Multilayer electronic component

Abstract

To provide a multilayer electronic component whose reliability is improved by adding a relatively small content of rare earth elements.SOLUTION: A multilayer electronic component includes a body 110 including a capacitance formation portion Ac including dielectric layers 111a, 111b and internal electrodes, and cover portions 112, 113 disposed on both ends of the capacitance formation portion in a first direction; and external electrodes disposed on the body. The capacitance formation portion includes an internal portion 141 disposed in a central portion in the first direction of the capacitance formation portion and an external portion 142-1, 142-2 disposed between the internal portion and the cover portions. When the average number of moles of rare earth elements based on 100 moles of titanium (Ti) included in the internal portion is defined as RE1, the average number of moles of rare earth elements based on 100 moles of titanium (Ti) included in the external portion is defined as RE2, and the average number of moles of rare earth elements based on 100 moles of titanium (Ti) included in the cover portion is defined as RE3, RE1<RE2 and RE3<RE2 are satisfied.SELECTED DRAWING: Figure 5

Description

Technical Field

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

Background Art

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

[0003] Such a multilayer ceramic capacitor can be used as a component of various electronic devices due to its advantages of being small in size while ensuring high capacitance and being easy to mount. As various electronic devices such as computers and mobile devices are miniaturized and have increased output, the demand for miniaturization and high capacitance of multilayer ceramic capacitors is increasing.

[0004] On the one hand, multilayer electronic components must have excellent reliability so that they can operate smoothly even in harsh environments such as high temperature, high pressure, and high voltage. To solve this problem, the reliability is improved by adding rare earth elements. More specifically, the mechanism of "deterioration", which is directly related to reliability, is affected by the movement of oxygen vacancies. To suppress such deterioration, it is possible to reduce the concentration of oxygen vacancies itself to prevent the degradation of insulation resistance under high-temperature environments. To minimize the degradation of insulation resistance, a microstructure such as crystal grains with a core-shell structure containing rare earth elements at a certain ratio or more is realized to improve the reliability of multilayer ceramic capacitors. However, if rare earth elements are added excessively, there may be problems such as a decrease in dielectric constant or failure to meet the target temperature change (Temperature Coefficient of Capacitance, TCC) characteristics of capacitance, and there may be drawbacks such as being uneconomical.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] One of the several problems to be solved by the present invention is to provide a multilayer electronic component with excellent reliability even when a small amount of rare earth elements is added.

[0007] One of the several problems to be solved by the present invention is to provide a multilayer electronic component with excellent reliability even when rare earth elements are added differently according to the region of the multilayer electronic component.

[0008] However, some problems to be solved by the present invention are not limited to the above-described content and can be more easily understood in the process of explaining specific embodiments of the present invention.

Means for Solving the Problems

[0009] A multilayer electronic component according to an embodiment of the present invention includes a capacitance forming portion including a dielectric layer and internal electrodes alternately arranged with the dielectric layer in a first direction, and a main body including cover portions arranged on both end faces of the capacitance forming portion in the first direction, and external electrodes arranged on the main body. The capacitance forming portion includes an inner portion located at a central portion of the capacitance forming portion in the first direction, and an outer portion located between the inner portion and the cover portion. When the average number of moles of a rare earth element per 100 moles of titanium (Ti) contained in the inner portion is RE1, the average number of moles of the rare earth element per 100 moles of titanium (Ti) contained in the outer portion is RE2, and the average number of moles of the rare earth element per 100 moles of titanium (Ti) contained in the cover portion is RE3, RE1 < RE2 and RE3 < RE2 can be satisfied.

Advantages of the Invention

[0010] One of several effects of the present invention is to improve the reliability of the multilayer electronic component by adding a small amount of rare earth elements.

[0011] One of several effects of the present invention is to improve the reliability of the multilayer electronic component by adding different amounts of rare earth elements in different regions of the multilayer electronic component.

[0012] However, the diverse and beneficial advantages and effects of the present invention are not limited to the above-described content and can be more easily understood in the process of explaining specific embodiments of the present invention.

Brief Description of the Drawings

[0013]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Embodiments for Carrying Out the Invention

[0014] Hereinafter, embodiments of the present invention will be described with reference to specific embodiments and the accompanying drawings. However, the embodiments of the present invention can be deformed into various other forms, and the scope of the present invention is not limited to the embodiments described below. Also, the embodiments of the present invention are provided to more fully explain the present invention to ordinary technicians. Therefore, the shape and size of elements in the drawings can be exaggerated for clearer explanation, and elements denoted by the same reference numerals in the drawings are the same elements.

[0015] And, in order to clearly explain the present invention in the drawings, parts not related to the explanation are omitted, and the sizes and thicknesses of each configuration shown in the drawings are arbitrarily shown for convenience of explanation, so the present invention is not necessarily limited to what is shown in the drawings. Note that components having the same function within the scope of the same concept are described using the same reference numerals. Further, throughout the specification, when a part says that a certain component "includes", this means that other components can be further included, rather than excluding other components, unless otherwise stated to the contrary.

[0016] In the drawings, the first direction can be defined as the stacking direction or the thickness T direction, the second direction as the length L direction, and the third direction as the width W direction.

[0017] Multilayer electronic component FIG. 1 schematically shows a perspective view of a multilayer electronic component according to an embodiment of the present invention, FIG. 2 schematically shows an exploded perspective view showing the stacked structure of internal electrodes, FIG. 3 schematically shows a cross-sectional view taken along line I-I' of FIG. 1, FIG. 4 schematically shows a cross-sectional view taken along line II-II' of FIG. 1, FIG. 5 schematically shows FIG. 3 divided by region, FIG. 6 is a graph schematically showing the content of rare earth elements along line LP-LP' of FIG. 5 in one embodiment of the present invention, and FIG. 7 is a graph schematically showing the content of rare earth elements along line LP-LP' of FIG. 5 in another embodiment of the present invention.

[0018] Hereinafter, with reference to FIGS. 1 to 7, a multilayer electronic component according to an embodiment of the present invention will be described in detail. However, although a multilayer ceramic capacitor will be described as an example of the multilayer electronic component, the present invention can also be applied to various electronic products using a dielectric composition, such as an inductor, a piezoelectric element, a varistor, or a thermistor.

[0019] A stacked electronic component 100 according to an embodiment of the present invention includes a capacitance forming portion Ac including dielectric layers 111a, 111b and internal electrodes 121, 122 alternately arranged in the first direction with the dielectric layers 111a, 111b, and a main body 110 including cover portions 112, 113 arranged on both end - surfaces in the first direction of the capacitance forming portion Ac, and external electrodes 131, 132 arranged on the main body 110. The capacitance forming portion Ac includes an inner portion 141 located at the central portion of the capacitance forming portion in the first direction, and an outer portion 142 located between the inner portion 141 and the cover portions 112, 113. When the average number of moles of rare - earth elements per 100 moles of titanium (Ti) included in the inner portion 141 is RE1, the average number of moles of rare - earth elements per 100 moles of titanium (Ti) included in the outer portion 142 is RE2, and the average number of moles of rare - earth elements per 100 moles of titanium (Ti) included in the cover portions 112, 113 is RE3, RE1 < RE2 and RE3 < RE2 can be satisfied.

[0020] The main body 110 may have the first and second dielectric layers 111a, 111b and the internal electrodes 121, 122 alternately laminated.

