Multilayered capacitor

Abstract

To provide a multilayered capacitor with improved reliability and high capacity by improving the smoothness and connectivity of internal electrodes.SOLUTION: A multilayered capacitor according to the present disclosure, includes: a capacitor body that includes a dielectric layer and an internal electrode; and an external electrode that is arranged on an outside of the capacitor body. When the internal electrode includes a Ni-Ge alloy, an average content (wt%) of Ge relative to Ni at a center part of the internal electrode is denoted by X, and an average content (wt%) of Ge relative to Ni at points spaced 20 nm apart from an interface arranged between the internal electrode and the dielectric layer toward the center portion of the internal electrode is denoted by Y, a relationship between X and Y satisfies a formula 1. The formula 1 is similar to one described in the specifications.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a stacked capacitor. [Background technology]

[0002] In recent years, as electronic devices have rapidly become more multifunctional and smaller, electronic components have also become smaller and their performance has improved at a rapid pace. In addition, there has been a great increase in the demand for high reliability in electrical devices used in automobiles or network equipment, and in electronic components used in industry.

[0003] To meet these market demands, the race to develop technology for passive components such as inductors, capacitors, and resistors is accelerating. In particular, the use and volume of multilayer ceramic capacitors (MLCCs) as passive components continues to grow, and many efforts are being made to stay ahead of the market in the development of various products.

[0004] Furthermore, multilayer capacitors are capacitors manufactured by stacking dielectric layers and internal electrodes, and are used in a variety of electronic devices such as mobile phones, notebook computers, and LCD TVs.

[0005] In recent years, with the development of technology, there is a demand for miniaturization and high capacitance of multilayer capacitors, which requires a reduction in the thickness of the internal electrodes and dielectric layers. When the thickness of the dielectric layers is reduced, the electric field strength applied to each layer becomes relatively stronger, which leads to a decrease in the reliability of the capacitor, and the capacitance also decreases due to the deterioration of electrode connectivity. Summary of the Invention [Problem to be solved by the invention]

[0006] According to one aspect of the embodiment, there is provided a multilayer capacitor having improved smoothness and connectivity of internal electrodes, thereby improving reliability and realizing high capacitance.

[0007] However, the problems to be solved by the embodiments are not limited to the problems described above, and can be expanded in various ways within the scope of the technical ideas included in the embodiments. [Means for solving the problem]

[0008] According to an embodiment, a multilayer capacitor includes a capacitor body including a dielectric layer and an internal electrode, and an external electrode disposed on an outer side of the capacitor body; the internal electrode includes a Ni-Ge alloy; When the average content (wt%) of Ge relative to Ni at the center of the internal electrode is X, and the average content (wt%) of Ge relative to Ni at a point 20 nm away from the interface between the internal electrode and the dielectric layer toward the center of the internal electrode is Y, the relationship between X and Y satisfies the following formula 1. [Formula 1]

number

[0009] The X value may be 0.90% by weight to 1.80% by weight.

[0010] The Y value may be 1.00% by weight to 1.50% by weight.

[0011] The internal electrodes may have an average thickness of 0.05 μm to 1 μm.

[0012] The dielectric layer may have an average thickness of 0.05 μm to 2.5 μm.

[0013] The dielectric layer may include a dielectric material including a major component and a minor component.

[0014] The main component is Ba. mTiO3 (0.995 ≤ m ≤ 1.010), (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), (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 combinations thereof.

[0015] The sub-components may include dysprosium (Dy), vanadium (V), manganese (Mn), chromium (Cr), silicon (Si), aluminum (Al), magnesium (Mg), tin (Sn), antimony (Sb), germanium (Ge), gallium (Ga), indium (In), barium (Ba), lanthanum (La), yttrium (Y), actinium (Ac), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), hafnium (Hf), or combinations thereof.

[0016] 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 Ni-Ge alloy. The average content (by weight %) of Ni relative to Ge in the entire internal electrode is 0.1 wt% to 10 wt%. Let the average content (by weight %) of Ni relative to Ge at the center of the internal electrode be X, and let the average content (by weight %) of Ni relative to Ge at a point 20 nm away from the interface disposed between the internal electrode and the dielectric layer toward the center of the internal electrode be Y. When this is the case, the relationship between X and Y satisfies the following formula 1. [Formula 1] [Number] The X value can be 0.90 wt% to 1.80 wt%.

