Multilayer electronic component

Abstract

To provide a multilayer electronic component having excellent moisture resistance reliability and high temperature reliability.SOLUTION: A multilayer electronic component 100 includes: a body 110 that includes a dielectric layer 111 and internal electrodes 121, 122 alternately disposed with the dielectric layer, and that also includes first and second surfaces opposing each other in a first direction, third and fourth surfaces connected to the first and second surfaces and opposing each other in a second direction, and fifth and sixth surfaces connected to the first to fourth surfaces and opposing each other in a third direction; and external electrodes 130, 140 that include band portions B1, B2 disposed on the first and second surfaces, connection portions A1, A2 disposed on the third and fourth surfaces, and corner portions C1, C2 connecting the band portions and the connection portions and disposed at corners connecting the first and second surfaces and the third and fourth surfaces. The external electrodes include: first external electrode layers 131, 141 connected to the first and second internal electrodes and including first glass; and second external electrode layers 132, 142 disposed on the first external electrode layer of the corner portions and including second glass. The second glass includes Fe, and the first glass does not include Fe.SELECTED DRAWING: Figure 2

Description

Technical Field

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

Background Art

[0002] A multilayer ceramic capacitor (MLCC), which is one type of multilayer electronic component, is a chip-type capacitor that is mounted on printed circuit boards of various electronic products such as video devices like liquid crystal display (LCD) devices and plasma display panel (PDP) panels, 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 being easy to mount, multilayer ceramic capacitors can be used as components in various electronic devices. As various electronic devices such as computers and mobile devices are miniaturized and have increased output power, the requirements for miniaturization and high capacitance of multilayer ceramic capacitors are increasing.

[0004] The sintered electrode mainly used for the base electrode of a multilayer ceramic capacitor may act as the main penetration path for moisture or plating solution from the outside because the thickness of the sintered electrode becomes thinner from the central part of the body towards the corner.

[0005] Therefore, it is necessary to ensure sufficient thickness of the sintered electrode located at the corner of the body.

Summary of the Invention

Problems to be Solved by the Invention

[0006] One of several objects of the present invention is to provide a multilayer electronic component with excellent moisture resistance reliability and high temperature reliability.

[0007] One of several objects of the present invention is to provide a multilayer electronic component in which an increase in equivalent series resistance (ESR) is suppressed.

[0008] However, the object of the present invention is not limited to the above content and can be more easily understood in the process of explaining specific embodiments of the present invention.

Means for Solving the Problems

[0009] A multilayer electronic component according to an embodiment of the present invention includes a dielectric layer, a first internal electrode and a second internal electrode alternately arranged in a first direction with the dielectric layer interposed therebetween, 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 surface, the second surface, the third surface and the fourth surface and facing each other in a third direction, a main body including the same, a band portion disposed on the first surface and the second surface, a connection portion disposed on the third surface and the fourth surface, and a corner portion disposed at a corner connecting the band portion and the connection portion and connecting the first surface and the second surface to the third surface and the fourth surface, an external electrode including the same, the external electrode being connected to the first internal electrode and the second internal electrode, a first electrode layer including a first glass, and a second electrode layer disposed on the first electrode layer of the corner portion and including a second glass, the second glass including Fe, and the first glass may not include Fe.

Effects of the Invention

[0010] One of several effects of the present invention is to provide a multilayer electronic component excellent in moisture resistance reliability and high temperature reliability.

[0011] One of several effects of the present invention is to provide a multilayer electronic component in which an increase in equivalent series resistance (ESR) is suppressed.

[0012] However, the various beneficial 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 explaining the specific embodiments of the present invention.

Brief Description of the Drawings

[0013]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Modes for Carrying Out the Invention

[0014] 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 ordinary technicians. Therefore, the shape and size of elements in the drawings can be exaggerated for clearer explanation, and elements denoted by the same reference numerals in the drawings are the same elements.

[0015] In order to clearly describe the present invention in the drawings, parts not related to the description are omitted, and the sizes and thicknesses of the respective components shown in the drawings are arbitrarily shown for convenience of explanation. Therefore, the present invention is not necessarily limited to what is shown in the drawings. For components having the same function within the scope of the same concept, the same reference numerals are used for explanation. Further, throughout the specification, when a certain part refers to a certain component as "including", this means that other components can be further included, rather than excluding other components, unless otherwise stated to the contrary.

[0016] In the figures, 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.

[0017] 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 shows a cross-section corresponding to the cross-section taken along line I-I' of the stacked electronic component according to an example. FIG. 4 is an enlarged view of region P1 in FIG. 1. FIG. 5 is an enlarged view of region P2 in FIG. 1. FIG. 6 is a cross-sectional view taken along line II-II' of FIG. 1.

[0018] Hereinafter, with reference to FIGS. 1 to 6, a stacked electronic component 100 according to an embodiment of the present invention will be described in detail. Further, as an example of the stacked electronic component, a multilayer ceramic capacitor (hereinafter referred to as "MLCC") will be described, but the present invention is not limited thereto.

