Multilayer capacitor

Abstract

To provide a multilayer capacitor having improved electrode connectivity, excellent electrical characteristics, and reliability.SOLUTION: A multilayer capacitor includes a capacitor body including a dielectric layer and an internal electrode, and an external electrode disposed outer side of the capacitor body. The internal electrode and the dielectric layer include zirconium (Zr). An average content of the zirconium (Zr) with respect to the entire internal electrode is 0.0005 mol% or more and less than 5.0 mol%.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a multilayer capacitor.

Background Art

[0002] Recently, as the multifunctionalization and miniaturization of electronic devices have been rapidly progressing, the miniaturization and performance improvement of electronic components have also been advancing at a high speed. In addition, the requirements for high reliability of electrical devices used in automobiles or network facilities, etc., and electronic components for industrial use have been greatly increasing.

[0003] In order to meet such market requirements, the technological development competition of manual components such as inductors, capacitors, or resistors has been accelerating. In particular, for multilayer ceramic capacitors (MLCCs), which are manual components with continuously increasing applications and usage amounts, many efforts are required to preempt the market with various product developments.

[0004] In addition, a multilayer capacitor is a capacitor manufactured in a form where dielectric layers and internal electrodes are stacked, and is used in various electronic devices such as mobile phones, notebook computers, and LCD TVs.

[0005] Recently, with the development of technology, multilayer capacitors have been required to be miniaturized and have a higher capacitance. For this purpose, technological developments have been carried out to increase the connectivity of the internal electrodes in contact with the dielectric layers to increase the effective electrode area, or to granulate the dielectric material and the internal electrode material.

[0006] However, if the materials are granulated, the melting point may decrease, and the thermal shrinkage start temperature of the materials may decrease. In particular, in the case of the metal materials contained in the internal electrodes, the rate of decrease in the thermal shrinkage start temperature is higher than that of the ceramic materials contained in the dielectric layers, so the difference in the thermal shrinkage temperatures between the dielectric layers and the internal electrodes becomes larger.

[0007] The greater the difference in the thermal shrinkage temperature between the dielectric layer and the internal electrode, the greater the likelihood that the electrode connectivity will deteriorate after firing the dielectric layer and the internal electrode, and the electrical capacitance and reliability of the multilayer capacitor may deteriorate.

[0008] Currently, in order to reduce the difference in the thermal shrinkage temperature between the dielectric layer and the internal electrode, a method of adding a nano-sized barium titanate (BaTiO3) co-material during the manufacture of the internal electrode is used.

[0009] However, if the content of the barium titanate co-material increases, the film density of the internal electrode decreases, and a side effect occurs in which the co-material diffused into the dielectric layer during the firing process increases the thickness of the dielectric layer and decreases the capacitance of the capacitor. Therefore, there is a situation where the development of a new co-material with high thermal stability is required.

Summary of the Invention

Problems to be Solved by the Invention

[0010] One aspect of the embodiment provides a multilayer capacitor with improved electrode connectivity and excellent electrical characteristics and reliability.

[0011] However, the problems to be solved by the embodiment are not limited to the above problems, and can be variously extended within the scope of the technical idea included in the embodiment.

Means for Solving the Problems

[0012] A multilayer capacitor according to an embodiment includes a capacitor body including a dielectric layer and an internal electrode, and an external electrode disposed outside the capacitor body, wherein the internal electrode and the dielectric layer include zirconium (Zr), and the average content of zirconium (Zr) with respect to the entire internal electrode is 0.0005 mol% or more and less than 5.0 mol%.

[0013] The internal electrode may include a conductive metal and zirconium (Zr).

[0014] The dielectric layer contains a main component and a sub-component, and the main component is (Ba 1-X Ca x ) m (Ti 1-y Zr y )O3 (0.995 ≤ m ≤ 1.010, 0 ≤ x ≤ 0.10, 0 < y ≤ 0.20), Ba m (Ti 1-x Zr x )O3 (0.995 ≤ m ≤ 1.010, x ≤ 0.10), or a combination thereof can be included.

[0015] The average content of zirconium (Zr) with respect to the entire internal electrode may be 0.001 mol% to 1.0 mol%.

[0016] The dielectric layer includes a central portion of the dielectric layer and an interface portion of the dielectric layer located on the surface of the central portion of the dielectric layer and in contact with the internal electrode. The average content of zirconium (Zr) with respect to the entire interface portion of the dielectric layer is 0.001 mol% or more and 10.0 mol% or less, and the average content of zirconium (Zr) with respect to the entire central portion of the dielectric layer may be 0 mol% or more and 2.0 mol% or less.

[0017] The dielectric layer includes a plurality of dielectric crystallites, and the dielectric crystallites include first dielectric crystallites located at the interface portion of the dielectric layer and second dielectric crystallites located at the central portion of the dielectric layer. The average particle size of the first dielectric crystallites may be smaller than the average particle size of the second dielectric crystallites.

[0018] The average particle size of the first dielectric crystallites is 50 nm or more and 200 nm or less, and the average particle size of the second dielectric crystallites may be 150 nm or more and 500 nm or less.

[0019] The average thickness of the dielectric layer may be 0.1 μm or more and 5 μm or less.

[0020] The average thickness of the internal electrode may be 0.1 μm or more and 2 μm or less.

[0021] A multilayer capacitor according to another embodiment includes a capacitor body including a dielectric layer and internal electrodes, and external electrodes disposed outside the capacitor body. The internal electrodes include a conductive metal and zirconium (Zr). The dielectric layer includes (Ba 1-X Ca x ) m (Ti 1-y Zr y )O3 (0.995 ≤ m ≤ 1.010, 0 ≤ x ≤ 0.10, 0 < y ≤ 0.20), Ba m (Ti 1-x Zr x )O3 (0.995 ≤ m ≤ 1.010, x ≤ 0.10), or a combination thereof. The average content of zirconium (Zr) with respect to the entire internal electrode is 0.0005 mol% or more and less than 5.0 mol%.

[0022] The average content of zirconium (Zr) with respect to the entire internal electrode may be 0.001 mol% or more and 1.0 mol% or less.

[0023] The dielectric layer includes a central portion of the dielectric layer and an interface portion of the dielectric layer located on the surface of the central portion of the dielectric layer and in contact with the internal electrode. The average content of zirconium (Zr) with respect to the entire interface portion of the dielectric layer is 0.001 mol% or more and 10.0 mol% or less, and the average content of zirconium (Zr) with respect to the entire central portion of the dielectric layer may be 0 mol% or more and 2.0 mol% or more.

