Dielectric compositions and multilayer ceramic electronic components

Abstract

To provide a dielectric composition less likely to cause pulse pressure-resistant failure than before, and a multilayer ceramic electronic component containing the dielectric composition.SOLUTION: A dielectric composition comprises a dielectric particle containing a main component (1.020<m) expressed by a composition formula [(CaxSr(1-x))O]m[(TiyHfzZr(1-y-z))O2], a grain boundary phase located between the dielectric particles, and a segregated phase containing at least Ca, Si, and O (oxygen). Among the segregated phases, a segregated phase that further contains Mn is defined as a first segregated phase, and a segregated phase that does not substantially contain Mn is defined as a second segregated phase. Further, the number of the first segregated phases included in a predetermined cross-sectional area of the dielectric composition is N1, and the number of the second segregated phases is N2, the dielectric composition satisfies 0.23<(N1 / (N1+N2))≤1.00.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] This disclosure relates to a dielectric composition and a multilayer ceramic electronic component containing the dielectric composition. [Background technology]

[0002] Electronic circuits and power supply circuits incorporated into electronic devices often contain numerous electronic components, such as multilayer ceramic capacitors, that utilize the dielectric properties exhibited by dielectric materials. As dielectric materials used in such electronic components, (Ca,Sr)(Zr,Ti,Hf)O3-based dielectric compositions, as shown in Patent Document 1, are known.

[0003] The dielectric composition disclosed in Patent Document 1 exhibits small capacitance changes with temperature and possesses C0G characteristics as defined by the EIA (Electronic Industries Alliance Standard). Therefore, this dielectric composition is suitably used in multilayer ceramic electronic components for temperature compensation. However, it has become clear that in multilayer ceramic electronic components containing this dielectric composition, reducing the interlayer thickness of the dielectric layer increases the likelihood of pulse breakdown voltage failure. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Patent No. 4678022 [Overview of the project] [Problems that the invention aims to solve]

[0005] This disclosure is made in view of the above circumstances, and its purpose is to provide a dielectric composition that is less prone to pulse breakdown voltage failure than conventional materials, and a multilayer ceramic electronic component containing the dielectric composition. [Means for solving the problem]

[0006] To achieve the above object, the dielectric composition according to the present disclosure is a main component represented by the composition formula [(Ca

[0010] , Si , ,

[0007] ,

[0009] , , Si , , , , , Mn , Mn , , , , ,

[0008] Sr (1-x) )O] m [(Ti y Hf z Zr (1-y-z) )O2], dielectric particles, a grain boundary phase located between the dielectric particles, and a segregation phase containing at least Ca, Si, and O (oxygen), and the composition formula satisfies 1.020 < m, Among the segregation phases, the segregation phase further containing Mn is defined as the first segregation phase, and the segregation phase substantially free of Mn is defined as the second segregation phase. Let the number of the first segregation phases included in a predetermined cross-sectional area of the dielectric composition be N1, and the number of the second segregation phases be N2. Then, 0.23 < (N1 / (N1 + N2)) ≤ 1.00 is satisfied.

[0007] <00001 seventy-one>As a result of intensive studies, the inventors of the present disclosure have found that by having the above characteristics, the dielectric composition can reduce the defective rate of the pulse withstand voltage compared to the prior art.

[0008] Let the content rate of Mn in the first segregation phase be M Mn (mol%) in terms of MnO, and the content rate of Si in the first segregation phase be M Si (mol%) in terms of SiO2, Preferably, the first segregation phase satisfies 0.38 < (M Mn / M Si ) ≤ 1.30.

[0009] Preferably, the Mn concentration in the grain boundary phase is higher than the Mn concentration inside the dielectric particles, and the dielectric particles have a concentration gradient in which the Mn concentration decreases from the grain boundary toward the center of the particle, and substantially no Al concentration gradient.

[0010] The multilayer ceramic electronic component according to this disclosure comprises a ceramic layer containing the above-mentioned dielectric composition and an internal electrode layer in contact with the ceramic layer. The Mn content in the aforementioned ceramic layer is C D (Assuming mol%), the Mn content in the internal electrode layer is C IE (as mole%), (C IE / C D ) < 1.51 is satisfied.

[0011] Because the multilayer ceramic electronic component possesses the above-mentioned characteristics, the failure rate of pulse withstand voltage can be reduced compared to conventional components. Furthermore, the multilayer ceramic electronic component has COG characteristics and can be suitably used as an electronic component for temperature compensation. [Brief explanation of the drawing]

[0012] [Figure 1] Figure 1 is a schematic diagram showing a cross-section of a multilayer ceramic capacitor according to one embodiment of the present disclosure. [Figure 2] Figure 2 is an enlarged cross-sectional view of the ceramic layer 10 shown in Figure 1. [Figure 3A] Figure 3A is a conceptual diagram showing an example of line analysis in a cross-section of a dielectric composition. [Figure 3B] Figure 3B is a graph showing an example of line analysis results. [Figure 4] Figure 4 is a graph showing the relationship between CIE / CD and the P-TV index (pulse withstand voltage index). [Modes for carrying out the invention]

[0013] The present disclosure will now be described in detail based on the embodiments shown in the drawings.

[0014] In this embodiment, a multilayer ceramic capacitor 2 shown in Figure 1 will be described as an example of an electronic component containing the dielectric composition according to this disclosure. The multilayer ceramic capacitor 2 has an element body 4 and a pair of external electrodes 6 formed on the outer surface of the element body 4.

[0015] The shape of the element body 4 shown in Figure 1 is typically a roughly rectangular parallelepiped, having two opposing end faces 4a in the X-axis direction, two opposing side faces 4b in the Y-axis direction, and two opposing side faces 4b in the Z-axis direction. However, the shape of the element body 4 is not particularly limited and may be elliptical, cylindrical, or other prismatic shapes. The external dimensions of the element body 4 are also not particularly limited; for example, the length L0 in the X-axis direction may be 0.4 mm to 5.7 mm, the width W0 in the Y-axis direction may be 0.2 mm to 5.0 mm, and the height T0 in the Z-axis direction may be 0.2 mm to 3.0 mm. In this embodiment, the X-axis, Y-axis, and Z-axis are perpendicular to each other.

[0016] The element body 4 has a ceramic layer 10 and an internal electrode layer 12 that are substantially parallel to a plane including the X and Y axes, and inside the element body 4, the ceramic layer 10 and the internal electrode layer 12 are stacked alternately along the Z axis. Here, "substantially parallel" means that most of the parts are parallel, but there may be some parts that are not parallel, and the ceramic layer 10 and the internal electrode layer 12 may have some irregularities or be tilted.

