Multilayer ceramic electronic component and dielectric ceramic composition

Abstract

The present invention provides a laminated ceramic electronic component and a dielectric ceramic composition capable of ensuring reliability. The laminated ceramic electronic component has: a dielectric layer (11) having a plurality of dielectric particles (30) containing a first rare earth element and a second rare earth element, the first rare earth element being at least one element selected from the group consisting of lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, and gadolinium, the second rare earth element being at least one element selected from the group consisting of yttrium, scandium, holmium, erbium, thulium, ytterbium, and lutetium, the atomic number ratio of the first rare earth element to the second rare earth element being 65:35 to 35:65, and a segregation phase (40) having silicon oxide as a main component at a triple point of grain boundaries of the plurality of dielectric particles (30); a plurality of internal electrode layers (12) facing each other across the dielectric layer (11); and external electrodes (20a, 20b) electrically connected to the plurality of internal electrode layers (12).

Description

Technical Field

[0001] This invention relates to laminated ceramic electronic components and dielectric ceramic compositions. Background Technology

[0002] In recent years, the use of multilayer ceramic electronic components, such as multilayer ceramic capacitors, has been increasing, particularly in applications requiring operation at high voltages up to 100V, such as large-scale data centers and automotive power systems. Therefore, the materials used in these multilayer ceramic electronic components must also ensure reliability under high voltage conditions.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2024-50136 Summary of the Invention

[0006] The technical problem that the invention aims to solve

[0007] For example, one method could be to introduce oxide ions (O2) into the crystal lattice, which are considered a major factor determining the reliability of multilayer ceramic electronic components under high voltage. 2- The concentration of defects is reduced as much as possible after sintering, so that the rate at which defects accumulate at the electrode interface when voltage is applied is slowed down, thereby ensuring reliability.

[0008] When using a metal cheaper than hydrogen, such as nickel, as the internal electrode layer, the firing process must be carried out in a reducing atmosphere to prevent oxidation of the electrode metal. However, for example, in the case of a multilayer ceramic electronic component with barium titanate as the main component, which is a ferroelectric material, to ensure high capacitance, titanium ions (Ti) in a reducing atmosphere are required. 4+ It will be partially reduced to Ti 3+ To maintain the overall electrical neutrality of the oxide, oxide ion defects are generated. Therefore, there is a limit to reducing the concentration of oxide ion defects after sintering. It can be assumed that oxide ion defects migrate due to the internal electric field when a voltage is applied, eventually accumulating at the interface between the internal electrode layer and the dielectric layer. When this accumulation further develops, the interface resistance disappears, and the overall electrical reliability of the stacked ceramic electronic component disappears.

[0009] The present invention was made in view of the above-mentioned technical problems, and its object is to provide a laminated ceramic electronic component and a dielectric ceramic composition that can ensure reliability.

[0010] Means for solving technical problems

[0011] The stacked ceramic electronic component of the present invention comprises: a dielectric layer having a plurality of dielectric particles comprising a first rare earth element and a second rare earth element, wherein the first rare earth element is at least one element selected from lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, and gadolinium, and the second rare earth element is at least one element selected from yttrium, scandium, holmium, erbium, thulium, ytterbium, and lutetium, wherein the atomic ratio of the first rare earth element to the second rare earth element is 65:35 to 35:65, and a segregated phase mainly composed of silicon oxide is present at the grain boundary three points of the plurality of dielectric particles; a plurality of internal electrode layers facing each other across the dielectric layer; and an external electrode electrically connected to the plurality of internal electrode layers.

[0012] In the above-mentioned stacked ceramic electronic components, the segregated phase may be adjacent to more than 50% of the dielectric particles in the plurality of dielectric particles.

[0013] In the above-mentioned stacked ceramic electronic components, the average diameter of the segregated phase may be 10 nm or more.

[0014] In the above-mentioned stacked ceramic electronic components, the content of the first rare earth element and the second rare earth element in the dielectric particles may be more than 1.5 mol% and less than 6.0 mol%.

[0015] In the aforementioned stacked ceramic electronic components, the first rare earth element may be europium, and the second rare earth element may be yttrium.

[0016] In the above-mentioned stacked ceramic electronic components, the dielectric particles may be mainly composed of ceramic materials with a perovskite structure.

[0017] In the above-mentioned stacked ceramic electronic components, the ceramic material may be barium titanate.

[0018] The ceramic composition of the present invention comprises a plurality of dielectric particles containing a first rare earth element and a second rare earth element. The first rare earth element is at least one element selected from lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, and gadolinium. The second rare earth element is at least one element selected from yttrium, scandium, holmium, erbium, thulium, ytterbium, and lutetium. The atomic ratio of the first rare earth element to the second rare earth element is 65:35 to 35:65. The plurality of dielectric particles have a segregated phase with silicon oxide as the main component at the grain boundary three points.

[0019] Invention Effects

[0020] Using this invention, it is possible to provide laminated ceramic electronic components and dielectric ceramic compositions that can ensure reliability. Attached Figure Description

[0021] Figure 1This is a three-dimensional view of a partial cross-section of a multilayer ceramic capacitor.

[0022] Figure 2 yes Figure 1 AA-line cross-section diagram.

[0023] Figure 3 yes Figure 1 BB line cross-section diagram.

[0024] Figure 4 (a) and (b) are magnified views of the vicinity of the external electrode.

[0025] Figure 5 This is a schematic cross-sectional view of the dielectric layer.

[0026] Figure 6 It is an enlarged cross-sectional view of the periphery of the dielectric particles.

[0027] Figure 7 This is a flowchart illustrating a method for manufacturing multilayer ceramic capacitors.

[0028] Figure 8 (a) and (b) are illustrations of the printing process.

[0029] Figure 9 This is a diagram illustrating the crimping process.

[0030] Figure 10 This is a diagram obtained by tracking the BSE image of the sample from Example 1.

[0031] Figure 11 This is a diagram obtained by tracking the BSE image of the sample in Comparative Example 1.

[0032] Figure 12 This is a diagram obtained by tracking the BSE image of the sample in Comparative Example 2.

[0033] Figure 13 This is a graph showing the results of the reliability test in Example 1.

[0034] Figure 14 This is a graph showing the results of the reliability test for Comparative Example 1.

[0035] Figure 15 This is a graph showing the results of the reliability test for Comparative Example 2.

[0036] Explanation of reference numerals in the attached figures

[0037] 10 Main body, 11 Dielectric layer, 12 Internal electrode layer, 13 Cover layer, 14 Capacitor section, 15 End edge, 16 Side edge, 20a, 20b External electrodes, 30 Dielectric particles, 40 Segregated phase, 51 Dielectric green sheet, 52 Internal electrode pattern, 53 Reverse pattern, 54 Cover sheet, 100 Multilayer ceramic capacitor. Detailed Implementation

[0038] The embodiments will now be described with reference to the accompanying drawings.

