Capacitor components

Abstract

The present invention provides a capacitor component, which includes: a main body, the main body includes a stacking portion in which a first inner electrode and a second inner electrode opposite to each other are stacked in a first direction, and a first connecting portion and a second connecting portion, the first connecting portion and the second connecting portion are respectively arranged on two surfaces of the stacking portion in a second direction perpendicular to the first direction and are respectively connected to the first inner electrode and the second inner electrode; and a first external electrode and a second external electrode, the first external electrode and the second external electrode are respectively arranged on the first connecting portion and the second connecting portion, and the first external electrode and the second external electrode include metal particles, and the surface of each of the metal particles is coated with at least one of graphene and carbon nanotubes.

Description

[0001] This application is a divisional application of the invention patent application with application date of January 16, 2020, application number 202010045026.3, and titled “Capacitor Assembly”. Technical Field

[0002] The present disclosure relates to a capacitor assembly. Background Art

[0003] A multilayer ceramic capacitor (MLCC), a capacitor component, has a small size and high capacitance, and can be easily mounted.

[0004] Generally, when forming external electrodes in an MLCC, a paste including a conductive metal may be used, and a surface of a body on which the internal electrodes are exposed may be immersed in the paste.

[0005] However, the thickness of the external electrodes formed by the dipping method may be uneven, and the thickness of the external electrodes at the corners of the body may be excessively reduced. In addition, when forming a plating layer on the external electrodes, the plating solution may penetrate into the body, which may reduce the reliability of the MLCC.

[0006] In order to solve the above problems, the external electrode may be divided into a primary external electrode and a secondary external electrode, and the primary external electrode may be formed by a transfer process (or transfer printing), etc. However, when the above method is used, the contact area between the internal electrode and the external electrode may be reduced compared to the use of the ordinary method, and thus, the resistance and ESR may be increased. Summary of the invention

[0007] An aspect of the present disclosure is to provide a capacitor assembly having improved moisture resistance reliability and having reduced ESR by improving electrical conductivity.

[0008] According to one aspect of the present disclosure, there is provided a capacitor component, the capacitor component comprising: a main body, the main body comprising a stacked portion in which first and second internal electrodes facing each other are stacked in a first direction, and a first connecting portion and a second connecting portion, the first connecting portion and the second connecting portion are respectively arranged on two surfaces of the stacked portion in a second direction perpendicular to the first direction and are respectively connected to the first and second internal electrodes; and a first external electrode and a second external electrode, the first external electrode and the second external electrode are respectively arranged on the first connecting portion and the second connecting portion. The first external electrode and the second external electrode include metal particles, and the surface of each of the metal particles is coated with at least one of graphene and carbon nanotubes.

[0009] A capacitor assembly comprises: a main body, the main body comprising a stacking portion and a first connecting portion and a second connecting portion, the stacking portion comprising a first inner electrode and a second inner electrode opposite to each other and stacked in a first direction, and a dielectric layer interposed between the first inner electrode and the second inner electrode, the first connecting portion and the second connecting portion are respectively arranged on opposite surfaces of the stacking portion in a second direction perpendicular to the first direction and are respectively connected to the first inner electrode and the second inner electrode; and a first outer electrode and a second outer electrode, respectively arranged on the first connecting portion and the second connecting portion, wherein the first connecting portion and the second connecting portion respectively comprise a metal layer arranged on the stacking portion and a ceramic layer arranged on the metal layer.

[0010] According to one aspect of the present disclosure, there is provided a method for manufacturing a capacitor assembly, the method comprising: forming a body by transferring a first connection portion and a second connection portion in a second direction perpendicular to a first direction to connect to a first inner electrode and a second inner electrode of a laminated portion, in which a dielectric layer is laminated with the first inner electrode and the second inner electrode in the first direction; and forming a first outer electrode and a second outer electrode on the first connection portion and the second connection portion, respectively. The first outer electrode and the second outer electrode include metal particles, and a surface of each of the metal particles is coated with at least one of graphene and carbon nanotubes. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The above and other aspects, features and advantages of the present disclosure will be more clearly understood through the following detailed description in conjunction with the accompanying drawings, in which:

[0012] Figure 1 is a perspective view showing a capacitor assembly according to an example embodiment of the present disclosure;

[0013] Figure 2 It is shown Figure 1 A perspective view of the subject shown in FIG.

[0014] Figure 3 It is shown Figure 1 A perspective view of a laminated portion shown in FIG.

[0015] Figure 4 It is along Figure 1 A cross-sectional view taken along line II' in FIG.

[0016] Figure 5A and Figure 5B is Figure 1 The cross-sectional views taken in the X direction and the Y direction are shown in FIG. Figure 5A is a cross-sectional view showing a first inner electrode, Figure 5B is a cross-sectional view showing a second inner electrode;

[0017] Figure 6 is a diagram illustrating a metal particle according to an example embodiment of the present disclosure, the surface of the metal particle being coated with graphene;

[0018] Figure 7 is a diagram showing an external electrode including metal particles, a surface of each of which is coated with graphene, according to an example embodiment of the present disclosure;

[0019] Figures 8 to 11 is a diagram illustrating a process for forming a connection portion of a capacitor assembly using a transfer method according to an example embodiment of the present disclosure; and

[0020] Fig.12 is a diagram illustrating a process for forming an external electrode on a connection part of a capacitor assembly according to an example embodiment of the present disclosure. DETAILED DESCRIPTION

[0021] Hereinafter, embodiments of the present disclosure will be described as follows with reference to the accompanying drawings.

