10f of the body portion 10, where it is electrically connected to the external electrode 12.

[0034] The first internal electrode layer 31 and the second internal electrode layer 32, sandwiched between the dielectric ceramic layer 20, are not electrically connected. Therefore, if a voltage is applied between the first internal electrode layer 31 and the second internal electrode layer 32 via the external electrodes 11 and 12, charge is accumulated. The accumulated charge generates an electrostatic capacitance, thereby functioning as a capacitor element.

[0035] Outside the plurality of dielectric ceramic layers 20 and the plurality of internal electrode layers 30 stacked in the thickness direction T, an outer layer portion 25 consisting only of stacked dielectric ceramic layers 20 may also be provided. The outer layer portion 25 is located on both main surfaces of the body portion 10 and is a dielectric ceramic layer located between each main surface and the internal electrode layer 30 closest to that main surface. On the other hand, the area that can be sandwiched between the outer layer portions 25 on both sides is also called an inner layer portion.

[0036] Figure 4 A is an example of an enlarged cross-sectional view of the dielectric ceramic layer 20 sandwiched between the inner electrode layer 30. Figure 4 B is the component that constitutes Figure 4 A schematic diagram of an example of crystalline particles of the dielectric ceramic layer 20 in the region enclosed by dashed lines in A.

[0037] The dielectric ceramic layer 20 is made of ceramic. Specifically, the dielectric ceramic layer 20 contains crystalline particles 40 composed of perovskite-type composite oxides (see reference). Figure 4 A and Figure 4 B) is used as the main component. Hereinafter, the crystalline particles 40 composed of the perovskite-type composite oxide described above will also be referred to as the main crystalline particles. The main crystalline particles contain barium titanate (BaTiO3) based compounds. Therefore, the dielectric ceramic layer 20 can also be described as a sintered body containing BaTiO3 based compounds. BaTiO3 is a ferroelectric material that exhibits a tetragonal crystal structure at room temperature and has a high dielectric constant. Therefore, by setting the BaTiO3 based compound as the main component, the dielectric constant of the dielectric ceramic layer 20 can be increased, thereby enabling the capacitor to have a larger capacitance.

[0038] In this specification, the term "main component" refers to the component with the highest mass percentage in the ceramic. There is no particular limitation on the mass percentage of the main component as long as it is less than 100% by mass; for example, it can be 50% or more by mass, 60% or more by mass, 70% or more by mass, 80% or more by mass, or 90% or more by mass.

[0039] BaTiO3 compounds are not particularly limited as long as they are perovskite-type composite oxides mainly containing Ba and Ti. For example, BaTiO3 compounds can also be compounds in which a portion of Ba and / or Ti in BaTiO3 is replaced with other elements. For example, a portion of Ba can be replaced with alkaline earth metals such as strontium (Sr) and calcium (Ca), and a portion of Ti can be replaced with transition metals such as zirconium (Zr) and hafnium (Hf). Furthermore, the molar ratio (hereinafter referred to as the A / B ratio) of the A-site elements (Ba, Sr, Ca, etc.) and B-site elements (Ti, Zr, Hf, etc.) in BaTiO3 compounds is not strictly limited to 1:1. As long as the perovskite-type crystal structure is maintained, deviations in the molar ratio of the A-site elements and B-site elements are permissible.

[0040] The perovskite-type composite oxide constituting crystalline particle 40 includes barium (Ba), titanium (Ti), and rare earth elements (Re). Rare earth elements (Re) are the collective term for elements in the periodic table that constitute the group consisting of scandium (Sc) with atomic number 21, yttrium (Y) with atomic number 39, and lanthanum (La) with atomic number 57 to lutetium (Lu) with atomic number 71. The perovskite-type composite oxide constituting crystalline particle 40 may also contain one rare earth element (Re), or it may contain a combination of multiple rare earth elements (Re). Furthermore, rare earth elements (Re) may be contained only in the BaTiO3-based compound as the main crystalline particle, or they may be contained in the main crystalline particle and grain boundaries or triple-grain boundaries. When rare earth elements (Re) are contained in the main crystalline particle, they may occupy Ba sites (A sites), Ti sites (B sites), or both sites in the BaTiO3-based compound.

[0041] By incorporating rare earth elements (Re) into the dielectric ceramic layer 20, the reliability and temperature characteristics of the dielectric constant of the multilayer ceramic capacitor 1 can be improved. The BaTiO3-based compound, which is the main component of the dielectric ceramic layer 20, sometimes contains many oxygen vacancies generated during the sintering process. These oxygen vacancies tend to reduce the insulation resistance when accompanied by electron compensation, and furthermore, their movement under an electric field easily leads to a time-dependent decrease in insulation resistance. Therefore, if rare earth elements (Re) are included in the dielectric ceramic layer 20, the rare earth elements (Re) tend to dissolve in the Ba or Ti sites of the BaTiO3-based compound. The dissolved rare earth elements (Re) act as donors or acceptors, hindering the movement of oxygen vacancies or inhibiting the generation of conduction electrons. Therefore, the degradation of insulation resistance is reduced, and the high-temperature load life is improved. Furthermore, the dielectric constant of the BaTiO3-based compound exhibits a large temperature dependence near its Curie temperature Tc. Therefore, by dissolving rare earth elements (Re) in BaTiO3 compounds, it is possible to make the temperature change of the dielectric constant flatter over a wide range, including the Curie temperature Tc.