[0021] More specifically, the main body 110 can include a capacitance forming portion Ac disposed inside the main body 110 and including a first internal electrode 121 and a second internal electrode 122 alternately arranged so as to face each other with the first and second dielectric layers 111a, 111b interposed therebetween to form a capacitance.

[0022] On the other hand, the capacitance forming portion Ac can include an inner portion 141 and an outer portion 142 which will be described later. Here, the dielectric layer included in the inner portion 141 can be called the first dielectric layer 111a, and the dielectric layer included in the outer portion 142 can be called the second dielectric layer 111b. More specifically, the dielectric layer included in the first outer portion 142 - 1 can be called the second - 1 dielectric layer 111b - 1, and the dielectric layer included in the second outer portion 142 - 2 can be called the second - 2 dielectric layer 111b - 2.

[0023] In the present invention, when the multilayer electronic component 100 includes the cover portions 112 and 113, the dielectric layers included in the cover portions 112 and 113 can be defined as the third dielectric layer 111c (not shown in the drawings). When the multilayer electronic component 100 includes the side margin portions 114 and 115, the dielectric layers included in the side margin portions 114 and 115 can be defined as the fourth dielectric layer 111d (not shown in the drawings).

[0024] In the present invention, although the third dielectric layer 111c and the fourth dielectric layer 111d are not separately shown in the drawings, for convenience of explanation, they will be described together with the reference numerals in the drawings.

[0025] There is no particular limitation on the specific shape of the main body 110. As shown in the drawings, the main body 110 can be formed in a hexahedron shape or a shape similar thereto. Due to the shrinkage of the ceramic particles included in the main body 110 during the firing process, the main body 110 does not have a perfect hexahedron shape with straight lines, but can have a substantially hexahedron shape.

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

[0027] The plurality of first and second dielectric layers 111a, 111b forming the main body 110 are in a fired state, and the boundaries between adjacent dielectric layers 111 can be integrated so as to be difficult to confirm without using a scanning electron microscope (SEM).

[0028] The raw materials for forming the first and second dielectric layers 111a, 111b are not limited as long as sufficient capacitance can be obtained. Generally, perovskite (ABO 3 )-based materials can be used. For example, barium titanate-based materials, lead composite perovskite-based materials, or strontium titanate-based materials can be used. The barium titanate-based materials are BaTiO 3It can contain ceramic particles. Examples of ceramic particles include BaTiO 3 , BaTiO 3 in which Ca (calcium), Zr (zirconium), etc. are partially solid-solved (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) or Ba(Ti 1-y Zr y )O 3 (0 < y < 1), etc.

[0029] Also, the raw materials for forming the first and second dielectric layers 111a and 111b can be particles such as barium titanate (BaTiO 3 ), and various additives, organic solvents, binders, dispersants, etc. can be added according to the object of the present invention. For example, the first and second dielectric layers 111a and 111b can further contain rare earth elements, but are not particularly limited thereto. The first dielectric layer 111a may not contain rare earth elements, and only the second dielectric layer 111b can contain rare earth elements.

[0030] Also, since the first and second dielectric layers 111a and 111b can be formed using a dielectric material such as barium titanate (BaTiO 3 ), they can contain a dielectric fine structure after firing. The dielectric fine structure can include a plurality of crystal grains, grain boundaries disposed between the adjacent crystal grains, and triple points disposed at points where three or more of the grain boundaries meet, and each can include a plurality.

[0031] The thickness td of the first and second dielectric layers 111a and 111b does not need to be particularly limited.

[0032] In order to ensure the reliability of the multilayer electronic component 100 under high voltage environments, the thicknesses of the first and second dielectric layers 111a and 111b may be 10.0 μm or less. Further, in order to achieve miniaturization and high capacitance of the multilayer electronic component 100, the thicknesses of the first and second dielectric layers 111a and 111b may be 3.0 μm or less. In order to more easily achieve ultra-miniaturization and high capacitance, the thicknesses of the first and second dielectric layers 111a and 111b may be 1.0 μm or less, preferably 0.6 μm or less, and more preferably 0.4 μm or less.

[0033] Here, the thickness td of the first and second dielectric layers 111a and 111b can mean the thickness td of the first and second dielectric layers 111a and 111b disposed between the first and second internal electrodes 121 and 122.

[0034] On the other hand, the thickness td of the first and second dielectric layers 111a and 111b can mean the size of the dielectric layer 111 in the first direction. Further, the thickness td of the first and second dielectric layers 111a and 111b can mean the average thickness td of the dielectric layer 111, and can mean the average size of the first and second dielectric layers 111a and 111b in the first direction.

[0035] The average size of the first and second dielectric layers 111a and 111b in the first direction can be measured by scanning an image of the cross-sections of the main body 110 in the first and second directions with a scanning electron microscope (SEM) at a magnification of 10,000 times. More specifically, the average size of one of the first and second dielectric layers 111a and 111b in the first direction can mean the average value calculated by measuring the size in the first direction at 10 points that are equally spaced in the second direction for one of the first and second dielectric layers 111a and 111b in the scanned image. The 10 equally spaced points can be specified in the capacitance forming portion Ac. Further, when such measurement of the average value is extended to 10 of the first and second dielectric layers 111a and 111b to measure the average value, the average size of the first and second dielectric layers 111a and 111b in the first direction can be further generalized.

[0036] The internal electrodes 121 and 122 may be alternately laminated with the first and second dielectric layers 111a and 111b.

[0037] The internal electrodes 121 and 122 can include a first internal electrode 121 and a second internal electrode 122. The first and second internal electrodes 121 and 122 are alternately arranged so as to face each other with the first and second dielectric layers 111a and 111b that constitute the main body 110 interposed therebetween, and can be exposed on the third and fourth surfaces 3 and 4 of the main body 110, respectively.

[0038] More specifically, the first internal electrode 121 is spaced apart from the fourth surface 4 and can be exposed through the third surface 3, and the second internal electrode 122 is spaced apart from the third surface 3 and can be exposed through the fourth surface 4. A first external electrode 131 is disposed on the third surface 3 of the main body 110 and can be connected to the first internal electrode 121, and a second external electrode 132 is disposed on the fourth surface 4 of the main body 110 and can be connected to the second internal electrode 122.

[0039] That is, the first internal electrode 121 is not connected to the second external electrode 132 but can be connected to the first external electrode 131, and the second internal electrode 122 is not connected to the first external electrode 131 but can be connected to the second external electrode 132. At this time, the first and second internal electrodes 121 and 122 can be electrically separated from each other by the first and second dielectric layers 111a and 111b disposed in the middle.

[0040] On the other hand, the main body 110 can be formed by alternately laminating a ceramic green sheet printed with the first internal electrode 121 and a ceramic green sheet printed with the second internal electrode 122 and then firing them.

[0041] The materials for forming the internal electrodes 121 and 122 are not particularly limited, and materials having excellent electrical conductivity can be used. For example, the internal electrodes 121 and 122 can include one or more of nickel (Ni), copper (Cu), palladium (Pd), silver (Ag), gold (Au), platinum (Pt), tin (Sn), tungsten (W), titanium (Ti), and alloys thereof.

[0042] Also, the internal electrodes 121 and 122 can be formed by printing a conductive paste for internal electrodes containing one or more of nickel (Ni), copper (Cu), palladium (Pd), silver (Ag), gold (Au), platinum (Pt), tin (Sn), tungsten (W), titanium (Ti), and alloys thereof on a ceramic green sheet. As the printing method of the conductive paste for internal electrodes, a screen printing method, a gravure printing method, or the like can be used, but the present invention is not limited thereto.

