Multilayer electronic component

Abstract

The present disclosure provides a multilayer electronic component including: a main body including a capacitance forming portion including a dielectric layer and internal electrodes alternately disposed with the dielectric layer in a first direction, and a cover portion covering the dielectric layer, covering portions provided on upper and lower portions of the capacitance forming portion in the first direction, respectively, and including a first surface and a second surface opposite to each other in the first direction; and an external electrode disposed on the main body. The covering portion includes one or more crystal phases including a compound of a rare earth element, Si, and O. When an area ratio occupied by the crystal phase in a central portion of at least one of the first surface and the second surface is defined as S1; and when the area ratio occupied by the crystal phase in a central portion of a cross-section in the first direction and the third direction of at least one of the covers is defined as S2, S1gt is satisfied; and S2.

Description

[0001] This application claims the priority of Korean Patent Application No. 10-2023-0197038, filed with the Korean Intellectual Property Office on December 29, 2023, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

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

[0003] A multi-layer ceramic component (MLCC, a type of multi-layer electronic component) can be a chip capacitor that is mounted on a printed circuit board of various electronic products (including image display devices such as liquid crystal displays (LCDs) and plasma display panels (PDPs), computers, smartphones, mobile phones, etc.) and charges or discharges electricity thereto.

[0004] Because multi-layer ceramic capacitors can have a small size and high capacitance and can be easily mounted, such multi-layer ceramic capacitors can be used as components of various electronic devices. As electronic devices such as computers and mobile devices have been designed to have a reduced size and higher output, the demand for miniaturization and higher capacitance of multi-layer ceramic capacitors has increased.

[0005] In addition, as the application of automotive electrical components increases, high reliability in various environments is necessary. In particular, since the powertrain, which is a core component of an automobile, may heat up to over 100 °C, it is necessary to develop a multi-layer ceramic capacitor that operates stably even at high temperatures.

[0006] To improve the high-temperature reliability of multi-layer ceramic capacitors, the material of the dielectric layer can be changed. For example, dielectric grains can be configured to have a core-shell structure. However, since the shape of the core-shell structure can greatly affect the electrical characteristics of multi-layer ceramic capacitors, it may be difficult to control the microstructure. Summary of the Invention

[0007] An embodiment of the present disclosure is to provide a multi-layer electronic component with improved reliability.

[0008] An embodiment of the present disclosure is to provide a multi-layer electronic component with improved high-temperature reliability.

[0009] According to an embodiment of the present disclosure, a multi-layer electronic component includes: a main body including a capacitance forming portion and a covering portion, the capacitance forming portion including a dielectric layer and inner electrodes alternately arranged with the dielectric layer in a first direction, the covering portion being provided on upper and lower portions of the capacitance forming portion in the first direction, and including a first surface and a second surface facing each other in the first direction, a third surface and a fourth surface connected to the first surface and the second surface and facing each other in a second direction, and a fifth surface and a sixth surface connected to the first surface, the second surface, the third surface, and the fourth surface and facing each other in a third direction; and an external electrode provided on the main body. The covering portion includes one or more crystal phases formed of a compound containing a rare earth element, Si, and O. When an area ratio occupied by the crystal phase in a central portion of at least one of the first surface and the second surface is defined as S1, and an area ratio occupied by the crystal phase in a central portion of a cross-section of at least one covering portion of the covering portion in the first direction and the third direction is defined as S2, S1 > S2 is satisfied. At least one of the first surface and the second surface is an outer surface of the covering portion. Description of the Drawings

[0010] The above and other aspects, features, and advantages of the present disclosure will be more clearly understood from the following detailed description in conjunction with the accompanying drawings, in which: Figure 1 is a perspective view showing a multi-layer electronic component according to an embodiment of the present disclosure; Figure 2 is along Figure 1 sectional view taken along line I-I' in Figure 3 is along Figure 1 sectional view taken along line II-II' in Figure 4 is a perspective view showing the Figure 1 main body in according to an embodiment of the present disclosure; Figure 5 is a scanning image of K1 obtained using a scanning electron microscope in Figure 1 ; Figure 6 is a scanning image of K2 obtained using a scanning electron microscope in Figure 3 ; Figure 7 is a view showing the shape of a crystal phase according to an embodiment of the present disclosure; and Figure 8 is a view showing a scanning image of the surface of a covering portion of a comparative example obtained using a scanning electron microscope. Detailed Description

[0011] In the following, embodiments of the present disclosure will be described with reference to the accompanying drawings as follows.

[0012] These embodiments are described in sufficient detail to enable those skilled in the art to practice the present invention. It should be understood that the various embodiments of the present invention, although different, are not necessarily mutually exclusive. For example, without departing from the spirit and scope of the present disclosure, the structures, shapes, and dimensions described as examples in the embodiments of the present disclosure can be implemented in another embodiment. In addition, without departing from the spirit and scope of the present disclosure, the position or arrangement of the elements in the embodiments can be modified. Therefore, the following detailed description should not be construed as limiting, and the scope of the present invention is defined only by the properly construed appended claims and the full scope of the equivalents given by the claims.

