Multilayer electronic component

Abstract

To suppress arc discharge that can occur when high voltage is applied to a multilayer ceramic capacitor.SOLUTION: A multilayer electronic component includes: a main body including a dielectric layer and internal electrodes disposed alternately in a first direction with the dielectric layer held therebetween, and including a first surface and a second surface facing each other in the first direction, a third surface and a fourth surface connected to the first surface and the second surface and facing each other in a second direction, and a fifth surface and a sixth surface connected to the first to fourth surfaces and facing each other in a third direction; and an external electrode disposed on the third surface and the fourth surface. The main body includes a capacitance forming part corresponding to a region where the dielectric layer and the internal electrodes are disposed overlapping with each other in the first direction, and a cover part 112 and the like disposed on one surface and the other surface of the capacitance forming part in the first direction. A surface of the cover part includes a flat part 11 forming the first surface and the second surface, a projection part 12 projecting in the first direction from the first surface or the second surface, and a groove part 13 depressed in the first direction from the first surface or the second surface. One end of the projection part is disposed on the groove part apart from the groove part.SELECTED DRAWING: Figure 6

Description

[Technical field]

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

[0002] Multilayer ceramic capacitors (MLCCs), a type of multilayer electronic component, are chip-type capacitors that are mounted on printed circuit boards of various electronic products such as visual devices such as liquid crystal displays (LCDs) and plasma display panels (PDPs), computers, smartphones, mobile phones, and infotainment systems to charge and discharge electricity.

[0003] Recently, with the expansion of the electric vehicle market, the use of high-voltage multilayer ceramic capacitors in circuits such as on-board chargers (OBCs) and DC-DC converters for electric vehicles is expanding. When high voltage is applied to a multilayer ceramic capacitor, an electric field may be formed across the dielectric surface of the cover due to charge charging near the interface between the external electrode and cover of the multilayer ceramic capacitor, which may cause an arc discharge in the multilayer ceramic capacitor. This arc discharge may cause damage to the surface of the multilayer ceramic capacitor and may be a major cause of reduced reliability.

[0004] Therefore, there is a need for an improved structure that can suppress arc discharge that may occur when a high voltage is applied to a multilayer ceramic capacitor. Summary of the Invention [Problem to be solved by the invention]

[0005] One of the various objects of the present invention is to suppress arcing that can occur when high voltages are applied to a multilayer ceramic capacitor.

[0006] One of the various objectives of the present invention is to solve the problem of reduced moisture resistance reliability that can occur when the surface shape of the cover part is excessively controlled in order to suppress arc discharge that can occur when high voltage is applied to the capacitor.

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

[0008] A multilayer electronic component according to one embodiment of the present invention includes a main body including dielectric layers and internal electrodes alternately arranged in a first direction with the dielectric layers sandwiched therebetween, the main body including first and second surfaces facing each other in the first direction, third and fourth surfaces connected to the first and second surfaces and facing each other in the second direction, and fifth and sixth surfaces connected to the first to fourth surfaces and facing each other in the third direction, and external electrodes arranged on the third and fourth surfaces, the main body including a capacitance forming portion which is a region in which the dielectric layers and the internal electrodes are arranged to overlap in the first direction, and a cover portion arranged on one and the other surfaces of the capacitance forming portion in the first direction, the surface of the cover portion including a flat portion forming the first surface and the second surface, a protrusion protruding from the first surface or the second surface in the first direction, and a groove portion recessed from the first surface or the second surface in the first direction, one end of the protrusion being spaced apart from the groove portion and arranged on the groove portion. Effect of the Invention

[0009] One of the various advantages of the embodiments of the present invention is that by controlling the microstructure of the surface of the cover part and increasing the creepage distance, the arc discharge phenomenon that can occur when high voltage is applied to a multilayer electronic component is suppressed.

[0010] One of the various effects of the embodiments of the present invention is that by controlling the microstructure of the surface of the cover, it is possible to suppress the arc discharge phenomenon that can occur when high voltage is applied to a multilayer electronic component, while at the same time preventing a decrease in moisture resistance reliability.