[0042] The types of rare earth elements (Re) are not particularly limited, but preferably include at least one selected from the group consisting of yttrium (Y), lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), and lutetium (Lu), more preferably including at least dysprosium (Dy). Dy is an element located near the middle of the lanthanides in the periodic table, and its ionic radius is also of moderate size. Therefore, the ability to solidify at both the Ba site (A site) and Ti site (B site) of BaTiO3 compounds is effective in improving reliability. The dielectric ceramic layer 20 may contain only Dy as a rare earth element (Re), or it may contain other rare earth elements (Re) together with Dy.

[0043] The perovskite-type composite oxide constituting the crystalline particles 40 may also contain at least one of calcium (Ca) and zirconium (Zr). In this case, these elements may be contained in any of the main crystalline particles, grain boundaries, and triple grain boundaries.

[0044] When the atomic concentration ratio of Re / Ti in the intragranular region GI of the crystalline particle 40 is set to GI(Re), and the atomic concentration ratio of Re / Ti in the grain boundary region GB of the crystalline particle 40 is set to GB(Re), the following conditions are met:

[0045] Equation 1-1: 0.074 ≥ GI (Re) ≥ 0.005, and

[0046] Formula 1-2: 1.10≥GB(Re) / GI(Re)≥0.90.

[0047] When defining the region enclosed by the grain boundary of crystalline particle 40 as a grain, firstly, as Figure 4 As shown in B, the region formed by the boundary surfaces of three or more adjacent grains is defined as a triplet grain boundary region (TJ). A triplet grain boundary region (TJ) is not a triplet grain boundary itself, but rather signifies the region containing a triplet grain boundary.

[0048] Next, as Figure 4 As shown in Figure B, a grain boundary region GB is defined as a region centered on the same plane as the boundary between two adjacent grains, that does not contain the triplet grain boundary region TJ, and has a width of 10 nm. The grain boundary region GB is not the grain boundary itself, but rather signifies the region that contains the grain boundary.

[0049] Moreover, such as Figure 4 As shown in B, the region within the grain that does not contain the grain boundary region GB and the triple grain boundary region TJ is defined as the grain interior region GI.

[0050] By uniformly dissolving rare earth elements (Re) throughout the entire dielectric ceramic layer 20, the above-mentioned equations 1-1 and 1-2 can be satisfied. When the dielectric ceramic layer 20 contains two or more rare earth elements (Re), the total concentration of rare earth elements (Re) only needs to satisfy equations 1-1 and 1-2.

[0051] If Equation 1-1 is not satisfied and GI(Re) > 0.074, segregation of rare earth elements (Re) occurs, thus significantly reducing electrical reliability. On the other hand, if GI(Re) < 0.005, it becomes difficult to obtain the effect of improving electrical reliability brought about by rare earth elements (Re).

[0052] If equations 1-2 are not satisfied, and GB(Re) / GI(Re) > 1.10 or GB(Re) / GI(Re) < 0.90, then the concentration difference of rare earth elements (Re) increases in the intragranular region GI and the grain boundary region GB, resulting in electric field concentration and thus reduced electrical reliability.

[0053] When the atomic concentration ratio of Re / Ti in the triangular grain boundary region TJ of the crystallized particle 40 is set as TJ(Re), for example, at least one of Equation 1-3: 1.10≥TJ(Re) / GI(Re)≥0.90 and Equation 1-4: 1.10≥TJ(Re) / GB(Re)≥0.90 can be satisfied.

[0054] When the atomic concentration ratio of Ca / Ti in the intragranular region GI of the crystalline particle 40 is set to GI(Ca), and the atomic concentration ratio of Ca / Ti in the grain boundary region GB of the crystalline particle 40 is set to GB(Ca), the following conditions are met:

[0055] Equation 2-1: 0.250 ≥ GI (Ca) ≥ 0, and

[0056] Equation 2-2: 1.10≥GB(Ca) / GI(Ca)≥0.90 (wherein, except for the case where GI(Ca)=0).

[0057] When GI(Ca) = 0, only equation 2-1 needs to be satisfied.

[0058] When GI(Ca)>0, Ca is uniformly dissolved throughout the dielectric ceramic layer 20, thereby satisfying Equations 2-1 and 2-2 above.

[0059] On the other hand, when GI(Ca)=0, GB(Ca)=0 is preferred.

[0060] If Equation 2-1 is not satisfied and GI(Ca) > 0.250, a secondary phase will be generated in the dielectric ceramic layer 20, thus significantly reducing electrical reliability.

[0061] If equation 2-2 is not satisfied, and GB(Ca) / GI(Ca) > 1.10 or GB(Ca) / GI(Ca) < 0.90, then the Ca concentration difference increases in the intragranular region GI and the grain boundary region GB, resulting in electric field concentration and thus reduced electrical reliability.

[0062] When the atomic concentration ratio of Ca / Ti in the triangular grain boundary region TJ of the crystallized particles 40 is set to TJ(Ca), for example, at least one of Equation 2-3: 1.10≥TJ(Ca) / GI(Ca)≥0.90 (except for the case where GI(Ca)=0) and Equation 2-4: 1.10≥TJ(Ca) / GB(Ca)≥0.90 (except for the case where GB(Ca)=0) can be satisfied. In the case where GI(Ca)=0, it is preferable that GB(Ca)=TJ(Ca)=0.