[0013] In the drawings, the same elements will be denoted by the same reference numerals. In addition, redundant descriptions and detailed descriptions of known functions and elements that may unnecessarily obscure the gist of the present disclosure will be omitted. In the drawings, some elements may be exaggerated, omitted, or shown briefly, and the dimensions of the elements do not necessarily reflect the actual dimensions of these elements. The terms "comprising", "including", "configured to", etc. in the specification are used to indicate the presence of features, quantities, steps, operations, elements, parts, or combinations thereof, and do not exclude the possibility of combining or adding one or more features, quantities, steps, operations, elements, parts, or combinations thereof.

[0014] In the drawings, the first direction may be defined as the thickness direction, the second direction may be defined as the length direction, and the third direction may be defined as the width direction.

[0015] Multi-layer electronic component Figure 1 is a perspective view showing a multilayer electronic component according to an embodiment.

[0016] Figure 2 is a sectional view taken along line I-I' in Figure 1 is a sectional view taken along line II-II' in

[0017] Figure 3 is a sectional view taken along line II-II' in Figure 1 is a sectional view taken along line II-II' in

[0018] Figure 4 is a perspective view showing a Figure 1 is an exploded view of the main body in

[0019] Figure 5 is a scanning image of K1 in Figure 1 obtained using a scanning electron microscope; Figure 6 is a scanning image ofFigure 3 A scanned image of K2 in Figure 7 is a view showing the shape of a crystal phase according to an embodiment of the present disclosure.

[0020] Hereinafter, reference will be made to Figures 1 to 7 Multilayer electronic component 100 according to an embodiment will be described in more detail. A multilayer ceramic capacitor (MLCC) will be described as an example of the multilayer electronic component, but the embodiments are not limited thereto, and the description of the multilayer ceramic capacitor can be applied to various multilayer electronic components such as inductors, piezoelectric elements, varistors, or thermistors.

[0021] The multilayer electronic component 100 may include: a main body 110 including a capacitance forming portion Ac and covering portions 112 and 113, the capacitance forming portion Ac including a dielectric layer 111 and internal electrodes 121 and 122 alternately disposed with the dielectric layer 111 in a first direction, the covering portions 112 and 113 being disposed on upper and lower portions of the capacitance forming portion Ac in the first direction, and the main body 110 including a first surface 1 and a second surface 2 opposite to each other in the 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 to the fourth surface 4 and opposite to each other in a third direction; and external electrodes 131 and 132 disposed on the main body 110. The covering portion may include one or more crystal phases (e.g., in the present application, "crystal phase" may refer to particles) formed of a compound containing a rare earth element, Si, and O. When the area ratio occupied by the crystal phase in the central portion of at least one of the first surface and the second surface (hereinafter simply referred to as "the first surface and the second surface") is defined as S1, and the area ratio occupied by the crystal phase in the central portion of the cross-section of at least one of the covering portions (hereinafter simply referred to as "the covering portion") in the first direction and the third direction is defined as S2, S1 > S2 may be satisfied.

[0022] According to an embodiment, by disposing the crystal phase 10a formed of a compound containing a rare earth element, Si, and O on the surfaces of the covering portions 112 and 113, the thermal conductivity can be reduced and the heat absorbed from the outside can be reduced, thereby improving the high-temperature reliability. In addition, the crystal phase 10a formed of a compound containing a rare earth element, Si, and O may have a relatively low coefficient of thermal expansion, so that cracks generated in the main body 110 can be prevented, and the moisture absorption rate can be reduced, thereby improving the moisture resistance reliability.

[0023] Hereinafter, each component included in the multilayer electronic component 100 according to an embodiment will be described.

[0024] In the main body 110, the dielectric layer 111 and the internal electrodes 121 and 122 may be alternately laminated.

[0025] The shape of the main body 110 is not limited to any specific shape. However, as shown in the figure, the main body 110 may have a hexahedron shape or a shape similar to a hexahedron shape. Due to the shrinkage of the ceramic particles included in the main body 110 or the polishing of the corners during the firing process, the main body 110 may not have an exact hexahedron shape formed by straight lines, but may have an approximately hexahedron shape.

[0026] The main body 110 may have a first surface 1 and a second surface 2 that are opposite to each other in a first direction, a third surface 3 and a fourth surface 4 that are connected to the first surface 1 and the second surface 2 and are opposite to each other in a second direction, and a fifth surface 5 and a sixth surface 6 that are connected to the first surface 1 and the second surface 2 and the third surface 3 and the fourth surface 4 and are opposite to each other in a third direction.