[0022] These embodiments are described in sufficient detail to enable those skilled in the art to practice the present invention. It should be understood that the various embodiments of the present invention, although different, are not necessarily mutually exclusive. For example, without departing from the spirit and scope of the present disclosure, the structure, shape and size described as an example in the embodiments of the present disclosure may be implemented in another example embodiment. For clarity of description, the shape and size of the elements in the drawings may be exaggerated, and the same elements will be represented by the same reference numerals.

[0023] For clarity of description, some elements may be omitted or briefly shown, and the thickness of elements may be exaggerated to clearly indicate layers and regions. It will be understood that when a part "includes" an element, it may also include other elements without excluding other elements unless otherwise specified.

[0024] In the drawings, the X direction may be defined as the second direction, L direction or length direction, the Y direction may be defined as the third direction, W direction or width direction, and the Z direction may be defined as the first direction, T direction or thickness direction.

[0025] Figure 1 is a perspective view illustrating a capacitor assembly according to example embodiments.

[0026] Figure 2 It is shown Figure 1 A perspective view of the subject shown in FIG.

[0027] Figure 3 It is shown Figure 1 A perspective view of a stacked portion is shown in FIG.

[0028] Figure 4 It is along Figure 1 A cross-sectional view taken along line II' in FIG.

[0029] Figure 5A and Figure 5B is Figure 1 2 is a cross-sectional view taken in the X direction and the Y direction shown in FIG. Figure 5A is a cross-sectional view showing a first inner electrode, Figure 5B is a cross-sectional view showing a second inner electrode.

[0030] Figure 6 is a diagram illustrating a metal particle, a surface of which is coated with graphene, according to example embodiments.

[0031] Figure 7 is a diagram illustrating an external electrode including metal particles, a surface of each of which is coated with graphene, according to example embodiments.

[0032] In the following description, reference will be made to Figures 1 to 7 The capacitor assembly is described in more detail.

[0033] The capacitor assembly 10 may include a body 100 including a laminated portion 110 in which a first internal electrode 121 and a second internal electrode 122 are laminated in a first direction (Z direction), and first and second connecting portions 141 and 142, which are respectively disposed on both surfaces of the laminated portion in a second direction (X direction) perpendicular to the first direction and are respectively connected to the first and second internal electrodes 121 and 122, and first and second external electrodes 151 and 152, which are respectively disposed on the first and second connecting portions 141 and 142. The first and second external electrodes 151 and 152 may include metal particles, and a surface of each of the metal particles is coated with one of graphene and carbon nanotubes.

[0034] The material of the metal particles is not limited to any specific material as long as the metal particles can be used for the external electrodes of the capacitor assembly. For example, the metal particles may include one or more materials selected from the group consisting of silver (Ag), palladium (Pd), gold (Au), platinum (Pt), nickel (Ni), copper (Cu), tin (Sn), tungsten (W), titanium (Ti) and alloys thereof, but the material of the metal particles is not limited thereto.

[0035] In example embodiments, the term “graphene” may refer to a graphene in which carbon atoms are connected by sp 2A material that is arranged in a hexagonal form on a two-dimensional phase and connected to each other, and may have a thickness corresponding to a carbon atom layer. Graphene may have a structure in which carbon atoms (carbon allotropes) separated from graphite having a three-dimensional structure may be connected to each other in the form of a hexagonal honeycomb, and may form a two-dimensional planar structure.

[0036] In example embodiments, graphene may be implemented by one or more materials selected from the group consisting of high quality graphene (HQG), graphene oxide (GO), and reduced graphene oxide (RGO), and the high quality graphene may mean graphene in which formation of domain boundaries is prevented.

[0037] In example embodiments, a carbon nanotube may refer to a nanotube in which carbon atoms are sp 2 Materials that form a nanostructure in a cylindrical shape are combined and may represent a carbon allotrope having a three-dimensional structure. The carbon nanotube may be implemented as a single-walled carbon nanotube (SWNT) and / or a multi-walled carbon nanotube (MWNT), but examples of the carbon nanotube are not limited thereto.

[0038] Figure 6 is a diagram illustrating metal particles coated with graphene according to example embodiments. Figure 6 , the metal particle 201, the surface of which is coated with the graphene 202, may include a structure in which a graphene 202 layer may be formed on the surface of the metal particle 201. The graphene layer may mean a coating layer formed using graphene.

[0039] The method for forming metal particles (whose surface is coated with graphene or carbon nanotubes) is not limited to any specific method. For example, metal particles can be formed by mixing metal particles with graphene and / or carbon nanotubes and grinding the mixture. When metal particles are mixed and ground with graphene and / or carbon nanotubes, metal particles and graphene and / or carbon nanotubes can move and can mix with each other with strong back and forth motion or rotational motion. Since graphene has an extremely thin planar structure and carbon nanotubes have an extremely fine linear structure, graphene and / or carbon nanotubes can be uniformly attached to the surface of metal particles by physical collision or electrostatic attraction. The grinding method is not limited to any specific method. For example, ball milling, jet milling, etc. can be used.

[0040] When the above-mentioned grinding method is used, graphene and carbon nanotubes can form a composite structure. The concept that graphene and carbon nanotubes can form a composite structure can mean that graphene and carbon nanotubes can be connected to each other in a mixed state, and the end of the carbon nanotube can be connected to the graphene. Considering the structural aspects of the carbon nanotube and graphene, the carbon nanotube and graphene can form a contact path between their particles, and therefore, a conductive path can be effectively formed.

