Multilayer electronic component

Abstract

To provide a multilayer electronic component with a high reliability, in which an internal electrode and an external electrode are electrically connected more strongly and the volume per unit of the multilayer electronic component is improved.SOLUTION: The multilayer electronic component according to an embodiment of the present invention includes: a body including a dielectric layer and internal electrodes alternately arranged across the dielectric layer; an interface plating layer arranged in an edge of the internal electrodes, the interface plating layer containing at least one of B and P and containing Ni; and an external electrode covering the interface plating layer, the external electrode including a glass containing Si and Al and an electrode layer containing a conductive metal. The electrode layer includes an internal region adjacent to the interface plating layer and an external region arranged on the internal region. The area fraction of glass in the internal region is higher than the area fraction of glass in the external region.SELECTED DRAWING: Figure 6

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-shaped capacitor that is mounted on a printed circuit board of various electronic products such as liquid crystal display (LCD) devices and plasma display panel (PDP) devices, computers, smartphones, and mobile phones, and serves to charge or discharge electricity.

[0003] The multilayer ceramic capacitor can be used as a component of various electronic devices because it has the advantages of being small in size, having a high capacitance, and being easy to mount.

[0004] Recently, with the miniaturization and high performance of electronic devices, multilayer ceramic capacitors also tend to be miniaturized and have a higher capacitance, and the importance of ensuring the high reliability of multilayer ceramic capacitors has increased due to such a trend.

[0005] In order to miniaturize such a multilayer ceramic capacitor, there is a tendency to reduce the thickness of the external electrode, and even if the thickness of the external electrode is reduced, a solution that can ensure reliability in a high-temperature and high-humidity environment is required.

Summary of the Invention

Problems to be Solved by the Invention

[0006] One of the various objects of the present invention is to provide a multilayer electronic component with excellent reliability.

[0007] One of the various objects of the present invention is to improve the electrical connectivity between the internal electrode and the external electrode.

[0008] One of the various objects of the present invention is to improve the capacitance per unit volume of a multilayer electronic component.

[0009] 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 specific embodiments of the present invention.

Means for Solving the Problems

[0010] A multilayer electronic component according to an embodiment of the present invention includes a dielectric layer, a main body including internal electrodes alternately arranged with the dielectric layer, an interface plating layer disposed at an end of the internal electrode, and an external electrode including an electrode layer disposed so as to cover the interface plating layer and including glass containing Si and Al and a conductive metal. The electrode layer includes an inner region adjacent to the interface plating layer and an outer region disposed on the inner region, and the area fraction of the glass contained in the inner region may be higher than the area fraction of the glass contained in the outer region.

Effects of the Invention

[0011] As one of the various effects of the present invention, by including glass containing Si and Al in the electrode layer and disposing an interface plating layer at the end of the internal electrode, the reliability of the multilayer electronic component can be improved.

[0012] As one of the various effects of the present invention, the electrical connectivity between the internal electrode and the external electrode can be improved.

[0013] As one of the various effects of the present invention, the capacitance per unit volume of the multilayer electronic component can be improved.

[0014] However, the various 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 explaining specific embodiments of the present invention.

Brief Description of the Drawings

[0015]

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Figure 6

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Figure 12

Embodiments for Carrying Out the Invention

[0016] 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 several 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 an ordinary technician. Therefore, the shape and size of elements in the drawings may be enlarged, reduced (or emphasized or simplified) for clearer explanation, and elements denoted by the same reference numerals in the drawings are the same elements.

[0017] In addition, for the purpose of clearly explaining the present invention in the drawings, parts not related to the explanation are omitted, and the sizes and thicknesses of the illustrated components are arbitrarily shown for convenience of explanation. Therefore, the present invention is not necessarily limited by the illustration. Also, components with the same functions within the scope of the same concept can be 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.

[0018] 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.

[0019] Stacked 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 schematically shows the main body disassembled, FIG. 5 schematically shows a part of the main body of FIG. 2, and FIG. 6 is an enlarged view showing an enlarged K1 region of FIG. 2.

[0020] Hereinafter, with reference to FIGS. 1 to 6, 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.

[0021] The multilayer electronic component 100 according to an embodiment of the present invention includes a main body 110 including a dielectric layer 111 and internal electrodes 121 and 122 alternately arranged with the dielectric layer, interface plating layers 141 and 142 arranged at the ends of the internal electrodes, and external electrodes 131 and 132 including electrode layers 131a and 132a arranged to cover the interface plating layers and containing glass GL1 and GL2 containing Si and Al and conductive metals M1 and M2. The electrode layer includes an inner region 131a1 adjacent to the interface plating layer and an outer region 131a2 arranged on the inner region, and the area fraction of the glass GL1 contained in the inner region can be higher than the area fraction of the glass GL2 contained in the outer region.