[0039] (Implementation Method)

[0040] Figure 1 This is a partial cross-sectional perspective view of the stacked ceramic capacitor 100 according to the embodiment. Figure 2 yes Figure 1 AA-line cross-section diagram. Figure 3 yes Figure 1 The BB line cross-sectional view. (See diagram below.) Figures 1-3 As illustrated, the multilayer ceramic capacitor 100 includes: a body 10 having a generally cuboid shape; and external electrodes 20a and 20b disposed on any two opposite end faces of the body 10. Furthermore, the two surfaces of the body 10 other than the two end faces, excluding the upper and lower surfaces in the stacking direction, are referred to as side faces. The external electrodes 20a and 20b extend along the upper surface, lower surface, and two side faces of the body 10 in the stacking direction. However, the external electrodes 20a and 20b are spaced apart from each other.

[0041] In addition, Figures 1-3 In this diagram, the Z-axis direction (first direction) is the stacking direction and the direction in which the internal electrode layers are opposite to each other. The X-axis direction (second direction) is the length direction of the main body 10, the direction in which the two end faces of the main body 10 are opposite to each other, and the direction in which the external electrodes 20a and 20b are opposite to each other. The Y-axis direction (third direction) is the width direction of the internal electrode layers and the direction in which the two sides of the main body 10 other than the two end faces are opposite to each other. The X-axis, Y-axis, and Z-axis directions are orthogonal to each other.

[0042] The main body 10 has a structure in which a dielectric layer 11, comprising a ceramic material (dielectric ceramic composition) that functions as a dielectric, and an internal electrode layer 12 are alternately stacked. The end edges of each internal electrode layer 12 are alternately exposed on the end face of the main body 10 where an external electrode 20a is disposed and the end face where an external electrode 20b is disposed. Thus, each internal electrode layer 12 is alternately connected to the external electrode 20a and the external electrode 20b. In the stack of dielectric layer 11 and internal electrode layer 12, the internal electrode layer 12 is disposed as the outermost layer in the stacking direction, and the upper and lower surfaces of this stack are covered by a capping layer 13. The capping layer 13 is primarily composed of a ceramic material. For example, the composition of the capping layer 13 can be the same as or different from that of the dielectric layer 11. Furthermore, it is not limited to any particular type of stack as long as the internal electrode layer 12 is exposed on two different faces and connected to different external electrodes. Figures 1-3 The structure.

[0043] The dimensions of the multilayer ceramic capacitor 100 are, for example, a length of 0.25 mm, a width of 0.125 mm, and a height of 0.125 mm; or a length of 0.4 mm, a width of 0.2 mm, and a height of 0.2 mm; or a length of 0.6 mm, a width of 0.3 mm, and a height of 0.3 mm; or a length of 1.0 mm, a width of 0.5 mm, and a height of 0.5 mm; or a length of 3.2 mm, a width of 1.6 mm, and a height of 1.6 mm; or a length of 4.5 mm, a width of 3.2 mm, and a height of 2.5 mm, but are not limited to these dimensions.

[0044] The internal electrode layer 12 is primarily composed of base metals such as nickel (Ni), copper (Cu), and tin (Sn), or alloys containing them. Alternatively, noble metals such as platinum (Pt), palladium (Pd), silver (Ag), and gold (Au), or alloys containing them, can also be used as the internal electrode layer 12. The thickness of the internal electrode layer 12 is, for example, 5.0 μm or less, 3.0 μm or less, or 1.0 μm or less. The thickness of the internal electrode layer 12 can be measured by observing the cross-section of the stacked ceramic capacitor 100 using a SEM (scanning electron microscope), measuring the thickness at 10 points for each of the 10 different internal electrode layers 12, and deriving the average value of all measured points.

[0045] The dielectric layer 11 is primarily composed of a ceramic material having a perovskite structure represented by the general formula ABO3. Furthermore, this perovskite structure contains ABO3, deviating from its stoichiometric composition. 3-α For example, as this ceramic material, materials selected from barium titanate (BaTiO3), calcium zirconate (CaZrO3), calcium titanate (CaTiO3), strontium titanate (SrTiO3), magnesium titanate (MgTiO3), and Ba, which form a perovskite structure, can be used. 1-x-y Ca x Sry Ti 1-z Zr z O3 (0≤x≤1, 0≤y≤1, 0≤z≤1), etc. Ba 1-x- y Ca x Sr y Ti 1-z Zr z O3 can be barium strontium titanate, barium calcium titanate, barium zirconate, barium zirconate titanate, calcium zirconate titanate, or barium calcium zirconate titanate. For example, the dielectric layer 11 contains more than 90 at% of the main component ceramic. The thickness of the dielectric layer 11 is, for example, 1 μm to 15 μm, 2 μm to 12 μm, or 3 μm to 10 μm. The thickness of the dielectric layer 11 can be measured by observing the cross-section of the multilayer ceramic capacitor 100 using a SEM (scanning electron microscope), measuring the thickness at 10 points for each of the 10 different dielectric layers 11, and deriving the average value of all measured points.

[0046] Additives may be added to the dielectric layer 11. Examples of additives added to the dielectric layer 11 include oxides of zirconium (Zr), hafnium (Hf), magnesium (Mg), manganese (Mn), molybdenum (Mo), vanadium (V), chromium (Cr), rare earth elements (yttrium (Y), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), and ytterbium (Yb)), or oxides containing cobalt (Co), nickel (Ni), lithium (Li), boron (B), sodium (Na), potassium (K), or silicon (Si), or glasses containing cobalt, nickel, lithium, boron, sodium, potassium, or silicon.

[0047] like Figure 2 As illustrated, the regions of the inner electrode layer 12 connected to the external electrode 20a and the inner electrode layer 12 connected to the external electrode 20b, which are opposite each other, are the regions in the multilayer ceramic capacitor 100 that generate capacitance. Therefore, this region that generates capacitance is called the capacitor section 14. That is, the capacitor section 14 is the region of adjacent inner electrode layers 12 connected to different external electrodes that are opposite each other.

[0048] The region of the internal electrode layers 12 connected to the external electrode 20a that is opposite to each other without being separated from the internal electrode layers 12 connected to the external electrode 20b is called the end edge 15. Similarly, the region of the internal electrode layers 12 connected to the external electrode 20b that is opposite to each other without being separated from the internal electrode layers 12 connected to the external electrode 20a is also the end edge 15. In other words, the end edge 15 is the region of the internal electrode layers 12 connected to the same external electrode that is opposite to the internal electrode layers 12 connected to different external electrodes. The end edge 15 is a region that does not generate capacitance.