[0043] On the other hand, the thickness te of the internal electrodes 121 and 122 does not need to be particularly limited.

[0044] In order to ensure the reliability of the multilayer electronic component 100 in a high voltage environment, the thickness te of the internal electrodes 121 and 122 may be 3.0 μm or less. Also, in order to achieve miniaturization and high capacitance of the multilayer electronic component 100, the thickness of the internal electrodes 121 and 122 may be 1.0 μm or less. In order to more easily achieve ultra-miniaturization and high capacitance, the thickness of the internal electrodes 121 and 122 may be 0.6 μm or less, and more preferably 0.4 μm or less.

[0045] Here, the thickness te of the internal electrodes 121 and 122 can mean the size of the internal electrodes 121 and 122 in the first direction. Also, the thickness te of the internal electrodes 121 and 122 can mean the average thickness te of the internal electrodes 121 and 122, and can mean the average size of the internal electrodes 121 and 122 in the first direction.

[0046] The average size of the internal electrodes 121 and 122 in the first direction can be measured by scanning an image of the cross-sections 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 size of one internal electrode in the first direction can be the average value calculated by measuring the size of one internal electrode in the first direction at 10 equally spaced points in the second direction in the scanned image. The 10 equally spaced points can be specified in the capacitance forming portion Ac. Also, when such measurement of the average value is extended to 10 internal electrodes to measure the average value, the average size of the internal electrodes in the first direction can be further generalized.

[0047] On the other hand, in one embodiment of the present invention, the internal electrodes 121 and 122 adjacent in the first direction can include regions protruding in the first direction toward each other. For example, they can include regions protruding in a convex shape. When the internal electrodes 121 and 122 include regions protruding convexly toward each other, the size of the first and second dielectric layers 111a and 111b arranged between the internal electrodes 121 and 122 in the first direction can be reduced. According to this, there is a possibility of dielectric breakdown due to a reduction in the thickness of the dielectric layer to which an electric field is applied. At this time, when the region where the thickness of the first and second dielectric layers 111a and 111b is reduced contains a rare earth element, the electric field concentration phenomenon can be alleviated to prevent the occurrence of dielectric breakdown.

[0048] On the other hand, in one embodiment of the present invention, the average thickness td of at least one of the plurality of dielectric layers 111 and the average thickness te of at least one of the plurality of internal electrodes 121 and 122 can satisfy 2×te < td.

[0049] In other words, the average thickness td of one of the dielectric layers 111 may be even greater than twice the average thickness te of one of the internal electrodes 121 and 122. Preferably, the average thickness td of the plurality of dielectric layers 111 may be even greater than twice the average thickness te of the plurality of internal electrodes 121 and 122.

[0050] Generally, for electronic components used in high-voltage electrical equipment, the main issue is the reliability problem due to the decrease in breakdown voltage (BDV) under high-voltage environments.

[0051] Therefore, in order to prevent the decrease in breakdown voltage under high-voltage environments, by making the average thickness td of the dielectric layer 111 greater than twice the average thickness te of the internal electrodes 121 and 122, the thickness of the dielectric layer, which is the distance between the internal electrodes, can be increased, and the breakdown voltage characteristics can be improved.

[0052] When the average thickness td of the dielectric layer 111 is less than or equal to twice the average thickness te of the internal electrodes 121 and 122, the average thickness of the dielectric layer, which is the distance between the internal electrodes, becomes thin, and the breakdown voltage may decrease, and there may be a possibility of a short circuit between the internal electrodes.

[0053] On the other hand, the main body 110 can include cover portions 112 and 113 disposed on both end-surfaces in the first direction of the capacitance forming portion Ac.

[0054] Specifically, it can include a first cover portion 112 disposed on one surface in the first direction of the capacitance forming portion Ac and a second cover portion 113 disposed on the other surface in the first direction of the capacitance forming portion Ac. More specifically, it can include an upper cover portion 112 disposed on the upper part in the first direction of the capacitance forming portion Ac and a lower cover portion 113 disposed on the lower part in the first direction of the capacitance forming portion Ac.

[0055] The upper cover portion 112 and the lower cover portion 113 can be formed by laminating a single third dielectric layer 111c or two or more third dielectric layers 111c in the first direction on the upper and lower surfaces of the capacitance forming portion Ac, and basically, they can play a role in preventing damage to the internal electrodes 121 and 122 due to physical or chemical stress.

[0056] The upper cover portion 112 and the lower cover portion 113 do not include the internal electrodes 121 and 122 and can contain the same materials as the first and second dielectric layers 111a and 111b. That is, the upper cover portion 112 and the lower cover portion 113 can contain a ceramic material, for example, barium titanate (BaTiO 3 )-based ceramic material and can further contain rare earth elements.

[0057] Also, since the cover portions 112 and 113 can be formed using a dielectric substance such as barium titanate (BaTiO 3 ), they can contain a dielectric microstructure after firing. The dielectric microstructure can include a plurality of crystal grains, grain boundaries disposed between the adjacent crystal grains, and triple points disposed at locations where three or more of the grain boundaries meet, and each can include a plurality of them.

[0058] On the other hand, the thickness tc of the cover portions 112 and 113 does not need to be particularly limited.

[0059] However, in order to more easily achieve miniaturization and high capacitance of the multilayer electronic component, the thickness tc of the cover portions 112 and 113 may be 100 μm or less, preferably 30 μm or less, and in the case of a super-small product, more preferably 20 μm or less.

[0060] Here, the thickness tc of the cover portions 112 and 113 can mean the size of the cover portions 112 and 113 in the first direction. Also, the thickness tc of the cover portions 112 and 113 can mean the average thickness tc of the cover portions 112 and 113 and can mean the average size of the cover portions 112 and 113 in the first direction.

[0061] The average size of the cover parts 112 and 113 in the first direction can be measured by scanning an image of the cross-sections of the main body 110 in the first and second directions with a scanning electron microscope (SEM) at a magnification of 10,000 times. More specifically, in an image of a scanned cover part, it can mean the average value calculated by measuring the size in the first direction at 10 equally spaced points in the second direction.

[0062] In addition, the average size of the cover part in the first direction measured by the above-described method can have substantially the same size as the average size of the cover part in the cross-sections of the main body 110 in the first and third directions.

[0063] On the other hand, the multilayer electronic component 100 can include side margin parts 114 and 115 disposed on both end-surfaces of the main body 110 in the third direction.

[0064] More specifically, the side margin parts 114 and 115 can include a first side margin part 114 disposed on the fifth surface 5 of the main body 110 and a second side margin part 115 disposed on the sixth surface 6 of the main body 110.

[0065] As shown in the figure, the side margin parts 114 and 115 can mean the regions between the boundary surfaces of the main body 110 and the end-surfaces in the third direction of the first and second internal electrodes 121 and 122 with reference to the cross-sections of the main body 110 in the first and third directions.

[0066] Alternatively, the side margin portions 114 and 115 are formed by applying a conductive paste to the ceramic green sheet applied to the capacitance forming portion Ac, except for the locations where the side margin portions 114 and 115 are formed, to form the internal electrodes 121 and 122. In order to suppress the step formed by the internal electrodes 121 and 122, after cutting so that the internal electrodes 121 and 122 after lamination are exposed on the fifth and sixth surfaces 5 and 6 of the main body 110, a single fourth dielectric layer 111d or two or more fourth dielectric layers 111d may be laminated in the third direction on both end-surfaces in the third direction of the capacitance forming portion Ac.