[0027] Since the edge regions of the inner electrodes 121 and 122 are not overlapped with the dielectric layer 111, a step difference may be formed due to the thickness of the inner electrodes 121 and 122. When observed from the first surface 1 or the second surface 2, 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 shrinks toward the center of the main body 110 in the first direction. Optionally, due to the shrinkage behavior of the main body 110 during the sintering process, when observed from the first surface 1 or the second surface 2, 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 shrinks toward the center of the main body 110 in the first direction. Optionally, in order to prevent cracking defects, the corners connecting the surfaces of the main body 110 may be rounded by performing a specific process to round the corners, so that each of 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 rounded shape.

[0028] In order to suppress the step difference formed by the inner electrodes 121 and 122, after laminating the dielectric layer 111 on which the inner electrode pattern is formed, the stacked body is cut so that the cut stacked body includes the capacitance forming portion Ac and the inner electrodes 121 and 122 are exposed to the two side surfaces of the capacitance forming portion Ac in the third direction. Then, a single dielectric layer or two or more dielectric layers are laminated on the two side surfaces of the cut stacked body in the third direction (width direction) to form the edge portions 114 and 115. The corners connecting the first surface 1 to the fifth surface 5 and the sixth surface 6 and the corners connecting the second surface 2 to the fifth surface 5 and the sixth surface 6 may not have a shrinking shape.

[0029] The plurality of dielectric layers 111 forming the main body 110 may be in a sintered state, and the adjacent dielectric layers 111 may be integrated with each other so that the boundary between them may not be easily distinguishable without using a scanning electron microscope (SEM). There is no specific limitation on the number of stacked dielectric layers 111, and the number of stacked layers can be determined by considering the size of the multilayer electronic component. For example, the main body 110 may be formed by laminating 400 or more layers of dielectric layers 111.

[0030] The dielectric layer 111 can be formed by the following method: preparing a ceramic slurry including ceramic powder, organic solvent, additive, and binder, preparing a ceramic green sheet by coating the slurry on a carrier film and drying the slurry, and firing the ceramic green sheet. The ceramic powder is not limited to any specific example as long as sufficient electrostatic capacitance can be obtained. For example, powders based on barium titanate (BaTiO3) and paraelectric powders based on CaZrO3 can be used as the ceramic powder. The powder based on barium titanate (BaTiO3) can be one or more of BaTiO3, (Ba 1-x Ca x )TiO3 (0 < x < 1), Ba(Ti 1-y Ca y )O3 (0 < y < 1), (Ba 1-x Ca x )(Ti 1-y Zr y )O3 (0 < x < 1, 0 < y < 1), and Ba(Ti 1-y Zr y )O3 (0 < y < 1). The paraelectric powder based on CaZrO3 can be (Ca 1-x Sr x )(Zr 1-y Ti y )O3 (0 < x < 1, 0 < y < 1).

[0031] Therefore, the dielectric layer 111 may include BaTiO3, (Ba 1-x Ca x)TiO3 (0 < x < 1), Ba(Ti 1-y Ca y )O3 (0 < y < 1), (Ba 1-x Ca x )(Ti 1-y Zr y )O3 (0 < x < 1, 0 < y < 1), Ba(Ti 1-y Zr y )O3 (0 < y < 1) and (Ca 1-x Sr x )(Zr 1-y Ti y )O3 (0 < x < 1, 0 < y < 1). In an embodiment, the dielectric layer 111 may include (Ca 1-x Sr x )(Zr 1-y Ti y )O3 (0 < x < 1, 0 < y < 1) as a main component.

[0032] The main body 110 may include a capacitor-forming portion Ac that forms a capacitor and covering portions 112 and 113. The capacitor-forming portion Ac includes a first inner electrode 121 and a second inner electrode 122 that are disposed in the main body 110 and face each other, and the dielectric layer 111 is located between the first inner electrode 121 and the second inner electrode 122. The covering portions 112 and 113 are formed on the upper and lower portions of the capacitor-forming portion Ac in a first direction.

[0033] In addition, the capacitor-forming portion Ac may contribute to forming the capacitance of the capacitor, and a plurality of first inner electrodes 121 and second inner electrodes 122 may be repeatedly stacked with the dielectric layer 111 interposed therebetween.

[0034] The inner electrodes 121 and 122 may include the first inner electrode 121 and the second inner electrode 122. The first inner electrode 121 and the second inner electrode 122 may be alternately disposed to face each other with the dielectric layer 111 therebetween, and may be respectively exposed to a third surface 3 and a fourth surface 4 of the main body 110.

[0035] The first inner electrode 121 may be spaced apart from the fourth surface 4 and may be exposed through the third surface 3. The second inner electrode 122 may be spaced apart from the third surface 3 and may be exposed through the fourth surface 4. The first outer electrode 131 may be disposed on the third surface 3 of the main body 110 and may be connected to the first inner electrode 121. The second outer electrode 132 may be disposed on the fourth surface 4 of the main body 110 and may be connected to the second inner electrode 122.