[0049] like Figure 3 As illustrated, in the main body 10, the side edge 16 is a region that covers the ends (ends in the Y-axis direction) of the two side surfaces of the dielectric layer 11 and the internal electrode layer 12. That is, the side edge 16 is a region located outside the capacitor section 14 in the Y-axis direction. The side edge 16 is also a region that does not generate capacitance.

[0050] In the YZ section, the outer periphery of the capacitor portion 14 is formed by the cover layer 13 and the side edges 16. Therefore, the portion forming the outer periphery of the capacitor portion 14 in the YZ section will be generally referred to as the outer periphery below. Furthermore, the cover layer 13 refers to the portion of the outer periphery that is above the uppermost inner electrode layer 12 in the Z-axis direction in the YZ section. Thus, the capacitor portion 14 and a pair of side edges are sandwiched by two layers of cover layer 13.

[0051] Figure 4 (a) is an enlarged cross-sectional view near the external electrode 20a. Figure 4 (b) is an enlarged cross-sectional view near the external electrode 20b. Figure 4 (a) and Figure 4 In (b), the shading is omitted. For example... Figure 4 (a) and Figure 4 As illustrated in (b), the external electrodes 20a and 20b have a structure in which a plating layer 22 is provided on a base layer 21. The base layer 21 is mainly composed of nickel, copper, etc. The base layer 21 may contain ceramic particles as a common material, or it may contain glass. The plating layer 22 is mainly composed of metals such as nickel, copper, aluminum, zinc, tin, or alloys of two or more of these metals. The plating layer 22 may be a plating layer with a single metal composition, or it may be multiple plating layers with different metal compositions. For example, the plating layer 22 has a structure in which a first plating layer 23, a second plating layer 24, and a third plating layer 25 are formed sequentially from the base layer 21 side. The first plating layer 23 is, for example, a copper plating layer. The second plating layer 24 is, for example, a nickel plating layer. The third plating layer 25 is, for example, a tin plating layer.

[0052] Figure 5 This is a schematic cross-sectional view of dielectric layer 11. (See diagram below.) Figure 5 As illustrated, the dielectric layer 11 has a structure formed by sintering multiple dielectric particles 30 constituting the main phase. For example, the dielectric layer 11 may have one dielectric particle 30 in the thickness direction, or it may be as follows: Figure 5 That is, a structure in which multiple dielectric particles 30 are continuous through grain boundaries.

[0053] Here, the elements in the solid solution of dielectric particles 30 are studied. A characteristic of perovskite oxides such as barium titanate is that there are two types of cation sites in the crystal. The site occupied by the +2 valence metal element is called the A site, and the site occupied by the +4 valence metal element is called the B site. The ion size at the A site is relatively large. Therefore, at the A site, metal elements with a coordinating ion radius greater than 0.1 nm are preferred. At the B site, metal elements with a relatively small coordinating ion size are preferred. When the combined valence of the metal elements at the A and B sites is +6, it becomes a defect-free, ideal perovskite oxide.

[0054] However, when base metals are used in the internal electrode layer, during high-temperature reduction firing, some of the +4 valence metal elements will become +3 valence. The +3 valence metal will exhibit high conductivity due to its 3d electrons, and the concentration of oxide ion defects (sometimes called oxygen defects) will also increase due to the requirement for electroneutrality. Therefore, in multilayer ceramic capacitors made from pure perovskite materials, the insulation after firing is low, the reliability is poor, and it may be impractical.

[0055] When rare earth elements are ionized, their valence is typically +3 unless treated in a special atmosphere. Furthermore, rare earth ions are smaller than +2 ions at site A, but larger than +4 ions at site B. Therefore, rare earth elements can occupy either site A or site B. When a rare earth ion occupies site A, it becomes positively charged (excessive charge compared to the original site), thus becoming a donor in the electronic structure and able to donate electrons into the band structure. When a rare earth ion occupies site B, it becomes less charged (insufficient charge compared to the original site), thus becoming an acceptor and able to reclaim electrons, increasing the defect concentration of oxide ions.

[0056] When rare earth elements (REEs) that tend to occupy only the A-site of the perovskite structure in the reduced-fired state are added, the REE, acting as a donor, reduces the concentration of oxide ion defects but increases the electron concentration, thus leading to conduction. In the case of occupying only the B-site of the perovskite structure in the reduced-fired state, although the effect of the electron donor can be offset, the concentration of oxide ion defects will further increase as compensation for insufficient charge, thus detrimental to reliability. However, if separate rare earth elements capable of occupying both the A-site and B-site are added, they can occupy both sites simultaneously in a certain proportion during the firing stage, causing the donor and acceptor effects to cancel each other out, thereby suppressing the generation of oxide ion defects and the increase in electron concentration. For the reasons stated above, it has been conventionally desirable to use only rare earth elements with a limited and appropriate range of ion sizes that have an affinity for both the A-site and B-site as additives, reducing electron and oxide ion defects through the occupation of both sites to improve reliability.

[0057] However, when adding individual rare earth elements, their distribution at the A and B sites, which are the destinations for solid solution, cannot be avoided. This distribution is naturally determined by the combined influence of various additives other than rare earth elements and firing conditions. Furthermore, it is possible that not all added rare earth elements react with the perovskite material and dissolve during firing. In perovskite materials used in multilayer ceramic capacitors, additives other than rare earth elements mostly include transition metals from period 4 (vanadium to copper), period 5 (zirconium to silver), zinc, magnesium, aluminum, calcium, and strontium. Additionally, silicon is added in the form of silicon oxide (SiO2) to form a liquid phase during firing and improve sinterability. Among these additives, period 4 transition metals, period 5 transition metals, zinc, magnesium, aluminum, calcium, and strontium can readily dissolve in perovskite materials when cationized, but silicon cannot dissolve in perovskite oxide crystals due to its different chemical properties. On the other hand, rare earth elements and silicon dioxide can readily form rare earth element silicates. Therefore, there is a possibility that some of the added rare earth elements cannot be dissolved in the perovskite material during firing, and remain as rare earth element silicates as crystalline impurities relative to the perovskite phase after firing. Even additives other than rare earth elements, if not dissolved in the perovskite, will also exist in the form of silicate crystals.

[0058] When adding rare earth elements, consider the following approach: If multiple rare earth elements are intentionally used, then rare earth elements suitable for the A-site and the B-site of the perovskite material must be used separately. When a rare earth element with a large ion size is prepared for the A-site and a rare earth element with a small ion size is prepared for the B-site, and both rare earth elements are coordinatingly dissolved in the A-site and B-site respectively, both rare earth elements can be efficiently dissolved in the perovskite material. Moreover, the combined valence of the two rare earth element ions is +6, which represents a state where the donor and acceptor effects are exactly canceled out in perovskite oxide structures. Therefore, the generation of oxide ion defects and electrons can be suppressed. When adding a single rare earth element, the proportion of residue at site A or site B can vary depending on factors such as firing temperature or firing atmosphere. Therefore, it is possible that the solution at both sites cannot always be ideal. However, when two rare earth elements with different site orientations are added, it is expected that the solution at both sites A and B will always be in the desired form, regardless of changes in firing conditions.

