Multilayer electronic component

Abstract

The present disclosure provides a multilayer electronic component. The multilayer electronic component includes: a body including dielectric layers and internal electrodes alternately disposed with the dielectric layers; the interface plating layer is arranged at one end, close to the outer surface of the main body, of the inner electrode; and an external electrode disposed to cover the interface plating layer and a portion of the external surface of the body where the interface plating layer is not disposed, and the external electrode includes an electrode layer including a glass including 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 an area fraction of the glass included in the inner region may be higher than an area fraction of the glass included in the outer region.

Description

[0001] This application claims the benefit of priority of Korean Patent Application No. 10-2023-0161318, filed with the Korean Intellectual Property Office on November 20, 2023, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0002] The present disclosure relates to a multi-layer electronic component. Background Art

[0003] A multi-layer ceramic capacitor (MLCC), a type of multi-layer electronic component, is a chip capacitor mounted on a printed circuit board of any one of various electronic products such as imaging devices including a liquid crystal display (LCD) or a plasma display panel (PDP), a computer, a smartphone, or a mobile phone, for charging or discharging therefrom.

[0004] The multi-layer ceramic capacitor has a small size, enables high capacitance, and is easily mounted on a board, and thus can be used as a component of various electronic devices.

[0005] Recently, as electronic devices have smaller sizes and higher performance, multi-layer ceramic capacitors also tend to be miniaturized and have higher capacitance. Accordingly, the importance of ensuring high reliability of multi-layer ceramic capacitors is increasing.

[0006] To miniaturize such multi-layer ceramic capacitors, there is a trend of reducing the thickness of the external electrodes, and even when the thickness of the external electrodes is reduced, a method for ensuring reliability in a high-temperature and high-humidity environment is required. Summary of the Invention

[0007] One aspect of the present disclosure is to provide a multi-layer electronic component having excellent reliability.

[0008] One aspect of the present disclosure is to improve the electrical connectivity between an internal electrode and an external electrode.

[0009] One aspect of the present disclosure is to improve the capacitance per unit volume of the multi-layer electronic component.

[0010] However, the object of the present disclosure is not limited to the above, and will be more easily understood in the process of explaining specific embodiments of the present disclosure.

[0011] According to one aspect of the present disclosure, a multi-layer electronic component may include: a body including a dielectric layer and inner electrodes alternately disposed with the dielectric layer; an interface plating layer disposed at one end of the inner electrode close to the outer surface of the body; and an outer electrode disposed to cover the interface plating layer and a portion of the outer surface of the body where the interface plating layer is not provided, and the outer electrode includes an electrode layer, the electrode layer includes a glass containing Si and Al and a conductive metal, wherein the electrode layer includes an inner region adjacent to the interface plating layer and an outer region disposed on the inner region, and an area fraction of the glass included in the inner region may be higher than an area fraction of the glass included in the outer region. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The above and other aspects, features, and advantages of the present disclosure will be more clearly understood from the following specific embodiments in conjunction with the accompanying drawings.

[0013] Figure 1 A perspective view of a multi-layer electronic component according to an embodiment of the present disclosure is schematically shown.

[0014] Figure 2 Schematically shown is a cross-sectional view taken along Figure 1 line I-I'.

[0015] Figure 3 Schematically shown is a cross-sectional view taken along Figure 1 line II-II'.

[0016] Figure 4 Schematically shown is the body in a disassembled state.

[0017] Figure 5 Schematically shown is Figure 2 a part of the body.

[0018] Figure 6 is an enlarged view showing Figure 2 region K1.

[0019] Figure 7 is a diagram corresponding to Figure 2 according to a modified example of the present disclosure.

[0020] Figure 8 is an enlarged view showing Figure 7 region K2.

[0021] Figure 9 is a diagram corresponding to Figure 2 according to another modified example of the present disclosure.

[0022] Figure 10 is a diagram corresponding to Figure 2Corresponding figure.

[0023] Figure 11 is an image of a cross-section of a multilayer electronic component scanned by a scanning electron microscope in a first direction and a second direction according to an embodiment of the present disclosure.

[0024] Figure 12 is an image of a cross-section of a multilayer electronic component scanned by a scanning electron microscope in a first direction and a second direction according to a modified example of the present disclosure. Detailed implementation manners

[0025] Hereinafter, some embodiments of the present disclosure will be described with reference to the accompanying drawings. However, the present disclosure can be illustrated in many different forms and should not be construed as limited to the specific embodiments set forth herein. Rather, these embodiments are provided so that the present disclosure will be thorough and complete, and the scope of the present disclosure will be fully conveyed to those skilled in the art. Therefore, for the sake of clear description, the shapes and sizes of the elements in the drawings may be exaggerated, and the elements indicated by the same reference numerals in the drawings are the same elements.

[0026] In the drawings, irrelevant descriptions will be omitted to clearly describe the present disclosure, and for the sake of clearly expressing multiple layers and regions, the thickness may be enlarged. The same reference numerals will be used to describe the same elements having the same functions within the scope of the same concept. Throughout the specification, unless otherwise specifically stated, when an element is referred to as "including" or "comprising" a component, it means that it may further include other components without excluding other components.

[0027] In the drawings, the first direction may refer to the stacking direction or the thickness direction, the second direction may refer to the length direction, and the third direction may refer to the width direction.

[0028] Multi-layer electronic component Figure 1 A perspective view of a multilayer electronic component according to an embodiment of the present disclosure is schematically shown.

[0029] Figure 2 is schematically shown along Figure 1 a cross-sectional view taken along line I-I'.

[0030] Figure 3 is schematically shown along Figure 1 a cross-sectional view taken along line II-II'.

[0031] Figure 4 A perspective view of the body in a disassembled state is schematically shown.