[0041] Figure 7 It is shown Figure 4 An enlarged view of part A shown in FIG. Figure 7 An outer electrode including metal particles is shown, the surface of each of the metal particles being coated with graphene. Figure 7 , when the outer electrode is formed using a conductive paste including metal particles and the surface of each of the metal particles is coated with graphene, the graphene layer and / or the carbon nanotube layer 212 may be distributed between the metal particles 211. This is because, since the melting point of graphene and / or carbon nanotubes is 3000°C or higher, the graphene and / or carbon nanotubes will not be thermally decomposed or melted at the temperature of sintering the outer electrode, and the graphene and / or carbon nanotubes may be uniformly distributed in the outer electrode after the sintering process. Each carbon atom included in the graphene and / or carbon nanotubes may share half of a pair of electrons with adjacent carbon and may be combined with carbon, while uncombined electrons may easily move in the graphene and / or carbon nanotubes. Therefore, the metal particles (whose surfaces are coated with graphene and / or carbon nanotubes) may exhibit high conductivity. Furthermore, in the capacitor assembly in example embodiments, by applying metal particles, each of which has a surface coated with graphene and / or carbon nanotubes, to external electrodes, an electrical path may be improved so that an equivalent series resistance (ESR) may be reduced.

[0042] In example embodiments, the body 100 may include a stacking portion 110 and first and second connection portions 141 and 142 .

[0043] The shape of the body 100 may not be limited to any specific shape, and the body 100 may have a hexahedral shape or a shape similar to a hexahedron. Due to the shrinkage of the ceramic powder included in the body 100 during the sintering process, the body 100 may not have an accurate hexahedral shape including straight lines, but may have a generally hexahedral shape. The body 100 may have a first surface 1 and a second surface 2, a third surface 3 and a fourth surface 4, and a fifth surface 5 and a sixth surface 6, the first surface 1 and the second surface 2 are opposite to each other in the thickness direction (Z direction), the third surface 3 and the fourth surface 4 are connected to the first surface 1 and the second surface 2 and are opposite to each other in the length direction (X direction), and the fifth surface 5 and the sixth surface 6 are connected to the first surface 1 and the second surface 2 and the third surface 3 and the fourth surface 4 and are opposite to each other in the width direction (Y direction).

[0044] In example embodiments, in the stacked portion 110, the dielectric layers 111 and the first and second internal electrodes 121 and 122 may be alternately stacked, and the dielectric layers 111 and the first and second internal electrodes 121 and 122 may be stacked in the first direction. The plurality of dielectric layers 111 included in the stacked portion 110 may be in a sintered state, and the dielectric layers may be integrated so that it may be difficult to distinguish boundaries between adjacent dielectric layers without using a scanning electron microscope (SEM).

[0045] In example embodiments, the material of the dielectric layer 111 may not be limited to any specific material as long as sufficient capacitance can be obtained. For example, the dielectric layer 111 may be formed using a barium titanate material, a perovskite material compound containing lead (Pb), a strontium titanate material, or the like.

[0046] Depending on the intended purpose, barium titanate (BaTiO 3 ) powder or the like including various ceramic additives, organic solvents, coupling agents, dispersants, etc. may be used as the material of the dielectric layer 111 .

[0047] The stacked portion may be formed by alternately stacking ceramic green sheets on which the first internal electrodes 121 are printed and ceramic green sheets on which the second internal electrodes 122 are printed in a thickness direction (Z direction).

[0048] In example embodiments, the plurality of internal electrodes 121 and 122 may be opposite to each other with the dielectric layer 111 interposed therebetween. The internal electrodes 121 and 122 may include first and second internal electrodes 121 and 122 alternately disposed and opposite to each other with the dielectric layer 111 interposed therebetween.

[0049] The first internal electrode 121 may be exposed only to one surface of the laminate 110 in the second direction (X direction), and a portion of the first internal electrode 121 exposed to the one surface in the second direction (X direction) may be connected to the metal layer 141a of the first connection portion 141. The second internal electrode 122 may be exposed to the other surface of the laminate 110 in the second direction (X direction), and a portion of the second internal electrode 122 exposed to the other surface in the second direction (X direction) may be connected to the metal layer 142a of the second connection portion 142. The first internal electrode 121 and the second internal electrode 122 may be electrically isolated from each other by the dielectric layer 111 interposed therebetween.

[0050] The first and second internal electrodes 121 and 122 may be formed using a conductive paste including one or more materials such as silver (Ag), palladium (Pd), gold (Au), platinum (Pt), nickel (Ni), tin (Sn), copper (Cu), tungsten (W), titanium (Ti), and alloys thereof. Screen printing, gravure printing, etc. may be used as a method of printing the conductive paste, but the printing method is not limited thereto.

[0051] The average thickness of the first internal electrode 121 and the second internal electrode 122 may be 0.4 μm or less. The average thickness of the first internal electrode 121 and the second internal electrode 122 may be an average value of thicknesses measured in five different positions of the sintered internal electrode. The lower limit of the average thickness of the first internal electrode 121 and the second internal electrode 122 is not limited to any specific size, for example, may be 0.01 μm or more. That is, the average thickness of the first internal electrode 121 and the second internal electrode 122 may be in the range from 0.01 μm to 0.4 μm.

[0052] In example embodiments, the first connection portion 141 may include a metal layer 141a disposed on the laminate 110 and a ceramic layer 141b disposed on the metal layer 141a, and the second connection portion 142 may include a metal layer 142a disposed on the laminate 110 and a ceramic layer 142b disposed on the metal layer 142a.

[0053] The metal layers 141 a and 142 a may be disposed on one surface and the other surface of the stack part 110 in the second direction (X direction), respectively, and may be connected to the first and second internal electrodes 121 and 122 , respectively.