[0036] That is to say, the first inner electrode 121 may not be connected to the second outer electrode 132 and may be connected to the first outer electrode 131, and the second inner electrode 122 may not be connected to the first outer electrode 131 and may be connected to the second outer electrode 132. Accordingly, the first inner electrode 121 may be spaced apart from the fourth surface 4 by a predetermined distance, and the second inner electrode 122 may be spaced apart from the third surface 3 by a predetermined distance. In addition, the first inner electrode 121 and the second inner electrode 122 may be spaced apart from the fifth surface and the sixth surface of the main body 110.

[0037] The conductive metal included in the inner electrodes 121 and 122 may be one or more of Ni, Cu, Pd, Ag, Au, Pt, In, Sn, Al, Ti, and alloys thereof, but embodiments are not limited thereto.

[0038] The average thickness td of the dielectric layer 111 may not be limited to any specific example and may be, for example, 0.1 μm to 10 μm. The average thickness te of the inner electrodes 121 and 122 may not be limited to any specific example and may be, for example, 0.05 μm to 3.0 μm. In addition, the average thickness td of the dielectric layer 111 and the average thickness te of the inner electrodes 121 and 122 may be arbitrarily determined according to desired characteristics or applications. For example, in the case of a microelectronic component, in order to achieve miniaturization and high capacitance, the average thickness td of the dielectric layer 111 may be 0.4 μm or less, and the average thickness te of the inner electrodes 121 and 122 may be 0.4 μm or less.

[0039] The average thickness td of the dielectric layer 111 and the average thickness te of the inner electrodes 121 and 122 may respectively refer to the average dimensions in the first direction of the dielectric layer 111 and the inner electrodes 121 and 122. The average thickness td of the dielectric layer 111 and the average thickness te of the inner electrodes 121 and 122 may be measured by scanning a cross-section of the main body 110 in the first direction and the second direction at a magnification of 10,000 using a scanning electron microscope (SEM). More specifically, the average thickness of the dielectric layer 111 may be obtained by measuring the thicknesses in the first direction at a plurality of points (for example, 30 points at equal distances in the second direction) of the dielectric layer 111. In addition, the average thickness of the inner electrodes 121 and 122 may be obtained by measuring the thicknesses in the first direction at a plurality of points (for example, 30 points at equal distances in the second direction) of one of the inner electrodes 121 and 122. The 30 points at equal distances may be specified in the capacitance forming portion Ac. In addition, by measuring the average values of the thicknesses of 10 dielectric layers 111 and 10 inner electrodes 121 and 122, the average thickness of the dielectric layer 111 and the average thickness of the inner electrodes 121 and 122 may be further generalized.

[0040] The covering parts 112 and 113 may include an upper covering part 112 provided on the upper part of the capacitor forming part Ac in the first direction and a lower covering part 113 provided on the lower part of the capacitor forming part Ac in the first direction.

[0041] The upper covering part 112 and the lower covering part 113 may be formed by laminating a single dielectric layer or two or more dielectric layers on the upper surface and the lower surface of the capacitor forming part Ac in the thickness direction, respectively, and may substantially prevent damage to the inner electrode due to physical stress and / or chemical stress.

[0042] The covering parts 112 and 113 may include one or more crystal phases 10a formed of a compound containing a rare earth element, Si, and O. The upper surface of the upper covering part 112 in the first direction may form the second surface of the main body 110, and the lower surface of the lower covering part 113 in the first direction may form the first surface of the main body 110. That is to say, the second surface 2 may be the upper surface of the upper covering part 112 in the first direction, and the first surface 1 may be the lower surface of the lower covering part 113 in the first direction.

[0043] According to an embodiment, when the area ratio occupied by the crystal phase in the central part (K1) of the first surface 1 and the second surface 2 is defined as S1, and the area ratio occupied by the crystal phase in the central part (K2) of the cross-section of the covering parts 112 and 113 in the first direction and the third direction is defined as S2, S1 > S2 may be satisfied.

[0044] Since the crystal phase 10a is formed of a compound containing a rare earth element, Si, and O, the crystal phase 10a may have the characteristics of low thermal conductivity, low thermal expansibility, and low hygroscopicity.

[0045] However, when the crystal phase 10a is provided in the covering part, the crystal phase 10a may affect the electrical characteristics of the multilayer electronic component 100. Therefore, according to an embodiment, by making the area ratio S1 occupied by the crystal phase 10a in the central part K1 of the first surface 1 and the second surface 2 further larger than the area ratio S2 occupied by the crystal phase 10a in the central part K2 of the cross-section of the covering parts 112 and 113 in the first direction and the third direction, the influence on the electrical characteristics of the multilayer electronic component 100 can be reduced, and the reliability can be improved.

[0046] The rare earth element contained in the crystal phase 10a may include one or more of Y, Dy, Ho, Er, Gd, Ce, Nd, Sm, Tb, Tm, La, Gd, and Yb.