[0017] The ceramic layer 10 is composed of a dielectric composition described later. The average thickness per layer of the ceramic layer 10 (interlayer thickness) is not particularly limited and may be, for example, 100 μm or less, preferably less than 4 μm, and more preferably 2 μm or less. The number of layers of the ceramic layer 10 can be determined according to the desired characteristics and is not particularly limited. For example, the number of layers of the ceramic layer 10 is preferably 20 or more, and more preferably 50 or more.

[0018] On the other hand, the internal electrode layer 12 is laminated between each ceramic layer 10, and the number of layers is determined according to the number of ceramic layers 10. The average thickness of each layer of the internal electrode layer 12 is not particularly limited, but is preferably 3.0 μm or less. The average thickness of the ceramic layer 10 and the average thickness of the internal electrode layer 12 can be calculated by observing the cross-section as shown in Figure 1 using a metallurgical microscope and measuring the thickness of each layer (10, 12) at at least five locations.

[0019] Furthermore, the internal electrode layers 12 are stacked such that one end of each layer alternately exposes two opposing end faces 4a of the element body 4 in the X-axis direction. A pair of external electrodes 6 are formed on one end face 4a of the element body 4 and are electrically connected to the exposed ends of the alternately arranged internal electrode layers 12. By forming the internal electrode layers 12 and external electrodes 6 in this way, a capacitor circuit is formed by the external electrodes 6 and the internal electrode layers 12. That is, the ceramic layer 10 located within the capacitance region is sandwiched between internal electrode layers 12 with different polarities, and a voltage can be applied to the ceramic layer 10.

[0020] The internal electrode layer 12 is made of a conductive material, preferably containing Cu or Ni as the main component, and more preferably containing Ni as the main component. When the main component of the internal electrode layer 12 is Ni, the conductive material of the internal electrode layer 12 is preferably pure Ni or a Ni-based alloy containing 85 wt% or more Ni, and the Ni-based alloy may contain minor component elements such as Cu and Cr.

[0021] Furthermore, in addition to the conductive material described above, the internal electrode layer 12 may also contain particles of a perovskite-type compound having a composition similar to that of the main component of the ceramic layer 10 as a co-material. In addition, the internal electrode layer 12 may contain trace amounts of nonmetallic elements such as S and P (for example, about 0.1 mass% or less), and may also contain voids. When co-materials or voids are included in the internal electrode layer 12, discontinuous portions where electrodes (conductive material) are absent may be formed in the internal electrode layer 12.

[0022] The pair of external electrodes 6 may include a baked electrode layer, a resin electrode layer, a plated electrode layer, etc., and may consist of a single electrode layer or multiple electrode layers stacked together. For example, the external electrode 6 can have a three-layer structure (stacked in the order described) of a baked electrode layer containing Cu, a Ni plated layer, and a Sn plated layer. When this three-layer structure of external electrode 6 is formed, the Sn plated layer is located on the outermost surface of the external electrode 6, resulting in good solder wettability of the external electrode 6.

[0023] Furthermore, as shown in Figure 1, each external electrode 6 integrally comprises an end face portion formed on the end face 4a of the element body 4 and an extension portion formed on one end of each side surface 4b in the X-axis direction. That is, each pair of external electrodes 6 is formed to wrap around from the end face 4a to the side surface 4b of the element body 4 and is insulated so as not to come into contact with each other in the X-axis direction.

[0024] Furthermore, the extension of the external electrode 6 is not mandatory, and the external electrode 6 may consist only of the end face portion. Alternatively, when the multilayer ceramic capacitor 2 is surface-mounted on a substrate, the extension of the external electrode 6 only needs to be formed on the side 4b facing the mounting surface of the substrate, and does not need to be formed on the side 4b opposite the mounting surface.

[0025] Next, the dielectric composition of the ceramic layer 10 will be described in detail.

[0026] The dielectric composition of the ceramic layer 10 has the compositional formula [(Ca x Sr (1-x) )O〕 m [(Ti y Hf z Zr (1-y-z) The dielectric composition contains a main component represented by [O2]. This main component has a perovskite structure, with Ca and Sr being the elements that constitute the A site of the perovskite structure (ABO3), and Zr, Ti, and Hf being the elements that constitute the B site of the perovskite structure. Note that the main component of the dielectric composition (i.e., the main component of the ceramic layer 10) refers to the component that accounts for 80 mol% or more in the ceramic layer 10.

[0027] In the above compositional formula, m, x, y, and z respectively represent element ratios. Specifically, m represents the ratio of the A site to the B site. In this embodiment, m exceeds 1.020. By making m greater than 1.020, the pulse withstand voltage characteristics tend to improve. Also, m is preferably 1.024 or more and 1.040 or less, and more preferably 1.024 or more and 1.030 or less. By setting m within the above preferred range, the sinterability and temperature characteristics of the dielectric composition are improved.

[0028] In the above compositional formula, x represents the element ratio of Ca in the A site. It is preferable that the main component satisfies 0.5 ≤ x ≤ 1.0, and more preferably 0.6 ≤ x ≤ 0.9. Also, in the above compositional formula, y represents the element ratio of Ti in the B site, and z represents the element ratio of Hf in the B site. It is preferable that the main component of the dielectric composition satisfies 0.01 ≤ y ≤ 0.10, and more preferably 0.02 ≤ y ≤ 0.07. Also, it is preferable that the main component of the dielectric composition satisfies 0.00 < z ≤ 0.20, and more preferably 0.00 < z ≤ 0.10.

[0029] When the main component of the dielectric composition has the above composition, good temperature characteristics can be obtained and the C0G characteristics can be satisfied. Also, the sinterability of the dielectric composition is improved, and the generation of cracks can be suppressed.

[0030] The dielectric composition of the ceramic layer 10 contains Si, Al, and Mn as sub-components. These sub-components all originate from compounds added as sintering aids during the manufacturing process and exist in the form of oxides or composite oxides in the sintered ceramic layer 10. In this embodiment, the content rates of the above sub-components in the dielectric composition (i.e., the sintered ceramic layer 10) are shown in terms of oxide conversion respectively. Specifically, the content rate of Si is shown in terms of SiO2 conversion, the content rate of Al is shown in terms of Al2O3 conversion, and the content rate of Mn is shown in terms of MnO conversion.