[0019] The multilayer electronic component 100 according to an embodiment of the present invention includes a dielectric layer 111, and a first internal electrode 121 and a second internal electrode 122 that are alternately arranged in a first direction with the dielectric layer interposed therebetween, and a first surface 1 and a second surface 2 that face each other in the first direction, a third surface 3 and a fourth surface 4 that are connected to the first surface and the second surface and face each other in a second direction, and a fifth surface 5 and a sixth surface 6 that are connected to the first surface, the second surface, the third surface, and the fourth surface and face each other in a third direction. The multilayer electronic component 100 also includes a main body 110, external electrodes 130 and 140 that are arranged on the first surface and the second surface and include band portions B1 and B2, connection portions A1 and A2 that are arranged on the third surface and the fourth surface, and corner portions C1 and C2 that are arranged at corners connecting the band portions and the connection portions and connect the first surface and the second surface to the third surface and the fourth surface. The external electrodes are connected to the internal electrodes and include first electrode layers 131 and 141 that include a first glass, and second electrode layers 132 and 142 that are arranged on the first electrode layers of the corner portions and include a second glass. The second glass may contain Fe, and the first glass may not contain Fe.

[0020] Hereinafter, each configuration included in the multilayer electronic component 100 according to an embodiment of the present invention will be described.

[0021] The main body 110 may have the dielectric layer 111 and the internal electrodes 121 and 122 alternately laminated.

[0022] 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 hexahedron 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 does not have a perfect hexahedron shape with straight lines, but can have a substantially hexahedron shape.

[0023] The main body 110 can have a first surface 1 and a second surface 2 that face each other in a first direction, a third surface 3 and a fourth surface 4 that are connected to the first surface 1 and the second surface 2 and face each other in a second direction, and a fifth surface 5 and a sixth surface 6 that are connected to the first surface 1 and the second surface 2, are connected to the third surface 3 and the fourth surface 4, and face each other in a third direction.

[0024] By overlapping the margin areas where the internal electrodes 121 and 122 are not arranged on the dielectric layer 111, a step due to the thickness of the internal electrodes 121 and 122 is generated, and the corner connecting the first surface and the third, fourth, and fifth surfaces and / or the corner connecting the second surface and the third, fourth, and fifth surfaces can have a form shrunk toward the central side in the first direction of the main body 110 when viewed with reference to the first surface or the second surface. Alternatively, due to the shrinkage behavior during the sintering process of the main body, the corner connecting the first surface 1 and the third, fourth, fifth, and sixth surfaces and / or the corner connecting the second surface 2 and the third, fourth, fifth, and sixth surfaces can have a form shrunk toward the central side in the first direction of the main body 110 when viewed with reference to the first surface or the second surface. Alternatively, in order to prevent chipping defects or the like, by performing a separate process to round the corners connecting the respective surfaces of the main body 110, the corner connecting the first surface and the third, fourth, fifth, and sixth surfaces and / or the corner connecting the second surface and the third, fourth, fifth, and sixth surfaces can have a rounded shape.

[0025] 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 such an extent that it is difficult to confirm without using a scanning electron microscope (SEM). The number of stacked dielectric layers is not 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 stacking 400 or more dielectric layers.

[0026] 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, as the ceramic powder, a barium titanate-based (BaTiO 3)Powder can be used. As a more specific example, the ceramic powder can be a barium titanate-based (BaTiO 3 )-based powder, a CaZrO 3 -based normal dielectric powder, etc. As a more specific example, the barium titanate-based (BaTiO 3 )-based powder can be BaTiO 3 , (Ba 1-x Ca x )TiO 3 (0 < x < 1), Ba(Ti 1-y Ca y )O 3 (0 < y < 1), (Ba 1-x Ca x )(Ti 1-y Zr y )O 3 (0 < x < 1, 0 < y < 1) and Ba(Ti 1-y Zr y )O 3 (0 < y < 1), and one or more of them are acceptable. The CaZrO 3 -based normal dielectric powder can be (Ca 1-x Sr x )(Zr 1-y Ti y )O 3 (0 < x < 1, 0 < y < 1).

[0027] Therefore, the dielectric layer 111 can be BaTiO 3 , (Ba 1-x Ca x )TiO 3 (0 < x < 1), Ba(Ti 1-y Ca y )O 3 (0 < y < 1), (Ba 1-x Ca x )(Ti 1-y Zr y )O 3 (0 < x < 1, 0 < y < 1), Ba(Ti 1-y Zr y )O 3 (0 < y < 1) and (Ca 1-x Sr x )(Zr 1-y Ti y )O 3It can include one or more of (0 < x < 1, 0 < y < 1).

[0028] The average thickness td of the dielectric layer 111 is not particularly limited.

[0029] When aiming for miniaturization and high capacitance of the multilayer electronic component 100, the average thickness td of the dielectric layer 111 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 td of the dielectric layer 111 may be 3 μm or more.

[0030] The average thickness td of the dielectric layer 111 can be measured by scanning an image of a cross-section (L-T cross-section) in the third direction and the first direction of the main body 110 with a scanning electron microscope (SEM).

