Multilayer electronic component

Abstract

To provide a multilayer electronic component in which the moisture resistance reliability and the bending strength are improved.SOLUTION: A multilayer electronic component 100 includes a main body 110 including dielectric layers 111 and internal electrodes 121 and 122 disposed alternately with the dielectric layers, and external electrodes 131 and 132 including connection parts P1a and P2a disposed on third and fourth surfaces of the main body facing each other in a second direction and band parts P1b and P2b extending to a part of first and second surfaces of the main body facing each other in a first direction from the connection parts. The external electrode includes lower electrode layers 131a and 132a disposed in the connection parts and the band parts and in contact with the internal electrodes, internal electrode layers 131b and 132b disposed in the band parts and disposed on the lower electrode layers, and upper electrode layers 131c and 132c in contact with the lower electrode layers in the connection parts and in contact with the intermediate electrode layers in the band parts. The lower electrode layer contains Cu and the intermediate electrode layer contains Ag. At the interface between the lower electrode layer and the intermediate electrode layer, an alloy layer containing a Cu-Ag alloy is disposed.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a multilayer electronic component. [Background technology]

[0002] Multi-layered ceramic capacitors (MLCCs), which are one type of multi-layered electronic component, are chip-type capacitors that are mounted on printed circuit boards of various electronic products, such as visual devices such as liquid crystal displays (LCDs) and plasma display panels (PDPs), computers, smartphones, and mobile phones, and serve to charge and discharge electricity. Multi-layered ceramic capacitors can be used as components of various electronic devices due to their advantages of being small in size, high capacity, and easy to mount.

[0003] Recently, the external electrodes have been made thinner in order to miniaturize multilayer ceramic capacitors. However, the thinner the external electrodes, the easier it is for moisture and plating solution from the outside to penetrate into the main body. In addition, the thinner the external electrodes, the easier it is for cracks to occur in the multilayer ceramic capacitor due to bending stress generated during mounting.

[0004] Therefore, there is a need for research into the structure of external electrodes that can block the moisture penetration path that has become shorter due to the thinning of the external electrodes, prevent deterioration of the moisture resistance reliability of the multilayer ceramic capacitor, and improve the bending strength of the multilayer ceramic capacitor. Summary of the Invention [Problem to be solved by the invention]

[0005] One of several objects of the present invention is to improve the moisture resistance reliability and bending strength of a multilayer electronic component.

[0006] One of several objects of the present invention is to improve the capacitance and ESR characteristics of multilayer electronic components.

[0007] However, the scope of the present invention is not limited to the above, and can be more easily understood in the course of describing specific embodiments of the present invention. [Means for solving the problem]

[0008] One embodiment of the present invention provides a multilayer electronic component including: a main body including dielectric layers and internal electrodes arranged alternately with the dielectric layers, the main body including first and second sides facing in a first direction, third and fourth sides connected to the first and second sides and facing in the second direction, and fifth and sixth sides connected to the first, second, third and fourth sides and facing in the third direction; and an external electrode including connection portions arranged on the third and fourth sides, and a band portion extending from the connection portions to parts of the first and second sides, the external electrode including a lower electrode layer in contact with the internal electrodes and arranged on the connection portions and the band portion, an intermediate electrode layer arranged on the band portion and on the lower electrode layer, and an upper electrode layer in contact with the lower electrode layer at the connection portions and in contact with the intermediate electrode layer at the band portion, the lower electrode layer including Cu, the intermediate electrode layer including Ag, and an alloy layer including a Cu-Ag alloy arranged at the interface between the lower electrode layer and the intermediate electrode layer.

[0009] One embodiment of the present invention provides a multilayer electronic component including: a main body including dielectric layers and internal electrodes arranged alternately with the dielectric layers, the main body including first and second sides facing in a first direction, third and fourth sides connected to the first and second sides and facing in the second direction, and fifth and sixth sides connected to the first, second, third and fourth sides and facing in the third direction; and an external electrode including connection portions arranged on the third and fourth sides, and a band portion extending from the connection portions to portions of the first and second sides, the external electrode including a lower electrode layer in contact with the internal electrodes and arranged in the connection portions and the band portion, an intermediate electrode layer arranged in the band portion and on the lower electrode layer, and an upper electrode layer in contact with the lower electrode layer at the connection portions and in contact with the intermediate electrode layer at the band portion, the lower electrode layer including a first metal mainly containing Cu, and the intermediate electrode layer including a second metal mainly containing Ag. Effect of the Invention

[0010] One of the various effects of the present invention is that it is possible to improve the moisture resistance reliability and bending strength of a multilayer electronic component.

[0011] One of the various effects of the present invention is that it can improve the capacitance and ESR characteristics of a multilayer electronic component. [Brief description of the drawings]

[0012] [Figure 1] 1 is a perspective view showing a schematic configuration of a multilayer electronic component according to an embodiment of the present invention; [Diagram 2] FIG. 2 is an exploded perspective view showing a schematic view of the main body of FIG. [Diagram 3] 2 is a cross-sectional view that shows a schematic cross section taken along line II in FIG. 1. [Figure 4] 2 is a cross-sectional view that shows a schematic cross section taken along line II-II' in FIG. 1. [Diagram 5] FIG. 4 is an enlarged view of a K1 region in FIG. [Figure 6] FIG. 4 is a cross-sectional view showing a schematic configuration of a multilayer electronic component according to another embodiment of the present invention, which is a modification of FIG. 3. [Figure 7] FIG. 4 is a cross-sectional view showing a schematic configuration of a multilayer electronic component according to another embodiment of the present invention, which is a modification of FIG. 3. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, the embodiments of the present invention will be described with reference to specific embodiments and the accompanying drawings. However, the embodiments of the present invention can be modified into various other forms, and the scope of the present invention is not limited to the embodiments described below. Furthermore, the embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art. Therefore, the shape and size of elements in the drawings may be exaggerated for clearer explanation, and elements indicated by the same reference numerals in the drawings are the same elements.