[0063] When the atomic concentration ratio of the total of Ba and Ca relative to the total of Ti and Zr is set as (Ba+Ca) / (Ti+Zr), the following condition is met:

[0064] Formula 3: 0.997<(Ba+Ca) / (Ti+Zr)<1.030.

[0065] As mentioned above, the dielectric ceramic layer 20 may or may not contain Ca, and may or may not contain Zr.

[0066] If Equation 3 is not satisfied and (Ba+Ca) / (Ti+Zr)≤0.997, an anisotropic phase is generated in the dielectric ceramic layer 20, thereby reducing electrical reliability. Furthermore, the insulation resistance also decreases. On the other hand, if (Ba+Ca) / (Ti+Zr)≥1.030, the crystallinity decreases, thereby reducing electrostatic capacitance.

[0067] Based on the above, by satisfying Equations 1-1, 1-2, 2-1, 2-2 and 3, a multilayer ceramic capacitor 1 with long high-temperature load life and high electrical reliability can be obtained.

[0068] Equation 1-1 preferably satisfies 0.074 ≥ GI (Re) ≥ 0.05. Under this condition, electrical reliability can be further improved.

[0069] Equation 2-1 preferably satisfies 0.06 ≥ GI (Ca) ≥ 0.03. Under this condition, electrical reliability can be further improved.

[0070] In addition, the various atomic concentration ratios in each region can be determined by analyzing the cross-section of the dielectric ceramic layer 20 using a transmission electron microscope (TEM)-energy dispersive X-ray spectroscopy (EDX) device and performing image analysis on the obtained cross-sectional EDX image.

[0071] Specifically, the central portion of the multilayer ceramic capacitor 1 is ground to obtain an LT profile, thereby exposing the dielectric ceramic layer 20. The main crystal particles near the central portion of the exposed dielectric ceramic layer 20 are observed using TEM, and an EDX image showing the atomic distribution within the crystal particles 40 is obtained. Preferably, 100 crystal particles 40 are observed.

[0072] The perovskite-type composite oxide constituting the crystalline particles 40 may also further comprise at least one metallic element (M) selected from the group consisting of vanadium (V), molybdenum (Mo), niobium (Nb), and tantalum (Ta). In this case, these elements may be contained in any of the main crystalline particles, grain boundaries, and triplet grain boundaries. The metallic element (M) preferably comprises at least vanadium (V).

[0073] When the perovskite-type composite oxide constituting the crystalline particle 40 contains a metal element (M), and when the atomic concentration ratio of M / Ti in the intragranular region GI of the crystalline particle 40 is set to GI(M) and the atomic concentration ratio of M / Ti in the grain boundary region GB of the crystalline particle 40 is set to GB(M), it is preferable to satisfy the following:

[0074] Equation 4-1: 0.050 ≥ GI (M) ≥ 0.001.

[0075] By dissolving a metallic element (M) in the dielectric ceramic layer 20, the above equation 4-1 can be satisfied. When the dielectric ceramic layer 20 contains two or more types of M, the total concentration of M only needs to satisfy equation 4-1.

[0076] If Equation 4-1 is not satisfied and GI(M) > 0.050, the insulation resistance becomes easier to reduce significantly. On the other hand, if GI(M) < 0.001, it becomes difficult to obtain the effect of improving electrical reliability brought about by M.

[0077] Equation 4-1 preferably satisfies 0.005 ≥ GI(M) ≥ 0.003. Under this condition, electrical reliability can be further improved.

[0078] The perovskite-type composite oxide constituting the crystalline particles 40 may also contain elements other than barium (Ba), titanium (Ti), rare earth elements (Re), calcium (Ca), zirconium (Zr), and metallic elements (M). Examples of such other elements include manganese (Mn), magnesium (Mg), silicon (Si), and aluminum (Al). These elements may be present in any of the main crystalline particles, grain boundaries, and triple grain boundaries.

[0079] The average thickness of the dielectric ceramic layer 20 is not particularly limited. For example, it can be 0.3 μm or more and 5 μm or less, 0.4 μm or more and 4 μm or less, 0.5 μm or more and 3 μm or less, 0.6 μm or more and 2 μm or less, or 0.7 μm or more and 1 μm or less. If the average thickness of the dielectric ceramic layer 20 is within the above range, degradation of the insulation properties can be prevented. Furthermore, if the average thickness of the dielectric ceramic layer 20 is within the above range, the dielectric ceramic layer 20 is thinned, which can improve the electrostatic capacitance. In addition, the number of dielectric ceramic layers 20 is, for example, 50 or more and 1000 or less.

[0080] The average grain size of the ceramic grains contained in the dielectric ceramic layer 20 is not particularly limited, but is preferably 100 nm or more and 400 nm or less, and more preferably 150 nm or more and 300 nm or less.

[0081] The internal electrode layer 30 contains a conductive metal. Examples of conductive metals include nickel (Ni), copper (Cu), silver (Ag), palladium (Pd), and alloys thereof. The internal electrode layer 30 may also contain other components besides a conductive metal. Examples of other components include ceramic components that function as a common material. Examples of ceramic components include BaTiO3-based compounds contained in the dielectric ceramic layer 20.