[0024] The dielectric layer includes a plurality of dielectric crystal grains. The dielectric crystal grains include first dielectric crystal grains located at the interface portion of the dielectric layer and second dielectric crystal grains located at the central portion of the dielectric layer. The average particle size of the first dielectric crystal grains may be smaller than the average particle size of the second dielectric crystal grains.

[0025] The average particle size of the first dielectric crystal grains is 50 nm or more and 200 nm or less, and the average particle size of the second dielectric crystal grains may be 150 nm or more and 500 nm or less.

[0026] The average thickness of the dielectric layer may be 0.1 μm or more and 5 μm or less.

[0027] The average thickness of the internal electrode may be 0.1 μm or more and 2 μm or less.

Advantages of the Invention

[0028] According to the multilayer capacitor according to the embodiment, there are advantages that the electrode connectivity is improved and the electrical characteristics and reliability are excellent.

[0029] However, the various and beneficial advantages and effects of the present invention are not limited to the above-described content, and should be more easily understood in the process of describing the specific embodiments of the present invention.

Brief Description of the Drawings

[0030]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Modes for Carrying Out the Invention

[0031] Hereinafter, embodiments of the present invention will be described in detail so that those having ordinary knowledge in the technical field to which the present invention pertains can easily implement it with reference to the attached drawings. In order to clearly describe the present invention in the drawings, parts that are unnecessary for the description are omitted, and the same reference numerals are given to the same or similar components throughout the specification. Also, the attached drawings are merely for facilitating the understanding of the embodiments disclosed in this specification, and the technical idea disclosed in this specification is not limited by the attached drawings, and it must be understood that all modifications, equivalents, and alternatives included in the idea and technical scope of the present invention are included.

[0032] Terms including ordinal numbers such as first, second, etc. can be used to describe various components, but the components are not limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

[0033] When a component is referred to as being "connected" or "attached" to another component, it should be understood that it may be directly connected or attached to the other component, or may be opposite, but there may also be other components in between. On the contrary, when a component is referred to as being "directly connected" or "directly attached" to another component, it should be understood that there are no other components in between.

[0034] Throughout the specification, terms such as "including" or "having" are intended to specify the presence of the features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, and it should not be understood that the presence or addition possibility of one or more other features, numbers, steps, operations, components, parts, or combinations thereof are precluded in advance. Therefore, when a part "includes" a certain component, this means that it can further include other components rather than excluding other components unless there is a contrary description.

[0035] FIG. 1 is a perspective view showing a multilayer capacitor 100 according to an embodiment, FIG. 2 is a cross-sectional view of the multilayer capacitor 100 taken along line I-I' of FIG. 1, and FIG. 3 is an exploded perspective view showing the laminated structure of the internal electrodes in the capacitor body 110 of FIG. 1.

[0036] To clearly explain this embodiment, if directions are defined, the L-axis, W-axis, and T-axis shown in the drawings indicate the length direction, width direction, and thickness direction of the capacitor body 110, respectively. Here, the thickness direction (T-axis direction) may be a direction perpendicular to the broad surface (main surface) of the sheet-shaped component, and as an example, it can be used as the same concept as the lamination direction in which the dielectric layer 111 is laminated. The length direction (L-axis direction) may be a direction extending parallel to the broad surface (main surface) of the sheet-shaped component and substantially perpendicular to the thickness direction (T-axis direction), and as an example, it may be the direction in which the first external electrode 131 and the second external electrode 132 are located on both sides. The width direction (W-axis direction) may be a direction extending parallel to the broad surface (main surface) of the sheet-shaped component and substantially perpendicular to the thickness direction (T-axis direction) and the length direction (L-axis direction), and the length in the length direction (L-axis direction) of the sheet-shaped component may be even longer than the length in the width direction (W-axis direction).

[0037] Referring to FIGS. 1 to 3, the multilayer capacitor 100 according to this embodiment can include a capacitor body 110 and a first external electrode 131 and a second external electrode 132 disposed at both ends facing each other in the length direction (L-axis direction) of the capacitor body 110.

[0038] The capacitor body 110 may be, for example, substantially hexahedral in shape.

[0039] In this embodiment, for convenience of explanation, both surfaces of the capacitor body 110 facing each other in the thickness direction (T-axis direction) are defined as the first surface and the second surface, both surfaces connected to the first surface and the second surface and facing each other in the length direction (L-axis direction) are defined as the third surface and the fourth surface, and both surfaces connected to the first surface and the second surface and connected to the third surface and the fourth surface and facing each other in the width direction (W-axis direction) are defined as the fifth surface and the sixth surface.

[0040] As an example, the first surface, which is the bottom surface, can be the surface facing the mounting direction. Also, the first to sixth surfaces may be flat, but the present embodiment is not limited thereto. For example, the first to sixth surfaces may be curved surfaces convex at the center, and the corners that are the boundaries of each surface may be rounded.

[0041] The shape, dimensions, and number of stacked dielectric layers 111 of the capacitor body 110 are not limited to those shown in the drawings of the present embodiment.

[0042] The capacitor body 110 is formed by firing after stacking a plurality of dielectric layers 111 in the thickness direction (T-axis direction), and includes a first internal electrode layer 121 and a second internal electrode layer 122 that are alternately arranged in the thickness direction (T-axis direction) with the plurality of dielectric layers 111 interposed therebetween.

[0043] At this time, the boundaries between the adjacent dielectric layers 111 of the capacitor body 110 can be integrated to such an extent that it is difficult to confirm without using a scanning electron microscope (SEM).

[0044] Also, the capacitor body 110 can include an active region and cover regions 112 and 113.

[0045] The active region is a portion that contributes to the formation of the capacitance of the multilayer capacitor 100. As an example, the active region may be a region where the first internal electrode layer 121 or the second internal electrode layer 122 stacked along the thickness direction (T-axis direction) overlaps.

[0046] The cover regions 112 and 113 are margins in the thickness direction and can be respectively arranged on the first surface and the second surface sides of the active region in the thickness direction (T-axis direction). Such cover regions 112 and 113 may be formed by stacking a single dielectric layer 111 or two or more dielectric layers 111 on the upper surface and the lower surface of the active region, respectively.

[0047] Further, the capacitor body 110 can further include side cover regions. The side cover regions are margins in the width direction and can be respectively arranged on the fifth and sixth surfaces of the active region in the width direction (W-axis direction). Such side cover regions can be formed by applying a conductive paste layer for forming an internal electrode layer only to a partial region of the surface of the dielectric green sheet when applying the conductive paste layer to the surface of the dielectric green sheet, laminating dielectric green sheets without applying the conductive paste layer to both side surfaces of the surface of the dielectric green sheet, and then firing.

[0048] The cover regions 112 and 113 and the side cover regions serve to prevent damage to the first internal electrode layer 121 and the second internal electrode layer 122 due to physical or chemical stress.