[0054] The metal layers 141a and 142a may include a metal material having high conductivity, and in order to improve electrical connectivity with the first and second internal electrodes 121 and 122, the metal layers 141a and 142a may include the same metal as that included in the first and second internal electrodes 121 and 122. For example, the metal layers 141a and 142a may include one or more of silver (Ag), palladium (Pd), gold (Au), platinum (Pt), nickel (Ni), tin (Sn), copper (Cu), tungsten (W), titanium (Ti), and alloys thereof.

[0055] The metal layers 141a and 142a may be provided in the form of sintered electrodes and may be sintered simultaneously with the stack 110. In this case, before sintering, the metal layers 141a and 142a may include organic materials such as metal particles and a binder and may be transferred on the stack 110, and the organic materials may be removed after the sintering process, etc.

[0056] The thickness ta of the metal layer is not limited to any specific size, and may be 1 μm to 10 μm. The thickness ta of the metal layer may refer to a size of the metal layer in the second direction (X direction).

[0057] The ceramic layers 141b and 142b may be disposed on the metal layers 141a and 142a, and may improve sealing properties so that moisture or plating liquid may be significantly reduced from penetrating into the body. The ceramic layers 141b and 142b may be configured not to cover the surfaces of the metal layers 141a and 142a in the first direction (Z direction) and the third direction (Y direction).

[0058] The ceramic layers 141b and 142b may be formed using a ceramic material such as barium titanate, etc. In this case, the ceramic layers 141b and 142b may include the same ceramic material as that included in the dielectric layer 111 or may be formed using the same material as that of the dielectric layer 111.

[0059] The ceramic layers 141b and 142b may be formed on the metal layers 141a and 142a through a transfer process, and may be subjected to a sintering process after the transfer process. It may be more preferable that the ceramic layers 141b and 142b have high adhesion for the transfer process before sintering, and therefore, the ceramic layers 141b and 142b may include a relatively large amount of organic material such as a binder. In this case, since the organic material may partially remain after the sintering process, the ceramic layers 141b and 142b may include a larger amount of organic material than the organic material included in the dielectric layer 111.

[0060] The thickness tb of the ceramic layer is not limited to any specific size, and may be, for example, 3 μm to 15 μm. The thickness tb of the ceramic layer may refer to a size of the ceramic layer in the second direction (X direction).

[0061] In example embodiments, the first connection portion 141 and the second connection portion 142 may be formed by a transfer sheet method and may have a uniform thickness. Therefore, the ratio of the minimum value to the maximum value of the thickness of each of the first connection portion 141 and the second connection portion 142 may be 0.9 to 1.0. The thickness of each of the first connection portion 141 and the second connection portion 142 may represent the size of each of the first connection portion 141 and the second connection portion 142 in the second direction (X direction).

[0062] In example embodiments, each of the corners of the body 100 may have a rounded shape (eg, an arc shape) on a cross-sectional surface taken in the first direction and the second direction. By configuring each corner of the body to have a rounded shape, each of the external electrodes 151 and 152 may have a reduced and uniform thickness.

[0063] When each of the corners of the body has an angled shape, a chipping defect caused by collision between sheets, cracking of the corners may occur during the process of manufacturing the MLCC, which may cause appearance defects and may deteriorate moisture-proof reliability. To solve this problem, generally, the corners of the body may be ground to have a rounded shape to prevent the thickness of the external electrode on the corner from being reduced and to prevent the chipping defect.

[0064] However, by grinding the corners of the body, the inner electrode may be exposed or other problems may occur, so it may be difficult to ensure a sufficiently rounded shape on each of the corners of the body in the general capacitor assembly. In addition, in order to prevent the exposure of the inner electrode, when the thickness of the protective part increases, the capacitance per unit volume of the capacitor assembly may decrease.

[0065] In example embodiments, by respectively disposing the first connection portion 141 and the second connection portion 142 on both surfaces of the laminate 110 in the second direction (X direction), a sufficiently rounded shape can be formed on the corners of the body 100. Therefore, the thickness of the external electrode on each corner can be prevented from being reduced without reducing the capacitance per unit volume, and the peeling defect can be prevented.

[0066] In example embodiments, the stack 110 may include a capacitor forming portion including a first internal electrode 121 and a second internal electrode 122 opposite to each other with a dielectric layer 111 interposed therebetween, and a protective portion 112 disposed on upper and lower portions of the capacitor forming portion.

[0067] The upper and lower protecting portions may have the same composition as that of the dielectric layer 111 and may be formed by stacking at least one dielectric layer including no internal electrode on an upper portion of an uppermost internal electrode of a capacitance forming portion and on a lower portion of a lowermost internal electrode.

[0068] The upper and lower protecting portions 112 may prevent damage to the internal electrodes caused by physical or chemical stress.

[0069] The thickness tp of each of the upper and lower protecting portions 112 may not be limited to any specific size, and in example embodiments, since a sufficiently rounded shape can be formed on each corner of the body 100 by providing the connecting portions 141 and 142 on the stacking portion 110, the capacitance per unit volume of the capacitor assembly 10 can be increased by significantly reducing the thickness tp of each of the upper and lower protecting portions 112.

[0070] For example, in example embodiments, even when the thickness tp is 20 μm or less, a sufficient round shape can be formed and the inner electrode can also be protected. Therefore, the capacitance per unit volume can be increased. Therefore, when the thickness tp is 20 μm or less, the above effect can be more significant.

[0071] The lower limit of the thickness tp is not limited to any specific size and may be selected in consideration of the curvature radius R1 of the corners on the cross-sectional surface of the body taken in the first and second directions. For example, the lower limit of the thickness tp may be 5 μm or more.

[0072] The thickness tp of each of the upper and lower protecting portions 112 may represent a dimension of each of the upper and lower protecting portions 112 in the first direction (Z direction).