[0011] However, the various yet significant advantages and effects of the embodiments of the present invention are not limited to the above, and can be more easily understood in the course of describing specific embodiments of the present invention. [Brief description of the drawings]

[0012] [Figure 1] 1 is a perspective view showing a schematic configuration of a multilayer electronic component according to an embodiment of the present invention; [Diagram 2] 2 is a cross-sectional view taken along line II' in FIG. [Diagram 3] 2 is a cross-sectional view taken along line II-II' in FIG. [Figure 4] FIG. 2 is an exploded perspective view showing the configuration of a main body of the multilayer electronic component. [Diagram 5] 1 is a schematic diagram showing clearance and creepage distance between a conductive material and an insulating material; [Figure 6] 3 is a schematic diagram showing an enlarged view of the surface (areas P1 and P2 in FIG. 2) of a cover part according to one embodiment. FIG. [Figure 7] FIG. 7 is a schematic diagram showing a modified example of FIG. 6. [Figure 8] FIG. 7 is a schematic diagram showing a modified example of FIG. 6. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, the embodiments of the present invention will be described with reference to specific embodiments and the accompanying drawings. However, the embodiments of the present invention can be modified into several other forms, and the scope of the present invention is not limited to the embodiments described below. Furthermore, the embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art. Therefore, the shapes and sizes of elements in the drawings may be enlarged or reduced (or highlighted or simplified) for clearer explanation, and elements indicated by the same reference numerals in the drawings are the same elements.

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

[0015] In the drawings, a first direction is a direction in which first and second internal electrodes are alternately arranged with a dielectric layer therebetween, or a thickness (T) direction, and among second and third directions perpendicular to the first direction, the second direction can be defined as a length (L) direction and the third direction can be defined as a width (W) direction.

[0016] FIG. 1 is a perspective view showing a schematic configuration of a multilayer electronic component according to an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along line I-I' in FIG. 1, FIG. 3 is a cross-sectional view taken along line II-II' in FIG. 1, FIG. 4 is an exploded perspective view showing the shape of a main body of the multilayer electronic component, FIG. 5 is a schematic diagram showing the clearance and creepage distance between a conductive material and an insulating material, and FIG. 6 is a schematic diagram showing an enlarged view of the surface of a cover part according to an embodiment (areas P1 and P2 in FIG. 2).

[0017] Hereinafter, a multilayer electronic component 100 according to one embodiment of the present invention and various embodiments thereof will be described in detail with reference to FIGS.

[0018] A multilayer electronic component 100 according to one embodiment of the present invention includes a main body including dielectric layers and internal electrodes alternately arranged in a first direction with the dielectric layers sandwiched therebetween, the main body including first and second surfaces facing each other in the first direction, third and fourth surfaces connected to the first and second surfaces and facing each other in the second direction, and fifth and sixth surfaces connected to the first to fourth surfaces and facing each other in the third direction, and external electrodes arranged on the third and fourth surfaces, the main body including a capacitance forming portion which is a region in which the dielectric layers and the internal electrodes are arranged to overlap in the first direction, and a cover portion arranged on one and the other surfaces of the capacitance forming portion in the first direction, the surface of the cover portion including a flat portion forming the first surface and the second surface, a protruding portion protruding from the first surface or the second surface in the first direction, and a groove portion recessed from the first surface or the second surface in the first direction, one end of the protruding portion being spaced apart from the groove portion and arranged on the groove portion.

[0019] The body 110 may include a dielectric layer 111 and internal electrodes 121 and 122 that are alternately arranged in a first direction with the dielectric layer 111 sandwiched therebetween.

[0020] Although there is no particular limitation on the specific shape of the body 110, the body 110 may be hexahedral or a similar shape as shown in the figure. Due to shrinkage of the ceramic powder contained in the body 110 during the firing process, the body 110 may not be a hexahedral shape with perfectly straight lines, but may be substantially hexahedral.

[0021] The main body 110 may include first and second surfaces 1, 2 facing each other in a first direction, third and fourth surfaces 3, 4 connected to the first and second surfaces 1, 2 and facing each other in the second direction, and fifth and sixth surfaces 5, 6 connected to the first and second surfaces 1, 2, connected to the third and fourth surfaces 3, 4, and facing each other in the third direction.

[0022] The plurality of dielectric layers 111 forming the body 110 are in a fired state, and the boundaries between adjacent dielectric layers 111 can be integrated so as to be difficult to confirm without using a scanning electron microscope (SEM). The number of stacked dielectric layers does not particularly need to be limited and can be determined in consideration of the size of the ceramic electronic component. For example, 300 or more dielectric layers can be stacked to form the body.

[0023] The raw materials for forming the dielectric layer 111 can be diverse according to the purpose. Specifically, ferroelectric BaTiO3 can be used as the material mainly for achieving a high capacitance per unit volume, and paraelectric CaZrO3 can be used as the material mainly for improving reliability in a high-temperature environment. Examples of materials for the BaTiO3 substrate include BaTiO3, (Ba 1-x Ca x )TiO3 (0 < x < 1) in which Ca (calcium), Zr (zirconium), etc. are partially solid-solved in BaTiO3, 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), etc. Examples of materials for the CaZrO3 substrate include (Ca 1-x Sr x )(Zr 1-y Ti y )O3 (0 < x < 1, 0 < y < 1).