[0031] The total content of Si, Al, and Mn in the dielectric composition is expressed as S in terms of oxides. T Therefore, the total content S T The amount of the auxiliary component can be 1 to 5 parts by weight per 100 parts by weight of the main component, and is preferably between 1.00 part by weight and 1.53 parts by weight. By keeping the total content of the three types of auxiliary components within the above range, it is possible to improve sinterability while ensuring dielectric properties.

[0032] Total content rate S T The ratio of Si (i.e., the ratio of SiO2) is S Si The total content S T The ratio of Al to (i.e., the ratio of Al2O3) is S Al The total content S T The ratio of Mn to MnO (i.e., the ratio of MnO) is S Mn Let's assume that. S Si The total content is S T It is preferable that the amount is 35 to 40 parts by weight, and more preferably 35 to 38 parts by weight, per 100 parts by weight. Al The total content is S T It is preferably 2 to 15 parts by weight, and more preferably 9 to 12 parts by weight, per 100 parts by weight. Also, S Mn This can be 45 to 63 parts by weight, preferably 51.3 parts by weight or more and 63.0 parts by weight or less, and more preferably 51.3 parts by weight or more and 57.3 parts by weight or less.

[0033] Furthermore, the dielectric composition of the ceramic layer 10 may contain other minor components in addition to the aforementioned minor components (Si, Al, and Mn). Examples of other minor components include Mg compounds, Cr compounds, Ni compounds, compounds containing rare earth elements, Li compounds, B compounds, V compounds, and Na compounds. The types and combinations of other minor components, as well as their content, are not particularly limited.

[0034] The component composition of the ceramic layer 10 can be analyzed using methods such as inductively coupled plasma atomic emission spectrometry (ICP), laser ablation ICP mass spectrometry (LA-ICP-MS), X-ray fluorescence analysis (XRF), energy-dispersive X-ray analysis (EDX), or an electron beam microanalyzer (EPMA) equipped with a wavelength-dispersive X-ray spectrometer (WDS).

[0035] The ceramic layer 10 containing the above dielectric composition has an internal structure as shown in Figure 2, and the ceramic layer 10 includes dielectric particles 20, a segregation phase 30 having predetermined characteristics, and a grain boundary phase 21 located between the dielectric particles 20.

[0036] The dielectric particles 20 are the matrix phase in the dielectric composition and contain the main components of the ceramic layer 10 described above. In addition to the main components, the dielectric particles 20 may also contain sub-components in solid solution. Furthermore, the dielectric particles 20 may have a core-shell structure due to the solid solution of other sub-components such as rare earth elements. The average particle size of the dielectric particles 20 is not particularly limited and may be, for example, 5 μm or less, and is preferably between 0.10 μm and 2.00 μm.

[0037] The average particle size of the dielectric particles 20 can be measured by observing a cross-section of the ceramic layer 10, as shown in Figure 2, using a scanning transmission electron microscope (STEM) or scanning electron microscope (SEM), and then performing image analysis on the resulting cross-sectional photograph. For example, the average particle size of the dielectric particles 20 can be calculated by measuring the equivalent circular diameter of at least five dielectric particles 20.

[0038] The segregated phase 30 is a composite oxide phase (secondary phase) containing at least Ca, Si, and O (oxygen). The term "segregated phase" refers to a phase in which a specific element is present at a higher concentration than the dielectric particles 20, which are the matrix phase. The Ca-Si-O segregated phase 30 can be classified into a first segregated phase 31 containing Mn and a second segregated phase 32 substantially free of Mn. Here, "substantially free of Mn" means that the Mn content in the segregated phase is less than 1.00 mol% in terms of MnO. Mn content in the first segregated phase 31:Mn The amount is 1.00 mol% or more, preferably 10 mol% or more, and more preferably 10 mol% or more and 66.7 mol% or less, in terms of MnO.

[0039] The first segregation phase 31 preferably contains (Ca,Mn)2SiO4. Furthermore, the Si content in the first segregation phase 31 is expressed as M in terms of SiO2. Si If expressed as (mol%), the ratio of Mn to Si in the first segregation phase 31 is (M Mn / M Si The ratio of ) is preferably greater than 0.38 and less than or equal to 1.30, and more preferably between 0.40 and 1.0. In addition to the elements mentioned above (Ca, Si, Mn, O), the first segregated phase 31 may also contain Sr, Zr, Ti, Hf, and Al.

[0040] The second segregation phase 32 preferably contains Ca2SiO4, and in addition to the elements mentioned above (Ca, Si, O), the second segregation phase 32 may also contain Sr, Zr, Ti, Hf, and Al.

[0041] In this embodiment, the content of the segregation phase 30 in the dielectric composition (i.e., the ceramic layer 10) is expressed as the number of segregation phases 30 contained in a predetermined cross-sectional area of ​​the dielectric composition, with the number of first segregation phases 31 being N1 and the number of second segregation phases 32 being N2. The ratio of N1 to the sum of N1 and N2 (N1 / (N1+N2)) is greater than 0.23 and less than or equal to 1.00. The presence of the first segregation phase containing Mn in the dielectric composition at the above ratio can reduce the failure rate of pulse breakdown voltage compared to conventional methods. It is preferable that N1 / (N1+N2) be 0.72 or more and less than 1.00, and more preferably 0.72 or more and less than 0.96.

[0042] The content of segregation phase 30 (total content of first segregation phase 31 and second segregation phase 32) per unit cross-sectional area of ​​the dielectric composition is 0.05 particles / μm 2 More than 0.50) pieces / μm 2 Preferably, the following is true: 0.07 particles / μm 2 More than 0.13 pieces / μm2 The following is more preferable. Furthermore, the content of the first segregation phase 31 in a unit cross-sectional area of ​​the dielectric composition is 0.05 particles / μm 2 More than 0.20 pieces / μm 2 Preferably, the following is true: 0.05 particles / μm 2 More than 0.12 pieces / μm 2 The following is more preferable:

[0043] Furthermore, the segregated phase 30 can be identified by mapping analysis using EDX or EPMA. For example, a cross-section of the device body 4, as shown in Figure 2, is observed with SEM or STEM, and mapping analysis is performed on the observed cross-section using EDX or EPMA during the observation. Then, a mapping image of each element constituting the dielectric composition is obtained by this mapping analysis. In the mapping image, regions with a high abundance ratio of a predetermined element, i.e., regions where the predetermined element is segregated, can be identified by the intensity of the color. In the segregated phase 30, the Ca concentration and Si concentration are higher than the concentrations in the dielectric particles 20, so by superimposing the Ca mapping image and the Si mapping image, the region where Ca and Si are segregated in overlapping areas can be identified as the segregated phase 30.

