Multilayer ceramic electronic components

Abstract

According to the present invention, an internal electrode layer 3 includes therein a plurality of inner ceramic particles 36a within an observation range of a cross-section intersecting the internal electrode layer 3. The position of the inner ceramic particles 36a in the internal electrode layer 3 relative to the center position of the internal electrode layer 3 in the thickness direction is correlated with the position from the center position to the edge position, and the corresponding positions are indicated by the numbers 0-100. Such an index is referred to as Dsp. Inside the internal electrode layer 3, within a region of Dsp of 40 or less, preferably 30 or less, the inner ceramic particles 36a are present in an area of at least 50% of the total area of the inner ceramic particles 36a present within the observation range.

Description

[Technical Field]

[0001] The present invention relates to a multilayer ceramic electronic component having alternatingly stacked ceramic layers and an internal electrode layer. [Background technology]

[0002] In multilayer ceramic capacitors, an example of multilayer ceramic electronic components, thinning the internal electrode layer, which is the internal conductive film, is effective in increasing capacitance and miniaturizing the component. The internal electrode layer is often formed by firing a conductive paste film containing conductive metal particles such as nickel particles, an organic solvent, and an organic binder simultaneously with a dielectric ceramic sheet.

[0003] In the firing process described above, there is usually a difference in shrinkage behavior during sintering between the metal component in the conductive paste film and the ceramic component in the dielectric ceramic sheet. More specifically, the ceramic component has a sintering temperature of 1000°C or higher, while the metal component, such as nickel, has a sintering temperature lower than 1000°C, for example, 600-800°C.

[0004] The difference in shrinkage behavior during sintering between the metal component in the conductive paste film and the ceramic component in the dielectric ceramic sheet leads to problems such as gaps forming in the internal electrode layer when the internal electrode layer is thinned. In other words, during the sintering process, the metal component begins to sinter before the ceramic component, and the metal component undergoes excessive grain growth before reaching the temperature at which the ceramic component begins to sinter, resulting in a decrease in the continuity of the internal electrode layer. This decrease in the continuity of the internal electrode layer leads to a decrease in the capacitance of the multilayer ceramic capacitor.

[0005] To solve the aforementioned problems, a method has been adopted in which ceramic particles called co-materials are added to the conductive paste used to form the internal electrodes in order to suppress the sintering of the metal components. With the recent trend towards thinner internal conductive films, there is a growing demand for these co-materials to have a particle size of 100 nm or less (see, for example, Patent Document 1).

[0006] However, the finer the ceramic particles used in the co-material, the more pronounced the aggregation of the ceramic particles becomes. Therefore, in the case of conductive paste manufactured using a batch mixing and dispersion process, if the particle size of the ceramic particles contained therein is reduced to, for example, 100 nm or less, it becomes difficult to uniformly arrange the fine ceramic particles around the conductive metal particles in the conductive paste due to the aggregation of the ceramic particles.

[0007] Thus, if fine ceramic particles cannot be uniformly arranged around conductive metal particles, sintering of the conductive metal particles will proceed from areas where ceramic particles are absent, making it difficult to achieve thinness and high continuity in the internal electrode layer formed using the conductive paste. [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] Japanese Patent Publication No. 2001-110233 [Overview of the Initiative] [Problems that the invention aims to solve]

[0009] This invention has been made in view of the above circumstances, and its purpose is to achieve thinning and high continuity. The objective is to provide a multilayer ceramic electronic component having an internal electrode layer that can perform the following actions. [Means for solving the problem]

[0010] The present inventors diligently studied multilayer ceramic electronic components having an internal electrode layer that can achieve thinness and high continuity. As a result, they discovered that the objective of the present invention can be achieved by dispersing and concentrating relatively small-particle-sized ceramic particles near the center in the thickness direction of the internal electrode layer, and thus completed the present invention.

[0011] In other words, a multilayer ceramic electronic component according to the first aspect of the present invention is A multilayer ceramic electronic component having alternatingly stacked ceramic layers and an internal electrode layer, Within the observation range of the cross-section that intersects with the aforementioned internal electrode layer, The internal electrode layer contains a plurality of internal ceramic particles inside, Dsp is an index that indicates the relative position of the inner ceramic particles within the internal electrode layer with respect to the central position in the thickness direction of the internal electrode layer, corresponding to the distance from the central position to the edge position, using a number from 0 to 100. Within the internal electrode layer, in a region where Dsp is 40 or less, preferably 30 or less, the internal ceramic particles are present in an area of ​​50% or more of the total area of ​​the internal ceramic particles that are present within the observation range.

[0012] In a first aspect of the present invention, within the internal electrode layer, more than 50% of the total area of ​​the internal ceramic particles present within the observation range is located in a region where Dsp is 40 or less, preferably 30 or less. That is, more than half (more than 50% of the area) of the internal ceramic particles present within the observation range are located in a region where Dsp is 40 or less, preferably 30 or less (near the center in the thickness direction). The inventors have confirmed that a multilayer ceramic electronic component having an internal electrode layer with such a configuration can simultaneously satisfy thinning of the internal electrode layer and high continuity. Furthermore, it has been confirmed that thinning of the ceramic layer (e.g., dielectric layer) laminated between the pair of internal electrode layers is achieved simultaneously with thinning of the internal electrode layer, and that variations in the thickness of these layers are also reduced.

[0013] A multilayer ceramic electronic component according to a second aspect of the present invention is: A multilayer ceramic electronic component having alternatingly stacked ceramic layers and an internal electrode layer, Within the observation range of the cross-section that intersects with the aforementioned internal electrode layer, The internal electrode layer contains a plurality of internal ceramic particles inside, An index Dsp is defined as a number from 0 to 100 corresponding to the relative position of the inner ceramic particles within the internal electrode layer with respect to the central position in the thickness direction of the internal electrode layer. Within the internal electrode layer, 99% or more of the total area of the inner ceramic particles present within the observation range is occupied by the inner ceramic particles in a region where Dsp is 75 or less, preferably 73 or less.

[0014] In a second aspect of the present invention, within the internal electrode layer, 99% of the total area of the inner ceramic particles present within the observation range is present in a region where Dsp is 75 or less, preferably 73 or less. That is, most (99% or more in terms of area) of the inner ceramic particles present within the observation range are present in a region where Dsp is 75 or less, preferably 73 or less. It has been confirmed by the inventors that a multilayer ceramic electronic component having an internal electrode layer with such a configuration can simultaneously satisfy the thinning and high continuity of the internal electrode layer. Also, simultaneously with the thinning of the internal electrode layer, the thinning of the ceramic layer (for example, a dielectric layer) laminated so as to be sandwiched between a pair of internal electrode layers is also achieved, and it has been confirmed that the thickness variation of these layers is reduced.