[0014] In order to clearly explain the present invention in the drawings, parts that are not relevant to the explanation are omitted, and the size and thickness of each component shown in the drawings are arbitrarily shown for convenience of explanation, so the present invention is not necessarily limited to those shown in the drawings. Components having the same function within the same concept are described using the same reference numerals. Furthermore, throughout the specification, when a part is said to "include" a certain component, this does not mean that other components are excluded, but that the part may further include other components, unless otherwise specified.

[0015] In the drawings, the first direction can be defined as a thickness T direction, the second direction can be defined as a length L direction, and the third direction can be defined as a width W direction.

[0016] Multilayer Electronic Components FIG. 1 is a perspective view that shows a schematic view of a multilayer electronic component according to one embodiment of the present invention, FIG. 2 is an exploded perspective view that shows a schematic view of a main body of FIG. 1, FIG. 3 is a cross-sectional view that shows a schematic view of a cut section taken along line II of FIG. 1, FIG. 4 is a cross-sectional view that shows a schematic view of a cut section taken along line II-II' of FIG. 1, and FIG. 5 is an enlarged view of area K1 of FIG. 3.

[0017] A multilayer electronic component 100 according to one embodiment of the present invention will be described in detail below with reference to Figures 1 to 5. Also, a multilayer ceramic capacitor will be described as an example of the multilayer electronic component, but the present invention is not limited thereto and can be applied to various multilayer electronic components such as inductors, piezoelectric elements, varistors, thermistors, etc.

[0018] A multilayer electronic component 100 according to one embodiment of the present invention includes a body 110 including a dielectric layer 111 and internal electrodes 121 and 122 , and external electrodes 131 and 132 .

[0019] Although there is no particular limitation on the specific shape of the body 110, the body 110 may be hexahedral or a similar shape as shown in the figure. Due to shrinkage of the ceramic powder contained in the body 110 during the firing process and grinding of the edges, the body 110 may not have a hexahedral shape with perfect straight lines, but may have a substantially hexahedral shape.

[0020] The main body 110 may have a first surface 1 and a second surface 2 facing in a first direction, a third surface 3 and a fourth surface 4 connected to the first surface 1 and the second surface 2 and facing in the second direction, and a fifth surface 5 and a sixth surface 6 connected to the first surface 1, the second surface 2, the third surface 3 and the fourth surface 4 and facing in the third direction.

[0021] The body 110 may include dielectric layers 111 and internal electrodes 121, 122 alternately arranged with the dielectric layers 111. The plurality of dielectric layers 111 forming the body 110 may be in a sintered state, and the boundaries between adjacent dielectric layers 111 may be integrated to such an extent that they are difficult to see without using a scanning electron microscope (SEM).

[0022] The dielectric layer 111 can be formed by manufacturing a ceramic slurry containing ceramic powder, an organic solvent, and a binder, applying and drying the slurry on a carrier film to provide a ceramic green sheet, and then firing the ceramic green sheet. The ceramic powder is not particularly limited as long as sufficient capacitance can be obtained. For example, a barium titanate-based material, a lead composite perovskite-based material, a strontium titanate-based material, or the like can be used. As an example of the ceramic powder, BaTiO 3 、BaTiO 3 in which Ca (calcium), Zr (zirconium), etc. are partially solid-solved (Ba 1-x Ca x )TiO 3 (0 < x < 1), Ba(Ti 1-y Ca y )O 3 (0 < y < 1), (Ba 1-x Ca x )(Ti 1-y Zr y )O 3 (0 < x < 1, 0 < y < 1) or Ba(Ti 1-y Zr y )O 3 (0 < y < 1), etc. can be mentioned. Ethanol or the like can be used as the organic solvent, polyvinyl butyral or the like can be used as the binder, and known substances used in the art can be used as the organic solvent and the binder.

[0023] The internal electrodes 121 and 122 can include a first internal electrode 121 and a second internal electrode 122 that are alternately arranged in the first direction with the dielectric layer 111 interposed therebetween. That is, the first internal electrode 121 and the second internal electrode 122, which are a pair of electrodes having different polarities, can be arranged to face each other with the dielectric layer 111 interposed therebetween. The first internal electrode 121 and the second internal electrode 122 can be electrically separated from each other by the dielectric layer 111 disposed therebetween.

[0024] The first internal electrode 121 may be spaced apart from the fourth surface 4 and connected to the first external electrode 131 on the third surface 3 side. The second internal electrode 122 may be spaced apart from the third surface 3 and connected to the second external electrode 132 on the fourth surface 4 side.

[0025] The conductive metal contained in the internal electrodes 121, 122 may be one or more of Ni, Cu, Pd, Ag, Au, Pt, Sn, W, Ti, and alloys thereof, and more preferably may include Ni, but the present invention is not limited thereto.

[0026] The internal electrodes 121 and 122 may be formed by applying a conductive paste for internal electrodes containing a conductive metal to a predetermined thickness on the ceramic green sheet and firing the same. The method for printing the conductive paste for internal electrodes may be a screen printing method or a gravure printing method, but the present invention is not limited thereto.