[0024] In one embodiment, the dielectric layer 111 may be formed of a CaZrO3-based material in order to improve the high temperature and high pressure reliability of the multilayer electronic component 100. This can be similarly applied to the cover parts 112 and 113 described below, but when the cover parts 112 and 113 are formed of a CaZrO3-based material, the hardness of the cover parts 112 and 113 may be improved. This allows the structure of the flat part 11, the protruding part 12, and the groove part 13 to be smoothly formed as in one embodiment of the present invention.

[0025] When the dielectric layer 111 is formed as a CaZrO3-based material, the dielectric layer of the multilayer electronic component 100 may contain Ca and Zr, and may further contain Sr and Ti.

[0026] The average thickness td of the dielectric layer 111 is not particularly limited.

[0027] In order to achieve a smaller size and higher capacity of the multilayer electronic component 100, the average thickness td of the dielectric layer 111 can be 0.35 μm or less, and in order to improve the reliability of the multilayer electronic component 100 under high temperature and high pressure, the average thickness td of the dielectric layer 111 can be 3 μm or more.

[0028] The average thickness td of the dielectric layer 111 may refer to the average thickness of the dielectric layer 111 disposed between the first and second internal electrodes 121 and 122.

[0029] The average thickness td of the dielectric layer 111 can be measured by scanning an image of a cross section in the third and first directions (LT cross section) of the body 110 using a Scanning Electron Microscope (SEM).

[0030] For example, the average thickness td of the dielectric layer 111 may be calculated by measuring the thickness of each of the dielectric layers extracted from an image obtained by scanning a cross section of the body 110 in the length and thickness direction (LT) with a scanning electron microscope (SEM), and measuring the average thickness of each of the dielectric layers extracted from the image obtained by scanning a cross section of the body 110 in the length and thickness direction (LT) with a scanning electron microscope (SEM). The average thickness td of the dielectric layer 111 may be calculated by measuring the thickness of each of the dielectric layers extracted from the image obtained by scanning a cross section of the body 110 in the length and thickness direction (LT) with a scanning electron microscope (SEM), and measuring the average thickness of each of the dielectric layers extracted from the image obtained by scanning a cross section of the body 110 in the length and thickness direction (LT).

[0031] As shown in FIG. 2, the internal electrodes 121 and 122 are alternately arranged with the dielectric layer 111 interposed therebetween.

[0032] The internal electrodes 121, 122 may include first and second internal electrodes 121, 122. The first and second internal electrodes 121, 122 are alternately arranged to face each other with the dielectric layer 111 constituting the body 110 interposed therebetween, and may be exposed to third and fourth surfaces 3, 4 of the body 110, respectively.

[0033] Referring to FIG. 2, the first internal electrode 121 may be spaced apart from the fourth surface 4 and exposed through the third surface 3, and the second internal electrode 122 may be spaced apart from the third surface 3 and exposed through the fourth surface 4.

[0034] At this time, the first and second internal electrodes 121 and 122 may be electrically isolated from each other by the dielectric layer 111 disposed therebetween.

[0035] Referring to FIG. 4, the body 110 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, and then firing the stacked ceramic green sheets.

[0036] There are no particular limitations on the material forming the internal electrodes 121 and 122, and any material having excellent electrical conductivity can be used. For example, the internal electrodes 121 and 122 can be formed by printing a conductive paste for internal electrodes containing 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 on a ceramic green sheet.

[0037] The method for printing the conductive paste for the internal electrodes may be a screen printing method, a gravure printing method, or the like, but the present invention is not limited thereto.

[0038] The average thickness te of the internal electrodes 121, 122 is not particularly limited and may vary depending on the purpose. In order to miniaturize the multilayer electronic component 100, the average thickness te of the internal electrodes 121, 122 may be 0.35 μm or less, and in order to improve the reliability of the multilayer electronic component 100 under high temperature and high pressure, the average thickness te of the internal electrodes 121, 122 may be 3 μm or more.