[0031] For example, the average thickness td of the dielectric layer 111 is such that, among the dielectric layers extracted from an image scanned with a scanning electron microscope (SEM) of a cross-section in the length and thickness directions (L-T) cut at the central portion in the width direction of the main body 110, with respect to a total of 5 dielectric layers including 2 upper layers and 2 lower layers, with reference to the point where the central line in the length direction of the main body and the central line in the thickness direction meet, after determining 5 points including 2 points on the left side and 2 points on the right side at equal intervals around 1 reference point, the average value can be measured by measuring the thickness at each point.

[0032] 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 to face each other with the 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 the first direction.

[0033] The capacitance forming section Ac is a part that contributes to the capacitance formation of the capacitor, and can be formed by repeatedly laminating a plurality of first internal electrodes 121 and second internal electrodes 122 with a dielectric layer 111 interposed therebetween. Also, a first internal electrode 121 can be disposed at the uppermost end of the capacitance forming section Ac in the first direction, and a second internal electrode 122 can be disposed at the lowermost end in the first direction.

[0034] The internal electrodes 121 and 122 can include a first internal electrode 121 and a second internal electrode 122. The first internal electrode 121 and the second internal electrode 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 exposed on the third surface 3 and the fourth surface 4 of the main body 110, respectively.

[0035] The first internal electrode 121 can be exposed via the third surface 3 at a distance from the fourth surface 4, and the second internal electrode 122 can be exposed via the fourth surface 4 at a distance from the third surface 3. A first external electrode 131 can be disposed 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 disposed on the fourth surface 4 of the main body and connected to the second internal electrode 122.

[0036] That is, the first internal electrode 121 is connected to the first external electrode 131 without being connected to the second external electrode 132, and the second internal electrode 122 is connected to the second external electrode 132 without being connected to the first external electrode 131. Therefore, the first internal electrode 121 can be formed at a certain distance apart on the fourth surface 4, and the second internal electrode 122 can be formed at a certain distance apart on the third surface 3. Also, the first internal electrode 121 and the second internal electrode 122 can be disposed at a distance from the fifth surface and the sixth surface of the main body 110.

[0037] The conductive metal included in the internal electrodes 121 and 122 may 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.

[0038] The average thickness te of the internal electrodes 121 and 122 is not particularly limited and can vary according to the purpose. In order to miniaturize the multilayer electronic component 100, the average thickness te of the internal electrodes 121 and 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 and 122 may be 3 μm or more.

[0039] The average thickness te of the internal electrodes 121 and 122 is extracted from an image obtained by scanning, with a scanning electron microscope (SEM), the cross-section in the length and thickness directions (L-T) of a length cut at the central portion in the width direction of the main body 110, of the internal electrode layers. For a total of 5 internal electrode layers, namely 2 upper layers and 2 lower layers, with reference to one internal electrode layer at the point where the central line in the length direction of the main body and the central line in the thickness direction meet, after determining 5 points, namely 2 points on the left side and 2 points on the right side, at equal intervals around the reference point, the thickness at each point is measured, and thus the average value can be measured.

[0040] Cover portions 112 and 113 can be arranged on the upper and lower surfaces of the capacitance forming portion Ac in the first direction.

[0041] The cover portions 112 and 113 can basically play a role in preventing damage to the internal electrodes due to physical or chemical stress.

[0042] The cover portions 112 and 113 can contain the same material as the dielectric layer 111. That is, the cover portions 112 and 113 can contain a ceramic material, for example, a barium titanate (BaTiO 3 )-based ceramic material.

[0043] On the other hand, the thickness of the cover portions 112 and 113 does not need to be particularly limited. For example, the thickness tc1 of the cover portions 112 and 113 may each be 20 μm or less.

[0044] The average thickness tc1 of the cover portions 112 and 113 can represent the size in the first direction, and can be a value obtained by averaging the sizes in the first direction of the cover portions 112 and 113 measured at five equally spaced points above or below the capacitance forming portion Ac.

[0045] Also, margin portions 114 and 115 can be arranged on the side surface of the capacitance forming portion Ac.

[0046] The margin portions 114 and 115 can include a first margin portion 114 arranged on the fifth surface 5 of the main body 110 and a second margin portion 115 arranged on the sixth surface 6. That is, the margin portions 114 and 115 can be arranged on both end surfaces in the width direction of the ceramic main body 110.

[0047] As shown in FIG. 3, the margin portions 114 and 115 can represent the region between the boundary surfaces of both ends of the first internal electrode 121 and the second internal electrode 122 and the main body 110 in a cross-section obtained by cutting the main body 110 in the width-thickness (W-T) direction.

[0048] Basically, the margin portions 114 and 115 can play a role in preventing damage to the internal electrodes due to physical or chemical stress.

[0049] The margin portions 114 and 115 may be formed by applying a conductive paste to form internal electrodes except for the locations where the margin portions are formed on the ceramic green sheet.

[0050] On the other hand, the widths of the margin portions 114 and 115 do not need to be particularly limited. For example, the average widths of the margin portions 114 and 115 may each be 20 μm or less.

[0051] The average widths of the margin portions 114 and 115 can mean the average size in the third direction of the region where the internal electrode is separated from the fifth surface and the average size in the third direction of the region where the internal electrode is separated from the sixth surface, and can be the value obtained by averaging the sizes in the third direction of the margin portions 114 and 115 measured at five equally spaced points on the side surface of the capacitance forming portion Ac.