[0049] Internal electrode The first internal electrode 121 and the second internal electrode 122 are electrodes having different polarities from each other, are alternately arranged facing each other along the T-axis direction with the dielectric layer 111 interposed therebetween, and one end of each is exposed through the third and fourth surfaces of the capacitor body 110.

[0050] The first internal electrode 121 and the second internal electrode 122 are electrically insulated from each other by the dielectric layer 111 disposed therebetween.

[0051] The ends of the first internal electrode 121 and the second internal electrode 122 alternately exposed through the third and fourth surfaces of the capacitor body 110 are respectively connected to the first external electrode 131 and the second external electrode 132 and can be electrically connected.

[0052] The internal electrodes 121 and 122 contain zirconium (Zr), and as an example, can contain a conductive metal and zirconium (Zr), and can contain an alloy of the conductive metal and zirconium (Zr).

[0053] Zirconium (Zr) is added in the form of zirconium oxide (ZrO₂) to the conductive paste for the internal electrodes. After the firing process, the internal electrodes 121 and 122 can contain zirconium oxide (ZrO₂), Zr, or a combination thereof.

[0054] Since the melting point of zirconium oxide (ZrO₂) is approximately 1100 °C higher than that of barium titanate (BaTiO₃), which was the previously used co-material, when zirconium oxide is included in the conductive paste for the internal electrodes and fired, the thermal shrinkage delay effect of the internal electrodes is extremely excellent compared to the case of using barium titanate. As a result, the thermal stability of the internal electrodes increases, and the electrode connectivity of the internal electrodes can be greatly improved.

[0055] As an example, the conductive metal can further include metals such as Ni, Cu, Ag, Pd, or Au, and alloys thereof, such as Ag-Pd alloy. As an example, when the conductive metal is Ni, the first internal electrode 121 and the second internal electrode 122 can contain Ni and Zr, and can contain, for example, a Ni-Zr alloy.

[0056] In addition, the first internal electrode 121 and the second internal electrode 122 can also contain dielectric particles of the same composition system as the ceramic material contained in the dielectric layer 111.

[0057] The first internal electrode 121 and the second internal electrode 122 can be formed using a conductive paste containing a conductive metal. As the printing method of the conductive paste, a screen printing method or a gravure printing method can be used.

[0058] In one embodiment, the average content of zirconium (Zr) with respect to the entire internal electrodes 121 and 122 is 0.0005 mol% or more and less than 5.0 mol%.

[0059] As an example, the average content of zirconium (Zr) with respect to the entire internal electrodes 121 and 122 may be 0.0005 mol% or more, or 0.001 mol% or more, and may be less than 5.0 mol%, 2.5 mol% or less, or 1.0 mol% or less.

[0060] As an example, the average content of zirconium (Zr) with respect to the entire internal electrodes 121 and 122 may be 0.0005 mol% or more and 2.5 mol% or less, for example, 0.001 mol% or more and 2.5 mol% or less, or 0.001 mol% or more and 1.0 mol% or less.

[0061] When the average content of zirconium (Zr) in the internal electrodes 121 and 122 is less than 0.0005 mol%, the effect of improving electrode connectivity may be negligible, and when it is 5 mol% or more, the electrical characteristics and reliability of the capacitor may deteriorate.

[0062] FIG. 4 is a TEM image of a partial cross-section of a multilayer capacitor according to an embodiment, and FIGS. 5 and 6 are graphs showing the results of line analysis of the contents of Ti, Ni, and Zr by TEM-EDS according to the positions of the dielectric layer and the internal electrodes.

[0063] Referring to FIGS. 4 to 6, the average content (mol%) of zirconium (Zr) in the internal electrodes 121 and 122 can be measured by the following method.

[0064] First, after placing the multilayer capacitor 100 in an epoxy mixture and curing it, the sides of the capacitor body 110 in the W-axis direction and the T-axis direction are polished to the 1 / 2 point in the L-axis direction, fixed, and maintained in a vacuum atmosphere chamber, and a cross-sectional sample (hereinafter referred to as "cross-sectional sample") cut from the center of the capacitor body 110 in the L-axis direction in the W-axis direction and the T-axis direction is prepared.

[0065] Thereafter, a transmission electron microscope (TEM) image as shown in FIG. 4, which is obtained by observing the cross-sectional sample with a transmission electron microscope (TEM), is prepared.

[0066] Thereafter, the TEM image of the cross-sectional sample is mapped with the Zr component to confirm that Zr can be detected from the cross-sectional sample and to confirm the positions where Zr is distributed.

[0067] Thereafter, line-profile analysis is performed using the EDS (Energy Disperse X-Ray Spectrometer) installed in the transmission electron microscope (TEM, Transmission Electron Microscope) to measure the content according to the positions where Zr is distributed.

[0068] Referring to FIGS. 5 and 6, the Zr present on the internal electrode side and its content can be confirmed. Line-profile analysis is performed at at least two or more points and the arithmetic mean is obtained to derive the average content of Zr contained in the internal electrode.

[0069] As an example, the average thickness of the first internal electrode 121 and the second internal electrode 122 may be 0.1 μm, 0.2 μm or more, or 0.25 μm or more, and may also be 2.0 μm or less, 1 μm or less, 0.5 μm or less.

[0070] The average thickness of the first internal electrodes 121 and 122 can be measured by the following method.

[0071] In the scanning electron microscope (SEM) image of the cross-sectional sample, taking the central point in the L-axis direction or the W-axis direction of the first internal electrode 121 or the second internal electrode 122 as the reference point, the arithmetic mean value of the thicknesses of the first internal electrodes 121 and 122 at 10 points separated from the reference point by a predetermined interval can be obtained to obtain the average thickness of the internal electrode.

[0072] The interval between the 10 points can be adjusted according to the scale of the scanning electron microscope (SEM) image, and may be, for example, an interval of 1 μm or more and 100 μm or less, 1 μm or more and 50 μm or less, or 1 μm or more and 10 μm or less.

[0073] At this time, all 10 points must be located within the first internal electrode 121 or the second internal electrode 122. If all 10 points are not located within the first internal electrode 121 or the second internal electrode 122, the position of the reference point can be changed, or the interval between the 10 points can be adjusted.

[0074] Dielectric layer Zr oxide (ZrO2) added to the conductive paste for the internal electrode diffuses partly in the form of Zr into the dielectric layer 111 through the firing process, and the diffused Zr is mainly contained near the interface of the dielectric layer 111 located close to the internal electrodes 121 and 122.

[0075] Zr diffused near the interface of the dielectric layer 111 can suppress the grain growth of the dielectric crystal grains located near the interface. By reducing the size of the dielectric crystal grains in this way, the interface reliability between the dielectric layer 111 and the internal electrodes 121 and 122 can be increased.