[0015] Preferably, the ratio of the total area of the inner ceramic particles to the total area of the internal electrode layer present within the observation range is 2.5% or less, more preferably 2% or less. According to a multilayer ceramic electronic component having an internal electrode layer with such a configuration, the coverage rate of the internal electrode layer with respect to the ceramic layer is improved, and the continuity of the internal electrode layer is further improved.

[0016] Preferably, the maximum particle size of the inner ceramic particles present within the observation range is 69 nm or less, more preferably 63 nm or less. The fact that the maximum particle size of the inner ceramic particles is below a predetermined value indicates that aggregation of co-material particles (ceramic particles before firing) with a fine particle size in the paste film for the internal electrode layer is suppressed. As a result of suppressing the aggregation of the co-material particles and firing the paste film for the internal electrode layer, abnormal grain growth of the conductive particles in the paste film is suppressed, contributing to thinning and thickness uniformity of the internal electrode layer, and further improving the continuity of the internal electrode layer.

[0017] Preferably, the number of the inner ceramic particles per area of 50 μm 2 of the internal electrode layer present within the observation range is 185 or less, more preferably 170 or less, and is, for example, within the range of 55 to 166. By controlling the number of the inner ceramic particles, it contributes to thinning, improves the coverage rate of the internal electrode layer with respect to the ceramic layer, and further improves the continuity of the internal electrode layer.

Brief Description of the Drawings

[0018] [Figure 1] FIG. 1 is a cross-sectional view of a multilayer ceramic capacitor according to an embodiment of the present invention. [Figure 2] FIG. 2 is a partially enlarged photograph of a laminated cross-section of the dielectric layer and the internal electrode layer shown in FIG. 1. [Figure 3] FIG. 3 is a schematic diagram schematically enlarging a part of the internal electrode layer shown in FIG. 2. [Figure 4] FIG. 4 is a schematic diagram for explaining Dsp of the inner ceramic particles included in a part of the internal electrode layer as shown in FIG. 3. [Figure 5] FIG. 5 is a graph showing the relationship between Dsp of each inner ceramic particle shown in FIG. 2 and the area cumulative frequency of the inner ceramic particles. [Figure 6] FIG. 6 is a schematic cross-sectional view of composite particles used for a paste for forming the internal electrode layer shown in FIG. 2. [Figure 7] FIG. 7 is an explanatory diagram for measuring the co-material coverage rate in the composite particles. [Figure 8] Figure 8 is an explanatory diagram for measuring the coverage rate of the same material, following Figure 7. [Figure 9] Figure 9 is an explanatory diagram for measuring the coverage rate of the same material, following Figure 8. [Modes for carrying out the invention]

[0019] The present invention will be described below based on the embodiments shown in the drawings. As an example of a multilayer ceramic electronic component, the multilayer ceramic capacitor 1 of this embodiment will be described. As shown in Figure 1, the multilayer ceramic capacitor 1 has a ceramic body 10 in which ceramic layers 2 and internal electrode layers 3 are stacked alternately along the Z-axis direction, with the ceramic layers 2 and internal electrode layers 3 substantially parallel to a plane including the X and Y axes.

[0020] Here, "substantially parallel" means that most of the parts are parallel, but it is acceptable for there to be some non-parallel parts. This means that the ceramic layer 2 and the internal electrode layer 3 may have some irregularities or be slightly tilted.

[0021] The internal electrode layer 3 is stacked so that each end is alternately exposed on the surface of two end faces located opposite each other along the X-axis of the ceramic body 10. The pair of external electrodes 4 are attached to the ceramic body Formed on both end faces of the X-axis of the 10, and connected to the exposed ends of each of the alternately arranged internal electrode layers 3, they constitute a capacitor circuit.

[0022] The conductive material for the external electrode contained in the external electrode 4 is not particularly limited, but in this embodiment, inexpensive Ni and Cu and their alloys can be used. The thickness of the external electrode 4 can be appropriately determined depending on the application, but is usually 10 to 50 μm.

[0023] The thickness of the ceramic layer 2 is not particularly limited, but is preferably 2 μm or less per layer, more preferably 1.5 μm or less, still more preferably 0.8 μm or less, and particularly preferably 0.5 μm or less. Also, the variation σ in the thickness of the ceramic layer 2 is preferably within 0.1 μm, more preferably within 0.063 μm, and particularly preferably within 0.05 μm.

[0024] Also, the thickness of the internal electrode layer 3 is not particularly limited, but is preferably 2 μm or less per layer, more preferably 1.0 μm or less, still more preferably 0.5 μm or less, and particularly preferably 0.5 μm or less. The lower limit of the thickness of the internal electrode layer 3 is preferably 0.298 μm or more, more preferably greater than 0.4 μm. Also, the variation σ in the thickness of the internal electrode layer 3 is preferably within 0.3 μm, more preferably within 0.23 μm, and particularly preferably within 0.1 μm.

[0025] The number of stacked layers of the ceramic layer 2 (internal electrode layer 3) is not particularly limited, but is preferably 20 or more, more preferably 50 or more.

[0026] Examples of the material of the ceramic layer 2 include dielectric ceramics mainly composed of components such as BaTiO3, CaTiO3, SrTiO3, CaZrO3, (K 1-x Na x )Sr2Nb5O 15 , Ba3TiNb4O 15 , (Ba 1-x Ca x )(Ti 1-y Zr y )O3 and the like. Also, auxiliary components such as Mn compounds, Mg compounds, Cr compounds, Co compounds, Ni compounds, rare earth elements, Si compounds, and Li compounds may be added to these main components.

[0027] The conductive components contained in the internal electrode layer 3 according to this embodiment are not particularly limited, and examples include nickel, nickel alloys, copper, copper alloys, silver, and silver alloys, but nickel or nickel alloys are preferred. The internal electrode layer 3 may also contain various trace components such as C, S, N, and O in amounts of about 1% by mass or less.

[0028] As shown in Figure 2, the ceramic layer 2, which is the insulating layer, has some variation in thickness along the Z-axis, but is almost continuous along the X and Y axes. The internal electrode layer 3, which is the conductive layer, may have electrode discontinuities 3b along the X or Y axis. Within the observation range of the cross-sectional photograph in Figure 2, the internal electrode layer 3 may consist of internal electrode portions 3a that appear discontinuous along the X or Y axis.

[0029] Although the internal electrode portion 3a appears discontinuous along the X or Y axis, it is actually connected in other cross-sections of the ceramic body 10 shown in Figure 1, and does not result in connection failure. However, the fewer the electrode breaks 3b, the better the coverage of the electrode layer 3 over the ceramic layer 2, and the better the characteristics such as capacitance. Generally, as the internal electrode layer 3 and ceramic layer 2 are thinned, electrode breaks 3b tend to occur more easily, and the electrode coverage tends to decrease.