[0044] Furthermore, when identifying the segregated phase 30 through mapping analysis, the first segregated phase 31 and the second segregated phase 32 can be classified. For example, by superimposing mapping images of Ca, Si, and Mn, the region where Ca, Si, and Mn are segregated in overlapping areas can be identified as the first segregated phase 31, and the region where Ca and Si are segregated in overlapping areas, but Mn is not segregated, can be identified as the second segregated phase 32. Alternatively, after identifying the region where Ca and Si are segregated in overlapping areas as the segregated phase 30, point analysis can be performed on each segregated phase 30, and M Mn A segregation phase 30 having 1.00 mol% or more is identified as the first segregation phase 31, M Mn A segregated phase 30 having less than 1.00 mol% may be identified as the second segregated phase 32.

[0045] The mapping analysis described above is preferably performed across multiple fields of view. In particular, when calculating N1 / (N1+N2), a total of at least 100 μm should be used. 2 It is preferable to measure N1 and N2 by performing mapping analysis on the cross-section and identifying the first segregation phase 31 and the second segregation phase 32 contained within the analysis field. Furthermore, the composition of the segregation phase 30 can be measured by performing point analysis by EDX or EPMA after identifying the segregation phase 30 by mapping analysis. Mn / M Si Preferably, point analysis is performed on at least two first segregation phases 31 and the average value is calculated.

[0046] The minor components of the dielectric composition, Si, Al, and Mn, are not only contained in secondary phases such as the segregation phase 30, but are also solid-dissolved in the matrix phase, which consists of dielectric particles 20 and grain boundary phases 21. Furthermore, these minor components may diffuse during firing and be contained not only in the ceramic layer 10 but also in the internal electrode layer 12. In the element body 4 of the multilayer ceramic capacitor 2, it is particularly preferable that Mn is distributed in such a way that it satisfies the following requirements.

[0047] The Mn content in the ceramic layer 10 is C D (Assuming mol%), the Mn content in the internal electrode layer 12 is C IE (as mole%), C D C for IE The ratio (C IE / C D ) is less than 1.51, preferably 0.90 or less, and more preferably 0.80 or less. The diffusion of Mn into the internal electrode layer 12 is as described above C IE / C D By suppressing it to the extent that it satisfies the requirements, the failure rate of pulse withstand voltage can be reduced. IE / C D The lower limit is not particularly limited, but for example, C IE / C D It is preferable that the value is 0.40 or higher.

[0048] C above Dand C IE This can be calculated by quantitative analysis using EDX or EPMA. For example, at least 10 measurement points can be specified in any cross-section of the ceramic layer 10, avoiding segregation, and the average value of the analysis results at each measurement point can be used to calculate C D You can then calculate the following. Similarly, in the cross-section of the internal electrode layer 12, specify at least 10 measurement points so as to avoid segregation, and take the average value of the analysis results at each measurement point to get C IE You just need to calculate that.

[0049] Within the ceramic layer 10, Mn is distributed not only in the segregation phase 30 but also in the dielectric particles 20 and the grain boundary phase 21. In regions of the ceramic layer 10 other than the segregation phase 30, it is preferable that Mn is more abundant in the grain boundary phase 21. In other words, it is preferable that the Mn concentration in the grain boundary phase 21 is higher than the Mn concentration inside the dielectric particles 20. In the cross-section of the ceramic layer 10, the average Mn concentration (MD) near the center of the dielectric particles 20 is... P ), and the average Mn concentration of the grain boundary phase 21 (MD B When measuring ) MD P <MD B Preferably, it is 0.3 wt% < (MD B -MD P It is more preferable that it be )

[0050] Furthermore, it is preferable that the dielectric particles 20 have a concentration gradient in which the Mn concentration continuously decreases from the grain boundary side toward the center of the particle. This Mn concentration gradient can be analyzed by performing line analysis by EDX or EPMA when observing the cross-section of the ceramic layer 10 using SEM or STEM. For example, as shown in Figure 3A, a measurement line ML is drawn connecting the centers of two adjacent dielectric particles 20 across the grain boundary phase 21. Then, component analysis is performed at regular intervals along this measurement line ML. It is preferable to set the interval between measurement points to 0.05 μm to 0.2 μm. In this line analysis, the concentration change of the detected element along the measurement line ML can be analyzed. In other words, it is possible to analyze how each constituent element of the dielectric composition is distributed from the grain boundary phase 21 toward the center of the dielectric particle 20.

[0051] The graph shown in Figure 3B is an example of line analysis results. In Figure 3B, measurement point P0 is the grain boundary phase 21, and measurement point P C and P C ′ represents the vicinity of the center of the dielectric particle 20. As shown in Figure 3B, the Mn concentration reaches a local maximum in the grain boundary phase 21. The Mn concentration then gradually decreases from the grain boundary phase 21 toward the center of the dielectric particle 20.

[0052] Here, "the dielectric particle 20 has a concentration gradient of a predetermined element" means that, in the line analysis described above, the concentration of the predetermined element continuously increases or decreases from the grain boundary toward the center of the particle with a gradient (absolute value of slope) of |0.5|wt% / μm or more. Even if the concentration of the predetermined element increases or decreases within a particle, if the concentration of the predetermined element does not continuously increase or decrease along the measurement line ML, it is determined that "a concentration gradient does not substantially exist." Furthermore, even if the concentration of the predetermined element continuously increases or decreases within a particle, if the gradient between measurement points is not continuously |0.5|wt% / μm or more, it is determined that "a concentration gradient does not substantially exist." In other words, "the dielectric particle 20 does not substantially have a concentration gradient of a predetermined element" means that the concentration of the predetermined element does not continuously increase or decrease from the grain boundary toward the center of the particle, or that the concentration of the predetermined element continuously increases or decreases, but the gradient is less than |0.5|wt% between at least some measurement points.

[0053] In the graph of Mn concentration shown in Figure 3B, the Mn concentration gradually decreases from the grain boundary phase 21 toward the center of the dielectric particle 20, and the gradient (slope) between each measurement point is 0.5 wt% or more in absolute value. Therefore, it can be seen that both dielectric particles 20 located on the measurement line have a Mn concentration gradient. On the other hand, in the graph shown in Figure 3B, although the Al concentration increases and decreases somewhat within the dielectric particle 20, the gradient between each measurement point is not continuously 0.5 wt% or more. Thus, it is preferable for the dielectric particle 20 to have a Mn concentration gradient, and it is preferable that it does not substantially have an Al concentration gradient.