[0052] The external electrodes 131 and 132 can be arranged on the third surface 3 and the fourth surface 4 of the main body 110.

[0053] The external electrodes 131 and 132 can be respectively arranged on the third surface 3 and the fourth surface 4 of the main body 110, and can include a first external electrode 131 and a second external electrode 132 respectively connected to the first internal electrode 121 and the second internal electrode 122.

[0054] Referring to FIG. 1, the external electrodes 131 and 132 can be arranged so as to cover both end faces in the second direction of the side margin portions 114 and 115.

[0055] In the present embodiment, the structure in which the multilayer electronic component 100 has two external electrodes 131 and 132 is described, but 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.

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

[0057] Referring to FIG. 2, the external electrodes 130 and 140 can include band portions B1 and B2, connection portions A1 and A2, and corner portions C1 and C2.

[0058] Specifically, the external electrodes 130 and 140 can include band portions B1 and B2 arranged on the first surface and the second surface 1 and 2, connection portions A1 and A2 arranged on the third surface and the fourth surface 3 and 4, and corner portions C1 and C2 arranged at the corners connecting the band portions B1 and B2 and the connection portions A1 and A2 and connecting the first surface and the second surface to the third surface and the fourth surface.

[0059] On the one hand, referring to FIGS. 2 and 4, the connection portions A1 and A2 are in the region between the extension line E1 of the first surface and the extension line E2 of the second surface, the band portion B1 is in the region between the extension line E3 of the third surface and the end where the external electrode 130 contacts the main body 110, the band portion B2 is in the region between the extension line E4 of the fourth surface and the end where the external electrode 140 contacts the main body 110, the corner portion C1 is in the region between the extension line E3 of the third surface and the extension lines E1 and E2 of the first and second surfaces, and the corner portion C2 can be meant to be in the region between the extension line E4 of the fourth surface and the extension lines E1 and E2 of the first and second surfaces.

[0060] Also, in FIG. 2, the corner portions C1 and C2 are shown as being arranged at the corners connecting the first and second surfaces and the third and fourth surfaces. However, the corner portions C1 and C2 may be arranged in a form where they connect the third and fourth surfaces and the first, second, fifth, and sixth surfaces. Similarly, the band portions B1 and B2 can be arranged not only on the first surface 1 and the second surface 2 but also on the fifth surface 5 and the sixth surface 6.

[0061] The external electrodes 130 and 140 are connected to the internal electrodes 121 and 122 and can include first electrode layers 131 and 141 including the first glass. The first electrode layers 131 and 141 can play a role of ensuring electrical conduction by being directly connected to the first internal electrode 121 and the second internal electrode 122.

[0062] The first electrode layers 131 and 141 can include the first glass. The first glass can include one or more of Ba, Zn, B, Si, and Al. However, as will be described later, it is preferable that the first glass contained in the first electrode layers 131 and 141 does not contain Fe.

[0063] On the first electrode layers 131 and 141 of the corner portions C1 and C2, second electrode layers 132 and 142 including the second glass can be included. The second electrode layers 132 and 142 can play a role of preventing the penetration of moisture or plating solution from the outside that may occur due to the reduction in the thickness of the corner portions C1 and C2 during the sintering of the first electrode layers 131 and 141.

[0064] The second electrode layers 132 and 142 can include a second glass. The second glass can include one or more of Ba, Zn, B, Si, and Al. However, as will be described later, the second glass included in the second electrode layers 132 and 142 can include Fe.

[0065] On the other hand, the first electrode layers 131 and 141 and the second electrode layers 132 and 142 can include a conductive metal. As the conductive metal, a material having excellent electrical conductivity can be used, but it is not particularly limited. For example, the conductive metal may be one or more of nickel (Ni), copper (Cu), and their alloys.

[0066] According to an embodiment of the present invention, the external electrodes 130 and 140 are connected to the first internal electrode 121 and the second internal electrode 122, are disposed on the first electrode layers 131 and 141 including the first glass and on the first electrode layers 131 and 141 of the corner portions C1 and C2, include the second electrode layers 132 and 142 including the second glass, the second glass includes Fe, and the first glass does not include Fe.

[0067] When the first electrode layers 131 and 141 including the first glass are exposed to an acidic plating solution or moisture, erosion may occur. When the thickness of the first electrode layers 131 and 141 is thick, even if erosion occurs in the first glass on a part of the surface, the internal first glass can prevent the penetration of the plating solution or moisture. However, when the first glass is eroded at a thin portion of the first electrode layers 131 and 141, the plating solution or moisture may penetrate through the thin portion of the first electrode layers 131 and 141, which may cause deterioration of the moisture resistance reliability and high temperature reliability of the multilayer electronic component.

[0068] Therefore, according to an embodiment of the present invention, by disposing the second electrode layers 132 and 142 including the second glass on the first electrode layers 131 and 141 of the corner portions C1 and C2 that are relatively thinly formed, the penetration of the plating solution or moisture can be prevented, and the moisture resistance reliability and high temperature reliability of the multilayer electronic component 100 can be improved.