[0076] In addition, the average grain diameter of the dielectric crystal grains contained in the central part of the dielectric layer 111 can be made relatively large, and a multilayer capacitor excellent in electrical characteristics and reliability can be realized.

[0077] FIG. 7 is a schematic diagram showing a partial cross section of a multilayer capacitor 100 according to an embodiment.

[0078] Referring to FIG. 7, the dielectric layer 111 includes a plurality of dielectric crystal grains 1111.

[0079] The dielectric crystal grains 1111 include a main component and a sub-component.

[0080] The main component is the base material of the dielectric, has a high dielectric constant, and contributes to the formation of the dielectric constant of the multilayer capacitor 100.

[0081] The main component is Ba m TiO3 (0.995 ≦ m ≦ 1.010), (Ba 1-X Ca x ) m (Ti 1-y Zry )O3 (0.995 ≤ m ≤ 1.010, 0 ≤ x ≤ 0.10, 0 < y ≤ 0.20), Ba m (Ti 1-x Zr x )O3 (0.995 ≤ m ≤ 1.010, x ≤ 0.10), (Ba 1-X Ca x ) m (Ti 1-y Sn y )O3 (0.995 ≤ m ≤ 1.010, 0 ≤ x ≤ 0.10, 0 < y ≤ 0.20), or it may be a dielectric material containing a combination thereof.

[0082] As a specific example, the main component is (Ba 1-X Ca x ) m (Ti 1-y Zr y )O3 (0.995 ≤ m ≤ 1.010, 0 ≤ x ≤ 0.10, 0 < y ≤ 0.20), Ba m (Ti 1-x Zr x )O3 (0.995 ≤ m ≤ 1.010, x ≤ 0.10), or it can contain a combination thereof.

[0083] As an example, the main component can include BaTiO3, Ba(Ti,Zr)O3, Ba(Ti,Sn)O3, (Ba,Ca)TiO3, (Ba,Ca)(Ti,Zr)O3, (Ba,Ca)(Ti,Sn)O3, (Ba,Sr)TiO3, (Ba,Sr)(Ti,Zr)O3, (Ba,Sr)(Ti,Sn)O3, or a combination thereof.

[0084] The secondary components can include zirconium (Zr), manganese (Mn), chromium (Cr), silicon (Si), aluminum (Al), magnesium (Mg), tin (Sn), antimony (Sb), hafnium (Hf), germanium (Ge), gallium (Ga), indium (In), lanthanum (La), yttrium (Y), actinium (Ac), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), or combinations thereof.

[0085] The dielectric layer 111 may further include a ceramic additive, an organic solvent, a binder, a dispersant, or combinations thereof.

[0086] Referring to FIG. 7, the dielectric layer 111 can include the central portion of the dielectric layer 111 and the interface portion of the dielectric layer 111 that is located on the surface of the central portion of the dielectric layer 111 and contacts the internal electrodes 121 and 122.

[0087] The central portion of the dielectric layer 111 can mean the intermediate point between a point on one side surface of any one dielectric layer 111 and a point on the other side surface of the dielectric layer 111 that is located at the shortest distance from the said point in the cross-section obtained by cutting in the W-axis direction and the T-axis direction from the center in the L-axis direction of the capacitor body 110. Also, it can mean not only the intermediate point but also the region within ±30% in the T-axis direction with respect to the intermediate point.

[0088] The interface portion of the dielectric layer 111 can mean the point that is 100 nm separated in the T-axis direction from the interface arranged between the dielectric layer 111 and the internal electrodes 121 and 122 in the region other than the central portion of the dielectric layer 111, toward the central portion of the dielectric layer 111. Also, it can mean not only the point but also the region within ±30% in the T-axis direction with respect to the point.

[0089] Referring to FIGS. 5 and 6, the interface portion of the dielectric layer 111 contains a relatively large amount of Zr diffused from the internal electrodes, and the Zr content decreases toward the center of the dielectric layer 111.

[0090] In one embodiment, the average content of zirconium (Zr) with respect to the entire interface portion of the dielectric layer 111 may be 0.001 mol% or more and 10.0 mol% or less, for example, 0.01 mol% or more and 10.0 mol% or less, 0.1 mol% or more and 10.0 mol% or less, or 0.1 mol% or more and 5.0 mol% or less.

[0091] When the average content of zirconium (Zr) with respect to the entire interface portion of the dielectric layer 111 satisfies the above numerical range, a multilayer capacitor with increased interface reliability can be realized.

[0092] In one embodiment, the average content of zirconium (Zr) with respect to the entire central portion of the dielectric layer 111 may be 0 mol% or more and 2.0 mol% or less, for example, 0 mol% or more and 1.0 mol% or less, or 0 mol% or more and 0.5 mol% or less.

[0093] When the average content of zirconium (Zr) with respect to the entire central portion of the dielectric layer 111 satisfies the above numerical range, a multilayer capacitor with excellent electrical characteristics and reliability can be realized.

[0094] The average content of zirconium (Zr) in the interface portion of the dielectric layer 111 and the central portion of the dielectric layer 111 can be measured by the following method.

[0095] Select five or more arbitrary dielectric layers 111 in the TEM image of the cross-sectional sample, and select five equally spaced points corresponding to the central portion of the dielectric layer 111 and the interface portion of the dielectric layer 111, respectively. Perform Line-profile quantitative analysis as shown in FIGS. 5 and 6 at each selected point to measure the Zr content, calculate the arithmetic mean value of the measured values, and obtain the average content of zirconium (Zr) in the interface portion of the dielectric layer 111 and the central portion of the dielectric layer 111.

[0096] Referring to FIG. 7, the dielectric crystal grains 1111 can include first dielectric crystal grains 1111a located at the interface portion of the dielectric layer 111 and second dielectric crystal grains 1111b located at the central portion of the dielectric layer 111.

[0097] In one embodiment, the average particle size of the first dielectric crystal grains may be smaller than the average particle size of the second dielectric crystal grains.

[0098] In one embodiment, the average particle size of the first dielectric crystal grains 1111a may be 50 nm or more and 200 nm or less, for example, 50 nm or more and 150 nm or less, or 50 nm or more and 100 nm or less.

[0099] In one embodiment, the average particle size of the second dielectric crystal grains 1111b may be 150 nm or more and 500 nm or less, for example, 200 nm or more and 500 nm or less, or 200 nm or more and 400 nm or less.

[0100] The method for measuring the average particle sizes of the first dielectric crystal grains 1111a and the second dielectric crystal grains 1111b is as follows.