[0027] The average thickness td of the dielectric layer 111 and the average thickness te of the internal electrodes 121, 122 do not need to be particularly limited. The average thickness td of the dielectric layer 111 and the average thickness te of the internal electrodes 121, 122 can be set arbitrarily according to the desired characteristics and applications. However, in order to achieve a small size and high capacity of the multilayer electronic component 100, the average thickness td of the dielectric layer 111 may be 0.3 μm or more and 10 μm or less, and the average thickness te of the internal electrodes 121, 122 may be 0.3 μm or more and 1 μm or less. In general, the thinner the thickness of the dielectric layer 111 and the internal electrodes 121, 122, the more likely the reliability characteristics of the multilayer electronic component 100, such as the insulation resistance and the breakdown voltage, may be reduced. However, the external electrodes 131, 132 of the multilayer electronic component 100 according to one embodiment of the present invention have a multilayer structure described later, so that the reliability of the multilayer electronic component 100 can be ensured even when the average thickness td of the dielectric layer 111 and the average thickness te of the internal electrodes 121, 122 satisfy the above ranges.

[0028] The average thickness td of the dielectric layer 111 and the average thickness te of the internal electrodes 121, 122 refer to the average size of the dielectric layer 111 and the internal electrodes 121, 122 in the first direction, respectively. The average thickness td of the dielectric layer 111 and the average thickness te of the internal electrodes 121, 122 can be measured by scanning the cross sections of the body 110 in the first direction and the second direction with a scanning electron microscope (SEM) with a magnification of 10,000. More specifically, the average thickness td of the dielectric layer 111 can be measured by measuring the thickness at a number of points, for example, 30 points that are equally spaced in the second direction, of one dielectric layer 111, and then averaging the thicknesses. In addition, the average thickness te of the internal electrodes 121, 122 can be measured by measuring the thickness at a number of points, for example, 30 points that are equally spaced in the second direction, of one internal electrode 121, 122, and then averaging the thicknesses. The 30 equally spaced points can be specified by the capacitance forming portion Ac. Meanwhile, by measuring such average values ​​for 10 dielectric layers 111 and 10 internal electrodes 121, 122, respectively, and then measuring the average values, the average thickness td of the dielectric layers 111 and the average thickness te of the internal electrodes 121, 122 can be further generalized.

[0029] The body 110 may include a capacitance forming part Ac that is disposed inside the body 110 and includes first internal electrodes 121 and second internal electrodes 122 that are alternately disposed with a dielectric layer 111 therebetween to form a capacitance, and a first cover part 112 and a second cover part 113 that are disposed on both sides of the capacitance forming part Ac facing each other in a first direction. The cover parts 112 and 113 may basically serve to prevent damage to the internal electrodes due to physical or chemical stress. The cover parts 112 and 113 may have a similar configuration to the dielectric layer 111, except that they do not include internal electrodes.

[0030] The average thickness tc of the cover parts 112, 113 does not need to be particularly limited. The average thickness tc of the cover parts 112, 113 may be, for example, 300 μm or less. Alternatively, the average thickness tc of the cover parts 112, 113 may be 1% to 20% of the maximum size of the multilayer electronic component 100 in the first direction. Here, the average thickness tc of the cover parts 112, 113 means the average thickness of each of the first cover part 112 and the second cover part 113.

[0031] The average thickness tc of the cover parts 112, 113 may mean the average size in the first direction of the cover parts 112, 113, and may be the average value of the size in the first direction measured at five points equally spaced in the second direction in a cross section in the first and second directions passing through the center of the body 110 in the third direction.

[0032] The body 110 may include a first margin portion 114 and a second margin portion 115 disposed on both sides of the capacitance forming portion Ac facing the third direction. That is, the margin portions 114 and 115 may refer to regions between both ends of the internal electrodes 121 and 122 and the boundary surface of the body 110 in a cross section obtained by cutting the body 110 in the first and third directions.

[0033] The margin portions 114 and 115 may have a similar configuration to the dielectric layer 111, except that they do not include the internal electrodes 121 and 122. The margin portions 114 and 115 may essentially serve to prevent damage to the internal electrodes 121 and 122 due to physical or chemical stress.

[0034] The margin portions 114, 115 may be formed by applying a conductive paste for internal electrodes to the ceramic green sheet and firing it, except for the portions where the margin portions are to be formed. Alternatively, in order to suppress steps due to the internal electrodes 121, 122, the margin portions 114, 115 may be formed by cutting the laminated internal electrodes 121, 122 so as to be exposed on the fifth surface 5 and the sixth surface 6 of the main body, and then laminating a single dielectric layer or two or more dielectric layers on both surfaces of the capacitance forming portion Ac facing the third direction.

[0035] The average thickness tm of the margin portions 114, 115 does not need to be particularly limited. The average thickness tm of the margin portions 114, 115 may be, for example, 400 μm or less. Alternatively, the average thickness tm of the margin portions 114, 115 may be 1% to 15% of the maximum size of the multilayer electronic component 100 in the third direction. Here, the average thickness tm of the margin portions 114, 115 means the average thickness of each of the first margin portion 114 and the second margin portion 115.

[0036] The average thickness tm of the margin portions 114, 115 may mean the average size in the third direction of the margin portions 114, 115, and may be the average value of the sizes in the third direction measured at five points equally spaced in the first direction in a cross section in the first and third directions passing through the center of the body 110 in the second direction.

