Multilayer electronic component

Abstract

A multilayer electronic component is provided. The multilayer electronic component can include a main body including a stack in which dielectric layers and internal electrodes are stacked in a first direction, and a cover portion provided on both surfaces of the stack opposite to each other in the first direction, and a corner of the cover portion has a rounded shape, and an external electrode. The external electrode can include a first electrode layer in contact with both surfaces of the stack opposite to each other in a second direction, and an end portion of the first electrode layer has a rounded shape, a second electrode layer provided on the first electrode layer, and a plating layer provided on the second electrode layer. T2 < R2 < 1.2 × T2 can be satisfied, where R2 is a radius of curvature of the end portion of the first electrode layer, and T2 is an average thickness of the first electrode layer in the second direction.

Description

[0001] This application claims the benefit of priority to Korean Patent Application No. 10-2025-0036122, filed on March 20, 2025, with the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference. Technical Field

[0002] This disclosure relates to a multilayer electronic component. Background Technology

[0003] Multilayer ceramic capacitors (MLCCs), as multilayer electronic components, are chip capacitors mounted on printed circuit boards of various electronic devices, including video display devices such as liquid crystal displays (LCDs) and plasma display panels (PDPs), computers, smartphones and mobile phones, and on-board chargers (OBCs) and DC-DC converters for electric vehicles, for charging or discharging.

[0004] When the thickness of the cover and edges is reduced to meet the miniaturization requirements of MLCCs, the brittleness of the main body may increase, thereby increasing the likelihood of chipping defects. Furthermore, as the outer electrode becomes thinner, breakage may occur at the corners of the outer electrode, or the density of the outer electrode may decrease, potentially reducing its ability to prevent the penetration of external moisture and plating solutions.

[0005] Conventional methods for addressing these issues include polishing the corners of the body to impart curvature. However, when the corners of the body are over-polished, the structural fragility of the corners may increase, and the risk of internal electrode exposure may also increase.

[0006] Therefore, structural improvements to the external electrode are needed to minimize the polishing of the corners of the main body while reducing edge chipping and breakage at the corners of the external electrode. Summary of the Invention

[0007] One aspect of this disclosure is to mitigate edge chipping defects that may occur as the curvature of the corners of the main body increases.

[0008] One aspect of this disclosure is to mitigate the problem that as the curvature of the corners of the main body increases, the thickness of the corners of the external electrodes may decrease or the corners of the external electrodes may break, thereby reducing the moisture resistance reliability of the multilayer electronic components.

[0009] However, the aspects of this disclosure are not limited to the foregoing and will be more readily understood in the process of describing specific exemplary embodiments of this disclosure.

[0010] A multilayer electronic component according to an example embodiment of this disclosure may include: a body comprising a stack and a cover, the stack including a dielectric layer and an inner electrode stacked in a first direction, the cover disposed on two surfaces of the stack opposite each other in the first direction, the corners of the cover having a rounded shape; and an outer electrode disposed on the body and connected to the inner electrode, the outer electrode comprising: a first electrode layer contacting two surfaces of the stack opposite each other in a second direction perpendicular to the first direction, the ends of the first electrode layer having a rounded shape; a second electrode layer disposed on the first electrode layer; and a plating layer disposed on the second electrode layer, wherein T2 is satisfied when the radius of curvature of the ends of the first electrode layer is defined as R2 and the average thickness of the first electrode layer in the second direction is defined as T2. <R2<1.2×T2。

[0011] One of the various effects of this disclosure is to reduce edge chipping defects in multilayer electronic components by making the corners of the cover and the ends of the electrode layer rounded, and by controlling the thickness of the cover and the radius of curvature of the corners of the cover.

[0012] One of the various effects of this disclosure is to reduce edge chipping defects in multilayer electronic components by giving the corners of the cover and the ends of the electrode layer rounded shapes and controlling the thickness of the electrode layer and the radius of curvature of the ends of the electrode layer.

[0013] One of the various effects of this disclosure is to mitigate edge chipping defects in multilayer electronic components by combining the rounded shape of the end of the electrode layer and the rounded shape of the corner of the cover portion as a single rounded shape.

[0014] One of the various effects of this disclosure is that by combining the rounded shape of the end of the electrode layer and the rounded shape of the corner of the cover to serve as a single rounded shape and enabling the corner of the outer electrode to form sufficient thickness, moisture resistance reliability is improved.

[0015] However, the aspects of this disclosure are not limited to the foregoing and can be more readily understood in the process of describing specific embodiments of this disclosure. Attached Figure Description

[0016] The above and other aspects, features and advantages of this disclosure will become clearer from the following detailed embodiments, taken in conjunction with the accompanying drawings, in which: Figure 1 This is a perspective view schematically illustrating a multilayer electronic assembly according to an exemplary embodiment of the present disclosure; Figure 2 It is along Figure 1 A schematic cross-sectional view of line I-I'; Figure 3 It is along Figure 1 A schematic cross-sectional view taken from line II-II'; Figure 4 This is an exploded perspective view schematically showing a main body having a stacked dielectric layer, inner electrodes, and a cover portion according to an example embodiment; Figure 5 yes Figure 2 A magnified view of region K; Figure 6 It shows the determination Figure 5 A schematic diagram of a method for determining the average thickness of the covering portion; and Figure 7 It shows the determination Figure 5 A schematic diagram of the method for averaging the thickness of the first electrode layer. Detailed Implementation

[0017] In the following description, exemplary embodiments of the present disclosure will be illustrated with reference to specific example embodiments and accompanying drawings. However, exemplary embodiments of the present disclosure may be exemplified in many different forms and should not be construed as limited to the specific embodiments set forth herein. Furthermore, the exemplary embodiments disclosed herein are provided to better explain the present disclosure to those skilled in the art. Therefore, in the drawings, the shape and size of elements may be exaggerated for clarity, and the same or similar reference numerals will always be used to denote the same or similar elements.