[0101] First, by a method such as binarizing the TEM image or SEM image of the cross-sectional sample, the boundary (grain boundary) of the dielectric crystal grains can be confirmed by distinguishing the bright and dark portions, and the morphologies of the first dielectric crystal grains 1111a and the second dielectric crystal grains 1111b can be confirmed.

[0102] Five equally spaced points corresponding to the central portion of the dielectric layer 111 and the interface portion of the dielectric layer 111 are respectively selected in the TEM image or SEM image, and three or more dielectric crystal grains observed at the selected points are selected to measure the particle sizes, and the arithmetic mean value is derived to measure the average particle sizes of the first dielectric crystal grains 1111a and the second dielectric crystal grains 1111b.

[0103] As an example, the average thickness of the dielectric layer 111 may be 0.1 μm or more, 0.5 μm or more, or 1.0 μm or more, and may also be 5.0 μm or less, or 2.5 μm or less.

[0104] The average thickness of the dielectric layer 111 can be measured by the following method.

[0105] First, prepare a scanning electron microscope (SEM) image obtained by observing a cross-sectional sample with a scanning electron microscope.

[0106] In the scanning electron microscope (SEM) image of the cross-sectional sample, taking the central point in the L-axis direction or the W-axis direction of the dielectric layer 111 as a reference point, the arithmetic mean value of the thicknesses of the dielectric layer 111 at 10 points separated from the reference point at a predetermined interval can be obtained and used as the average thickness of the dielectric layer 111.

[0107] The interval between the 10 points can be adjusted according to the scale of the scanning electron microscope (SEM) image. For example, it may be an interval of 1 μm or more and 100 μm or less, 1 μm or more and 50 μm or less, or 1 μm or more and 10 μm or less.

[0108] At this time, all 10 points must be located within the dielectric layer 111. If all 10 points are not located within the dielectric layer 111, the position of the reference point can be changed, or the interval between the 10 points can be adjusted.

[0109] External electrode The first external electrode 131 and the second external electrode 132 are provided with voltages of different polarities and are respectively connected to the exposed portions of the first internal electrode 121 and the second internal electrode 122 and can be electrically connected.

[0110] With the above configuration, when a predetermined voltage is applied to the first external electrode 131 and the second external electrode 132, charges are accumulated between the first internal electrode 121 and the second internal electrode 122 that face each other. At this time, the capacitance of the multilayer capacitor 100 becomes proportional to the overlapping area of the first internal electrode 121 and the second internal electrode 122 that overlap each other along the T-axis direction in the active region.

[0111] The first external electrode 131 and the second external electrode 132 are respectively disposed on the third surface and the fourth surface of the capacitor body 110 and include a first connection portion and a second connection portion connected to the first internal electrode 121 and the second internal electrode 122, the third surface and the fourth surface of the capacitor body 110, and a first band portion and a second band portion disposed at corners where the first surface and the second surface or the fifth surface and the sixth surface are in contact.

[0112] The first band portion and the second band portion are respectively extended from the first connection portion and the second connection portion to a part of the first surface and the second surface or the fifth surface and the sixth surface of the capacitor body 110. The first band portion and the second band portion can serve to improve the adhesion strength of the first external electrode 131 and the second external electrode 132.

[0113] As an example, the first external electrode 131 and the second external electrode 132 can each include a sintered metal layer in contact with the capacitor body 110, a conductive resin layer disposed to cover the sintered metal layer, and a plating layer disposed to cover the conductive resin layer.

[0114] The sintered metal layer can include a conductive metal and glass.

[0115] As an example, the sintered metal layer can include copper (Cu), nickel (Ni), silver (Ag), palladium (Pd), gold (Au), platinum (Pt), tin (Sn), tungsten (W), titanium (Ti), lead (Pb), alloys thereof, or combinations thereof as the conductive metal. For example, copper (Cu) can include a copper (Cu) alloy. When the conductive metal includes copper, the metal other than copper may be included in an amount of 5 mol or less per 100 mol of copper.

[0116] As an example, the sintered metal layer can further include glass. In this case, the sintered metal layer can include a composition in which an oxide is mixed as the glass. For example, it may be one or more selected from the group consisting of silicon oxide, boron oxide, aluminum oxide, transition metal oxide, alkali metal oxide, and alkaline earth metal oxide. The transition metal is selected from the group consisting of zinc (Zn), titanium (Ti), copper (Cu), vanadium (V), manganese (Mn), iron (Fe), and nickel (Ni). The alkali metal is selected from the group consisting of lithium (Li), sodium (Na), and potassium (K). The alkaline earth metal may be one or more selected from the group consisting of magnesium (Mg), calcium (Ca), strontium (Sr), and barium (Ba).

[0117] Optionally, the conductive resin layer is formed on the sintered metal layer and can be formed, for example, in a form that completely covers the sintered metal layer. On the other hand, the first external electrode 131 and the second external electrode 132 may not include the sintered metal layer. In this case, the conductive resin layer can be in direct contact with the capacitor body 110.

[0118] The conductive resin layer extends to the first and second surfaces or the fifth and sixth surfaces of the capacitor body 110. The length of the region (i.e., the band portion) where the conductive resin layer extends and is disposed on the first and second surfaces or the fifth and sixth surfaces of the capacitor body 110 may be longer than the length of the region (i.e., the band portion) where the sintered metal layer extends and is disposed on the first and second surfaces or the fifth and sixth surfaces of the capacitor body 110. That is, the conductive resin layer is formed on the sintered metal layer and can be formed in a form that completely covers the sintered metal layer.

[0119] The conductive resin layer contains a resin and a conductive metal.

[0120] The resin contained in the conductive resin layer has bonding properties and shock absorption properties, and is not particularly limited as long as it can be mixed with the conductive metal powder to form a paste. For example, it can include a phenolic resin, an acrylic resin, a silicone resin, an epoxy resin, or a polyimide resin.

[0121] The conductive metal contained in the conductive resin layer serves to be electrically connected to the first internal electrode 121 and the second internal electrode 122 or the sintered metal layer.

[0122] The conductive metal contained in the conductive resin layer can have a spherical shape, a flake shape, or a combination of these forms. That is, the conductive metal may consist only of a flake shape or only of a spherical shape, or may be a form in which the flake shape and the spherical shape are mixed.

[0123] Here, the spherical shape can also include a shape that is not a perfect sphere. For example, it can include a shape in which the length ratio of the major axis to the minor axis (major axis / minor axis) is 1.45 or less. The flake-shaped powder means a powder having a flat and elongated shape, and is not particularly limited. For example, the length ratio of the major axis to the minor axis (major axis / minor axis) may be 1.95 or more.

[0124] The first external electrode 131 and the second external electrode 132 can further include a plating layer disposed outside the conductive resin layer.