[0047] In an embodiment, the rare earth element contained in the crystal phase 10a may be yttrium (Y). When the rare earth element contained in the crystal phase 10a is yttrium (Y), the thermal conductivity, thermal expansibility, and low hygroscopicity of the crystal phase 10a can be improved. In addition, when the rare earth element contained in the crystal phase 10a is yttrium (Y), the crystal phase 10a can easily grow during the process of sintering the main body 110, rather than adding the crystal phase 10a separately, such that the crystal phase 10a can be formed without a specific process.

[0048] In an embodiment, the crystal phase 10a may be Y2Si2O7.

[0049] Y2Si2O7 may have a lower thermal conductivity and a lower coefficient of thermal expansion than BaTiO3, which is beneficial for high-temperature reliability and prevents cracking. The thermal conductivity of Y2Si2O7 may be about 1.4 W / mK, and the coefficient of thermal expansion may be about 4 ppm / K. The thermal conductivity of BaTiO3 may be about 2.8 W / mK, and the coefficient of thermal expansion may be about 10 ppm / K.

[0050] Referring to Figure 7 , in an embodiment, the ratio (Lx / Sx) of the major axis Lx to the minor axis Sx of the crystal phase 10a may be greater than or equal to 1.5 and less than or equal to 60. That is, the crystal phase 10a may have a rod shape. Therefore, the thermal conductivity can be effectively reduced and the heat absorbed from the outside can be reduced.

[0051] However, it is not necessary for all of the crystal phases 10a included in the covering parts 112 and 113 to satisfy the above conditions, and the ratio (Lx / Sx) of the major axis Lx to the minor axis Sx of one or more crystal phases 10a may satisfy greater than or equal to 1.5 and less than or equal to 60, but the exemplary embodiments are not limited thereto.

[0052] In an embodiment, the length of the minor axis Sx of the crystal phase 10a may be greater than or equal to 0.05 μm and less than or equal to 0.5 μm, and the length of the major axis Lx may be greater than or equal to 0.1 μm and less than or equal to 3.0 μm.

[0053] However, it is not necessary for all of the crystal phases 10a included in the covering parts 112 and 113 to satisfy the above conditions, and the length of the minor axis Sx of one or more crystal phases 10a may be greater than or equal to 0.05 μm and less than or equal to 0.5 μm, and the length of the major axis Lx may be greater than or equal to 0.1 μm and less than or equal to 3.0 μm, but the exemplary embodiments are not limited thereto.

[0054] In an embodiment, the area ratio S1 occupied by the crystal phase 10a in the central portion K1 of the first surface 1 and the second surface 2 may be greater than or equal to 5%. When S1 is greater than or equal to 5%, the effects of reducing the thermal conductivity and reducing the heat absorbed from the outside can be improved.

[0055] In an embodiment, the area ratio S1 occupied by the crystal phase 10a in the central portion K1 of the first surface 1 and the second surface 2 may be greater than or equal to 5% and less than or equal to 50%, and the area ratio S2 occupied by the crystal phase 10a in the central portion K2 of the cross-sections of the covering portions 112 and 113 in the first direction and the third direction may be greater than or equal to 0% and less than or equal to 0.1%.

[0056] S2 may be 0%, and thus, the influence on the electrical characteristics of the multilayer electronic component 100 can be reduced.

[0057] In an embodiment, the crystal phase 10a may have a cross-sectional area of greater than or equal to 1.0 μm 2 and, on the first surface and the second surface, the number of crystal phases 10a having a cross-sectional area of greater than or equal to 1.0 μm 2 per μm 2 may be greater than or equal to 0.25 and less than or equal to 2.0. Thus, the effects of reducing the thermal conductivity and reducing the heat absorbed from the outside can be further improved.

[0058] Furthermore, the crystal phase 10a may have a cross-sectional area of greater than or equal to 1.0 μm 2 and, on the first surface 1 and the second surface 2, the number of crystal phases 10a having a cross-sectional area of greater than or equal to 1.0 μm 2 per μm 2 may be from 0.25 to 2.0, and may be provided in the cross-sections of the covering portions 112 and 113 in the first direction and the third direction at less than or equal to 0.01 (for example, 0.001 to 0.01) per μm 2 . That is, the crystal phase 10a having a cross-sectional area of greater than or equal to 1.0 μm 2 may be provided on the first surface 1 and the second surface 2 at 0.25 to 2.0 per unit area (μm 2 ) and may be provided in the cross-sections of the covering portions 112 and 113 in the first direction and the third direction at 0.001 to 0.01 per unit area (μm 2 ).

[0059] The method for measuring the area ratio and the number per unit area (μm 2 ) of the crystal phase 10a is not limited to any specific example. For example, when the second surface is divided into three parts in the plane of the second direction and the third direction, the area ratio and the number per unit area (μm 2 ) of the crystal phase 10a in the central region (i.e., the central portion K1) of the upper covering portion 112 can be measured by analyzing the central region, and the area ratio and the number per unit area (μm 2 ) of the crystal phase 10a in the central region can be measured by analyzing this region using a scanning electron microscope (SEM).