[0067] The side margin portions 114 and 115 can basically play a role in preventing damage to the internal electrodes 121 and 122 due to physical or chemical stress.

[0068] The first side margin portion 114 and the second side margin portion 115 do not include the internal electrodes 121 and 122 and can include the same materials as the first and second dielectric layers 111a and 111b. That is, the first side margin portion 114 and the second side margin portion 115 can include a ceramic material. For example, they can include a barium titanate (BaTiO 3 )-based ceramic material and can further include rare earth elements.

[0069] In addition, since the side margin portions 114 and 115 can be formed using a dielectric material such as barium titanate (BaTiO 3 ), they can include a dielectric microstructure after firing. The dielectric microstructure can include a plurality of crystal grains, grain boundaries disposed between the adjacent crystal grains, and triple points disposed at locations where three or more of the grain boundaries meet, and each can include a plurality of them.

[0070] On the other hand, the widths wm of the first and second side margin portions 114 and 115 do not need to be particularly limited.

[0071] However, in order to more easily achieve miniaturization and high capacitance of the stacked electronic component 100, the width wm of the side margin portions 114 and 115 may be 100 μm or less, preferably 30 μm or less, and in the case of a super-small product, more preferably 20 μm or less.

[0072] Here, the width wm of the side margin portions 114 and 115 can mean the size of the side margin portions 114 and 115 in the third direction. Also, the width wm of the side margin portions 114 and 115 can mean the average width wm of the side margin portions 114 and 115, and can mean the average size of the side margin portions 114 and 115 in the third direction.

[0073] The average size of the side margin portions 114 and 115 in the third direction can be measured by scanning an image of the cross-section of the main body 110 in the first and third directions with a scanning electron microscope (SEM) at a magnification of 10,000 times. More specifically, in an image obtained by scanning one side margin portion, it can mean the average value calculated by measuring the size in the third direction at 10 points equally spaced in the first direction.

[0074] In one embodiment of the present invention, a structure in which the stacked electronic component 100 has two external electrodes 131 and 132 is described, but the number, shape, etc. of the external electrodes 131 and 132 can be changed according to the form of the internal electrodes 121 and 122 and other purposes.

[0075] The external electrodes 131 and 132 are disposed on the main body 110 and can be connected to the internal electrodes 121 and 122.

[0076] More specifically, the external electrodes 131 and 132 can be respectively arranged on the third and fourth surfaces 3 and 4 of the main body 110, and can include the first and second external electrodes 131 and 132 respectively connected to the first and second internal electrodes 121 and 122. That is, the first external electrode 131 can be arranged on the third surface 3 of the main body and connected to the first internal electrode 121, and the second external electrode 132 can be arranged on the fourth surface 4 of the main body and connected to the second internal electrode 122.

[0077] Also, the external electrodes 131 and 132 can be extended and arranged on a part of the first and second surfaces 1 and 2 of the main body 110, or can be extended and arranged on a part of the fifth and sixth surfaces 5 and 6 of the main body 110. That is, the first external electrode 131 can be arranged on a part of the first, second, fifth, and sixth surfaces 1, 2, 5, and 6 of the main body 110, and on the third surface 3 of the main body 110, and the second external electrode 132 can be arranged on a part of the first, second, fifth, and sixth surfaces 1, 2, 5, and 6 of the main body 110, and on the third surface 3 of the main body 110.

[0078] On the other hand, as long as the external electrodes 131 and 132 have electrical conductivity such as metal, they can be formed using any substance, and specific substances can be determined in consideration of electrical characteristics, structural stability, etc., and they may further have a multilayer structure.

[0079] For example, the external electrodes 131 and 132 can include an electrode layer arranged on the main body 110 and a plating layer arranged on the electrode layer.

[0080] To give a more specific example of the electrode layer, the electrode layer can include the first electrode layers 131a and 132a which are fired electrodes containing the first conductive metal and glass, or can include the second electrode layers 131b and 132b which are resin-based electrodes containing the second conductive metal and resin.

[0081] Here, the conductive metals included in the first electrode layers 131a and 132a can be referred to as the first conductive metals, and the conductive metals included in the second electrode layers 131b and 132b can be referred to as the second conductive metals. At this time, the first conductive metal and the second conductive metal may be the same as or different from each other. When including a plurality of conductive metals, only some of them may include the same conductive metal, but it is not particularly limited thereto.

[0082] Also, the electrode layers 131a, 132a, 131b, and 132b may be in a form in which a fired electrode and a resin-based electrode are sequentially formed on the main body 110.

[0083] Also, the electrode layers 131a, 132a, 131b, and 132b may be formed by a method of transferring a sheet containing a conductive metal onto the main body, or may be formed by a method of transferring a sheet containing a conductive metal onto a fired electrode.

[0084] Materials excellent in electrical conductivity can be used as the conductive metals included in the electrode layers 131a, 132a, 131b, and 132b. For example, as the conductive metal, one or more selected from the group consisting of nickel (Ni), copper (Cu), palladium (Pd), silver (Ag), gold (Au), platinum (Pt), tin (Sn), tungsten (W), titanium (Ti), and alloys thereof can be included, but it is not particularly limited thereto.

[0085] In one embodiment of the present invention, the electrode layers 131a, 132a, 131b, and 132b can have a two-layer structure including the first electrode layers 131a and 132a and the second electrode layers 131b and 132b. Thereby, the external electrodes 131 and 132 can include the first electrode layers 131a and 132a including the first conductive metal and glass, and the second electrode layers 131b and 132b disposed on the first electrode layers 131a and 132a and including the second conductive metal and resin.

[0086] By including glass, the first electrode layers 131a and 132a play a role in improving the bonding property with the main body 110. By including resin, the second electrode layers 131b and 132b can play a role in improving the bending strength.

[0087] The first conductive metal contained in the first electrode layers 131a and 132a is not particularly limited as long as it can be electrically connected to the internal electrodes 121 and 122 for forming capacitance. For example, it can include one or more selected from the group consisting of nickel (Ni), copper (Cu), palladium (Pd), silver (Ag), gold (Au), platinum (Pt), tin (Sn), tungsten (W), titanium (Ti), and alloys thereof.

[0088] The first electrode layers 131a and 132a can be formed by applying a conductive paste provided by adding glass frit to the first conductive metal particles and then firing.

[0089] The second conductive metal contained in the second electrode layers 131b and 132b can play a role in being electrically connected to the first electrode layers 131a and 132a.

[0090] The conductive metal contained in the second electrode layers 131b and 132b is not particularly limited as long as it can be electrically connected to the electrode layers 131a and 132a, and can include one or more selected from the group consisting of nickel (Ni), copper (Cu), palladium (Pd), silver (Ag), gold (Au), platinum (Pt), tin (Sn), tungsten (W), titanium (Ti), and alloys thereof.

[0091] The second conductive metal contained in the second electrode layers 131b and 132b can include one or more of spherical particles and flake-shaped particles. That is, the second conductive metal can consist only of flake-shaped particles, or only of spherical particles, or can be in a form in which flake-shaped particles and spherical particles are mixed. Here, the spherical particles can include forms that are not completely spherical, for example, forms in which the length ratio of the major axis to the minor axis (major axis / minor axis) is 1.45 or less. The flake-shaped particles mean particles having a flat and elongated form, and are not particularly limited, but for example, the length ratio of the major axis to the minor axis (major axis / minor axis) can be 1.95 or more. The lengths of the major axis and the minor axis of the above spherical particles and flake-shaped particles can be measured from an image obtained by scanning a cross-section in the first and second directions cut at the central part in the third direction of the multilayer electronic component with a scanning electron microscope (SEM).