[0125] The plating layer can include a single metal such as nickel (Ni), copper (Cu), tin (Sn), palladium (Pd), platinum (Pt), gold (Au), silver (Ag), tungsten (W), titanium (Ti), or lead (Pb), or an alloy thereof. As an example, the plating layer may be a nickel (Ni) plating layer or a tin (Sn) plating layer, or may be in a form where a nickel (Ni) plating layer and a tin (Sn) plating layer are laminated in sequence, or may be in a form where a tin (Sn) plating layer, a nickel (Ni) plating layer, and a tin (Sn) plating layer are laminated in sequence. Also, the plating layer can include a plurality of nickel (Ni) plating layers and / or a plurality of tin (Sn) plating layers.

[0126] The plating layer can improve the mountability with the substrate of the multilayer capacitor 100, the structural reliability, the durability against the outside, the heat resistance, and the equivalent series resistance (ESR).

[0127] Manufacturing method of multilayer capacitor The manufacturing method of the multilayer capacitor according to another embodiment includes a step of manufacturing a capacitor body including a dielectric layer and internal electrodes, and a step of forming external electrodes on the outside of the capacitor body.

[0128] First, the manufacturing of the capacitor body will be described.

[0129] In the manufacturing process of the capacitor body, a dielectric paste that becomes a dielectric layer after firing and a conductive paste that becomes internal electrodes after firing are prepared.

[0130] The dielectric paste is manufactured, for example, in the following manner. Dielectric powder is uniformly mixed by means such as wet mixing, dried, and then heat-treated under predetermined conditions to obtain plastic powder. An organic vehicle or an aqueous vehicle is added to the obtained plastic powder and kneaded to prepare a dielectric paste.

[0131] A dielectric green sheet is obtained by forming the obtained dielectric paste into a sheet by a technique such as the doctor blade method. The dielectric paste may contain additives selected from various dispersants, plasticizers, dielectrics, sub-component compounds, or glass, etc., if necessary.

[0132] The conductive paste for the internal electrode is prepared by kneading conductive powder made of a conductive metal or its alloy with a binder and a solvent. As an example, the conductive paste for the internal electrode can be prepared by kneading zirconium oxide. The conductive paste for the internal electrode may contain ceramic powder (for example, barium titanate powder) as a co-material, if necessary. The co-material can play a role in suppressing the sintering of the conductive powder during the firing process.

[0133] The conductive paste for the internal electrode is applied in a predetermined pattern on the surface of the dielectric green sheet by various printing methods such as screen printing or a transfer method. Then, after laminating the dielectric green sheets with the internal electrode pattern formed thereon in multiple layers, a dielectric green sheet laminate is obtained by pressing in the lamination direction. At this time, on the upper and lower surfaces of the dielectric green sheet laminate in the lamination direction, the dielectric green sheet and the internal electrode pattern can be laminated so that the dielectric green sheet is positioned.

[0134] Optionally, the obtained dielectric green sheet laminate can be cut into a predetermined size by dicing or the like.

[0135] Also, the dielectric green sheet laminate can be solidified and dried to remove plasticizers, etc., if necessary, and can be barrel-polished using a horizontal centrifugal barrel polishing machine or the like after solidification and drying. In barrel polishing, the dielectric green sheet laminate is put into a barrel container together with media and a polishing liquid, and by applying rotational motion, vibration, etc. to the barrel container, unnecessary parts such as burrs generated during cutting can be polished. Also, after barrel polishing, the dielectric green sheet laminate can be washed with a cleaning liquid such as water and dried.

[0136] The dielectric green sheet laminate is subjected to a debinding process and a firing process to obtain a capacitor body.

[0137] The conditions of the debinding process can be appropriately adjusted according to the main component composition of the dielectric layer and the main component composition of the internal electrode. For example, the heating rate during the debinding process may be 5°C / hour or more and 300°C / hour or less, the holding temperature may be 180°C or more and 400°C or less, and the temperature holding time may be 0.5 hour or more and 24 hours or less. The debinding atmosphere may be air or a reducing atmosphere.

[0138] The conditions of the firing process can be appropriately adjusted according to the main component composition of the dielectric layer and the main component composition of the internal electrode. For example, the temperature during firing may be 1200°C or more and 1350°C or less, or 1220°C or more and 1300°C or less, and the time may be 0.5 hour or more and 8 hours or less, or 1 hour or more and 3 hours or less. The firing atmosphere may be a reducing atmosphere, for example, an atmosphere in which a mixed gas of nitrogen gas (N2) and hydrogen gas (H2) is humidified. When the internal electrode contains nickel (Ni) or a nickel (Ni) alloy, the oxygen partial pressure in the firing atmosphere is 1.0×10 -14 MPa or more and 1.0×10 -10 MPa or less.

[0139] After the firing process, annealing can be carried out if necessary. Annealing is a process for re-oxidizing the dielectric layer, and when the firing process is carried out in a reducing atmosphere, annealing can be carried out. The conditions of the annealing process can also be appropriately adjusted according to the main component composition of the dielectric layer, etc. For example, the temperature during annealing may be 950°C or more and 1150°C or less, the time may be 0 hour or more and 20 hours or less, and the heating rate may be 50°C / hour or more and 500°C / hour or less. The annealing atmosphere may be a humidified nitrogen gas (N2) atmosphere, and the oxygen partial pressure may be 1.0×10 -9 MPa or more and 1.0×10 -5 MPa or less.

[0140] For humidifying nitrogen gas, mixed gas, etc. in the debinding process, firing process, or annealing process, for example, a wetter can be used. In this case, the water temperature may be 5°C or higher and 75°C or lower. The debinding process, firing process, and annealing process can be performed continuously or independently.

[0141] Optionally, surface treatment such as sandblasting, laser irradiation, or barrel polishing can be performed on the third and fourth surfaces of the obtained capacitor body. By performing such surface treatment, the ends of the first internal electrode and the second internal electrode are exposed on the outermost surfaces of the third and fourth surfaces, thereby improving the electrical connection between the first external electrode and the second external electrode and the first internal electrode and the second internal electrode, and making it easier to form an alloy portion.

[0142] Next, a paste for forming a sintered metal layer can be applied to the outer surface of the obtained capacitor body and then sintered to form a sintered metal layer.

[0143] The paste for forming a sintered metal layer can contain a conductive metal and glass. Since the description of the conductive metal and glass is as described above, repeated explanations are omitted. Also, the paste for forming a sintered metal layer can optionally contain sub-components such as a binder, a solvent, a dispersant, a plasticizer, or an oxide powder. For example, as the binder, ethyl cellulose, acrylic, or butyral can be used, and as the solvent, an organic solvent such as terpineol, butyl carbitol, alcohol, methyl ethyl ketone, acetone, or toluene, or an aqueous solvent can be used.