[0037] The external electrodes 131, 132 may be disposed on the third surface 3 and the fourth surface 4 of the body 110, and may extend onto parts of the first surface 1, the second surface 2, the fifth surface 5, and the sixth surface 6. The external electrodes 131, 132 may include a first external electrode 131 connected to the first internal electrode 121 and a second external electrode 132 connected to the second internal electrode 122. Hereinafter, a structure in which the multilayer electronic component 100 has two external electrodes 131, 132 will be described, but the present invention is not limited thereto, and the number, shape, etc. of the external electrodes 131, 132 may be changed according to the shape of the internal electrodes 121, 122 or other purposes.

[0038] The external electrodes 131, 132 may include connection portions P1a, P2a disposed on the third surface 3 and the fourth surface 4, and band portions P1b, P2b extending from the connection portions P1a, P2a to parts of the first surface 1 and the second surface 2. The band portions P1b, P2b may also extend from the connection portions P1a, P2a to parts of the fifth surface 5 and the sixth surface 6. In addition, the external electrodes 131, 132 may include corner portions P1c, P2c disposed between the connection portions P1a, P2a and the band portions P1b, P2b. The corner portions P1c, P2c may be disposed on edges of the main body 110.

[0039] That is, the first external electrode 131 may include a first connection portion P1a arranged on the third surface 3, a first band portion P1b extending from the first connection portion P1a to a portion of the first surface 1 and the second surface 2, and a first corner portion P1c arranged between the first connection portion P1a and the first band portion P1b.

[0040] The second external electrode 132 may include a second connection portion P2a arranged on the fourth surface 4, a second band portion P2b extending from the second connection portion P2a to a portion of the first surface 1 and the second surface 2, and a second corner portion P2c arranged between the second connection portion P2a and the second band portion P2b.

[0041] The external electrodes 131, 132 may include lower electrode layers 131a, 132a in contact with the internal electrodes 121, 122 and disposed at the connection parts P1a, P2a and the band parts P1b, P2b, intermediate electrode layers 131b, 132b disposed at the band parts P1b, P2b and disposed on the lower electrode layers 131a, 132a, and upper electrode layers 131c, 132c in contact with the lower electrode layers 131a, 132a at the connection parts P1a, P2a and in contact with the intermediate electrode layers 131b, 132b at the band parts P1b, P2b. The upper electrode layers 131c, 132c may be disposed on the lower electrode layers 131a, 132a and the intermediate electrode layers 131b, 132b.

[0042] That is, the first external electrode 131 may include a first lower electrode layer 131a in contact with the first internal electrode 121 and arranged in the first connection portion P1a and the first band portion P1b, a first intermediate electrode layer 131b arranged in the first band portion P1b and arranged on the first lower electrode layer 131a, and a first upper electrode layer 131c in contact with the first lower electrode layer 131a at the first connection portion P1a and in contact with the first intermediate electrode layer 131b in the first band portion P1b.

[0043] The second external electrode 132 may include a second lower electrode layer 132a in contact with the second internal electrode 122 and arranged in the second connection portion P2a and the second band portion P2b, a second intermediate electrode layer 132b arranged in the second band portion P2b and arranged on the second lower electrode layer 132a, and a second upper electrode layer 132c in contact with the second lower electrode layer 132a at the second connection portion P2a and in contact with the second intermediate electrode layer 132b in the second band portion P2b.

[0044] The lower electrode layers 131a and 132a may include Cu. The lower electrode layers 131a and 132a may include glass. The glass included in the lower electrode layers 131a and 132a may include one or more oxides of Ba, Ca, Zn, Al, B, and Si, but the present invention is not limited thereto.

[0045] The lower electrode layers 131a and 132a may contain a first metal containing Cu as a main component. Here, "the first metal containing Cu as a main component" may mean that the content of Cu in the total content (at%) of elements constituting the first metal exceeds 50 at%.

[0046] The lower electrode layers 131a and 132a may contain Cu as a main component. For example, when a cross section in the first direction and a cross section in the second direction passing through the center in the third direction of the multilayer electronic component 100 are analyzed by a scanning electron microscope (SEM) and an energy dispersive spectroscopy (EDS), the ratio of an area occupied by Cu to a total area of ​​the lower electrode layers 131a and 132a may be 80% or more. For example, in the cross sections in the first direction and the second direction passing through the center in the third direction of the multilayer electronic component 100, the ratio of an area occupied by Cu to a total area of ​​the lower electrode layers 131a and 132a may be greater than the ratio of an area occupied by the remaining elements other than Cu to a total area of ​​the lower electrode layers 131a and 132a. Here, the total area of ​​the lower electrode layers 131a and 132a may mean the total area occupied by the lower electrode layers 131a and 132a in an image analyzed by SEM-EDS. The above image may be an image showing the entire lower electrode layers 131a and 132a, or may be an image showing an enlarged portion of the lower electrode layers 131a and 132a. Meanwhile, during analysis using energy dispersive spectroscopy (EDS), Cu is sometimes detected in the lower electrode layers 131a and 132a, but Ag is sometimes not detected.

[0047] The Cu metal component included in the lower electrode layers 131a, 132a may serve to electrically connect the internal electrodes 121, 122 to the external electrodes 131, 132. The glass included in the lower electrode layers 131a, 132a may serve to improve the density of the lower electrode layers 131a, 132a. The lower electrode layers 131a, 132a may be formed by dipping the third surface 3 and the fourth surface 4 of the body 110 into a conductive paste for the lower electrode layer including Cu powder, glass, a binder, an organic solvent, etc., and then firing the conductive paste for the lower electrode layer.