[0073] Reference Figure 4 , when the thickness of each of the upper protecting portion and the lower protecting portion 112 is defined as tp, and the curvature radius of the corners on the cross-sectional surfaces (ZX cross-sectional surface and LT cross-sectional surface) of the body 100 intercepted in the first direction and the second direction is defined as R1, R1 / tp may be greater than or equal to 0.3 and less than or equal to 1.4.

[0074] When R1 / tp is less than 0.3, a sufficiently rounded shape may not be formed, and thus, a peeling defect may occur, or the thickness of the external electrode on the corner may be reduced.

[0075] When R1 / tp exceeds 1.4, a short circuit caused by exposure of the inner electrode may occur, or it may be difficult to form the outer electrode. The short circuit caused by exposure of the inner electrode may refer to a phenomenon in which the first inner electrode 121 may be exposed to the surface on which the second outer electrode 152 is disposed and may be connected to the second outer electrode 152, or the second inner electrode 122 may be exposed to the surface on which the first outer electrode 151 is disposed and may be connected to the first outer electrode 151, due to the corner of the body being ground.

[0076] R1 / tp may be greater than or equal to 1.0 and less than or equal to 1.4.

[0077] When the connection parts 141 and 142 are not provided and R1 / tp is controlled to be greater than 1.0, it is very likely that a short circuit caused by exposure of the inner electrode may occur. However, when the connection parts 141 and 142 are provided as in the example embodiment, even when R1 / tp is controlled to be greater than 1.0 and less than or equal to 1.4, the possibility of a short circuit caused by exposure of the inner electrode can be significantly reduced.

[0078] A rounded shape of each of the corners on the cross-sectional surface of the body 100 taken in the first direction and the second direction may be formed on the connection parts 141 and 142, and as shown in FIG. Figure 3 and Figure 4 As shown, the circular shape may extend to a portion of the laminate 110 .

[0079] In example embodiments, the first and second edge portions 131 and 132 may be respectively disposed on two surfaces (fifth and sixth surfaces) of the laminate part 110 in a third direction (Y direction) perpendicular to the first and second directions.

[0080] In a conventional capacitor assembly, the area of ​​the dielectric layer may be configured to be larger than the area of ​​the inner electrode, and the edge region may be formed on the remaining peripheral portion except for the portion of the inner electrode connected to the outer electrode. However, in this case, when tens to hundreds of dielectric layers are stacked, the dielectric layer may be extended to fill the gap (e.g., thickness difference), and thus, the inner electrode may be bent. When the inner electrode is bent, the breakdown voltage (BDV) characteristics in the corresponding portion may be reduced.

[0081] Therefore, in the capacitor assembly of the exemplary embodiment, the gap caused by the inner electrode can be prevented by removing the edge regions on both surfaces of the laminate 110 in the third direction, and the inner electrode can be prevented from being bent. Therefore, the problem of reduction in breakdown voltage (BDV) characteristics can be prevented, thereby improving the reliability of the capacitor assembly.

[0082] In addition, by providing the first edge portion 131 and the second edge portion 132 on both surfaces of the laminate 110 in the third direction, the internal electrodes can be protected. In addition, since the first edge portion 131 and the second edge portion 132 are formed separately, it is not necessary to consider manufacturing errors such as misalignment of the internal electrodes. Therefore, since the thickness Wm of each of the first edge portion 131 and the second edge portion 132 can be configured to be smaller than the thickness of the edge region in a general capacitor assembly, the capacitance per unit volume of the capacitor assembly can be increased.

[0083] Therefore, when the body 100 includes the first edge portion 131 and the second edge portion 132, the first internal electrode 121 may be exposed to both surfaces of the laminate 110 in the third direction and one surface of the laminate 110 in the second direction, and a portion thereof exposed to the one surface in the second direction may be connected to the first connection portion 141. In addition, the second internal electrode 122 may be exposed to both surfaces of the laminate 110 in the third direction and the other surface of the laminate 110 in the second direction, and a portion thereof exposed to the other surface in the second direction may be connected to the second connection portion 142.

[0084] The first edge portion 131 and the second edge portion 132 may be formed using an insulating material, and may be formed using a ceramic material such as barium titanate. In this case, the first edge portion 131 and the second edge portion 132 may include the same ceramic material as the material included in the dielectric layer 111, or may be formed using the same material as the material included in the dielectric layer 111.

[0085] The method of forming the first edge portion 131 and the second edge portion 132 may not be limited to any specific method. For example, the first edge portion 131 and the second edge portion 132 may be formed by coating a slurry including ceramic or laminating dielectric sheets along the third direction on both surfaces of the laminate in the third direction.

[0086] The first edge portion 131 and the second edge portion 132 may also be formed by transferring the dielectric sheet using the above transfer process. Therefore, each of the first edge portion 131 and the second edge portion 132 may have a uniform thickness. When the thickness of each of the first edge portion 131 and the second edge portion 132 is defined as Wm, the ratio of the minimum value to the maximum value of the thickness Wm may be 0.9 to 1.0.

[0087] When the first edge portion 131 and the second edge portion 132 are formed by transferring the dielectric sheet, it may be more preferable that the first edge portion 131 and the second edge portion 132 have high adhesion for the transfer process before sintering. To this end, the first edge portion 131 and the second edge portion 132 may include a relatively large amount of organic material such as an adhesive. In this case, since the organic material may partially remain after the sintering process, the first edge portion 131 and the second edge portion 132 may include a larger amount of organic material than the amount of organic material included in the dielectric layer 111.