[0039] The average thickness te of the internal electrodes 121 and 122 may be calculated by measuring the thickness of each of the internal electrode layers extracted from an image obtained by scanning a cross section of the body 110 in the length and thickness direction (LT) cut at the center of the width direction using a scanning electron microscope (SEM), and measuring the average thickness of each of the internal electrodes 121 and 122. The average thickness te of the internal electrodes 121 and 122 may be calculated by measuring the thickness of each of the internal electrode layers extracted from an image obtained by scanning a cross section of the body 110 in the length and thickness direction (LT) cut at the center of the width direction using a scanning electron microscope (SEM), and measuring the average thickness of each of the internal electrode layers extracted from the image obtained by scanning a cross section of the body 110 in the length and thickness ...

[0040] On the other hand, in order to improve the reliability of the multilayer electronic component 100 in a high-temperature and high-pressure environment, td>te×2 can be satisfied, where td is the average thickness of the dielectric layers and te is the average thickness of the internal electrodes.

[0041] The body 110 may include a capacitance forming portion Ac which is a region in which the dielectric layer 111 and the internal electrodes 121, 122 are arranged to overlap in the first direction.

[0042] The capacitance forming portion Ac is a portion that contributes to forming the capacitance of the capacitor, and may be formed by repeatedly laminating a plurality of first and second internal electrodes 121, 122 with the dielectric layer 111 interposed therebetween.

[0043] 2 and 3, cover portions 112 and 113 may be disposed on one and the other surfaces of the capacitance forming portion Ac in the first direction.

[0044] The covers 112 and 113 can serve to prevent damage to the internal electrodes due to physical or chemical stress, and can also serve to improve the strength of the multilayer electronic component 100 .

[0045] The cover portions 112, 113 do not include internal electrodes and may include the same material as the dielectric layer 111, and may be formed by stacking a single dielectric layer or two or more dielectric layers in the thickness direction on the upper and lower surfaces of the capacitance forming portion Ac, respectively.

[0046] The specific shapes of the cover portions 112 and 113 will be described later.

[0047] Referring to FIG. 3, margin portions 114 and 115 may be disposed on one and the other surfaces of the capacitance forming portion Ac in the third direction.

[0048] The margin portions 114, 115 include a margin portion 114 disposed on the sixth surface 6 of the body 110 and a margin portion 115 disposed on the fifth surface 5. That is, the margin portions 114, 115 may be disposed on both side surfaces of the ceramic body 110 in the width direction.

[0049] The margin portions 114, 115 may refer to the regions between both ends of the first and second internal electrodes 121, 122 and the boundary surface of the body 110 in a cross section of the body 110 cut in the width-thickness (WT) direction, as shown in FIG. 3.

[0050] The margins 114 and 115 essentially serve to prevent damage to the internal electrodes due to physical or chemical stress.

[0051] The margin portions 114 and 115 may be formed by applying a conductive paste to the ceramic green sheet except for the areas where the margin portions are to be formed, to form internal electrodes.

[0052] In addition, in order to suppress steps caused by the internal electrodes 121, 122, the laminated internal electrodes can be cut so as to be exposed on the fifth and sixth faces 5, 6 of the main body, and then a single dielectric layer or two or more dielectric layers can be laminated in the width direction on both side faces of the capacitance forming portion Ac to form margin portions 114, 115.

[0053] On the other hand, there is no need to particularly limit the width of the marginal portions 114, 115. However, in order to more easily achieve a smaller size and higher capacity of the multilayer electronic component, the average width of the marginal portions 114, 115 can be 15 μm or less.

[0054] The average width of the margin portions 114, 115 may mean the average size of the margin portions 114, 115 in the third direction, and may be the average value of the sizes of the margin portions 114, 115 in the third direction measured at five equally spaced points on the side of the capacitance forming portion Ac.

[0055] 1 and 2, external electrodes 130 and 140 are disposed on a body 110 .

[0056] The outer electrodes 130 and 140 are disposed on the body 110 and are connected to the inner electrodes 121 and 122 .

[0057] As shown in FIG. 2, the first and second external electrodes 130 and 140 may be disposed on third and fourth surfaces 3 and 4 of the body 110, respectively, and connected to the first and second internal electrodes 121 and 122, respectively.

[0058] In this embodiment, a structure in which the multilayer electronic component 100 has two external electrodes 130, 140 is described, but the number and shapes of the external electrodes 130, 140 can be changed depending on the configuration of the internal electrodes 121, 122 and other purposes.

[0059] Meanwhile, the external electrodes 130 and 140 may be formed using any material having electrical conductivity, such as a metal, and the specific material may be determined in consideration of electrical characteristics, structural stability, etc., and may further have a multi-layer structure.

[0060] For example, the external electrodes 130, 140 may include an electrode layer disposed on the body 110 and a plating layer formed on the electrode layer.