[0048] The intermediate electrode layers 131b and 132b may include Ag. The intermediate electrode layers 131b and 132b may include glass. The glass included in the intermediate electrode layers 131b and 132b may include one or more oxides of Ba, Ca, Zn, Al, B, and Si, but the present invention is not limited thereto.

[0049] The intermediate electrode layers 131b and 132b may contain a second metal containing Ag as a main component. Here, "the second metal containing Ag as a main component" may mean that the content of Ag in the total content (at%) of the elements constituting the second metal exceeds 50 at%.

[0050] The intermediate electrode layers 131b and 132b may include Ag as a main component. For example, when a cross section in the first direction and a cross section in the second direction passing through the center in the third direction of the multilayer electronic component 100 are analyzed by a scanning electron microscope (SEM) and an energy dispersive spectroscopy (EDS), a ratio of an area occupied by Ag to a total area of ​​the intermediate electrode layers 131b and 132b may be 80% or more. For example, in the cross sections in the first direction and the second direction passing through the center in the third direction of the multilayer electronic component 100, a ratio of an area occupied by Ag to a total area of ​​the intermediate electrode layers 131b and 132b may be greater than a ratio of an area occupied by the remaining elements other than Ag to a total area of ​​the intermediate electrode layers 131b and 132b. Here, the total area of ​​the intermediate electrode layers 131b and 132b may mean a total area occupied by the intermediate electrode layers 131b and 132b in an image analyzed by SEM-EDS. The above image may be an image showing the entire intermediate electrode layers 131b and 132b, or may be an image showing an enlarged portion of the intermediate electrode layers 131b and 132b. On the other hand, when an analysis is performed using energy dispersive spectroscopy (EDS), Ag is sometimes detected in the intermediate electrode layers 131b and 132b, but Cu is not sometimes detected.

[0051] The intermediate electrode layers 131b, 132b are basically disposed on the band portions P1b, P2b of the external electrodes 131, 132, and can play a role of improving the bending strength of the multilayer electronic component 100. There is no need to particularly limit the method of forming the intermediate electrode layers 131b, 132b. For example, the body 110 on which the lower electrode layers 131a, 132a are formed is dipped into a conductive paste for the intermediate electrode layer containing Ag powder, glass, a binder, an organic solvent, etc., and the conductive paste for the intermediate electrode layer applied to the connection portions P1a, P2a is removed, and then the paste for the intermediate electrode layer applied to the band portions P1b, P2 is fired to form the intermediate electrode layers 131b, 132b. The firing process for forming the intermediate electrode layers 131b, 132b may be performed at a temperature of 300° C. to 800° C., but the present invention is not limited thereto.

[0052] The type of the upper electrode layers 131c, 132c does not need to be particularly limited. The upper electrode layers 131c, 132c may be, for example, a plating layer for improving mounting characteristics. The upper electrode layers 131c, 132c may be, for example, a plating layer containing Ni, Sn, Pd and / or an alloy containing these, and may be formed of a plurality of layers. The upper electrode layers 131c, 132c may be, for example, a Ni plating layer and a Sn plating layer. More preferably, the upper electrode layers 131c, 132c may include a Ni plating layer and a Sn plating layer disposed on the Ni plating layer.

[0053] The upper electrode layers 131c and 132c can be formed by, for example, electrolytic plating and / or electroless plating, but the present invention is not limited to this.

[0054] Meanwhile, alloy layers 131d, 132d including a Cu-Ag alloy may be disposed at the interface between the lower electrode layers 131a, 132a and the intermediate electrode layers 131b, 132b. That is, the first external electrode 131 may include a first alloy layer 131d disposed at the interface between the first lower electrode layer 131a and the first intermediate electrode layer 131b. The second external electrode 132 may include a second alloy layer 132d disposed at the interface between the second lower electrode layer 132a and the second intermediate electrode layer 132b. The alloy layers 131d, 132d may be formed by mutual reaction between Cu of the lower electrode layers 131a, 132a and Ag of the intermediate electrode layers 131b, 132b when the intermediate electrode layers 131b, 132b are formed by firing a conductive paste. The alloy layers 131d, 132d may be disposed continuously or discontinuously at the interfaces between the lower electrode layers 131a, 132a and the intermediate electrode layers 131b, 132b.

[0055] The Cu-Ag alloy contained in the alloy layers 131d, 132d may contain oxygen (O). When analyzed using energy dispersive spectroscopy (EDS), Cu, Ag, and O may all be detected in the alloy layers 131d, 132d. In one embodiment, the molar ratio of Cu to Ag (Cu / Ag) may be 5 or more and 60 or less in at least a portion of the alloy layers 131d, 132d.

[0056] The lower electrode layers 131a, 132a and the intermediate electrode layers 131b, 132b are formed by firing a conductive paste and include a number of pores, and the alloy layers formed by the reaction between the lower electrode layers 131a, 132a and the intermediate electrode layers 131b, 132b may also include pores. However, in one embodiment, the average size of the pores included in the alloy layers 131d, 132d may be smaller than the average size of the pores included in the intermediate electrode layers 131b, 132b. Also, the average size of the pores included in the alloy layers 131d, 132d may be smaller than the average size of the pores included in the lower electrode layers 131a, 132a. Since the alloy layers 131d, 132d are denser than the lower electrode layers 131a, 132a and the intermediate electrode layers 131b, 132b, it is possible to effectively prevent moisture or a plating solution from the outside from penetrating into the body 110. Furthermore, by disposing the alloy layers 131d and 132d on the band portions P1b and P2b, the bending strength of the multilayer electronic component 100 can be improved.