[0032] Figure 5 is schematically shown Figure 2 a part of the body.

[0033] Figure 6 is a magnified view of the region K1 shown Figure 2 thereof.

[0034] Hereinafter, reference will be made to Figures 1 to 6 describe in detail a multilayer electronic component 100 according to an embodiment of the present disclosure. A multilayer ceramic capacitor will be described as an example of the multilayer electronic component, but the present disclosure is not limited thereto, and the present disclosure can also be applied to various multilayer electronic components using ceramic materials, such as inductors, piezoelectric elements, varistors, thermistors, etc.

[0035] According to some embodiments of the present disclosure, the multilayer electronic component 100 may include: a main body 110 including a dielectric layer 111 and inner electrodes 121 and 122 alternately disposed with the dielectric layer 111; interface plating layers 141 and 142 disposed at ends of the inner electrodes (e.g., one end close to the outer surface of the main body 110); and outer electrodes 131 and 132 disposed to cover the interface plating layers 141 and 142 and including electrode layers 131a and 132a, the electrode layer 131a including a glass GL1 containing Si and Al and a conductive metal M1, the electrode layer 132a including a glass GL2 containing Si and Al and a conductive metal M2, wherein the electrode layer may include an inner region adjacent to the interface plating layer and an outer region disposed on the inner region, and an area fraction of the glass included in the inner region may be higher than an area fraction of the glass included in the outer region.

[0036] In order to miniaturize the multilayer ceramic capacitor, there is a tendency to reduce the thickness of the outer electrode, and even when the thickness of the outer electrode is reduced, a method for ensuring reliability in a high-temperature and high-humidity environment is required.

[0037] Therefore, a method of changing the glass component included in the electrode layer to a glass containing Si and Al has been considered, and the glass containing Si and Al is a plating-resistant glass that effectively improves reliability by preventing the penetration of plating solutions, moisture, etc.

[0038] When the glass containing Si and Al is applied to the electrode layer, deterioration of reliability due to the penetration of plating solutions, moisture, etc. can be prevented. However, when the electrode layer is sintered, the glass containing Si and Al moves toward its interface with the main body, and oxidation occurs at the end of the inner electrode, thereby possibly causing a problem of deterioration in connectivity between the inner electrode and the outer electrode.

[0039] According to some embodiments of the present disclosure, a glass containing Si and Al may be included in the electrode layer, and an interface plating layer may be provided at the end of the inner electrode. Therefore, oxidation at the end of the inner electrode can be suppressed, thereby improving reliability and improving connectivity between the inner electrode and the outer electrode.

[0040] In the following, each component included in the multi-layer electronic component 100 according to some embodiments of the present disclosure will be described.

[0041] The body 110 has dielectric layers 111 and internal electrodes 121 and 122 stacked alternately therein.

[0042] The body 110 is not limited to a specific shape and may have a hexahedral shape or a shape similar to a hexahedral shape, as Figures 1 to 4 shown. Since the ceramic powder included in the body 110 shrinks during the process of sintering the body, the body 110 may not have a hexahedral shape including perfect straight lines. However, the body 110 may generally have a hexahedral shape.

[0043] The body 110 may have a first surface 1 and a second surface 2 opposite to 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 opposite to 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 opposite to each other in a third direction.

[0044] Since the edge regions of the dielectric layer 111 where the internal electrodes 121 and 122 are not provided are stacked in the first direction, a step difference may be formed due to the thickness of the internal electrodes 121 and 122, such that when observed with respect to the first surface or the second surface, the corners connecting the first surface to the third surface to the sixth surface and / or the corners connecting the second surface to the third surface to the sixth surface may have a shape that contracts toward the center of the body 110 in the first direction. Alternatively, due to the shrinkage behavior during the sintering process of the body, when observed with respect to the first surface or the second surface, the corners connecting the first surface 1 to the third surface 3, the fourth surface 4, the fifth surface 5, and the sixth surface 6 and / or the corners connecting the second surface 2 to the third surface 3, the fourth surface 4, the fifth surface 5, and the sixth surface 6 may have a shape that contracts toward the center of the body 110 in the first direction. Alternatively, since the edges connecting the corresponding surfaces of the body 110 to each other are rounded by performing an additional process to prevent chipping defects, etc., the corners connecting the first surface to the third surface to the sixth surface and / or the corners connecting the second surface to the third surface to the sixth surface may have a rounded shape.

[0045] In addition, in order to suppress the step difference formed by the inner electrodes 121 and 122, after stacking, cutting is performed such that the inner electrodes are exposed on two side surfaces of the capacitance forming portion Ac in the third direction (width direction). Then, the edge portions 114 and 115 are formed by stacking a single dielectric layer or two or more dielectric layers on the two side surfaces of the capacitance forming portion Ac in the third direction (width direction). In this case, the corners connecting the first surface to the fifth and sixth surfaces and the corners connecting the second surface to the fifth and sixth surfaces may not have the above-described contracted form.

[0046] The plurality of dielectric layers 111 forming the main body 110 may be in a sintered state, and adjacent dielectric layers 111 may be integrated with each other such that their boundaries may not be easily distinguishable without using a scanning electron microscope (SEM). The number of stacked dielectric layers is not particularly limited and may be determined in consideration of the size of the multilayer electronic component. For example, the main body may be formed by stacking 400 or more dielectric layers.

[0047] The dielectric layer 111 may be formed by the following method: preparing a ceramic slurry containing ceramic powder, an organic solvent, and a binder, coating the slurry on a carrier film and drying it to prepare a ceramic green sheet, and then sintering the ceramic green sheet. The ceramic powder is not particularly limited as long as sufficient electrostatic capacitance can be obtained therefrom. However, for example, barium titanate (BaTiO 3 )-based powder can be used as the ceramic powder. For a more specific example, the ceramic powder may be at least one selected from the group consisting 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).