[0054] The Mn concentration in the grain boundary phase 21 is higher than that of the dielectric particles 20, and the dielectric particles 20 have a Mn concentration gradient, which can further improve the bonding strength between adjacent dielectric particles 20. It is preferable that the Mn concentration gradient shown in Figure 3B is observed in 70% or more of the dielectric particles 20 contained in the ceramic layer 10.

[0055] The grain boundary phase 21 includes two-particle grain boundaries located between two dielectric particles 20 and grain boundary multipoints located between three or more dielectric particles 20. Both the two-particle grain boundaries and grain boundary multipoints are composed of the main constituent elements and minor constituent elements. In addition to the Ca-Si-O segregated phase 30 described above, the ceramic layer 10 may also contain other segregated phases or voids. Examples of other segregated phases include segregated phases containing Zr, segregated phases containing Al, and segregated phases containing other minor constituent elements such as Mg or rare earth elements.

[0056] Next, an example of a manufacturing method for the multilayer ceramic capacitor 2 shown in Figure 1 will be described.

[0057] First, let's explain the manufacturing process for the element body 4. In the manufacturing process for the element body 4, a dielectric paste that will become the ceramic layer 10 after firing and an internal electrode paste that will become the internal electrode layer 12 after firing are prepared.

[0058] Dielectric pastes are manufactured using a perovskite-type compound powder (hereinafter referred to as the main component powder), which is the main component of the dielectric composition, and a secondary component powder that functions as a sintering aid. The main component powder can be manufactured by solid-phase methods, hydrothermal synthesis methods, or sol-gel methods. For example, in the solid-phase method, the main component powder is obtained by uniformly mixing starting materials such as CaCO3 powder, SrCO3 powder, ZrO2 powder, and TiO2 powder by wet mixing, and then calcining. At this time, the calcined main component powder may be subjected to appropriate processing such as grinding or classification.

[0059] As auxiliary component powders to be added to the dielectric paste, SiO2 powder, Al2O3 powder, and Mn compound powder (preferably MnCO3 powder, MnO powder, MnO2 powder, or Mn3O4 powder, more preferably MnCO3 powder) can be used, and these powders are S T S Si S Al , and S MnThe weight is weighed to the desired value. Alternatively, Ca-Mn-Si-O composite oxide powder and Ca-Si-O composite oxide powder may be used as auxiliary component powders. These composite oxide powders can be manufactured by mixing SiO2 powder, Al2O3 powder, and Mn compound powder in a predetermined ratio and performing a calcination treatment. In this case, it is preferable to subject the calcined composite oxide powder to treatments such as grinding and classification. When composite oxide powder is used as an auxiliary component powder, the content of each segregated phase (31, 32) in the ceramic layer 10 (i.e., N1 and N2) can be controlled by the mixing ratio of Ca-Mn-Si-O powder and Ca-Si-O powder.

[0060] The dielectric paste can be obtained by adding the above-mentioned main component powder and secondary component powder to an organic vehicle and kneading them together. Here, the organic vehicle is a binder dissolved in an organic solvent. The binder used is not particularly limited and can be appropriately selected from various binders such as polyvinyl butyral, acrylic, and ethylcellulose. The organic solvent used is also not particularly limited and can be appropriately selected from various organic solvents such as methyl ethyl ketone, methanol, ethanol, acetone, toluene, terpineol, and butyl carbitol.

[0061] Although the dielectric paste described above is an organic paint, the dielectric paste may also be a water-based paint using a water-based vehicle. In this case, the water-based vehicle is prepared by dissolving a water-soluble binder or dispersant in water. The water-soluble binder used is not particularly limited; for example, polyvinyl alcohol, water-soluble acrylic resin, water-soluble polyvinyl butyral resin, etc., can be used.

[0062] Furthermore, when adding other minor components besides Si, Al, and Mn to the ceramic layer 10, compound powders containing the other minor components may be added to the dielectric paste. In addition, the dielectric paste may contain additives selected from various dispersants, plasticizers, glass frit, etc., as needed.

[0063] The paste for the internal electrode can be manufactured by kneading conductive powder together with an organic vehicle or an aqueous vehicle. For example, if the main component of the internal electrode layer 12 is Ni, the paste for the internal electrode can be obtained by kneading conductive materials such as pure Ni powder or Ni alloy powder, or various oxides, organometallic compounds, or resinates that become Ni or a Ni alloy after firing, together with an organic vehicle. In this case, the main component powder contained in the dielectric paste may be added to the internal electrode paste as a co-material. The co-material has the effect of suppressing the sintering of the conductive powder during the firing process.

[0064] Next, a ceramic green sheet is obtained by forming a dielectric paste into a sheet using a method such as the doctor blade method. Then, an internal electrode paste is applied to this ceramic green sheet in a predetermined pattern using various printing methods such as screen printing or transfer methods. Furthermore, a mother laminate is obtained by stacking multiple layers of green sheets with the internal electrode pattern formed on them and then pressing them in the stacking direction. At this time, the ceramic green sheet and the internal electrode pattern are stacked so that the top and bottom surfaces of the mother laminate are located in the stacking direction.

[0065] The mother laminate obtained through the above process is cut to predetermined dimensions by dicing or press cutting to obtain multiple green chips. The green chips may be solidified and dried as needed to remove plasticizers, etc., or they may be barrel polished using a horizontal centrifugal barrel machine or the like after solidification and drying. In barrel polishing, the green chips are placed in a barrel container along with media and polishing fluid, and the barrel container is subjected to rotational motion or vibration. This barrel polishing polishes away unwanted parts such as burrs generated during cutting and rounds the corners of the green chips. After barrel polishing, the green chips are washed with a cleaning solution such as water and dried. Note that this barrel polishing may also be performed after the firing of the green chips.

[0066] Next, the green chip obtained above is subjected to a binder removal treatment, a firing treatment, and an annealing treatment to obtain the element body 4.

[0067] The conditions for the binder removal process can be appropriately determined according to the type of binder added to the dielectric paste and the internal electrode paste, and are not particularly limited. For example, the heating rate is preferably 5 to 300°C / hour (more preferably 10 to 100°C / hour), the holding temperature is preferably 180 to 400°C (more preferably 200 to 300°C), and the temperature holding time is preferably 0.5 to 24 hours (more preferably 5 to 20 hours). The binder removal atmosphere can be an atmospheric atmosphere (i.e., in air) or a reducing atmosphere, and an atmospheric atmosphere is preferred.