[0061] More specifically, the electrode layer may be a fired electrode containing a conductive metal and glass, or a resin-based electrode containing a conductive metal and resin.

[0062] Also, the electrode layer may be in a form in which a fired electrode and a resin-based electrode are sequentially formed on the body 110. Also, the electrode layer may be formed by transferring a sheet including a conductive metal onto the body 110, or by transferring a sheet including a conductive metal onto the fired electrode.

[0063] The conductive metal contained in the electrode layer may be any material having excellent electrical conductivity, and is not particularly limited. For example, the conductive metal may be 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.

[0064] The plating layer may be a plating layer containing one or more of nickel (Ni), tin (Sn), palladium (Pd) and alloys thereof, and may be formed of a plurality of layers.

[0065] More specifically, the plating layer may be a Ni plating layer or a Sn plating layer, and may be a form in which a Ni plating layer and a Sn plating layer are sequentially formed on an electrode layer, or a form in which a Sn plating layer, a Ni plating layer, and a Sn plating layer are sequentially formed. Also, the plating layer may include a plurality of Ni plating layers and / or a plurality of Sn plating layers.

[0066] The size of the multilayer electronic component 100 does not need to be particularly limited.

[0067] In order to simultaneously achieve miniaturization and high capacity, the multilayer electronic component 100 may have a size of 0201 (length x width, 0.2 mm x 0.1 mm) or less, and in the case of a product in which reliability in a high temperature and high pressure environment is important, the multilayer electronic component 100 may have a size of 3216 (length x width, 3.2 mm x 1.6 mm) or more, but is not limited to this.

[0068] Here, the length of the multilayer electronic component 100 may refer to the maximum size of the multilayer electronic component 100 in a second direction, and the width of the multilayer electronic component 100 may refer to the maximum size of the multilayer electronic component in a third direction.

[0069] FIG. 5 is a schematic diagram showing the clearance and creepage distance between a conductive material and an insulating material.

[0070] Referring to Fig. 5, conductive materials are disposed on insulating materials. Here, the conductive materials may refer to external electrodes of a multilayer electronic component, and the insulating materials may refer to a cover part. The distance indicated by R refers to clearance, which is the shortest distance across the space between conductive materials, and the distance indicated by D refers to creepage distance, which is the shortest distance along the surface of the insulating material between conductive materials.

[0071] In the present invention, the creepage distance is increased to increase the distance over which charges can travel, thereby suppressing the arc discharge phenomenon and improving the reliability of the multilayer electronic component 100.

[0072] The surface shape of the cover parts 112 and 113 for increasing the creepage distance will be described in detail below.

[0073] Meanwhile, in the following, of the cover parts 112 and 113, the description will be based on the cover part 112 arranged on one side of the capacitance forming part in the first direction, but the shape of the surface of the cover part can be similarly applied to the cover part 113 arranged on the other side of the capacitance forming part in the first direction.

[0074] Conventionally, the surface of the cover of a multilayer electronic component may have a flat shape, a number of holes, or a shape with a roughness in which concaves and conves are repeated. If the surface of the cover is flat, it is difficult to increase the creepage distance, and even if the surface of the cover has a number of holes or a roughness, hopping conduction may occur due to insufficient discontinuity at the holes or roughness when high voltage is applied to the multilayer electronic component, and therefore the effect of suppressing the phenomenon of arc discharge under high voltage may be insufficient. That is, even if the surface of the cover has a number of holes or a roughness, sufficient discontinuity may not be provided to increase the creepage distance.

[0075] Therefore, in one embodiment of the present invention, sufficient discontinuity is provided on the surface of the cover part to increase the creepage distance, thereby suppressing the arc discharge phenomenon that may occur in a multilayer electronic component in a high-voltage environment.

[0076] 6, the surface of the cover 112 according to an embodiment of the present invention may include a flat portion 11 forming a first surface and a second surface, a protruding portion 12 protruding in a first direction from the first surface or the second surface, and a groove portion 13 recessed in the first direction from the first surface or the second surface. In this case, one end of the protruding portion 12 may be disposed on the groove portion 13 while being spaced apart from the groove portion 13.

[0077] The flat portion 11 may refer to a region having a flat shape among the outermost surface of the cover portion 112, and may refer to a region forming the first surface 1 or second surface 2 of the main body 110.

[0078] On the other hand, the flat portion 11 may be curved due to shrinkage during the manufacturing process. Even in this case, the protrusions 12 correspond to the areas disposed above the grooves 13, and therefore can be distinguished from the flat portion 11.