[0059] If all additives other than silicon dioxide react with the perovskite, the resulting structure after firing will consist of a phase of oxide particles with perovskite as the basic component and a phase primarily composed of silicon dioxide. The phase primarily composed of silicon dioxide is not a rare-earth silicate, but rather a segregated phase with silicon dioxide as the main component. Silicon dioxide being the main component in the segregated phase means, for example, that the silicon dioxide content in the segregated phase is 50 mol% or more.

[0060] For example, when the B site of the perovskite material is 100 mol%, the amount of silicon oxide added is about 2 mol% or less, and at most about 5 mol%. Therefore, in terms of volume, there are overwhelmingly more perovskite-type oxide particles, and the segregated phase with silicon oxide as the main component exists on the outside of the perovskite material particles and at the grain boundaries.

[0061] When comparing metal oxides and silicon oxide, both contain oxygen atoms, but their bonding mechanisms are quite different. It is well known that in metal oxides, oxygen is ionized into oxide ions (O₂). 2- In silicon oxide, defects can diffuse, and in fact, certain metal oxides have been put into practical use as ionic conductors. On the other hand, in silicon oxide, in the case of crystalline silicon oxide, or in the case of glass formation, oxygen and silicon form strong covalent bonds. In order for oxygen to diffuse in ionic form, the breaking and reforming of these strong covalent bonds must be repeated. Therefore, the diffusion of oxide ions in silicon oxide is very slow and can hardly be observed.

[0062] As a result, when additives other than silicon oxide are used to form a perovskite phase within the oxide lattice, resulting in a structure where only silicon oxide remains at the grain boundaries on the outer side of the oxide, the energy barrier for oxide ion defects to diffuse across the grain boundaries increases. Therefore, the migration rate of oxide ion defects as a whole material can be suppressed. Consequently, the rate at which oxide ion defects accumulate at the electrode-oxide interface under applied voltage is slowed, improving the reliability of multilayer ceramic capacitors.

[0063] Based on the above research results, the multilayer ceramic capacitor 100 of this embodiment has a structure that can ensure reliability.

[0064] Figure 6 This is an enlarged cross-sectional view of the periphery of dielectric particle 30. (For example...) Figure 6 As illustrated, a grain boundary triplet is formed by three or more dielectric particles 30. A grain boundary triplet refers to the boundary of three or more dielectric particles. A segregated phase 40, mainly composed of silicon oxide, is disposed at the grain boundary triplet.

[0065] The dielectric particles 30 comprise: a first rare earth element with a large ionic radius; and a second rare earth element with a smaller ionic radius than the first rare earth element. In this embodiment, at least one element selected from lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, and gadolinium is used as the first rare earth element. At least one element selected from yttrium, scandium, holmium, erbium, thulium, ytterbium, and lutetium is used as the second rare earth element.

[0066] Table 1 shows the ionic radii of the six coordination groups of each rare earth element. The source of Table 1 is "RD Shannon, Acta Crystallogr., A32, 751 (1976)".

[0067] [Table 1]

[0068]

[0069] Through in-depth research, the inventors of this invention discovered that by including both the first and second rare earth elements in the dielectric particles 30, and with an atomic ratio of the first to the second rare earth element of 65:35 to 35:65, a characteristic structure can be formed at the grain boundaries of the dielectric particles 30. Furthermore, by configuring a segregated phase 40, primarily composed of silicon oxide, at the three points of the grain boundaries of the dielectric particles 30, the migration of oxide ions can be suppressed. By suppressing the migration of oxide ions, the reliability of the dielectric layer 11 can be ensured. Here, when the dielectric particles 30 include multiple elements selected from lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, and gadolinium as the first rare earth element, the atomic number of the first rare earth element is the total atomic number of these multiple first rare earth elements. When the dielectric particles 30 contain multiple elements selected from yttrium, scandium, holmium, erbium, thulium, ytterbium, and lutetium as second rare earth elements, the number of atoms of the aforementioned second rare earth elements is the total number of atoms of these multiple second rare earth elements.

[0070] There are no particular restrictions on the first rare earth element, as long as it is selected from at least one element among lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, and gadolinium. Similarly, there are no particular restrictions on the second rare earth element, as long as it is selected from at least one element among yttrium, scandium, holmium, erbium, thulium, ytterbium, and lutetium. Preferred choices are europium as the first rare earth element and yttrium as the second. Although the detailed mechanism is not yet fully understood, it is generally accepted that when europium and yttrium are combined, sintering and solid solution processes proceed particularly rapidly, thus achieving satisfactory results under the same firing conditions.

[0071] In the dielectric particles 30, if the content of the first rare earth element is too low relative to the content of the second rare earth element, the reliability may decrease. On the other hand, if the content of the first rare earth element is too high relative to the content of the second rare earth element, the insulation may be insufficient, making it unusable as a dielectric. In this embodiment, the atomic ratio of the first rare earth element to the second rare earth element is preferably 60:40 to 40:60, more preferably 55:45 to 45:55.

[0072] When the combined content of the first and second rare earth elements in the dielectric particles 30 is too low, they may not be able to adequately occupy the A and B sites of the perovskite material. Therefore, it is preferable to set a lower limit for the combined content of the first and second rare earth elements in the dielectric particles 30. In this embodiment, the combined content of the first and second rare earth elements in the dielectric particles 30 is preferably 1.5 mol% or more, more preferably 2.0 mol% or more, and even more preferably 3.0 mol% or more, when the B site metal element such as titanium is set to 100 mol%.

[0073] On the other hand, if the combined content of the first and second rare earth elements in the dielectric particles 30 is too high, the relative permittivity may be excessively reduced to less than 1000. Therefore, it is preferable to set an upper limit on the combined content of the first and second rare earth elements in the dielectric particles 30. In this embodiment, the combined content of the first and second rare earth elements in the dielectric particles 30 is preferably 6.0 mol% or less when the B-site metal element such as titanium is set to 100 mol%, more preferably 5.0 mol% or less, and even more preferably 4.5 mol% or less.

