Multilayer electronic component

Abstract

To provide a multilayer electronic component having excellent reliability, improved mounting reliability, and reduced breakage of a body.SOLUTION: In a multilayer electronic component, corners of a body have a rounded shape, and a radius of curvature Ru of a corner positioned in an upper cover portion 112 is larger than a radius of curvature of a corner positioned in a lower cover portion. An average size of dielectric crystal grains included in an upper cover portion is larger than an average size of dielectric crystal grains included in a lower cover portion.SELECTED DRAWING: Figure 4

Description

Technical Field

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

Background Art

[0002] A multilayer ceramic capacitor (MLCC), which is one of multilayer electronic components, is a chip-shaped capacitor mounted on a printed circuit board of various electronic products such as video devices like liquid crystal display (LCD) and plasma display panel (PDP), computers, smartphones, and mobile phones, and serves to charge or discharge electricity.

[0003] Due to the advantages of being small in size while ensuring high capacitance and easy to mount, multilayer ceramic capacitors can be used as components of various electronic devices. As various electronic devices such as computers and mobile devices are miniaturized and have increased output, the requirements for miniaturization and high capacitance of multilayer ceramic capacitors are increasing.

[0004] In addition, as the application to automotive electrical components and the like increases, high reliability in various environments is required.

[0005] Multilayer ceramic capacitors are generally mounted on a substrate and used. Therefore, mounting reliability is one of the very important factors in multilayer ceramic capacitor products. To ensure mounting reliability, the mounting strength must be improved.

[0006] Also, cracking of the body of the multilayer ceramic capacitor may cause various reliability degradations such as a decrease in moisture resistance reliability and a decrease in insulation resistance.

Summary of the Invention

Problems to be Solved by the Invention

[0007] One of the various objects of the present invention is to provide a laminated electronic component with excellent reliability.

[0008] One of the various objects of the present invention is to provide a laminated electronic component with improved mounting reliability.

[0009] One of the various objects of the present invention is to provide a laminated electronic component in which cracking of the main body is suppressed.

[0010] However, the object of the present invention is not limited to the above-described content, and can be more easily understood in the process of explaining the specific embodiments of the present invention.

Means for Solving the Problems

[0011] The laminated electronic component according to an embodiment of the present invention includes a capacitance forming portion including a dielectric layer and first and second internal electrodes alternately arranged in a first direction with the dielectric layer interposed therebetween, a first cover portion disposed above the capacitance forming portion in the first direction, and a second cover portion disposed below the capacitance forming portion in the first direction. The laminated electronic component includes a 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 a second direction, and fifth and sixth surfaces connected to the first to fourth surfaces and facing each other in a third direction, and first and second external electrodes disposed on the main body and connected to the first and second internal electrodes, respectively. In a cross section of the main body in the first and second directions, the corners of the main body have a round shape. When the radius of curvature of the corner located in the first cover portion is Ru and the radius of curvature of the corner located in the second cover portion is Rd, Rd < Ru is satisfied. When the average size of the dielectric crystal grains included in the first cover portion is Gs1 and the average size of the dielectric crystal grains included in the second cover portion is Gs2, Gs2 < Gs1 can be satisfied.

Effects of the Invention

[0012] As one of the various effects of the present invention, the reliability of the laminated electronic component can be improved.

[0013] As one of the various effects of the present invention, the mounting reliability of the multilayer electronic component can be improved.

[0014] As one of the various effects of the present invention, cracking of the main body of the multilayer electronic component can be suppressed.

[0015] However, the diverse and significant advantages and effects of the present invention are not limited to the above-described content, and can be more easily understood in the process of describing the specific embodiments of the present invention.

Brief Description of the Drawings

[0016]

Figure 1

Figure 2

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Figure 10

Mode for Carrying Out the Invention

[0017] Hereinafter, embodiments of the present invention will be described with reference to specific embodiments and the accompanying drawings. However, the embodiments of the present invention can be modified into various other forms, and the scope of the present invention is not limited to the embodiments described below. Also, the embodiments of the present invention are provided to more fully explain the present invention to those of ordinary skill in the art. Therefore, elements such as the shape and size in the drawings may be enlarged or reduced (or emphasized or simplified) for a clearer explanation, and elements denoted by the same reference numerals in the drawings are the same elements.

[0018] In addition, parts not related to the explanation are omitted in the drawings for clearly explaining the present invention, and the sizes and thicknesses of the illustrated components are arbitrarily shown for the convenience of explanation, so the present invention is not necessarily limited by the illustration. Also, components with the same functions within the scope of the same idea are described using the same reference numerals. Furthermore, throughout the specification, when a certain part "includes" a certain component, it means that other components can be further included, rather than excluding other components, unless otherwise stated to the contrary.

[0019] In the drawings, the first direction can be defined as the stacking direction or the thickness (T) direction, the second direction as the length (L) direction, and the third direction as the width (W) direction.