[0088] The thickness Wm of each of the first edge portion 131 and the second edge portion 132 may not be limited to any specific size. In example embodiments, since a sufficient round shape can be formed on the corner of the body by providing the connection portions 141 and 142 on the stack portion 110, the capacitance per unit volume of the capacitor assembly can be increased by significantly reducing the thickness Wm. For example, in example embodiments, even when the thickness Wm is 15 μm or less, a sufficient round shape can be formed, and the internal electrodes 121 and 122 can also be protected, thereby increasing the capacitance per unit volume of the capacitor assembly.

[0089] The lower limit of the thickness Wm may not be limited to any specific size, and may be selected in consideration of the radius of curvature R2 of the corners on the cross-sectional surfaces (XY cross-sectional surface and LW cross-sectional surface) of the body taken in the second direction and the third direction. For example, the thickness Wm may be 5 μm or more. The thickness Wm of each of the first edge portion 131 and the second edge portion 132 may represent the size of each of the first edge portion 131 and the second edge portion 132 in the third direction (Y direction).

[0090] Reference Figure 5A and Figure 5B , when the thickness of each of the first edge portion 131 and the second edge portion 132 is defined as Wm, and the radius of curvature of the corners on the cross-sectional surfaces (XY cross-sectional surface and LW cross-sectional surface) of the body taken in the second direction and the third direction is defined as R2, R2 / Wm may be greater than or equal to 0.3 and less than or equal to 1.4. When R2 / Wm is less than 0.3, a sufficient circular shape may not be formed, so that a peeling defect may occur or the thickness of the outer electrode on the corner may be reduced. When R2 / Wm exceeds 1.4, a short circuit caused by exposure of the inner electrode may occur, or it may be difficult to form the outer electrode. The short circuit caused by exposure of the inner electrode may refer to a phenomenon in which, due to the grinding of the corner of the body, the first inner electrode 121 may be exposed to the surface on which the second outer electrode 152 is disposed and may be connected to the second outer electrode 152, or the second inner electrode 122 may be exposed to the surface on which the first outer electrode 151 is disposed and may be connected to the first outer electrode 151.

[0091] R2 / Wm may be greater than 1.0 and less than or equal to 1.4.

[0092] When the connection portions 141 and 142 are not provided and R2 / Wm is controlled to be greater than 1.0, it is likely that a short circuit caused by exposure of the internal electrode may occur, whereas when the connection portions 141 and 142 are provided as in the example embodiment, the possibility of a short circuit caused by exposure of the internal electrode may be significantly reduced even when R2 / Wm is controlled to be greater than 1.0 and less than or equal to 1.4.

[0093] In order to easily perform the grinding process, the curvature radius R2 of the corners on the cross-sectional surface of the body taken in the second direction and the third direction may be configured to be the same as the curvature radius R1 of the corners on the cross-sectional surface of the body taken in the first direction and the second direction, but example embodiments thereof are not limited thereto. The corners of the body may be ground so that R2 and R1 may be configured to be different.

[0094] Since the first connection portion 141 and the second connection portion 142 are formed using a transfer process after the first edge portion 131 and the second edge portion 132 are formed on the stacking portion 110, the first connection portion 141 can be configured to cover one surface of the first edge portion 131 and the second edge portion 132 in the second direction (X direction), and the second connection portion 142 can be configured to cover the other surface of the first edge portion 131 and the second edge portion 132 in the second direction (X direction).

[0095] The first connection portion 141 may be disposed within one surface of the laminated portion 110 and the first edge portion 131 and the second edge portion 132 in the second direction (X direction), and the second connection portion 142 may be disposed within the other surface of the laminated portion 110 and the first edge portion 131 and the second edge portion 132 in the second direction (X direction). Therefore, the first connection portion 141 and the second connection portion 142 may not extend to both surfaces of the laminated portion 110 in the first direction (Z direction), and may not extend to both surfaces of the first edge portion 131 and the second edge portion 132 in the third direction (Y direction).

[0096] The first and second external electrodes 151 and 152 may be disposed on the first and second connection parts 141 and 142, respectively. The first external electrode 151 may be connected to the first internal electrode 121 through the metal layer 141a of the first connection part 141, and the second external electrode 152 may be connected to the second internal electrode 122 through the metal layer 142a of the second connection part 142.

[0097] The first external electrode 151 and the second external electrode 152 may extend to both surfaces of the first connection portion 141 and the second connection portion 142 in the first direction (Z direction), respectively, and the metal layer 141a of the first connection portion 141 and the metal layer 142a of the second connection portion 142 may be exposed to the surfaces of the first connection portion 141 and the second connection portion 142 in the first direction (Z direction), respectively, and may be connected to the first external electrode 151 and the second external electrode 152, respectively. The first external electrode 151 and the second external electrode 152 may also extend to both surfaces of the first connection portion 141 and the second connection portion 142 in the third direction (Y direction), respectively, and the metal layer 141a of the first connection portion 141 and the metal layer 142a of the second connection portion 142 may also be exposed to the surfaces of the first connection portion 141 and the second connection portion 142 in the third direction (Y direction), respectively, and may be connected to the first external electrode 151 and the second external electrode 152, respectively.

[0098] The first and second external electrodes 151 and 152 may extend to a portion of the first and second surfaces 1 and 2 of the body. The first and second external electrodes 151 and 152 may also extend to a portion of the fifth and sixth surfaces 5 and 6 of the body.

[0099] The method of forming the first external electrode 151 and the second external electrode 152 may not be limited to any specific method. For example, the first external electrode 151 and the second external electrode 152 may be formed by dipping the body into a paste including a conductive metal and glass. The conductive metal may include the above-mentioned metal particles and / or metal particles each of which has a surface coated with graphene.