[0092] The resin contained in the second electrode layers 131b and 132b can play a role in ensuring bonding properties and absorbing shock. The resin contained in the second electrode layers 131b and 132b is not particularly limited as long as it has bonding properties and shock absorbency and can be mixed with the second conductive metal particles to produce a paste. For example, it can include an epoxy resin.

[0093] Also, the second electrode layers 131b and 132b can include a plurality of second conductive metal particles, an intermetallic compound, and a resin. By including the intermetallic compound, the electrical connectivity with the first electrode layers 131a and 132a can be further improved. The above intermetallic compound can play a role in connecting a plurality of metal particles to improve electrical connectivity and can play a role in surrounding and connecting the plurality of metal particles to each other.

[0094] At this time, the intermetallic compound can contain a metal having a melting point lower than the curing temperature of the resin. That is, since the intermetallic compound contains a metal having a melting point lower than the curing temperature of the resin, the metal having a melting point lower than the curing temperature of the resin melts during the drying and curing processes, forms a part of the metal particles and an intermetallic compound, and comes to surround the metal particles. At this time, the intermetallic compound can preferably contain a low melting point metal of 300°C or lower.

[0095] For example, the intermetallic compound can contain Sn having a melting point of 213 to 220°C. During the drying and curing processes, Sn melts, and the molten Sn wets high melting point metal particles such as Ag, Ni, or Cu by capillary action and reacts with a part of the Ag, Ni, or Cu metal particles to form 3 Sn, Ni 3 Sn 4 , Cu 6 Sn 5 , Cu 3 intermetallic compounds such as Sn. Ag, Ni, or Cu that did not participate in the reaction remain in the form of metal particles.

[0096] Therefore, the plurality of second conductive metal particles contain one or more of Ag, Ni, and Cu, and the intermetallic compound contains one or more of 3 Sn, Ni 3 Sn 4 , Cu 6 Sn 5 and Cu 3 Sn.

[0097] The plating layers 131c and 132c can play a role in improving the mounting characteristics.

[0098] The types of the plating layers 131c and 132c are not particularly limited, and may be single-layer plating layers 131c and 132c containing one or more of nickel (Ni), tin (Sn), silver (Ag), palladium (Pd), and alloys thereof, or may be formed of a plurality of layers.

[0099] More specific examples of the plating layers 131c and 132c may be that the plating layers 131c and 132c may be Ni plating layers or Sn plating layers, or may be in a form in which a Ni plating layer and a Sn plating layer are sequentially formed on the electrode layer, or may be in a form in which a Sn plating layer, a Ni plating layer, and a Sn plating layer are sequentially formed. Further, the plating layers 131c and 132c may include a plurality of Ni plating layers and / or a plurality of Sn plating layers.

[0100] The size of the multilayer electronic component 100 does not particularly need to be limited.

[0101] However, in order to simultaneously achieve miniaturization and high capacitance, since the thicknesses of the dielectric layer and the internal electrodes need to be reduced and the number of layers needs to be increased, the effects according to the present invention can be more remarkable in the multilayer electronic component 100 having a size of 3216 (length × width: 3.2 mm × 1.6 mm) or less.

[0102] Hereinafter, various embodiments of the present invention will be described more specifically.

[0103] Multilayer electronic components must have excellent reliability so that they can operate smoothly even in harsh environments such as high temperature, high pressure, and high voltage. To solve this problem, the reliability is improved by adding rare earth elements. More specifically, the mechanism of "deterioration", which is directly related to reliability, is affected by the movement of oxygen vacancies. To suppress such deterioration, the concentration of oxygen vacancies itself can be reduced to prevent the degradation of insulation resistance in a high-temperature environment. To minimize the degradation of insulation resistance, a microstructure such as crystal grains with a core-shell structure containing rare earth elements at a certain ratio or more is realized to improve the reliability of multilayer ceramic capacitors. However, if rare earth elements are added excessively, problems such as a decrease in dielectric constant or failure to meet the target temperature coefficient of capacitance (TCC) characteristics may occur. Since rare earth elements are quite expensive, there is a drawback of being uneconomical.

[0104] And "burnt", which is one of such deteriorations, is likely to occur near the interface between the capacitance forming part and the cover part for protecting the capacitance forming part, which may reduce the reliability of the multilayer electronic component.

[0105] In the case of the dielectric layer disposed in the adjacent regions of the cover portions 112 and 113 (the region of the outer portion described later) rather than the dielectric layer disposed in the central portion of the capacitance forming portion Ac (the region of the inner portion described later), while a voltage is being applied, the dielectric layer can be further expanded in the second direction (length direction), and the size (thickness) of the dielectric layer in the third direction can be further decreased. As a result, by increasing the voltage applied per unit thickness (V / μm), a voltage higher than the breakdown voltage (BDV) can be applied, and as a result, deterioration can more easily occur in the dielectric layer disposed in the adjacent regions of the cover portions 112 and 113 (the region of the outer portion described later) of the capacitance forming portion Ac.

[0106] Here, "burnt" can mean a phenomenon in which due to excessive electrical stress applied to the multilayer electronic component, a high current flows inside the multilayer electronic component, and a partial region of the main body 110 cracks or burns and discolors due to high-temperature heating of the multilayer electronic component.

[0107] In one embodiment of the present invention, the capacitance forming portion Ac includes an inner portion 141 located at the center of the capacitance forming portion Ac in the first direction, and an outer portion 142 located between the inner portion 141 and the cover portions 112 and 113. When the average number of moles of rare earth elements per 100 moles of titanium (Ti) contained in the inner portion 141 is RE1, the average number of moles of rare earth elements per 100 moles of titanium (Ti) contained in the outer portion 142 is RE2, and the average number of moles of rare earth elements per 100 moles of titanium (Ti) contained in the cover portions 112 and 113 is RE3, RE1 < RE2 and RE3 < RE2 can be satisfied.

[0108] In the present invention, any rare earth element may be used as long as it can improve the reliability of the multilayer electronic component. For example, it can include at least one of dysprosium (Dy) and terbium (Tb).

[0109] The average number of moles of rare earth elements (RE2) per 100 moles of titanium (Ti) contained in the outer portion 142 is greater than the average number of moles of rare earth elements (RE1) per 100 moles of titanium (Ti) contained in the inner portion 141 (RE1 < RE2), and the average number of moles of rare earth elements (RE2) per 100 moles of titanium (Ti) contained in the outer portion 142 is greater than the average number of moles of rare earth elements (RE3) per 100 moles of titanium (Ti) contained in the cover portions 112 and 113. As a result, deterioration that is likely to occur near the interface between the capacitance forming portion and the cover portion for protecting the capacitance forming portion can be suppressed, and thereby the reliability of the multilayer electronic component can be improved.

[0110] Further, by adding a trace amount of rare earth elements to the inner portion 141 or the cover portions 112 and 113, or adding almost no rare earth elements, the dielectric properties of the multilayer electronic component can be improved or the dielectric loss can be reduced, and there can also be an advantage of being economical.