[0079] The protrusion 12 may have a shape protruding in a first direction from the first surface or the second surface, and the groove 13 may have a concave shape in the first direction from the first surface or the second surface. The groove 13 may refer to a region where a part of the dielectric layers L1, L2, and L3 of the cover 112 is missing, and the protrusion 12 may refer to a region where the part of the dielectric layers L1, L2, and L3 is missing and protrudes in the first direction.

[0080] At this time, one end of the protrusion 12 may be disposed apart from the groove 13, and one end of the protrusion 12 may be disposed on the groove 13. With this structure, discontinuity may be imparted to the surface of the cover 112 to such an extent that the creepage distance along the surface of the cover 112 is sufficiently increased, and thus, even when a high voltage is applied to the multilayer electronic component 100, the occurrence of an arc discharge phenomenon may be suppressed.

[0081] Meanwhile, the above-mentioned surface structure of the cover portion 112 can be similarly applied to the cover portion 113. However, in one embodiment, the number of protrusions 12 arranged on the surface of the cover portion 112 arranged on one side in the first direction of the capacitance forming portion Ac may be different from the number of protrusions 12 arranged on the surface of the cover portion arranged on the other side in the first direction of the capacitance forming portion Ac.

[0082] Meanwhile, as described above, the cover portion 112 can be formed by laminating a single dielectric layer or two or more dielectric layers in the thickness direction (first direction) on the upper and lower surfaces of the capacitance forming portion Ac, respectively, so that the cover portion 112 can include one or more dielectric layers L1, L2, L3. In Fig. 6, the dielectric layers of the cover portion are represented by L1, L2, L3 to distinguish them from the dielectric layer 111 included in the capacitance forming portion Ac.

[0083] Meanwhile, in one embodiment, a notch 14 may be disposed between one end of the protrusion 12 and the flat portion 11 not connected to the protrusion 12. As a result, a part of the dielectric layer constituting the cover part 112 may have a discontinuous shape when viewed from the cross section in the first direction and the second direction, and thus the creepage distance along the surface of the cover part 112 may be further increased, and the arc discharge suppression effect may be more prominent.

[0084] Meanwhile, in one embodiment, the surface of the cover part adjacent to the cut part 14 may have a step shape. One example of forming such a structure is a case where the protrusion 12 is formed by peeling off a part of the dielectric layers L1, L2, and L3 constituting the cover part 112, but is not limited thereto.

[0085] Meanwhile, as in one embodiment of the present invention, the surface of the cover part 112 may include a flat part 11 forming a first surface and a second surface, a protruding part 12 protruding in a first direction from the first surface or the second surface, and a groove part 13 recessed in the first direction from the first surface or the second surface. In this case, one end of the protruding part 12 is spaced apart from the groove part 13 and disposed on the groove part 13. If the protruding part 12 and the groove part 13 are formed too large in the first direction, the effective thickness of the cover part 112 may be significantly reduced, which may degrade the reliability of the multilayer electronic component 100.

[0086] Specifically, when the average size in the first direction from the end in the first direction of the internal electrode 121 arranged at the outermost side in the first direction of the capacitance forming portion to the flat portion 11 is T1 and the average size in the first direction from the lowest point in the first direction of the groove portion 13 to the flat portion 11 is T2, if T2 / T1 exceeds 0.20, the thickness of the cover portion excluding the protrusion portion 12 is significantly reduced, which may reduce the moisture resistance reliability of the multilayer electronic component 100. Therefore, it is preferable that T2 / T1 is 0.20 or less.

[0087] On the other hand, if T2 / T1 is less than 0.01, sufficient discontinuity cannot be imparted to the surface of the cover portion 112, and the phenomenon of suppressing arc discharge in the multilayer electronic component 100 may not be sufficient. Therefore, it is preferable that T2 / T1 is 0.01 or more.

[0088] That is, in one embodiment, by making T2 / T1 satisfy the range of 0.01 to 0.20, it is possible to suppress the arc discharge phenomenon in the multilayer electronic component 100 and at the same time suppress the deterioration of the moisture resistance reliability.

[0089] In one embodiment, when the average size in the first direction from the end in the first direction of the internal electrode 121 arranged at the outermost side in the first direction of the capacitance forming portion to the flat portion 11 is T1, T1 can be greater than or equal to 150 μm and less than or equal to 500 μm, but is not limited thereto.

[0090] FIG. 7 is a schematic diagram showing a modification of FIG.

[0091] 7, the protrusion 12 according to the modified example may include one or more dielectric layers L1, L2. Therefore, the groove 13 may refer to an area where one or more dielectric layers L1, L2 are missing.

