Multilayer ceramic capacitor and manufacturing method thereof

Abstract

To provide an excellent multilayer ceramic capacitor having improved DC-bias characteristics and reliability, and a manufacturing method thereof.SOLUTION: A multilayer ceramic capacitor according to an embodiment includes: a capacitor body including a dielectric layer 111 and internal electrode layers 121 and 122; and external electrodes 131 and 132 disposed outside the capacitor body. The dielectric layer includes at least one dielectric grain, and the dielectric grain includes a barium titanate-based primary component including barium and titanium, and a secondary component. The secondary component includes: as a first secondary component, samarium; and, as a second secondary component, lanthanum, cerium, praseodymium, neodymium, promethium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, or a combination thereof. The second secondary component is included in an amount ranging from 1.2 atom % to 2.0 atom % based on 100 atom % of titanium.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to a multilayer ceramic capacitor and a method for manufacturing the same.

Background Art

[0002] Examples of electronic components using ceramic materials include capacitors, inductors, piezoelectric elements, varistors, or thermistors. Among such ceramic electronic components, a multilayer ceramic capacitor (MLCC) can be used in various electronic devices due to its advantages of being small in size, having a high capacitance guaranteed, and being easy to mount.

[0003] For example, a multilayer ceramic capacitor (MLCC) can be used as a chip-shaped capacitor mounted on the substrates of various electronic products such as video devices such as liquid crystal displays (LCDs), plasma display panels (PDPs), organic light-emitting diodes (OLEDs), computers, personal mobile terminals, and smartphones, to perform the role of charging or discharging electricity.

[0004] Recently, as MLCCs are becoming more highly integrated, they are becoming thinner and thinner, and ensuring high reliability under a thin layer design is required.

Summary of the Invention

Problems to be Solved by the Invention

[0005] One embodiment provides an excellent multilayer ceramic capacitor with improved DC-bias characteristics and reliability.

[0006] Another embodiment provides a method for manufacturing the multilayer ceramic capacitor.

Means for Solving the Problems

[0007] One embodiment includes a capacitor body including a dielectric layer and an internal electrode layer, and an external electrode disposed outside the capacitor body. The dielectric layer includes at least one dielectric grain. The dielectric grain includes a barium titanate-based main component containing barium (Ba) and titanium (Ti), and a sub-component. The sub-component includes samarium (Sm) as a first sub-component and a second sub-component. The second sub-component includes lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), or a combination thereof. The second sub-component is included at 1.2 atomic % to 2.0 atomic % with respect to 100 atomic % of the titanium (Ti), and provides a multilayer ceramic capacitor.

[0008] The second sub-component can include the terbium (Tb), the dysprosium (Dy), or a combination thereof.

[0009] The dielectric grain includes a core and a shell surrounding at least a part of the core. The second sub-component is included in the core and the shell, and the atomic % of the second sub-component included in the shell may be higher than the atomic % of the second sub-component included in the core.

[0010] The atomic ratio of the second sub-component included in the shell to the second sub-component included in the core may be 2 to 8.

[0011] The samarium (Sm) may be included at 0.01 atomic % to 1.2 atomic % with respect to 100 atomic % of the titanium (Ti).

[0012] The dielectric crystal grains include a core and a shell surrounding at least a part of the core, the samarium (Sm) is included in the core and the shell, and the atomic percentage of samarium (Sm) included in the shell may be higher than the atomic percentage of samarium (Sm) included in the core.

[0013] The atomic ratio of samarium (Sm) included in the shell to samarium (Sm) included in the core may be 1.2 to 2.5.

[0014] The sub-component may further include a third sub-component including aluminum (Al), silicon (Si), magnesium (Mg), manganese (Mn), or a combination thereof.

[0015] The third sub-component may be included in an amount of 0.1 atomic% to 2.5 atomic% with respect to 100 atomic% of the titanium (Ti).

[0016] The third sub-component may include the aluminum (Al) and the silicon (Si).

[0017] The atomic ratio of samarium (Sm) to the total of the aluminum (Al) and the silicon (Si) may be 0.01 to 0.7.

[0018] The diameter of the dielectric crystal grains may be 100 nm to 500 nm.

[0019] Another embodiment includes the steps of: manufacturing a dielectric slurry by mixing barium titanate-based main component powder, a samarium (Sm)-containing compound, and sub-component powder containing a second sub-component compound; manufacturing a dielectric green sheet using the dielectric slurry and forming a conductive paste layer on the surface of the dielectric green sheet; manufacturing a dielectric green sheet laminate by laminating the dielectric green sheets with the conductive paste layer formed thereon; firing the dielectric green sheet laminate to manufacture a capacitor body including a dielectric layer and an internal electrode layer; and forming an external electrode on one surface of the capacitor body. The second sub-component compound includes a lanthanum (La)-containing compound, a cerium (Ce)-containing compound, a praseodymium (Pr)-containing compound, a neodymium (Nd)-containing compound, a promethium (Pm)-containing compound, a europium (Eu)-containing compound, a gadolinium (Gd)-containing compound, a terbium (Tb)-containing compound, a dysprosium (Dy)-containing compound, a holmium (Ho)-containing compound, an erbium (Er)-containing compound, a thulium (Tm)-containing compound, a ytterbium (Yb)-containing compound, a lutetium (Lu)-containing compound, or a combination thereof, and the second sub-component compound is included in an amount of 1.2 to 2.0 mole parts with respect to 100 mole parts of the barium titanate-based main component powder. A method for manufacturing a multilayer ceramic capacitor is provided.

[0020] The second sub-component compound may include the terbium (Tb)-containing compound, the dysprosium (Dy)-containing compound, or a combination thereof.

[0021] The samarium (Sm)-containing compound may be included in an amount of 0.01 to 1.2 mole parts with respect to 100 mole parts of the barium titanate-based main component powder.

[0022] The sub-component powder may further include a third sub-component compound including an aluminum (Al)-containing compound, a silicon (Si)-containing compound, a magnesium (Mg)-containing compound, a manganese (Mn)-containing compound, or a combination thereof.

[0023] The third sub-component-containing compound may be contained in an amount of 0.1 mole part to 2.5 mole parts with respect to 100 mole parts of the barium titanate-based main component powder.