[0018] Furthermore, in the accompanying drawings, for the sake of clarity in describing this disclosure, details irrelevant to the description have been omitted, and the dimensions (e.g., thickness) of each component shown in the drawings are arbitrarily shown for ease of description, but this disclosure is not limited thereto. Additionally, the same reference numerals are used to describe components having the same function within the same conceptual scope. Throughout the specification, unless otherwise stated, when a part “comprises” or “includes” a component, this indicates that other components are not excluded and may be further included.

[0019] Figure 1 This is a perspective view schematically illustrating a multilayer electronic assembly according to an exemplary embodiment of the present disclosure.

[0020] Figure 2 It is along Figure 1 A schematic cross-sectional view taken from line I-I'.

[0021] Figure 3 It is along Figure 1 A schematic cross-sectional view taken from line II-II'.

[0022] Figure 4 This is an exploded perspective view schematically showing a body having a stacked dielectric layer, inner electrode, and cover according to an example embodiment.

[0023] Figure 5 yes Figure 2 A magnified view of region K.

[0024] Figure 6 It shows the determination Figure 5 A schematic diagram of a method for determining the average thickness of the covering portion.

[0025] Figure 7 It shows the determination Figure 5 A schematic diagram of the method for averaging the thickness of the first electrode layer.

[0026] Additionally, in the accompanying drawings, the x-direction (e.g., a first direction) may represent the thickness direction, the y-direction (e.g., a second direction) may represent the length direction, the z-direction (e.g., a third direction) may represent the width direction, and the stacking direction of the inner electrode or dielectric layer may be either the thickness direction or the width direction.

[0027] In the following text, reference will be made to Figures 1 to 7 A detailed description is provided of a multilayer electronic component 1000 according to exemplary embodiments of the present disclosure and various variant exemplary embodiments thereof.

[0028] A multilayer electronic component 1000 according to an exemplary embodiment of the present disclosure may include: a body 110 including a stack 100 and covers 112 and 113, wherein in the stack 100, dielectric layers 111 and inner electrodes 121 and 122 are stacked in a first direction, and covers 112 and 113 are disposed on two surfaces of the stack 100 opposite to each other in the first direction and have rounded corners CC; and outer electrodes 130 and 140 disposed on the body 110 and connected to the inner electrodes 121 and 122, wherein the outer electrodes 130 and 140 may include first electrode layers 131 and 141, a second electrode layer 121 and 122, a third electrode layer 121 and 122, a fourth electrode layer 121 and 122, a fifth electrode layer 121 and 122, a sixth electrode layer 121 and 122, a seventh electrode layer 121 and 122, a fifth electrode layer 121 and 122, a sixth electrode layer 121 and 122, a seventh electrode layer 121 and 122, a seventh electrode layer 121 and 122, a thief's ... Two electrode layers 132 and 142 and plating layers 133 and 143, first electrode layers 131 and 141 are in contact with two surfaces of the stack 100 that are opposite to each other in a second direction perpendicular to the first direction and have rounded ends EE, second electrode layers 132 and 142 are disposed on first electrode layers 131 and 141, plating layers 133 and 143 are disposed on second electrode layers 132 and 142, and when the radius of curvature of the ends EE of the first electrode layers 131 and 141 is defined as R2 and the average thickness of the first electrode layers 131 and 141 in the second direction is defined as T2, T2 can be satisfied. <R2<1.2×T2。

[0029] Although there are no specific restrictions on the exact shape of the main body 110, however... Figure 1 As shown, the body 110 may be formed in a hexahedral shape or a shape similar to a hexahedron. Due to the shrinkage of the ceramic particles included in the body 110 during the sintering process, the body 110 may not be a perfectly geometric hexahedral shape, but may have a generally hexahedral shape.

[0030] Reference Figure 1 , the main body 110 may include a first surface 1 and a second surface 2 opposite to each other 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 opposite to each other in a 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 opposite to each other in a third direction.

[0031] Reference Figure 2 and Figure 3 , the main body 110 may include a stacked body 100 in which internal electrodes 121, 122 and dielectric layers 111 are stacked in the first direction. The stacked body 100 may include a capacitance forming portion Ac and a region other than the capacitance forming portion Ac, wherein the capacitance forming portion Ac is a region where the first internal electrode 121 and the second internal electrode 122 overlap each other in the first direction.

[0032] The dielectric layers 111 forming the stacked body 100 are in a sintered state, and adjacent dielectric layers 111 may be integrated such that it is difficult to distinguish the boundaries therebetween without using a scanning electron microscope (SEM).

[0033] The raw material included in the dielectric layers 111 is not particularly limited as long as the material can achieve sufficient capacitance. For example, a barium titanate-based material, a lead composite perovskite-based material or a strontium titanate-based material may be used as the material. The barium titanate-based material may include BaTiO3-based ceramic particles. Examples of the BaTiO3-based ceramic particles may include BaTiO3 and (Ba 1-x Ca x )TiO3 (0<x<1), Ba(Ti 1-y Ca y )O3 (0<y<1), (Ba 1-x Ca x )(Ti 1-y Zr y )O3 (0<x<1, 0<y<1) or Ba(Ti 1-y Zr y )O3 (0<y<1).

[0034] Furthermore, for the purpose of the present disclosure, the raw material included in the dielectric layers 111 may be obtained by adding various ceramic additives such as organic solvents, binders, dispersants, etc. to particles such as barium titanate (BaTiO3).