[0048] The average thickness td of the dielectric layer 111 is not particularly limited. For example, the average thickness td of the dielectric layer 111 may be from 0.01 μm to 10 μm. In addition, the average thickness td of the dielectric layer 111 can be arbitrarily set according to desired characteristics or purposes. For example, in the case of small information technology (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 may be less than or equal to 0.4 μm.

[0049] Here, the average thickness td of the dielectric layer 111 may mean the average dimension in the first direction of the dielectric layer 111 disposed between adjacent inner electrodes 121 and 122. The average thickness td of the dielectric layer 111 can be obtained by scanning a cross-section of the main body 110 in the first and second directions with a scanning electron microscope (SEM) at a magnification of 10,000. More specifically, the average thickness td can be obtained by measuring the thicknesses at a plurality of points (e.g., 30 equally spaced points) in the second direction of one dielectric layer 111 and averaging them. The 30 equally spaced points can be specified in the capacitance forming portion Ac to be described later. In addition, if the average thickness measurement is extended to 10 dielectric layers 111 to obtain an average value, the average thickness of the dielectric layer 111 can be made more general.

[0050] The main body 110 may include: a capacitance forming portion Ac, disposed in the main body 110 and forming a capacitance by including a first inner electrode 121 and a second inner electrode 122 arranged to face each other with the dielectric layer 111 interposed therebetween; and covering portions 112 and 113, formed above and below the capacitance forming portion Ac in the first direction.

[0051] In addition, 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 stacking a plurality of first inner electrodes 121 and a plurality of second inner electrodes 122 with the dielectric layer 111 interposed therebetween.

[0052] The covering portions 112 and 113 may include an upper covering portion 112 disposed above the capacitance forming portion Ac in the first direction, and a lower covering portion 113 disposed below the capacitance forming portion Ac in the first direction.

[0053] The upper covering portion 112 and the lower covering portion 113 can be formed by stacking a single dielectric layer or two or more dielectric layers on the upper surface and the lower surface in the thickness direction of the capacitance forming portion Ac, respectively, and the upper covering portion 112 and the lower covering portion 113 can be mainly used to prevent damage to the inner electrodes due to physical stress or chemical stress.

[0054] The upper covering portion 112 and the lower covering portion 113 do not include inner electrodes and may include the same material as that of the dielectric layer 111.

[0055] That is, the upper covering portion 112 and the lower covering portion 113 may include a ceramic material, for example, a barium titanate (BaTiO 3 )-based ceramic material.

[0056] In addition, the thicknesses of the covering portions 112 and 113 are not particularly limited. However, in order to more easily achieve miniaturization and high capacitance of the multilayer electronic component, the average thickness tc of the covering portions 112 and 113 may be less than or equal to 15 μm.

[0057] The average thickness tc of the covering portions 112 and 113 may mean their dimensions in the first direction, and may be a value obtained by averaging the dimensions in the first direction of the covering portions 112 and 113 measured at five points having equal intervals in the second direction or the third direction above or below the capacitance forming portion Ac.

[0058] In addition, the edge portions 114 and 115 may be provided on two side surfaces of the capacitance forming portion Ac in the third direction (width direction).

[0059] The edge portions 114 and 115 may include a first edge portion 114 provided on one side surface of the capacitance forming portion Ac in the third direction (width direction) and a second edge portion 115 provided on the other side surface of the capacitance forming portion Ac in the third direction (width direction). That is, the edge portions 114 and 115 may be provided on two side surfaces of the capacitance forming portion Ac in the third direction (width direction).

[0060] As Figure 3 shown, the edge portions 114 and 115 may mean the regions between the two ends in the width direction of the first inner electrode 121 and the second inner electrode 122 and the outer surface of the main body 110 in the width direction in a cross section of the main body 110 taken along the width direction - thickness direction.

[0061] The edge portions 114 and 115 may mainly be used to prevent damage to the inner electrodes caused by physical stress or chemical stress.

[0062] The edge portions 114 and 115 may be formed by the following method: applying a conductive paste to a region of the ceramic green sheet other than the region where the edge portions are to be formed to form the inner electrodes.

[0063] In addition, in order to suppress the step difference formed by the inner electrodes 121 and 122, after stacking, cutting is performed so that the inner electrodes are exposed on two side surfaces of the capacitance forming portion Ac in the third direction (width direction), and then, the edge portions 114 and 115 may be formed by stacking a single dielectric layer or two or more dielectric layers on two side surfaces of the capacitance forming portion Ac in the third direction (width direction).

[0064] In addition, the widths of the edge portions 114 and 115 are not particularly limited. However, in order to more easily achieve miniaturization and high capacitance of the multilayer electronic component, the average widths of the edge portions 114 and 115 may be less than or equal to 15 μm.

[0065] The average widths of the edge portions 114 and 115 may mean the average sizes of the regions where the inner electrodes are spaced apart from the fifth surface and the sixth surface in the third direction, respectively, and may be values obtained by averaging the sizes of the edge portions 114 and 115 measured at five equally spaced points on the side surfaces of the capacitance forming portion Ac in the third direction.

[0066] Therefore, in some embodiments, the average sizes of the regions where the inner electrodes 121 and 122 are spaced apart from the fifth surface and the sixth surface in the third direction may be less than or equal to 15 μm, respectively.

[0067] In addition, when a magnetic material is applied to the main body 110 instead of the dielectric material, the multilayer electronic component 100 can be used as an inductor. The magnetic material may be, for example, ferrite particles and / or metal magnetic particles. When the multilayer electronic component is used as an inductor, the inner electrodes 121 and 122 can be coil-type conductors.