[0022] In order to miniaturize the multilayer ceramic capacitor, there is a tendency to reduce the thickness of the external electrode, and a solution is needed to ensure reliability in a high-temperature and high-humidity environment even when the thickness of the external electrode is reduced.

[0023] Therefore, a solution was considered to change the glass component contained in the electrode layer to a glass containing Si and Al, which is a plating-resistant liquid glass effective for improving reliability, to prevent the plating solution and moisture from penetrating.

[0024] However, when applying glass containing Si and Al to the electrode layer, although it is possible to prevent a decrease in reliability due to the penetration of the plating solution, moisture, etc., there is a problem that the glass containing Si and Al during the firing of the electrode layer moves to the interface with the main body, inducing oxidation at the end of the internal electrode and reducing the connectivity between the internal electrode and the external electrode.

[0025] According to an embodiment of the present invention, glass containing Si and Al is included in the electrode layer, and an interfacial plating layer is disposed at the end of the internal electrode to suppress oxidation of the end of the internal electrode and improve reliability, while improving the connectivity between the internal electrode and the external electrode.

[0026] Hereinafter, each component included in the multilayer electronic component 100 according to an embodiment of the present invention will be described.

[0027] The main body 110 can have a dielectric layer 111 and internal electrodes 121 and 122 alternately laminated.

[0028] 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 does not have a perfect hexahedral shape with straight lines, but can have a substantially hexahedral shape.

[0029] The main body 110 can have a first surface 1 and a second surface 2 facing each other in a first direction, a third surface 3 and a fourth surface 4 connected to the first surface 1 and the second surface 2 and facing each other in a second direction, and a fifth surface 5 and a sixth surface 6 connected to the first surface 1 and the second surface 2, connected to the third surface 3 and the fourth surface 4, and facing each other in a third direction.

[0030] When a margin region where the internal electrodes 121 and 122 are not disposed overlaps 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. Or, due to the shrinkage behavior during the sintering process of the main body, the corner connecting the first surface 1 and the third surface 3, fourth surface 4, fifth surface 5, and sixth surface 66 and / or the corner connecting the second surface 2 and the third surface 3, fourth surface 4, fifth surface 5, and sixth surface 6 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. Or, in order to prevent chipping defects or the like, the corners connecting the respective surfaces of the main body 110 are rounded by performing a separate process, so that 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 form.

[0031] On the other hand, in order to suppress the step due to the internal electrodes 121 and 122, after cutting so that the internal electrodes are exposed on the fifth surface 5 and the sixth surface 6 of the main body after lamination, when a single dielectric layer or two or more dielectric layers are laminated in the third direction (width direction) on both side surfaces of the capacitance forming portion Ac to form the margin portions 114 and 115, the portions connecting the first surface and the fifth and sixth surfaces and the portions connecting the second surface and the fifth and sixth surfaces can have a non-shrunk form.

[0032] The plurality of dielectric layers 111 forming the main body 110 are in a fired state, and the boundaries between adjacent dielectric layers 111 can be integrated to such an extent that they are difficult to confirm without using a scanning electron microscope (SEM). The number of laminated dielectric layers is not particularly limited and can be determined in consideration of the size of the laminated electronic component. For example, the main body can be formed by laminating 400 or more dielectric layers.

[0033] 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-based (BaTiO 3 ) powder can be used as the ceramic powder. More specifically, for example, the ceramic powder can be one or more of 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).

[0034] The average thickness td of the dielectric layer 111 does not need to be particularly limited. For example, it can be 0.01 μm to 10 μm. Also, the average thickness td of the dielectric layer 111 can be arbitrarily set according to desired characteristics and applications. For example, in the case of small IT electronic components, in order to achieve miniaturization and high capacitance, the average thickness td of at least one of the plurality of dielectric layers 111 can be 0.4 μm or less.

[0035] Here, the average thickness td of the dielectric layer 111 can mean the size in the first direction of the dielectric layer 111 disposed between the internal electrodes 121 and 122. The average thickness of the dielectric layer 111 can be measured by scanning the cross-sections in the first and second directions of the main body 110 with a scanning electron microscope (SEM) at a magnification of 10,000 times. More specifically, the thickness can be measured at a number of points of one dielectric layer 111, for example, 30 points at equal intervals in the second direction, and the average value can be measured. The 30 points at the above equal intervals can be specified by the capacitance forming portion Ac described later. Further, when such average value measurement is extended to 10 dielectric layers 111 to measure the average value, the average thickness of the dielectric layer 111 can be further generalized.