[0082] The average thickness of the internal electrode layer 30 is not particularly limited, but is, for example, 0.3 μm or more and 0.7 μm or less. If the average thickness of the internal electrode layer 30 is within the above range, defects such as electrode interruption can be suppressed. Furthermore, if the average thickness of the internal electrode layer 30 is within the above range, the reduction in the proportion of the electrically functional dielectric ceramic layer 20 in the capacitor can be suppressed, thereby suppressing the reduction of electrostatic capacitance.

[0083] In addition, the WT cross-section of the body portion 10 exposed by grinding was observed using a scanning electron microscope (SEM). The thicknesses of five lines were measured, including the center line along the thickness direction T passing through the center of the WT cross-section and two lines drawn at equal intervals on both sides from the center line. The average thickness of the dielectric ceramic layer 20 and the internal electrode layer 30 was set as the average of the five measured values.

[0084] Furthermore, the average grain size of the ceramic grains contained in the dielectric ceramic layer 20 can be determined by analyzing cross-sectional images scanned using SEM. For example, the average grain size of the ceramic grains can be determined using software for determining the average grain size in accordance with the JIS G 0551:2013 standard.

[0085] The structure of external electrodes 11 and 12 is not particularly limited. For example, external electrodes 11 and 12 may also have a laminated structure including a base layer, a first plating layer, and a second plating layer from the end face side of the laminated ceramic capacitor 1. The base layer may include metals such as nickel (Ni) and copper (Cu). In addition, the base layer may also include ceramic powder as a common material in addition to metal. The first plating layer may be a nickel (Ni) plating layer, for example. The second plating layer may be a tin (Sn) plating layer, for example. A conductive resin layer may also be provided between the base layer and the first plating layer. The conductive resin layer is a layer containing conductive metal particles such as copper (Cu), silver (Ag), and nickel (Ni) and resin. The shape of external electrodes 11 and 12 is not limited as long as they are components that are electrically connected to the internal electrode layer 30 and function as external input / output terminals.

[0086] The manufacturing method of the multilayer ceramic capacitor of the present invention is not limited as long as the above requirements are met.

[0087] For example, the manufacturing method of the multilayer ceramic capacitor of the present invention includes: a step of preparing a green sheet containing at least barium (Ba), titanium (Ti), and rare earth elements (Re) (green sheet preparation step); a step of applying a conductive paste to the surface of the green sheet to obtain a green sheet with an internal electrode pattern (electrode pattern forming step); a step of stacking and pressing multiple green sheets to obtain a multilayer block (stacking step); a step of cutting the obtained multilayer block to obtain a multilayer chip (cutting step); a step of performing a debinding treatment and a firing treatment on the obtained multilayer chip to obtain a body portion (firing step); and a step of forming an external electrode on the obtained body portion (external electrode forming step). Details of each step are described below.

[0088] <Raw Film Production Process>

[0089] In the green sheet fabrication process, green sheets containing at least barium (Ba), titanium (Ti), and rare earth elements (Re) are produced. The green sheet is a precursor to the dielectric ceramic layer, containing the main component raw materials and additives for the dielectric ceramic layer. There are no particular limitations on the method for fabricating the green sheet. For example, additives are mixed with the main component raw materials to produce the dielectric raw material; binders and solvents are added and mixed to the obtained dielectric raw material to form a slurry; and the resulting slurry is then used to form the green sheet.

[0090] As the main raw material, powdered BaTiO3 compounds can be used. For BaTiO3 compounds, known ceramic raw materials such as oxides, carbonates, hydroxides, nitrates, organic acid salts, alkoxides, and / or chelates can be used for synthesis using known ceramic synthesis methods such as solid-state reaction, hydrothermal synthesis, and alkoxide methods.

[0091] In the synthesis of BaTiO3 compounds, for example, in addition to Ba, Ti, and Re raw materials, Ca raw materials are also wet-stirred using a ball mill as needed, and the dried powder is heated to 1300°C. Furthermore, in order to facilitate the solid dissolution of Re and Ca, it is preferable to perform the wet grinding and heating process three times after heating.

[0092] As a raw material for Ba, well-known ceramic raw materials such as Ba oxides, carbonates, and acetates can be used.

[0093] As a Ti raw material, known ceramic raw materials such as Ti oxides, carbonates, acetates, and chlorides can be used.

[0094] As a Re raw material, known ceramic raw materials such as Re oxides, carbonates, and acetates can be used.

[0095] As a raw material for Ca, known ceramic raw materials such as Ca oxides and carbonates can be used.

[0096] The added raw materials can also include other additives such as Mn, Mg, Si, Al, and V. Furthermore, in order to adjust the composition of the BaTiO3-based compounds that are the main components, barium carbonate (BaCO3), titanium dioxide (TiO2), and other Ba and Ti raw materials can also be added to the added raw materials.

[0097] The slurry preparation can be carried out using known methods, such as mixing an organic binder and an organic solvent with the dielectric material. For example, known binders such as polyvinyl butyral adhesives can be used as organic binders. Furthermore, known solvents such as toluene and ethanol can be used as organic solvents. Additives such as plasticizers can also be added to the slurry as needed. Furthermore, the forming of the green sheet can also be carried out using known methods such as the doctor blade method or the rip in-line process.