[0017] The Y value can be 1.00 wt% to 1.50 wt%.

[0018] The average thickness of the internal electrode can be 0.05 μm to 1 μm.

[0019] The average thickness of the dielectric layer can be 0.05 μm to 2.5 μm.

[0020] The dielectric layer can contain a dielectric including a main component and a sub-component.

[0021] The main component is Ba m TiO3 (0.995 ≤ m ≤ 1.010), (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), (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 a combination thereof.

[0022] The minor component may include dysprosium (Dy), vanadium (V), manganese (Mn), chromium (Cr), silicon (Si), aluminum (Al), magnesium (Mg), tin (Sn), antimony (Sb), germanium (Ge), gallium (Ga), indium (In), barium (Ba), lanthanum (La), yttrium (Y), actinium (Ac), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), hafnium (Hf), or a combination thereof. Effect of the Invention

[0023] According to an embodiment of the multilayer capacitor, the smoothness and connectivity of the internal electrodes are improved, thereby improving reliability and providing a high capacitance.

[0024] However, the various and beneficial advantages and effects of the present invention are not limited to the above, and will be more easily understood in the course of describing specific implementation examples of the present invention. [Brief description of the drawings]

[0025] [Figure 1] FIG. 1 is a perspective view showing a stacked capacitor according to an embodiment; [Diagram 2] 2 is a cross-sectional view of the multilayer capacitor taken along line II' in FIG. [Diagram 3] 2 is an exploded perspective view showing a laminated structure of an internal electrode layer from the capacitor body in FIG. 1. [Figure 4] 4 is a TEM image showing a component analysis result of an internal electrode included in a multilayer capacitor according to an embodiment. [Diagram 5] This is EDS mapping of Ni. [Figure 6] This is EDS mapping of Ge. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] Hereinafter, the embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art to which the present invention pertains can easily carry out the present invention. In the drawings, parts unnecessary for the explanation are omitted in order to clearly explain the present invention, and the same or similar components are given the same reference numerals throughout the specification. In addition, the accompanying drawings are intended to facilitate understanding of the embodiments disclosed in the present specification, and the technical ideas disclosed in the present specification are not limited by the accompanying drawings, and it should be understood that the accompanying drawings include all modifications, equivalents, and alternatives included in the ideas and technical scope of the present invention.

[0027] Terms including ordinal numbers such as first, second, etc. may be used to describe various components, but the components are not limited by the terms. The terms are used only to distinguish one component from another.

[0028] When a component is described as "connected" or "connected" to another component, it should be understood that it may be directly connected, connected, or facing the other component, but there may also be other components in between. On the other hand, when a component is described as "directly connected" or "directly connected" to another component, it should be understood that there are no other components in between.

[0029] Throughout the specification, terms such as "comprises" or "having" are to be understood as specifying the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, but without precluding the presence or additional possibility of one or more other features, numbers, steps, operations, components, parts, or combinations thereof. Thus, when a part is described as "comprising" other elements, this means that it can further include the other elements, but not excluding the other elements, unless specifically stated to the contrary.

[0030] FIG. 1 is a perspective view showing a multilayer capacitor 100 according to one embodiment, FIG. 2 is a cross-sectional view of the multilayer capacitor 100 cut along line II' in FIG. 1, and FIG. 3 is an exploded perspective view showing the stacked structure of internal electrodes in the capacitor body 110 in FIG. 1.

[0031] To clearly explain the present embodiment, the L axis, W axis, and T axis shown in the drawings respectively indicate the length direction, width direction, and thickness direction of the capacitor body 110. Here, the thickness direction (T axis direction) is a direction perpendicular to the wide surface (main surface) of the sheet-shaped component, and can be used in the same concept as the lamination direction in which the dielectric layers 111 are laminated, for example. The length direction (L axis direction) is a direction extending parallel to the wide surface (main surface) of the sheet-shaped component and can be a direction approximately perpendicular to the thickness direction (T axis direction), and can be a direction in which the first external electrode 131 and the second external electrode 132 are located on both sides, for example. The width direction (W axis direction) can be a direction extending parallel to the wide surface (main surface) of the sheet-shaped component and approximately perpendicular to the thickness direction (T axis direction) and the length direction (L axis direction), and the length of the length direction (L axis direction) of the sheet-shaped component can be longer than the length of the width direction (W axis direction).