[0100] In example embodiments, since each of the corners of the body 100 has a rounded shape, even when the external electrodes are formed using a dipping process, a phenomenon in which the thickness of each of the external electrodes 151 and 152 at the corners of the body 100 is reduced may be prevented.

[0101] Therefore, when the thickness of each of the first and second external electrodes 151 and 152 is defined as tc, a ratio of a minimum value to a maximum value of the thickness tc may be 0.8 to 1.0.

[0102] In order to improve the mounting property with the substrate, a plating layer may be formed on the first external electrode 151 and the second external electrode 152. For example, the plating layer may be implemented by Ni plating or Sn plating, and the Ni plating layer and the Sn plating layer may be sequentially formed on the external electrodes. Alternatively, the first external electrode 151 and the second external electrode 152 may include a plurality of Ni plating layers and / or a plurality of Sn plating layers.

[0103] Figures 8 to 11 is a diagram illustrating a process of forming a connection portion 141 of a capacitor assembly through a transfer process according to example embodiments.

[0104] like Figure 8 As shown, in the process of transferring the metal layer 141a, the metal layer sheet 140a may be arranged on the support frame 300, and the laminate 110 may be pressed onto the metal layer sheet 140a so that the metal layer 141a may be attached to the surface of the laminate 110. The metal layer sheet 140a that has not yet been sintered may include components such as an adhesive, an organic solvent, and the like.

[0105] like Fig. 9 As shown, the ceramic sheet 140b may be arranged on the support frame 300, and the laminate 110 may be pressed to the ceramic sheet 140b so that the ceramic sheet 140b may be attached to the surface of the metal layer 141a. The ceramic sheet 140b that has not yet been sintered may include components such as an adhesive, an organic solvent, and the like.

[0106] The same process may be performed on another surface opposite to the surface on which the metal layer 141a and the ceramic layer 141b are disposed to form the metal layer 142a and the ceramic layer 142b, thereby manufacturing a Fig.11 The main body 100 is shown.

[0107] Each of the corners of the body may be processed to have a rounded shape by performing a grinding process, and the external electrodes 151 and 152 may be formed by dipping the ground body 100 into a conductive paste, thereby manufacturing the capacitor assembly 10 .

[0108] like Fig.10 As shown, the first connection portion 141 may also be formed by stacking the ceramic layer sheet 140 b and the metal layer sheet 140 a on the support frame 300 and performing a transfer process once (instead of transferring the metal layer and the ceramic layer separately).

[0109] Once the body 100 is formed, the external electrodes 151 and 152 are formed on the respective opposite ends of the body 100 by, for example, dipping the body into a conductive paste 400 having a material for the external electrodes 151 and 152. Fig.12 The range in which the external electrodes 151 and 152 are provided on the surface of the body 100 connecting the corresponding opposing surfaces (ie, the edge portion and the cover portion (protection portion)) is determined by the range or depth in which the body is immersed in the conductive paste 400.

[0110] According to the aforementioned example embodiments, by providing the connection portion on the stacked portion, the capacitance per unit volume of the capacitor assembly may be increased, and the moisture-proof reliability may be improved.

[0111] In addition, each of the corners of the body may have a sufficiently rounded shape, and when each of the corners of the body has a sufficiently rounded shape, each of the external electrodes may have a uniform and reduced thickness.

[0112] Furthermore, when the edge portions are provided on both surfaces of the laminate portion, the capacitance per unit volume of the capacitor assembly can be increased.

[0113] Furthermore, since the external electrode includes metal particles, a surface of each of the metal particles is coated with at least one of graphene and carbon nanotubes, resistance may be reduced, thereby reducing ESR.

[0114] While example embodiments have been shown and described above, it will be apparent to those skilled in the art that modifications and variations may be made without departing from the scope of the invention as defined by the appended claims.

Claims

1. A capacitor assembly, comprising: A subject, the subject comprising: a stacked portion including a first internal electrode and a second internal electrode facing each other and stacked in a first direction, with a dielectric layer interposed between the first internal electrode and the second internal electrode, and first and second connecting portions, respectively disposed on opposite surfaces of the laminate in a second direction perpendicular to the first direction and respectively connected to the first and second internal electrodes; and A first external electrode and a second external electrode are respectively disposed on the first connecting portion and the second connecting portion, wherein the first external electrode and the second external electrode include metal particles and glass, and a surface of at least one of the metal particles is coated with at least one of graphene and carbon nanotubes, Wherein, a ratio of a minimum value to a maximum value of a thickness of at least one of the first connecting portion and the second connecting portion is 0.9 to 1.

0.

2. The capacitor assembly according to claim 1, wherein: The first connection portion and the second connection portion include a metal layer disposed on the stacked portion and a ceramic layer disposed on the metal layer, respectively.

3. The capacitor assembly according to claim 2, wherein: The thickness of the metal layer ranges from 1 μm to 10 μm.

4. The capacitor assembly according to claim 2, wherein: The thickness of the ceramic layer is in the range from 3 μm to 15 μm.

5. The capacitor assembly according to claim 1, wherein: A ratio of a minimum value to a maximum value of a thickness of each of the first connection portion and the second connection portion is 0.9 to 1.

0.

6. The capacitor assembly according to claim 2, wherein: The first connection portion and the second connection portion are formed by transferring a ceramic layer having a sheet form and a metal layer having a sheet form in the second direction.

7. The capacitor assembly according to claim 1, wherein: Each of the corners of the body has a rounded shape.

8. The capacitor assembly according to claim 1, wherein: An average thickness of the first and second internal electrodes ranges from 0.01 μm to 0.4 μm.