[0092] In the case of the modified example having a structure in which the protrusion 12 includes one or more dielectric layers L1, L2, the creepage distance along the surface of the cover 112 can be further increased, and the arc discharge suppression effect can be further increased. As a result, the arc discharge suppression effect of the multilayer electronic component 100 can be further increased.

[0093] FIG. 8 is a schematic diagram showing a modification of FIG.

[0094] 8, the protrusion 12 according to the modified example may be staggered. The staggered shape of the protrusion 12 may be a shape including a plurality of recesses and protrusions. The recesses and protrusions may be arranged alternately, but are not limited thereto, and the protrusion 12 may be a shape in which the recesses and protrusions are irregularly arranged.

[0095] According to the modified example, when the protrusions 12 are staggered, the creepage distance along the surface of the cover part 112 can be further increased, and the arc discharge suppression effect can be further increased. As a result, the arc discharge suppression effect of the multilayer electronic component 100 can be further increased.

[0096] The surface structure of the cover parts 112, 113 described above can be similarly applied to the surfaces of the margin parts 114, 115. Specifically, in one embodiment, the surfaces of the margin parts 114, 115 can include a flat part forming the fifth surface and the sixth surface 5, 6, a protruding part protruding in the third direction from the fifth surface or the sixth surface, and a groove part recessed in the third direction from the fifth surface or the sixth surface. When the margin parts 114, 115 have such a surface structure, the arc discharge phenomenon can be suppressed even when an external electrode is formed to cover a part of the margin part.

[0097] (Experimental Example) Table 1 shows the results of arc discharge evaluation and moisture resistance reliability evaluation conducted on samples of multilayer electronic components manufactured with different T2 / T1.

[0098] The electronic component sample was made by adding other sub-components to the main component powder of CSZT-based base material, mixing it with a dispersant using ethanol and toluene as solvents, and then mixing it with a binder to produce a ceramic sheet. Ni electrodes were printed on the molded ceramic sheet, stacked, and pressed, and the cut chips were calcined to remove the binder, and then fired in a reducing atmosphere. After that, a termination process was performed with copper (Cu) paste and the electrodes were fired, completing the multilayer electronic component 100.

[0099] Meanwhile, the strength of the surface of the cover part varies depending on the degree of polymerization of the binder added to the ceramic sheet. When wet grinding is performed on cover parts having different strengths, the manner in which a part of the cover part is peeled off also varies, and thus the value of T2 / T1 can be adjusted. In this experimental example, the value of T2 / T1 was adjusted by varying the degree of polymerization of the binder added to the ceramic sheet forming the cover part and performing wet grinding, but the present invention is not limited thereto, and various methods for adjusting the peeling of the surface of the cover part can be used.

[0100] Arc discharge evaluation was performed using a Chroma HIPOT Tester under conditions of applying a DC voltage of 0 to 5 kV and a ramp input for 12.5 seconds. If a breakdown occurred at a voltage lower than the normal BDV without any arc discharge phenomenon, the device was judged to be NG.

[0101] In the case of moisture resistance reliability evaluation, samples in which the insulation resistance value decreased to 10% or less of the initial value under the conditions of humidity 85%, temperature 85°C, voltage 630V, and time 48 hours were judged as NG.

[0102] Meanwhile, the arc discharge evaluation was performed on 10 samples, and the moisture resistance reliability evaluation was performed on 320 samples, and the T2 / T1 value was the average value measured for 10 arbitrary samples at the rot of the multilayer electronic components manufactured with different degrees of polymerization of the binder added to the ceramic sheet. Meanwhile, the case of Example 1 corresponds to a multilayer electronic component of 3216 size with a rated voltage of 630V, and the case of Example 2 corresponds to a multilayer electronic component of 3225 size with a rated voltage of 630V.

[0103] The T2 / T1 value was determined by mounting the multilayer electronic components in the length-thickness direction to manufacture a mold, polishing it to the center in the width direction, and measuring the T1 and T2 values ​​with a scanning electron microscope (SEM) to confirm the ratio. At this time, the T1 and T2 values ​​were calculated by averaging the values ​​measured at three or more equally spaced points in the length direction.

[0104] [Table 1]

[0105] Referring to Table 1, it can be seen that in both Example 1 and Example 2, when T2 / T1 is 0.01 or more and 0.2 or less, the NG ratios are all 0% in the arc discharge evaluation and moisture resistance reliability evaluation. It can also be seen that when T2 / T1 is less than 0.01, a short circuit occurs due to arc discharge, and when T2 / T1 exceeds 0.2, the moisture resistance reliability decreases.