[0032] 1 to 3, a multilayer capacitor 100 according to one embodiment may include a capacitor body 110, and a first external electrode 131 and a second external electrode 132 arranged at opposite ends of the capacitor body 110 in the longitudinal direction (L-axis direction).

[0033] The capacitor body 110 may have a generally hexahedral shape, for example.

[0034] In this embodiment, for ease of explanation, the two surfaces of capacitor body 110 that face each other in the thickness direction (T-axis direction) can be defined as the first surface and the second surface, the two surfaces connected to the first surface and the second surface and facing each other in the length direction (L-axis direction) can be defined as the third surface and the fourth surface, and the two surfaces connected to the first surface and the second surface, connected to the third surface and the fourth surface, and facing each other in the width direction (W-axis direction) can be defined as the fifth surface and the sixth surface.

[0035] As an example, the first surface of the lower surface can be the surface facing the mounting direction. Also, the first surface to the sixth surface can be flat, but this embodiment is not limited to this. For example, the first surface to the sixth surface can be a convex curved surface in the center, and the corners that are the boundaries between each surface can be rounded.

[0036] The shape and size of the capacitor body 110 and the number of laminated dielectric layers 111 are not limited to those shown in the drawings of this embodiment.

[0037] The capacitor body 110 is formed by stacking a plurality of dielectric layers 111 in the thickness direction (T-axis direction) and then firing the same, and includes first internal electrode layers 121 and second internal electrode layers 122 arranged alternately in the thickness direction (T-axis direction) between the plurality of dielectric layers 111.

[0038] At this time, the boundaries between the adjacent dielectric layers 111 of the capacitor body 110 may be integrated to such an extent that it is difficult to confirm the boundaries without using a scanning electron microscope (SEM).

[0039] The capacitor body 110 may also include an active area and a cover area 112 , 113 .

[0040] The active area is a portion that contributes to forming the capacitance of the multilayer capacitor 100. For example, the active area may be an overlapping area of ​​the first internal electrode layer 121 or the second internal electrode layer 122 stacked along the thickness direction (T-axis direction).

[0041] The cover regions 112 and 113 may be located on the first and second surfaces of the active region in the thickness direction (T-axis direction) as thickness direction margins. The cover regions 112 and 113 may be a single dielectric layer 111 or two or more dielectric layers 111 stacked on the upper and lower surfaces of the active region, respectively.

[0042] In addition, the capacitor body 110 may further include a side cover region. The side cover region may be located on the fifth and sixth sides of the active region in the width direction (W-axis direction) as a width direction margin part. Such a side cover region may be formed by applying a conductive paste layer for forming an internal electrode layer only to a part of the surface of the dielectric green sheet when applying a conductive paste layer for forming an internal electrode layer on the surface of the dielectric green sheet, laminating dielectric green sheets on both side surfaces of the surface of the dielectric green sheet without applying a conductive paste layer, and then firing the laminate.

[0043] The cover regions 112, 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.

[0044] The multilayer capacitor 100 according to one embodiment includes a capacitor body 110 including a dielectric layer 111 and internal electrodes 121, 122, and external electrodes 131, 132 disposed on the outside of the capacitor body 110, where the internal electrodes 121, 122 include a Ni-Ge alloy.

[0045] Ge (Germanium) is an element with a tendency to oxidize that is very similar to Sn (Tin). When Ge is added during the manufacture of the internal electrode and sintered together with Ni in a reducing atmosphere, a Ni-Ge alloy is formed uniformly throughout the internal electrode.

[0046] The Ni-Ge alloy can reduce the grain boundary energy and surface tension of Ni, improving the smoothness and connectivity of the internal electrodes. If the smoothness of the internal electrodes 121 and 122 is improved, the strength of the electric field applied per dielectric layer can be dispersed even if the thickness of the dielectric layer 111 is reduced.

[0047] Furthermore, alloying Ge, which is a semimetal, with Ni improves the insulation properties of the interface between the dielectric layer 111 and the internal electrodes 121, 122, thereby improving reliability. In addition, the sintering speed of Ni is slowed down during the alloying process with Ge, which further improves electrode connectivity and allows a capacitor with higher capacitance to be realized.