[0035] The average thickness td of the dielectric layer 111 does not need to be particularly limited. For example, in order to easily achieve miniaturization and high capacitance of the multilayer electronic component 1000, the average thickness td of the dielectric layer 111 can be 0.35 μm or less. In order to improve the reliability of the multilayer electronic component 1000 under high temperature and high voltage, the average thickness td of the dielectric layer 111 can be 1 μm or greater.

[0036] The average thickness td of dielectric layer 111 may refer to the average thickness of at least one of the plurality of first dielectric layers in a first direction.

[0037] The average thickness of dielectric layer 111 in the first direction can be measured by scanning images of cross-sections of the multilayer electronic assembly 1000 in the first and second directions using a scanning electron microscope (SEM) at 10,000x magnification. More specifically, the average thickness of dielectric layer 111 in the first direction can refer to the average value calculated by measuring the thickness of one dielectric layer 111 in the first direction at four or more points spaced apart from each other in the second direction in the scanned image. The four or more equally spaced points can be specified in the capacitor forming section Ac. Furthermore, the average thickness of dielectric layer 111 in the first direction can be further generalized when the average thickness measurement is extended to four or more dielectric layers 111 to calculate the average value.

[0038] The inner electrodes 121 and 122 may be alternately disposed with the dielectric layer 111 in a first direction, and may include a first inner electrode 121 connected to the first outer electrode 130 and a second inner electrode 122 connected to the second outer electrode 140.

[0039] The first inner electrode 121 and the second inner electrode 122 can be electrically isolated from each other by a dielectric layer 111 between them.

[0040] There are no particular limitations on the materials included in the inner electrodes 121 and 122, and any material with excellent conductivity can be used. For example, the inner electrodes 121 and 122 may include one or more of nickel (Ni), copper (Cu), palladium (Pd), silver (Ag), gold (Au), platinum (Pt), tin (Sn), tungsten (W), titanium (Ti), and alloys thereof.

[0041] Furthermore, the internal electrodes 121 and 122 can be formed by printing a conductive paste for the internal electrodes onto a ceramic green sheet. The conductive paste for the internal electrodes includes one or more of nickel (Ni), copper (Cu), palladium (Pd), silver (Ag), gold (Au), platinum (Pt), tin (Sn), tungsten (W), titanium (Ti), and alloys thereof. The printing method for the conductive paste for the internal electrodes may include screen printing and gravure printing, and this disclosure is not limited thereto.

[0042] Furthermore, the thickness te of the inner electrodes 121 and 122 does not need to be particularly limited.

[0043] To facilitate miniaturization and high capacitance of the multilayer electronic component 1000, the average thickness te of the inner electrodes 121 and 122 can be 0.35 μm or less, and to improve the reliability of the multilayer electronic component 1000 under high temperature and high voltage, the average thickness te of the inner electrodes 121 and 122 can be 1 μm or greater.

[0044] The average thickness te of the inner electrodes 121 and 122 may refer to the average thickness of at least one of the inner electrodes 121 and 122 in the first direction.

[0045] The average thickness of the inner electrodes 121 and 122 in the first direction can be measured by scanning images of the cross-sections of the multilayer electronic assembly 1000 in the first and second directions using a scanning electron microscope (SEM) at 10,000x magnification. More specifically, the average thickness of an inner electrode in the first direction can be an average value obtained by measuring the thickness of an inner electrode in the first direction at four or more points spaced apart from each other in the second direction in the scanned image. The four or more equally spaced points can be specified in the capacitor forming section Ac. Furthermore, the average thickness of the inner electrodes 121 and 122 in the first direction can be further generalized when the average thickness measurement is calculated by extending it to four or more inner electrodes 121 and 122.

[0046] Reference Figure 2 and Figure 3 Covers 112 and 113 may be disposed on two surfaces of the stack 100 that are opposite to each other in a first direction. Covers 112 and 113 do not include the inner electrodes 121 and 122 and may include the same dielectric material as the dielectric material of the dielectric layer 111, but the specific composition of covers 112 and 113 may be different from that of the dielectric layer 111.

[0047] Furthermore, the average thickness T1 of the covers 112 and 113 does not need to be particularly limited. However, in order to easily achieve miniaturization and high capacitance of multilayer electronic components, the average thickness T1 of the covers 112 and 113 can be 15 μm or less. Here, the average thickness of the covers 112 and 113 may refer to the average thickness of each of the first cover 112 and the second cover 113.

[0048] The average thickness T1 of the covers 112 and 113 can represent the first directional dimension, and can be the average of the first directional dimensions of the covers 112 and 113 measured at five points spaced apart from each other at equal intervals on the upper or lower part of the stack 100.

[0049] Reference Figure 3Edge portions 114 and 115 may be disposed on two surfaces of the capacitor forming portion Ac in the third direction.

[0050] like Figure 3 As shown, the edges 114 and 115 may refer to the region between the two ends of the first inner electrode 121 and the second inner electrode 122 and the outer surface of the body 110 in a cross section obtained by cutting the body 110 along the width and thickness directions.

[0051] Edges 114 and 115 are essentially designed to prevent damage to the internal electrodes due to physical and / or chemical stress.

[0052] Edges 114 and 115 can be formed by applying conductive paste to the ceramic green sheet at locations other than where the edges will be formed to form internal electrodes.

[0053] In addition, in order to suppress the step difference caused by the inner electrodes 121 and 122, the inner electrodes can be stacked and then cut so that the inner electrodes are exposed on the two side surfaces of the capacitor forming portion Ac in the width direction. Then, a single dielectric layer or two or more dielectric layers can be stacked on the two side surfaces of the capacitor forming portion Ac in the width direction to form the edge portions 114 and 115.