[0068] In addition, when a piezoelectric material is included in the main body 110 instead of the dielectric material, the multilayer electronic component 100 can be used as a piezoelectric element. The piezoelectric material may be, for example, lead zirconate titanate (PZT).

[0069] Furthermore, when a ZnO-based material or a SiC-based material is included in the main body 110 instead of the dielectric material, the multilayer electronic component 100 can be used as a varistor, and when a spinel-based material is included in the main body 110 instead of the dielectric material, the multilayer electronic component 100 can be used as a thermistor.

[0070] That is to say, in addition to the multilayer ceramic capacitor, the multilayer electronic component 100 according to some embodiments of the present disclosure can be used as an inductor, a piezoelectric element, a varistor, or a thermistor by appropriately changing the material or structure of the main body 110.

[0071] The inner electrodes 121 and 122 may be alternately arranged with the dielectric layer 111. For example, the first inner electrode 121 and the second inner electrode 122, which are a pair of electrodes with different polarities, may be arranged opposite to each other with the dielectric layer 111 interposed therebetween. The first inner electrode 121 and the second inner electrode 122 may be electrically separated from each other by the dielectric layer 111 provided therebetween. In this case, the inner electrodes 121 and 122 may be alternately arranged with the dielectric layer 111 in the first direction.

[0072] The first internal electrode 121 may be spaced apart from the fourth surface 4, but may extend to the third surface 3. The second internal electrode 122 may be spaced apart from the third surface 3, but may extend to the fourth surface 4. The first internal electrode 121 may be electrically connected to the first external electrode 131 on the third surface 3, and the second internal electrode 122 may be electrically connected to the second external electrode 132 on the fourth surface 4.

[0073] The conductive metal included in the internal electrodes 121 and 122 may be at least one selected from the group consisting of Ni, Cu, Pd, Ag, Au, Pt, Sn, W, Ti, and their alloys. More preferably, Ni may be included, but the present disclosure is not limited thereto.

[0074] The method for forming the internal electrodes 121 and 122 is not particularly limited. For example, the internal electrodes 121 and 122 may be formed by coating a conductive paste for internal electrodes containing a conductive metal on a green ceramic sheet and sintering them. The method of coating the conductive paste for internal electrodes may be a screen printing method or a gravure printing method, but the present disclosure is not limited thereto.

[0075] The average thickness te of the internal electrodes 121 and 122 is not particularly limited. For example, the average thickness te of the internal electrodes 121 and 122 may be 0.01 μm to 3 μm. In addition, the average thickness te of the internal electrodes 121 and 122 may be arbitrarily set according to desired characteristics or purposes. For example, in the case of a small IT electronic component, 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 may be less than or equal to 0.4 μm.

[0076] Here, the average thickness te of the internal electrode may be obtained 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. More specifically, the average thickness te may be obtained by measuring the thicknesses at a plurality of points (for example, 30 equally spaced points) in the second direction of one of the internal electrodes 121 and 122 and averaging them. The 30 equally spaced points may be specified in the capacitance forming portion Ac. In addition, if the average thickness measurement is extended to 10 internal electrodes 121 and 122 to obtain an average value, the average thickness of the internal electrodes 121 and 122 may be made more general.

[0077] The external electrodes 131 and 132 may be provided to cover the interface plating layers 141 and 142, and include electrode layers 131a and 132a. The electrode layer 131a includes a glass GL1 containing Si and Al and a conductive metal M1, and the electrode layer 132a includes a glass GL2 containing Si and Al and a conductive metal M2.

[0078] As Figure 2As shown in the figure, the outer electrodes 131 and 132 may include a first outer electrode 131 and a second outer electrode 132. The first outer electrode 131 is disposed on the third surface 3 of the main body 110 and is connected to the first inner electrode 121 through a first interface plating layer 141. The second outer electrode 132 is disposed on the fourth surface 4 of the main body 110 and is connected to the second inner electrode 122 through a second interface plating layer 142. The first outer electrode 131 may include a first electrode layer 131a, and the second outer electrode 132 may include a second electrode layer 132a.

[0079] In this embodiment, a structure in which the multilayer electronic component 100 has two outer electrodes 131 and 132 is described. However, the number and shape of the outer electrodes 131 and 132 may be changed according to the shape of the inner electrodes 121 and 122 or other purposes.

[0080] Figure 6 is a magnified view of Figure 2 region K1 shown.

[0081] Region K1 is shown by magnifying the portion where the first outer electrode 131 is provided. However, the structures of the first outer electrode 131 and the second outer electrode 132 are similar. Therefore, the following description will be provided based on the first outer electrode 131, but this is considered to include the description of the second outer electrode 132. The only difference is that the first outer electrode 131 is disposed on the third surface 3, and the second outer electrode 132 is disposed on the fourth surface 4. In addition, the electrode layer is described based on the first electrode layer 131a, but this is considered to include the description of the second electrode layer 132a. In addition, the interface plating layer is described based on the first interface plating layer 141, but this is considered to include the description of the second interface plating layer 142.

[0082] In the past, Ba-Zn-based glass containing Ba and Zn was used as the glass included in the electrode layer. However, since Ba-Zn-based glass is easily soluble in the plating solution, when using Ba-Zn-based glass, there may be a risk that the plating solution, moisture, etc. penetrate into the inner electrode. In addition, when the thickness of the electrode layer is thin, there may be a problem that the possibility of the plating solution, moisture, etc. penetrating into the inner electrode increases.