[0048] The internal electrodes 121 and 122 containing the Ni-Ge alloy are formed by adding Ge or GeO2 nanoparticles to a conductive paste for forming an internal electrode layer, and adjusting the oxygen partial pressure to 10 -9 ~10 -10 The baking temperature can be controlled to 10 to 20 minutes.

[0049] The internal electrodes 121 and 122 may further include a conductive metal other than the Ni-Ge alloy described above. The conductive metal may include Ni, Cu, Ag, Pd, Au, alloys thereof, or combinations thereof.

[0050] In one embodiment, the average content of Ge relative to Ni in the entire internal electrodes 121, 122 may be 0.1 wt% to 10 wt%, for example, 0.5 wt% to 10 wt%, 0.5 wt% to 8 wt%, or 1 wt% to 8 wt%.

[0051] If the average weight percent of Ge relative to Ni in the entire internal electrodes 121, 122 is less than 0.1 weight percent, it may be difficult to improve the reliability of the capacitor and achieve a high capacitance.

[0052] If the average weight percentage of Ge relative to Ni in the entire internal electrodes 121 and 122 exceeds 10 weight percent, the melting point of the Ni--Ge alloy becomes too low, which may deteriorate the smoothness and connectivity of the internal electrodes.

[0053] According to the multilayer capacitor 100 of one embodiment, when the average content (weight %) of Ge relative to Ni at the center of the internal electrodes 121, 122 is X, and the average content (weight %) of Ge relative to Ni at a point 20 nm away from the interface between the internal electrodes 121, 122 and the dielectric layer 111 toward the center of the internal electrodes is Y, the relationship between X and Y satisfies the following formula 1. [Formula 1]

number

number

[0054] The center of the internal electrodes 121 and 122 may refer to a midpoint between a point on one surface of one of the internal electrodes and a point on the other surface of the internal electrodes located at a shortest distance from the point in a cross section cut in the L-axis and T-axis directions from the center in the W-axis direction of the capacitor body 110. Also, it may refer not only to the midpoint but also to a region within ±30% in the T-axis direction from the midpoint.

[0055] When the average content (weight %) of Ge relative to Ni at the center of the internal electrodes 121 and 122 is X, the value of X may be 0.90 weight % to 1.80 weight %, for example, 0.95 weight % to 1.80 weight %, 0.95 weight % to 1.60 weight %, or 0.95 weight % to 1.55 weight %.

[0056] The surface layer of the internal electrodes 121 and 122 may refer to a region other than the center of the internal electrodes, which is a point 20 nm away in the T-axis direction from the interface between the internal electrodes 121 and 122 and the dielectric layer 111 toward the center of the internal electrodes. Also, it may refer not only to the above-mentioned point, but also to a region within ±30% in the T-axis direction from the above-mentioned point.

[0057] When the average content (weight %) of Ge relative to Ni in the surface layer portion of the internal electrodes 121 and 122 is Y, the Y value may be 1.00 weight % to 1.50 weight %, for example, 1.10 weight % to 1.50 weight %, or 1.10 weight % to 1.30 weight %.

[0058] FIG. 4 is a TEM image showing the results of component analysis of the internal electrodes 121, 122 included in the multilayer capacitor 100 according to one embodiment, FIG. 5 is EDS mapping of Ni, and FIG. 6 is EDS mapping of Ge.

[0059] 4 to 6, the average weight percent of Ge relative to Ni contained in the internal electrodes 121 and 122 can be measured through a transmission electron microscope (TEM)-energy dispersion X-ray spectrometer (EDS) quantitative analysis.

[0060] As an example, the average weight percentage of Ge relative to Ni in the entire internal electrodes 121 and 122 can be determined by selecting five or more arbitrary internal electrodes, selecting arbitrary 10 points within the internal electrodes, quantitatively analyzing Ni and Ge using TEM-EDS, and calculating the arithmetic average of the measured values.

[0061] As an example, the average weight percentage of Ge relative to Ni at the center of the internal electrodes 121 and 122 can be obtained by selecting five or more arbitrary internal electrodes, selecting five equally spaced points corresponding to the center of the internal electrodes, quantitatively analyzing Ni and Ge using TEM-EDS, and calculating the arithmetic average of the measured values.