[0111] When the average number of moles of rare earth elements (RE2) per 100 moles of titanium (Ti) contained in the outer portion 142 is less than or equal to the average number of moles of rare earth elements (RE1) per 100 moles of titanium (Ti) contained in the inner portion 141 (RE2 ≦ RE1), or when the average number of moles of rare earth elements (RE2) per 100 moles of titanium (Ti) contained in the outer portion 142 is less than or equal to the average number of moles of rare earth elements (RE3) per 100 moles of titanium (Ti) contained in the cover portions 112 and 113 (RE2 ≦ RE3), it may be difficult to effectively prevent the deterioration that appears in the outer portion 142, which is near the interface with the cover portions 112 and 113, of the capacitance forming portion Ac, and there is a possibility that the reliability of the multilayer electronic component 100 may decrease.

[0112] In the present invention, as an example of a more specific method for measuring the content of elements included in each component of the multilayer electronic component 100, in the case of a destructive method, in the energy dispersive X-ray spectroscopy (EDS) mode of a scanning electron microscope (SEM), the EDS mode of a transmission electron microscope (TEM), or the EDS mode of a scanning transmission electron microscope (STEM), the components can be analyzed. For example, in a region including a dielectric microstructure in a cross-section of a sintered body or a side margin portion, an analysis sample thinned using a focused ion beam (FIB) equipment is prepared. Then, for the thinned sample, the damaged layer on the surface is removed using xenon (Xe) or argon (Ar) ion milling, and then, the components to be measured are mapped using an image obtained by SEM-EDS, TEM-EDS, or STEM-EDS for qualitative / quantitative analysis. In this case, the qualitative / quantitative analysis graph of each component can also be expressed by converting it into the mass percentage (wt%), atomic percentage (at%), or molar percentage (mol%) of each element. At this time, the molar number of one specific component with respect to the molar number of another specific component can be converted and expressed. For example, it can be expressed by the molar number of a rare earth element with respect to 100 moles of titanium (Ti).

[0113] As yet another method, the chip is pulverized to select a region including a dielectric microstructure, and for the portion including the dielectric microstructure thus selected, a device such as an inductively coupled plasma optical emission spectrometer (ICP-OES) or an inductively coupled plasma mass spectrometer (ICP-MS) can be used to analyze the components of the region including the dielectric microstructure.

[0114] As described above, the cover portions 112 and 113 can include a first cover portion 112 disposed on one end surface in the first direction of the capacitance forming portion Ac and a second cover portion 113 disposed on the other end surface in the first direction of the capacitance forming portion Ac.

[0115] Also, the outer portion 142 can include a first outer portion 142-1 located between the inner portion 141 and the first cover portion 112, and a second outer portion 142-2 located between the inner portion 141 and the second cover portion 113.

[0116] At this time, the average size of the outer portion 142 in the first direction may be 30% or less of the average size of the capacitance forming portion Ac in the first direction. More specifically, the average size of each of the first and second outer portions 142-1 and 142-2 in the first direction may be 15% or less of the average size of the capacitance forming portion Ac in the first direction.

[0117] For example, when the average size of the capacitance forming portion Ac excluding the cover portions 112 and 113 in the first direction is Ta, the average size of the inner portion 141 in the first direction is T1, and the average size of the outer portion 142 in the first direction is T2, based on the cross-sections of the main body 110 in the first and second directions, the ratio (T2 / Ta) of the average size T2 of the outer portion in the first direction to the average size Ta of the capacitance forming portion in the first direction can be 30% or less when expressed as a percentage. More specifically, when the average size of the first outer portion 142-1 in the first direction is T2-1 and the average size of the second outer portion 142-2 in the first direction is T2-2, the ratio (T2-1 / Ta) of the average size T2-1 of the first outer portion 142-1 in the first direction to the average size Ta of the capacitance forming portion Ac in the first direction can be 15% or less when expressed as a percentage, and the ratio T2-2 / Ta of the average size T2-2 of the second outer portion 142-2 in the first direction to the average size Ta of the capacitance forming portion Ac in the first direction can be 15% or less when expressed as a percentage. In the present invention, T2-1 which is the average size of the first outer portion 142-1 in the first direction and T2-2 which is the average size of the second outer portion 142-2 in the first direction do not mean mathematical expressions but characters.

[0118] The average sizes T2-1 and T2-2 in the first direction of the first and second outer portions 142-1 and 142-2 respectively satisfy being 15% or less of the average size Ta in the first direction of the capacitance forming portion Ac, so that deterioration mainly occurring near the interface between the capacitance forming portion Ac and the cover portions 112 and 113 can be more effectively suppressed, and the reliability can be improved.

[0119] When the average sizes T2-1 and T2-2 in the first direction of the first and second outer portions 142-1 and 142-2 respectively exceed 15% of the average size Ta in the first direction of the capacitance forming portion Ac, there is a possibility that the dielectric characteristics may deteriorate.

[0120] On the other hand, in one embodiment of the present invention, the average number of moles (RE2) of the rare earth element with respect to 100 moles of titanium (Ti) contained in the outer portion 142 can be 1 mole or more and 5 moles or less. In other words, it can satisfy 1 mole ≤ RE2 ≤ 5 moles.

[0121] By the average number of moles (RE2) of the rare earth element with respect to 100 moles of titanium (Ti) contained in the outer portion 142 satisfying 1 mole or more and 5 moles or less, the grain growth of the crystal grains contained in the outer portion 142 can be suppressed, the expansion of the outer portion 142 in the second direction can be suppressed, and the decrease in the size (thickness) in the third direction can be prevented. The voltage (V / μm) applied per unit thickness can be decreased, and the occurrence of deterioration in the outer portion 142 can be more effectively suppressed, so that the reliability can be improved.

[0122] When the average number of moles of rare earth elements (RE2) per 100 moles of titanium (Ti) contained in the outer portion 142 is less than 1 mole, due to excessive grain growth of the crystal grains contained in the outer portion 142, the size (thickness) in the third direction decreases due to the expansion of the outer portion 142 in the second direction, making it difficult to suppress the occurrence of deterioration, and there is a possibility that the reliability may decrease. When the average number of moles of rare earth elements (RE2) per 100 moles of titanium (Ti) contained in the outer portion 142 exceeds 5 moles, there is a risk that the dispersibility may decrease due to the addition of excessive rare earth elements, or the grain growth of the crystal grains may be excessively suppressed, resulting in a decrease in dielectric properties.

[0123] Also, the difference (RE2 - RE1) between the average number of moles of rare earth elements (RE2) per 100 moles of titanium (Ti) contained in the outer portion 142 and the average number of moles of rare earth elements (RE1) per 100 moles of titanium (Ti) contained in the inner portion 141 can be 0.1 mole or more and 5 moles or less. In other words, it can satisfy 0.1 mole ≤ RE2 - RE1 ≤ 5 moles.

[0124] By satisfying that the difference (RE2 - RE1) between the average number of moles of rare earth elements (RE2) per 100 moles of titanium (Ti) contained in the outer portion 142 and the average number of moles of rare earth elements (RE1) per 100 moles of titanium (Ti) contained in the inner portion 141 is 0.1 mole or more and 5 moles or less, a decrease in reliability can be prevented.