[0060] Figure 5 is a scanning image of the central portion K1 obtained using a scanning electron microscope. Referring to Figure 1 multiple rod-like crystal phases 10a can be provided. Also, in the image, the crystal phase 10a can be clearly distinguished from the dielectric grains 10b by the difference in brightness. Therefore, the area ratio of the crystal phase 10a and the number per unit area (μm Figure 5 can be measured by the brightness difference using an image analysis program. For more accurate analysis, the area ratio of the crystal phase 10a and the number per unit area can be measured by analyzing the scanning image using a SEM-energy dispersive spectrometer (EDS). The area ratio of the crystal phase 10a can be the ratio of the area occupied by the crystal phase 10a to the area of the entire region of the scanning image, and the area ratio of the crystal phase 10a and the number per unit area (μm 2 ) can be measured in a 10 μm × 10 μm region. 2 ).

[0061] The covering portions 112 and 113 can include multiple dielectric grains 10b, and the crystal phase 10a can be provided on the dielectric grains 10b located on the first surface and the second surface. Referring to Figure 5 , the crystal phase 10a can be provided on multiple dielectric grains 10b, and a part of the crystal phase 10a can be provided at the grain boundaries between the dielectric grains 10b.

[0062] In an embodiment, the covering portions 112 and 113 can include one or more of BaTiO3, (Ba 1-x Ca x )TiO3 (0 < x < 1), Ba(Ti 1-y Ca y )O3 (0 < y < 1), (Ba 1-x Ca x )(Ti 1-y Zr y )O3 (0 < x < 1, 0 < y < 1), and Ba(Ti 1-y Zr y )O3 (0 < y < 1) as a main component.

[0063] In an embodiment, the crystal phase 10a may not include Ba and Ti. Since the crystal phase 10a does not include Ba and Ti, the crystal phase 10a can be easily distinguished from the dielectric grains 10b.

[0064] In an embodiment, the covering portions 112 and 113 can include Ba, Ti, Y, Mn, and Mg, and the crystal phase 10a may not include Ba and Ti.

[0065] The covering portion can include BaTiO3, (Ba 1-x Cax )TiO3 (0 < x < 1), Ba(Ti 1-y Ca y )O3 (0 < y < 1), (Ba 1-x Ca x )(Ti 1-y Zr y )O3 (0 < x < 1, 0 < y < 1) and Ba(Ti 1-y Zr y )O3 (0 < y < 1) as a main component, and may include Y of 3 moles or more based on 100 moles of Ti. Therefore, the crystal phase 10a can be easily formed in the sintering process.

[0066] In order to confirm that the crystal phase can be easily formed when Y based on 100 moles of Ti is 3 moles or more, the ceramic slurry for the covering part can be prepared as follows: by adding barium titanate (BaTiO3) ceramic powder as the main component, adding yttrium oxide (Y2O3), silicon dioxide (SiO2), manganese oxide (Mn3O4) and magnesium carbonate (MgCO3) as the sub-components, adding an organic solvent and a binder, coating the slurry on the carrier film and drying the slurry.

[0067] After laminating the green sheets of the ceramic for the covering part, laminate the green sheets printed with the internal electrode pattern thereon, and laminate the green sheets of the ceramic for the covering part, thereby preparing a laminate. Thereafter, the laminate is calcined at a temperature of 400 °C for 12 hours, and secondary calcination is performed at a temperature of 850 °C for 4 hours in an inert gas atmosphere. Thereafter, a sintering process is performed at a temperature of 1200 °C for 2 hours in a reducing atmosphere, thereby obtaining the main body.

[0068] The green sheets of the ceramic for the covering part of the comparative example are manufactured such that based on 100 moles of Ti, the contents of the sub-components Y, Si, Mn, and Mg are 1 mole, 2 moles, 0.15 mole, and 0.5 mole respectively, and the green sheets of the ceramic for the covering part of the inventive example are manufactured such that based on 100 moles of Ti, the contents of the sub-components Y, Si, Mn, and Mg are 3 moles, 2 moles, 0.15 mole, and 0.5 mole respectively.

[0069] Figure 5 is a scanning image of K1 obtained using a scanning electron microscope Figure 1 . Figure 8 is a view showing a scanning image of the surface of the covering part of the comparative example obtained using a scanning electron microscope. Referring to Figure 5 , in the case of the inventive example, the crystal phase 10a provided on the dielectric grains 10b is observed, but in the case of the comparative example, only the dielectric grains 10b' are observed and no crystal phase is observed.

[0070] The covering parts 112 and 113 may not include the internal electrodes 121 and 122. However, in order to improve the warpage strength, the covering parts 112 and 113 may include dummy electrodes that do not participate in capacitance formation.

[0071] The thicknesses of the covering parts 112 and 113 may not be limited to any specific example. However, in order to easily achieve miniaturization and high capacitance of the multilayer electronic component, the thickness tc of the covering parts 112 and 113 may be less than or equal to 15 μm.