[0030] The electrode coverage can be measured, for example, by the method shown in Figure 3. Figure 3 shows an enlarged schematic diagram of a certain internal electrode layer 3 in a cross-sectional photograph as shown in Figure 2. In Figure 3, as an example, it is assumed that within the observation range of the cross-sectional photograph, the internal electrode layer 3 of length L in the X-axis or Y-axis direction has two electrode breaks 3b. In this case, the electrode coverage is obtained by dividing the sum of the lengths L1, L2, L3 of each electrode portion 3a along the X-axis or Y-axis direction by the total length L of the internal electrode layer 3. The coverage can also be expressed in percentage form. Alternatively, the coverage may be calculated for a predetermined number of (e.g., 10 or more) internal electrode layers 3 within the observation range of the cross-sectional photograph, and the average value of these calculations may be obtained.

[0031] In this embodiment, while maintaining the thinness of the internal electrode layer 3, the electrode coverage rate can be preferably 70% or more, and more preferably 80% or more, within a predetermined cross-sectional observation range (for example, 12 μm × 8 μm). Furthermore, in this embodiment, within a predetermined cross-sectional observation range (for example, 12 μm × 8 μm), the number of electrode portions 3a per internal electrode layer (number of electrode divisions) is preferably 5 or less, more preferably 3 or less, and particularly preferably 2 or less.

[0032] As shown in Figures 2 and 4, relatively small-particle-sized ceramic particles 36a exist inside the electrode portion 3a of the internal electrode layer 3 in this embodiment. In Figure 2, the ceramic particles 36a are observed as black dots within the gray electrode portion 3a. Although not entirely clear in Figure 2, the ceramic layer 2 is actually formed by a series of ceramic particles that are relatively larger in particle size than the ceramic particles 36a. In this embodiment, to distinguish them from the ceramic particles of the ceramic layer 2, the ceramic particles 36a observed inside the electrode portion 3a of the internal electrode layer 3 will also be referred to as inner ceramic particles 36a.

[0033] In this embodiment, the inner ceramic particles 36a are dispersed within the inner electrode layer 3 and are located near the center in the thickness direction (approximately parallel to the Z-axis direction) of the inner electrode layer 3. In this embodiment, the index Dsp is used as an index to indicate the position of the inner ceramic particles 36a in the thickness direction within the inner electrode layer 3. The index Dsp can be obtained, for example, as follows.

[0034] For example, Figure 4 shows a schematic diagram obtained by extracting the electrode portion 3a of one internal electrode layer 3 from a cross-sectional photograph like the one shown in Figure 2. In Figure 4, for example, focusing on one inner ceramic particle 36a, a perpendicular line is drawn passing through the centroid of the particle 36a and parallel to the thickness direction (approximately parallel to the Z-axis direction) of the electrode portion 3a. The length from the point where this perpendicular line intersects the upper and lower edges of the electrode portion 3a is defined as the electrode width Z0. Next, the midpoint position (center position) O of the electrode width Z0 is determined, and the distance Z1 from the midpoint position O to the centroid position of the particle 36a is determined. The index Dsp is obtained by dividing the distance Z1 by the distance Z2 and expressing it as a percentage. Note that the distance Z2 is half the value of the distance Z0.

[0035] The Dsp can be automatically calculated for each ceramic particle 36a using an image processing algorithm. Furthermore, the area S0 of each ceramic particle 36a can also be automatically calculated using an image processing algorithm.

[0036] Dsp can be represented by a number between 0 and 100. A ceramic particle 36a with a Dsp of 0 means that the ceramic particle 36a is located at the midpoint position O of the perpendicular line Z0. A ceramic particle 36a with a Dsp of 100 means that the ceramic particle 36a is located at the upper or lower edge of the electrode portion 3a, which is furthest from the midpoint position O of the perpendicular line Z0. The closer Dsp is to 0, the closer the ceramic particle 36a is to the midpoint, and conversely, the closer it is to 100, the closer the ceramic particle 36a is to the upper or lower edge of the internal electrode layer 3.

[0037] In this embodiment, within the internal electrode layer 3, in the region where Dsp is 40 or less, the inner ceramic particles 36a cover an area of ​​50% or more of the total area of ​​the inner ceramic particles 36a present within the observation range of the cross-sectional photograph (for example, 12 μm × 8 μm). Preferably, in the region where Dsp is 30 or less, the inner ceramic particles 36a cover an area of ​​50% or more of the total area of ​​the inner ceramic particles 36a present within the observation range of the cross-sectional photograph (for example, 12 μm × 8 μm).

[0038] Furthermore, preferably, within the region where Dsp is 75 or less, more preferably 73 or less, the inner ceramic particles 36a are present in an area of ​​99% or more of the total area of ​​the inner ceramic particles 36a present within the observation range of the cross-sectional photograph (for example, 12 μm × 8 μm).

[0039] In order to determine whether the inner ceramic particles 36a are present in the inner electrode layer 3 within an area of ​​a predetermined proportion or more of the total area of ​​the inner ceramic particles 36a within the observation range of the cross-sectional photograph shown in Figure 2, where Dsp is below a predetermined value, the following procedure can be used, for example.

[0040] Figure 5 is a graph showing the relationship between the Dsp of each inner ceramic particle 36a shown in Figure 2 and the area cumulative frequency of the inner ceramic particles. For example, image analysis software can automatically calculate this from an image like the one shown in Figure 2. The horizontal axis shows the Dsp value, and the vertical axis shows the area cumulative frequency of the inner ceramic particles 36a within the observation range of the cross-sectional photograph. The area of ​​the inner ceramic particles 36a accumulates starting from the area of ​​inner ceramic particles 36a with a Dsp close to 0.

[0041] In the graph of Figure 5, the line connecting the circled plots represents an embodiment of the present invention, and the × marks represent a comparative example of the present invention. In the embodiment, the Dsp value at the location of 50% area cumulative frequency (Dsp50) is 25, and the Dsp value at the location of 99% area cumulative frequency (Dsp99) is 60.

[0042] In other words, as shown in the graph in Figure 5, in the embodiment, since Dsp50 is 25, it can be said that more than half (more than 50% in area) of the inner ceramic particles 36a present within the observation range of the cross-sectional photograph shown in Figure 2 are located in the region where Dsp is 40 or less, preferably 30 or less (near the center in the thickness direction). Furthermore, in the embodiment, since Dsp99 is 60, it can be said that almost all (more than 99% in area) of the inner ceramic particles 36a present within the observation range of the cross-sectional photograph shown in Figure 2 are located in the region where Dsp is 60 or less (near the center in the thickness direction).

[0043] Area cumulative frequency refers to the cumulative relative frequency (0 to 100) obtained by accumulating the area of ​​each ceramic particle 36a contained in the internal electrode layer 3 within the observation range.

[0044] Next, the manufacturing method of the multilayer ceramic capacitor 1 shown in Figures 1 and 2 will be described.