[0083] Therefore, in the present disclosure, an attempt is made to improve the moisture-proof reliability by including glasses GL1 and GL2 containing Si and Al (having excellent plating resistance compared to Ba-Zn-based glass) in the electrode layers 131a and 132a. Here, the glasses GL1 and GL2 containing Si and Al may refer to aluminosilicate-based glass.

[0084] The glasses GL1 and GL2 containing Si and Al have excellent plating resistance, but there are the following concerns: during the sintering process, the glass may move towards the interface between the electrode layer and the internal electrode and promote the formation of oxides at the ends of the internal electrodes, resulting in the oxidation of the ends of the internal electrodes. Therefore, when the glass included in the electrode layer is changed from Ba-Zn-based glass to the glasses GL1 and GL2 containing Si and Al, problems may occur that deteriorate the connectivity between the external electrode and the internal electrode.

[0085] Referring to Figure 6 , the first electrode layer 131a includes an internal region 131a1 adjacent to the first interface plating layer 141 and an external region 131a2 provided on the internal region 131a1, and the area fraction of the glass GL1 included in the internal region 131a1 (the area % obtained by dividing the area of the glass GL1 in the internal region 131a1 by the area of the internal region 131a1) is higher than the area fraction of the glass GL2 included in the external region 131a2 (the area % obtained by dividing the area of the glass GL2 in the external region 131a2 by the area of the external region 131a2). This is considered because the glasses GL1 and GL2 containing Si and Al have excellent wettability with the main body 110 and move towards the main body during the sintering process. As described above, when the area fraction of the glass GL1 included in the internal region 131a1 is higher than the area fraction of the glass GL2 included in the external region 131a2, the formation of oxides may be promoted at the ends of the internal electrodes, which may cause the oxidation at the ends of the internal electrodes. However, according to the present disclosure, the interface plating layers 141 and 142 may be provided at the ends of the internal electrodes 121 and 122 to prevent the oxidation of the ends of the internal electrodes.

[0086] That is, according to some embodiments of the present disclosure, the interface plating layers 141 and 142 may be provided at the ends of the internal electrodes 121 and 122 to suppress the oxidation of the ends of the internal electrodes 121 and 122, thereby improving the reliability and the connectivity between the internal electrodes and the external electrodes. In addition, even if the external electrodes 131 and 132 are formed thin, moisture-proof reliability can be ensured, and thus the capacitance per unit volume can be improved.

[0087] There is no particular limitation on the relationship between the area fractions of the glasses included in the internal region 131a1 and the external region 131a2 and their corresponding values.

[0088] According to some embodiments, the area fraction of the glass GL1 included in the internal region 131a1 may be greater than or equal to three times the area fraction of the glass GL2 included in the external region 131a2.

[0089] In addition, the area fraction of the glass GL1 included in the inner region 131a1 may be greater than or equal to 80%, greater than or equal to 85%, or greater than or equal to 90%, and the area fraction of the glass GL2 included in the outer region 131a2 may be less than or equal to 30%, less than or equal to 20%, or less than or equal to 10%.

[0090] The area fractions of the glass included in the inner region 131a1 and the outer region 131a2 can be obtained from the following image: an image of the first electrode layer 131a scanned using a scanning electron microscope (SEM) at a magnification of greater than or equal to 1500 times in a cross-section in the first and second directions of the multilayer electronic component 100 cut from the center of the main body 110 in the third direction. Refer to Figure 11 and Figure 12 , because there is a large contrast difference between the glass and the conductive metal in the image scanned by the SEM, the glass and the conductive metal can be clearly distinguished visually, and the area fraction can be obtained using an image analysis program. In addition, the metal of the first interface plating layer 141 and the metal of the first electrode layer 131a can be distinguished by performing elemental analysis using SEM-EDS.

[0091] Specifically, when the first interface plating layer 141 has a semicircular shape, by selecting a region of 10 μm × 2.5 μm (the size in the first direction × the size in the second direction) in a region within 5 μm outward from the main body 110 along the second direction and scanning it using SEM-EDS, and then using an image analysis program to measure the area of the glass (GLS1, unit: μm 2 ), and the area of the interface plating layer (PS, unit: μm 2 ), GLS1 / (25 μm 2 - PS) × 100 (%) can be used as the area fraction of the glass in the inner region 131a1. In addition, according to a modified example of the present disclosure, when the first interface plating layer 141' has a layered structure, a region of 10 μm × 2.5 μm (the size in the first direction × the size in the second direction) can be selected in a region within 5 μm outward from the first interface plating layer 141' along the second direction. However, when the average thickness of the inner region 131a1 is less than 2.5 μm, the measurement region can be set to have a size of 4 μm × 1 μm (the size in the first direction × the size in the second direction).

[0092] For the area fraction of the glass in the outer region 131a2, a region of 10 μm × 2.5 μm (the size in the first direction × the size in the second direction) can be selected in a region within 10 μm inward from the outer surface of the first electrode layer 131a along the second direction and scanned using SEM-EDS, and then an image analysis program can be used to measure the glass area (GLS2, unit: μm2 ), and GLS2 / 25μm can be 2 ×100 (%) as the area fraction of the glass in the outer region 131a2.

[0093] In addition, the area fraction of the conductive metal M1 included in the inner region 131a1 can be lower than the area fraction of the conductive metal M2 included in the outer region 131a2.

[0094] The average thickness of the inner region 131a1 can vary depending on sintering conditions, the type of interface plating, etc., but when applying general sintering conditions, the average thickness of the inner region 131a1 can be greater than or equal to 1 μm and less than or equal to 5 μm. The average thickness of the inner region 131a1 can be the average value of the values measured at 10 points at equal intervals in the first direction in the image scanned by SEM.