9. The capacitor assembly according to claim 1, wherein: The stacked portion includes a capacitor forming portion and an upper protective portion and a lower protective portion, the capacitor forming portion includes the first internal electrode and the second internal electrode opposite to each other and the dielectric layer is interposed between the first internal electrode and the second internal electrode, and the upper protective portion and the lower protective portion are respectively arranged on the upper portion and the lower portion of the capacitor forming portion.

10. The capacitor assembly according to claim 9, wherein: R1 / tp ranges from 0.3 to 1.4, wherein tp is a thickness of each of the upper and lower protecting portions, and R1 is a radius of curvature of each of corners on a cross-sectional surface of the body taken in the first and second directions.

11. The capacitor assembly according to claim 10, wherein: The thickness tp is 20 μm or less.

12. The capacitor assembly of claim 1, further comprising: The first edge portion and the second edge portion are respectively provided on a fifth surface and a sixth surface of the stacked portion, and the fifth surface and the sixth surface are opposite to each other in a third direction perpendicular to the first direction and the second direction.

13. The capacitor assembly of claim 12, wherein: R2 / Wm is in the range from 0.3 to 1.4, wherein Wm is the thickness of each of the first edge portion and the second edge portion, and R2 is the radius of curvature of each of the corners on the cross-sectional surface of the body taken in the second direction and the third direction.

14. The capacitor assembly according to claim 1, in, The body includes a first surface and a second surface opposite to each other in the first direction, a third surface and a fourth surface opposite to each other in the second direction, and a fifth surface and a sixth surface opposite to each other in a third direction perpendicular to the first direction and the second direction, wherein the first external electrode and the second external electrode extend to the first surface, the second surface, the fifth surface, and the sixth surface, and The first connection portion and the second connection portion are connected to the first external electrode and the second external electrode respectively.

15. The capacitor assembly of claim 1, wherein: A ratio of a minimum value to a maximum value of a thickness tc, where tc is a thickness of each of the first and second external electrodes, ranges from 0.8 to 1.

0.

16. A capacitor assembly comprising: A subject, the subject comprising: a stacked portion including a first internal electrode and a second internal electrode facing each other and stacked in a first direction, with a dielectric layer interposed between the first internal electrode and the second internal electrode, and first and second connecting portions, respectively disposed on opposite surfaces of the laminate in a second direction perpendicular to the first direction and respectively connected to the first and second internal electrodes; and A first external electrode and a second external electrode are respectively disposed on the first connecting portion and the second connecting portion, wherein the first external electrode and the second external electrode include metal particles and glass, and a surface of at least one of the metal particles is coated with at least one of graphene and carbon nanotubes, At least one of the first connection portion and the second connection portion includes a metal layer disposed on the laminated portion and a ceramic layer disposed on the metal layer.

17. The capacitor assembly of claim 16, wherein: The first connection portion and the second connection portion each include a metal layer disposed on the laminated portion and a ceramic layer disposed on the metal layer.

18. The capacitor assembly of claim 17, wherein: The thickness of the metal layer ranges from 1 μm to 10 μm.

19. The capacitor assembly of claim 17, wherein: The thickness of the ceramic layer is in the range from 3 μm to 15 μm.

20. The capacitor assembly of claim 16, wherein: A ratio of a minimum value to a maximum value of a thickness of each of the first connection portion and the second connection portion is 0.9 to 1.

0.

21. The capacitor assembly of claim 17, wherein: The first connection portion and the second connection portion are formed by transferring a ceramic layer having a sheet form and a metal layer having a sheet form in the second direction.

22. The capacitor assembly of claim 16, wherein: Each of the corners of the body has a rounded shape.

23. The capacitor assembly of claim 16, wherein: An average thickness of the first and second internal electrodes ranges from 0.01 μm to 0.4 μm.

24. The capacitor assembly of claim 16, wherein: The stacked portion includes a capacitor forming portion and an upper protective portion and a lower protective portion, the capacitor forming portion includes the first internal electrode and the second internal electrode opposite to each other and the dielectric layer is interposed between the first internal electrode and the second internal electrode, and the upper protective portion and the lower protective portion are respectively arranged on the upper portion and the lower portion of the capacitor forming portion.

25. The capacitor assembly of claim 24, wherein: R1 / tp ranges from 0.3 to 1.4, wherein tp is a thickness of each of the upper and lower protecting portions, and R1 is a radius of curvature of each of corners on a cross-sectional surface of the body taken in the first and second directions.

26. The capacitor assembly of claim 25, wherein: The thickness tp is 20 μm or less.

27. The capacitor assembly of claim 16, further comprising: The first edge portion and the second edge portion are respectively provided on a fifth surface and a sixth surface of the stacked portion, and the fifth surface and the sixth surface are opposite to each other in a third direction perpendicular to the first direction and the second direction.

28. The capacitor assembly of claim 27, wherein: R2 / Wm is in the range from 0.3 to 1.4, wherein Wm is the thickness of each of the first edge portion and the second edge portion, and R2 is the radius of curvature of each of the corners on the cross-sectional surface of the body taken in the second direction and the third direction.

29. The capacitor assembly of claim 16, in, The body includes a first surface and a second surface opposite to each other in the first direction, a third surface and a fourth surface opposite to each other in the second direction, and a fifth surface and a sixth surface opposite to each other in a third direction perpendicular to the first direction and the second direction, wherein the first external electrode and the second external electrode extend to the first surface, the second surface, the fifth surface, and the sixth surface, and The first connection portion and the second connection portion are connected to the first external electrode and the second external electrode respectively.

30. The capacitor assembly of claim 16, wherein: A ratio of a minimum value to a maximum value of a thickness tc, where tc is a thickness of each of the first and second external electrodes, ranges from 0.8 to 1.0.

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