[0054] Furthermore, the width wm of the edges 114 and 115 does not need to be specifically limited. However, in order to facilitate the miniaturization and high capacitance of multilayer electronic components, the average width of the edges 114 and 115 can be 15 μm or less.

[0055] The average width wm of the edges 114 and 115 can refer to the average dimension of the edges 114 and 115 in the third direction, and can be obtained by averaging the third-direction dimensions of the edges 114 and 115 measured at five points spaced apart from each other at equal intervals on the side surface of the capacitor forming part Ac.

[0056] External electrodes 130 and 140 are disposed on the main body 110.

[0057] External electrodes 130 and 140 are disposed on the third surface 3 and the fourth surface 4, which are surfaces of the body 110 facing each other in a second direction perpendicular to the first direction. The external electrodes 130 and 140 are connectable to the internal electrodes 121 and 122. Specifically, the first external electrode 130 may be disposed on the third surface 3 and connected to the first internal electrode 121. The third surface 3 is a surface of the body 110 oriented in a second direction perpendicular to the first direction. The second external electrode 140 may be disposed on the fourth surface 4 and connected to the second internal electrode 122. The fourth surface 4 is another surface of the body 110 oriented in a second direction perpendicular to the first direction.

[0058] Although this example embodiment describes a multilayer electronic assembly 1000 having a structure with two external electrodes 130 and 140, the number and shape of the external electrodes 130 and 140 may vary depending on the shape of the internal electrodes 121 and 122 or for other purposes.

[0059] Reference Figure 2 The external electrodes 130 and 140 may include: first electrode layers 131 and 141, which are in contact with two surfaces of the stack 100 that are opposite to each other in a second direction perpendicular to the first direction, and the ends of the first electrode layers 131 and 141 have rounded shapes; second electrode layers 132 and 142, which are disposed on the first electrode layers 131 and 141; and plating layers 133 and 143, which are disposed on the second electrode layers 132 and 142. Furthermore, the first electrode layers 131 and 141 may also be in contact with a portion of the two surfaces of each of the covers 112 and 113 that are opposite to each other in the second direction.

[0060] The first electrode layers 131 and 141 are electrode layers that directly contact the stack 100 and can be used to ensure electrical connectivity with the inner electrodes 121 and 122. Therefore, the first electrode layers 131 and 141 can directly contact the second-direction ends of at least some of the plurality of inner electrodes 121 and 122.

[0061] The first electrode layers 131 and 141 may be one of the following: a sintered electrode comprising a conductive metal and glass; a plating layer comprising a conductive metal; a conductive resin layer comprising a conductive metal and resin; a heavily (highly) doped semiconductor layer comprising high concentrations of impurities; and a conductive polymer layer comprising a conductive metal and a conductive polymer.

[0062] In the example embodiment, when the first electrode layers 131 and 141 include a conductive metal, the conductive metal may refer to a single-atom metal such as Cu, Ni, Ag, Au, Pd or Pt, or an alloy including two or more elements selected from Cu, Ni, Ag, Au, Pd and Pt.

[0063] In an example embodiment, when the first electrode layers 131 and 141 comprise a conductive polymer, the conductive polymer may be one or more of polyacetylene (PA), polypyrrole (PPy), polyaniline (PANI), poly(3,4-ethylenedioxythiophene) (PEDOT), and polythiophene (PT).

[0064] There are no particular limitations on the method for forming the first electrode layers 131 and 141. However, plating methods such as electroplating and electroless plating, or deposition methods such as chemical vapor deposition (CVD) and physical vapor deposition (PVD), can be used to form thin and dense electrode layers, and the first electrode layers 131 and 141 can also be formed by coating a paste comprising a conductive metal and a resin or conductive polymer, or by coating a paste comprising a conductive metal and glass.

[0065] Furthermore, when forming the first electrode layers 131 and 141 using a plating method, Ni can be plated from the ends of the inner electrodes 121 and 122, which is beneficial for the growth of the plating. That is, in the example embodiment, the first electrode layers 131 and 141 may include Ni, and the Ni content may be 90 at% or more, or 60 at% or more, relative to the total content of all elements except oxygen included in the first electrode layers 131 and 141. The Ni content can be determined by energy-dispersive X-ray spectroscopy (EDX). Other methods and / or tools understood by those skilled in the art may be used even if not described in this disclosure.

[0066] The second electrode layers 132 and 142 may be disposed on the first electrode layers 131 and 141. The composition of the second electrode layers 132 and 142 is not particularly limited, as long as the second electrode layers 132 and 142 cover the first electrode layers 131 and 141 and ensure the conductivity of the outer electrodes 130 and 140.

[0067] However, in the example embodiment, the second electrode layers 132 and 142 may include conductive metal and glass, thereby ensuring adhesion between the outer electrodes 130 and 140 and the body 110.

[0068] In an example embodiment, second electrode layers 132 and 142 may be disposed on first electrode layers 131 and 141, and may be configured to cover the corners CC of covers 112 and 113. Therefore, the adhesion between the outer electrodes 130 and 140 and the body 110 can be further enhanced, and the moisture resistance reliability of the multilayer electronic assembly 1000 can be further improved.

[0069] Platings 133 and 143 can be used to improve the sealing performance or mounting characteristics of the multilayer electronic assembly 1000. There are no particular limitations on the type of platings 133 and 143, and they can be one or more of Ni, Sn, Pd and their alloys, and can consist of multiple layers.