[0036] 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 in the first direction of the capacitance forming portion Ac.

[0037] 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 internal electrodes 121 and second internal electrodes 122 with the dielectric layer 111 interposed therebetween.

[0038] The cover portions 112 and 113 can include an upper cover portion 112 disposed on the upper portion in the first direction of the capacitance forming portion Ac and a lower cover portion 113 disposed on the lower portion in the first direction of the capacitance forming portion Ac.

[0039] The upper cover portion 112 and the lower 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, and can basically serve to prevent damage to the internal electrodes due to physical or chemical stress.

[0040] The upper cover portion 112 and the lower cover portion 113 do not include internal electrodes and can include the same material as the dielectric layer 111.

[0041] That is, the upper cover portion 112 and the lower cover portion 113 can include a ceramic material, for example, barium titanate (BaTiO 3 )-based ceramic material.

[0042] On the other hand, the thickness of the cover portions 112 and 113 does not need to be particularly limited. However, in order to more easily achieve miniaturization and high capacitance of the multilayer electronic component, the thickness tc of the cover portions 112 and 113 can be 15 μm or less.

[0043] The average thickness tc of the cover portions 112 and 113 can mean 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.

[0044] Also, margin portions 114 and 115 can be arranged on the side surfaces of the capacitance forming portion Ac.

[0045] 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.

[0046] As shown in FIG. 3, the margin portions 114 and 115 can mean the region between the interfaces 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.

[0047] The margin portions 114 and 115 can basically play a role in preventing damage to the internal electrodes due to physical or chemical stress.

[0048] 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.

[0049] Also, in order to suppress the step formed by the internal electrodes 121 and 122, after cutting so that the internal electrodes are exposed on the fifth surface 5 and the sixth surface 6 of the main body after lamination, a single dielectric layer or two or more dielectric layers are laminated in the third direction (width direction) on both side surfaces of the capacitance forming portion Ac to form the margin portions 114 and 115.

[0050] On the other hand, the width of the margin portions 114 and 115 does not need to be particularly 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.

[0051] 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 are separated from the fifth surface and the average size in the third direction of the region where the internal electrodes are 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] Therefore, in one embodiment, 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 sixth surface can be 15 μm or less, respectively.

[0053] On the other hand, when a magnetic material is applied to the main body 110 instead of the dielectric material, the multilayer electronic component can function as an inductor. The magnetic material can be, for example, ferrite and / or metal magnetic particles. When the multilayer electronic component functions as an inductor, the internal electrode can be a coil-shaped conductor.

[0054] Also, when a piezoelectric material is applied to the main body 110 instead of a dielectric material, the multilayer electronic component can function as a piezoelectric element. The piezoelectric material can be, for example, PZT (lead zirconate titanate).

[0055] Also, when a ZnO-based or SiC-based material is applied to the main body 110 instead of a dielectric material, the multilayer electronic component can function as a varistor, and when a spinel-based material is applied to the main body 110 instead of a dielectric material, the multilayer electronic component can function as a thermistor.

[0056] That is, the multilayer electronic component 100 according to an embodiment of the present invention can function not only as a multilayer ceramic capacitor but also as an inductor, a piezoelectric element, a varistor, or a thermistor by appropriately changing the material and structure of the main body 110.

[0057] The internal electrodes 121 and 122 can be alternately arranged with the dielectric layer 111. For example, a first internal electrode 121 and a second internal electrode 122, which are a pair of electrodes having different polarities from each other, can be arranged so as to face each other with the dielectric layer 111 interposed therebetween. The first internal electrode 121 and the second internal electrode 122 can be electrically separated from each other by the dielectric layer 111 disposed therebetween. At this time, the internal electrodes 121 and 122 can be alternately arranged with the dielectric layer 111 in the first direction.

[0058] The first internal electrode 121 can be separated from the fourth surface 4 and extend toward the third surface 3. The second internal electrode 122 can be separated from the third surface 3 and extend toward the fourth surface 4. The first internal electrode 121 can be electrically connected to the first external electrode 131 on the third surface 3 side, and the second internal electrode 122 can be electrically connected to the second external electrode 132 on the fourth surface 4 side.

[0059] The conductive metal contained in the internal electrodes 121 and 122 can be one or more of Ni, Cu, Pd, Ag, Au, Pt, Sn, W, Ti, and alloys thereof, and more preferably can contain Ni, but the present invention is not limited thereto.