[0062] As an example, the average weight percentage of Ge relative to Ni in the surface layer of the internal electrodes 121 and 122 can be obtained by selecting five or more arbitrary internal electrodes, selecting five equally spaced points corresponding to points spaced about 20 nm apart from the interface between the internal electrodes and the dielectric layer toward the center of the internal electrodes, quantitatively analyzing Ni and Ge using TEM-EDS, and calculating the arithmetic average of the measured values.

[0063] The first internal electrode 121 and the second internal electrode 122 are electrodes having different polarities, and are alternately arranged so as to face each other along the T-axis direction with the dielectric layer 111 therebetween, and one end can be exposed through the third and fourth surfaces of the capacitor body 110, respectively.

[0064] The first internal electrode 121 and the second internal electrode 122 can be electrically insulated from each other by a dielectric layer 111 disposed therebetween.

[0065] 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 can be electrically connected to the first external electrode 131 and the second external electrode 132, respectively.

[0066] The first internal electrode 121 and the second internal electrode 122 may also contain dielectric particles of the same composition as the ceramic material contained in the dielectric layer 111 .

[0067] The first internal electrode 121 and the second internal electrode 122 may be formed using a conductive paste containing a conductive metal. The conductive paste may be printed by a screen printing method, a gravure printing method, or the like.

[0068] As an example, the average thickness of the first internal electrode 121 and the second internal electrode 122 may be 0.05 μm or more, 0.1 μm or more, 0.2 μm or more, or 0.25 μm or more, and may be 1 μm or less, 0.5 μm or less, 0.4 μm or less, or 0.3 μm or less.

[0069] The average thickness of the first internal electrode 121 or the second internal electrode 122 can be measured by the following method.

[0070] First, the stacked capacitor 100 is placed in an epoxy mixture and hardened, and then the sides of the capacitor body 110 in the L-axis and T-axis directions are polished to the 1 / 2 point in the W-axis direction, fixed, and maintained in a vacuum atmosphere chamber to prepare cross-sectional samples (hereinafter referred to as "cross-sectional samples") cut from the center of the capacitor body 110 in the W-axis direction in the L-axis and T-axis directions.

[0071] Thereafter, the cross-sectional sample is observed with a scanning electron microscope (SEM) to prepare a scanning electron microscope image.

[0072] From the scanning electron microscope (SEM) image of the cross-sectional sample, the average thickness of the internal electrodes can be obtained by calculating the arithmetic mean value of the thicknesses of the first internal electrode 121 or the second internal electrode 122 at 10 points spaced apart at a predetermined interval from the center point in the length direction (L-axis direction) or width direction (W-axis direction) of the first internal electrode 121 or the second internal electrode 122 as a reference point.

[0073] The intervals between the 10 points can be adjusted according to the scale of the scanning electron microscope (SEM) image, for example, the intervals can be 1 μm to 100 μm, 1 μm to 50 μm, or 1 μm to 10 μm.

[0074] 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 intervals between the 10 points can be adjusted.

[0075] The dielectric layer 111 contains a dielectric, and the dielectric can include a main component and a secondary component.

[0076] 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.

[0077] As an example, the main component is Ba m TiO3 (0.995 ≤ m ≤ 1.010), (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), (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 a dielectric material including a combination thereof.

[0078] As an example, the main components may 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 combinations thereof.

[0079] By way of example, the minor component may include dysprosium (Dy), vanadium (V), manganese (Mn), chromium (Cr), silicon (Si), aluminum (Al), magnesium (Mg), tin (Sn), antimony (Sb), germanium (Ge), gallium (Ga), indium (In), barium (Ba), lanthanum (La), yttrium (Y), actinium (Ac), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), hafnium (Hf), or combinations thereof.

[0080] The dielectric may further include a ceramic additive, an organic solvent, a binder, a dispersant, or a combination thereof.

[0081] As an example, the average thickness of the dielectric layer 111 can be 0.05 μm or more, 0.1 μm or more, or 0.2 μm or more, and can be 2.5 μm or less, 1.5 μm or less, 0.5 μm or less, or 0.4 μm or less.