[0070] For a more specific example of plating layers 133 and 143, plating layers 133 and 143 may comprise a Ni plating layer comprising Ni or a Sn plating layer comprising Sn, or may have a Ni plating layer and a Sn plating layer sequentially formed on the second electrode layers 132 and 142, or may have a Sn plating layer, a Ni plating layer, and a Sn plating layer sequentially formed. Furthermore, plating layers 133 and 143 may comprise multiple Ni plating layers and / or multiple Sn plating layers.

[0071] When the cover and edges are made thinner to miniaturize multilayer electronic components, the fragility of the body may increase, leading to damage to the external and internal microstructures of the multilayer electronic components.

[0072] One example of a conventional approach to addressing these issues is polishing the corners of the body to impart curvature. However, over-polishing the corners can increase their structural fragility and potentially increase the risk of internal electrode exposure. Furthermore, as the curvature of the corners increases (radius of curvature decreases), the external electrodes 130 and 140 disposed on the body may become thinner or even break at the corners.

[0073] On the other hand, in the exemplary embodiments of this disclosure, the corners CC of the covers 112 and 113 and the ends EE of the first electrode layers 131 and 141 are all formed with a rounded shape, and the correlation between two or more of the following can be controlled: the average thickness T1 of the covers, the radius of curvature R1 of the corners CC of the covers 112 and 113, the average thickness T2 of the first electrode layers 131 and 141, the radius of curvature R2 of the ends EE of the first electrode layers 131 and 141, and the distance D in the first direction from the outermost point P3 of the ends EE of the first electrode layers 131 and 141 in the first direction to the outermost point P1 of the corners CC of the covers 112 and 113 in the first direction. This can reduce the risk of increased structural fragility of the corners CC of the covers 112 and 113 in the corners of the body 110, which can mitigate the problem of forming excessive curvature (reduced radius of curvature) at the corners CC to form the outer electrodes 130 and 140 locally thinner or to disconnect the outer electrodes 130 and 140. For example, the first directional distance D can be the distance between the second directional extension line E1 of the outermost point P3 of the ends EE of the first electrode layers 131 and 141 in the first direction and the second directional extension line E2 of the second surface 2.

[0074] In the following text, refer to Figure 5The correlation between two or more of the following will be described in detail: the average thickness T1 of the cover portion, the radius of curvature R1 of the corner CC of the covers portions 112 and 113, the average thickness T2 of the first electrode layers 131 and 141, the radius of curvature R2 of the ends EE of the first electrode layers 131 and 141, and the distance D in the first direction from the outermost point P3 of the ends EE of the first electrode layers 131 and 141 in the first direction to the outermost point P1 of the corner CC of the covers portions 112 and 113 in the first direction. Hereinafter, the first electrode layer 131 based on the first outer electrode 130 and the first cover portion 112 disposed on the upper surface of the stack 100 will be described. However, the features described below can also be applied between the first electrode layer 141 and the first cover portion 112, between the first electrode layer 131 and the second cover portion 113, and between the first electrode layer 141 and the second cover portion 113.

[0075] Reference Figure 5 The first electrode layer 131 may have an end EE, and the end EE may refer to the first direction end (first direction end surface) of the first electrode layer 131 having a rounded shape. Furthermore, in Figure 5 In this context, the radius of curvature of the end EE of the first electrode layer 131 is denoted as R2. Furthermore, reference is also made to... Figure 5 The cover portion 112 may have a corner CC, and the corner CC may refer to the corner that connects the second surface 2 and the third surface 3 of the body 110. After the first electrode layer 131 is formed on the stack 100, the end portion EE of the first electrode layer 131 and the corner CC of the cover portion 112 can be formed into a rounded shape by performing a separate polishing process.

[0076] There are no particular restrictions on the type of polishing process used for the end EE of the first electrode layer 131 and the corner CC of the cover portion 112, but a rounded shape can be formed at the end EE of the first electrode layer 131 and the corner CC of the cover portion 112 by dry polishing or wet polishing.

[0077] Furthermore, R1 and R2 can be different, and there are no particular limitations on the methods used to form different R1 and R2. Preferably, the end EE of the first electrode layer 131 and the corner CC of the cover portion 112 can exhibit differences in hardness depending on their materials. Therefore, even under the same external force, different radii of curvature can be formed. In addition, in the case of the cover portion 112, since the cover portion 112 undergoes polishing in the green sheet state before sintering, and may undergo further polishing after the formation of the first electrode layer 131 after sintering, the values ​​of R1 and R2 can differ.

[0078] In an exemplary embodiment of the present disclosure, since each of the corners CC of the covering portions 112 and 113 and the end portions EE of the first electrode layers 131 and 141 has a rounded shape, the rounded shape of the corners CC of the covering portions 112 and 113 and the rounded shape of the end portions EE of the first electrode layers 131 and 141 can be combined to form a new virtual rounded shape. Due to the combination of R1 and R2, the radius of curvature of the new virtual rounded shape (i.e., the radius of the virtual circle) R3 can have a larger value than the values of R1 and R2. This can alleviate the problem of chipping defects in the multilayer electronic component 1000 and the problem of local reduction or disconnection of the thickness of the external electrodes 130 and 140 caused by large curvature (small radius of curvature) at the corners of the main body 110.

[0079] Furthermore, in the exemplary embodiment of the present disclosure, the radius of curvature R2 of the end portions EE of the first electrode layers 131 and 141 and the average thickness T2 of the first electrode layers 131 and 141 in the second direction can satisfy T2 < R2 < 1.2×T2. If R2 is less than or equal to T2, it may be difficult to achieve a sufficient radius of curvature enhancement effect. If R2 is greater than or equal to 1.2×T2, the first-direction distance D between the outermost point P3 in the first direction of the end portions EE of the first electrode layers 131 and 141 and the outermost point P1 in the first direction of the corners CC of the covering portions 112 and 113 may increase excessively, thereby reducing the effect of the present disclosure brought by the combination of the rounded shape of the corners CC of the covering portions 112 and 113 and the rounded shape of the end portions EE of the first electrode layers 131 and 141 to form a new virtual rounded shape.