[0098] <Electrode Pattern Forming Process>

[0099] In the electrode patterning process, a conductive paste is applied to the surface of a green sheet to obtain a green sheet with an internal electrode pattern. This internal electrode pattern becomes the internal electrode layer after firing. Conductive metals included in the conductive paste can be, for example, nickel (Ni), copper (Cu), silver (Ag), palladium (Pd), and alloys containing them. Furthermore, ceramic components that function as common materials can also be added to the conductive paste. For example, the main component raw material of a dielectric ceramic layer can be used as a ceramic component. The conductive paste can be applied using known methods such as screen printing or gravure printing.

[0100] <Lamination Process>

[0101] In the lamination process, multiple green sheets are stacked and pressed together to obtain a laminated block. Green sheets with internal electrode patterns are used, but some green sheets without internal electrode patterns can also be used. The stacking and pressing are performed using known methods.

[0102] <Cutting process>

[0103] In the cutting process, the obtained laminated block is cut to obtain laminated pieces. Cutting is performed to obtain pieces of a given size, and at least a portion of the internal electrode pattern is exposed on the end face of the laminated piece.

[0104] <Firing Process>

[0105] In the firing process, the obtained laminated sheets are subjected to a debinding treatment and a firing treatment to obtain the body. Through the firing treatment, the green sheet and the internal electrode pattern are co-fired, forming the dielectric ceramic layer and the internal electrode layer, respectively. The conditions for the debinding treatment are determined based on the type of organic binder contained in the green sheet and the internal electrode pattern. Furthermore, the firing treatment is carried out at a temperature that sufficiently densifies the laminated sheets. For example, it can be carried out at a temperature of 1200°C or higher and 1300°C or lower for 1 hour or more and 10 hours or less. The firing treatment is carried out in an atmosphere where the BaTiO3-based compounds, as the main component, are not reduced, and the oxidation of the conductive metal is suppressed. For example, an atmosphere with an oxygen partial pressure of 1.9 × 10⁻⁶. -11 MPa or higher and 6.4 × 10 -9 The firing process can be carried out using an N2-H2-H2O gas flow rate below MPa. Furthermore, annealing can be performed after firing.

[0106] The sintering of the stacked wafers is carried out, for example, at a heating rate of 400°C / min. By accelerating the heating rate during sintering, grain growth can be suppressed. Furthermore, by including a large amount of glass components such as Si and Al as additives, Re can be directed towards the grain boundary region GB (see reference). Figure 4 B) Dissolve and excrete.

[0107] <External Electrode Formation Process>

[0108] In the external electrode forming process, external electrodes are formed on the obtained body portion. The formation of external electrodes can be performed using known methods. For example, a conductive paste containing metals such as silver (Ag), copper (Cu), and / or nickel (Ni) can be applied and fired onto the end face of the body portion where the internal electrode layer is exposed. Alternatively, it can be formed by applying conductive paste to both end faces of the laminated wafers before firing. Furthermore, the formed electrode can be used as a substrate layer, and a plating film of nickel (Ni), tin (Sn), etc., can be formed on it. Based on the above, a multilayer ceramic capacitor is manufactured.

[0109] The following information is disclosed in this specification.

[0110] <1> A multilayer ceramic capacitor, comprising:

[0111] The body comprises multiple dielectric ceramic layers and multiple internal electrode layers stacked in the thickness direction; and

[0112] External electrodes are disposed on the surface of the aforementioned body portion and are electrically connected to the aforementioned internal electrode layer.

[0113] The aforementioned dielectric ceramic layer contains crystalline particles composed of perovskite-type composite oxides.

[0114] The aforementioned perovskite-type composite oxides contain barium (Ba), titanium (Ti), and rare earth elements (Re), and may also contain at least one of calcium (Ca) and zirconium (Zr).

[0115] When the atomic concentration ratio of Re / Ti in the intragranular region of the above-mentioned crystalline particles is set as GI(Re) and the atomic concentration ratio of Re / Ti in the grain boundary region of the above-mentioned crystalline particles is set as GB(Re), the following conditions are met:

[0116] Equation 1-1: 0.074 ≥ GI (Re) ≥ 0.005, and

[0117] Formula 1-2: 1.10≥GB(Re) / GI(Re)≥0.90,

[0118] When the atomic concentration ratio of Ca / Ti in the intragranular region of the above-mentioned crystalline particles is set as GI(Ca) and the atomic concentration ratio of Ca / Ti in the grain boundary region of the above-mentioned crystalline particles is set as GB(Ca), the following conditions are met:

[0119] Equation 2-1: 0.250 ≥ GI (Ca) ≥ 0, and

[0120] Equation 2-2: 1.10≥GB(Ca) / GI(Ca)≥0.90 (wherein, except for the case where GI(Ca)=0).

[0121] When the atomic concentration ratio of the total of Ba and Ca relative to the total of Ti and Zr is set as (Ba+Ca) / (Ti+Zr), the following condition is met.

[0122] Formula 3: 0.997<(Ba+Ca) / (Ti+Zr)<1.030.

[0123] <2> according to <1> The described multilayer ceramic capacitors, among which,

[0124] Equation 1-1 above satisfies 0.074≥GI(Re)≥0.05.

[0125] <3> according to <1> or <2> The described multilayer ceramic capacitors, among which,

[0126] Equation 2-1 above satisfies 0.06≥GI(Ca)≥0.03.