[0057] Meanwhile, the alloy layers 131d, 132d can prevent the penetration of moisture from the outside and improve the bending strength of the multilayer electronic component 100, but if the alloy layers 131d, 132d completely cover the lower electrode layers 131a, 132a, an increase in resistance can cause a problem of a decrease in the capacitance of the multilayer electronic component 100 and an increase in ESR. In contrast, according to one embodiment of the present invention, the lower electrode layers 131a, 132a and the upper electrode layers 131c, 132c can be in contact with each other at the connection portions P1a, P2a, thereby reducing the resistance caused by the alloy layers 131d, 132d and improving the electrical characteristics of the multilayer electronic component 100.

[0058] The thickness of the alloy layers 131d and 132d does not need to be particularly limited. However, in one embodiment, when the thickness of the central region in the second direction of the intermediate electrode layers 131b and 132b in the first and second direction cross sections passing through the center in the third direction of the main body 110 is t1 and the thickness of the central region in the second direction of the alloy layers 131d and 132d is t2, t1>t2 can be satisfied. That is, in the band parts P1b and P2b, the thickness of the intermediate electrode layers 131b and 132b can be larger than the thickness of the alloy layers 131d and 132d. The above t1 and t2 do not need to be particularly limited, but the above t1 may be 1 μm to 100 μm, and the above t2 may be 0.01 μm to 50 μm.

[0059] The intermediate electrode layers 131b and 132b may be disposed in the band portions P1b and P2b, and the specific structure of the intermediate electrode layers 131b and 132b may vary depending on the desired characteristics of the multilayer electronic component 100.

[0060] In one embodiment, the intermediate electrode layers 131b, 132b may be disposed so as to cover the ends of the lower electrode layers 131a, 132a in the band portions P1b, P2b. This allows the alloy layers 131d, 132d to be disposed on the ends of the lower electrode layers 131a, 132a. By having the alloy layers 131d, 132d cover the ends of the lower electrode layers 131a, 132a, which serve as a permeation path for external moisture, the moisture resistance reliability of the multilayer electronic component 100 can be more effectively improved.

[0061] In one embodiment, one end of the intermediate electrode layers 131b, 132b may be disposed at the corner portions P1c, P2c. That is, one end of the first intermediate electrode layer 131b may be disposed at the first corner portion P1c, and one end of the second intermediate electrode layer 131c may be disposed at the second corner portion P2c. As a result, one ends of the alloy layers 131d, 132d may be disposed at the corner portions P1c, P2c. By disposing one ends of the alloy layers 131d, 132d at the corner portions P1c, P2c, it is possible to effectively prevent moisture from penetrating from the outside through the edge of the main body 110, which is vulnerable to moisture penetration.

[0062] In one embodiment, the intermediate electrode layers 131b, 132b do not need to be disposed at the connection portions P1a, P2a, which ensures a sufficient bonding area between the lower electrode layers 131a, 132a and the upper electrode layers 131c, 132c, thereby reducing the resistance caused by the formation of the alloy layers 131d, 132d and effectively improving the electrical characteristics of the multilayer electronic component 100.

[0063] Fig. 6 is a cross-sectional view that illustrates a multilayer electronic component 200 according to another embodiment of the present invention, which is a modified example of Fig. 3. The multilayer electronic component 200 according to another embodiment of the present invention will be described below with reference to Fig. 6, but descriptions that overlap with those of the multilayer electronic component 100 according to the above-described embodiment of the present invention will be omitted.

[0064] A multilayer electronic component 200 according to an embodiment of the present invention may include a body 110 , a first external electrode 231 and a second external electrode 232 .

[0065] The first external electrode 231 may include a first lower electrode layer 231a in contact with the first internal electrode 121 and arranged in the first connection portion P1a and the first band portion P1b, a first intermediate electrode layer 231b arranged on the first lower electrode layer 231a and extending from the first band portion P1b to a portion of the first connection portion P1a, and a first upper electrode layer 231c in contact with the first lower electrode layer 231a at the first connection portion P1a and in contact with the first intermediate electrode layer 231b in the first band portion P1b.

[0066] The second external electrode 232 may include a second lower electrode layer 232a in contact with the second internal electrode 122 and arranged in the second connection portion P2a and the second band portion P2b, a second intermediate electrode layer 232b arranged on the second lower electrode layer 232a and extending from the second band portion P2b to a portion of the second connection portion P2a, and a second upper electrode layer 232c in contact with the second lower electrode layer 232a at the second connection portion P2a and in contact with the second intermediate electrode layer 232b in the second band portion P2b.

[0067] The first external electrode 231 is disposed at the interface between the first lower electrode layer 231a and the first intermediate electrode layer 231b and may include a first alloy layer 231d including a Cu-Ag alloy. The second external electrode 232 is disposed at the interface between the second lower electrode layer 232a and the second intermediate electrode layer 232b and may include a second alloy layer 232d including a Cu-Ag alloy.

[0068] In the case of the multilayer electronic component 200 according to one embodiment of the present invention, one end of the intermediate electrode layers 231b, 232b may be disposed at the connection portions P1a, P2a. That is, one end of the first intermediate electrode layer 231b may be disposed at the first connection portion P1a, and one end of the second intermediate electrode layer 232b may be disposed at the second connection portion P2a. In addition, the first intermediate electrode layer 231b may be disposed so as to cover an end of the first lower electrode layer 231a in the first band portion P1b, and the second intermediate electrode layer 232b may be disposed so as to cover an end of the second lower electrode layer 232a in the second band portion P2b.