[0020] Multilayer electronic component FIG. 1 schematically shows a perspective view of a stacked electronic component according to an embodiment of the present invention, FIG. 2 schematically shows a cross-sectional view taken along line I-I' of FIG. 1, FIG. 3 schematically shows a cross-sectional view taken along line II-II' of FIG. 1, FIG. 4 is an enlarged view of the K1 region in FIG. 2, FIG. 5 is an enlarged view of the K2 region in FIG. 2, FIG. 6 is an enlarged view of the K3 region in FIG. 2, FIG. 7 is an enlarged view of the K4 region in FIG. 2, FIG. 8 is an enlarged view of the K5 region in FIG. 2, FIG. 9 is an enlarged view of the K6 region in FIG. 3, and FIG. 10 is an enlarged view of the K7 region in FIG. 3.

[0021] Hereinafter, with reference to FIGS. 1 to 10, a multilayer electronic component 100 according to an embodiment of the present invention will be described in detail. Further, as an example of the multilayer electronic component, a multilayer ceramic capacitor (hereinafter referred to as "MLCC") will be described, but the present invention is not limited thereto, and it can also be applied to various multilayer electronic components using a ceramic material, such as an inductor, a piezoelectric element, a varistor, or a thermistor.

[0022] The multilayer electronic component 100 according to an embodiment of the present invention includes a capacitance forming portion Ac including a dielectric layer 111 and first and second internal electrodes 121 and 122 alternately arranged in a first direction with the dielectric layer interposed therebetween, a first cover portion 112 disposed above the capacitance forming portion in the first direction, and a second cover portion 113 disposed below the capacitance forming portion in the first direction. The multilayer electronic component 100 includes a main body 110 including first and second surfaces 1 and 2 facing each other in the first direction, third and fourth surfaces 3 and 4 connected to the first and second surfaces and facing each other in a second direction, and fifth and sixth surfaces 5 and 6 connected to the first to fourth surfaces and facing each other in a third direction, and first and second external electrodes 131 and 132 disposed on the main body and connected to the first and second internal electrodes, respectively. In a cross section of the main body in the first and second directions, the corners of the main body have a round shape. When the radius of curvature of the corner located in the first cover portion is Ru and the radius of curvature of the corner located in the second cover portion is Rd, Rd < Ru is satisfied. When the average size of the dielectric crystal grains included in the first cover portion is Gs1 and the average size of the dielectric crystal grains included in the second cover portion is Gs2, Gs2 < Gs1 can be satisfied.

[0023] According to an embodiment of the present invention, by making the corners of the main body 110 have a round shape, the radius of curvature Ru of the corner located in the first cover portion 112 be larger than the radius of curvature Rd of the corner located in the second cover portion 113, and the average size Gs1 of the dielectric crystal grains included in the first cover portion 112 be larger than the average size Gs2 of the dielectric crystal grains included in the second cover portion 113, the mounting reliability can be improved and cracking of the main body can be suppressed.

[0024] Hereinafter, each component included in the multilayer electronic component 100 according to an embodiment of the present invention will be described.

[0025] The main body 110 can have a dielectric layer 111 and internal electrodes 121 and 122 alternately laminated.

[0026] There is no particular limitation on the specific shape of the main body 110. As shown in the figure, the main body 110 can have a hexahedral shape or a shape similar thereto. Due to the shrinkage of the ceramic powder contained in the main body 110 during the firing process, the main body 110 may not have a perfect hexahedral shape with straight lines. Alternatively, by separately performing a process on the corners connecting the respective faces of the main body 110 and rounding them, the corners connecting the first face and the third to sixth faces and / or the corners connecting the second face and the third to sixth faces can have a rounded form.

[0027] The main body 110 can have a first and a second face 1, 2 facing each other in a first direction, a third and a fourth face 3, 4 connected to the first and second faces 1, 2 and facing each other in a second direction, and a fifth and a sixth face 5, 6 connected to the first and second faces 1, 2 and the third and fourth faces 3, 4 and facing each other in a third direction. The first face 1 can be a mounting face arranged to face the substrate when mounted on the substrate.

[0028] The plurality of dielectric layers 111 forming the main body 110 are in a fired state, and the boundary between adjacent dielectric layers 111 can be integrated to the extent that it is difficult to confirm without using a scanning electron microscope (SEM). The number of laminated dielectric layers does not need to be particularly limited and can be determined in consideration of the size of the multilayer electronic component. For example, the main body can be formed by laminating 400 or more dielectric layers.