[0024] The third sub-component-containing compound may contain the aluminum (Al)-containing compound and the silicon (Si)-containing compound.

Advantages of the Invention

[0025] The multilayer ceramic capacitor according to one embodiment can improve DC-bias characteristics and reliability.

Brief Description of the Drawings

[0026]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Modes for Carrying Out the Invention

[0027] 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, in the attached drawings, some components are exaggerated, omitted, or illustrated schematically, and the sizes of the components do not fully reflect the actual sizes.

[0028] The attached drawings are only for facilitating the understanding of the embodiments disclosed in this specification, and the technical ideas disclosed in this specification are not limited by the attached drawings. It should be understood that all modifications, equivalents, and alternatives included in the spirit and technical scope of the present invention are included.

[0029] 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 only used for the purpose of distinguishing one component from another.

[0030] Also, when a part such as a layer, film, region, plate, etc. is "on" or "above" another part, this includes not only the case where it is "directly above" the other part, but also the case where there are other parts in between. Conversely, when a part is "directly above" another part, it means that there are no other parts in between. Also, being "on" or "above" a reference part means being located above or below the reference part, and it does not necessarily mean being located "on" or "above" in the direction opposite to gravity.

[0031] Throughout the specification, terms such as "comprising" or "having" are intended to specify the presence of the features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, and should not be construed as precluding the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof. Therefore, when a part "comprises" a certain component, this means that it can further comprise other components rather than excluding other components unless there is a contrary description.

[0032] Also, throughout the specification, when it is said "on a plane", this means when looking at the target part from above, and when it is said "in a cross-section", this means when looking at the cross-section obtained by vertically cutting the target part from the side.

[0033] Also, throughout the specification, when it is said "connected", this does not only mean that two or more components are directly connected, but also means that two or more components are indirectly connected through other components, physically connected, not only physically connected but also electrically connected, or can be meant to be integrated although named differently depending on position or function.

[0034] Hereinafter, a multilayer ceramic capacitor according to an embodiment will be described with reference to FIGS. 1 to 3.

[0035] FIG. 1 is a perspective view showing a multilayer ceramic capacitor according to an embodiment, FIG. 2 is a cross-sectional view of the multilayer ceramic capacitor cut along the line I-I' in FIG. 1, and FIG. 3 is a cross-sectional view of the multilayer ceramic capacitor cut along the line II-II' in FIG. 1.

[0036] The L-axis, W-axis, and T-axis shown in FIGS. 1 to 3 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 wide surface (main surface) of the sheet-shaped component, and as an example, it can be used as the same concept as the stacking direction in which the dielectric layer 111 is stacked. The length direction (L-axis direction) may be a direction that extends parallel to the wide surface (main surface) of the sheet-shaped component and is substantially perpendicular to the thickness direction (T-axis direction), and as an example, it may be a 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 that extends parallel to the wide surface (main surface) of the sheet-shaped component and is 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 ceramic capacitor 100 according to the present embodiment includes a capacitor body 110 and external electrodes 131 and 132 disposed outside the capacitor body 110. The external electrodes 131 and 132 can include 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, a substantially hexahedral shape.

[0039] For the convenience of explanation of an embodiment, 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 one embodiment is not limited to this. For example, the first to sixth surfaces may be curved surfaces with a convex 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 this embodiment.

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

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

[0044] The capacitor body 110 can have an active region. The active region is a region where the dielectric layer 111 and the internal electrode layers 121, 122 are alternately arranged with each other, and is a part that contributes to the capacitance formation of the multilayer ceramic capacitor 100. Specifically, the active region may be a region where the first internal electrode 121 or the second internal electrode 122 stacked along the thickness direction (T-axis direction) overlaps.

[0045] Also, the capacitor body 110 can further include a cover portion and a side margin portion.

[0046] The cover part is a thickness-direction margin part and can be arranged on the first surface and the second surface sides of the active region in the thickness direction (T-axis direction), respectively. Such a cover part may be a single dielectric layer 111 or two or more dielectric layers 111 laminated on the upper surface and the lower surface of the active region, respectively.

[0047] The side margin part can be regarded as a side cover part and can be arranged on both side ends of the active region facing each other in the width direction (W-axis direction), that is, on the fifth surface and the sixth surface sides, respectively. When applying the conductive paste layer for the internal electrode layer on the surface of the dielectric green sheet, the conductive paste layer is applied only to a partial region of the surface of the dielectric green sheet, and dielectric green sheets without the conductive paste layer applied to both side surfaces of the surface of the dielectric green sheet are laminated and then fired, but the formation is not limited to such a formation method.

[0048] The cover part and the side margin part play a role in preventing damage to the first internal electrode 121 and the second internal electrode 122 due to physical or chemical stress.

[0049] The dielectric layer 111 contains at least one dielectric crystal grain (grain).

[0050] The dielectric crystal grain contains a barium titanate-based main component containing barium (Ba) and titanium (Ti), and a sub-component.

[0051] The barium titanate-based main component is a dielectric base material, has a high dielectric constant, and contributes to the formation of the dielectric constant of the multilayer ceramic capacitor 100.

[0052] The barium titanate-based main component can include, for example, BaTiO3, Ba(Ti,Zr)O3, Ba(Ti,Sn)O3, (Ba,Ca)TiO3, (Ba,Ca)(Ti,Ca)O3, (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.

[0053] The sub-components include a first sub-component and a second sub-component. The first sub-component is samarium (Sm), and the second sub-component may be a lanthanum-based element excluding samarium (Sm). That is, the second sub-component can include lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), or a combination thereof.

[0054] Sm 3+ has a larger ionic radius than, for example, Dy 3+ and a higher substitution efficiency as an A-site donor, so the free electron emission effect is increased and the control effect of the defect concentration is excellent. Also, sufficient grain growth can occur in the case of barium titanate doped with Sm compared to barium titanate doped with Dy, and high capacitance can be achieved. Therefore, according to one embodiment, by including samarium (Sm) as the first sub-component in the dielectric crystal grains, a multilayer ceramic capacitor with improved DC-bias characteristics and reliability can be ensured. Here, the improvement of the DC-bias characteristics means that the DC effective capacitance is improved, and the degree of capacitance reduction when a DC voltage is applied is reduced.