[0144] As a method for applying the paste for forming the sintered metal layer to the outer surface of the capacitor body, dipping method, various printing methods such as screen printing, coating method using a dispenser or the like, or spraying method using a spray can be used. The paste for forming the sintered metal layer is applied at least to the third surface and the fourth surface of the capacitor body, and can also be applied to a part of the first surface, the second surface, the fifth surface, or the sixth surface where the band portions of the first external electrode and the second external electrode are selectively formed.

[0145] Thereafter, the capacitor body coated with the paste for forming the sintered metal layer is dried and sintered at a temperature of 700 ° C or higher and 1000 ° C or lower for 0.1 hour or more and 3 hours or less to form a sintered metal layer.

[0146] Optionally, a conductive resin layer can be formed by applying a paste for forming a conductive resin layer to the outer surface of the obtained capacitor body and then curing it.

[0147] The paste for forming the conductive resin layer can contain a resin and optionally a conductive metal or a non-conductive filler. Since the description of the conductive metal and the resin is the same as described above, the repeated description will be omitted. Further, the paste for forming the conductive resin layer can optionally contain sub-components such as a binder, a solvent, a dispersant, a plasticizer, or an oxide powder. For example, as the binder, ethyl cellulose, acrylic, or butyral can be used, and as the solvent, an organic solvent such as terpineol, butyl carbitol, alcohol, methyl ethyl ketone, acetone, or toluene, or an aqueous solvent can be used.

[0148] As an example, the method for forming the conductive resin layer can be to dip the capacitor body 110 into the paste for forming the conductive resin layer and then cure it, or to print the paste for forming the conductive resin layer on the surface of the capacitor body 110 by a screen printing method or a gravure printing method, or to apply the paste for forming the conductive resin layer on the surface of the capacitor body 110 and then cure it to form.

[0149] Next, a plating layer is formed outside the conductive resin layer.

[0150] As an example, the plating layer can be formed by a plating method, and can also be formed by sputtering or electroplating.

[0151] Specific embodiments of the invention are presented below. However, the embodiments described below are merely for specifically exemplifying or explaining the invention, and the scope of the invention should not be limited thereby.

[0152] [Embodiment] (Reference Example) ZrO2 is added to the conductive paste containing Ni so that the amount of Zr is as shown in Table 1 below, and the conductive paste for forming an internal electrode according to Reference Examples 1 to 4 is manufactured. (Experimental Example) Samples obtained by processing the conductive pastes manufactured in Reference Examples 1 to 4 into a powder form are manufactured, and the heat shrinkage rate (%) due to temperature is measured while changing the temperature from 0 °C to 1000 °C, and is shown in Table 1 and FIG. 8.

[0153] Specifically, it is measured using a TMA (Thermo Mechanical Analyzer), and 3% H2 gas is measured at a heating rate of 10 K / min.

[0154]

Table 1

[0155] Referring to Table 1, it can be confirmed that in the case of Reference Examples 2 to 4 containing an appropriate amount of Zr as compared with Reference Example 1 not containing Zr, the temperatures at initial shrinkage, 5% shrinkage, and 15% shrinkage are much higher. Also, referring to FIG. 8, it can be confirmed that the heat shrinkage rates of Reference Examples 2 to 4 are even lower at the same temperature.

[0156] Finally, it can be confirmed that in the case of Reference Examples 2 to 4 containing an appropriate amount of Zr, the thermal stability is higher than that of Reference Example 1.

[0157] (Example); Manufacturing of multilayer capacitor Example 1 Prepare a slurry for a dielectric containing BaTiO3, and use an on-roll coater with a head ejection method to produce a dielectric green sheet from the slurry for the dielectric.

[0158] Next, weigh and mix Ni and Zr so that the content of Zr with respect to the entire internal electrode becomes 0.001 mol%, and produce a conductive paste for the internal electrode.

[0159] Print the conductive paste on the surface of the dielectric green sheet, and laminate and press the dielectric green sheet (width × length × height = 3.2 mm × 2.5 mm × 2.5 mm) with the formed conductive paste layer to produce a dielectric green sheet laminate.

[0160] Subject the dielectric green sheet laminate to a plasticizing process in a nitrogen atmosphere at 400°C or lower, and then fire it under the conditions of a firing temperature of 1300°C or lower and a hydrogen concentration of 1.0% H2 or lower to produce a multilayer capacitor according to Example 1.

[0161] Examples 2 to 3 and Comparative Examples 1 to 3 Manufacture multilayer capacitors of Examples 2 to 3 and Comparative Examples 1 to 3 in the same manner as in Example 1, except that the content of Zr with respect to the entire internal electrode is adjusted as shown in Table 2 below.

[0162] (Evaluation Example) Evaluation Example 1: Evaluation of electrode connectivity Evaluate the electrode connectivity of the multilayer capacitors manufactured in Examples 1 to 3 and Comparative Examples 1 to 3.

[0163] First, prepare four laminated capacitors each, place them in an epoxy mixture and cure them. After that, polish the sides of the capacitor body 110 in the W-axis direction and the T-axis direction to the 1 / 2 point in the L-axis direction, maintain them in a vacuum atmosphere chamber after fixing, and prepare a cross-sectional sample cut from the center of the capacitor body 110 in the L-axis direction in the W-axis direction and the T-axis direction. Next, observe the cross-sectional sample with a transmission electron microscope (TEM) (observe at a magnification of 200) to prepare a TEM image.

[0164] Next, select an arbitrary internal electrode, draw a virtual line in the L-axis direction, and then measure the ratio of the length of the unbroken internal electrode to the total length of the internal electrode.

[0165] Taking the ratio of the length measured in Comparative Example 1 as the reference value 1, describe the relative values of other Examples and Comparative Examples.

[0166] Evaluation Example 2: Evaluation of electrical characteristics (BDV, capacitance), reliability (MTTF) Evaluate the breakdown voltage (BDV), capacitance, and MTTF of the laminated capacitors manufactured in Examples 1 to 3 and Comparative Examples 1 to 3, and show the results in Table 2.

[0167] To measure the BDV, prepare 50 laminated capacitors each, apply a voltage in a sweep manner from 0 V to 1.00000 V up to 1100 V using a Keithley measuring instrument model 2410, and measure the voltage value at the moment when the current value reaches 20 mA as the breakdown voltage value. The breakdown voltage is measured in a silicon oil bath. Taking the BDV of Comparative Example 1 as the reference value 1, describe the relative values of other Examples and Comparative Examples.

[0168] The capacitance is measured using an LCR meter under the conditions of 1 kHz and AC 0.5 V. In Table 2, taking the capacitance of Comparative Example 1 as the reference value 1, describe the relative values of other Examples and Comparative Examples.