[0095] When applying general sintering conditions, the average thickness of the inner region 131a1 is greater than or equal to 1 μm. Therefore, in the region within 1 μm outward from the interface between the inner region 131a1 and the interface plating, the area fraction of the glass included in the inner region 131a1 can be greater than or equal to 80%.

[0096] In some embodiments, the glasses GL1 and GL2 may further include Fe. When the glasses GL1 and GL2 further contain Fe and there is no interface plating 141 and 142, the Fe contained in the glasses GL1 and GL2 may move toward the ends of the inner electrodes 121 and 122, so that Ni-Fe-O may be formed, and Ni-Fe-O may further promote the oxidation of the ends of the inner electrodes 121 and 122. Therefore, when the glasses GL1 and GL2 further include Fe, the effect of suppressing the oxidation at the ends of the inner electrodes 121 and 122 by providing the interface plating 141 and 142 according to the present disclosure may become more significant.

[0097] In some embodiments, the glasses GL1 and GL2 may include at least one selected from the group consisting of SiO 2 , Al 2 O 3 , and Fe 2 O 3 . Additionally, Si, Al, and Fe included in the glasses GL1 and GL2 may be included in the form of SiO 2 -Al 2 O 3 -Fe 2 O 3 .

[0098] In some embodiments, glasses GL1 and GL2 may also include alkaline oxides. The alkaline oxides can reduce the softening point by controlling the formation of oxygen bridges in glasses GL1 and GL2, thereby improving the density of the electrode layer. Here, the density of the electrode layer refers to the degree of porosity generated on the surface when voids formed due to the sintering of the conductive metal during the electrode sintering process cannot be filled by the glass softening behavior. When there is a density difference in the electrode layer, the pores may become a path for the plating solution to penetrate into the sheet, and thus are closely related to the moisture-proof reliability.

[0099] For a specific example, the alkaline oxide may include at least one of Li 2 O and Na 2 O.

[0100] Interface coatings 141 and 142 may be provided at the ends of the inner electrodes 121 and 122 to improve the electrical connectivity between the inner electrodes 121 and 122 and the outer electrodes 131 and 132. In addition, interface coatings 141 and 142 may inhibit the oxidation of the ends of the inner electrodes 121 and 122 due to the glass included in the electrode layers 131a and 132a, thereby improving the connectivity between the inner electrodes and the outer electrodes. In addition, interface coatings 141 and 142 may prevent the metal components of the electrode layers 131a and 132a from diffusing into the inner electrodes 121 and 122, thereby suppressing the radiation cracks caused by the volume expansion of the inner electrodes.

[0101] Interface coatings 141 and 142 may include a first interface coating 141 provided at the end of the first inner electrode 121 and a second interface coating 142 provided at the end of the second inner electrode 122.

[0102] In some embodiments, as Figure 5 shown, the main body 110 may include groove portions G1 and G2, in which the ends of the inner electrodes 121 and 122 are spaced apart from the third surface 3 and the fourth surface 4 of the main body 110, and the interface coatings 141 and 142 may include a first region provided in the groove portions G1 and G2 and a second region respectively protruding onto the third surface 3 and the fourth surface 4 of the main body 110.

[0103] The groove portions G1 and G2 may be formed during the sintering process of the main body 110 due to the difference in the shrinkage behavior between the inner electrodes 121 and 122 and the dielectric layer 111. When the sintering shrinkage rate of the inner electrodes 121 and 122 is greater than that of the dielectric layer 111, there may be a problem that the connectivity between the inner electrodes 121 and 122 and the outer electrodes 131 and 132 is reduced due to the groove portions G1 and G2. In the conventional technology, an attempt is made to solve this problem by increasing the process of removing the protruding dielectric layer using a sandblasting method or the like. On the other hand, according to some embodiments of the present disclosure, since the interface plating layers 141 and 142 include a first region provided in the groove portions G1 and G2 and a second region protruding onto the third surface 3 and the fourth surface 4 of the main body 110, the connectivity between the inner electrodes 121 and 122 and the outer electrodes 131 and 132 can be improved without a separate polishing process.

[0104] In some embodiments, in the cross-section of the multilayer electronic component 100 in the first direction and the second direction, the second region may have a semicircular shape. In this case, while minimizing the interface plating layers 141 and 142, the effect of improving the connectivity between the inner electrodes 121 and 122 and the outer electrodes 131 and 132 of the present disclosure can be ensured.

[0105] In this case, when the average thickness of the inner electrode is te, the average thickness of the dielectric layer is td, and the radius of the semicircular shape is tr, te / 2 ≤ tr ≤ (te + td) / 2 can be satisfied. When the radius tr of the semicircular shape is less than te / 2, the effect of improving the connectivity between the outer electrode and the inner electrode may be insufficient, and when the radius tr of the semicircular shape is greater than (te + td) / 2, the interface plating layers 141 and 142 may be connected to each other to form a single layer.

[0106] There is no need to specifically limit the specific value of the radius tr of the semicircular shape, and the radius tr of the semicircular shape can be, for example, 0.05 μm to 4 μm.

[0107] The radius tr of the semicircular shape can be obtained by scanning the cross-section of the multilayer electronic component 100 in the first direction and the second direction with a scanning electron microscope (SEM) at a magnification of 10,000. In addition, the radius tr of the semicircular shape can be measured at any five interface plating layers 141 and 142, and the average value can be used as the radius tr of the semicircular shape.