[0074] When the amount of segregated phase 40 in the dielectric layer 11 is too small, it may not be able to sufficiently suppress the migration of oxide ion defects. Therefore, it is preferable to set a lower limit on the amount of segregated phase 40 in the dielectric layer 11. In this embodiment, it is preferable that in a cross section of the dielectric layer 11 including the stacking direction, any one segregated phase 40 contacts 50% or more of the dielectric particles 30 contained in the dielectric layer 11, more preferably any one segregated phase 40 contacts 75% or more of the dielectric particles 30, and even more preferably any one segregated phase 40 contacts 90% or more of the dielectric particles 30.

[0075] Furthermore, in the cross-section of the dielectric layer 11 including the stacking direction, the area ratio of the segregated phase 40 is preferably 0.1% or more, more preferably 0.5% or more, and even more preferably 1.0% or more. The area ratio of the segregated phase 40 is the ratio of the total area of ​​the black parts to the overall area of ​​the SEM image after binarization.

[0076] On the other hand, if there is too much segregated phase 40 in the dielectric layer 11, the relative permittivity of the sintered body as a whole may decrease, thus failing to achieve its function as a dielectric. Therefore, it is preferable to set an upper limit on the amount of segregated phase 40 in the dielectric layer 11. In this embodiment, the area ratio of segregated phase 40 in the cross-section of the dielectric layer 11 including the stacking direction is preferably 10% or less, more preferably 5% or less, and even more preferably 3% or less.

[0077] When the segregated phase 40 is too small, it may not be able to sufficiently suppress the migration of oxide ions. Therefore, it is preferable to set a lower limit for the average diameter of the segregated phase 40. In this embodiment, the average diameter of the segregated phase 40 is preferably 10 nm or more, more preferably 15 nm or more, and even more preferably 20 nm or more. Regarding the average diameter of the segregated phase 40, the SEM image can be binarized, and the diameter of a circle having an area equal to the area of ​​each black part can be calculated, based on its average value.

[0078] On the other hand, if the segregated phase 40 is too large, it may lead to a decrease in the relative permittivity of the sintered body as a whole, making it difficult to achieve the function of a dielectric. Therefore, it is preferable to set an upper limit on the average diameter of the segregated phase 40. In this embodiment, the average diameter of the segregated phase 40 is preferably 200 nm or less, more preferably 150 nm or less, and even more preferably 100 nm or less.

[0079] Next, the manufacturing method of the multilayer ceramic capacitor 100 will be described. Figure 7 This is a flowchart illustrating the manufacturing method of a multilayer ceramic capacitor 100.

[0080] (Raw material powder production process)

[0081] First, a dielectric material for forming the dielectric layer 11, a cover material for forming the cover layer 13, and a reverse patterning material for forming the side edges 16 are prepared. The dielectric material, cover material, and reverse patterning material comprise barium titanate powder having a perovskite structure. For example, barium titanate is a tetragonal compound with a perovskite structure, exhibiting a high relative permittivity. Barium titanate powder is typically synthesized by reacting titanium raw materials such as titanium dioxide with barium raw materials such as barium carbonate. Various methods are known conventionally for synthesizing barium titanate powder, such as solid-state methods, sol-gel methods, and hydrothermal methods. In this embodiment, any of these methods can be employed.

[0082] To the obtained barium titanate powder, specified additive compounds are added according to the intended purpose to prepare dielectric materials, coating materials, and reverse-patterned materials, respectively. Examples of additive compounds include oxides of zirconium, hafnium, magnesium, manganese, molybdenum, vanadium, chromium, and rare earth elements (yttrium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, and ytterbium), or oxides containing cobalt, nickel, lithium, boron, sodium, potassium, or silicon, or glasses containing cobalt, nickel, lithium, boron, sodium, potassium, or silicon. The oxides of the first and second rare earth elements can be added at the same time, preferably with the same or smaller particle size as or less than that of the first rare earth element. Alternatively, coordination compound raw materials can be used as rare earth raw materials. In this case, the rare earth elements are preferably added after the addition of other additives, and more preferably added last.

[0083] (Coating process)

[0084] A wet mixture is made by adding binders such as polyvinyl butyral (PVB) resin, organic solvents such as ethanol and toluene, and plasticizers to the dielectric material. Using the resulting slurry, a dielectric green sheet 51 is coated onto a substrate by, for example, a molding or doctor blade method and then dried. The substrate is, for example, a polyethylene terephthalate (PET) film.

[0085] (Printing process)

[0086] Next, as Figure 8 As illustrated in (a), an internal electrode pattern 52, alternately led to a pair of external electrodes of different polarities, is configured by printing a metal conductive paste containing an organic binder onto the surface of the dielectric sheet 51 using screen printing, gravure printing, or the like. Ceramic particles are added to the metal conductive paste as a co-material. The main component of the ceramic particles is not particularly limited, but it is preferably the same as the main component ceramic of the dielectric layer 11. For example, barium titanate with an average particle size of 50 nm or less can be uniformly dispersed.

[0087] Next, binders such as ethyl cellulose and organic solvents such as terpineols are added to the reverse pattern material, and the mixture is then kneaded using a roller mill to obtain the reverse pattern paste. For example... Figure 8 As illustrated in (a), on the dielectric green sheet 51, a reverse pattern paste is printed in the peripheral area where the internal electrode pattern 52 is not printed to configure the reverse pattern 53, filling the step difference with the internal electrode pattern 52. The dielectric green sheet 51 with the internal electrode pattern 52 and the reverse pattern 53 printed is called a stacking unit.

[0088] After that, as Figure 8 As illustrated in (b), the stacked units are stacked in a manner that alternating between the inner electrode layer 12 and the dielectric layer 11, and in a manner in which the end edges of the inner electrode layer 12 are alternately exposed on both ends of the dielectric layer 11 along its length and are alternately led out to a pair of external electrodes 20a, 20b with different polarities. For example, the number of layers in the inner electrode pattern 52 is 100 to 1000.

[0089] (Crimping process)

[0090] Next, binders such as ethyl cellulose and organic solvents such as terpineols are added to the covering material, and the mixture is kneaded using a roller mill to obtain the covering sheet 54. Figure 9 As illustrated, a predetermined number of cover sheets 54 are stacked on top of each other in the laminate obtained by stacking the lamination units and then heat-pressed together. Then, they are cut into predetermined sheet sizes (e.g., 1.0 mm × 0.5 mm).

[0091] (Coating process)

[0092] After the ceramic laminate obtained as described above is subjected to a debinding treatment in an N2 atmosphere, an atmospheric atmosphere, etc., a metal paste is applied by an impregnation method to form the base layer of the external electrodes 20a and 20b.

[0093] (Firing process)

[0094] Subsequently, in a reducing atmosphere formed by a mixture of N2, H2, and H2O gases, the temperature is raised to 700°C to 1000°C at a rate of 100°C / h to 300°C / h, and held for 1 to 4 hours for debinding. Then, the heating rate is increased to 100°C / h to 400°C / h, raising the temperature to 1100°C to 1300°C, and held for 0.1 to 4 hours for firing, followed by cooling to room temperature. The firing atmosphere can be the same as that used for debinding, but increasing the H2 ratio to promote sintering can further promote segregation.