[0072] The average thickness tc of the covering parts 112 and 113 may refer to the dimension in the first direction, and may be the average value of the dimensions in the first direction of the covering parts 112 and 113 measured at five points at equal distances above and below the capacitance forming part Ac.

[0073] The edge parts 114 and 115 may be provided on the side surfaces of the capacitance forming part Ac.

[0074] The edge parts 114 and 115 may include a first edge part 114 provided on one surface of the capacitance forming part Ac in the third direction and a second edge part 115 provided on the other surface of the capacitance forming part Ac in the third direction.

[0075] The edge parts 114 and 115 may refer to the regions between the two ends of the first internal electrode 121 and the second internal electrode 122 and the outer surface of the main body 110 in the width-thickness direction of the cross-section of the main body 110 as shown in Figure 3 the figure.

[0076] The edge parts 114 and 115 may substantially prevent damage to the internal electrodes caused by physical stress and / or chemical stress.

[0077] The edge parts 114 and 115 may be formed by the following method: applying a conductive paste to the regions on the green sheet of ceramic except for the regions where the edge parts are to be formed to form the internal electrodes.

[0078] The widths of the edge parts 114 and 115 may not be limited to any specific example. However, in order to easily achieve miniaturization and high capacitance of the multilayer electronic component, the average widths of the edge parts 114 and 115 may be less than or equal to 15 μm.

[0079] The average widths of the edge parts 114 and 115 may refer to the average dimension MW1 in the third direction of the region where the internal electrode is spaced apart from the fifth surface or the average dimension MW2 in the third direction of the region where the internal electrode is spaced apart from the sixth surface, and may be the average value of the dimensions in the third direction of the edge parts 114 and 115 measured at five points at equal distances on the side surfaces of the capacitance forming part Ac.

[0080] Thus, in an embodiment, the average dimensions MW1 and MW2 in the third direction of the regions where the inner electrodes 121 and 122 are spaced apart from the fifth surface and the sixth surface may be less than or equal to 15 μm, respectively.

[0081] The outer electrodes 131 and 132 may be disposed on the third surface 3 and the fourth surface 4 of the main body 110.

[0082] The outer electrodes 131 and 132 may be respectively disposed on the third surface 3 and the fourth surface 4 of the main body 110, and may include a first outer electrode 131 and a second outer electrode 132 respectively connected to the first inner electrode 121 and the second inner electrode 122.

[0083] In an embodiment, the multilayer electronic component 100 may have two outer electrodes 131 and 132, but the number or the shape of the outer electrodes may vary according to the shape of the inner electrodes or other purposes.

[0084] The outer electrodes 131 and 132 may be formed of any material having conductivity, such as a metal, and the specific material may be determined by considering electrical characteristics and structural stability, and may further have a multilayer structure.

[0085] For example, the outer electrodes 131 and 132 may include electrode layers 131a and 132a disposed on the main body 110 and plating layers 131b and 132b formed on the electrode layers 131a and 132a.

[0086] For more specific examples of the electrode layers 131a and 132a, the electrode layers 131a and 132a may be fired electrodes including a conductive metal and glass, or resin electrodes including a conductive metal and a resin.

[0087] In addition, in the electrode layers 131a and 132a, the fired electrodes and the resin electrodes may be formed on the main body in sequence. In addition, the electrode layers 131a and 132a may be formed by transferring a sheet including a conductive metal to the main body, or may be formed by transferring a sheet including a conductive metal to the fired electrodes.

[0088] Materials having excellent conductivity may be used as the conductive metal included in the electrode layers 131a and 132a, and are not limited to any specific examples. For example, the conductive metal may be one or more of nickel (Ni), copper (Cu), and their alloys.

[0089] The plating layers 131b and 132b improve the mounting characteristics. The types of the plating layers 131b and 132b are not limited to any specific examples, and may be plating layers including one or more of Ni, Sn, Pd, and their alloys, and may be formed into multiple layers.

[0090] For more specific examples of the coatings 131b and 132b, the coatings 131b and 132b may be Ni coatings or Sn coatings, and may be a Ni coating and an Sn coating formed in sequence on the electrode layers 131a and 132a, or may be an Sn coating, a Ni coating, and an Sn coating formed in sequence on the electrode layers 131a and 132a. In addition, the coatings 131b and 132b may include multiple Ni coatings and / or multiple Sn coatings.

[0091] The size of the multilayer electronic component 100 may not be limited to any specific example. For example, the length L of the multilayer electronic component 100 may be from 0.4 mm to 5.7 mm, the thickness T of the multilayer electronic component 100 may be from 0.1 mm to 3.2 mm, and the width W of the multilayer electronic component 100 may be from 0.2 mm to 5.0 mm.

[0092] Here, the length L of the multilayer electronic component 100 may refer to the maximum size of the multilayer electronic component 100 in the second direction, the thickness T of the multilayer electronic component 100 may refer to the maximum size of the multilayer electronic component 100 in the first direction, and the width W of the multilayer electronic component 100 may refer to the maximum size of the multilayer electronic component 100 in the third direction.