[0029] The dielectric layer 111 can be formed by manufacturing a ceramic slurry containing ceramic powder, an organic solvent, and a binder, applying and drying the slurry on a carrier film to provide a ceramic green sheet, and then firing the ceramic green sheet. The ceramic powder is not particularly limited as long as sufficient capacitance can be obtained. For example, barium titanate (BaTiO3)-based powder, normal dielectric powder of a CaZrO3 substrate, etc. can be used as the ceramic powder. More specifically, as the barium titanate (BaTiO3)-based powder, BaTiO3, (Ba 1-x Ca x )TiO3 (0 < x < 1), Ba(Ti 1-y Ca y )O3 (0 < y < 1), (Ba 1-x Ca x )(Ti 1-y Zr y )O3 (0 < x < 1, 0 < y < 1), and Ba(Ti 1-y Zr y )O3 (0 < y < 1) can be one or more of them, and the normal dielectric powder of the CaZrO3 substrate can be (Ca 1-x Sr x )(Zr 1-y Ti y )O3 (0 < x < 1, 0 < y < 1).

[0030] Therefore, the dielectric layer 111 can contain one or more of BaTiO3, (Ba 1-x Ca x )TiO3 (0 < x < 1), Ba(Ti 1-y Ca y )O3 (0 < y < 1), (Ba 1-x Ca x )(Ti 1-y Zr y )O3 (0 < x < 1, 0 < y < 1), Ba(Ti 1-y Zr y )O3 (0 < y < 1), and (Ca 1-x Sr x )(Zr 1-y Ti y )O3 (0 < x < 1, 0 < y < 1).

[0031] The main body 110 includes a capacitance forming portion Ac that is disposed inside the main body 110 and in which a capacitance is formed by including a first internal electrode 121 and a second internal electrode 122 that are disposed opposite to each other with a dielectric layer 111 interposed therebetween, and cover portions 112 and 113 formed on the upper and lower portions of the capacitance forming portion Ac in a first direction.

[0032] Further, the capacitance forming portion Ac is a portion that contributes to the formation of the capacitance of the capacitor, and can be formed by repeatedly laminating a plurality of first and second internal electrodes 121 and 122 with the dielectric layer 111 interposed therebetween.

[0033] The cover portions 112 and 113 can include a first cover portion 112 disposed on the upper portion of the capacitance forming portion Ac in the first direction and a second cover portion 113 disposed on the lower portion of the capacitance forming portion Ac in the first direction. The first cover portion 112 can be referred to as an upper cover portion, and the second cover portion 113 can be referred to as a lower cover portion.

[0034] The first upper cover portion 112 and the second cover portion 113 can be formed by laminating 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, and can basically serve to prevent damage to the internal electrodes due to physical or chemical stress.

[0035] The first cover portion 112 and the second cover portion 113 can not include internal electrodes. Further, the first cover portion 112 and the second cover portion 113 can include the same material as the dielectric layer 111. That is, the first cover portion 112 and the second cover portion 113 can include a ceramic material, for example, a barium titanate (BaTiO3)-based ceramic material.

[0036] Referring to FIGS. 4 and 5, the corners of the main body 110 in the first and second direction cross-sections of the main body 110 have a round shape. When the radius of curvature of the corner located in the first cover portion 112 is Ru and the radius of curvature of the corner located in the second cover portion 113 is Rd, Rd < Ru can be satisfied. By making the radius of curvature Ru of the corner located in the first cover portion 112 larger than the radius of curvature Rd of the corner located in the second cover portion 113, cracking of the main body can be suppressed, and mounting reliability can be improved.

[0037] Since the radius of curvature Rd of the corner located in the second cover portion 113 is small, when mounted on a substrate, the distance between the substrate and the main body can be minimized to improve the mounting strength. Generally, the larger the radius of curvature of the corner of the main body, the thicker the external electrode, and conversely, the smaller the radius of curvature of the corner of the main body, the thinner the external electrode can be. Therefore, since the radius of curvature Rd of the corner located in the second cover portion 113 is small, as the thickness of the first-1 band portion 131b1 becomes thinner, the distance between the substrate and the main body can be minimized when mounted on the substrate to improve the mounting strength.

[0038] However, the larger the radius of curvature of the corner of the main body, the easier it is to suppress cracking of the main body, and conversely, the smaller the radius of curvature of the corner of the main body, the more difficult it is to suppress cracking of the main body. Therefore, when the radius of curvature Rd of the corner located in the second cover portion 113 is small, the mounting strength can be improved, but there is a risk of cracking of the main body. However, according to an embodiment of the present invention, when the average size of the dielectric crystal grains G1 included in the first cover portion 112 is Gs1 and the average size of the dielectric crystal grains G2 included in the second cover portion 113 is Gs2, Gs2 < Gs1 can be satisfied. Thereby, even if the radius of curvature Rd of the corner located in the second cover portion 113 is small, since the density of the second cover portion 113 is high, cracking of the main body can be suppressed. Therefore, according to an embodiment of the present invention, mounting reliability can be ensured while suppressing cracking of the main body.

[0039] Also, when forming the rounded shape of the corners of the main body 110 by a polishing process, as Gs2 < Gs1 is satisfied, since the density of the first cover part 112 is lower than the density of the second cover part 113, even when the same polishing process is applied, the radius of curvature Ru of the corners located in the first cover part 112 can be made larger than the radius of curvature Rd of the corners located in the second cover part 113.