[0082] When the average thickness of the dielectric layer 111 is less than 0.05 μm, it may be difficult to confirm the improvement in reliability. The average thickness of the dielectric layer 111 may be an arithmetic average value of the thicknesses of the dielectric layer 111 at 10 points spaced apart from the center point in the length direction (L-axis direction) or width direction (W-axis direction) of the dielectric layer 111 at a predetermined interval in a scanning electron microscope (SEM) image of the cross-sectional sample.

[0083] The interval between the 10 points can be adjusted according to the scale of a scanning electron microscope (SEM) image, and can be, for example, 1 μm to 100 μm, 1 μm to 50 μm, or 1 μm to 10 μm.

[0084] In this case, 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 spacing between the 10 points can be adjusted.

[0085] The first external electrode 131 and the second external electrode 132 are provided with voltages of different polarities and are electrically connected to the exposed portions of the first internal electrode 121 and the second internal electrode 122, respectively.

[0086] 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 stored between the opposing first internal electrode 121 and second internal electrode 122. At this time, the capacitance of the multilayer capacitor 100 is proportional to the overlap 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.

[0087] The first external electrode 131 and the second external electrode 132 are arranged on the third and fourth surfaces of the capacitor body 110, respectively, and may include first and second connection portions connecting to the first internal electrode 121 and the second internal electrode 122, and first and second band portions arranged at corners where the third and fourth surfaces of the capacitor body 110 meet the first and second surfaces or the fifth and sixth surfaces.

[0088] The first and second band portions may extend from the first and second connection portions to parts of the first and second faces or the fifth and sixth faces of the capacitor body 110. The first and second band portions may serve to improve the bonding strength between the first external electrode 131 and the second external electrode 132.

[0089] As an example, the first external electrode 131 and the second external electrode 132 may each include a sintered metal layer in contact with the capacitor body 110, a conductive resin layer arranged to cover the sintered metal layer, and a plating layer arranged to cover the conductive resin layer.

[0090] The sintered metal layer can include a conductive metal and glass.

[0091] As an example, the sintered metal layer may 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, and for example, copper (Cu) may include copper (Cu) alloys. When the conductive metal includes copper, the metal other than copper may be included in an amount of 5 molar parts or less relative to 100 molar parts of copper.

[0092] As an example, the sintered metal layer may include a composition in which an oxide is mixed with glass, and may be at least one 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 may be selected from the group consisting of zinc (Zn), titanium (Ti), copper (Cu), vanadium (V), manganese (Mn), iron (Fe), and nickel (Ni), the alkali metal may be selected from the group consisting of lithium (Li), sodium (Na), and potassium (K), and the alkaline earth metal may be at least one selected from the group consisting of magnesium (Mg), calcium (Ca), strontium (Sr), and barium (Ba).

[0093] Alternatively, the conductive resin layer may be formed on the sintered metal layer, for example, to completely cover the sintered metal layer. Meanwhile, the first external electrode 131 and the second external electrode 132 may not include a sintered metal layer, in which case the conductive resin layer may be in direct contact with the capacitor body 110.

[0094] The conductive resin layer extends on the first and second surfaces or the fifth and sixth surfaces of the capacitor body 110, and the length of the region (i.e., band portion) in which the conductive resin layer extends 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., band portion) in which the sintered metal layer extends on the first and second surfaces or the fifth and sixth surfaces of the capacitor body 110. That is, the conductive resin layer may be formed on the sintered metal layer to completely cover the sintered metal layer.

[0095] The conductive resin layer contains a resin and a conductive metal.

[0096] The resin contained in the conductive resin layer is not particularly limited as long as it has adhesive properties and impact absorbency and can be mixed with the conductive metal powder to form a paste, and can include, for example, phenolic resin, acrylic resin, silicone resin, epoxy resin, or polyimide resin.

[0097] The conductive metal contained in the conductive resin layer serves to electrically connect with the first internal electrode 121 and the second internal electrode 122 or the sintered metal layer.

[0098] The conductive metal contained in the conductive resin layer may have a spherical shape, a flake shape, or a combination thereof. That is, the conductive metal may be only flake-shaped, only spherical, or a mixture of flake-shaped and spherical shapes.