[0055] Also, according to one embodiment, by including another lanthanum-based element as a second sub-component together with samarium (Sm) as a first sub-component in the dielectric crystal grains, the DC-bias characteristics and reliability of the multilayer ceramic capacitor can be further improved.

[0056] Samarium (Sm) may be contained in the dielectric crystal grains in an amount of 0.01 atomic % to 1.2 atomic % with respect to 100 atomic % of titanium (Ti), for example, 0.05 atomic % to 1.1 atomic %, or 0.1 atomic % to 1.0 atomic %. When samarium (Sm) is contained within the dielectric crystal grains within the above content range, a multilayer ceramic capacitor excellent in DC-bias characteristics and reliability can be ensured.

[0057] The dielectric crystal grains can have a core-shell structure including a core and a shell surrounding at least a part of the core. Samarium (Sm) may be contained in both the core and the shell, and the atomic % of samarium (Sm) contained in the shell may be higher than the atomic % of samarium (Sm) contained in the core. Specifically, the atomic ratio of samarium (Sm) contained in the shell to samarium (Sm) contained in the core may be 1.2 to 2.5, for example, 1.3 to 2.2, or 1.5 to 2.0. When the atomic % of samarium (Sm) in the shell is higher than the atomic % of samarium (Sm) in the core, specifically, when having the atomic ratio within the above range, the DC-bias characteristics and reliability of the multilayer ceramic capacitor can be improved.

[0058] The second sub-component can include, as an example, terbium (Tb), dysprosium (Dy), or a combination thereof among the aforementioned lanthanum-based elements.

[0059] The second sub-component may be contained in the dielectric crystal grains in an amount of 1.2 atomic % to 2.0 atomic % with respect to 100 atomic % of titanium (Ti), for example, 1.3 atomic % to 1.9 atomic %, or 1.4 atomic % to 1.8 atomic %. When the second sub-component contains two or more elements, the content of the second sub-component means the sum of the contents of the respective elements.

[0060] When the second sub-component is contained within the above content range in the dielectric crystal grains, a multilayer ceramic capacitor excellent in DC-bias characteristics and reliability can be ensured.

[0061] The second sub-component may also be entirely contained in the core and the shell, and the atomic percentage of the second sub-component contained in the shell may be even higher than the atomic percentage of the second sub-component contained in the core. Specifically, the atomic ratio of the second sub-component contained in the shell to the second sub-component contained in the core may be 2 to 8, for example, 3 to 7, or 4 to 6. When the atomic percentage of the second sub-component in the shell is higher than the atomic percentage of the second sub-component in the core, specifically when having the atomic ratio within the above range, the DC-bias characteristics and reliability of the multilayer ceramic capacitor can be improved.

[0062] The sub-component can further contain a third sub-component. The third sub-component can contain aluminum (Al), silicon (Si), magnesium (Mg), manganese (Mn), or a combination thereof. When the third sub-component is contained in the dielectric crystal grains together with samarium (Sm) as the first sub-component and other lanthanum-based elements as the second sub-component, the DC-bias characteristics and reliability of the multilayer ceramic capacitor can be further improved.

[0063] The third sub-component may be contained within the range of 0.1 atomic % to 2.5 atomic % with respect to 100 atomic % of titanium (Ti) in the dielectric crystal grains, for example, 1.0 atomic % to 2.5 atomic %, or 1.4 atomic % to 2.5 atomic %. When the third sub-component is contained within the above content range in the dielectric crystal grains, a multilayer ceramic capacitor excellent in DC-bias characteristics and reliability can be ensured.

[0064] The third sub-component can include aluminum (Al) and silicon (Si) as an example. In this case, the atomic ratio of samarium (Sm) to the total of aluminum (Al) and silicon (Si) may be 0.01 to 0.7, for example, 0.05 to 0.7, or 0.1 to 0.7. When having the atomic ratio within the above range, the DC-bias characteristics and reliability of the multilayer ceramic capacitor can be improved.

[0065] The confirmation and respective contents of samarium (Sm) as the first sub-component, other lanthanum-based elements as the second sub-component, and optionally the third sub-component contained in the dielectric crystallites can be obtained by TEM-EDS (transmission electron microscope - energy dispersive spectroscopy) analysis.

[0066] Specifically, after the multilayer ceramic capacitor 100 is placed in an epoxy mixture and cured, the W-axis and T-axis direction surfaces (WT surfaces) of the capacitor body 110 are polished to a depth of 1 / 2 in the L-axis direction, and after fixation, it is maintained in a vacuum atmosphere chamber to obtain a cross-sectional sample so that the active region where the dielectric layer 111 and the internal electrode layers 121 and 122 intersect can be observed. Next, it can be measured with a transmission electron microscope (TEM) for the active region of the cross-sectional sample. For example, TEM can be measured under the condition of an acceleration voltage of 200 kV using Xe-FIB (focused ion beam) in a region of about 400 nm × 400 nm where at least one layer of the dielectric layer 111 can be seen in the active region. Then, in the TEM image of the measured cross-sectional sample, for each point in at least one dielectric crystallite within one dielectric layer, for example, each point in 1 to 10, or 2 to 5 dielectric crystallites, EDS analysis is performed to obtain the arithmetic mean value of the element contents. Specifically, for each point in each core and shell of at least one dielectric crystallite having a core-shell structure, for example, each point in 1 to 10, or 2 to 5 dielectric crystallites having a core-shell structure, EDS analysis is performed to obtain the arithmetic mean value of the element contents in each of the core and shell.

[0067] The diameter of the dielectric crystal grains may be 100 nm to 500 nm based on the maximum major axis, and may be, for example, 200 nm to 400 nm. When the diameter of the dielectric crystal grains is within the above range, excellent insulation resistance (IR) can be maintained while achieving high capacitance, thereby ensuring a laminated ceramic capacitor with excellent reliability.

[0068] The average thickness (average length in the T-axis direction) of the dielectric layer 111 may be 0.1 μm to 8.0 μm, and may be, for example, 0.1 μm to 4.0 μm. When the average thickness of the dielectric layer 111 is within the above range, the laminated ceramic capacitor has excellent reliability.