[0127] <4> according to <1> to <3> Among the multilayer ceramic capacitors described in any one of the following,

[0128] The aforementioned perovskite-type composite oxide also contains at least one metallic element (M) selected from the group consisting of vanadium (V), molybdenum (Mo), niobium (Nb) and tantalum (Ta).

[0129] <5> according to <4> The described multilayer ceramic capacitors, among which,

[0130] When the atomic concentration ratio of M / Ti in the intragranular region of the above-mentioned crystalline particles is set as GI(M) and the atomic concentration ratio of M / Ti in the grain boundary region of the above-mentioned crystalline particles is set as GB(M), the following conditions are met:

[0131] Equation 4-1: 0.050 ≥ GI (M) ≥ 0.001.

[0132] <6> according to <5> The described multilayer ceramic capacitors, among which,

[0133] Equation 4-1 above satisfies 0.005≥GI(M)≥0.003.

[0134] <7> according to <4> to <6> Among the multilayer ceramic capacitors described in any one of the following,

[0135] The aforementioned metallic element (M) contains at least vanadium (V).

[0136] <8> according to <1> to <7> Among the multilayer ceramic capacitors described in any one of the following,

[0137] The aforementioned rare earth elements (Re) include at least one selected from the group consisting of yttrium (Y), lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), and lutetium (Lu).

[0138] <9> according to <8> The described multilayer ceramic capacitors, among which,

[0139] The rare earth elements (Re) mentioned above include at least dysprosium (Dy).

[0140] Example

[0141] The following provides more specific embodiments of the multilayer ceramic capacitor of the present invention. However, the present invention is not limited to these embodiments.

[0142] [Example 1]

[0143] In Example 1, the effect of the content of rare earth elements (Re) was confirmed. In this example, vanadium (V) was used as an example of a metallic element (M).

[0144] (1) Fabrication of multilayer ceramic capacitors

[0145] A sample of a multilayer ceramic capacitor was fabricated using the process shown below.

[0146] First, raw material powders such as BaCO3 powder, TiO2 powder, and rare earth oxide powder (e.g., Dy2O3 powder) were wet-stirred using a ball mill, and the dried powder was heated at 1300°C. The operation of wet-crushing again after heating and heating at 1300°C was carried out 3 times to obtain dielectric powder.

[0147] A polyvinyl butyral-based binder and a plasticizer were added to the obtained dielectric powder, and toluene and ethanol were added, and it was made into a slurry using a wet mill, and the slurry was formed to obtain a green sheet. The thickness of the obtained green sheet after sintering densification was 1.7 μm.

[0148] On the surface of the obtained green sheet, a conductive paste mainly composed of nickel was screen-printed to form a pattern of a conductive paste layer that becomes an internal electrode layer.

[0149] After that, 201 green sheets with a conductive paste layer formed on the surface were stacked such that the sides where the conductive paste layer was led out were different from each other, and green sheets without a conductive paste layer were provided on the top and bottom, and on this basis, the whole was crimped to fabricate a stacked block.

[0150] The obtained stacked block was cut to obtain green stacked chips. Cutting was performed such that the size of the fabricated multilayer ceramic capacitor became 3.2 mm × 1.6 mm.

[0151] The obtained green stacked chips were heat-treated at 280°C in a N2 gas stream to burn off the binder. Next, firing was carried out for 2 hours under the conditions of 1260°C in a N2-H2-H2O gas stream and an oxygen partial pressure of 1.6×10 -9 MPa.

[0152] In the fired stacked chips, on the end face where the internal electrode layer was led out, a conductive paste mainly composed of Cu was applied and baked at 800°C to form an external electrode, and a Ni plating layer and a Sn plating layer were formed on the surface of the external electrode.

[0153] Through this, the multilayer ceramic capacitor of Example 1 was fabricated. The obtained multilayer ceramic capacitor had an outer shape of length 3.2 mm × width 1.6 mm × thickness 1.6 mm. In addition, the number of dielectric ceramic layers sandwiched by the internal electrode layer was 200 layers, and the thickness of each dielectric ceramic layer was 1.7 μm.

[0154] (2) Evaluation

[0155] For the multilayer ceramic capacitor obtained in Example 1, various characteristics were evaluated as follows. <F

[0156] <TEM Observation / EDX Analysis>

[0157] The dielectric ceramic layer of the multilayer ceramic capacitor was observed using electric field radiation transmission electron microscopy (FE-TEM), and the composition of fine regions was analyzed using an energy-dispersive X-ray spectroscopy (EDX) device attached to the TEM. The specimens were prepared by thin-film fabrication of the dielectric ceramic layer using the FIB lift-out method. Observation and analysis were performed under the following conditions.

[0158] - Device: JEM-2200FS / Noran System 7, manufactured by Nippon Electronics Co., Ltd.

[0159] - Field of view: n=2

[0160] - Multiplier: 60,000x

[0161] - Pixel size: 9.2nm / pixel

[0162] - Spot diameter: 1nmφ

[0163] - Measurement: EDX cumulative count 100 times

[0164] Figure 5 A is the bright-field image of the transmission electron microscope in sample 1-1. Figure 5 B is a mapping image showing the distribution of the Dy element in sample 1-1.

[0165] For each sample, GI(Re), GB(Re), GI(Ca), and GB(Ca) were determined, and the ratios of GB(Re) / GI(Re) and GB(Ca) / GI(Ca) were calculated. The results are shown in Table 1.