[0068] Regarding the firing process, conditions such as holding temperature and oxygen partial pressure are thought to affect the diffusion of Mn, so it is preferable to set the conditions to the optimal level according to the main component composition of the internal electrode layer 12. For example, if the main component of the internal electrode layer 12 is Ni, the holding temperature during firing can be 1100°C to 1350°C, and 1200°C to 1300°C is more preferable. Also, the oxygen partial pressure during firing is 2.0 × 10⁻⁶ -13 atm or more 1×10 -9 It can be less than or equal to atm, 1.0 × 10 -12 It is preferable to set the oxygen partial pressure to atm or higher. Conventionally, it has been considered desirable to keep the oxygen partial pressure during firing as low as possible in order to suppress the oxidation of Ni, but in this embodiment, it is more preferable to carry out firing in a weakly reducing atmosphere with a higher oxygen partial pressure than conventional methods.

[0069] For firing conditions other than those mentioned above, the temperature holding time is preferably 0.5 to 8 hours, and more preferably 1 to 3 hours. The heating rate and cooling rate are preferably 50 to 500°C / hour, and more preferably 200 to 300°C / hour. Furthermore, it is preferable to use a humidified mixture of N2 and H2 as the atmospheric gas.

[0070] After firing, it is preferable to perform an annealing treatment to relieve the stress generated inside the element body 4. In the annealing treatment, for example, it is preferable to reach a temperature of 600°C to 1000°C and an oxygen partial pressure of 1.0 × 10⁻⁶ -10 atm~1.0×10 -8 It is preferable to use atm. Furthermore, it is preferable to have a temperature holding time of 20 hours or less, and more preferably 2 to 10 hours. The heating rate and cooling rate are preferably 50 to 500°C / hour, and more preferably 100 to 300°C / hour. Furthermore, it is preferable to use dry N2 gas or humidified N2 gas as the atmospheric gas.

[0071] In the debinding, firing, and annealing processes described above, a wetter or similar device can be used to humidify the N2 gas or mixed gas, and in this case, a water temperature of approximately 5 to 75°C is preferable. Furthermore, the debinding, firing, and annealing processes may be performed continuously or independently.

[0072] Next, a pair of external electrodes 6 are formed on the outer surface of the element body 4 obtained above. The method for forming the external electrodes 6 is not particularly limited. For example, when forming baked electrodes as external electrodes 6, a conductive paste containing glass frit is applied to the end face of the element body 4 by a dip method, and then the element body 4 is heated to a predetermined temperature. Alternatively, when forming resin electrodes as external electrodes 6, a conductive paste containing thermosetting resin is applied to the end face of the element body 4, and then the element body 4 is heated to a temperature at which the thermosetting resin hardens. Furthermore, after forming baked electrodes or resin electrodes by the above method, sputtering, vapor deposition, electrolytic plating, or electroless plating may be performed to form external electrodes 6 having a multilayer structure.

[0073] Through the above process, a multilayer ceramic capacitor 2 having an external electrode 6 is obtained.

[0074] (Summary of the embodiments) The dielectric composition according to this embodiment has the compositional formula [(Ca x Sr(1-x) )O〕 m 〔(Ti y Hf z Zr (1-y-z) )O2〕-represented main component (1.020 < m), dielectric particles 20 containing the same, a grain boundary phase 21 located between the dielectric particles 20, and a segregation phase 30 containing at least Ca, Si, and O (oxygen). The segregation phase 30 can be classified into a first segregation phase 31 containing Mn and a second segregation phase 32 substantially free of Mn. Taking the number of the first segregation phase 31 contained in a predetermined cross-sectional area of the dielectric composition as N1 and the number of the second segregation phase 32 as N2, the dielectric composition of the present embodiment satisfies 0.23 < (N1 / (N1 + N2)) ≤ 1.00.

[0075] Further, the multilayer ceramic capacitor 2 according to the present embodiment has an element body 4 in which ceramic layers 10 and internal electrode layers 1 and 2 are alternately laminated, and each ceramic layer 10 contains the above dielectric composition. In the multilayer ceramic capacitor 2, the content ratio C of Mn in the ceramic layer D (mol%) to the content ratio C of Mn in the internal electrode layer IE (mol%) of the ratio (C IE / C D ) is less than 1.51.

[0076] As a result of intensive studies by the inventors of the present disclosure, it has been found that the distribution of Mn in the element body 4 affects the pulse withstand voltage failure. Specifically, in a conventional multilayer ceramic capacitor, Mn added as a sintering aid to the dielectric composition diffuses into the internal electrode layer during firing, resulting in insufficient bonding between dielectric particles, which is considered to cause pulse withstand voltage failure. In particular, when the thickness of the ceramic layer is less than 4 μm, diffusion of Mn into the internal electrode layer is likely to occur, and pulse withstand voltage failure is likely to occur. In the multilayer ceramic capacitor 2 of the present embodiment, by dispersing the first segregation phase 31 in which Mn is dissolved and the second segregation phase 32 not containing Mn at a predetermined ratio, the ratio of Mn remaining in the ceramic layer 10 increases, and the bonding between the dielectric particles 20 is considered to be strengthened. As a result, the failure rate of the pulse withstand voltage can be reduced as compared with the conventional case.

[0077] In particular, the ratio of Mn to Si in the first segregation phase 31 (M Mn / M Si By setting the value between 0.38 and 1.30, the failure rate of pulse withstand voltage can be further reduced.

[0078] Furthermore, in the ceramic layer 10 of the multilayer ceramic capacitor 2, it is preferable that the Mn concentration in the grain boundary phase 21 is higher than the Mn concentration inside the dielectric particles 20, and that the dielectric particles 20 have a Mn concentration gradient. Although Si and Al are also minor components that contribute to sinterability, it is thought that dispersing Mn as described above, rather than Si or Al, makes the bonds between the dielectric particles 20 stronger, and thus can further reduce the failure rate of pulse breakdown voltage.

[0079] In this embodiment, the multilayer ceramic capacitor 2 reduces pulse breakdown voltage failure while maintaining characteristics such as relative permittivity, dielectric loss tangent, and temperature characteristics by dispersing the first segregation phase 31 and the second segregation phase 32 in a predetermined ratio. Furthermore, the multilayer ceramic capacitor 2 can improve not only pulse breakdown voltage characteristics but also insulation resistance (IR) and dielectric breakdown voltage (BDV) compared to conventional capacitors.

[0080] While embodiments of this disclosure have been described above, this disclosure is not limited in any way to the embodiments described above and can be modified in various ways without departing from the gist of this disclosure.

[0081] For example, in this embodiment, a multilayer ceramic capacitor 2 is exemplified as a multilayer ceramic electronic component, but the dielectric composition of this disclosure may be applied to other electronic components on which a dielectric layer is formed. For example, other electronic components include bandpass filters, multilayer three-terminal filters, thermistors, varistors, and the like.