[0069] On one hand, in order to improve moisture resistance reliability and high-temperature reliability, it is preferable that the second glass contained in the second electrode layers 132 and 142 contains Fe. However, when the first glass contained in the first electrode layers 131 and 141 contains Fe, the connectivity between the internal electrodes 121 and 122 and the first electrode layers 131 and 141 may decrease.

[0070] Therefore, according to an embodiment of the present invention, the second electrode layers 132 and 142 disposed on the first electrode layers 131 and 141 at the corner portions C1 and C2, which are the main penetration paths of the plating solution and external moisture, contain the second glass containing Fe, and the first electrode layers 131 and 141 contain the first glass not containing Fe, whereby the phenomenon of the decrease in the connectivity between the internal electrodes 121 and 122 and the first electrode layers 131 and 141 can be suppressed.

[0071] The method for confirming the feature that the second glass contains Fe and the first glass does not contain Fe is not particularly limited, but one example will be described with reference to FIGS. 4 and 5.

[0072] Referring to FIG. 4, the presence of Fe in the second glass can be determined by performing SEM-EDS (Scanning Electron Microscope-Energy Dispersive X-ray Spectroscopy) analysis on a region R1 of 15 μm × 15 μm in horizontal × vertical with the center point CP, where the extension line E3 of the third surface and the extension line E2 of the second surface meet, in the cross-sections in the first and second directions polished to the center portion in the third direction of the multilayer electronic component 100, under the magnification condition of 1500 times or more and an acceleration voltage of 5 to 20 KV.

[0073] Meanwhile, referring to FIG. 5 , a method for determining that the first glass does not contain Fe can be performed by performing a scanning electron microscope-energy dispersive X-ray spectroscopy (SEM-EDS) analysis on a region R2 of 15 μm×15 μm in width×length, with a center line being a straight line CL that is parallel to the second direction and passes through the center of the multilayer electronic component 100 in the first direction, in a cross section in the first and second directions polished to the center in the third direction of the multilayer electronic component 100, under conditions of an acceleration voltage of 5 to 20 KV and a magnification of 1500 times or more.

[0074] Taking the measurement methods shown in FIGS. 4 and 5 together, Fe can be detected in the R1 region, but not in the R2 region.

[0075] In one embodiment, the thickness of the first electrode layers 131, 141 at the corner portions C1, C2 may be less than the thickness of the first electrode layers at the connection portions A1, A2 and the thickness of the first electrode layers at the band portions B1, B2.

[0076] Since the first electrode layers 131 and 141 contain the first glass, when forming the first electrode layers 131 and 141 on the main body 110, the thicknesses of the first electrode layers 131 and 141 at the corner portions C1 and C2 can be formed thinner than the thicknesses of the first electrode layers at the connection portions A1 and A2 and the thicknesses of the first electrode layers at the band portions B1 and B2. As described above, when the thicknesses of the first electrode layers 131 and 141 at the corner portions C1 and C2 are thinner than those of other regions, the corner regions of the first electrode layers 131 and 141 can be the main penetration paths for moisture or plating solution from the outside. According to an embodiment of the present invention, by disposing the second electrode layers 132 and 142 on the first electrode layers 131 and 141 at the corner portions C1 and C2, and making the second electrode layers 132 and 142 contain a second glass containing Fe, and making the first electrode layers 131 and 141 contain a first glass not containing Fe, the moisture resistance reliability and the high-temperature reliability can be improved. Therefore, even when the thicknesses of the first electrode layers 131 and 141 at the corner portions C1 and C2 are formed thinner than the thicknesses of the first electrode layers at the connection portions A1 and A2 and the thicknesses of the first electrode layers at the band portions B1 and B2, the moisture resistance reliability and the high-temperature reliability of the multilayer electronic component 100 can be ensured.

[0077] The first electrode layers 131 and 141 can have the thinnest thicknesses at the corner portions C1 and C2. However, the connection portions A1 and A2 adjacent to the corner portions C1 and C2 or the band portions B1 and B2 adjacent to the corner portions C1 and C2 may also not be formed with a thickness sufficient for the first electrode layers 131 and 141 to prevent the penetration of moisture and plating solution from the outside. Referring to FIGS. 2 and 4, the second electrode layers 132 and 142 according to an embodiment are also disposed on a part of the first electrode layers 131 and 141 at the connection portions A1 and A2 or on a part of the first electrode layers 131 and 141 at the band portions B1 and B2, whereby the moisture resistance reliability and the high-temperature reliability of the multilayer electronic component 100 can be further improved.

[0078] On the other hand, the thicknesses of the second electrode layers 132 and 142 are not particularly limited. However, in order to ensure sufficient moisture resistance reliability and high temperature reliability, the minimum thickness of the second electrode layers 132 and 142 may be 1 μm or more. The minimum thickness of the second electrode layers 132 and 142 can mean the minimum Feret diameter of the regions where the second electrode layers 132 and 142 are formed in the cross-sections in the first and second directions polished to the center in the third direction of the multilayer electronic component 100, but is not limited thereto.