[0166] Furthermore, rare earth elements (Re) occupy A and B sites in perovskite structures represented as ABO3, excluding the oxygen (O) sites, but the quantitative ratio of each site is not necessarily clear. However, it is a fact that rare earth elements (Re) replace A and B sites at a certain ratio and are dissolved, forming a perovskite structure in this state. The A / B ratio shown in Table 1 indicates that only Ba, Ca, Ti, and Zr were extracted from the perovskite structure containing dissolved rare earth elements (Re) in the (Ba+Ca) / (Ti+Zr) ratio.

[0167] <Reliability (MTTF)>

[0168] For multilayer ceramic capacitors, high-accelerated life tests (HALT) were conducted to obtain the mean time to failure (MTTF). In the high-accelerated life tests, the time to failure was measured under two measurement conditions. Specifically, high-temperature loads were applied to the specimens under the conditions of a temperature of 175°C and a test voltage of 50 V, and a temperature of 160°C and a test voltage of 50 V. Moreover, the time when the insulation resistance became 200 kΩ or less was determined as the time to failure. The time to failure was measured for 72 specimens fabricated under the same conditions.

[0169] Next, the obtained data was plotted on Weibull probability paper to obtain the Weibull distribution. In the obtained Weibull distribution, linear regression was performed on the relationship between the time to failure and the cumulative failure rate, and the slope was obtained as the shape parameter m. In addition, the time to failure at which the cumulative failure rate became 63.2% was read, and using this time to failure and the shape parameter m corresponding to the slope of the regression line, the mean time to failure (MTTF) at a test voltage of 50 V was determined. Samples with an MTTF of 200 hours or more under any of the two temperature conditions in the high-accelerated life tests were judged as qualified products. The results are shown in Table 1.

[0170] <XRD analysis>

[0171] Regarding the presence or absence of a heterogeneous phase in the multilayer ceramic capacitor, XRD (powder X-ray diffraction) was used for evaluation. The multilayer ceramic capacitor was crushed in a mortar to remove the electrode portion, thereby preparing an evaluation specimen. The heterogeneous phase (secondary component layer) described in the examples is a crystal phase defined as Dy2Ti2O7, and if this crystal phase exists, the MTTF in the dielectric significantly decreases.

[0172] <Measurement conditions>

[0173] Apparatus: D8 Advance manufactured by Bruker AXS

[0174] Tube target: Cu (sealed X-ray tube)

[0175] Optical system: Concentrating optical system

[0176] <Dielectric constant>

[0177] The electrostatic capacitance of each specimen was measured, and the dielectric constant was calculated. Using an automatic bridge measuring instrument, an AC voltage of 1 Vrms and 1 kHz was applied at a temperature of 25°C for measurement. The dielectric constant εr was calculated based on the obtained electrostatic capacitance value, the opposing area of the internal electrode layer, and the thickness of the dielectric ceramic layer.

[0178] <Resistivity>

[0179] The insulation resistance of each sample was measured, and the resistivity was calculated. Specifically, an insulation resistance meter was used to measure the insulation resistance by applying a 10V DC voltage for 120 seconds at a temperature of 25°C. Furthermore, the resistivity was calculated based on the obtained insulation resistance value, the opposing area of ​​the internal electrode layers, and the thickness of the dielectric ceramic layer.

[0180] [Table 1]

[0181]

[0182] In Table 1, the samples marked with an asterisk (*) are comparative examples outside the scope of this invention. The same applies to the following tables.

[0183] According to Table 1, it can be confirmed that multilayer ceramic capacitors with long MTTF and high electrical reliability can be obtained by satisfying Equation 1-1: 0.074 ≥ GI(Re) ≥ 0.005 and Equation 1-2: 1.10 ≥ GB(Re) / GI(Re) ≥ 0.90. In particular, it can be confirmed that the electrical reliability is further improved when Equation 1-1 satisfies 0.074 ≥ GI(Re) ≥ 0.05.

[0184] [Example 2]

[0185] In Example 2, the effect of calcium (Ca) content was confirmed.

[0186] Except for varying the amount of CaCO3 powder added during the preparation of the dielectric powder, multilayer ceramic capacitors were fabricated using the same method as in Example 1, and various characteristics were evaluated. The results are shown in Table 2.

[0187] [Table 2]

[0188]

[0189] According to Table 2, it can be confirmed that multilayer ceramic capacitors with long MTTF and high electrical reliability can be obtained by satisfying Equation 2-1: 0.250 ≥ GI(Ca) ≥ 0 and Equation 2-2: 1.10 ≥ GB(Ca) / GI(Ca) ≥ 0.90 (except for the case where GI(Ca) = 0). In particular, it can be confirmed that the electrical reliability is further improved when Equation 2-1 satisfies 0.06 ≥ GI(Ca) ≥ 0.03.

[0190] [Example 3]

[0191] In Example 3, the effect of the content of the metal element (M) was confirmed.

[0192] In addition to varying the amount of V2O5 powder added when producing the dielectric powder, multilayer ceramic capacitors were produced by the same method as in Example 1, and various characteristics were evaluated. The results are shown in Table 3.

[0193] <WD-XRF Analysis>

[0194] Regarding the amount of Ti used to calculate the atomic concentration ratio of V / Ti, compositional analysis was performed by WD-XRF (wavelength-dispersive X-ray fluorescence spectrometry). The multilayer ceramic capacitor was pulverized in a mortar so that the total weight became 0.1 g, thereby producing an evaluation sample. The measurement conditions are described below.