[0095] (Re-oxidation process)

[0096] Then, it can be re-oxidized in an N2 atmosphere at 600℃~1000℃.

[0097] (Platinum coating process)

[0098] Then, through a plating process, metals such as Cu, Ni, and Sn are applied to the substrate layer of the external electrodes 20a and 20b. Through the above processes, the multilayer ceramic capacitor 100 is completed.

[0099] In the above embodiments, a multilayer ceramic capacitor was described as an example of a multilayer ceramic electronic component, but it is not limited to this. For example, other multilayer ceramic electronic components such as varistors and thermistors can also be used.

[0100] [Example]

[0101] Next, we will fabricate a multilayer ceramic capacitor according to the embodiment and investigate its characteristics.

[0102] (Example 1)

[0103] Weighing was performed so that, with barium titanate produced by solid-state synthesis at 100 mol%, europium was 1.8 mol% (0.9 mol% in the form of Eu₂O₃), yttrium was 1.8 mol% (0.9 mol% in the form of Y₂O₃), and silicon was 1.0 mol% (1.0 mol% in the form of SiO₂). Magnesium, vanadium, manganese, and zirconium were added as additives. These mixed powders were dispersed with ethanol, toluene, and a dispersant using zirconium oxide beads. After dispersion, the slurry was separated from the zirconium oxide beads by passing it through a filter, and then mixed with PVB (polyvinyl butyral) resin as a binder to obtain a slurry. Therefore, in Example 1, the atomic ratio of the first rare earth element to the second rare earth element was 50:50.

[0104] The slurry obtained as described above is applied to a PET film as a 0.5 μm thick dielectric green sheet using a die-coating machine. After drying the dielectric green sheet, nickel paste is printed as the internal electrode pattern. The dielectric green sheets with the printed internal electrode pattern are stacked. At this time, the positive electrode pattern and the negative electrode pattern are stacked alternately. Dielectric layers of the same composition, each 50 μm thick, are stacked on top and bottom as protective layers and then heat-pressed. The plate-shaped molded body thus produced is sintered and cut into individual pieces (chips) with a size of 1.0 mm × 0.5 mm. The two opposite sides of the internal electrode leads exposed on the cut chips are dipped in nickel paste to form terminal electrodes.

[0105] The sheet prepared as described above was heated to 800°C at a heating rate of 100°C / h in a reducing atmosphere formed by a N2-H2-H2O mixture and held for 2 hours to remove the binder. Then, the heating rate was increased to 200°C / h, raising the temperature to 1250°C and holding for 2 hours, before lowering the temperature to room temperature. The sintered sheet was then re-oxidized at 800°C in a dry N2 atmosphere. This yields a multilayer ceramic capacitor.

[0106] (Comparative Example 1)

[0107] In Comparative Example 1, weighings were performed such that, with barium titanate prepared by solid-state synthesis at 100 mol%, europium was 3.6 mol% (1.8 mol% in the form of Eu₂O₃), and silicon was 1.0 mol% (1.0 mol% in the form of SiO₂). Yttrium was not used. Other conditions were the same as in Example 1.

[0108] (Comparative Example 2)

[0109] In Comparative Example 2, weighings were performed such that, with barium titanate prepared by solid-state synthesis at 100 mol%, yttrium was 3.6 mol% (1.8 mol% in the form of Y₂O₃) and silicon was 1.0 mol% (1.0 mol% in the form of SiO₂). Europium was not used. Other conditions were the same as in Example 1.

[0110] (Presence or absence of segregated phase)

[0111] For each sample of Example 1 and Comparative Examples 1 and 2, BSE images (reflected electron images) of the cross-section of the dielectric layer were obtained. Figure 10 This is a diagram obtained by tracking the BSE image of the sample from Example 1. Figure 11 This is a diagram obtained by tracking the BSE image of the sample in Comparative Example 1. Figure 12 This is a diagram obtained by tracking the BSE image of the sample in Comparative Example 2.

[0112] like Figure 10 As shown, in the sample of Example 1, a segregated phase 40, mainly composed of silicon oxide, was identified at the three points of the dielectric particles in the main phase. Figure 10 (The black portion). This can be attributed to the use of europium as the first rare earth element and yttrium as the second rare earth element, with an atomic ratio of 50:50 between the first and second rare earth elements. In contrast, no segregated phase with silicon oxide as the main component was identified in the samples of Comparative Examples 1 and 2. This can be attributed to the use of only either the first or second rare earth element.

[0113] (Reliability test)

[0114] Next, reliability tests were conducted on 10 samples for Example 1 and Comparative Examples 1 and 2, respectively. In the reliability tests, the behavior of continuously applying a voltage of 50V per 1μm at a temperature of 150°C until insulation breakdown was investigated. Figure 13 This represents the results of Example 1. Figure 14 This indicates the result of comparing Example 1. Figure 15 This indicates the result of comparison example 2. In Figures 13-15 In any of the graphs, the horizontal axis represents the elapsed time (minutes), and the vertical axis represents the current (μA).

[0115] If the average lifespan is over 1000 minutes, the reliability test is judged as qualified "0"; otherwise, it is judged as unqualified "×".

[0116] like Figure 13 As shown, in Example 1, the average time until insulation breakdown was approximately 10,000 minutes, with a maximum of 19,000 minutes. Therefore, the reliability test result for Example 1 was deemed satisfactory, "0". Thus, Example 1 yielded a remarkable result of achieving sufficient reliability. This can be attributed to the fact that the migration of oxide ions was suppressed by configuring a segregated phase, primarily composed of silicon oxide, at the three points of the dielectric particles.

[0117] And such Figure 14 As shown, in Comparative Example 1, the average time until insulation breakdown was approximately 600 minutes, with a maximum of approximately 900 minutes. Additionally, as... Figure 15 As shown, in Comparative Example 2, the average time until insulation breakdown was approximately 300 minutes, with a maximum of 500 minutes. Therefore, the reliability tests of Comparative Examples 1 and 2 were judged as unqualified "×". Based on these results, it can be considered that in Comparative Examples 1 and 2, there was no segregation of a phase with silicon oxide as the main component, and therefore the migration of oxide ions could not be suppressed. These results are shown in Table 2.

[0118] [Table 2]

[0119]

[0120] (Example 2)

[0121] In Example 2, weighings were performed such that, with barium titanate prepared by solid-state synthesis at 100 mol%, gadolinium was 2.34 mol% (1.17 mol% as Gd₂O₃), yttrium was 1.26 mol% (0.63 mol% as Y₂O₃), and silicon was 1.0 mol% (1.0 mol% as SiO₂). Therefore, the atomic ratio of the first rare earth element to the second rare earth element was 65:35. Other conditions were the same as in Example 1.