[0108] However, the second region of the interface plating layers 141 and 142 is not limited to a semicircular shape, and as Figure 7 and Figure 8As shown, according to a modified example of the present disclosure, in a cross-section of the multi-layer electronic component 100 in the first direction and the second direction, the second regions of the interface plating layers 141' and 142' may be layered. As described above, when the second regions of the interface plating layers 141' and 142' are layered, the exposed portions of the inner electrodes can be covered more reliably, and the effect of improving the connectivity between the inner electrodes 121 and 122 and the outer electrodes 131 and 132 can be ensured more reliably. In this case, the interface plating layers 141' and 142' may be completely disposed between the extension line E1 of the first surface 1 and the extension line E2 of the second surface 2. For example, the interface plating layers 141' and 142' may be disposed in the entire region between the extension line E1 of the first surface 1 and the extension line E2 of the second surface 2.

[0109] In this case, the average thickness to of the layered interface plating layers 141' and 142' does not need to be particularly limited and may be, for example, 1 μm to 10 μm, more preferably 1 μm to 4 μm.

[0110] Here, the average thickness to of the layered interface plating layers 141' and 142' may mean the average thickness of the second region except for the first region disposed inside the main body.

[0111] In addition, referring to Figure 9 , the first interface plating layer 141'' may cover a part of the third surface 3, and the second interface plating layer 142'' may cover a part of the fourth surface 4. That is, in this case, the interface plating layers 141'' and 142'' may be partially disposed between the extension line E1 of the first surface 1 and the extension line E2 of the second surface 2. In this case, the interface plating layers 141'' and 142'' can be effectively disposed, so that the effect of improving the connectivity between the inner electrodes 121 and 122 and the outer electrodes 131 and 132 can be ensured.

[0112] In addition, referring to Figure 10 , the first interface plating layer 141''' may cover the third surface 3, the second interface plating layer 142''' may cover the fourth surface 4, and the first interface plating layer 141''' and the second interface plating layer 142''' may also extend on a part of the first surface 1 and a part of the second surface 2. In this case, when the interface plating layers 141''' and 142''' extend onto a part of the first surface 1 and a part of the second surface 2, the interface plating layers 141''' and 142''' may cover the edge of the main body 110, making it easy to ensure that the thickness of the outer electrodes 131 and 132 is sufficient at the edge of the main body 110, thereby improving the moisture-proof reliability.

[0113] In some embodiments, the interface coatings 141 and 142 may have an amorphous structure. A crystalline structure may mean a structure having a three-dimensional lattice structure with long-range periodicity. Thus, a crystalline structure means a structure in which the lattice structure can be expressed using symmetry elements such as translation, rotation, reflection, inversion, etc. On the other hand, an amorphous structure does not have long-range periodicity but may mean a repeating structure in which the atomic structures that are the basic units are connected and have short-range order.

[0114] Since the interface coatings 141 and 142 have an amorphous structure, the glass and metal components of the outer electrodes 131 and 132 can be more effectively prevented from diffusing into the inner electrodes 121 and 122.

[0115] In some embodiments, the interface coatings 141 and 142 may include one or more of P and B and Ni.

[0116] In some embodiments, the interface coatings 141 and 142 may include Ni and / or P. Thus, the interface coatings 141 and 142 can be easily controlled to have an amorphous structure, and the glass and metal components of the outer electrodes can be easily inhibited from diffusing into the inner electrodes 121 and 122.

[0117] In some embodiments, the mass ratio of the P content to the Ni content included in the interface coatings 141 and 142 may be greater than or equal to 8% and less than or equal to 15%. When the mass ratio of the P content to the Ni content included in the interface coatings 141 and 142 exceeds 15%, there may be a risk of an increase in the equivalent series resistance (ESR) between the inner and outer electrodes, and when the mass ratio of the P content to the Ni content included in the interface coatings 141 and 142 is less than 8%, as the thermal expansion coefficient of the interface coatings 141 and 142 increases, the difference in the thermal expansion coefficient from that of the main body at high temperatures may increase. Therefore, there may be a risk of a weakening in the bonding strength between the interface coatings 141 and 142 and the main body 110.

[0118] In some embodiments, the interface coatings 141 and 142 may include Ni and / or B. Thus, the interface coatings 141 and 142 can be easily controlled to have an amorphous structure, and the glass and metal components of the outer electrodes can be easily inhibited from diffusing into the inner electrodes 121 and 122.

[0119] In some embodiments, the mass ratio of the B content to the Ni content included in the interface coatings 141 and 142 may be greater than or equal to 2.5% and less than or equal to 10%. Thus, the charge transfer resistance of the interface coatings 141 and 142 can be increased to improve the corrosion resistance when exposed to external moisture, moisture penetration, etc.

[0120] In addition, the analysis of the elements included in the interface coatings 141 and 142 is performed on images obtained by scanning a cross-section of the multilayer electronic component 100 in the first and second directions and passing through the center of the multilayer electronic component 100 in the third direction using a scanning electron microscope (SEM) and an energy dispersive X-ray spectrometer (EDS). The average content of each element can be obtained by measuring the content of each element in the central portion of five or more interface coatings 141 and 142 using EDS, and then 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 average value.

[0121] The outer electrodes 131 and 132 may include coatings 131b and 132b provided on the electrode layers 131a and 132a. The coatings 131b and 132b can be used to improve the mounting characteristics. The types of the coatings 131b and 132b are not particularly limited, and the coatings 131b and 132b can be coatings containing one or more selected from the group consisting of Ni, Sn, Pd, and their alloys, and can be formed of multiple layers. For more specific examples of the coatings 131b and 132b, the coatings 131b and 132b may include Ni coatings or Sn coatings, or may have a form in which Ni coatings and Sn coatings are sequentially formed on the electrode layers 131a and 132a, or may have a form in which Sn coatings, Ni coatings, and Sn coatings are sequentially formed on the electrode layers 131a and 132a. In addition, the coatings 131b and 132b may include multiple Ni coatings and / or multiple Sn coatings.