[0045] First, a ceramic green sheet containing ceramic material for forming the ceramic body 10 is prepared. Next, a conductive paste is applied to the ceramic green sheet to form a conductive pattern corresponding to the internal electrode layer 3. Since the conductive paste according to this embodiment contains, for example, the composite particles 32 shown in Figure 6, it is preferable to knead it relatively gently in order to maintain the structure of the composite particles 32, and it is preferable to knead it using a rotating and revolving agitator. Details of the composite particles 32 shown in Figure 6 will be described later.

[0046] The conductive paste can be applied by various printing methods, such as screen printing. However, since the conductive paste according to this embodiment contains composite particles 32, it is preferable to apply it by screen printing or gravure printing in order to maintain the structure of the composite particles 32.

[0047] Multiple ceramic green sheets without conductive patterns, ceramic green sheets with conductive patterns, and multiple ceramic green sheets without conductive patterns are stacked in this order, and a mother stack is manufactured by pressing them in the stacking direction.

[0048] Multiple green ceramic bodies are produced by cutting the mother layer. The mother layer can be cut by dicing or press cutting. Furthermore, the green ceramic bodies may be subjected to barrel polishing or other processes to round off edges and corners.

[0049] Before firing, the green chips are subjected to a debinding treatment. The debinding conditions are preferably a heating rate of 5 to 300°C / hour, a holding temperature of 180 to 800°C, and a holding time of 0.5 to 24 hours. The debinding atmosphere is either air or a reducing atmosphere. The heating rate during firing is not particularly limited, but is preferably 50 to 500°C / hour, more preferably 200 to 300°C / hour.

[0050] The holding temperature during firing is preferably 1200 to 1350°C, more preferably 1220 to 1300°C, and the holding time is preferably 0.5 to 8 hours, more preferably 2 to 3 hours. The firing atmosphere is preferably a reducing atmosphere, and as the atmosphere gas, for example, a humidified mixed gas of N2 and H2 can be used.

[0051] Furthermore, the oxygen partial pressure during firing should be appropriately determined according to the type of conductive material in the conductive paste, but when a base metal such as Ni or Ni alloy is used as the conductive material, the oxygen partial pressure in the firing atmosphere should be 10 -14 ~10 -10 It is preferable to use MPa. The cooling rate is preferably 50 to 500°C / hour.

[0052] After firing in a reducing atmosphere, the ceramic body 10 may be annealed. The partial pressure of oxygen in the annealing atmosphere is 10 -9 ~10 -5 The pressure should be MPa, the holding temperature during annealing should be 950-1150°C, and the holding time should be 0-20 hours. For the annealing atmosphere gas, for example, humidified N2 gas can be used.

[0053] 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. In this case, a water temperature of approximately 5 to 75°C is preferable. The debinding, firing, and annealing processes may be performed continuously or independently.

[0054] The ceramic body 10 obtained as described above is subjected to end-face polishing, for example, by barrel polishing or sandblasting, an external electrode paste is applied, and it is fired to form the external electrode 4. Then, if necessary, a coating layer is formed on the surface of the external electrode 4 by plating or the like. The external electrode paste contains not only conductive particles for external electrodes that constitute the conductive material for external electrodes after firing, but also known binders and solvents.

[0055] The multilayer ceramic capacitor 1 of this embodiment, manufactured in this manner, is mounted on a printed circuit board or the like by soldering and used in various electronic devices.

[0056] Next, the composite particle 32 will be described based on Figures 6 to 9.

[0057] As shown in Figure 6, the composite particles 32 according to this embodiment include conductive particles 34 and co-material particles 36 that are attached to the surface of the conductive particles 34 and have a smaller particle size than the conductive particles 34. The conductive particles 34 are included in the conductive paste printing pattern and become the internal electrode layer 3 shown in Figures 1 and 2 after firing. The material of the conductive particles is not particularly limited, but it is more preferably at least one selected from Ni, Ni-based alloys, Cu, Cu-based alloys, Ag, and Ag-based alloys, and even more preferably Ni or a Ni-based alloy. The conductive particles 34 may also contain various trace components such as C, S, N, and O in amounts of about 1% by mass or less.

[0058] Furthermore, in this embodiment, the conductive particles 34 may consist of multiple conductive particles 34 made of the same material, or they may be composed of a mixture of multiple conductive particles 34 made of different materials.

[0059] In this embodiment, the particle size (R) of the conductive particles 34 is preferably 20 nm to 300 nm, and more preferably 25 nm to 150 nm. In this embodiment, even if the conductive particles 34 are made relatively fine, the co-material particles 36 adhere to the surface of the conductive particles 34, which allows the sintering start temperature to be shifted to a higher temperature. Furthermore, having R within the above range makes it easier to achieve a thin internal electrode layer 3. From the above viewpoint, it is preferable that R is at least 1 / 5 of the thickness of the internal electrode layer 3.

[0060] The co-material particles 36 are the portion that becomes the ceramic particles 36a in the internal electrode layer 3 after firing in Figures 2 and 4. The material is not particularly limited, but it is preferably a material that has the effect of shifting the sintering start temperature of the internal electrode layer 3 to a higher temperature, more preferably an oxide, and even more preferably an insulating material. Specific examples of materials that have the effect of shifting the sintering start temperature of the internal electrode layer 3 to a higher temperature, are oxides, and are insulating include barium titanate, calcium barium titanate, strontium barium titanate, (Ba 1-x Ca x )(Ti 1-y Zr y ) At least one selected from O3, silicon dioxide, titanium dioxide, zirconium dioxide, and aluminum dioxide is mentioned, and it is preferably barium titanate or silicon dioxide, and barium titanate is preferred.

[0061] In this embodiment, it is preferable that the co-material particles 36 are crystalline. This allows the sintering start temperature of the internal electrode layer 3 to be shifted to a higher temperature. The crystalline nature can be confirmed, for example, by scanning transmission electron microscopy (STEM) or X-ray diffraction (XRD).

[0062] Furthermore, the co-material particles 36 in this embodiment are smaller than the conductive particles 34. The particle size (r) of the co-material particles 36 is 2 nm to 30 nm, preferably 5 nm to 20 nm. By including r within this range, the dispersion of the co-material particles becomes easier.

[0063] In this embodiment, when the particle size of the conductive particle 34 is represented as R and the particle size of the co-material particle 36 attached to the conductive particle 34 is represented as r, (r / R) is preferably 0.01 to 0.17, and more preferably 0.03 to 0.15. When r / R is within the above range, the co-material particle 36 is less likely to detach from the conductive particle 34.

[0064] Furthermore, in this embodiment, the co-material particles 36 may consist of multiple co-material particles 36 of the same material, or a mixture of multiple co-material particles 36 of different materials may be used.