[0060] The method for forming the internal electrodes 121 and 122 is not particularly limited. For example, the internal electrodes 121 and 122 can be formed by applying a conductive paste for internal electrodes containing a conductive metal on a ceramic green sheet and firing it. As the method for applying the conductive paste for internal electrodes, a screen printing method, a gravure printing method, or the like can be used, but the present invention is not limited thereto.

[0061] The average thickness te of the internal electrodes 121 and 122 does not need to be particularly limited, but for example, it can be 0.01 μm to 3 μm or less. Further, 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 small IT electronic components, in order to achieve miniaturization and high capacitance, the average thickness te of at least one of the plurality of internal electrodes 121 and 122 can be 0.4 μm or less.

[0062] Here, the average thickness te of the internal electrode can be measured by scanning a cross-section of the main body 110 in the first direction and the second direction with a scanning electron microscope (SEM) at a magnification of 10,000 times. More specifically, the thickness can be measured at a large number of points of one internal electrode 121 or 122, for example, 30 points at equal intervals in the second direction, and the average value can be measured. The 30 points at the above equal intervals can be specified in the capacitance forming portion Ac. Further, when such average value measurement is extended to 10 internal electrodes 121 and 122 to measure the average value, the average thickness of the internal electrodes 121 and 122 can be further generalized.

[0063] The external electrodes 131 and 132 are arranged so as to cover the interface plating layers 141 and 142, and can include electrode layers 131a and 132a containing glass GL1 and GL2 containing Si and Al and conductive metals M1 and M2.

[0064] As shown in FIG. 2, the external electrodes 131 and 132 are respectively disposed on the third surface 3 and the fourth surface 4 of the main body 110, and may include a first external electrode 131 and a second external electrode 132 that are respectively connected to the first internal electrode 121 and the second internal electrode 122 via the interface plating layers 141 and 142. The first external electrode 131 may include a first electrode layer 131a, and the second external electrode 132 may include a second electrode layer 132a.

[0065] In the present 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.

[0066] FIG. 6 is an enlarged view showing an enlarged view of the K1 region in FIG. 2.

[0067] The above K1 region shows an enlarged view of a part of the portion where the first external electrode 131 is disposed. However, the first external electrode 131 is disposed on the third surface, and the second external electrode 132 is disposed on the fourth surface. Only the difference is that the configurations of the first external electrode 131 and the second external electrode 132 are similar. Therefore, hereinafter, the description will be made based on the first external electrode 131, which is considered to include the description regarding the second external electrode 132. Also, the electrode layers 131a and 132a will be described based on the first electrode layer 131a, which is regarded as including the description regarding the second electrode layer 132a. Further, the interface electrode layers 141 and 142 will be described based on the first interface electrode layer 141, which is considered to include the description regarding the second interface electrode layer 142.

[0068] Conventionally, as the glass contained in the electrode layer, a Ba-Zn-based glass containing Ba and Zn was used. However, since the Ba-Zn-based glass is easily soluble in the plating solution, when the Ba-Zn-based glass is used, there is a risk that the plating solution, moisture, etc. may penetrate into the internal electrode. When the thickness of the electrode layer is reduced, there is a problem that the possibility of the plating solution, moisture, etc. penetrating into the internal electrode increases.

[0069] Therefore, in the present invention, the electrode layers 131a and 132a are made to contain glasses GL1 and GL2 containing Si and Al, which are excellent in plating liquid resistance with respect to Ba-Zn-based glass, in an attempt to improve moisture resistance reliability. Here, the glasses GL1 and GL2 containing Si and Al can mean aluminosilicate-based glasses.

[0070] In the case of the glasses GL1 and GL2 containing Si and Al, although they are excellent in plating liquid resistance, there is a risk of inducing oxidation of the end portions of the internal electrodes by moving to the interface with the internal electrodes during the firing process and promoting oxide formation at the end portions of the internal electrodes. Therefore, when changing the glass contained in the electrode layer from Ba-Zn-based glass to glasses GL1 and GL2 containing Si and Al, there may arise a problem of reducing the connectivity between the external electrode and the internal electrode.

[0071] Referring to FIG. 6, the first electrode layer 131a includes an inner region 131a1 adjacent to the first interface plating layer 141 and an outer region 131a2 disposed on the inner region. The area fraction of the glass GL1 contained in the inner region 131a1 is higher than the area fraction of the glass GL2 contained in the outer region 131a2. This is considered to be due to the fact that the glasses GL1 and GL2 containing Si and Al are excellent in wettability with the main body 110 and move to the main body side during the firing process. Thus, when the area fraction of the glass GL1 contained in the inner region 131a1 is higher than the area fraction of the glass GL2 contained in the outer region 131a2, oxidation of the end portions of the internal electrodes can be induced by promoting oxide formation at the end portions of the internal electrodes. However, according to the present invention, the interface plating layers 141 and 142 are disposed at the end portions of the internal electrodes 121 and 122, and oxidation of the end portions of the internal electrodes can be prevented.