[0040] In one embodiment, Ru and Rd can satisfy 0.70 < Rd / Ru < 1.00. Thereby, it is possible to ensure the mounting reliability while more easily suppressing the cracking of the main body. When Rd / Ru is 0.70 or less, it may be difficult to simultaneously ensure the effect of suppressing the cracking of the main body and the mounting reliability.

[0041] More preferably, Ru and Rd can satisfy 0.70 < Rd / Ru < 0.95, but are not limited thereto.

[0042] On the other hand, it is not necessary to particularly limit the respective numerical values of Ru and Rd, and they can be appropriately selected in consideration of the size of the multilayer electronic component. For example, in the case of a multilayer electronic component of 1005 size (length: 1.00 mm, width: 0.5 mm), Ru can be 15 mm or more and 30 mm or less, and Rd can be 14 mm or more and less than 30 mm.

[0043] In one embodiment, Gs1 and Gs2 can satisfy 0.80 < Gs2 / Gs1 < 1.00. Thereby, it is possible to ensure the mounting reliability while more easily suppressing the cracking of the main body.

[0044] When Gs2 / Gs1 is 0.80 or less, it may be difficult to simultaneously ensure the effect of suppressing the cracking of the main body and the mounting reliability.

[0045] More preferably, Ru and Rd can satisfy 0.80 < Gs2 / Gs1 < 0.95, but are not limited thereto.

[0046] On the one hand, the numerical values of Gs1 and Gs2 do not need to be particularly limited and can be appropriately selected in consideration of the size of the multilayer electronic component. For example, in the case of a multilayer electronic component of 1005 size (length: 1.00 mm, width: 0.5 mm), Gs1 can be 100 nm or more and 500 nm or less, and Gs2 can be 90 nm or more and 450 nm or less.

[0047] On the other hand, the method of making the radius of curvature Ru of the corner located in the first cover part 112 larger than the radius of curvature Rd of the corner located in the second cover part 113, and making the average size Gs1 of the dielectric crystal grains included in the first cover part 112 larger than the average size Gs2 of the dielectric crystal grains included in the second cover part 113 does not need to be particularly limited. For example, the composition of the ceramic green sheet for forming the first cover part 112 and the ceramic green sheet for forming the second cover part 113 can be made different in terms of the binder content, the type of ceramic powder, etc., so that the density of the second cover part 113 can be made higher than the density of the first cover part 112. Also, the first cover part 112 and the second cover part 113 can be formed using ceramic green sheets of the same composition. For example, after laminating one or more ceramic green sheets to form the second cover part 113, a pressing process is performed once before laminating the ceramic green sheet printed with the internal electrode pattern. After that, the ceramic green sheet printed with the internal electrode pattern and the ceramic green sheet for forming the first cover part 112 are laminated, and the pressing process is performed again, so that the second cover part 113 undergoes two pressing processes, and the density can be controlled to be higher than that of the first cover part 112. Due to such a difference in density between the first and second cover parts, even if the same polishing process conditions are applied to the first and second cover parts in the polishing process, the radius of curvature of the round shape located in each of the first and second cover parts can be controlled to be different.

[0048] In one embodiment, when the average thickness of the first cover portion 112 is tc1 and the average thickness of the second cover portion 113 is tc2, tc2 < tc1 can be satisfied. By satisfying tc2 < tc1, Rd < Ru can be easily satisfied.

[0049] At this time, tc1 and tc2 can satisfy 0.50 < tc2 / tc1 < 1.00. When tc2 / tc1 is 0.50 or less, the role of preventing damage to the internal electrodes by the cover portions 112 and 113 becomes insufficient, or the capacitance per unit volume of the multilayer electronic component may decrease.

[0050] On the other hand, the respective numerical values of tc1 and tc2 do not need to be particularly limited and can be appropriately selected in consideration of the size of the multilayer electronic component. For example, in the case of a multilayer electronic component of the 1005 size (length: 1.00 mm, width: 0.5 mm), tc1 can be 20 μm or more and 70 μm or less, and tc2 can be 15 μm or more and 60 μm or less.

[0051] The thicknesses of the cover portions 112 and 113 can each mean the size in the first direction. The average thickness of the first cover portion 112 can be a value obtained by averaging the sizes in the first direction of the first cover portion 112 measured at five equally spaced points above the capacitance forming portion Ac, and the average thickness of the second cover portion 113 can be a value obtained by averaging the sizes in the first direction of the second cover portion 113 measured at five equally spaced points below the capacitance forming portion Ac.

[0052] In one embodiment, the first external electrode 131 is disposed on the third surface 3 and includes a first-1 band portion 131b1 extending to a part of the first surface 1 and a first-2 band portion 131b2 extending to a part of the second surface 2, and the second external electrode 132 is disposed on the fourth surface 4 and includes a second-1 band portion 132b1 extending to a part of the first surface 1 and a second-2 band portion 132b2 extending to a part of the second surface 2.