[0069] The average thickness of the dielectric layer 111 can be measured by scanning electron microscope (SEM) analysis after putting the laminated ceramic capacitor 100 into an epoxy mixture, curing it, polishing it, and then ion milling. The scanning electron microscope may use, for example, the Verios G4 product of thermofisher scientific, the measurement conditions are 10 kV and 0.2 nA, and the analysis magnification may be 100 times. It can be measured so that at least one layer or more, three layers or more, five layers or more, or ten layers or more of the dielectric layer 111 appear. In the scanning electron microscope (SEM) image, it may be the arithmetic mean value of the thickness of the dielectric layer 111 at 10 points separated by a predetermined interval from the reference point based on the central point in the length direction (L-axis direction) or width direction (W-axis direction) of the dielectric layer 111. 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 to 100 μm, 1 μm to 50 μm, or 1 μm to 10 μm. At this time, all 10 points must be located within the dielectric layer 111. When 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.

[0070] The first internal electrode 121 and the second internal electrode 122 are electrodes having different polarities from each other, and are alternately arranged so as to face each other along the T-axis direction with the dielectric layer 111 interposed therebetween, and one end of each is exposed through the third surface and the fourth surface of the capacitor body 110, respectively.

[0071] The first internal electrode 121 and the second internal electrode 122 are electrically insulated from each other by the dielectric layer 111 disposed therebetween.

[0072] The ends of the first internal electrode 121 and the second internal electrode 122 that are alternately exposed through the third surface and the fourth surface of the capacitor body 110 are respectively connected to the first external electrode 131 and the second external electrode 132 and electrically connected.

[0073] The first internal electrode 121 and the second internal electrode 122 may contain a conductive metal, for example, a metal such as Ni, Cu, Ag, Pd, Au, or an alloy thereof, for example, an Ag-Pd alloy.

[0074] Further, the first internal electrode 121 and the second internal electrode 122 may contain dielectric particles of the same composition system as the ceramic material contained in the dielectric layer 111.

[0075] 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.

[0076] The average thickness of the first internal electrode 121 and the second internal electrode 122 may be 0.1 μm to 2 μm. The average thickness of the first internal electrode 121 and the second internal electrode 122 can be measured by scanning electron microscope (SEM) analysis. Here, since the scanning electron microscope (SEM) analysis is the same as the method at the time of measuring the average thickness of the dielectric layer 111 described above, the description thereof is omitted.

[0077] The capacitor body 110 can be formed by firing a laminate in which a plurality of dielectric layers 111 and internal electrode layers 121 and 122 are laminated.

[0078] The first external electrode 131 and the second external electrode 132 are provided with voltages of different polarities, and are respectively connected to and electrically connected to the exposed portions of the first internal electrode 121 and the second internal electrode 122.

[0079] With the above-described 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 facing each other. At this time, the capacitance of the multilayer ceramic 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.

[0080] 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 the corners where the third surface and the fourth surface are in contact with the first surface and the second surface or the fifth surface and the sixth surface.

[0081] 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 play a role in improving the fixing strength of the first external electrode 131 and the second external electrode 132.

[0082] 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 so as to cover the sintered metal layer, and a plating layer disposed so as to cover the conductive resin layer.

[0083] The sintered metal layer can include a conductive metal and glass.

[0084] The conductive metal 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. For example, copper (Cu) can include copper (Cu) alloys. When the conductive metal contains copper, the metal other than copper may be contained in an amount of 5 mol parts or less with respect to 100 mol parts of copper.

[0085] The glass can include a composition in which oxides are mixed, and for example, 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), and the alkaline earth metal may be one or more selected from the group consisting of magnesium (Mg), calcium (Ca), strontium (Sr), and barium (Ba).

[0086] 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.

[0087] The conductive resin layer extends to the first and second surfaces or the fifth and sixth surfaces of the capacitor body 110, and 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.

[0088] The conductive resin layer contains a resin and a conductive metal.

[0089] 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 contain a phenol resin, an acrylic resin, a silicon resin, an epoxy resin, or a polyimide resin.

[0090] 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.

[0091] The conductive metal contained in the conductive resin layer can have a spherical, flake-shaped, or a combination of these forms. That is, the conductive metal may consist only of flake-shaped or only of spherical, or may be a form in which flakes and spheres are mixed.

[0092] 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.

[0093] The first external electrode 131 and the second external electrode 132 can further include a plating layer disposed outside the conductive resin layer.

[0094] The plating layer can include nickel (Ni), copper (Cu), tin (Sn), palladium (Pd), platinum (Pt), gold (Au), silver (Ag), tungsten (W), titanium (Ti), or lead (Pb) alone or an alloy thereof. For example, the plating layer may be a nickel (Ni) plating layer or a tin (Sn) plating layer, or may be in a form in which a nickel (Ni) plating layer and a tin (Sn) plating layer are sequentially laminated, or may be in a form in which a tin (Sn) plating layer, a nickel (Ni) plating layer, and a tin (Sn) plating layer are sequentially laminated. Also, the plating layer can include a plurality of nickel (Ni) plating layers and / or a plurality of tin (Sn) plating layers.

[0095] 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).

[0096] Hereinafter, a method for manufacturing the multilayer ceramic capacitor 100 according to an embodiment will be described.

[0097] The multilayer ceramic capacitor 100 according to an embodiment can be manufactured through the steps of: manufacturing a dielectric slurry by mixing a barium titanate-based main component powder and a sub-component powder including a samarium (Sm) containing compound and a second sub-component containing compound; manufacturing a dielectric green sheet using the dielectric slurry and forming a conductive paste layer on the surface of the dielectric green sheet; laminating the dielectric green sheets with the conductive paste layer formed thereon to manufacture a dielectric green sheet laminate; firing the dielectric green sheet laminate to manufacture a capacitor body including a dielectric layer and an internal electrode layer; and forming an external electrode on one surface of the capacitor body.

[0098] First, a dielectric slurry is manufactured by mixing a barium titanate-based main component powder and a sub-component powder.

[0099] The barium titanate-based main component powder can be produced by mixing a titanium (Ti) precursor and a barium (Ba) precursor.

[0100] The titanium (Ti) precursor may be an oxide, salt, alkoxide, etc. of titanium, and can include, for example, titanium dioxide, titanium diisopropoxide diacetylacetonate (TPA), titanium alkoxide, or a combination thereof. The barium (Ba) precursor can include BaO2, BaTiO3, BaCO3, BaO, or a combination thereof.