[0065] If the co-material particles 36 are composed of two or more different materials, the average particle size of the co-material particles 36 composed of one material may be different from the average particle size of the co-material particles 36 composed of another material.

[0066] The particle sizes of the conductive particles 34 and co-material particles 36, as well as the coverage rate of the co-material particles 36 on the conductive particles 34, according to this embodiment, are as follows.

[0067] The liquid containing the composite particles 32 is dropped onto the stage of a scanning electron microscope (SEM) or STEM and air-dried. Next, SEM images are taken. A schematic diagram of the SEM image is shown in Figure 7. The field of view of the SEM image is not particularly limited, but it should be approximately (R × 8) × (R × 6) when the average particle size of the conductive particles 34 is represented as R.

[0068] Next, "conductive particles 34 with identifiable outlines" are selected from SEM images, etc. Figure 8 shows the outlines of "conductive particles 34 with identifiable outlines" in Figure 7 with thick lines, and also shows the outlines of "common material particles 36 with identifiable outlines" attached to "conductive particles 34 with identifiable outlines" with thick lines. Note that "conductive particles 34 with identifiable outlines" means conductive particles 34 whose entire outline is included in the SEM image, etc., and which are located at the forefront in the SEM image, etc. Therefore, if even a part is missing, that conductive particle 34 is not considered a "conductive particle 34 with identifiable outlines". Also, if even a part is located behind (on the back) of other conductive particles 34, that conductive particle 34 is not considered a "conductive particle 34 with identifiable outlines".

[0069] For the "conductive particles 34 with identifiable outlines" and the "common material particles 36 with identifiable outlines" attached to the "conductive particles 34 with identifiable outlines" confirmed by the above method, the equivalent circle diameter is determined for each, and the equivalent circle diameter is used as the particle size to determine the particle size (R) of the conductive particles 34 and the average particle size (r) of the particles 36, respectively.

[0070] Furthermore, as shown in Figure 9, the centroid G is determined for each of the "conductive particles 34 whose outlines can be confirmed," and a circle with a radius of "0.25 × particle size (Ra) of the conductive particle" is drawn from the centroid G, and this circle is defined as a virtual circle 38. Note that "particle size Ra" refers to the particle size of each conductive particle 34, not the average particle size. The coverage rate is defined as the sum of the areas of the common material particles 36 contained in the virtual circle 38 relative to the area of ​​the virtual circle 38. The coverage rate is determined for all of the "conductive particles 34 whose outlines can be confirmed" shown in Figures 7 and 8, and the average value is defined as the average coverage rate.

[0071] In this embodiment, the average coverage rate of the co-material particles 36 on the conductive particles 34 is preferably 3% to 50%, and more preferably 5% to 30%. Furthermore, the variation in coverage rate, indicated by the standard deviation of the coverage rate, is preferably 0% to 20%, and more preferably 0% to 5%. In this embodiment, by attaching the co-material particles 36 to the conductive particles 34 by electrostatic adsorption, as described later, the aggregation of the co-material particles 36 can be suppressed, and thus the variation in coverage rate can be kept low.

[0072] In this embodiment, the ratio of composite particles 32 with 0% coverage to the number of observed composite particles 32, i.e., the ratio of composite particles 32 with 0% coverage, is preferably 60% or less, and more preferably 10% or less.

[0073] Furthermore, in this embodiment, for example, when r / R = approximately 0.07 to 0.09, it is preferable that the number of co-material particles 36 included in the virtual circle 38 be 0 to 20, and more preferably 1 to 15. Note that "co-material particles 36 included in the virtual circle 38" does not include co-material particles 36 that are partially missing.

[0074] In this embodiment, it is preferable that the number of aggregates of co-material particles 36 in a field of view of (R×80)×(R×60) be 3 or less, more preferably 1 or less, and even more preferably 0. In this embodiment, it is preferable that the content of co-material particles 36 relative to conductive particles 34 be 1 vol% or more and 23 vol% or less, and more preferably 2 vol% or more and 15 vol% or less.

[0075] Next, a method for producing the composite particles 32 shown in Figure 6 will be described.

[0076] First, in this embodiment, conductive particles 34 and co-material particles 36 are prepared, and the composite particles 32 shown in Figure 6 are produced by attaching the co-material particles 36 to the surface of the conductive particles 34. The method for attaching the co-material particles 36 to the surface of the conductive particles 34 is not particularly limited. For example, the co-material particles 36 may be attached to the surface of the conductive particles 34 by electrostatic adsorption, or by a mechanochemical method, or by a method of depositing the co-material particles 36 on the surface of the conductive particles 34 through synthesis, or by attaching the co-material particles 36 to the surface of the conductive particles 34 via an organic material such as a resin.

[0077] In this embodiment, it is preferable to attach the co-material particles 36 to the surface of the conductive particles 34 by electrostatic adsorption. This is because, in the case of electrostatic adsorption, it is possible to attach the co-material particles 36 to the surface of the conductive particles 34 with low energy. Furthermore, in the case of electrostatic adsorption, the co-material particles 36 can be adsorbed onto the conductive particles 34 in a near monodisperse state.

[0078] Furthermore, in the case of electrostatic adsorption, separately synthesized "highly crystalline materials," "highly heat-resistant materials," and / or "nearly spherical materials" can be used as co-material particles 36, thereby maximizing the effect of the co-material particles 36 as a co-material. Note that the closer the co-material particles 36 are to spherical, the smaller the specific surface area (a perfect sphere is the smallest), and the lower the surface free energy tends to result in a higher sintering start temperature.

[0079] Furthermore, in the case of electrostatic adsorption, aggregation of the co-material particles 36 can be reduced. Aggregation of co-material particles 36 leads to a decrease in the number of co-material particles 36 that function effectively as a co-material, which can be the starting point for electrode interruption.

[0080] Furthermore, since the thickness of electrostatic adsorption can be changed by changing the particle size of the co-material particles 36, it is easy to control the adsorption thickness of the co-material (co-material particles 36) on the surface of the conductive particles 34. In addition, in the case of electrostatic adsorption, since the conductive particles 34 and the co-material particles 36 are charged with opposite charges before adsorption, there is also the advantage that it is easy to control the amount of co-material particles 36 that adhere to the conductive particles 34.

[0081] For the reasons stated above, by adhering the co-material particles 36 to the surface of the conductive particles 34 by electrostatic adsorption, the effect of shifting the sintering start temperature of the composite particles 32 to a higher temperature can be further enhanced.

[0082] The oxide nanoparticles used as the co-material particles 36 have hydroxyl groups on their outermost surface, and therefore are generally highly hydrophilic and disperse well in water and highly polar solvents, such as alcohols and glycols. Depending on the manufacturing and dispersion methods, oxide nanoparticles often have a negative surface charge and can be used in compounding. A small amount of additive may be used to stabilize the dispersion.