[0080] In an exemplary embodiment, the radius of curvature R1 of the corners CC of the covering portions 112 and 113 and the average thickness T1 of the covering portions 112 and 113 in the first direction can satisfy 0.3×T1 < R1 < 0.5×T1. When R1 is less than or equal to 0.3×T1, the covering portions 112 and 113 may form excessively large curvature, thereby increasing the fragility of the corners CC, and the distance between the outermost point P3 in the first direction of the end portions EE of the first electrode layers 131 and 141 and the outermost point P2 in the second direction of the corners CC of the covering portions 112 and 113 may increase, thereby reducing the effect of the present disclosure brought by the new radius of curvature R3 formed by the combination of R1 and R2. When R1 is greater than or equal to 0.5×T1, the radius of curvature may be relatively large, thereby reducing the effect of the present disclosure brought by the combination of the rounded shape of the corners CC of the covering portions 112 and 113 and the rounded shape of the end portions EE of the first electrode layers 131 and 141 to form a new virtual rounded shape.

[0081] In an example embodiment, the radius of curvature R2 of the end portions EE of the first electrode layers 131 and 141, the radius of curvature R1 of the corners CC of the covering portions 112 and 113, and the average thickness T1 of the covering portions 112 and 113 in the first direction may satisfy 0.6×T1 < R1+R2 < 1.1×T1. When R1+R2 is less than or equal to 0.6×T1, the effect of suppressing chipping defects in the multilayer electronic component 1000 may be reduced. When R1+R2 is greater than or equal to 1.1×T1, the rounded shape of the corners CC of the covering portions 112 and 113 and the rounded shape of the end portions EE of the first electrode layers 131 and 141 may each function as an overall rounded shape, and a new virtual rounded shape cannot be formed by combining the rounded shape of the corners CC of the covering portions 112 and 113 and the rounded shape of the end portions EE of the first electrode layers 131 and 141. Specifically, if the distance between the rounded shape of the end portion EE and the rounded shape of the corner CC is excessively large, or the total size of these two rounded shapes exceeds a certain level, it may be difficult for these two rounded shapes to jointly act as a new virtual rounded shape. In the present invention, forming a new virtual rounded shape means that the rounded shape of the corner CC of the covering portion and the rounded shape of the end portion EE of the first electrode layer jointly serve as a substantially continuous curved surface, thereby reducing stress concentration. Therefore, if R1 or R1+R2 becomes excessively large (for example, if R1+R2 is greater than or equal to 1.1×T1), these two rounded shapes may function independently instead of synergistically, and the above effect may be weakened. In contrast, within the range where these two rounded shapes are combined to form a virtual rounded shape, chipping defects near the corners of the covering portion can be suppressed more effectively.

[0082] In an example embodiment, the average thickness T2 of the first electrode layers 131 and 141 in the second direction may satisfy 2 μm ≤ T2 ≤ 5 μm. If T2 is less than 2 μm, the effect of suppressing chipping defects in the multilayer electronic component 1000 and the effect of suppressing disconnection of the external electrodes 130 and 140 may be reduced. If T2 exceeds 5 μm, the external electrodes 130 and 140 occupy an excessively large proportion of the entire multilayer electronic component 1000, and therefore the capacitance per unit volume of the multilayer electronic component 1000 may decrease.

[0083] In an example embodiment, the radius of curvature R1 of the corner of the covering portion, the average thickness T1 of the covering portion in the first direction, and the average thickness T2 of the first electrode layers 131 and 141 in the second direction may satisfy R1 ≤ T1 / 2 and T2 ≤ T1 / 2. If R1 exceeds T1 / 2 or T2 exceeds T1 / 2, the effect of suppressing chipping defects according to the present disclosure may be reduced.

[0084] In an example embodiment, a curvature radius R1 of a corner of a covering portion and a first-direction distance D between an outermost point P3, in a first direction, of an end of a first electrode layer and an outermost point P1, in the first direction, of the corner of the covering portion may satisfy R1≤D≤1.5×R1. If D is less than R1 or exceeds 1.5×R1, the rounded shape of the corners CC of the covering portions 112 and 113 and the rounded shape of the ends EE of the first electrode layers 131 and 141 may be too close or not close enough, resulting in a reduction in the effect of the present disclosure brought about by combining the rounded shapes to form a new virtual rounded shape. In addition, D may be the distance in the first direction from the point P3, which is the point on the end of the first electrode layer closest to the outermost point P1, in the first direction, of the corner of the covering portion, to the outermost point P1, in the first direction, of the corner of the covering portion.

[0085] In an example embodiment, the combination of the rounded shape of the corners CC of the covering portions 112 and 113 and the rounded shape of the ends EE of the first electrode layers 131 and 141 to form a new virtual rounded shape may mean that when a radius of a virtual circle passing through an outermost point P4, in a second direction, of the ends EE of the first electrode layers 131 and 141 and the outermost point P1, in the first direction, of the corners CC of the covering portions 112 and 113 is defined as R3, R1<R3 and R2<R3 are satisfied. In addition, the virtual circle may pass through the point P4, which is the farthest point on the end of the first electrode layer from the outermost point P1, in the first direction, of the corner of the covering portion. For example, among all circles passing through the point P1 and the point P4, the circle with the smallest radius (that is, the circle where the point P1 and the point P4 are respectively located at two ends of a diameter) is selected as the virtual circle.