[0099] Here, the spherical shape may include a shape that is not completely spherical, for example, a shape in which the ratio of the major axis to the minor axis (major axis / minor axis) is 1.45 or less. The flake-type powder means a powder that is flat and has an elongated shape, and is not particularly limited, and may, for example, have a ratio of the major axis to the minor axis (major axis / minor axis) of 1.95 or more.

[0100] The first external electrode 131 and the second external electrode 132 may further include a plating layer disposed on the outer side of the conductive resin layer.

[0101] The plating layer may include nickel (Ni), copper (Cu), tin (Sn), palladium (Pd), platinum (Pt), gold (Au), silver (Ag), tungsten (W), titanium (Ti), lead (Pb), etc., alone or in combination. For example, the plating layer may be a nickel (Ni) plating layer or a tin (Sn) plating layer, or may be a layer in which a nickel (Ni) plating layer and a tin (Sn) plating layer are sequentially laminated, or a layer in which a tin (Sn) plating layer, a nickel (Ni) plating layer, and a tin (Sn) plating layer are sequentially laminated. The plating layer may also include a plurality of nickel (Ni) plating layers and / or a plurality of tin (Sn) plating layers.

[0102] The plating layer can improve the mountability of the multilayer capacitor 100 on a substrate, structural reliability, durability against the outside, heat resistance, and equivalent series resistance (ESR).

[0103] Specific examples of the present invention will be presented below. However, the examples described below are merely for the purpose of specifically illustrating and explaining the present invention, and are not intended to limit the scope of the present invention.

[0104] Working Example The contents of Ni and Ge contained in the internal electrode paste are adjusted, and the oxygen partial pressure conditions are adjusted to manufacture the multilayer capacitor. -9 ~10 -10 The oxygen partial pressure is controlled to about 0.25 μm, and the laminate is fired for about 10 minutes. In the laminate capacitor thus manufactured, the internal electrodes have an average thickness of 0.25 μm, and the dielectric layers have an average thickness of 1.0 μm.

[0105] Specifically, multilayer capacitors of Examples 1 to 7 and Comparative Examples 1 to 3 are manufactured, in which the average Ge content (wt %) relative to Ni in the entire internal electrodes is as shown in Table 2 below.

[0106] In addition, the average content (wt%) of Ge relative to Ni in the entire internal electrode is 3.5wt%,

number

[0107] For reference, Table 1 below shows the average Ge content (X) relative to Ni in the center of the internal electrode and the average Ge content (Y) relative to Ni in the surface layer of the internal electrode, measured for five randomly selected internal electrodes, and their averages.

[0108] [Table 1]

[0109] Evaluation example Evaluation example 1: MTTF (Mean Time To Failure) measurement A high temperature load test is carried out on 400 samples for each of the examples and comparative examples under conditions of 125° C. and 8 V, and the MTTF (Mean Time To Failure) value is measured.

[0110] At this time, the time when the insulation resistance became 10 kΩ or less was defined as a fixed time, and the MTTF value of Comparative Example 1 in Tables 2 and 3 was defined as Reference Value 1, and the relative values ​​of the other Examples and Comparative Examples were listed.

[0111] Evaluation example 2: Capacitance The capacitance was measured using an LCR meter at 1 kHz and AC 0.5 V. Table 2 shows the capacitance of Comparative Example 1 as reference value 1, and the relative values ​​of the other examples and comparative examples.

[0112] [Table 2]

[0113] Referring to Table 2, Comparative Example 1 does not contain a Ni--Ge alloy containing Ge in the internal electrodes, and Comparative Examples 2 and 3 correspond to cases in which the internal electrodes contain excessive Ge.

[0114] Referring to Table 2, it can be seen that the multilayer capacitors of Examples 1 to 7 have higher capacitance, higher MTTF values, and better reliability than those of Comparative Examples 1 to 3.