[0195] <Measurement Conditions>

[0196] Pretreatment: Glass fusion (glass beads) method

[0197] Measurement diameter: 30 nm φ

[0198] <ICP-AES Analysis>

[0199] Regarding the amount of V used to calculate the atomic concentration ratio of V / Ti, compositional analysis was performed by ICP-AES (inductively coupled plasma optical emission spectrometry). The multilayer ceramic capacitor was pulverized in a mortar and acid-dissolved, thereby producing an evaluation sample. The measurement conditions are described below.

[0200] <Measurement Conditions>

[0201] Apparatus: iCAP6300 (manufactured by Thermo Fisher Scientific)

[0202] Measurement wavelength range: 166 - 847 nm

[0203] Analysis method: Acid dissolution method

[0204] [Table 3]

[0205]

[0206] From Table 3, it can be confirmed that by satisfying Equation 4-1: 0.050 ≥ GI(M) ≥ 0.001, a multilayer ceramic capacitor can be obtained that not only has a long MTTF, high electrical reliability, but also has a high insulation resistance and excellent insulation characteristics. In particular, it can be confirmed that when Equation 4-1 satisfies 0.005 ≥ GI(M) ≥ 0.003, the electrical reliability is further improved.

[0207] Explanation of Reference Numerals

[0208] 1: Multilayer ceramic capacitor

[0209] 10: Body part

[0210] 10a: 1st main side

[0211] 10b: 2nd main side

[0212] 10c: First side

[0213] 10d: Second side view

[0214] 10e: First end face

[0215] 10f: Second end face

[0216] 11, 12: External electrodes

[0217] 20: Dielectric ceramic layer

[0218] 25: Outer layer

[0219] 30: Internal electrode layer

[0220] 31: First internal electrode layer

[0221] 32: Second inner electrode layer

[0222] 40: Crystallized particles

[0223] GB: Grain Boundary Region

[0224] GI: Intragranular region

[0225] TJ: Triangular grain boundary region

[0226] L: Length direction

[0227] T: Thickness direction

[0228] W: Width direction.

Claims

1. A multilayer ceramic capacitor, comprising: The body comprises multiple dielectric ceramic layers and multiple internal electrode layers stacked in the thickness direction; and External electrodes are disposed on the surface of the body portion and are electrically connected to the internal electrode layer. The dielectric ceramic layer comprises crystalline particles composed of perovskite-type composite oxides. The perovskite-type composite oxide contains barium (Ba), titanium (Ti), and rare earth element Re, and may also contain at least one of calcium (Ca) and zirconium (Zr). When the atomic concentration ratio of Re / Ti in the intragranular region of the crystalline particles is set to GI(Re) and the atomic concentration ratio of Re / Ti in the grain boundary region of the crystalline particles is set to GB(Re), the following conditions are met: Equation 1-1: 0.074 ≥ GI (Re) ≥ 0.005, and Formula 1-2: 1.10≥GB(Re) / GI(Re)≥0.90, When the atomic concentration ratio of Ca / Ti in the intragranular region of the crystalline particles is set to GI (Ca) and the atomic concentration ratio of Ca / Ti in the grain boundary region of the crystalline particles is set to GB (Ca), the following conditions are met: Equation 2-1: 0.250 ≥ GI (Ca) ≥ 0, and Equation 2-2: 1.10 ≥ GB (Ca) / GI (Ca) ≥ 0.90, where, Except for the case where GI(Ca) = 0, When the atomic concentration ratio of the total of Ba and Ca relative to the total of Ti and Zr is set as (Ba+Ca) / (Ti+Zr), the following condition is met. Formula 3: 0.997<(Ba+Ca) / (Ti+Zr)<1.

030.

2. The multilayer ceramic capacitor according to claim 1, wherein, Equation 1-1 satisfies 0.074≥GI(Re)≥0.

05.

3. The multilayer ceramic capacitor according to claim 1 or 2, wherein, Equation 2-1 satisfies 0.06≥GI(Ca)≥0.

03.

4. The multilayer ceramic capacitor according to any one of claims 1 to 3, wherein, The perovskite-type composite oxide also contains at least one metallic element M selected from the group consisting of vanadium (V), molybdenum (Mo), niobium (Nb), and tantalum (Ta).

5. The multilayer ceramic capacitor according to claim 4, wherein, When the atomic concentration ratio of M / Ti in the intragranular region of the crystalline particles is set as GI(M) and the atomic concentration ratio of M / Ti in the grain boundary region of the crystalline particles is set as GB(M), the following conditions are met: Equation 4-1: 0.050 ≥ GI (M) ≥ 0.

001.

6. The multilayer ceramic capacitor according to claim 5, wherein, Equation 4-1 satisfies 0.005≥GI(M)≥0.

003.

7. The multilayer ceramic capacitor according to any one of claims 4 to 6, wherein, The metallic element M contains at least vanadium (V).

8. The multilayer ceramic capacitor according to any one of claims 1 to 7, wherein, The rare earth element Re comprises at least one selected from the group consisting of yttrium (Y), lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), and lutetium (Lu).

9. The multilayer ceramic capacitor according to claim 8, wherein, The rare earth element Re contains at least dysprosium (Dy).

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