[0086] In an example embodiment, the first electrode layers 131 and 141 may be in contact with a stacked body 100, but may not be disposed on a first surface 1 and a second surface 2 of a main body 110, and may be disposed so as not to extend beyond the corners CC of the covering portions 112 and 113. When the first electrode layers 131 and 141 are disposed on the corners CC of the covering portions 112 and 113 or disposed to extend beyond the corners CC of the covering portions 112 and 113 and disposed on the first surface 1 and the second surface 2 of the main body 110, the effect of the present disclosure of mitigating chipping defects in a multilayer electronic component 1000 may be slightly insufficient.

[0087] Furthermore, in the example embodiment, the fact that the first electrode layers 131 and 141 are configured not to extend beyond the corner CC of the covers 112 and 113 means that the ends EE of the first electrode layers 131 and 141 are spaced apart from the corner CC of the covers 112 and 113. More specifically, the fact that the first electrode layers 131 and 141 are configured not to extend beyond the corner CC of the covers 112 and 113 means that the outermost point P3 of the ends EE of the first electrode layers 131 and 141 in the first direction is spaced apart from the outermost point P2 of the corner CC of the covers 112 and 113 in the second direction.

[0088] Furthermore, according to an example embodiment, R1, R2, R3, D, T1, and T2 can be measured by observing a first and second direction cross-section of the polished multilayer electronic assembly 1000 to a third upward 1 / 2 point using optical equipment such as an optical microscope (OM) or a scanning electron microscope (SEM). Other methods and / or tools understood by those skilled in the art may be used, even if not described in this disclosure. In this application, R1 and R2 can be measured in a locally magnified region of a corner of the body 110 or the covers 112 and 113, and preferably, a corner of the body 110 or the covers 112 and 113 and the region of the first direction ends of the first electrode layers 131 and 141 can be observed simultaneously.

[0089] Furthermore, the average thickness T1 of the covers 112 and 113 can refer to the average thickness of the covers 112 and 113 in the first direction. The average thickness of the covers 112 and 113 in the first direction can be measured by using a scanning electron microscope (SEM) to scan cross-sections of the body 110 in the first and second directions at 10,000x magnification. More specifically, as... Figure 6 As shown, the average thickness T1 of the covers 112 and 113 can be an average value calculated by measuring the thickness of the cover 112 in the first direction at five or more points (Q1, Q2, Q3, Q4, Q5, etc.) that are equally spaced apart from each other in the second direction in an image obtained by scanning one cover 112. Q0 and Q6 can represent the extensions of the third and fourth surfaces of the body 110, respectively, and the points Q1, Q2, Q3, Q4, Q5 are equally spaced between the extensions Q0 and Q6.

[0090] Furthermore, the average thickness T2 of the first electrode layers 131 and 141 can refer to the average thickness of the first electrode layers 131 and 141 in the second direction. The average thickness of the first electrode layers 131 and 141 can be measured by using a scanning electron microscope (SEM) to scan cross-sections of the multilayer electronic assembly 1000 in the first and second directions at 10,000x magnification. More specifically, as Figure 7As shown, the average thickness T2 of the first electrode layers 131 and 141 can be: an average value calculated by measuring the thickness of a first electrode layer 131 or 141 in a second direction at five or more points (S1, S2, S3, S4, S5, etc.) that are equally spaced apart in the first direction in an image obtained by scanning a first electrode layer 131 or 141, in the region between a straight line R6 extending from the uppermost point of the first inner electrode 121 located at the uppermost end in the first direction and a straight line R0 extending from the lowermost point of the first inner electrode 121 located at the lowermost end in the first direction. For example, the five or more points (S1, S2, S3, S4, S5, etc.) can be located on the extension line EO of the outer surface of the first electrode layers 131 and 141 in the second direction.

[0091] (Example) Table 1 below measures and evaluates the chipping defect rate, outer electrode corner thickness, and moisture resistance reliability of multilayer electronic component samples based on variations in T1, T2, R1, R2, R3, and D. For each test number, the dielectric layer, inner electrode, cover, and edge are formed using the same materials. Ni plating is performed on the stack to form the first electrode layer, and a conductive paste including Cu and glass is applied to form the second electrode layer, followed by Ni and Sn plating. To vary T1, T2, R1, R2, R3, and D for each test number, dry polishing is performed on the corners of the cover and the ends of the first electrode layer before forming the second electrode layer, and separate dry polishing is performed in the green wafer state before forming the first electrode layer.

[0092] The chipping defect rate is determined by the number of defective samples with chipping observed in the cover and edge of 2000 samples for each test number.

[0093] The thickness of the corner of the outer electrode was measured in the thinnest portion of the corner region of the outer electrode in the first direction (x-direction) and the second direction (y-direction) section at the half point of the third direction in the polished multilayer electronic component. The thickness of the corner of the outer electrode was obtained by measuring a total of 20 thickness values ​​for both the first and second outer electrodes of 10 multilayer electronic component samples for each test number and calculating their average value.

[0094] Moisture resistance reliability was evaluated for 400 samples at each test number under the following conditions, and when one or more of the 400 samples at a given test number showed a value of 10... 5 When the insulation resistance value is Ω or smaller, the test result for this test number is evaluated as NG; otherwise, it is evaluated as OK.

[0095] (Moisture resistance reliability evaluation conditions): Temperature: 85℃, relative humidity: 85%, applied voltage: 1Vr, and voltage application time: 3 hours. Table 1:

[0096] It is confirmed that in test number 1 where the first electrode layer was not formed, the edge chipping defect rate was 45,000 ppm, but in test number 2 where the first electrode layer was formed, the edge chipping defect rate decreased to 43,000 ppm. In other words, as in the exemplary embodiment of this disclosure, when each of the ends EE of the first electrode layers 131 and 141 and the corners CC of the covers 112 and 113 has a rounded shape, it can be seen that the problem of edge chipping defects occurring in the multilayer electronic assembly 1000 can be mitigated due to the radius R3 of the virtual circle formed.