[0115] [Table 3]

[0116] Referring to Table 3,

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[0117] Although the preferred embodiment of the present invention has been described above, the present invention is not limited thereto, and various modifications can be made within the scope of the claims, the summary of the invention, and the accompanying drawings, which also fall within the scope of the present invention. [Explanation of symbols]

[0118] 100 Stacked Capacitor 110 Capacitor Body 111 Dielectric layer 112, 113 Coverage area 121 1st internal electrode 122 2nd internal electrode 131 1st external electrode 132 2nd external electrode

Claims

1. a capacitor body including a dielectric layer and an internal electrode; an external electrode disposed on an outer side of the capacitor body; the internal electrodes include a Ni-Ge alloy; A multilayer capacitor, in which the relationship between X and Y satisfies the following formula 1, where X is an average content (wt%) of Ge relative to Ni at the center of the internal electrode, and Y is an average content (wt%) of Ge relative to Ni at a point 20 nm away from an interface between the internal electrode and the dielectric layer toward the center of the internal electrode: [Formula 1] [0010]

2. 2. The multilayer capacitor according to claim 1, wherein an average content (wt%) of Ge relative to Ni in the entire internal electrodes is 0.1 wt% to 10 wt%.

3. 2. The multilayer capacitor according to claim 1, wherein the X value is 0.90% by weight to 1.80% by weight.

4. 2. The multilayer capacitor according to claim 1, wherein the Y value is 1.00% by weight to 1.50% by weight.

5. 2. The multilayer capacitor according to claim 1, wherein the internal electrodes have an average thickness of 0.05 μm to 1 μm.

6. 2. The multilayer capacitor according to claim 1, wherein the average thickness of the dielectric layer is 0.05 μm to 2.5 μm.

7. The multilayer capacitor according to claim 1 , wherein the dielectric layer includes a dielectric material including a main component and a subcomponent.

8. The main component is Ba. ｍ TiO ３ (0.995≦m≦1.010), (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), (Ba １－ｘ Ca ｘ ) ｍ (Ti １－ｙ Sn ｙ ) O ３ 8. The stacked capacitor of claim 7, comprising: (0.995≦m≦1.010, 0≦x≦0.10, 0<y≦0.20), or a combination thereof.

9. The stacked capacitor according to claim 7, wherein the minor component includes dysprosium (Dy), vanadium (V), manganese (Mn), chromium (Cr), silicon (Si), aluminum (Al), magnesium (Mg), tin (Sn), antimony (Sb), germanium (Ge), gallium (Ga), indium (In), barium (Ba), lanthanum (La), yttrium (Y), actinium (Ac), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), hafnium (Hf), or a combination thereof.

10. a capacitor body including a dielectric layer and an internal electrode; an external electrode disposed on an outer side of the capacitor body; the internal electrodes include a Ni-Ge alloy; The average content (wt%) of Ge relative to Ni in the entire internal electrode is 0.1 wt% to 10 wt%, A multilayer capacitor, in which the relationship between X and Y satisfies the following formula 1, where X is an average content (wt%) of Ge relative to Ni at the center of the internal electrode, and Y is an average content (wt%) of Ge relative to Ni at a point 20 nm away from an interface between the internal electrode and the dielectric layer toward the center of the internal electrode: [Formula 1] [0025]

11. 11. The multilayer capacitor according to claim 10, wherein the X value is 0.90% by weight to 1.80% by weight.

12. 11. The multilayer capacitor according to claim 10, wherein the Y value is 1.00% by weight to 1.50% by weight.

13. The multilayer capacitor according to claim 10, wherein the internal electrodes have an average thickness of 0.05 μm to 1 μm.

14. 11. The multilayer capacitor according to claim 10, wherein the average thickness of the dielectric layer is 0.05 μm to 2.5 μm.

15. The multilayer capacitor according to claim 10 , wherein the dielectric layer includes a dielectric material including a main component and a subcomponent.

16. The main component is Ba. ｍ TiO ３ (0.995≦m≦1.010), (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), (Ba １－ｘ Ca ｘ ) ｍ (Ti １－ｙ Sn ｙ ) O ３ 16. The stacked capacitor of claim 15, comprising: (0.995≦m≦1.010, 0≦x≦0.10, 0<y≦0.20), or a combination thereof.

17. 16. The stacked capacitor according to claim 15, wherein the minor component includes dysprosium (Dy), vanadium (V), manganese (Mn), chromium (Cr), silicon (Si), aluminum (Al), magnesium (Mg), tin (Sn), antimony (Sb), germanium (Ge), gallium (Ga), indium (In), barium (Ba), lanthanum (La), yttrium (Y), actinium (Ac), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), hafnium (Hf), or a combination thereof.

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