[0101] The barium (Ba) precursor may be included in an amount of 0.9 mol to 1.1 mol per 1 mol of the titanium (Ti) precursor.

[0102] The sub-component powder includes a samarium (Sm) - containing compound and a second sub-component - containing compound.

[0103] The samarium (Sm) - containing compound may be an oxide, nitride, or salt compound, or may be used in the form of a sol dispersed in an organic solvent.

[0104] The samarium (Sm) - containing compound may be mixed in an amount of 0.01 part by mole to 1.2 parts by mole per 100 parts by mole of the barium titanate-based main component powder, and may be mixed, for example, in an amount of 0.1 part by mole to 1.0 part by mole. When the samarium (Sm) - containing compound is mixed within the above content range, the DC - bias characteristics and reliability of the multilayer ceramic capacitor can be improved.

[0105] The second sub-component containing compound can include a lanthanum (La) containing compound, a cerium (Ce) containing compound, a praseodymium (Pr) containing compound, a neodymium (Nd) containing compound, a promethium (Pm) containing compound, a europium (Eu) containing compound, a gadolinium (Gd) containing compound, a terbium (Tb) containing compound, a dysprosium (Dy) containing compound, a holmium (Ho) containing compound, an erbium (Er) containing compound, a thulium (Tm) containing compound, a ytterbium (Yb) containing compound, a lutetium (Lu) containing compound, or a combination thereof. As an example, the second sub-component containing compound can include a terbium (Tb) containing compound, a dysprosium (Dy) containing compound, or a combination thereof.

[0106] The second sub-component containing compound may be an oxide, a nitride, or a salt compound, or may be used in the form of a sol dispersed in an organic solvent.

[0107] The second sub-component containing compound may be mixed in an amount of 1.2 to 2.0 mole parts, for example 1.4 to 1.8 mole parts, per 100 mole parts of the barium titanate-based main component powder. When the second sub-component containing compound is mixed within the above content range, the DC-bias characteristics and reliability of the multilayer ceramic capacitor can be improved.

[0108] The sub-component powder can further include a third sub-component containing compound.

[0109] The third sub-component containing compound can include an aluminum (Al) containing compound, a silicon (Si) containing compound, a magnesium (Mg) containing compound, a manganese (Mn) containing compound, or a combination thereof. As an example, the third sub-component containing compound can include an aluminum (Al) containing compound and a silicon (Si) containing compound.

[0110] The third sub-component containing compound may be an oxide, a nitride, or a salt compound, or may be used in the form of a sol dispersed in an organic solvent.

[0111] The third sub-component containing compound may be mixed in an amount of 0.1 mole part to 2.5 mole parts, for example, 1.4 mole parts to 2.5 mole parts, based on 100 mole parts of the barium titanate-based main component powder. When the third sub-component containing compound is mixed within the above content range, the DC-bias characteristics and reliability of the multilayer ceramic capacitor can be improved.

[0112] The dielectric slurry can be produced by additionally mixing additives such as a dispersant, a binder, a plasticizer, a lubricant, an antistatic agent, etc. and a solvent, in addition to the obtained dielectric powder.

[0113] The dispersant can include, for example, a phosphate ester-based dispersant, a polycarboxylic acid-based dispersant, or a combination thereof. The dispersant may be mixed in an amount of 0.1 part by weight to 5 parts by weight, for example, 0.3 part by weight to 3 parts by weight, based on 100 parts by weight of the barium titanate-based main component powder. When the dispersant is mixed within the above content range, the dispersibility of the dielectric slurry is excellent, and the amount of impurities contained in the produced dielectric layer can be reduced.

[0114] The binder may be, for example, an acrylic resin, a polyvinyl butyral resin, a polyvinyl acetal resin, an ethyl cellulose resin, etc. The binder may be added in an amount of 0.1 part by weight to 50 parts by weight, for example, 3 parts by weight to 30 parts by weight, based on 100 parts by weight of the barium titanate-based main component powder. When the binder is mixed within the above content range, the dispersibility of the dielectric slurry is excellent, and the amount of impurities contained in the produced dielectric layer can be reduced.

[0115] Plasticizers may be, for example, phthalic acid-based compounds such as dioctyl phthalate, benzyl butyl phthalate, dibutyl phthalate, dihexyl phthalate, di(2-ethylhexyl) phthalate, di(2-ethylbutyl) phthalate; adipic acid-based compounds such as dihexyl adipate, di(2-ethylhexyl) adipate; glycol-based compounds such as ethylene glycol, diethylene glycol, triethylene glycol; glycol ester-based compounds such as triethylene glycol dibutyrate, triethylene glycol di(2-ethylbutyrate), triethylene glycol di(2-ethylhexanoate), etc. The plasticizer may be added in an amount of 0.1 to 20 parts by weight, for example, 1 to 10 parts by weight, based on 100 parts by weight of the barium titanate-based main component powder. When the plasticizer is mixed within the above content range, the dispersibility of the dielectric slurry is excellent, and the amount of impurities contained in the produced dielectric layer can be reduced.

[0116] Solvents may be aqueous solvents such as water; alcohol-based solvents such as ethanol, methanol, benzyl alcohol, methoxyethanol; glycol-based solvents such as ethylene glycol, diethylene glycol; ketone-based solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone; ester-based solvents such as butyl acetate, ethyl acetate, carbitol acetate, butyl carbitol acetate; ether-based solvents such as methyl cellosolve, ethyl cellosolve, butyl ether, tetrahydrofuran; aromatic solvents such as benzene, toluene, xylene, etc. For example, considering the solubility and dispersibility of various additives contained in the dielectric slurry, an alcohol-based solvent or an aromatic solvent can be used as the solvent. The solvent may be mixed in an amount of 50 to 1000 parts by weight, for example, 100 to 500 parts by weight, based on 100 parts by weight of the barium titanate-based main component powder. When the solvent is mixed within the above content range, the dielectric slurry components are sufficiently mixed, and then the removal of the solvent is also easy.