[0053] At this time, the average thickness of the first first-band portion 131b1 can be thinner than the average thickness of the first second-band portion 131b2, and the average thickness of the second first-band portion 132b1 can be thinner than the average thickness of the second second-band portion 132b2. Thereby, when mounting the stacked electronic component 100 on the substrate, the distance between the substrate and the main body can be minimized to improve the mounting strength.

[0054] Further, in the cross sections of the main body 110 in the first and second directions, when the thickness of the first first-band portion measured at the central point from the extension line E3 of the third surface to the end of the first first-band portion is Tbd, and the thickness of the first second-band portion measured at the central point from the extension line E3 of the third surface to the end of the first second-band portion is Tbu, Tbd < Tbu can be satisfied.

[0055] Referring to FIG. 5, when the distance from the extension line E3 of the third surface to the end of the first first-band portion is Lbd, the thickness of the first first-band portion measured at a point separated from the extension line E3 of the third surface by Lbd / 2 can be defined as Tbd. Further, referring to FIG. 4, when the distance from the extension line E3 of the third surface to the end of the first second-band portion is Lbu, the thickness of the first second-band portion measured at a point separated from the extension line E3 of the third surface by Lbu / 2 can be defined as Tbu. At this time, Tbu and Tbd can be measured in the cross sections in the first and second directions obtained by cutting the main body at the center in the third direction.

[0056] At this time, Tbd and Tbu can satisfy 0.5 < Tdb / Tbu < 1.0. Thereby, it is possible to ensure the mounting reliability while more easily suppressing the cracking of the main body.

[0057] On the other hand, the respective numerical values of Tbd and Tbu do not need to be particularly limited, and can be appropriately selected in consideration of the size of the stacked electronic component. For example, in the case of a 1005-size (length: 1.00 mm, width: 0.5 mm) stacked electronic component, Tbd can be 17 μm or more and 35 μm or less, and Tbu can be 15 μm or more and 30 μm or less.

[0058] Referring to FIGS. 4 to 6, when the thickness of the first external electrode 131 measured by the first internal electrode 121 disposed at the uppermost part in the first direction is Tau, the thickness of the first external electrode 131 measured on the first internal electrode 121 disposed at the lowermost part in the first direction is Tad, and the thickness of the first external electrode measured at the central part of the main body in the first direction is Tac, Tad < Tau < Tac can be satisfied.

[0059] By forming the external electrodes 131 and 132 by dipping them in a conductive paste, the thickness of the external electrodes 131 and 132 at the central part of the main body 110 can be thicker than the thickness of the external electrodes 131 and 132 outside the main body 110, and by satisfying Rd < Ru, Tad < Tau can be satisfied.

[0060] At this time, the band part of the external electrode can be thinner than the thickness of the external electrode outside the main body, and Tbd < Tbu < Tad < Tau < Tac can be satisfied.

[0061] On the other hand, not only the cross-sections of the main body in the first and second directions but also the cross-sections of the main body in the first and third directions can have a rounded shape at the corners of the main body. Referring to FIGS. 9 and 10, when the radius of curvature of the corner located in the first cover part is Ruw and the radius of curvature of the corner located in the second cover part is Rdw in the cross-section of the main body in the first and third directions, Ruw > Rdw can be satisfied.

[0062] Also, referring to FIGS. 2 and 3, although the first internal electrode or the second internal electrode is disposed at the end in the second direction of the main body, the first and second internal electrodes are not disposed at the end in the third direction of the main body. Therefore, due to the step caused by the thickness of the internal electrode, Ru, Rd, Ruw, and Rud can satisfy Ruw > Ru > Rdw > Rd.

[0063] Referring to FIGS. 7 and 8, the first cover part 112 can include a plurality of crystal grains G1 and pores P1, and the second cover part 113 can include a plurality of crystal grains G2 and pores P2.

[0064] When the porosity of the first cover part 112 is Ps1 and the porosity of the second cover part 113 is Ps2, Ps2 < Ps1 can be satisfied. Since the porosity can also greatly affect the density of the first and second cover parts, by satisfying Ps2 < Ps1, the density of the first cover part can be made lower than that of the second cover part, so that it is possible to more easily suppress cracking of the main body while ensuring mounting reliability.

[0065] In one embodiment, Ps1 and Ps2 can satisfy 0.7 ≤ Ps2 / Ps1 < 1.0. When Ps2 / Ps1 is less than 0.7, sufficient strength of the second cover part 113 is not ensured, and the radius of curvature is likely to be similar to that of the first cover part 112 during polishing, and thus it may be difficult to ensure sufficient mounting strength.