[0072] That is, according to one embodiment of the present invention, by disposing the interface plating layers 141 and 142 at the ends of the internal electrodes 121 and 122, oxidation of the ends of the internal electrodes 121 and 122 can be suppressed to improve reliability while improving the connectivity between the internal electrodes and the external electrodes. Further, since moisture resistance reliability can be ensured even when the external electrodes 131 and 132 are formed thinly, the capacitance per unit volume can be improved.

[0073] There is no particular need to limit the relationship between the area fractions of the glass contained in the inner region 131a and the outer region 132a and each numerical value.

[0074] As a preferable example, the area fraction of the glass GL1 contained in the inner region 131a1 can be three times or more the area fraction of the glass GL2 contained in the outer region 131a2.

[0075] Also, the area fraction of the glass GL1 contained in the inner region 131a1 can be 80% or more, and the area fraction of the glass GL2 contained in the outer region 131a2 can be 30% or less.

[0076] The area fractions of the glass contained in the inner region 131a and the outer region 132a can be measured by an image obtained by scanning the electrode layers 131a and 132a at a magnification of 1500 times or more using a scanning electron microscope (SEM) in cross-sections in the first and second directions obtained by cutting the multilayer electronic component 100 at the center in the third direction of the main body 110. Referring to FIGS. 11 and 12, since there is a large difference in brightness between the glass and the conductive metal in the image scanned by the SEM, they can be visually and clearly distinguished, and the area fraction can be obtained using an image analysis program. Further, the metal of the interface plating layer 141 and the electrode layers 131a and 132a can be distinguished by performing elemental analysis using SEM-EDS.

[0077] Specifically, when the interface plating layer 141 has a semi-circular shape, a region of 10 μm × 2.5 μm (size in the first direction × size in the second direction) is selected from the region within 5 μm in the second direction from the main body 110, scanned using SEM-EDS, and then the glass area (GLS1, unit: μm 2 ) and the area of the interface plating layer (PS, unit: μm 2 ) are measured, and GLS1 / (25 μm 2 - PS) × 100 (%) can be used as the glass area fraction of the inner region 131a1. On the other hand, when the interface plating layer 141' has a layered shape according to a modification example of the present invention, a region of 10 μm × 2.5 μm (size in the first direction × size in the second direction) can be selected in the region within 5 μm in the second direction from the interface plating layer 141'. However, when the average thickness of the inner region 131a1 is less than 2.5 μm, the measurement region can be 4 μm × 1 μm (size in the first direction × size in the second direction).

[0078] Also, for the glass area fraction of the outer region 131a2, a region of 10 μm × 2.5 μm (size in the first direction × size in the second direction) is selected from the region within 10 μm in the second direction from the outer surface of the electrode layer 131a, scanned using SEM-EDS, and then the glass area (GLS2, unit: μm 2 ) is measured. After that, GLS2 / 25 μm 2 × 100 (%) can be used as the glass area fraction of the outer region 131a2.

[0079] On the other hand, the area fraction of the conductive metal M1 contained in the inner region 131a1 can be lower than the area fraction of the conductive metal M2 contained in the outer region 131a2.

[0080] The average thickness of the inner region 131a1 can vary depending on firing conditions, the form and type of the interface plating layer, etc. However, when applying general firing conditions, the average thickness of the inner region 131a1 can be 1 μm or more and 5 μm or less. The average thickness of the inner region 131a1 can be the average value of the values measured at 10 equally spaced points in the first direction in the image scanned by the above SEM.

[0081] When applying general firing conditions, since the average thickness of the inner region 131a1 is 1 μm or more, the glass area fraction can be 80% or more in the region within 1 μm from the interface with the above interface plating layer in the inner region.

[0082] In one embodiment, the glasses GL1 and GL2 can further contain Fe. When the glasses GL1 and GL2 further contain Fe and the interface plating layers 141 and 142 do not exist, the Fe contained in the glasses GL1 and GL2 can move to the ends of the internal electrodes 121 and 122 to form Ni—Fe—O, and Ni—Fe—O can further promote the oxidation of the ends of the internal electrodes 121 and 122. Therefore, when the glasses GL1 and GL2 further contain Fe, the effect of suppressing the oxidation of the ends of the internal electrodes 121 and 122 due to the arrangement of the interface plating layers 141 and 142 of the present invention can be made more remarkable.