[0122] As described above, as one of the many effects of the present disclosure, the reliability of the multilayer electronic component can be improved by including glass containing Si and Al in the electrode layer and providing interface coatings at the ends of the inner electrodes.

[0123] As one of the many effects of the present disclosure, the electrical connectivity between the inner electrodes and the outer electrodes can be improved.

[0124] As one of the many effects of the present disclosure, the capacitance per unit volume of the multilayer electronic component can be improved.

[0125] Although the embodiments of the present disclosure have been described in detail above, the present disclosure is not limited to the above embodiments and the drawings, and is intended to be limited by the appended claims. Therefore, those skilled in the art can make various forms of substitutions, modifications, and changes within the scope of the technical spirit of the present disclosure described in the claims, and these substitutions, modifications, and changes also fall within the scope of the present disclosure.

[0126] In addition, the expressions "one embodiment" and "some embodiments" used in the present disclosure do not refer to the same embodiment, and are provided to emphasize and describe different unique features. However, the features of one embodiment presented above do not exclude the implementation in combination with the features of another embodiment. For example, unless there is a description that contradicts or is contrary to the matters in another embodiment, even if the matters described in a specific embodiment are not described in another embodiment, they can be understood as descriptions related to another embodiment.

[0127] The terms used in the present disclosure are only for describing one embodiment and are not intended to limit the present disclosure. In this case, unless the context clearly indicates otherwise, the singular meaning includes the plural meaning.

[0128] Although the embodiments have been shown and described above, it will be readily understood by those skilled in the art that modifications and variations can be made without departing from the scope of the present disclosure defined by the appended claims.

Claims

1. A multilayer electronic component comprising: A main body, comprising a dielectric layer and inner electrodes arranged alternately with the dielectric layer; an interface coating, disposed at one end of the inner electrode close to the outer surface of the body; as well as an external electrode, arranged to cover the interface coating and a portion of the outer surface of the body where the interface coating is not arranged, and the external electrode comprises an electrode layer, the electrode layer comprises glass containing Si and Al and a conductive metal, The electrode layer includes an inner region adjacent to the interface coating and an outer region disposed on the inner region, and an area fraction of the glass included in the inner region is higher than an area fraction of the glass included in the outer region.

2. The multilayer electronic component of claim 1, wherein: An area fraction of the glass included in the inner region is greater than or equal to three times an area fraction of the glass included in the outer region.

3. The multilayer electronic component of claim 1, wherein: An area fraction of the glass included in the inner region is greater than or equal to 80%, and an area fraction of the glass included in the outer region is less than or equal to 30%.

4. The multilayer electronic component of claim 1, wherein: In a region within 1 μm outward from an interface between the inner region and the interface plating layer, an area fraction of the glass included in the inner region is greater than or equal to 80%.

5. The multilayer electronic component of claim 1, wherein: The inner region has an average thickness of greater than or equal to 1 μm and less than or equal to 5 μm.

6. The multilayer electronic component of claim 1, wherein: The glass also includes Fe.

7. The multilayer electronic component of claim 6, wherein: The glass further includes at least one selected from the group consisting of SiO2, Al2O3 and Fe2O3.

8. The multilayer electronic component of claim 1, wherein: The glass also includes an alkali oxide.

9. The multilayer electronic component of claim 8, wherein: The basic oxide includes one or more of Li2O and Na2O.

10. The multilayer electronic component of claim 1, wherein: The interface coating has an amorphous structure.

11. The multilayer electronic component of claim 1, wherein: The interface coating includes one or more of P and B and Ni.

12. The multilayer electronic component of claim 1, wherein: The interface plating layer includes Ni and P, and a mass ratio of a P content to a Ni content included in the interface plating layer is greater than or equal to 8% and less than or equal to 15%.

13. The multilayer electronic component of claim 1, wherein: The interface plating layer includes Ni and B, and a mass ratio of a content of B to a content of Ni included in the interface plating layer is greater than or equal to 2.5% and less than or equal to 10%.

14. The multilayer electronic component of claim 1, wherein: The body includes a groove portion in which the one end of the inner electrode is spaced apart from the outer surface of the body, and The interface plating layer includes a first region disposed in the groove portion and a second region protruding onto the outer surface of the body.

15. The multilayer electronic component of claim 14, wherein: The inner electrodes are alternately arranged with the dielectric layers in a first direction, and the body includes a first surface and a second surface opposite to each other in the first direction, a third surface and a fourth surface connected to the first surface and the second surface and opposite to each other in 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 opposite to each other in the third direction, and In cross sections of the multilayer electronic component in the first direction and the second direction, the second region has a semicircular shape.

16. The multilayer electronic component of claim 14, wherein: The inner electrodes are alternately arranged with the dielectric layers in a first direction, and the body includes a first surface and a second surface opposite to each other in the first direction, a third surface and a fourth surface connected to the first surface and the second surface and opposite to each other in 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 opposite to each other in the third direction, and In cross sections of the multilayer electronic component in the first direction and the second direction, the second region has a layer shape.

17. The multilayer electronic component of claim 16, wherein: The interface plating layer is disposed on the third surface and the fourth surface, respectively, and is disposed in an entire region between an extension line of the first surface and an extension line of the second surface.

18. The multilayer electronic component of claim 16, wherein: The interface plating layer is disposed on the third surface and the fourth surface, respectively, and is partially disposed between an extension line of the first surface and an extension line of the second surface.

19. The multilayer electronic assembly of claim 16, wherein: The interface plating layers are disposed on the third surface and the fourth surface, respectively, and extend onto a portion of the first surface and a portion of the second surface.

20. The multilayer electronic assembly of claim 1, wherein: An area fraction of the conductive metal included in the inner region is lower than an area fraction of the conductive metal included in the outer region.

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