[0066] The average grain size and porosity of the first and second cover parts 112 and 113 can be measured by analyzing an image scanned at a magnification of 50k using a ZEISS SEM on a cross-section cut in the first and second directions at the center in the third direction of the main body. At this time, the central portions in the first direction and the central portions in the second direction of the first and second cover parts 112 and 113 can be scanned with the SEM.

[0067] The pellet diameter (Feret diameter) of the crystal grains can be measured for the scanned image using Zootos, which is particle size measurement software, to obtain the average size of each crystal grain G1 and G2. Further, since the dielectric crystal grains G1 and G2 and the pores P1 and P2 have distinct light and dark differences, the area ratio occupied by the pores P1 with respect to the total area (including pores) of the first cover part observed in the SEM scan image and the area ratio occupied by the pores P2 out of the total area (including pores) of the second cover part observed in the SEM scan image are measured using an image analysis program, and the respective porosities can be obtained.

[0068] Also, margin parts 114 and 115 can be arranged on the side surface of the capacitance forming part Ac.

[0069] The margin portions 114 and 115 can include a first margin portion 114 disposed on the fifth surface 5 of the main body 110 and a second margin portion 115 disposed on the sixth surface 6. That is, the margin portions 114 and 115 can be disposed on both end surfaces in the width direction of the ceramic main body 110.

[0070] As shown in FIG. 3, the margin portions 114 and 115 can mean the regions between the interfaces of both ends of the first and second internal electrodes 121 and 122 and the main body 110 in a cross-section obtained by cutting the main body 110 in the width-thickness (W-T) direction.

[0071] The margin portions 114 and 115 can basically serve to prevent damage to the internal electrodes due to physical or chemical stress.

[0072] The margin portions 114 and 115 can be formed by applying a conductive paste to form internal electrodes except where the margin portions are formed on the ceramic green sheet.

[0073] On the other hand, the widths of the margin portions 114 and 115 do not particularly need to be limited. However, in order to more easily achieve miniaturization and high capacitance of the multilayer electronic component, the average width of the margin portions 114 and 115 can be 15 μm or less.

[0074] The average width of the margin portions 114 and 115 can mean the average size in the third direction of the region where the internal electrodes 121 and 122 are separated from the fifth surface and the average size in the third direction of the region where the internal electrodes 121 and 122 are separated from the sixth surface, and can be a value obtained by averaging the sizes in the third direction of the margin portions 114 and 115 measured at five points having equal intervals in the first direction on the side surface of the capacitance forming portion Ac.

[0075] Therefore, in one embodiment, the average sizes in the third direction of the regions where the internal electrodes 121 and 122 are separated from the fifth and sixth surfaces can be 15 μm or less, respectively.

[0076] The internal electrodes 121 and 122 can include the first and second internal electrodes 121 and 122. The first and second internal electrodes 121 and 122 are alternately arranged so as to face each other with the dielectric layer 111 constituting the main body 110 interposed therebetween, and can be respectively exposed on the third and fourth surfaces 3 and 4 of the main body 110.

[0077] The first internal electrode 121 is separated from the fourth surface 4 and exposed through the third surface 3, and the second internal electrode 122 is separated from the third surface 3 and can be exposed through the fourth surface 4. A first external electrode 131 is arranged on the third surface 3 of the main body and connected to the first internal electrode 121, and a second external electrode 132 can be arranged on the fourth surface 4 of the main body and connected to the second internal electrode 122.

[0078] That is, the first internal electrode 121 is not connected to the second external electrode 132 but is connected to the first external electrode 131, and the second internal electrode 122 is not connected to the first external electrode 131 but is connected to the second external electrode 132. Therefore, the first internal electrode 121 can be formed at a certain distance from the fourth surface 4, and the second internal electrode 122 can be formed at a certain distance from the third surface 3. Also, the first and second internal electrodes 121 and 122 can be arranged separated from the fifth and sixth surfaces of the main body 110.

[0079] The conductive metal included in the internal electrodes 121 and 122 can be one or more of Ni, Cu, Pd, Ag, Au, Pt, In, Sn, Al, Ti, and alloys thereof, but the present invention is not limited thereto.

[0080] The average thickness td of the dielectric layer 111 does not necessarily need to be particularly limited, but for example, it can be 0.1 μm to 10 μm. The average thickness te of the internal electrodes 121 and 122 does not necessarily need to be particularly limited, but for example, it can be 0.05 μm to 3.0 μm. Also, the average thickness td of the dielectric layer 111 and the average thickness te of the internal electrodes 121 and 122 can be arbitrarily set according to desired characteristics and applications. For example, in the case of an electronic component for high-voltage electric fields in order to achieve miniaturization and high capacitance, the average thickness td of the dielectric layer 111 can be less than 2.8 μm, and the average thickness te of the internal electrodes 121 and 122 can be less than 1 μm. Also, in the case of an electronic component for small IT in order to achieve miniaturization and high capacitance, the average thickness td of the dielectric layer 111 can be 0.4 μm or less, and the average thickness te of the internal electrodes 121 and 122 can be 0.4 μm or less.