[0083] In one embodiment, the glasses GL1 and GL2 are SiO 2 , Al 2 O 3 , and Fe 2 O 3 and can contain. Further, Si, Al, and Fe contained in the glasses GL1 and GL2 can be contained in the form of SiO 2 -Al 2 O 3 -Fe 2 O 3 of.

[0084] In one embodiment, the glasses GL1 and GL2 can further contain an alkali oxide. The alkali oxide can control the formation of oxygen bridges in the glasses GL1 and GL2 to lower the softening point, thereby improving the density of the electrode layer. Here, the density of the electrode layer means the degree to which pores are generated on the surface when the voids generated during the sintering of the conductive metal during the electrode firing process are not filled by the glass softening behavior. When the surface density of the electrode deteriorates, the pores may become the penetration path of the plating solution inside the chip, which is closely related to the moisture resistance reliability.

[0085] Taking a specific example, the alkali oxide is Li 2 O 3 and Na 2 O 3 and can contain one or more of them.

[0086] The interface plating layers 141 and 142 are disposed at the ends of the internal electrodes 121 and 122 and can play a role in improving the electrical connectivity between the internal electrodes 121 and 122 and the external electrodes 131 and 132. In addition, it can play a role in suppressing the oxidation of the ends of the internal electrodes 121 and 122 by the glass contained in the electrode layers 131a and 132a, thereby improving the connectivity between the internal electrode and the external electrode. Further, it can play a role in preventing the metal components of the electrode layers 131a and 132a from diffusing into the internal electrodes 121 and 122 and suppressing the radiation cracks due to the volume expansion of the internal electrodes.

[0087] The interface plating layers 141 and 142 can include a first interface plating layer 141 disposed at the end of the first internal electrode 121 and a second interface plating layer 142 disposed at the end of the second internal electrode 122.

[0088] In one embodiment, the main body 110 includes groove portions G1 and G2 where the ends of the internal electrodes 121 and 122 are spaced apart from one surface of the main body 110, and the interface plating layers 141 and 142 can include a first region disposed in the groove portions G1 and G2 and a second region protruding on one surface of the main body.

[0089] The groove portions G1 and G2 can be formed by the difference in the shrinkage behavior between the internal electrodes 121 and 122 and the dielectric layer 111 during the firing process of the main body 110. When the firing shrinkage rate of the internal electrodes 121 and 122 is larger than that of the dielectric layer 111, there may be a problem that the connectivity between the internal electrodes 121 and 122 and the external electrodes 131 and 132 is reduced by the groove portions G1 and G2. Conventionally, in order to solve such a problem, a process of removing the protruding dielectric layer using a sandblasting method or the like was added to solve such a problem. On the other hand, according to one embodiment of the present invention, since the interface plating layers 141 and 142 include a first region disposed in the groove portions G1 and G2 and a second region protruding on one surface of the main body, the connectivity between the internal electrodes 121 and 122 and the external electrodes 131 and 132 can be improved without a separate polishing process.

[0090] In one embodiment, in the cross sections of the stacked electronic component 100 in the first direction and the second direction, the second region can have a semi-circular shape. In this case, while minimizing the interface plating layers 141 and 142, the effect of improving the connectivity between the internal electrodes 121 and 122 and the external electrodes 131 and 132 of the present invention can be ensured.

[0091] At this time, when the average thickness of the internal electrode is te, the average thickness of the dielectric layer is td, and the radius of the semi-circular shape is tr, te / 2 ≤ tr ≤ (te + td) / 2 can be satisfied. When the radius tr of the semi-circular shape is less than te / 2, the effect of improving the connectivity between the external electrode and the internal electrode is insufficient, and when it exceeds (te + td) / 2, the interface plating layers 141 and 142 can be connected to form a single layer.

[0092] The radius tr of the above semi-circular shape does not particularly need to be limited to a specific numerical value, and can be, for example, 0.05 to 4 μm.

[0093] The radius tr of the semi-circular shape can be measured by scanning the cross-sections of the main body 110 in the first direction and the second direction with a scanning electron microscope (SEM) at a magnification of 10,000 times. Also, the radius tr of the semi-circular shape can be measured at any five interface electrode layers 141 and 142, and the average value thereof can be taken as the radius tr of the semi-circular shape.