[0125] When the difference (RE2 - RE1) between the average number of moles of rare earth elements (RE2) per 100 moles of titanium (Ti) contained in the outer portion 142 and the average number of moles of rare earth elements (RE1) per 100 moles of titanium (Ti) contained in the inner portion 141 is less than 0.1 mole, the effect of suppressing the expansion in the second direction of the outer portion 142 is insufficient, the size (thickness) in the third direction decreases, the applied voltage per unit thickness (V / μm) becomes high, and there is a risk of a decrease in reliability. When the difference (RE2 - RE1) between the average number of moles of rare earth elements (RE2) per 100 moles of titanium (Ti) contained in the outer portion 142 and the average number of moles of rare earth elements (RE1) per 100 moles of titanium (Ti) contained in the inner portion 141 exceeds 5 moles, the dispersibility may decrease due to the excessive addition of rare earth elements in the outer portion 142, a sintering difference may occur between the inner portion 141 and the outer portion 142, and there is a risk of cracks due to sintering delay.

[0126] Referring to FIG. 6, in which a line-profile is performed along the LP-LP' line in FIG. 5 to show the content of rare earth elements in a graph, the content of rare earth elements may change abruptly at the interfaces between the cover portions 112 and 113 and the outer portions 142-1 and 142-2, and may also change abruptly at the interfaces between the outer portions 142-1 and 142-2 and the inner portion 141. In this way, the inner portion 141, the outer portions 142-1 and 142-2, and the cover portions 112 and 113 can be divided based on the points where the content of rare earth elements changes abruptly, but it is not particularly limited thereto. Here, the content of rare earth elements is preferably atomic percentage (at%), but may also correspond to mass percentage (wt%), molar percentage (mol%), or the number of moles of rare earth elements per 100 moles of titanium (Ti).

[0127] In one embodiment of the present invention, the inner portion 141 may not contain rare earth elements. For example, the number of moles of rare earth elements (RE1) per 100 moles of titanium (Ti) contained in the inner portion 141 may be less than 0.1 mole, or the atomic percentage (at%) of rare earth elements contained in the inner portion 141 may be less than 0.5 at%.

[0128] Even if the inner part 141 does not contain rare earth elements, the outer part 142 contains rare earth elements, so that the reliability of the multilayer electronic component can be improved, the target TCC characteristics can be satisfied, the moisture resistance reliability can be excellent, and the advantage of being economical can be accompanied.

[0129] As described above, the inner part 141 and the outer part 142 contain dielectric crystal grains, and the average size of the dielectric crystal grains contained in the outer part 142 can be smaller than the average size of the dielectric crystal grains contained in the inner part 141.

[0130] This is because rare earth elements can play a role in controlling the grain growth of dielectric crystal grains. However, when the number of moles of rare earth elements (RE2) contained in the outer part 142 is larger than the number of moles of rare earth elements (RE1) contained in the inner part 141, the grain growth of the dielectric crystal grains contained in the outer part 142 can be suppressed, and the average size of the dielectric crystal grains contained in the inner part 141 can be smaller than the average size of the dielectric crystal grains contained in the outer part 142.

[0131] The method for measuring the average size of the dielectric crystal grains of the inner part 141 and the outer part 142 is, for example, based on the cross-sections in the first and second directions of the main body including the capacitance forming part, and the size of the dielectric crystal grains contained in the 5μm×5μm region of the cross-section of the inner part is measured and averaged for calculation. The size of the dielectric crystal grains contained in the 5μm×5μm region of the cross-section of the outer part can be measured and averaged for calculation, but it is not particularly limited thereto. Here, the size of the dielectric crystal grains can mean the maximum diameter or the minimum diameter of the dielectric crystal grains, or can correspond to the average value of the maximum diameter and the minimum diameter.

[0132] When the average size of the dielectric crystal grains contained in the outer part 142 is smaller than the average size of the dielectric crystal grains contained in the inner part 141, the dielectric crystal grain boundaries in the outer part 142 increase, and the breakdown voltage (BDV) due to the electric field concentration phenomenon can be suppressed, and the reliability can be improved.

[0133] Further, the average number of pores in the outer portion 142 can be less than the average number of pores in the inner portion 141. Here, the average number of pores in the outer portion 142 can be a value obtained by averaging the numbers of pores in the first and second outer portions 142-1 and 142-2, respectively.

[0134] A method for measuring the average number of pores in the inner portion 141 and the outer portion 142 is, for example, based on cross-sections in the first and second directions of the main body including the capacitance forming portion, measuring the number of pores included in a 5 μm × 5 μm region of the inner portion, expanding this measurement to other regions of the inner portion, and then calculating the average. Similarly, the number of pores included in a 5 μm × 5 μm region of the cross-sections of the first and second outer portions can be measured, expanded to other regions of the first and second outer portions, and then averaged and calculated, but it is not particularly limited thereto.

[0135] When the average number of moles of rare earth elements (RE2) per 100 moles of titanium (Ti) contained in the outer portion 142 is more than the average number of moles of rare earth elements (RE1) per 100 moles of titanium (Ti) contained in the inner portion 141, the grain growth of the dielectric crystal grains contained in the outer portion 142 can be controlled to suppress the generation of pores, and thereby, the average number of pores contained in the outer portion 142 can be less than the average number of pores contained in the inner portion 141.

[0136] When the average number of pores in the outer portion 142 is less than the average number of pores in the inner portion 141, the number of pores in the outer portion 142 region where moisture penetration from the outside is easy decreases, so that the moisture resistance reliability of the multilayer electronic component 100 can be improved.

[0137] On the other hand, in one embodiment of the present invention, the average number of moles of rare earth elements (RE2a) per 100 moles of titanium (Ti) contained in the first outer portion 142-1 can be more than the average number of moles of rare earth elements (RE2b) per 100 moles of titanium (Ti) contained in the second outer portion 142-2, in other words, RE2b < RE2a can be satisfied.

[0138] Both the first outer part 141-1 and the second outer part 141-2 correspond to regions where deterioration frequently occurs. However, deterioration may occur more frequently in the region of the first outer part 141-1 than in the second outer part 141-2. Therefore, by adding more rare earth elements to the first outer part 141-1 than to the second outer part 141-2, the occurrence of deterioration can be suppressed and the reliability can be improved.

[0139] Referring to FIG. 7 which shows the content of rare earth elements in a graph by performing a line-profile along the LP-LP' line in FIG. 5, the content of rare earth elements may change abruptly at the boundary surfaces between the cover parts 112, 113 and the outer parts 142-1, 142-2, and may also change abruptly at the boundary surfaces between the outer parts 142-1, 142-2 and the inner part 141. At this time, the content of rare earth elements in the first outer part 142-1 can be more than the content of rare earth elements in the second outer part 142-2. More specifically, the maximum content or average content of rare earth elements in the first outer part 142-1 can be more than the maximum content or average content of rare earth elements in the second outer part 142-2. In this way, starting from the point where the content of rare earth elements changes abruptly, the inner part 141, the outer parts 142-1, 142-2, and the cover parts 112, 113 can be divided, but it is not particularly limited thereto. Here, the content of rare earth elements is preferably atomic percentage (at%), but can correspond to mass percentage (wt%), molar percentage (mol%), or the number of moles of rare earth elements relative to 100 moles of titanium (Ti).

[0140] Also, the average size of the dielectric crystal grains contained in the first outer part 142-1 can be smaller than the average size of the dielectric crystal grains contained in the second outer part 142-2.