[0106] Therefore, regardless of the size of the multilayer electronic component, when T2 / T1 is 0.01 or more and 0.2 or less, short circuits due to arc discharge can be prevented and at the same time, moisture resistance reliability can be improved.

[0107] Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments and the accompanying drawings, but is limited by the scope of the accompanying claims. Therefore, various substitutions, modifications, and changes can be made by a person having ordinary knowledge in the art within the scope of the technical idea of ​​the present invention described in the claims, and these also belong to the scope of the present invention.

[0108] In addition, the expression "one embodiment" used in the present disclosure does not mean the same embodiment, but is provided to emphasize and describe each unique feature that is different from the others. However, the above-mentioned embodiment does not exclude being realized in combination with the features of another embodiment. For example, even if a matter described in a specific embodiment is not described in another embodiment, it can be understood as a description related to the other embodiment, unless there is a description that is opposite or contradictory to the matter in the other embodiment.

[0109] The terms used in the present disclosure are merely used to describe one embodiment and are not intended to limit the present disclosure. In this case, the singular expression includes the plural expression unless the context clearly indicates otherwise. [Explanation of symbols]

[0110] 100 Multilayer electronic components 110 Main unit 111 Dielectric layer 112, 113 Cover part 114, 115 Margin 121, 122 Internal electrode 130, 140 external electrode 11 Flat area 12 Protrusion 13 Groove 14 Cutting part

Claims

1. a body including a dielectric layer and internal electrodes alternately disposed in a first direction with the dielectric layer sandwiched therebetween, the body including first and second surfaces facing each other in the first direction, third and fourth surfaces connected to the first and second surfaces and facing each other in the second direction, and fifth and sixth surfaces connected from the first surface to the fourth surface and facing each other in the third direction; and external electrodes disposed on the third surface and the fourth surface, the main body includes a capacitance forming portion in which the dielectric layer and the internal electrodes are arranged to overlap in the first direction, and a cover portion arranged on one surface and the other surface of the capacitance forming portion in the first direction, a surface of the cover portion includes a flat portion forming the first surface and the second surface, a protruding portion protruding from the first surface or the second surface in the first direction, and a groove portion recessed from the first surface or the second surface in the first direction, one end of the protrusion is disposed above the groove and spaced apart from the groove.

2. When an average size in the first direction from an end portion in the first direction of the internal electrode arranged at the outermost side in the first direction of the capacitance forming portion to the flat portion is T1, and an average size in the first direction from a lowest point in the first direction of the groove portion to the flat portion is T2, 2. The multilayer electronic component according to claim 1, wherein T2 / T1 is equal to or greater than 0.01 and equal to or less than 0.

20.

3. The multilayer electronic component according to claim 1 , wherein a notch is disposed between one end of said protruding portion and said flat portion.

4. 4. The multilayer electronic component according to claim 3, wherein a surface of said cover portion adjacent to said cut portion is stepped.

5. The laminated electronic component according to claim 1 , wherein the protrusion comprises one or more dielectric layers.

6. The multilayer electronic component according to claim 1 , wherein the protrusions are arranged in a staggered pattern.

7. 2. The multilayer electronic component according to claim 1, wherein a number of the protrusions arranged on a surface of the cover portion arranged on one side of the capacitance forming portion in the first direction is different from a number of the protrusions arranged on a surface of the cover portion arranged on the other side of the capacitance forming portion in the first direction.

8. 2. The multilayer electronic component according to claim 1, wherein the main body further includes margin portions arranged on one surface and the other surface of the capacitance forming portion in the third direction, and surfaces of the margin portions include flat portions forming the fifth surface and the sixth surface, a protrusion protruding from the fifth surface or the sixth surface in the third direction, and a groove portion recessed from the fifth surface or the sixth surface in the third direction.

9. 2. The multilayer electronic component according to claim 1, wherein when an average size in the first direction from an end in the first direction of the internal electrode arranged at the outermost side in the capacitance forming portion to the flat portion is defined as T1, T1 satisfies 150 μm or more and 500 μm or less.

10. 2. The multilayer electronic component according to claim 1, wherein the average thickness of the dielectric layers is td, and td is 3 μm or more.

11. 2. The multilayer electronic component according to claim 1, wherein td>te×2 is satisfied, where td is an average thickness of said dielectric layers and te is an average thickness of said internal electrodes.

12. 2. The laminated electronic component according to claim 1, wherein the dielectric layer contains calcium (Ca), strontium (Sr), zirconium (Zr) and titanium (Ti).

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