[0083] Nickel powder used as conductive particles 34 has a very weak positive or negative charge, depending on the manufacturing method. By using polymer electrolytes such as polydiallyldimethylammonium chloride (PDDA) and polyethyleneimine (PEI), it can be converted to a strong positive charge, allowing it to be compounded with negatively charged oxide nanoparticles (composite material particles 36).

[0084] Furthermore, when using BaTiO3 as the co-material particle 36, the composite is formed, for example, by the following method. First, positively charged Ni particles (conductive particles 34) are added to an organic solvent to prepare a "dispersion containing positively charged Ni particles".

[0085] Furthermore, a dispersion containing BaTiO3 with a negatively charged surface is also prepared. The reason for using an organic solvent in this way is that if water is used as the solvent, the surface ions of BaTiO3 will dissolve into the water. Alcohols, glycols, ketones, etc., can be used as the solvent for the BaTiO3 solution.

[0086] A dispersion containing positively charged Ni particles and a dispersion containing negatively charged BaTiO3 particles are mixed, and the BaTiO3 particles are adsorbed onto the Ni particles by electrostatic adsorption to obtain composite particles 32.

[0087] The internal electrode layer 3 of the multilayer ceramic capacitor 1 according to this embodiment can be formed, for example, by a conductive paste containing composite particles 32. Since the composite particles 32 are fine, the requirement for thinning the multilayer ceramic capacitor 1 can be met.

[0088] Furthermore, the co-material particles 36 have the effect of shifting the sintering start temperature of the composite particles 32 to a higher temperature, and the composite particles 32 have a configuration in which the co-material particles 36 are attached to the surface of the conductive particles 34.According to the conductive paste having composite particles 32 according to this embodiment, the sintering start temperature of the composite particles 32 can be efficiently shifted to a higher temperature, bringing it closer to the sintering start temperature of the ceramic layer 2.As a result, cracks in the ceramic layer 2 caused by differences in thermal shrinkage behavior between the internal electrode layer 3 and the ceramic layer 2 can be prevented, as well as electrode breaks in the internal electrode layer 3 can be prevented.

[0089] Furthermore, as described above, the composite particles 32 according to this embodiment can efficiently shift the sintering start temperature of the internal electrode layer 3 to a higher temperature, thus reducing the amount of co-material compared to conventional conductive pastes. This reduces the influence of the co-material on the ceramic layer 2.

[0090] Furthermore, by using the composite particles 32 according to this embodiment, for example, as shown in Figure 2, the ceramic particles 36a made of the same material particles 36 after firing are often located near the center in the thickness direction within the internal electrode layer 3, and the area ratio of the ceramic particles 36a occupying the region where Dsp is less than or equal to a predetermined value becomes greater than or equal to a predetermined value.

[0091] In this embodiment, more than half (more than 50% in area) of the inner ceramic particles 36a within the observation range of the cross-sectional photograph shown in Figure 2 are located in a region where Dsp is 40 or less, preferably 30 or less (near the center in the thickness direction). A multilayer ceramic capacitor 1 having an internal electrode layer 3 with such a configuration can simultaneously satisfy thinning of the internal electrode layer 3 and high continuity. Furthermore, thinning of the ceramic layer 2 (for example, a dielectric layer) laminated between the pair of internal electrode layers 3 is achieved simultaneously with thinning of the internal electrode layer 3, and variations in the thickness of these layers are also reduced.

[0092] Furthermore, in this embodiment, almost all (more than 99% by area) of the inner ceramic particles 36a within the observation range of the cross-sectional photograph shown in Figure 2 are located in a region where Dsp is 75 or less, preferably 73 or less. In a multilayer ceramic capacitor 1 having an internal electrode layer 3 with such a configuration, thinning of the internal electrode layer 3 and high continuity can be satisfied simultaneously. In addition, thinning of the ceramic layer 2 (for example, the dielectric layer) which is laminated sandwiched between the pair of internal electrode layers 3 is achieved at the same time as thinning of the internal electrode layer 3, and variations in the thickness of these layers are also reduced.

[0093] Furthermore, the ratio of the total area of ​​the inner ceramic particles 36a to the total area of ​​the internal electrode layers within the observation range is preferably 2.5% or less, and more preferably 2% or less. With a multilayer ceramic capacitor 1 having an internal electrode layer 3 with such a configuration, the coverage rate of the internal electrode layer 3 over the ceramic layer 2 is improved, and the continuity of the internal electrode layer 3 is further improved.

[0094] Furthermore, in this embodiment, the maximum particle size of the inner ceramic particles 36a present within the observation range is 69 nm or less, more preferably 63 nm or less. The fact that the maximum particle size of the inner ceramic particles 36a is below a predetermined value indicates that aggregation of fine-particle-sized co-material particles (for example, the co-material particles 36 shown in Figure 6) in the paste film for the internal electrode layer is suppressed. As a result of suppressing the aggregation of co-material particles 36 and firing the paste film for the internal electrode layer, abnormal particle growth of the conductive particles 34 shown in Figure 6 in the paste film is suppressed, contributing to the thinning and uniformity of the thickness of the internal electrode layer 3 shown in Figure 2, and further improving the continuity of the internal electrode layer 3.

[0095] Furthermore, for example, the area of ​​the internal electrode layer 3 within the observation range of the cross-sectional photograph shown in Figure 2 is 50 μm². 2 The number of inner ceramic particles 36a per layer is 185 or less, more preferably 170 or less, and for example, within the range of 55 to 166. By controlling the number of inner ceramic particles 36a, it contributes to thinning the inner electrode layer 3, improves the coverage rate of the inner electrode layer 3 over the ceramic layer 2, and further improves the continuity of the inner electrode layer 3.

[0096] It should be noted that the present invention is not limited to the embodiments described above, and can be modified in various ways within the scope of the present invention.

[0097] For example, the electronic component of this embodiment is not limited to multilayer ceramic capacitors, but can be applied to other electronic components as well. Other electronic components include all electronic components in which ceramic layers are stacked via internal electrode layers, such as bandpass filters, inductors, multilayer three-terminal filters, piezoelectric elements, PTC thermistors, NTC thermistors, and varistors.

[0098] Furthermore, the internal electrode layer 3 of this embodiment may be obtained by firing a combination of conductive particles with a structure other than the composite particles 32 and a common material. The material of the conductive particles is not particularly limited, but Ni, Ni-based alloys, Cu, or Cu-based alloys can be used.

[0099] Furthermore, the internal electrode layer 3 may also contain ceramic particles 36a that do not originate from the co-material particles 36. The ceramic particles 36a that do not originate from the co-material particles 36 may originate from particles that are included in the conductive paste in a different form, rather than as part of the composite particles 32. The material of the particles that do not originate from the co-material particles 36 is not particularly limited, but it is preferable that they be the same material as any of the components constituting the ceramic layer 2 in order to reduce their influence on the composition of the ceramic layer 2.