[0117] The mixing of the aforementioned dielectric slurry can be carried out using a wet ball mill or a stirring mill. When using zirconia balls in a wet ball mill, a large number of zirconia balls with a diameter of 0.1 mm to 10 mm can be used for wet mixing for 8 hours to 48 hours, or 10 hours to 24 hours.

[0118] The produced dielectric slurry is formed as a dielectric layer after firing.

[0119] As a method for forming the produced dielectric slurry into a sheet shape, tape forming methods such as the doctor blade method and the calendar roll method can be used. For example, an on-roll coater using a head discharge method can be used, and then a dielectric green sheet can be obtained by drying the formed body.

[0120] In order to form a conductive paste layer that becomes an internal electrode layer after firing, a conductive powder made of a conductive metal or its alloy, a binder, and a solvent can be mixed to produce a conductive paste. Also, barium titanate powder may be mixed together 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. A conductive paste is applied in a predetermined pattern on the surface of the dielectric green sheet by various printing methods such as screen printing or transfer methods to form a conductive paste layer.

[0121] The conductive powder can contain nickel (Ni) or a nickel (Ni) alloy.

[0122] Next, after laminating the dielectric green sheet with the internal electrode pattern over a plurality of layers, a dielectric green sheet laminate is manufactured by pressing in the lamination direction. At this time, the dielectric green sheet and the internal electrode pattern can be laminated so that the dielectric green sheet is located on the upper and lower surfaces in the lamination direction of the dielectric green sheet laminate.

[0123] The step of cutting the manufactured dielectric green sheet laminate into a predetermined size by dicing or the like can be selectively performed.

[0124] Further, the dielectric green sheet laminate can be solidified and dried to remove a plasticizer or the like if necessary, and can be barrel-polished using a horizontal centrifugal barrel polishing machine or the like after the solidification and drying. In barrel polishing, the dielectric green sheet laminate is put into a barrel container together with a medium and a polishing liquid, and unnecessary parts such as burrs generated during cutting can be polished by applying rotational motion, vibration, or the like to the barrel container. Further, after barrel polishing, the dielectric green sheet laminate can be washed with a cleaning liquid such as water and dried.

[0125] Next, a capacitor body can be manufactured by subjecting the dielectric green sheet laminate to a debinding treatment and firing.

[0126] The debinding treatment conditions can be appropriately adjusted according to the components of the dielectric layer and the internal electrode layer. For example, the heating rate during the debinding treatment may be 5°C / hour to 300°C / hour, the holding temperature may be 180°C to 400°C, and the temperature holding time may be 0.5 hour to 24 hours. During the debinding treatment, the atmosphere may be air or a reducing atmosphere.

[0127] The firing treatment conditions 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, firing can be performed at a temperature of 1100°C to 1400°C, for example, at a temperature of 1200°C to 1350°C. Further, firing can be performed for 0.5 hour to 8 hours, for example, 1 hour to 3 hours. Further, firing can be performed in a reducing atmosphere, for example, an atmosphere in which a mixed gas of nitrogen and hydrogen is humidified. When the internal electrode contains nickel (Ni) or a nickel (Ni) alloy, the oxygen partial pressure in the firing atmosphere may be 1.0×10 -14 MPa to 1.0×10 -10 MPa.

[0128] After the firing process, annealing can be performed if necessary. Annealing is a process for re-oxidizing the dielectric layer, and can be performed when firing is carried out in a reducing atmosphere. The conditions of the annealing process can also be appropriately adjusted according to the components of the dielectric layer. For example, the temperature during annealing may be 950°C to 1150°C, the time may be 0 hours to 20 hours, and the heating rate may be 50°C / hour to 500°C / hour. The annealing atmosphere may be a humidified nitrogen gas (N2) atmosphere, and the oxygen partial pressure may be 1.0×10 -9 MPa to 1.0×10 -5 MPa.

[0129] In the debinding process, firing process, or annealing process, in order to humidify nitrogen gas, mixed gas, etc., for example, a wetter can be used. In this case, the water temperature may be 5°C to 75°C. The debinding process, firing process, and annealing process can be carried out continuously or independently.

[0130] Optionally, surface treatments such as sandblasting, laser irradiation, and barrel polishing can be performed on the third and fourth surfaces of the manufactured capacitor body 110. By performing such surface treatments, 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 part.

[0131] Next, an external electrode is formed on one surface of the manufactured capacitor body 110.

[0132] As an example, after applying a paste for forming a sintered metal layer as an external electrode and sintering it, a sintered metal layer can be formed.

[0133] The paste for forming a sintered metal layer can contain a conductive metal and glass. Since the descriptions of the conductive metal and glass are the same as those described above, repetitive explanations are omitted. Further, the paste for forming a sintered metal layer can selectively contain a binder, a solvent, a dispersant, a plasticizer, an oxide powder, etc. As the binder, for example, ethyl cellulose, acrylic, butyral, etc. can be used, and as the solvent, organic solvents such as terpineol, butyl carbitol, alcohol, methyl ethyl ketone, acetone, toluene, etc. or an aqueous solvent can be used.

[0134] As a method of applying the paste for forming a sintered metal layer to the outer surface of the capacitor body 110, various printing methods such as dip method, screen printing, an application method using a dispenser, a spraying method using a spray, etc. can be used. The paste for forming a sintered metal layer is applied to at least the third and fourth surfaces of the capacitor body 110, and can also be applied selectively 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 formed.

[0135] Thereafter, the capacitor body 110 coated with the paste for forming a sintered metal layer is dried and sintered at a temperature of 700 °C to 1000 °C for 0.1 hour to 3 hours to form a sintered metal layer.

[0136] 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 110 and then curing it.

[0137] The paste for forming a conductive resin layer can contain a resin and, optionally, a conductive metal or a non-conductive filler. Since the descriptions of the conductive metal and the resin are the same as those described above, repetitive explanations are omitted. Further, the paste for forming a conductive resin layer can optionally contain a binder, a solvent, a dispersant, a plasticizer, an oxide powder, etc. As the binder, for example, ethyl cellulose, acrylic, butyral, etc. can be used, and as the solvent, organic solvents such as terpineol, butyl carbitol, alcohol, methyl ethyl ketone, acetone, toluene, etc. or an aqueous solvent can be used.