[0141] Although rare earth elements can play a role in controlling the grain growth of dielectric crystallites, when the average number of moles of rare earth elements (RE2a) per 100 moles of titanium (Ti) contained in the first outer portion 142-1 is greater than the average number of moles of rare earth elements (RE2b) per 100 moles of titanium (Ti) contained in the second outer portion 142-2, the grain growth of the dielectric crystallites contained in the first outer portion 142-1 can be more effectively suppressed, and the average size of the dielectric crystallites contained in the first outer portion 142-1 can be smaller than the average size of the dielectric crystallites contained in the second outer portion 142-2.

[0142] When the average size of the dielectric crystallites contained in the first outer portion 142-1 is smaller than the average size of the dielectric crystallites contained in the second outer portion 142-2, the number of dielectric crystal grain boundaries in the first outer portion 142-1 increases, and the breakdown voltage (BDV) due to the electric field concentration phenomenon can be more effectively suppressed, and the reliability can be further improved.

[0143] Also, the number of pores in the first outer portion 142-1 can be less than the number of pores in the second outer portion 142-2.

[0144] When the average number of moles of rare earth elements (RE2a) per 100 moles of titanium (Ti) contained in the first outer portion 142-1 is greater than the average number of moles of rare earth elements (RE2b) per 100 moles of titanium (Ti) contained in the second outer portion 142-2, the grain growth of the dielectric crystallites contained in the first outer portion 142-1 can be more easily controlled to suppress the generation of pores, and thereby, the number of pores contained in the first outer portion 142-1 can be less than the number of pores contained in the second outer portion 142-2.

[0145] When the number of pores contained in the first outer portion 142-1 is less than the number of pores contained in the second outer portion 142-2, the moisture resistance reliability of the first outer portion 142-1, which is more vulnerable to moisture penetration from the outside than the second outer portion 142-2 close to the mounting surface, can be improved, and the moisture resistance reliability of the multilayer electronic component 100 can be further improved.

[0146] On the one hand, in one embodiment of the present invention, the average number of moles of rare earth elements (RE3) per 100 moles of titanium (Ti) contained in the cover portions 112 and 113 can be more than the average number of moles of rare earth elements (RE1) per 100 moles of titanium (Ti) contained in the inner portion 141. In other words, RE1 < RE3 can be satisfied.

[0147] As described above, in the case of the cover portions 112 and 113, they can play a role in protecting the internal electrodes 121 and 122 contained in the capacitance forming portion Ac. By adding rare earth elements to the cover portions 112 and 113, the grain growth of dielectric crystal grains can be more easily controlled, the breakdown voltage (BDV) due to the electric field concentration phenomenon can be improved, and the number of pores can be suppressed to further improve the moisture resistance reliability.

[0148] In other words, the average size of the dielectric crystal grains contained in the cover portions 112 and 113 can be smaller than the average size of the dielectric crystal grains contained in the inner portion 141.

[0149] The effect due to the size of the dielectric crystal grains is the same as described above, so it is omitted.

[0150] Also, the number of pores contained in the cover portions 112 and 113 can be less than the number of pores contained in the inner portion 141.

[0151] The effect due to the number of pores is the same as described above, so it is omitted.

[0152] As described above, the embodiments of the present invention have been described in detail. However, the present invention is not limited by the above-described embodiments and the accompanying drawings, but is limited by the appended claims. Therefore, within the scope not departing from the technical idea of the present invention described in the claims, various forms of substitution, modification, and change are possible by those with ordinary knowledge in the technical field, and it can be said that these also belong to the scope of the present invention.

[0153] In addition, the expression "one embodiment" used in the present invention does not mean the same embodiment, but is provided to emphasize and explain each unique feature that is different from each other. However, the one embodiment presented above does not exclude being realized in combination with the features of other embodiments. For example, even if the matter described in a specific embodiment is not described in other embodiments, it can be understood as an explanation related to other embodiments as long as there is no explanation contrary to or conflicting with that matter in other embodiments.

[0154] The terms used in the present invention are merely used to explain one embodiment and are not intended to limit the present invention. At this time, the singular expression includes plural expressions unless the context clearly indicates a different meaning.

Description of Reference Numerals

[0155] 100: Multilayer electronic component 110: Body 111: Dielectric layer 112, 113: Cover part 114, 115: Side margin part 121, 122: Internal electrode 131, 132: External electrode 141: Inner part 142: Outer part

Claims

1. a capacitance forming portion including dielectric layers and internal electrodes arranged alternately with the dielectric layers in a first direction, and a body including cover portions arranged on both end surfaces of the capacitance forming portion in the first direction; an external electrode disposed on the body; the capacitance generating portion includes an inner portion located at a center portion of the capacitance generating portion in the first direction, and an outer portion located between the inner portion and the cover portion, Let RE1 be the average number of moles of rare earth elements per 100 moles of titanium (Ti) contained in the inner portion, RE2 be the average number of moles of rare earth elements per 100 moles of titanium (Ti) contained in the outer portion, and RE3 be the average number of moles of rare earth elements per 100 moles of titanium (Ti) contained in the cover portion. A multilayer electronic component that satisfies RE1<RE2 and RE3<RE2.

2. the cover portion includes a first cover portion disposed on one end surface of the capacitance generating portion in the first direction and a second cover portion disposed on the other end surface of the capacitance generating portion in the first direction, the outer portion includes a first outer portion located between the inner portion and the first cover portion and a second outer portion located between the inner portion and the second cover portion, 2 . The multilayer electronic component according to claim 1 , wherein an average size in the first direction of each of the first and second outer portions is 15% or less of an average size in the first direction of the capacitance forming portion.

3. 2. The multilayer electronic component according to claim 1, wherein the RE2 satisfies 1 mol≦RE2≦5 mol.

4. 2. The multilayer electronic component according to claim 1, wherein the difference between RE2 and RE1 (RE2-RE1) satisfies 0.1 mol≦RE2-RE1≦5 mol.

5. 2. The multilayer electronic component according to claim 1, wherein the average atomic percentage of the rare earth element contained in the inner portion is less than 0.5 at %.

6. When the average mole number of rare earth elements per 100 moles of titanium (Ti) contained in the first outer portion is RE2a and the average mole number of rare earth elements per 100 moles of titanium (Ti) contained in the second outer portion is RE2b, The multilayer electronic component according to claim 2 , wherein RE2b<RE2a is satisfied.

7. the inner and outer portions include dielectric grains; 2. The multilayer electronic component according to claim 1, wherein an average size of the dielectric crystal grains included in the outer portion is smaller than an average size of the dielectric crystal grains included in the inner portion.

8. The multilayer electronic component according to claim 1 , wherein an average number of pores in the outer portion is less than an average number of pores in the inner portion.

9. the first and second outer portions include dielectric grains; 3. The multilayer electronic component according to claim 2, wherein an average size of the dielectric crystal grains included in the first outer portion is smaller than an average size of the dielectric crystal grains included in the second outer portion.

10. The multilayer electronic component according to claim 2 , wherein an average number of pores in the first outer portion is less than an average number of pores in the second outer portion.

11. The multilayer electronic component according to claim 1 , wherein RE1 and RE3 satisfy RE1<RE3.

12. 2. The multilayer electronic component according to claim 1, wherein the rare earth element is at least one of dysprosium (Dy) and terbium (Tb).

13. The multilayer electronic component according to claim 1 , wherein the body includes a plurality of internal electrodes, and adjacent ones of the plurality of internal electrodes include regions that protrude toward each other in the first direction.

14. The multilayer electronic component according to claim 1 , wherein the body includes a plurality of dielectric layers, and at least one of the plurality of dielectric layers has an average size in the first direction of 1.0 μm or less.

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