[0069] As a result, the alloy layers 231d, 232d cover parts of the lower electrode layers 231a, 232a at the connection portions P1a, P2a and cover the lower electrode layers 231a, 232a at the corner portions P1c, P2c, while covering the band portions P1b, P2b to the ends of the lower electrode layers 231a, 232a, thereby effectively improving the moisture resistance reliability of the laminated electronic component 200.

[0070] Furthermore, the lower electrode layers 231a, 232a and the upper electrode layers 231c, 232c are in contact with each other at the connection portions P1a, P2a, so that the electrical characteristics of the multilayer electronic component 200 can be improved.

[0071] The intermediate electrode layers 231b, 232b can be formed by dipping the main body 110, on which the lower electrode layers 231a, 232a are formed, into a conductive paste for the intermediate electrode layer, removing a portion of the conductive paste for the intermediate electrode layer that is applied to the central regions of the connection portions P1a, P2a from the conductive paste for the intermediate electrode layer that is applied to the connection portions P1a, P2a, and then firing the conductive paste for the intermediate electrode layer.

[0072] Fig. 7 is a cross-sectional view that illustrates a multilayer electronic component 300 according to another embodiment of the present invention, which is a modified example of Fig. 3. The multilayer electronic component 300 according to another embodiment of the present invention will be described below with reference to Fig. 7, but descriptions that overlap with those of the multilayer electronic component 100 according to the above-described embodiment of the present invention will be omitted.

[0073] A multilayer electronic component 300 according to an embodiment of the present invention may include a body 110 , a first external electrode 331 and a second external electrode 332 .

[0074] The first external electrode 331 may include a first lower electrode layer 331a in contact with the first internal electrode 121 and arranged in the first connection portion P1a and the first band portion P1b, a first intermediate electrode layer 331b arranged on the first lower electrode layer 331a and arranged in the first corner portion P1c and extending to each of portions of the first connection portion P1a and the first band portion P1b, and a first upper electrode layer 331c in contact with the first lower electrode layer 331a at the first connection portion P1a, in contact with the first intermediate electrode layer 331b at the first corner portion P1c, and in contact with the first lower electrode layer 331a in the first band portion P1b.

[0075] The second external electrode 332 may include a second lower electrode layer 332a in contact with the second internal electrode 122 and arranged in the second connection portion P2a and the second band portion P2b, a second intermediate electrode layer 332b arranged on the second lower electrode layer 332a, arranged in the second corner portion P2c and extending to each of portions of the second connection portion P2a and the second band portion P2b, and a second upper electrode layer 332c in contact with the second lower electrode layer 332a at the second connection portion P2a, in contact with the second intermediate electrode layer 332b at the second corner portion P2c, and in contact with the second lower electrode layer 332a in the second band portion P2b.

[0076] The first external electrode 331 is disposed at the interface between the first lower electrode layer 331a and the first intermediate electrode layer 331b and can include a first alloy layer 331d including a Cu-Ag alloy. The second external electrode 332 is disposed at the interface between the second lower electrode layer 332a and the second intermediate electrode layer 332b and can include a second alloy layer 332d including a Cu-Ag alloy.

[0077] In the case of the multilayer electronic component 300 according to one embodiment of the present invention, the alloy layers 331d, 332d cover the lower electrode layers 331a, 332a at the corner portions P1c, P2c, and cover the lower electrode layers 331a, 332a at the connection portions P1a, P2a and parts of the band portions P1b, P2b, thereby effectively improving the moisture resistance reliability of the multilayer electronic component 300.

[0078] Furthermore, not only do the lower electrode layers 331a, 332a and the upper electrode layers 331c, 332c contact each other at the connection portions P1a, P2a, but also the ends of the lower electrode layers 331a, 332a can contact the upper electrode layers 331c, 332c at the band portions P1b, P2b, thereby effectively improving the electrical characteristics of the multilayer electronic component 300.

[0079] The intermediate electrode layers 331b, 332b can be formed by applying a conductive paste for intermediate electrode layers to the corner portions P1c, P2c of the external electrodes 331, 332 after forming the lower electrode layers 331a, 332a, and then firing the paste.

[0080] The present invention is not limited by the above-described embodiments and the accompanying drawings, but is limited by the scope of the accompanying claims. Therefore, various substitutions, modifications and changes can be made by a person having ordinary knowledge in the art without departing from the technical idea of ​​the present invention described in the claims, and these also belong to the scope of the present invention.

[0081] In addition, the expression "one embodiment" does not mean the same embodiment, but is provided to emphasize and describe each unique feature that is different from the others. However, the above-mentioned one embodiment does not exclude being realized in combination with the features of another embodiment. For example, even if a matter described in a specific embodiment is not described in another embodiment, it can be understood as a description related to the other embodiment, unless there is a description that is opposite or contradictory to the matter in the other embodiment.