[0081] The average thickness td of the dielectric layer 111 and the average thickness te of the internal electrodes 121 and 122 respectively mean the sizes in the first direction of the dielectric layer 111 and the internal electrodes 121 and 122. The average thickness td of the dielectric layer 111 and the average thickness te of the internal electrodes 121 and 122 can be measured by scanning the cross-sections in the first direction and the second direction of the main body 110 with a scanning electron microscope (SEM) at a magnification of 10,000 times. More specifically, the average thickness td of the dielectric layer 111 can be measured by measuring the thickness at a number of points of one dielectric layer 111, for example, 30 points at equal intervals in the second direction, and calculating the average value. Also, the average thickness te of the internal electrodes 121 and 122 can be measured by measuring the thickness at a number of points of one internal electrode 121 or 122, for example, 30 points at equal intervals in the second direction, and calculating the average value. The above 30 points at equal intervals can be specified in the capacitance forming portion Ac. On the other hand, after performing such average value measurements for 10 dielectric layers 111 and 10 internal electrodes 121 and 122 respectively, and then measuring the average value, the average thickness td of the dielectric layer 111 and the average thickness te of the internal electrodes 121 and 122 can be further generalized.

[0082] The external electrodes 131 and 132 can be arranged on the third surface 3 and the fourth surface 4 of the main body 110.

[0083] The external electrodes 131 and 132 can be disposed on the third and fourth surfaces 3 and 4 of the main body 110, respectively, and include first and second external electrodes 131 and 132 respectively connected to the first and second internal electrodes 121 and 122.

[0084] Referring to FIG. 1, the external electrodes 131 and 132 can be disposed so as to cover both end faces in the second direction of the side margin portions 114 and 115.

[0085] In this embodiment, the structure in which the multilayer electronic component 100 has two external electrodes 131 and 132 is described. However, the number, shape, etc. of the external electrodes 131 and 132 can be changed according to the form of the internal electrodes 121 and 122 and other purposes.

[0086] On the other hand, the external electrodes 131 and 132 can be formed of any material as long as it has electrical conductivity such as metal, and a specific material can be determined in consideration of electrical characteristics, structural stability, etc., and can further have a multilayer structure.

[0087] For example, the external electrodes 131 and 132 can include an electrode layer disposed on the main body 110 and a plating layer formed on the electrode layer.

[0088] To give a more specific example of the electrode layer, the electrode layer can be a fired electrode including a conductive metal and glass, or a resin-based electrode including a conductive metal and a resin.

[0089] Further, the electrode layer can be in a form in which a fired electrode and a resin-based electrode are sequentially formed on the main body. Also, the electrode layer can be formed by a method of transferring a sheet containing a conductive metal onto the main body, or can be formed by a method of transferring a sheet containing a conductive metal onto a fired electrode.

[0090] As the conductive metal contained in the above electrode layer, a material with excellent electrical conductivity can be used, but it is not particularly limited. For example, the conductive metal can be one or more of nickel (Ni), copper (Cu), and their alloys.

[0091] The above plating layer plays a role in improving the mounting characteristics. The type of the above plating layer is not particularly limited, and it can be a plating layer containing one or more of Ni, Sn, Pd, and their alloys, and can be formed of a plurality of layers.

[0092] To give a more specific example of the above plating layer, the above plating layer can be a Ni plating layer or a Sn plating layer, and can be in a form in which a Ni plating layer and a Sn plating layer are sequentially formed on the above electrode layer, or can be in a form in which a Sn plating layer, a Ni plating layer, and a Sn plating layer are sequentially formed. Also, the above plating layer can include a plurality of Ni plating layers and / or a plurality of Sn plating layers.

[0093] The size of the multilayer electronic component 100 does not need to be particularly limited. For example, the length of the multilayer electronic component 100 can be 4.5 mm or less, the thickness of the multilayer electronic component 100 can be 3.2 mm or less, and the width of the multilayer electronic component 100 can be 3.2 mm or less.

[0094] Here, the length of the multilayer electronic component 100 means the maximum size in the second direction of the multilayer electronic component 100, the thickness of the multilayer electronic component 100 means the maximum size in the first direction of the multilayer electronic component 100, and the width of the multilayer electronic component 100 can mean the maximum size in the third direction of the multilayer electronic component 100.

[0095] Although the embodiments of the present invention have been described in detail above, the present invention is not limited by the above-described embodiments and the accompanying drawings, but is limited by the appended claims. Therefore, within the scope not departing from the technical idea of the present invention described in the claims, various forms of substitution, modification, and change are possible by those having ordinary knowledge in the art, and it can be said that these also belong to the scope of the present invention.