[0100] Furthermore, when forming the external electrode 4, instead of forming it by firing the paste, the external electrode 4 may be formed using a resin containing composite particles 32. In other words, the external electrode 4 may be a resin electrode containing composite particles 32. [Examples]

[0101] The present invention will be described below based on more detailed examples, but the present invention is not limited to these examples.

[0102] Example 1 A 100nm nickel powder dispersion (initial zeta potential of +8mV) was prepared using D50. A polymer electrolyte polyethyleneimine (PEI) was added at a concentration of 400ppm relative to the weight of the nickel and dissolved in the ethanol. The zeta potential of the nickel after dissolution (measured using a Malvern Zetasizer Nano) was measured at +30mV, confirming that the nickel surface acquired a negative potential due to the PEI.

[0103] Next, an ethanol dispersion of barium titanate (co-material particles) as oxide nanoparticles (D50: 10 nm) was prepared. The zeta potential of the barium titanate dispersion was measured using the same apparatus as above and showed -20 mV. This confirmed that the zeta potential of the nickel surface is positive, and the zeta potential of the untreated barium titanate surface is negative.

[0104] Next, the two dispersions described above were mixed and dispersed in an ultrasonic homogenizer for 10 minutes, after which they were dried at 100°C for 1 hour. The dried composite powder was mixed with a solvent (terpineol) and a binder (ethylcellulose) to complete a paste containing the composite particles. At this time, the weight of barium titanate was 5 parts by weight (5 PHP) per 100 parts by weight of nickel particles (conductive particles). The volume percentage of barium titanate was 6.9 vol%.

[0105] The conductive paste obtained in this manner contained 45 parts by mass of composite particles, 3 parts by mass of ethyl cellulose, and 52 parts by mass of solvent, when the total paste volume was 100 parts by mass.

[0106] Furthermore, a different composite particle from the one contained in the conductive base was added to ethanol at a ratio of 0.5% by mass and mixed for 1 minute using a vortex mixer. The mixture was allowed to stand for 1 to 2 hours to allow the composite particle to settle. The supernatant was removed by decantation, and ethanol was added again and mixed. The resulting solution containing the composite particle was dropped onto an SEM stage, air-dried, and observed by SEM. The coverage rate of the composite particle on the conductive particle was measured. The results are shown in Table 1. The average coverage rate of the composite particle was 30%.

[0107] Next, a conductive paste was applied to a ceramic green sheet mainly composed of BaTiO3 to form a conductive pattern corresponding to the internal electrode layer 3. A mother laminate was fabricated by stacking multiple ceramic green sheets without conductive patterns, a ceramic green sheet with conductive patterns, and multiple ceramic green sheets without conductive patterns in this order and pressing them in the stacking direction.

[0108] Multiple pre-firing ceramic bodies (green chips) were prepared by cutting the mother laminate. Next, the obtained green chips were subjected to binder removal, firing, and annealing under the following conditions to obtain laminated ceramic fired bodies (ceramic bodies).

[0109] The debinder removal conditions were: heating rate: 25°C / hour, holding temperature: 500°C, holding time: 8 hours, and atmosphere: humidified N2+H2 mixed gas.

[0110] The firing conditions were: heating rate: 200°C / hour, holding temperature: 1200~1350°C, holding time: 1 hour. Cooling rate: 200°C / hour. The atmospheric gas was a humidified N2+H2 mixed gas with an oxygen partial pressure of 10. -12 I adjusted it to be in MPa.

[0111] The annealing conditions were: heating rate: 200°C / hour, holding temperature: 1000°C, holding time: 2 hours, cooling rate: 200°C / hour, ambient gas: humidified N2 gas (oxygen partial pressure: 10%). -7 (MPa)

[0112] Furthermore, a wetter was used to humidify the atmospheric gas during firing and annealing.

[0113] Next, the end faces of the obtained ceramic substrates were polished by sandblasting, and then Cu was applied as an external electrode to obtain a sample of a multilayer ceramic capacitor shown in Figure 1. The size of the obtained capacitor sample was 1.0 mm × 0.5 mm × 0.5 mm.

[0114] The obtained capacitor sample was cut in a cross-section parallel to the Z-axis, and the cross-section was observed using SEM. The observation range of the cross-section was 8 μm × 12 μm or larger, and was the range in which 10 or more internal electrode layers 3 could be observed. For example, by image processing the cross-section as shown in Figure 2, the Dsp of at least 50 inner ceramic particles 36a located inside each inner electrode layer 3 was measured using the method shown in Figure 4 above. Furthermore, the area of ​​each inner ceramic particle 36a for which the Dsp was measured was measured in relation to the Dsp value and cumulatively added up to determine the relationship between the ratio (cumulative area frequency) to the total area of ​​all observed inner ceramic particles 36a and the Dsp. The data of this relationship is shown graphically by the line connecting the circles in Figure 5.

[0115] Dsp50 and Dsp99 were determined from the graph shown by the lines connecting the dots in Figure 5, or from the raw data of that graph. The results are shown in Table 1. As shown in Table 1, in Example 1, Dsp50 was 25 and Dsp99 was 60. Note that Dsp50 is the value of Dsp at the location where the cumulative area frequency is 50%, as mentioned above, and Dsp99 is the value of Dsp at the location where the cumulative area frequency is 99%.

[0116] Furthermore, by image processing of a cross-section, such as the one shown in Figure 2, the largest particle size among at least 50 inner ceramic particles 36a located inside each inner electrode layer 3 was detected, and its area was determined. The results are shown in Table 1. Also, for example, the area of ​​the inner electrode layer 3 within the observation range of the cross-sectional photograph shown in Figure 2 is 50 μm². 2 The number of inner ceramic particles 36a per unit area was determined. The results are shown in the "Number of Ceramic Particles" column of Table 1.

[0117] Furthermore, within the observation range of the cross-section shown in Figure 2, the average thickness and variation σ of the dielectric layer 2, and the average thickness and variation σ of the internal electrode layer 3 were measured by image processing. The results are shown in Table 2.

[0118] Furthermore, the electrode coverage rate, the number of electrode divisions, and the area ratio of ceramic particles of the internal electrode layer 2 were measured and determined from cross-sectional observations as shown in Figure 2. The electrode coverage rate was determined by the method shown in Figure 3, as described above. The number of electrode divisions was calculated, for example, by dividing the total number of observed electrode portions 3a by the total number of internal electrode layers 3 in a cross-sectional SEM image where 10 or more internal electrode layers 3 are observed.

[0119] The ceramic particle area ratio was determined by calculating the ratio of the total area occupied by ceramic particles 36a to the total area occupied by electrode portion 3a in a cross-sectional SEM image where 10 or more internal electrode layers are observed, and this was defined as the area ratio. These results are shown in Table 2.