[0138] As an example, the method for forming a conductive resin layer can be to dip the capacitor body 110 into the paste for forming a conductive resin layer and then cure it, or to print the paste for forming a 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 a conductive resin layer on the surface of the capacitor body 110 and then cure it to form.

[0139] Next, a plating layer is formed outside the conductive resin layer.

[0140] As an example, the plating layer can be formed by a plating method, and can also be formed by sputtering or electric deposition.

[0141] Hereinafter, the above-described embodiments will be described in more detail through examples. However, the following examples are for illustrative purposes only and do not limit the scope of rights.

Examples

[0142] (Manufacturing of multilayer ceramic capacitors) Examples 1 to 8 and Comparative Examples 1 to 7 Powder mainly composed of barium titanate (BaTiO3), and as secondary component powders, samarium oxide (Sm2O3), dysprosium oxide (Dy2O3), terbium oxide (Tb4O7), aluminum oxide (Al2O3), and silicon dioxide (SiO2) were mixed according to the composition shown in Table 1 below to produce a dielectric slurry. The mixing was carried out by using zirconia balls (ZrO2 balls) as a dispersion medium, adding ethanol / toluene, a wetting dispersant, and polyvinyl butyral (PVB) resin as a binder together, and then mechanically milling them.

[0143] A dielectric green sheet was produced from the produced dielectric slurry using an on-roll coater of the head ejection method.

[0144] A conductive paste layer containing nickel (Ni) was printed on the surface of the dielectric green sheet, and the dielectric green sheets with the conductive paste layer formed were laminated and pressed to produce a dielectric green sheet laminate.

[0145] The dielectric green sheet laminate was subjected to a plasticizing process at 400 °C or lower in a nitrogen atmosphere, and then fired under the conditions of a firing temperature of 1300 °C or lower and a hydrogen concentration of 1.0% H2 or lower.

[0146] Next, a multilayer ceramic capacitor was produced through processes such as forming an external electrode and plating.

[0147]

Table 1

[0148] Evaluation 1: TEM-EDS analysis TEM-EDS (transmission electron microscope - energy dispersive spectroscopy) analysis was performed on the multilayer ceramic capacitors produced in Examples 1 to 8 and Comparative Examples 1 to 7, and the results are shown in Tables 2 and 3 and Figures 4 to 6 below.

[0149] The TEM-EDS analysis was measured by the following method. After the multilayer ceramic capacitors manufactured in Examples 1 to 8 and Comparative Examples 1 to 7 were put into an epoxy mixture and cured, the W-axis and T-axis direction surfaces (WT surfaces) of the capacitor body 110 were polished to a depth of 1 / 2 in the L-axis direction, and after fixing, it was maintained in a vacuum atmosphere chamber to obtain a cross-sectional sample so that the active region where the dielectric layer and the internal electrode layer intersect could be observed. The active region of the cross-sectional sample was measured by TEM. The TEM was measured under the condition of an acceleration voltage of 200 kV using Xe-FIB (focused ion beam) in a region of about 400 nm × 400 nm where at least one layer of the dielectric layer 111 could be seen in the active region.

[0150] In the transmission electron microscope (TEM) image of the measured cross-sectional sample, the contents of Sm, Dy, and Tb present in the dielectric grains were confirmed by EDS line analysis. Specifically, as shown in FIG. 4, the atomic percentages of each component were confirmed for the line section connected by a straight line from the starting point to the ending point of the dielectric grain.

[0151] FIG. 4 is a low-magnification TEM image of the dielectric layer according to Example 1, and FIG. 5 is an EDS line analysis diagram of the dielectric grains shown in FIG. 4.

[0152] Referring to FIG. 5, the relative atomic percentages of Sm, Dy, and Tb can be confirmed, and it can be confirmed that the concentration of samarium (Sm) tends to increase in the shell region compared to the core.

[0153] FIG. 6 is a high-magnification TEM image of the dielectric layer according to Example 1.

[0154] Also, in the transmission electron microscope (TEM) image of the cross-sectional sample measured for Example 1, for the three dielectric crystallites (grains) in one dielectric layer as shown in FIG. 6, EDS analysis was performed on the points in the core and shell of each dielectric crystallite. By EDS analysis, the arithmetic mean values of the atomic percentages of each O, Ti, Dy, and Sm component at the three core points and the arithmetic mean values of the atomic percentages of each O, Ti, Dy, and Sm component at the three shell points were obtained, and the results are shown in Table 2 below.

[0155]

Table 2

[0156] From Table 2 above, in the case of Example 1, it can be seen that samarium (Sm) and dysprosium (Dy) have a higher atomic percentage, that is, a higher concentration, in the shell region compared to the core.

[0157] Evaluation 2: Reliability For the multilayer ceramic capacitors manufactured in Examples 1 to 8 and Comparative Examples 1 to 7, the dielectric constant, MTTF, and insulation resistance (IR) levels were measured, and the results are shown in Table 3 below.

[0158] The dielectric constant was measured under the conditions of 1 kHz and 0.5 V.

[0159] MTTF (mean time to failure) was measured by determining the average failure time (hr) at which a failure occurs under the conditions of a temperature of 125°C and a voltage of 9.45 V. In Table 3 below, ○ indicates that the average failure time is 11 hours or more, and X indicates that the average failure time is less than 11 hours.

[0160] The insulation resistance (IR) level can be obtained during high-temperature accelerated life test (HALT) measurement under the conditions of 125°C, 9.45 V, and 0 hours using an ESPEC (PV-222, HALT) facility.

[0161]

Table 3

[0162] Through Table 3 above, in Examples 1 to 8 in which a dielectric crystal grain contains samarium (Sm) and a second sub-component such as dysprosium (Dy) and terbium (Tb) and the entire second sub-component has an atomic percentage within a predetermined range, it can be seen that the dielectric constant, MTTF, and insulation resistance (IR) levels are all superior compared to Comparative Examples 1 to 7.

[0163] Also, 40 each of the multilayer ceramic capacitors manufactured in Example 3 and 5 and Comparative Example 1 were prepared and mounted on a measurement substrate, and the high-temperature harsh reliability (HALT) was measured under the conditions of 125 ° C., 9.45 V, and 48 hours using an ESPEC (PV-222, HALT) facility, and the results are shown in FIGS. 7 to 9.