[0079] The method for forming the first electrode layers 131 and 141 and the second electrode layers 132 and 142 is not particularly limited. For example, the first electrode layers 131 and 141 may be formed by a method of transferring a sheet containing a conductive metal and a first glass onto the main body, or may be formed by a method of transferring a sheet containing a conductive metal and a first glass. Similarly, the second electrode layers 132 and 142 may be formed by a method of transferring a sheet containing a conductive metal and a second glass onto a part of the first electrode layers 131 and 141 after masking the regions except for the positions where the second electrode layers are to be formed, or may be formed by a method of transferring a sheet containing a conductive metal and a second glass.

[0080] The external electrodes 130 and 140 can include plating layers 133, 143, 134, and 144 disposed on the first electrode layers 131 and 141 and the second electrode layers 132 and 142.

[0081] The types of the plating layers 133, 143, 134, and 144 are not particularly limited, and may be plating layers containing one or more of Ni, Sn, Pd, and alloys thereof, and may be formed of a plurality of layers.

[0082] Referring to FIG. 2, the plating layers 133, 143, 134, and 144 can be composed of the first plating layers 133 and 143 and the second plating layers 134 and 144 disposed on the first plating layers 133 and 143.

[0083] The first plating layers 133 and 143 can serve to improve the hermeticity and increase the mechanical strength of the external electrodes. For this purpose, the first plating layers 133 and 143 may be plating layers containing one or more of a Ni plating layer, a Pd plating layer, or an alloy thereof. The second plating layers 134 and 144 may be the outermost layers of the external electrodes 130 and 140, or may be Sn plating layers for improving the mounting characteristics.

[0084] In one embodiment, the first plating layers 133 and 143 can simultaneously cover the first electrode layers 131 and 141 and the second electrode layers 132 and 142 that are not covered by the second electrode layers 132 and 142. Thereby, the hermeticity of the multilayer electronic component 100 can be further improved.

[0085] The size of the multilayer electronic component 100 does not need to be particularly limited.

[0086] For example, the multilayer electronic component 100 can have a size of 0201 (length × width, 0.2 mm × 0.1 mm) or less in order to simultaneously achieve miniaturization and high capacitance, and can have a size of 3216 (length × width, 3.2 mm × 1.6 mm) or more in the case of products where reliability in a high-temperature and high-pressure environment is important, but is not limited thereto.

[0087] Here, the length of the multilayer electronic component 100 can mean the maximum size in the second direction of the multilayer electronic component 100, the thickness of the multilayer electronic component 100 can mean 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.

[0088] On the other hand, referring to FIG. 3, the external electrodes 130' and 140' of the multilayer electronic component 100' according to one embodiment are connected to the first internal electrode 121 and the second internal electrode 122, and are disposed on the first electrode layers 131' and 141' including the first glass at the corner portions C1 and C2, and include second electrode layers 132' and 142' including the second glass, the second glass can contain Fe, and the first glass can not contain Fe.

[0089] Further, the external electrodes 130' and 140' of the multilayer electronic component 100' according to an embodiment may further include conductive resin layers 135' and 145' that cover the first electrode layers 131' and 141' not covered by the second electrode layers 132' and 142'. Thereby, the bending strength of the multilayer electronic component 100' can be improved.

[0090] The conductive resin layers 135' and 145' can include a conductive filler and a resin. The conductive filler can include one or more of Cu, Ni, Ag, Sn, and Cr, and the conductive filler can be present in a form dispersed in the resin of the conductive resin layers 135' and 145'. The resin can include a resin with strong heat resistance. For example, it can include one or more of phenolic resin, urea resin, diallyl phthalate resin, melanin resin, guanamine resin, unsaturated polyester resin, polyurethane resin, epoxy resin, acrylic resin, ethyl cellulose resin, amino alkyd resin, melamine-urea co-condensation resin, silicone resin, and polysiloxane resin, but is not limited thereto.

[0091] On the other hand, since the conductive resin layers 135' and 145' are softer than the electrode layers containing glass, plating defects may occur due to the stress generated during the plating process. Also, since the conductive resin layers 135' and 145' have the conductive filler present in a form dispersed in the resin, there may be a problem that it is difficult to reduce the ESR compared to the electrode layer.

[0092] Therefore, in one embodiment, by arranging the conductive resin layers 135' and 145' to cover a part of the second electrode layers 132' and 142', direct connection between the second electrode layers 132' and 142' and the first plating layers 133' and 143' can be enabled. Thereby, the plating property and ESR characteristics of the multilayer electronic component 100' can be improved.

[0093] Specifically, referring to FIG. 3, the external electrodes 130' and 140' further include a second electrode layer 132' and 142' not covered by the conductive resin layers 135' and 145', and a first plating layer 133' and 143' disposed on the conductive resin layers 135' and 145'. A part of the first plating layers 133' and 143' can be in contact with a part of the second electrode layers 132' and 142' not covered by the conductive resin layers 135' and 145'. Thereby, the plating property and the ESR characteristics of the multilayer electronic component 100' can be improved.

[0094] On the other hand, a second plating layer 134' and 144' can be disposed on the first plating layers 133' and 143'. At this time, since the components of the first plating layers 133' and 143' and the second plating layers 134' and 144' can be the same as those of the first plating layers 133 and 143 and the second plating layers 134 and 144 described above, duplicate descriptions are omitted.

[0095] (Experimental Example) Table 1 below evaluates the high-temperature reliability and moisture resistance reliability of Comparative Example 1 and Example 1, and shows the number of samples in which failures occurred.