[0122] (Example 3)

[0123] In Example 3, weighings were performed such that, with barium titanate prepared by solid-state synthesis at 100 mol%, gadolinium was 1.8 mol% (0.9 mol% as Gd₂O₃), yttrium was 1.8 mol% (0.9 mol% as Y₂O₃), and silicon was 1.0 mol% (1.0 mol% as SiO₂). Therefore, the atomic ratio of the first rare earth element to the second rare earth element was 50:50. Other conditions were the same as in Example 1.

[0124] (Example 4)

[0125] In Example 4, weighings were performed such that, with 100 mol% barium titanate prepared by solid-state synthesis, gadolinium was 1.26 mol% (0.63 mol% in the form of Gd₂O₃), yttrium was 2.34 mol% (1.17 mol% in the form of Y₂O₃), and silicon was 1.0 mol% (1.0 mol% in the form of SiO₂). Therefore, the atomic ratio of the first rare earth element to the second rare earth element was 35:65. Other conditions were the same as in Example 1.

[0126] (Example 5)

[0127] In Example 5, weighings were performed such that, with barium titanate prepared by solid-state synthesis at 100 mol%, europium was 2.34 mol% (1.17 mol% in the form of Eu₂O₃), yttrium was 1.26 mol% (0.63 mol% in the form of Y₂O₃), and silicon was 1.0 mol% (1.0 mol% in the form of SiO₂). Therefore, the atomic ratio of the first rare earth element to the second rare earth element was 65:35. Other conditions were the same as in Example 1.

[0128] (Example 6)

[0129] In Example 6, weighings were performed such that, with 100 mol% barium titanate prepared by solid-state synthesis, europium was 1.26 mol% (0.63 mol% in the form of Eu₂O₃), yttrium was 2.34 mol% (1.17 mol% in the form of Y₂O₃), and silicon was 1.0 mol% (1.0 mol% in the form of SiO₂). Therefore, the atomic ratio of the first rare earth element to the second rare earth element was 35:65. Other conditions were the same as in Example 1.

[0130] (Example 7)

[0131] In Example 7, weighings were performed such that, with 100 mol% barium titanate prepared by solid-state synthesis, lanthanum was 1.8 mol% (0.9 mol% as La₂O₃), yttrium was 1.8 mol% (0.9 mol% as Y₂O₃), and silicon was 1.0 mol% (1.0 mol% as SiO₂). Therefore, the atomic ratio of the first rare earth element to the second rare earth element was 50:50. Other conditions were the same as in Example 1.

[0132] (Example 8)

[0133] In Example 8, weighings were performed such that, with 100 mol% barium titanate prepared by solid-state synthesis, neodymium was 1.8 mol% (0.9 mol% as Nd₂O₃), yttrium was 1.8 mol% (0.9 mol% as Y₂O₃), and silicon was 1.0 mol% (1.0 mol% as SiO₂). Therefore, the atomic ratio of the first rare earth element to the second rare earth element was 50:50. Other conditions were the same as in Example 1.

[0134] (Example 9)

[0135] In Example 9, weighings were performed such that, with barium titanate prepared by solid-state synthesis at 100 mol%, gadolinium was 1.8 mol% (0.9 mol% as Gd₂O₃), scandium was 1.8 mol% (0.9 mol% as Sc₂O₃), and silicon was 1.0 mol% (1.0 mol% as SiO₂). Therefore, the atomic ratio of the first rare earth element to the second rare earth element was 50:50. Other conditions were the same as in Example 1.

[0136] (Example 10)

[0137] In Example 10, weighings were performed such that, with barium titanate prepared by solid-state synthesis at 100 mol%, europium was 1.8 mol% (0.9 mol% in the form of Eu₂O₃), scandium was 1.8 mol% (0.9 mol% in the form of Sc₂O₃), and silicon was 1.0 mol% (1.0 mol% in the form of SiO₂). Therefore, the atomic ratio of the first rare earth element to the second rare earth element was 50:50. Other conditions were the same as in Example 1.

[0138] (Example 11)

[0139] In Example 11, weighings were performed such that, with barium titanate prepared by solid-state synthesis at 100 mol%, gadolinium was 1.8 mol% (0.9 mol% in the form of Gd₂O₃), holmium was 1.8 mol% (0.9 mol% in the form of Ho₂O₃), and silicon was 1.0 mol% (1.0 mol% in the form of SiO₂). Therefore, the atomic ratio of the first rare earth element to the second rare earth element was 50:50. Other conditions were the same as in Example 1.

[0140] (Example 12)

[0141] In Example 12, weighings were performed such that, with barium titanate prepared by solid-state synthesis at 100 mol%, gadolinium was 1.8 mol% (0.9 mol% in the form of Gd₂O₃), holmium was 1.8 mol% (0.9 mol% in the form of Ho₂O₃), and silicon was 1.0 mol% (1.0 mol% in the form of SiO₂). Therefore, the atomic ratio of the first rare earth element to the second rare earth element was 40:60. Other conditions were the same as in Example 1.

[0142] (Example 13)

[0143] In Example 13, weighings were performed such that, with barium titanate prepared by solid-state synthesis at 100 mol%, gadolinium was 1.8 mol% (0.9 mol% in the form of Gd₂O₃), ytterbium was 1.8 mol% (0.9 mol% in the form of Y₂O₃), and silicon was 1.0 mol% (1.0 mol% in the form of SiO₂). Therefore, the atomic ratio of the first rare earth element to the second rare earth element was 50:50. Other conditions were the same as in Example 1.

[0144] (Comparative Example 3)

[0145] In Comparative Example 3, weighings were performed such that, assuming barium titanate prepared by solid-state synthesis was 100 mol%, terbium was 1.8 mol% (0.9 mol% in the form of Tb₂O₃), ytterbium was 1.8 mol% (0.9 mol% in the form of Y₂O₃), and silicon was 1.0 mol% (1.0 mol% in the form of SiO₂). Therefore, the atomic ratio of the first rare earth element to the second rare earth element was 50:50. Other conditions were the same as in Example 1.

[0146] (Comparative Example 4)

[0147] In Comparative Example 4, weighings were performed such that, with 100 mol% barium titanate prepared by solid-state synthesis, dysprosium was 1.8 mol% (0.9 mol% in the form of Dy₂O₃), ytterbium was 1.8 mol% (0.9 mol% in the form of Y₂O₃), and silicon was 1.8 mol% (1.8 mol% in the form of SiO₂). Therefore, the atomic ratio of the first rare earth element to the second rare earth element was 50:50. Other conditions were the same as in Example 1.