[0097] Furthermore, for test numbers 4, 5, 7, and 8 according to the example embodiment where the condition R1≤D≤1.5×R1 is not met, it can be confirmed that when the value of D is less than R1 or greater than 1.5×R1, although the radius R3 of the virtual circle is greater than R1 and R2, the effect of improving edge chipping defects is slightly insufficient, and the moisture resistance reliability can also be confirmed as NG. On the other hand, for test numbers 3 and 6 according to the example embodiment where the condition R1≤D≤1.5×R1 is met, it can be confirmed that the effect of improving edge chipping defects is excellent, and the moisture resistance reliability is also OK. Therefore, when R1≤D≤1.5×R1 is met as in the example embodiment, the effect of improving edge chipping defects and the effect of improving moisture resistance reliability according to this disclosure can be significantly improved.

[0098] Although exemplary embodiments of the present disclosure have been described in detail above, the present disclosure is not limited to the above embodiments and drawings, but is defined by the appended claims. Therefore, various substitutions, modifications, or changes can be made by those skilled in the art without departing from the scope of the present disclosure as defined by the appended claims, and such substitutions, modifications, or changes should be construed as being included within the scope of the present disclosure.

[0099] Furthermore, the expression "example embodiment" as used in this disclosure does not imply the same embodiment and is provided to emphasize and explain different unique features. However, the example embodiments presented above do not preclude implementation in combination with features of another embodiment. For example, although what is described in a particular embodiment is not described in another embodiment, such content may be understood as a description relating to another embodiment, unless there is a description in another embodiment that contradicts or contradicts such content.

[0100] In this disclosure, terminology is used only to describe particular embodiments and is not intended to limit the scope of the disclosure. Unless the context clearly indicates otherwise, the singular form may also include the plural form.

Claims

1. A multilayer electronic component, comprising: a main body including a stacked body and covering portions, wherein the stacked body includes dielectric layers and internal electrodes stacked in a first direction, the covering portions are provided on two surfaces of the stacked body opposite to each other in the first direction, and corners of the covering portions have a rounded shape; and an external electrode provided on the main body and connected to the internal electrodes, wherein the external electrode comprises: a first electrode layer in contact with two surfaces of the stacked body opposite to each other in a second direction perpendicular to the first direction, wherein an end portion of the first electrode layer has a rounded shape; a second electrode layer provided on the first electrode layer; and a plating layer provided on the second electrode layer, wherein when a radius of curvature of the end portion of the first electrode layer is defined as R2 and an average thickness of the first electrode layer in the second direction is defined as T2, a relationship of T2 < R2 < 1.2×T2 is satisfied.

2. The multilayer electronic component according to claim 1, wherein, when a radius of curvature of the corner of the covering portion is defined as R1 and an average thickness of the covering portion in the first direction is defined as T1, a relationship of 0.3×T1 < R1 < 0.5×T1 is satisfied.

3. The multilayer electronic component according to claim 1, wherein, when a radius of curvature of the corner of the covering portion is defined as R1 and an average thickness of the covering portion in the first direction is defined as T1, a relationship of 0.6×T1 < R1+R2 < 1.1×T1 is satisfied.

4. The multilayer electronic component according to claim 1, wherein, a relationship of 2μm ≤ T2 ≤ 5μm is satisfied.

5. The multilayer electronic component according to claim 1, wherein, when a radius of curvature of the corner of the covering portion is defined as R1 and an average thickness of the covering portion in the first direction is defined as T1, relationships of R1 ≤ T1 / 2 and T2 ≤ T1 / 2 are satisfied.

6. The multilayer electronic assembly according to claim 1, wherein, when a radius of curvature of the corner of the covering portion is defined as R1 and a distance from an outermost point, in the first direction, of the end portion of the first electrode layer to an outermost point, in the first direction, of the corner of the covering portion in the first direction is defined as D, a relationship of R1 ≤ D ≤ 1.5×R1 is satisfied.

7. The multilayer electronic assembly according to claim 1, wherein, the end portion of the first electrode layer is spaced apart from the corner of the covering portion.

8. The multilayer electronic component according to claim 1, wherein, the first electrode layer includes a conductive metal and a conductive polymer.

9. The multilayer electronic component according to claim 1, wherein, the first electrode layer includes Ni, and a content of Ni is 90at% or more relative to a total content of elements other than oxygen included in the first electrode layer.

10. The multilayer electronic assembly according to claim 1, wherein, the second electrode layer includes a conductive metal and glass.

11. The multilayer electronic assembly according to claim 10, wherein, the second electrode layer covers the corner of the covering portion.

12. The multilayer electronic assembly according to claim 1, wherein, when a radius of curvature of the corner of the covering portion is defined as R1 and a radius of an imaginary circle passing through an outermost point, in the second direction, of the end portion of the first electrode layer and an outermost point, in the first direction, of the corner of the covering portion is defined as R3, relationships of R1 < R3 and R2 < R3 are satisfied.

13. The multilayer electronic component according to claim 6, wherein, the outermost point, in the first direction, of the end portion of the first electrode layer is a point on the end portion of the first electrode layer that is closest to the outermost point, in the first direction, of the corner of the covering portion.

14. The multilayer electronic assembly according to claim 12, wherein, The outermost point of the end of the first electrode layer in the second direction is the point on the end of the first electrode layer that is farthest from the outermost point of the corner of the covering portion in the first direction.

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