[0164] FIG. 7 is a graph showing the high-temperature harsh reliability of the multilayer ceramic capacitor according to Comparative Example 1, FIG. 8 is a graph showing the high-temperature harsh reliability of the multilayer ceramic capacitor according to Example 3, and FIG. 9 is a graph showing the high-temperature harsh reliability of the multilayer ceramic capacitor according to Example 5.

[0165] Referring to FIGS. 7 to 9, in Examples 3 and 5 in which a dielectric crystal grain contains samarium (Sm) and a second sub-component such as dysprosium (Dy) and terbium (Tb) and the entire second sub-component has an atomic percentage within a predetermined range, it can be seen that the high-temperature harsh reliability is superior compared to Comparative Example 1.

[0166] 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 description of the invention, and the accompanying drawings, and it is natural that this also belongs to the scope of the present invention.

Description of Reference Numerals

[0167] 100: Multilayer ceramic capacitor 110: Capacitor body 111: Dielectric layer 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 an internal electrode layer, and including an external electrode disposed outside the capacitor body, wherein the dielectric layer includes at least one dielectric grain, the dielectric grain includes a barium titanate-based main component containing barium (Ba) and titanium (Ti), and a sub-component, the sub-component includes samarium (Sm) as a first sub-component and a second sub-component, the second sub-component includes lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), or a combination thereof, the second sub-component is contained in an amount of 1.2 atomic % to 2.0 atomic % with respect to 100 atomic % of the titanium (Ti), a multilayer ceramic capacitor.

2. The multilayer ceramic capacitor according to claim 1, wherein the second sub-component includes the terbium (Tb), the dysprosium (Dy), or a combination thereof.

3. The dielectric grain includes a core and a shell surrounding at least a part of the core, the second sub-component is contained in the core and the shell, the multilayer ceramic capacitor according to claim 1, wherein the atomic % of the second sub-component contained in the shell is higher than the atomic % of the second sub-component contained in the core.

4. The multilayer ceramic capacitor according to claim 3, wherein the atomic ratio of the second sub-component contained in the shell to the second sub-component contained in the core is 2 to 8.

5. The multilayer ceramic capacitor according to claim 1, wherein the samarium (Sm) is contained in an amount of 0.01 atomic % to 1.2 atomic % with respect to 100 atomic % of the titanium (Ti).

6. The dielectric grain includes a core and a shell surrounding at least a part of the core, the samarium (Sm) is contained in the core and the shell, the multilayer ceramic capacitor according to claim 1, wherein the atomic % of the samarium (Sm) contained in the shell is higher than the atomic % of the samarium (Sm) contained in the core.

7. The laminated ceramic capacitor according to claim 6, wherein an atomic ratio of samarium (Sm) contained in the shell to samarium (Sm) contained in the core is 1.2 to 2.

5.

8. The laminated ceramic capacitor according to claim 1, wherein the sub-component further includes a third sub-component containing aluminum (Al), silicon (Si), magnesium (Mg), manganese (Mn), or a combination thereof.

9. The laminated ceramic capacitor according to claim 8, wherein the third sub-component is contained in an amount of 0.1 atomic % to 2.5 atomic % with respect to 100 atomic % of titanium (Ti).

10. The laminated ceramic capacitor according to claim 8, wherein the third sub-component contains the aluminum (Al) and the silicon (Si).

11. The laminated ceramic capacitor according to claim 10, wherein an atomic ratio of samarium (Sm) to a total of the aluminum (Al) and the silicon (Si) is 0.01 to 0.

7.

12. The laminated ceramic capacitor according to claim 8, wherein a diameter of the dielectric crystal grains is 100 nm to 500 nm.

13. A step of producing a dielectric slurry by mixing a barium titanate-based main component powder and a sub-component powder containing a samarium (Sm) - containing compound and a second sub-component - containing compound; A step of producing a dielectric green sheet using the dielectric slurry and forming a conductive paste layer on a surface of the dielectric green sheet; A step of laminating the dielectric green sheet on which the conductive paste layer is formed to produce a dielectric green sheet laminate; A step of firing the dielectric green sheet laminate to produce a capacitor body including a dielectric layer and an internal electrode layer; and A step of forming an external electrode on one surface of the capacitor body, The second sub-component - containing compound includes a lanthanum (La) - containing compound, a cerium (Ce) - containing compound, a praseodymium (Pr) - containing compound, a neodymium (Nd) - containing compound, a promethium (Pm) - containing compound, a europium (Eu) - containing compound, a gadolinium (Gd) - containing compound, a terbium (Tb) - containing compound, a dysprosium (Dy) - containing compound, a holmium (Ho) - containing compound, an erbium (Er) - containing compound, a thulium (Tm) - containing compound, a ytterbium (Yb) - containing compound, a lutetium (Lu) - containing compound, or a combination thereof. A method for manufacturing a multilayer ceramic capacitor, wherein the compound containing the second sub-component is contained in an amount of 1.2 to 2.0 mole parts with respect to 100 mole parts of the barium titanate-based main component powder.

14. The method for manufacturing a multilayer ceramic capacitor according to claim 13, wherein the compound containing the second sub-component contains the terbium (Tb) -containing compound, the dysprosium (Dy) -containing compound, or a combination thereof.

15. The method for manufacturing a multilayer ceramic capacitor according to claim 13, wherein the samarium (Sm) -containing compound is contained in an amount of 0.01 to 1.2 mole parts with respect to 100 mole parts of the barium titanate-based main component powder.

16. The method for manufacturing a multilayer ceramic capacitor according to claim 13, wherein the sub-component powder further contains a compound containing a third sub-component, which contains an aluminum (Al) -containing compound, a silicon (Si) -containing compound, a magnesium (Mg) -containing compound, a manganese (Mn) -containing compound, or a combination thereof.

17. The method for manufacturing a multilayer ceramic capacitor according to claim 16, wherein the compound containing the third sub-component is contained in an amount of 0.1 to 2.5 mole parts with respect to 100 mole parts of the barium titanate-based main component powder.

18. The method for manufacturing a multilayer ceramic capacitor according to claim 16, wherein the compound containing the third sub-component contains the aluminum (Al) -containing compound and the silicon (Si) -containing compound.

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