[0082] In addition, in this embodiment, the ceramic layer 10 and the internal electrode layer 12 are laminated in the Z-axis direction, but the lamination direction may be the X-axis direction or the Y-axis direction. In that case, the external electrode 6 may be formed in accordance with the exposed surface of the internal electrode layer 12. Further, the internal electrode layer 12 may be drawn out to the outer surface of the element body 4 via the through-hole electrode, and in this case, the through-hole electrode and the external electrode 6 are electrically joined.

Example

[0083] Hereinafter, the present disclosure will be described based on more detailed examples, but the present disclosure is not limited to these examples.

[0084] In this experiment, multilayer ceramic capacitors according to Samples 1 to 6 were manufactured according to the procedure shown below.

[0085] First, the main component powder, which is the raw material of the dielectric paste, was manufactured by the solid-phase method. Specifically, as starting materials, CaCO3 powder, SrCO3 powder, TiO2 powder, ZrO2 powder, and HfO2 powder were prepared, and these starting materials were weighed so that the main component after firing would have a desired composition. Then, the weighed starting materials were mixed and calcined, and the obtained calcined powder was pulverized with a ball mill to obtain a main component powder having an average particle size of 0.29 μm. The main component powder was made common for each of Samples 1 to 6.

[0086] Next, a dielectric paste was obtained by kneading the above main component powder, the sub-component powder, and the organic vehicle. In Sample 1, SiO2 powder, Al2O3 powder, and MnO powder were added to the dielectric paste as the sub-component powder, and in Samples 2 to 6, Ca-Si-O powder and Ca-Mn-Si-O powder were added to the dielectric paste as the sub-component powder. The blending ratio of the sub-component powder with respect to the main component powder was made common for Samples 1 to 6, and the blending ratio of the sub-component powder was controlled so that S T 、S Si 、S Mn 、and S Al would become the desired values in the fired ceramic layer.

[0087] Next, green sheets were prepared using the dielectric paste described above, and an internal electrode paste was applied to each green sheet in a predetermined pattern. The internal electrode paste was manufactured by kneading Ni powder and an organic vehicle. Multiple layers of green sheets with the internal electrode pattern were stacked and pressed from the stacking direction to obtain a mother laminate. At this time, protective green sheets without the internal electrode pattern were stacked on the top and bottom surfaces of the mother laminate. Multiple green chips were obtained by cutting the mother laminate to a predetermined size by dicing.

[0088] Next, the above-mentioned green chips were subjected to debindering, firing, and annealing to obtain the element body (fired body). The debindering and annealing treatments were carried out under common conditions for samples 1 to 6, with conditions such as the holding temperature set within the range described in the embodiment. For the firing treatment, all conditions except the oxygen partial pressure were common to each of samples 1 to 6, with a holding temperature of 1240°C, a temperature holding time of 2 hours, and a humidified N2+H2 atmosphere for firing. The oxygen partial pressure during firing was set to different values ​​for samples 1 to 6. Specifically, the oxygen partial pressure of sample 1 was 1.0 × 10⁻⁶. -12 The oxygen partial pressure was kept below atm, with the oxygen partial pressure of sample 2 being 16.2 times that of sample 1, sample 3 being 23.7 times that of sample 1, sample 4 being 8.9 times, sample 5 being 2.6 times that of sample 1, and sample 6 being 2.0 times that of sample 1.

[0089] Next, a pair of external electrodes was formed by applying an external electrode paste to each end face of the element body and baking it, thereby obtaining samples of multilayer ceramic capacitors. For each of samples 1 to 6, more than 20,000 multilayer ceramic capacitors were manufactured. The size of each capacitor manufactured for samples 1 to 6 was L0 × W0 × T0 = 3.2 mm × 1.6 mm × 1.6 mm. In each capacitor, the number of ceramic layers sandwiched between the internal electrode layers (number of layers) was 255, the average thickness of the ceramic layers was 2.9 μm, and the average thickness of the internal electrode layers was 1.0 μm.

[0090] The multilayer ceramic capacitors of each sample manufactured in this experiment were evaluated as follows.

[0091] composition of dielectric composition The main component composition and the content of minor components of the ceramic layer (dielectric composition) were analyzed using an X-ray fluorescence analyzer. As a result, the main component composition was consistent for each sample 1 to 6, and it was confirmed that the analytical values ​​after firing were in general agreement with the composition of the main component powder produced by the solid-phase method. Specifically, the main component composition for each sample 1 to 6 was all based on the composition formula [(Ca x Sr (1-x) )O〕 m [(Ti y Hf z Zr (1-y-z) It was represented as )O2, where m was 1.02-1.04, x was 0.5-1.0, y was 0.01-0.10, and z was 0-0.20.

[0092] Furthermore, the content of minor components was generally consistent across samples 1-6. Specifically, the total content S of Si, Al, and Mn in the ceramic layer of each sample was... T In all cases, the amount was 1 to 5 parts by weight per 100 parts by weight of the main component. In addition, S Si +S Al +S Mn =100 parts by weight, for each sample, S Si 35-40 parts by weight, S Mn This amounted to 45-63 parts by weight.

[0093] Cross-sectional analysis of capacitor samples EPMA mapping analysis was performed on a cross-section of the ceramic layer (dielectric composition) to identify the segregated phase contained within the ceramic layer. The measurement field of view for this mapping analysis was 382 μm². 2 The number of first segregation phases (Ca-Mn-Si-O segregation) N1 and the number of second segregation phases (Ca-Si-O segregation) N2 contained in the field of view were measured, and N1 / (N1+N2) was calculated for each sample.

[0094] Furthermore, quantitative analysis using EPMA revealed the Mn content C in the ceramic layer. D (mol%) and the Mn content C in the Ni internal electrode layer IE (mol%) is measured, and the C of each sample is determined from the measurement results. IE / C D The result was calculated.

[0095] Pulse withstand voltage characteristics In the pulse withstand voltage test, a pulsed DC voltage (test voltage) was applied to the manufactured capacitor samples, and the leakage current was measured. Each of the 1-6 samples consisted of 20,000 test samples, and the test voltage was set to be equal to or greater than the rated voltage. This test voltage was applied to each sample in both the positive and negative directions. In this pulse withstand voltage test, the pass / fail status of each sample was determined based on the leakage current. The number of NGs (test samples that failed the voltage test) when the positive test voltage was applied and the number of NGs when the negative test voltage was applied were added together to calculate the failure rate for each of the 1-6 samples. Then, using a failure rate of 5000 ppm as a baseline, the P-TV index (pulse withstand voltage index) for each of the 1-6 samples was calculated. For example, if the failure rate in the pulse withstand voltage test is 10,000 ppm, the P-TV index will be 200 (unitless), and if the failure rate in the pulse withstand voltage test is 2,500 ppm, the P-TV index will be 50 (unitless). A lower P-TV index indicates better pulse withstand voltage characteristics.