[0093] According to the foregoing embodiments, by providing a crystal phase formed of a compound containing rare earth elements, Si, and O on the surface of the covering portion, the reliability of the multilayer electronic component can be improved.

[0094] In addition, the high-temperature reliability of the multilayer electronic component can be improved.

[0095] The scope of the present disclosure is not limited to the above specific forms of embodiments, and the scope of the present disclosure may include modifications, equivalents, and substitutions included in the disclosed concept and technical scope of this specification.

[0096] In the embodiments, the term "embodiment" may not refer to the same embodiment, and may be provided to describe and emphasize different unique features of each embodiment. The possibility of combining features in one embodiment with features in other embodiments is not excluded. For example, unless otherwise stated, even if the features described in one embodiment are not described in another embodiment, the description may be understood as being related to another embodiment.

[0097] Unless having an obviously different meaning in the context, expressions used in the singular cover plural expressions.

[0098] 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 body including a capacitance forming portion and a covering portion, the capacitance forming portion including a dielectric layer and inner electrodes alternately arranged with the dielectric layer in a first direction, the covering portion being respectively arranged on an upper portion and a lower portion of the capacitance forming portion in the first direction, and the body including 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 a third direction; an outer electrode, disposed on the body, wherein the covering portion includes one or more crystalline phases, the crystalline phases including a compound of a rare earth element, Si and O, and Wherein, when the area ratio occupied by the crystal phase in the central part of at least one of the first surface and the second surface is defined as S1, and the area ratio occupied by the crystal phase in the central part of the cross-section of at least one of the covering parts in the first direction and the third direction is defined as S2, S1>S2 is satisfied, and the at least one of the first surface and the second surface is the outer surface of the covering part.

2. The multilayer electronic component according to claim 1, wherein The rare earth element includes yttrium.

3. The multilayer electronic component according to claim 1, wherein: The crystalline phase includes Y2Si2O7.

4. The multilayer electronic component according to claim 1, wherein: The ratio of the major axis to the minor axis of the crystal phase is greater than or equal to 1.5 and less than or equal to 60.

5. The multilayer electronic component according to claim 1, wherein The length of the short axis of the crystal phase is greater than or equal to 0.05 μm and less than or equal to 0.5 μm, and the length of the long axis of the crystal phase is greater than or equal to 0.1 μm and less than or equal to 3.0 μm.

6. The multilayer electronic component according to claim 1, wherein S1 is greater than or equal to 5%.

7. The multilayer electronic component according to claim 1, in, S1 is greater than or equal to 5% and less than or equal to 50%, and Among them, S2 is greater than or equal to 0% and less than or equal to 0.1%.

8. The multilayer electronic component according to claim 1, in, The cross-sectional area of ​​the crystal phase is greater than or equal to 1.0 μm 2 ,and Wherein, the crystalline phase is greater than or equal to 0.25 / μm 2 And less than or equal to 2.0 / μm 2 The device is disposed on at least one of the first surface and the second surface.

9. The multilayer electronic component according to claim 1, in, The cross-sectional area of ​​the crystal phase is greater than or equal to 1.0 μm 2 , Wherein, the crystalline phase is greater than or equal to 0.25 / μm 2 And less than or equal to 2.0 / μm 2 is disposed on both the first surface and the second surface, and Wherein, the crystalline phase is less than or equal to 0.01 / μm 2 The at least one covering portion is provided in the cross section in the first direction and the third direction.

10. The multilayer electronic component according to claim 1, in, At least one of the covering portions includes a plurality of dielectric grains, and The crystalline phase is disposed on the dielectric grains located on at least one of the first surface and the second surface.

11. The multilayer electronic component according to claim 1, wherein At least one of the covering parts includes one or more of the following components as a main component: BaTiO3, (Ba 1-x Ca x )TiO3、Ba(Ti 1-y Ca y )O3、 (Ba 1- x Ca x )(Ti 1-y Zr y )O3 and Ba(Ti 1-y Zr y )O3, where 0 <x<1, 0<y<1。 12. The multilayer electronic component according to claim 1, wherein The crystalline phase does not include Ba and Ti.

13. The multilayer electronic component according to claim 1, in, In addition to the crystalline phase, at least one of the covering portions further includes Ba, Ti, Mn and Mg, and Wherein, the crystalline phase does not include Ba and Ti.

14. The multilayer electronic component according to claim 1, wherein At least one of the covering portions in the covering portion includes one or more of the following components as main components: BaTiO3, (Ba 1-x Ca x )TiO3, Ba(Ti 1-y Ca y )O3, (Ba 1- x Ca x )(Ti 1-y Zr y )O3, and Ba(Ti 1-y Zr y )O3, where 0 < x < 1, 0 < y < 1, and The at least one of the covering portions includes 3 mol or more of Y based on 100 mol of Ti.

15. The multilayer electronic component according to claim 1, wherein The crystalline phase has a rod shape.

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