[0096] In addition, the expression "one embodiment" used in the present disclosure does not mean the same embodiment, but is provided to emphasize and explain each different unique feature. However, the above-presented one embodiment does not exclude being implemented in combination with the features of other one embodiments. For example, even if a matter described in a specific one embodiment is not described in another one embodiment, it can be understood as an explanation related to the other one embodiment as long as there is no explanation contrary to or conflicting with that matter in the other one embodiment.

[0097] The terms used in the present disclosure are merely used to explain one embodiment and are not intended to limit the present disclosure. At this time, the singular expression includes plural expressions unless the context clearly indicates otherwise.

Description of Reference Numerals

[0098] 100 Multilayer Electronic Component 110 Body 111 Dielectric Layer 112 First Cover Portion 113 Second Cover Portion 114, 115 Margin Portions 121, 122 Internal Electrodes 131, 132 External Electrodes

Claims

1. A capacitor forming section including a dielectric layer, and first and second internal electrodes alternately arranged in a first direction with the dielectric layer therebetween, a first cover section disposed above the capacitor forming section in the first direction, and a second cover section disposed below the capacitor forming section in the first direction, a 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 a second direction, and fifth and sixth surfaces connected to the first to fourth surfaces and facing each other in a third direction, and first and second external electrodes disposed on the main body and respectively connected to the first and second internal electrodes. When the corners of the main body have a round shape in a cross section in the first and second directions of the main body, and the radius of curvature of the corner located in the first cover section is Ru and the radius of curvature of the corner located in the second cover section is Rd, Rd < Ru is satisfied. A multilayer electronic component in which when the average size of the dielectric crystal grains included in the first cover section is Gs1 and the average size of the dielectric crystal grains included in the second cover section is Gs2, Gs2 < Gs1 is satisfied.

2. The multilayer electronic component according to Claim 1, wherein Ru and Rd satisfy 0.70 < Rd / Ru < 1.

00.

3. The multilayer electronic component according to Claim 1, wherein Gs1 and Gs2 satisfy 0.70 < Gs2 / Gs1 < 1.

00.

4. The multilayer electronic component according to Claim 1, wherein when the average thickness of the first cover section is tc1 and the average thickness of the second cover section is tc2, tc2 < tc1 is satisfied.

5. The multilayer electronic component according to Claim 4, wherein tc1 and tc2 satisfy 0.50 < tc2 / tc1 < 1.

00.

6. The first external electrode is disposed on the third surface and includes a first-1 band section extending to a part of the first surface and a first-2 band section extending to a part of the second surface. The second external electrode is disposed on the fourth surface and includes a second-1 band section extending to a part of the first surface and a second-2 band section extending to a part of the second surface. The multilayer electronic component according to Claim 1.

7. The average thickness of the first-1 band section is thinner than the average thickness of the first-2 band section. The average thickness of the second-1 band section is thinner than the average thickness of the second-2 band section. The multilayer electronic component according to Claim 6.

8. In the cross-sections of the main body in the first and second directions, when the thickness of the first-1 band portion measured at the central point from the extension line of the third surface to the end of the first-1 band portion is Tbd, and the thickness of the first-2 band portion measured at the central point from the extension line of the third surface to the end of the first-2 band portion is Tbu, the laminated electronic component according to claim 6, which satisfies Tbd < Tbu.

9. The laminated electronic component according to claim 8, wherein the Tbd and Tbu satisfy 0.5 < Tdb / Tbu < 1.

0.

10. When the thickness of the first external electrode measured on the first internal electrode arranged at the uppermost part in the first direction is Tau, the thickness of the first external electrode measured on the first internal electrode arranged at the lowermost part in the first direction is Tad, and the thickness of the first external electrode measured at the central part in the first direction of the main body is Tac, the laminated electronic component according to claim 1, which satisfies Tad < Tau < Tac.

11. When the thickness of the first external electrode measured on the first internal electrode arranged at the uppermost part in the first direction is Tau, the thickness of the first external electrode measured on the first internal electrode arranged at the lowermost part in the first direction is Tad, and the thickness of the first external electrode measured at the central part in the first direction of the main body is Tac, the laminated electronic component according to claim 8, which satisfies Tbd < Tbu < Tad < Tau < Tac.

12. In the cross-sections of the main body in the first and third directions, the corners of the main body have a round shape. When the radius of curvature of the corner located in the first cover portion is Ruw and the radius of curvature of the corner located in the second cover portion is Rdw, the laminated electronic component according to claim 1, which satisfies Ruw > Rdw.

13. The laminated electronic component according to claim 12, wherein the Ru, Rd, Ruw, and Rud satisfy Ruw > Ru > Rdw > Rd.

14. When the porosity of the first cover portion is Ps1 and the porosity of the second cover portion is Ps2, The laminated electronic component according to claim 1, which satisfies Ps2 < Ps1.

15. The laminated electronic component according to claim 14, wherein the Ps1 and Ps2 satisfy 0.7 ≦ Ps2 / Ps1 < 1.0.

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