[0148] (Comparative Example 5)

[0149] In Comparative Example 5, weighings were performed such that, with 100 mol% barium titanate prepared by solid-state synthesis, dysprosium was 1.8 mol% (0.9 mol% in the form of Dy₂O₃), holmium was 1.8 mol% (0.9 mol% in the form of Ho₂O₃), and silicon was 1.0 mol% (1.0 mol% in the form of SiO₂). Therefore, the atomic ratio of the first rare earth element to the second rare earth element was 50:50. Other conditions were the same as in Example 1.

[0150] (Comparative Example 6)

[0151] In Comparative Example 6, weighings were performed such that, with barium titanate prepared by solid-state synthesis at 100 mol%, gadolinium was 1.8 mol% (0.9 mol% in the form of Gd₂O₃), dysprosium was 1.8 mol% (0.9 mol% in the form of Dy₂O₃), and silicon was 1.0 mol% (1.0 mol% in the form of SiO₂). Therefore, the atomic ratio of the first rare earth element to the second rare earth element was 50:50. Other conditions were the same as in Example 1.

[0152] (Comparative Example 7)

[0153] In Comparative Example 7, weighings were performed such that, with barium titanate prepared by solid-state synthesis at 100 mol%, neodymium was 3.6 mol% (1.8 mol% in the form of Nd₂O₃) and silicon was 1.0 mol% (1.0 mol% in the form of SiO₂). No second rare earth element was used. Other conditions were the same as in Example 1.

[0154] (Comparative Example 8)

[0155] In Comparative Example 8, weighings were performed such that, with barium titanate prepared by solid-state synthesis at 100 mol%, gadolinium was 3.6 mol% (1.8 mol% in the form of Gd₂O₃) and silicon was 1.0 mol% (1.0 mol% in the form of SiO₂). No second rare earth element was used. Other conditions were the same as in Example 1.

[0156] (Presence or absence of segregated phase)

[0157] For each sample of Examples 2-13 and Comparative Examples 3-8, BSE (Browser Electron Reflection) images of the cross-section of the dielectric layer were obtained to confirm the presence or absence of segregated phase 40. In Examples 2-13, segregated phase 40, mainly composed of silicon oxide, was confirmed at the three points of the dielectric particles in the main phase. This can be attributed to the use of any one of lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, and gadolinium as the first rare earth element, and any one of yttrium, scandium, holmium, erbium, thulium, ytterbium, and lutetium as the second rare earth element, with the atomic ratio of the first rare earth element to the second rare earth element being 65:35 to 35:65.

[0158] In Comparative Examples 3-8, no segregated phase with silicon oxide as the main component was identified. This can be attributed to the fact that terbium was used as the first rare earth element in Comparative Example 3, dysprosium was used as the first rare earth element in Comparative Examples 4 and 5, dysprosium was used as the second rare earth element in Comparative Example 6, and only the first rare earth element was used in Comparative Examples 7 and 8.

[0159] (Reliability test)

[0160] Next, similarly to Example 1, reliability tests were performed on 10 samples for Examples 2-13 and Comparative Examples 3-8. The average lifetime until insulation breakdown was 4500 minutes in Example 2, 10000 minutes in Example 3, 5500 minutes in Example 4, 5500 minutes in Example 5, 7500 minutes in Example 6, 1100 minutes in Example 7, 1800 minutes in Example 8, 1200 minutes in Example 9, 1300 minutes in Example 10, 4500 minutes in Example 11, 2800 minutes in Example 12, 1300 minutes in Example 13, 300 minutes in Comparative Example 3, 600 minutes in Comparative Example 4, 800 minutes in Comparative Example 5, 0 minutes in Comparative Example 6, 0 minutes in Comparative Example 7, and 0 minutes in Comparative Example 8.

[0161] Therefore, the reliability tests of Examples 2-13 were all judged to be qualified ("0"). This shows that Examples 2-13 yielded surprisingly high reliability results. This can be attributed to the fact that the migration of oxide ions was suppressed by configuring a segregated phase, primarily composed of silicon oxide, at the three points of the dielectric particles.

[0162] In Comparative Examples 2-8, the reliability tests were judged as unqualified ("×"). Based on these results, it can be considered that in Comparative Examples 2-8, there was no segregation of a phase mainly composed of silicon oxide, thus failing to suppress the migration of oxide ions. These results are shown in Table 3.

[0163] [Table 3]

[0164]

[0165] The embodiments of the present invention have been described in detail above. However, the present invention is not limited to these specific embodiments, and various modifications and alterations can be made within the scope of the spirit of the present invention as set forth in the claims.

Claims

1. A laminated ceramic electronic component, characterized in that, have: A dielectric layer comprising a plurality of dielectric particles containing a first rare earth element and a second rare earth element, wherein the first rare earth element is at least one element selected from lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, and gadolinium, and the second rare earth element is at least one element selected from yttrium, scandium, holmium, erbium, thulium, ytterbium, and lutetium, wherein the atomic ratio of the first rare earth element to the second rare earth element is 65:35 to 35:65, and the plurality of dielectric particles have a segregated phase mainly composed of silicon oxide at the grain boundary three points; Multiple internal electrode layers facing each other across the dielectric layer; and External electrodes electrically connected to the plurality of internal electrode layers.

2. The laminated ceramic electronic component according to claim 1, characterized in that: The segregated phase is adjacent to more than 50% of the dielectric particles in the plurality of dielectric particles.

3. The laminated ceramic electronic component according to claim 1 or 2, characterized in that: The average diameter of the segregated phase is greater than 10 nm.

4. The laminated ceramic electronic component according to any one of claims 1 to 3, characterized in that: In the dielectric particles, the content of the first rare earth element and the second rare earth element is more than 1.5 mol% and less than 6.0 mol%.

5. The laminated ceramic electronic component according to any one of claims 1 to 4, characterized in that: The first rare earth element is europium, and the second rare earth element is yttrium.

6. The laminated ceramic electronic component according to any one of claims 1 to 5, characterized in that: The dielectric particles are mainly composed of ceramic materials with a perovskite structure.

7. The laminated ceramic electronic component according to claim 6, characterized in that: The ceramic material is barium titanate.

8. A dielectric ceramic composition, characterized in that: The device comprises multiple dielectric particles containing a first rare earth element and a second rare earth element. The first rare earth element is selected from at least one element chosen from lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, and gadolinium. The second rare earth element is selected from at least one element chosen from yttrium, scandium, holmium, erbium, thulium, ytterbium, and lutetium. The atomic ratio of the first rare earth element to the second rare earth element is 65:35 to 35:

65. The three grain boundaries of the multiple dielectric particles contain a segregated phase with silicon oxide as the main component.

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