[0096] Comparative Example 1 is a case where no second electrode layer is formed and Fe is not detected in the entire region of the external electrode. Example 1 is a case where it has a first electrode layer and a second electrode layer as in an embodiment of the present invention, the glass of the second electrode layer contains Fe, and the glass of the first electrode layer does not contain Fe.

[0097] In the case of high-temperature reliability, it is evaluated for 12 hours under the conditions of 105 °C and 1 Vr. In the case of moisture resistance reliability, it is evaluated for 12 hours under the conditions of 85 °C, 85 RH% (relative humidity), and 0.6 Vr, and the number of evaluation samples is 100. When the resistance value measured at the end of the evaluation is reduced by 10 3 Ω or more compared to the initial value, it is determined as NG.

[0098] [Table 1]

[0099] Referring to Table 1, it can be confirmed that the high-temperature reliability and moisture resistance reliability of Example 1 are superior to those of Comparative Example 1.

[0100] Therefore, in the case of a comparative example having a first electrode layer and a second electrode layer as in an embodiment of the present invention, wherein the glass of the second electrode layer contains Fe and the glass of the first electrode layer contains Fe, it can be confirmed that the high-temperature reliability and moisture resistance reliability are improved.

[0101] Table 2 below shows the number of samples in which plating breakage occurred for Comparative Example 2 and Example 2.

[0102] Comparative Example 2 is a case where the second electrode layer is not formed and Fe is not detected in the entire region of the external electrode. Example 2 is a case having a first electrode layer and a second electrode layer as in an embodiment of the present invention, wherein the glass of the second electrode layer contains Fe and the glass of the first electrode layer does not contain Fe. On the other hand, both Comparative Example 2 and Example 2 include a Ni plating layer and a Sn plating layer disposed on the Ni plating layer.

[0103] After mounting 30 samples of Example 2 and 30 samples of Comparative Example 2 on the surfaces in the first direction and the third direction and peeling the Sn plating layer, the number of occurrences of plating breakage at the points (triple points) where the three surfaces of the main body meet was confirmed. Since there are 4 triple points per sample, the number of occurrences of plating breakage was created based on 120 in Table 2 below.

[0104]

Table 2

[0105] Referring to Table 2, in the case of Comparative Example 2, it can be confirmed that there are more poor plating finish cases than in Example 2. This is because in the case of Comparative Example 2, as a result of not forming the second electrode layer as in the present invention, the electrode layer of the external electrode cannot form a sufficient thickness at the triple point, and the plating peels off or breaks. On the other hand, in the case of Example 2, it has the first electrode layer and the second electrode layer as in an embodiment of the present invention, the glass of the second electrode layer contains Fe, and the glass of the first electrode layer does not contain Fe. Therefore, it is expected that the thickness of the electrode layer at the corner portion is ensured to be sufficiently thick, and the glass containing Fe prevents erosion by the plating solution, resulting in improved plating properties.

[0106] Table 3 below shows a comparison of the capacitance characteristics, contact properties, and ESR characteristics between Comparative Example 3 and Example 3.

[0107] Comparative Example 3 is a case where the glass containing Fe is uniformly distributed in the electrode layer and Fe is detected even at the center of the electrode layer in the thickness direction. In the case of Example 3, it has the first electrode layer and the second electrode layer as in an embodiment of the present invention, the glass of the second electrode layer contains Fe, and Fe is not detected at the center of the first electrode layer in the thickness direction.

[0108] The capacitance measurement was the result after performing heat treatment at 150°C for 1 hour and then Aging for 2 hours. (n = 50) For the capacitance, when the capacitance percentage did not fall within a 10% deviation considering Aging, it was determined as NG.

[0109] In the case of contact properties, when the percentage with respect to the reference capacitance was 70% or less, it was determined that there was contact, and when it was less than 70%, it was determined as defective. In the case of ESR, 100 samples were mounted on a dedicated substrate and measured at 1 MHz.

[0110]

Table 3

[0111] Referring to Table 3, in the case of Example 3, it can be confirmed that the number of NG in terms of capacitance is less and the number of poor contact is less than that of Comparative Example 3, and it can also be confirmed that the ESR characteristics of Example 3 are superior to those of Comparative Example 3.

[0112] In the case of Comparative Example 3 where Fe exists in the central part in the thickness direction of the electrode layer, it is expected that this is the result of preventing the connectivity between the internal electrode and the electrode layer, inducing capacitance reduction and poor contact, and also improving the ESR.

[0113] Table 4 below shows a comparison of the plating breakage defects and ESR characteristics between Comparative Example 4 and Example 4.

[0114] Example 4 includes a first electrode layer and a second electrode layer as in an embodiment of the present invention, and a conductive resin layer, a Ni plating layer, and a Sn plating layer are sequentially arranged on the second electrode layer and the first electrode layer, and the conductive resin layer covers a part of the second electrode layer and does not cover a part, and a part of the second electrode layer and a part of the Ni plating layer are in direct contact. In the case of Comparative Example 4, it includes a first electrode layer and a second electrode layer, and a conductive resin layer, a Ni plating layer, and a Sn plating layer are sequentially arranged on the second electrode layer and the first electrode layer, and the conductive resin layer covers all of the second electrode layer.