[0120] Examples 2-6 Capacitor samples were manufactured in the same manner as in Example 1, except that the weight of barium titanate per 100 parts by weight of nickel particles in the conductive paste was 7 parts by weight (7 PHP), 9 PHP, 11 PHP, 13 PHP, and 15 PHP. The co-material coverage rate of the composite particles used in each of Examples 2 to 6 was measured in the same manner as in Example 1. The results are shown in Table 1.

[0121] Furthermore, in the same manner as in Example 1, the Dsp50, Dsp99, maximum diameter of ceramic particles, number of ceramic particles, average dielectric thickness and its variation σ, average thickness of the internal electrode layer (electrode thickness) and its variation σ, electrode coverage, number of electrode divisions, and ceramic particle area ratio were determined for each capacitor sample according to the example. These results are shown in Table 1 or Table 2.

[0122] Comparative Example 1 A capacitor sample was manufactured in the same manner as in Example 1, except that nickel particles (conductive particles) and barium titanate (common material particles) were prepared separately without creating composite particles, and these were mixed and dispersed with a solvent (terpineol) and a binder (ethylcellulose) to prepare a conductive paste. The co-material coverage rate of the co-material particles on the surface of the conductive particles in the conductive paste used in Comparative Example 1 was measured in the same manner as in Example 1. The results are shown in Table 1.

[0123] Furthermore, in the same manner as in Example 1, the Dsp50, Dsp99, maximum diameter of ceramic particles, number of ceramic particles, average dielectric thickness and its variation σ, average thickness of the internal electrode layer (electrode thickness) and its variation σ, electrode coverage, number of electrode divisions, and ceramic particle area ratio of the capacitor sample related to Comparative Example 1 were determined. These results are shown in Table 1 or Table 2.

[0124] Comparative Examples 2-6 Capacitor samples were manufactured in the same manner as in Comparative Example 1, except that composite particles were not prepared, and the weight of barium titanate per 100 parts by weight of nickel particles in the conductive paste was set to 7 parts by weight (7 PHP), 9 PHP, 11 PHP, 13 PHP, and 15 PHP. The co-material coverage rate of the co-material particles on the surface of the conductive particles in the conductive paste used in each Comparative Example 2 to 6 was measured in the same manner as in Comparative Example 1. The results are shown in Table 1.

[0125] Furthermore, in the same manner as in Comparative Example 1, the Dsp50, Dsp99, maximum diameter of ceramic particles, number of ceramic particles, average dielectric thickness and its variation σ, average thickness of the internal electrode layer (electrode thickness) and its variation σ, electrode coverage, number of electrode divisions, and ceramic particle area ratio were determined for each comparative example capacitor sample. These results are shown in Table 1 or Table 2.

[0126] Rating 1 Compared to Comparative Examples 1 to 6, Examples 1 to 6 demonstrated superior electrode continuity, smaller electrode thickness variations σ in the internal electrode layer and dielectric thickness variations σ in the dielectric layer, and thus superior thinning capabilities. Furthermore, the results shown in Tables 1 and 2 confirm that when Dsp50 is 40 or less, preferably 30 or less, the electrode coverage improves, the number of electrode divisions decreases, electrode continuity improves, thickness variation σ decreases, and thinning capabilities are excellent. Additionally, when Dsp99 is 80 or less, preferably 73 or less, the electrode coverage improves, the number of electrode divisions decreases, electrode continuity improves, thickness variation σ decreases, and thinning capabilities are excellent.

[0127] Furthermore, it was confirmed that when the maximum particle size of the inner ceramic particles is 69 nm or less, and more preferably 63 nm or less, the electrode continuity of the internal electrode layer is excellent, and the variation in electrode thickness σ of the internal electrode layer and the variation in dielectric thickness σ of the dielectric layer are small.

[0128] Furthermore, the area of ​​the internal electrode layer is 50 μm². 2It was confirmed that when the number of inner ceramic particles per unit area is 185 or less, more preferably 170 or less, and for example within the range of 55 to 166, the electrode continuity of the internal electrode layer is excellent, and the variation in electrode thickness σ of the internal electrode layer and the variation in dielectric thickness σ of the dielectric layer are small.

[0129] Furthermore, it was confirmed that when the ratio of the total area of ​​the inner ceramic particles is 2.5% or less, more preferably 2% or less, the electrode continuity of the internal electrode layer is excellent, and the electrode thickness variation σ of the internal electrode layer and the dielectric thickness variation σ of the dielectric layer are small.

[0130] [Table 1]

[0131] [Table 2]

[0132] 1… Multilayer ceramic capacitor 2… Ceramic layer (dielectric layer) 3… Internal electrode layer 3a… Electrode part 3b… Electrode discontinuity part 32… Composite particles 34… Conductive particles 36… Common material particles 36a... Inner ceramic particles 38… Virtual Yen 4... External electrode 10… Ceramic body

Claims

1. A multilayer ceramic electronic component having alternatingly stacked ceramic layers and an internal electrode layer, Within the observation range of the cross-section that intersects with the aforementioned internal electrode layer, The internal electrode layer contains a plurality of internal ceramic particles inside, Dsp is an index that indicates the relative position of the inner ceramic particles within the inner electrode layer with respect to the central position in the thickness direction of the inner electrode layer, corresponding to the distance from the central position to the edge position, using a number from 0 to 100. A multilayer ceramic electronic component in which, within the internal electrode layer, the internal ceramic particles are present in a region where Dsp is 40 or less, and the area of ​​the internal ceramic particles within the observation range is 50% or more of the total area of ​​the internal ceramic particles present.

2. A multilayer ceramic electronic component having alternatingly stacked ceramic layers and an internal electrode layer, Within the observation range of the cross-section that intersects with the aforementioned internal electrode layer, The internal electrode layer contains a plurality of internal ceramic particles inside, Dsp is an index that indicates the relative position of the inner ceramic particles within the inner electrode layer with respect to the central position in the thickness direction of the inner electrode layer, corresponding to the distance from the central position to the edge position, using a number from 0 to 100. A multilayer ceramic electronic component in which, within the internal electrode layer, the internal ceramic particles are present in a region where Dsp is 75 or less, and the area of ​​the internal ceramic particles within the observation range is 99% or more of the total area of ​​the internal ceramic particles present.

3. The multilayer ceramic electronic component according to claim 1 or 2, wherein the ratio of the total area of ​​the inner ceramic particles to the total area of ​​the inner electrode layers within the observation range is 2.5% or less.

4. The multilayer ceramic electronic component according to claim 1 or 2, wherein the maximum particle size of the inner ceramic particles present within the observation range is 69 nm or less.

5. Area of ​​the internal electrode layer within the observation range: 50 μm 2 The multilayer ceramic electronic component according to claim 1 or 2, wherein the number of inner ceramic particles per unit area is 185 or less.

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