[0096] Measurement of relative permittivity ε and dielectric loss tangent tanδ Using an LCR meter, the capacitance and dielectric loss tangent tanδ (%) were measured at room temperature (measurement temperature 20°C). The relative permittivity ε (unitless) of the capacitor sample was then calculated based on the ceramic layer thickness, effective electrode area, and measured capacitance. This measurement was performed on 10 capacitor samples for each of the six samples (1-6), and the average values ​​were used to calculate ε and tanδ for each sample (1-6).

[0097] Measurement of Dielectric Breakdown Voltage (BDV) Furthermore, the dielectric breakdown voltage (BDV) of the capacitor samples was measured using the method described below. Specifically, the capacitor samples were placed in insulating oil at room temperature, and a DC current was applied to the capacitor samples at a predetermined boost rate. The voltage value (in V) at which the leakage current exceeded a predetermined reference value was measured. This measurement was performed on 50 capacitor samples for each of the six samples (1 to 6), and the average of the measurement results was calculated as the dielectric breakdown voltage (BDV) (in V) for each of the six samples (1 to 6).

[0098] Measurement of insulation resistance (IR) Furthermore, the insulation resistance (IR) of the capacitor samples was measured using the method described below. Specifically, a DC voltage of 50V was applied to the capacitor sample for 30 seconds at room temperature (20°C), and the resistance value (Ω) of the capacitor sample thereafter was measured using an insulation resistance meter. This measurement was performed on 10 capacitor samples for each of the 1 to 6 samples, and the average value of the measurement results (average resistance value) was calculated as the insulation resistance (IR) (Ω) for each of the 1 to 6 samples.

[0099] Table 1 shows the evaluation results for each sample (1-6). [Table 1]

[0100] In this experiment, sample 1 corresponds to the comparative example, and in sample 1, the N1 / (N1+N2) ratio, which indicates the proportion of the first segregation phase (Ca-Mn-Si-O segregation), was 0.23. On the other hand, in samples 2 to 6, the proportion of the first segregation phase was higher than in sample 1, and the P-TV index was reduced compared to sample 1. From these results, it was found that the dielectric composition constituting the ceramic layer can reduce the failure rate of pulse breakdown voltage compared to the conventional comparative example (sample 1) by satisfying 0.23 < (N1 / (N1+N2)) ≤ 1.00.

[0101] Furthermore, in comparative example sample 1, the C distribution in the element body is IE / C D The value was 1.51 or higher. On the other hand, in the examples, samples 2 to 6, C IE / CD The value was lower than that of sample 1. Figure 4 shows the evaluation results for each of samples 1 to 6 shown in Table 1, C IE / C D This is a graph plotting the relationship between C and the P-TV index. As shown in Figure 4, IE / C D It was found that the failure rate of pulse withstand voltage can be reduced by setting the value to less than 1.51.

[0102] Regarding characteristics other than pulse breakdown voltage, good results were obtained for all samples, regardless of the difference between the comparative example and the example. Furthermore, each of the multilayer ceramic capacitors from samples 1 to 6 possessed the C0G characteristics defined by the EIA standard. In other words, it was found that in the example (samples 2 to 6), which contained the first and second segregation phases in predetermined proportions, pulse breakdown voltage failure could be reduced compared to conventional methods while maintaining other characteristics such as ε, tanδ, VB, and IR. In particular, a slight improvement in dielectric breakdown voltage (BDV) and insulation resistance (IR) was observed in samples 2 to 6 (the example) compared to the comparative example (sample 1).

[0103] The line analysis results shown in Figure 3B are from the analysis of capacitor sample 3. In other words, in sample 3, a concentration gradient of Mn was observed in the dielectric particles, while a concentration gradient of Al in the dielectric particles was not substantially observed. Also, in sample 3, M in the first segregation phase Mn / M Si However, it was within the range of greater than 0.38 and less than or equal to 1.30. Sample 3, which had these characteristics, showed the lowest P-TV index among the examples, and the highest VB and IR values. [Explanation of Symbols]

[0104] 2… Multilayer ceramic capacitor 4… Click this button on the main body 4a … End face 4b…side 10… Ceramic layer 12 … Internal electrode layer 20… Dielectric particles 21 … Grain boundary phase 30 … Segregated phase 31 … First segregated phase 32 … Second segregated phase 6 … External electrodes

Claims

1. Composition formula [(Ca x Sr (1-x) )O〕 m [(Ti y HF z Zr (1-y-z) ) O 2 ] Principal components Dielectric particles containing, A grain boundary phase located between the dielectric particles, A segregated phase containing at least Ca, Si, and O (oxygen), The aforementioned composition formula satisfies 1.020 < m, x is 0.5 to 1.0, y is 0.01 to 0.10, and z is 0 to 0.

20. Of the aforementioned segregated phases, the segregated phase further containing Mn is designated as the first segregated phase, and the segregated phase substantially not containing Mn is designated as the second segregated phase. Let N1 be the number of first segregation phases contained in a predetermined cross-sectional area of ​​the dielectric composition, and N2 be the number of second segregation phases. A dielectric composition satisfying 0.23 < (N1 / (N1+N2)) ≤ 1.

00.

2. The Mn content in the first segregated phase is expressed as M in terms of MnO. Mn (Assuming mol%), The content rate of Si in the first segregation phase is expressed as M 2 in terms of SiO Si (mol%) The first segregation phase is 0.38 < (M Mn / M Si The dielectric composition according to claim 1, satisfying ) ≤ 1.

30.

3. The Mn concentration in the grain boundary phase is higher than the Mn concentration inside the dielectric particles. The dielectric composition according to claim 1 or 2, wherein the dielectric particles have a concentration gradient in which the Mn concentration decreases from the grain boundary toward the center of the particle, and substantially have no concentration gradient of Al.

4. A ceramic layer comprising the dielectric composition according to claim 1 or 2, and an internal electrode layer in contact with the ceramic layer, The Mn content in the aforementioned ceramic layer is C D (Assuming mol%), the Mn content in the internal electrode layer is C IE (As mole percent) (C IE / C D ) < Multilayer ceramic electronic component that satisfies 1.51.

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