[0094] However, it is not necessary to limit the second region of the interface plating layers 141 and 142 to a semi-circular shape. As shown in FIGS. 7 and 8, the second regions of the interface plating layers 141' and 142' in the cross-sections of the laminated electronic component 100 according to a modification of the present invention in the first direction and the second direction can have a layer shape. In this way, when the second regions of the interface plating layers 141' and 142' are in a layer shape, the exposed portions of the internal electrodes can be more reliably covered, so that the effect of improving the connectivity between the internal electrodes 121 and 122 and the external electrodes 131 and 132 of the present invention can be more reliably ensured. At this time, the interface plating layers 141' and 142' can be arranged throughout the space between the extension line E1 of the first surface and the extension line E2 of the second surface.

[0095] At this time, the average thickness to of the interface plating layers 141' and 142' having a layer shape does not particularly need to be limited, and can be, for example, 1 to 10 μm, and more preferably 1 to 4 μm.

[0096] Here, the average thickness to of the interface plating layers 141' and 142' having a layer shape can mean the average thickness of the second region excluding the first region disposed inside the main body.

[0097] Also, referring to FIG. 9, the first interface plating layer 141'' can cover a part of the third surface 3, and the second interface plating layer 142'' can cover a part of the fourth surface 4. That is, at this time, the interface plating layers 141', 142' can be disposed in a part between the extension line E1 of the first surface and the extension line E2 of the second surface. In this case, the interface plating layers 141'', 142'' can be efficiently disposed to ensure the effect of improving the connectivity between the internal electrodes 121, 122 and the external electrodes 131, 132.

[0098] Also, referring to FIG. 10, the first interface plating layer 141''' covers the third surface 3, the second interface plating layer 142''' covers the fourth surface 4, and the first interface plating layer 141''' and the second interface plating layer 142''' can be extended and disposed on a part of the first surface 1 and the second surface 2. In this case, by extending the interface plating layers 141''', 142''' on a part of the first surface 1 and the second surface 2, the corners of the main body are covered, and it is easy to sufficiently ensure the thickness of the external electrodes at the corners of the main body, and the moisture resistance reliability can be improved.

[0099] In one embodiment, the interface plating layers 141, 142 can have an amorphous structure. A crystalline structure means a structure having a long-range periodicity in a three-dimensional lattice structure and capable of expressing the lattice structure using symmetry elements such as translation, rotation, reflection, and inversion. On the other hand, an amorphous structure can be meant to have no long-range periodicity but have a repeating structure in a short-range order with the atomic structures as basic units being connected.

[0100] By the interface plating layers 141, 142 having an amorphous structure, the diffusion of the glass and metal components of the external electrodes 131, 132 into the internal electrodes 121, 122 can be more effectively suppressed.

[0101] In one embodiment, the interface plating layers 141 and 142 can contain Ni and P. Thereby, it is possible to easily control the interface plating layers 141 and 142 to have an amorphous structure, and it is possible to easily suppress the diffusion of the glass and metal components of the external electrode into the internal electrode.

[0102] At this time, the mass ratio of the P content to the Ni content contained in the interface plating layers 141 and 142 can be 8% or more and 15% or less. When the mass ratio of the P content to the Ni content contained in the interface plating layers 141 and 142 exceeds 15%, the equivalent series resistance (ESR) between the internal electrode and the external electrode may increase. When it is less than 8%, as the coefficient of thermal expansion of the interface plating layers 141 and 142 increases, the difference in the coefficient of thermal expansion from the main body at high temperature may increase, and thereby the bonding force between the interface plating layer and the main body may become weak.

[0103] In one embodiment, the interface plating layers 141 and 142 can contain Ni and B. Thereby, it is possible to easily control the interface plating layers 141 and 142 to have an amorphous structure, and it is possible to easily suppress the diffusion of the glass and metal components of the external electrode into the internal electrode.

[0104] At this time, the mass ratio of the B content to the Ni content contained in the interface plating layers 141 and 142 can be 2.5% or more and 10% or less. Thereby, it is possible to increase the resistance of charge transfer in the interface plating layers 141 and 142 and improve the corrosion resistance due to exposure to moisture from the outside, water penetration, etc.

[0105] On the other hand, the analysis of the elements contained in the interface plating layers 141 and 142 can be measured by using a scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS) for cross-sections in the first and second directions passing through the center in the third direction of the main body 110. After measuring the content of each element at the center of five or more interface plating layers 141 and 142 using EDS and obtaining the average value of each element, the mass ratio of the P content to the Ni content or the mass ratio of the B content to the Ni content can be obtained using the above average value.

[0106] The external electrodes 131 and 132 can include plating layers 131b and 132b disposed on the electrode layers 131a and 132a.