[0115] After mounting 30 samples of Example 4 and 30 samples of Comparative Example 4 on the surfaces in the first direction and the third direction and peeling off the Sn plating layer, the number of occurrences of plating breakage at the point where the three surfaces of the main body meet (triple point) was confirmed. Since there are 4 triple points per sample, the number of occurrences of plating breakage was created based on 120 in Table 4 below.

[0116] In the case of ESR, 100 samples were mounted on a dedicated substrate and measured at 1 MHz.

[0117]

Table 4

[0118] Referring to Table 4, in the case of Example 4, it can be confirmed that the occurrence of poor plating finish is less than that of Comparative Example 4, and it can also be confirmed that the ESR characteristics are excellent.

[0119] In the case of Example 4, it is expected that since the second electrode layer is not completely covered by the conductive resin layer and a part thereof is exposed and directly contacts the Ni plating layer, poor plating finish due to erosion of the glass is prevented and the ESR characteristics are also improved.

[0120] As described above, the embodiments of the present invention have been described in detail. However, the present invention is not limited by the above-described embodiments and the accompanying drawings, but is limited by the appended claims. Therefore, various forms of substitution, modification, and change can be made by those having ordinary knowledge in the technical field without departing from the technical idea of the present invention described in the claims, and this can also be said to belong to the scope of the present invention.

[0121] In addition, the expression "one embodiment" used in the present invention does not mean the same embodiment, but is provided to emphasize and explain each different unique feature. However, the above-described embodiments do not exclude being realized in combination with the features of other embodiments. For example, even if the matter described in a specific embodiment is not described in another embodiment, it can be understood as an explanation related to the other embodiment as long as there is no explanation contrary to or conflicting with that matter in the other embodiment.

[0122] The terms used in the present invention are merely used to explain one embodiment and are not intended to limit the present invention. At this time, the singular expression includes plural expressions unless the context clearly indicates a different meaning.

Description of Reference Numerals

[0123] 100: Multilayer electronic component 110: Body 111: Dielectric layer 112, 113: Cover part 114, 115: Margin part 121, 122: Internal electrode 130, 140, 130', 140': External electrode 131, 141, 131', 141': First electrode layer 132, 142, 132', 142': Second electrode layer 133, 143, 133', 143': First plating layer 134, 144, 134', 144': Second plating layer 135', 145': Conductive resin layer

Claims

1. a main body including a dielectric layer and first internal electrodes and second internal electrodes alternately disposed in a first direction with the dielectric layer sandwiched therebetween, the main body including a first surface and a second surface facing the first direction, a third surface and a fourth surface connected to the first surface and the second surface and facing the second direction, and a fifth surface and a sixth surface connected to the first surface, the second surface, the third surface, and the fourth surface and facing the third direction; an external electrode including a band portion disposed on the first surface and the second surface, a connection portion disposed on the third surface and the fourth surface, and a corner portion connecting the band portion and the connection portion and disposed at a corner connecting the first surface and the second surface and the third surface and the fourth surface, the external electrode includes a first electrode layer connected to the first internal electrode and the second internal electrode and including a first glass; and a second electrode layer disposed on the first electrode layer in the corner portion and including a second glass; The multilayer electronic component, wherein the second glass contains Fe and the first glass does not contain Fe.

2. 2. The multilayer electronic component according to claim 1, wherein a thickness of the first electrode layer in the corner portion is thinner than a thickness of the first electrode layer in the connection portion and a thickness of the first electrode layer in the band portion.

3. 2 . The multilayer electronic component according to claim 1 , wherein the second electrode layer is also disposed on a portion of the first electrode layer of the connection portion or a portion of the first electrode layer of the band portion.

4. The multilayer electronic component according to claim 1 , wherein the first glass contains at least one of Ba, Zn, and Al, and the second glass further contains at least one of Ba, Zn, and Al.

5. 2. The multilayer electronic component according to claim 1, wherein the second electrode layer has a minimum thickness of 1 [mu]m or more.

6. 2. The multilayer electronic component according to claim 1, wherein the external electrodes further include a first plating layer disposed on the first electrode layer and the second electrode layer, and a second plating layer disposed on the first plating layer.

7. 7. The multilayer electronic component according to claim 6, wherein the first plating layer simultaneously covers the first electrode layer and the second electrode layer that are not covered by the second electrode layer.

8. 8. The multilayer electronic component according to claim 1, wherein the external electrodes further include a conductive resin layer that covers the first electrode layers that are not covered by the second electrode layers.

9. The multilayer electronic component according to claim 8 , wherein the conductive resin layer covers a part of the second electrode layer.

10. the external electrode further includes a second electrode layer that is not covered by the conductive resin layer and a first plating layer disposed on the conductive resin layer, 10. The multilayer electronic component according to claim 9, wherein a portion of the first plating layer is in contact with a portion of the second electrode layer that is not covered with the conductive resin layer.

11. The multilayer electronic component according to claim 10 , wherein the external electrodes further include a second plating layer disposed on the first plating layer.

12. The multilayer electronic component according to claim 8 , wherein the conductive resin layer contains a metal filler and a resin.

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