[0082] Furthermore, expressions such as "first, second" are used to distinguish one component from another, and do not limit the order and / or importance of the components. In some cases, the first component may be named the second component, and similarly the second component may be named the first component, within the scope of the rights. [Explanation of symbols]

[0083] 100, 200, 300: Multilayer electronic components 110: Main unit 111: Dielectric layer 112, 113: Cover part 114, 115: Margin 121, 122: Internal electrode 131, 132, 231, 232, 331, 332: External electrode 131a, 132a, 231a, 232a, 331a, 332a: lower electrode layer 131b, 132b, 231b, 232b, 331b, 332b: Intermediate electrode layer 131c, 132c, 231c, 232c, 331c, 332c: Upper electrode layer 131d, 132d, 231d, 232d, 331d, 332d: Alloy layer

Claims

1. a body including dielectric layers and internal electrodes alternately disposed with the dielectric layers, the body including first and second surfaces facing a first direction, third and fourth surfaces connected to the first and second surfaces and facing the second direction, and fifth and sixth surfaces connected to the first, second, third and fourth surfaces and facing the third direction; an external electrode including a connection portion disposed on the third surface and the fourth surface, and a band portion extending from the connection portion to a portion of the first surface and the second surface; The external electrode is a lower electrode layer in contact with the internal electrode and disposed at the connection portion and the band portion, an intermediate electrode layer disposed at the band portion and disposed on the lower electrode layer, and an upper electrode layer in contact with the lower electrode layer at the connection portion and in contact with the intermediate electrode layer at the band portion, the lower electrode layer includes Cu, and the intermediate electrode layer includes Ag; A multilayer electronic component, wherein an alloy layer containing a Cu--Ag alloy is disposed at the interface between the lower electrode layer and the intermediate electrode layer.

2. The multilayer electronic component according to claim 1 , wherein an average size of pores contained in the alloy layer is smaller than an average size of pores contained in the intermediate electrode layer.

3. 2. The multilayer electronic component according to claim 1, wherein in a cross section in the first and second directions passing through the center of the main body in the third direction, t1 is a thickness of a central region in the second direction of the intermediate electrode layer, and t2 is a thickness of a central region in the second direction of the alloy layer, and t1 > t2 is satisfied.

4. 2. The multilayer electronic component according to claim 1, wherein a molar ratio of Cu to Ag (Cu / Ag) is 5 or more and 60 or less in at least a portion of the alloy layer.

5. the lower electrode layer contains Cu as a main component, 2. The multilayer electronic component according to claim 1, wherein the intermediate electrode layer contains Ag as a main component.

6. 2. The multilayer electronic component according to claim 1, wherein the lower electrode layer and the intermediate electrode layer each include glass.

7. The multilayer electronic component according to claim 1 , wherein the upper electrode layer includes a Ni-plated layer and a Sn-plated layer disposed on the Ni-plated layer.

8. The multilayer electronic component according to claim 1 , wherein the intermediate electrode layer is disposed so as to cover an end portion of the lower electrode layer in the band portion.

9. the external electrode includes a corner portion disposed between the connection portion and the band portion, The multilayer electronic component according to claim 1 , wherein one end of the intermediate electrode layer is disposed at the corner portion.

10. The multilayer electronic component according to claim 1 , wherein the intermediate electrode layer is not disposed on the connection portion.

11. The multilayer electronic component according to claim 1 , wherein one end of the intermediate electrode layer is disposed on the connection portion.

12. the external electrode includes a corner portion disposed between the connection portion and the band portion, The multilayer electronic component according to claim 1 , wherein the intermediate electrode layer is disposed in the corner portion and extends over a portion of each of the connection portion and the band portion.

13. a body including dielectric layers and internal electrodes alternately disposed with the dielectric layers, the body including first and second surfaces facing a first direction, third and fourth surfaces connected to the first and second surfaces and facing the second direction, and fifth and sixth surfaces connected to the first, second, third and fourth surfaces and facing the third direction; an external electrode including a connection portion disposed on the third surface and the fourth surface, and a band portion extending from the connection portion to a portion of the first surface and the second surface; The external electrode is a lower electrode layer in contact with the internal electrode and disposed at the connection portion and the band portion, an intermediate electrode layer disposed at the band portion and disposed on the lower electrode layer, and an upper electrode layer in contact with the lower electrode layer at the connection portion and in contact with the intermediate electrode layer at the band portion, the lower electrode layer includes a first metal containing Cu as a main component; The intermediate electrode layer includes a second metal containing Ag as a main component.

14. an alloy layer including a Cu—Ag alloy is disposed at an interface between the lower electrode layer and the intermediate electrode layer; The multilayer electronic component according to claim 13 , wherein an average size of pores contained in the alloy layer is smaller than an average size of pores contained in the intermediate electrode layer.

15. 15. The multilayer electronic component according to claim 14, wherein, in a cross section in the first and second directions passing through the center of the main body in the third direction, t1 is a thickness of a central region in the second direction of the intermediate electrode layer, and t2 is a thickness of a central region in the second direction of the alloy layer, and t1 > t2 is satisfied.

16. 15. The multilayer electronic component according to claim 14, wherein a molar ratio of Cu to Ag (Cu / Ag) is 5 or more and 60 or less in at least a partial region of the alloy layer.

17. The laminated electronic component according to claim 13 , wherein the lower electrode layer and the intermediate electrode layer each include glass.

18. The multilayer electronic component according to claim 13 , wherein the upper electrode layer includes a Ni-plated layer and a Sn-plated layer disposed on the Ni-plated layer.

19. The multilayer electronic component according to claim 13 , wherein the intermediate electrode layer is disposed so as to cover an end portion of the lower electrode layer in the band portion.

20. the external electrode includes a corner portion disposed between the connection portion and the band portion, The multilayer electronic component according to claim 13 , wherein one end of the intermediate electrode layer is disposed at the corner portion.

21. The multilayer electronic component according to claim 13 , wherein the intermediate electrode layer is not disposed on the connection portion.

22. The multilayer electronic component according to claim 13 , wherein one end of the intermediate electrode layer is disposed in the connection portion.

23. the external electrode includes a corner portion disposed between the connection portion and the band portion, The multilayer electronic component according to claim 13 , wherein the intermediate electrode layer is disposed in the corner portion and extends over a portion of each of the connection portion and the band portion.

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