[0107] The plating layers 131b and 132b play a role in improving the mounting characteristics. The types of the plating layers 131b and 132b are not particularly limited, and can be plating layers containing one or more of Ni, Sn, Pd, and their alloys, and can be formed of multiple layers.

[0108] To give a more specific example of the plating layers 131b and 132b, the plating layers 131b and 132b can be Ni plating layers or Sn plating layers, and can be in a form where a Ni plating layer and an Sn plating layer are sequentially formed on the electrode layers 131a and 132a, and can be in a form where an Sn plating layer, a Ni plating layer, and an Sn plating layer are sequentially formed. Also, the plating layers 131b and 132b can include multiple Ni plating layers and / or multiple Sn plating layers.

[0109] 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, 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 technical field, and it can be said that these also belong to the scope of the present invention.

[0110] Also, 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 the matter described in a specific one embodiment is not described in other one embodiments, it can be understood as an explanation related to other one embodiments as long as there is no explanation contrary to or conflicting with that matter in other one embodiments.

[0111] 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 it clearly means something different in the context.

Explanation of Reference Numerals

[0112] 100 Multilayer Electronic Component 110 Body 111 Dielectric Layer 112, 113 Cover Portion 114, 115 Margin Portion 121, 122 Internal Electrode 131, 132 External Electrode 131a, 132a Electrode Layer 131b, 132b Plating Layer 141, 142 Interface Plating Layer

Claims

1. a body including dielectric layers and internal electrodes interleaved with the dielectric layers; an interface plating layer disposed on an end of the internal electrode; an external electrode disposed to cover the interface plating layer, the external electrode including glass containing Si and Al and an electrode layer including a conductive metal; the electrode layer includes an inner region adjacent to the interfacial plating layer and an outer region disposed on the inner region, and an area fraction of glass included in the inner region is higher than an area fraction of glass included in the outer region.

2. 2. The multilayer electronic component according to claim 1, wherein an area fraction of the glass contained in the inner region is at least three times a fraction of the glass contained in the outer region.

3. 2. The multilayer electronic component according to claim 1, wherein an area fraction of the glass included in the inner region is 80% or more, and an area fraction of the glass included in the outer region is 30% or less.

4. 2. The multilayer electronic component according to claim 1, wherein the inner region has an area fraction of glass of 80% or more within 1 μm from the interface with the interface plating layer.

5. 2. The multilayer electronic component according to claim 1, wherein the average thickness of the inner region is not less than 1 μm and not more than 5 μm.

6. The laminated electronic component according to claim 1 , wherein the glass further contains Fe.

7. The glass is SiO ２ , Al ２ O ３ and Fe ２ O ３ The multilayer electronic component according to claim 6 .

8. The laminated electronic component according to claim 1 , wherein the glass further contains an alkali oxide.

9. The alkali oxide is Li ２ O ３ and Na ２ O ３ The laminated electronic component according to claim 8 , comprising one or more of the following:

10. The multilayer electronic component according to claim 1 , wherein the interface plating layer has an amorphous structure.

11. The multilayer electronic component according to claim 1 , wherein the interface plating layer contains at least one of P and B, and Ni.

12. 2. The multilayer electronic component according to claim 1, wherein the interface plating layer contains Ni and P, and a mass ratio of the P content to the Ni content contained in the interface plating layer is 8% or more and 15% or less.

13. 2. The multilayer electronic component according to claim 1, wherein the interface plating layer contains Ni and B, and a mass ratio of the B content to the Ni content contained in the interface plating layer is 2.5% or more and 10% or less.

14. the body includes a groove in which an end of the internal electrode is spaced from one surface of the body, The multilayer electronic component according to claim 1 , wherein the interface plating layer includes a first region disposed in the groove and a second region protruding above one surface of the main body.

15. the internal electrodes and the dielectric layers are alternately disposed in a first direction, and the body includes first and second surfaces facing each other in the first direction, third and fourth surfaces connected to the first and second surfaces and facing each other in the second direction, and fifth and sixth surfaces connected to the first, second, third and fourth surfaces and facing each other in the third direction, The multilayer electronic component according to claim 14 , wherein the second region has a semicircular shape in cross sections of the multilayer electronic component in the first and second directions.

16. the internal electrodes and the dielectric layers are alternately disposed in a first direction, and the body includes first and second surfaces facing each other in the first direction, third and fourth surfaces connected to the first and second surfaces and facing each other in the second direction, and fifth and sixth surfaces connected to the first, second, third, fourth, and fourth surfaces and facing each other in the third direction, The multilayer electronic component according to claim 14 , wherein the second region in the cross sections of the multilayer electronic component in the first and second directions has a layered shape.

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