[0169] The MTTF (Mean Time To Failure) value is measured by performing a high-temperature load test on 400 samples for each of the above-described examples and comparative examples under the conditions of 125° C. and 8V. At this time, the time when the insulation resistance becomes 10 kΩ or less is defined as the fixed time, and the relative values of the other examples and comparative examples are described in Table 2 with the MTTF value of Comparative Example 1 as the reference value 1.

[0170]

Table 2

[0171] Referring to Table 2, in the case of Examples 1 to 3, it can be confirmed that as the Zr content in the internal electrode increases from 0.001 mol % to 1 mol %, the electrode connectivity increases due to the internal electrode shrinkage delay effect, and thereby the capacitances both increase.

[0172] However, in the case of Comparative Example 2, it can be confirmed that excessive Zr diffused into the dielectric layer, suppressing the grain growth of the dielectric crystal grains, and the electrode connectivity and capacitance decreased as compared with Comparative Example 1.

[0173] Also, in the case of Examples 1 to 3, it can be confirmed that the BDV (Break Down Voltage) and MTTF (reliability) increased due to the increased interface reliability between the dielectric layer and the internal electrode.

[0174] However, in the case of Comparative Example 3 containing an excessive amount of Zr, it can be confirmed that the BDV and MTTF decreased as compared with Comparative Example 1.

[0175] Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications can be made and implemented within the scope of the claims, the detailed description of the invention, and the attached drawings, and it is natural that these also belong to the scope of the present invention.

Explanation of Reference Numerals

[0176] 100: Multilayer capacitor 110: Capacitor body 111: Dielectric layer 1111: Dielectric crystal grains 1111a: First dielectric crystal grains 1111b: Second dielectric crystal grains 112, 113: Cover region 121: First internal electrode 122: Second internal electrode 131: First external electrode 132: Second external electrode

Claims

1. A capacitor body including a dielectric layer and internal electrodes, and including external electrodes disposed outside the capacitor body, wherein the internal electrodes and the dielectric layer contain zirconium (Zr), and a multilayer capacitor in which an average content of the zirconium (Zr) with respect to the entire internal electrodes is 0.0005 mol% or more and less than 5.0 mol%.

2. The multilayer capacitor according to claim 1, wherein the internal electrodes contain a conductive metal and zirconium (Zr).

3. The dielectric layer includes a main component and a sub-component, The main component is (Ba １－Ｘ Ca ｘ )) ｍ (Ti １－ｙ Zr ｙ )O ３ (0.995 ≤ m ≤ 1.010, 0 ≤ x ≤ 0.10, 0 < y ≤ 0.20), Ba ｍ (Ti １－ｘ Zr ｘ )O ３ (0.995 ≤ m ≤ 1.010, x ≤ 0.10), or a combination thereof, the multilayer capacitor according to claim 1.

4. The multilayer capacitor according to claim 1, wherein an average content of the zirconium (Zr) with respect to the entire internal electrodes is 0.001 mol% or more and 1.0 mol% or less.

5. The dielectric layer includes a central portion of the dielectric layer and an interface portion of the dielectric layer located on a surface of the central portion of the dielectric layer and in contact with the internal electrodes, wherein an average content of zirconium (Zr) with respect to the entire interface portion of the dielectric layer is 0.001 mol% or more and 10.0 mol% or less, and an average content of zirconium (Zr) with respect to the entire central portion of the dielectric layer is 0 mol% or more and 2.0 mol% or less, the multilayer capacitor according to claim 1.

6. The dielectric layer includes a plurality of dielectric crystal grains, wherein the dielectric crystal grains include first dielectric crystal grains located in the interface portion of the dielectric layer and second dielectric crystal grains located in the central portion of the dielectric layer, and the multilayer capacitor according to claim 5, wherein an average particle diameter of the first dielectric crystal grains is smaller than an average particle diameter of the second dielectric crystal grains.

7. The multilayer capacitor according to claim 6, wherein the average particle diameter of the first dielectric crystal grains is 50 nm or more and 200 nm or less, and the average particle diameter of the second dielectric crystal grains is 150 nm or more and 500 nm or less.

8. The multilayer capacitor according to claim 1, wherein an average thickness of the dielectric layer is 0.1 µm or more and 5 µm or less.

9. The multilayer capacitor according to claim 1, wherein an average thickness of the internal electrodes is 0.1 µm or more and 2 µm or less.

10. A capacitor body including a dielectric layer and internal electrodes, and including external electrodes disposed outside the capacitor body, wherein the internal electrodes contain a conductive metal and zirconium (Zr), The dielectric layer is (Ba １－Ｘ Ca ｘ ). ｍ (Ti １－ｙ Zr ｙ )O ３ (0.995 ≤ m ≤ 1.010, 0 ≤ x ≤ 0.10, 0 < y ≤ 0.20), Ba ｍ (Ti １－ｘ Zr ｘ )O ３ (0.995 ≤ m ≤ 1.010, x ≤ 0.10), or combinations thereof, and a multilayer capacitor in which an average content of the zirconium (Zr) with respect to the entire internal electrodes is 0.0005 mol% or more and less than 5.0 mol%.

11. The laminated capacitor according to claim 10, wherein an average content of the zirconium (Zr) with respect to the entire internal electrode is 0.001 mol% or more and 1.0 mol% or less.

12. The dielectric layer includes a central portion of the dielectric layer and an interface portion of the dielectric layer that is located on a surface of the central portion of the dielectric layer and contacts the internal electrode. An average content of zirconium (Zr) with respect to the entire interface portion of the dielectric layer is 0.001 mol% or more and 10.0 mol% or less. The laminated capacitor according to claim 10, wherein an average content of zirconium (Zr) with respect to the entire central portion of the dielectric layer is 0 mol% or more and 2.0 mol% or less.

13. The dielectric layer includes a plurality of dielectric crystal grains. The dielectric crystal grains include first dielectric crystal grains located at the interface portion of the dielectric layer and second dielectric crystal grains located at the central portion of the dielectric layer. The laminated capacitor according to claim 12, wherein an average particle diameter of the first dielectric crystal grains is smaller than an average particle diameter of the second dielectric crystal grains.

14. The average particle diameter of the first dielectric crystal grains is 50 nm or more and 200 nm or less. The laminated capacitor according to claim 13, wherein the average particle diameter of the second dielectric crystal grains is 150 nm or more and 500 nm or less.

15. The laminated capacitor according to claim 10, wherein an average thickness of the dielectric layer is 0.1 μm or more and 5 μm or less.

16. The laminated capacitor according to claim 10, wherein an average thickness of the internal electrode is 0.1 μm or more and 2 μm or less.

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