Ceramic electronic component

Abstract

To provide a ceramic electronic component having excellent reliability even in a severe environment.SOLUTION: A ceramic electronic component includes: a main body including a dielectric layer 111 and internal electrodes alternately disposed with the dielectric layers; and an external electrode disposed on the main body. The dielectric layer include a plurality of crystal grains 111a and crystal grain boundaries 111b disposed between adjacent crystal grains. When the number of moles of a rare earth element with respect to 100 moles of Ti contained in the dielectric layer is MRe and the number of moles of Si is MSi, 1.6≤MRe / MSi≤4.0 is satisfied, and when an average Si content contained in the crystal grains is GSi and the maximum value of the Si content in the crystal grain boundaries is BSi, 2.0≤BSi / GSi is satisfied.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to ceramic electronic components.

Background Art

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

[0003] Due to the advantages of being small in size while ensuring high capacitance and being easy to mount, multilayer ceramic capacitors can be used as components of various electronic devices. As various electronic devices such as computers and mobile devices are miniaturized and have increased output, the requirements for miniaturization and high capacitance of multilayer ceramic capacitors are increasing.

[0004] In order to achieve miniaturization and high capacitance of multilayer ceramic capacitors, it is necessary to reduce the thickness of the dielectric layer and the internal electrodes and increase the number of layers. However, the thinner the dielectric layer, the greater the electric field applied to the dielectric at the same operating voltage, so ensuring the reliability of the dielectric is essential.

Summary of the Invention

Problems to be Solved by the Invention

[0005] One of several objects of the present invention is to provide a ceramic electronic component with excellent reliability.

[0006] One of several objects of the present invention is to provide a ceramic electronic component with excellent reliability even under harsh environments.

[0007] However, the object of the present invention is not limited to the above-described content and can be more easily understood in the process of explaining the specific embodiments of the present invention.

Means for Solving the Problems

[0008] A ceramic electronic component according to an embodiment of the present invention includes a main body including a dielectric layer and internal electrodes alternately arranged with the dielectric layer, and external electrodes arranged on the main body. The dielectric layer includes a plurality of crystal grains and grain boundaries arranged between adjacent crystal grains. When the number of moles of a rare earth element with respect to 100 moles of Ti contained in the dielectric layer is MRe and the number of moles of Si is MSi, 1.6 ≦ MRe / MSi ≦ 4.0 is satisfied. When the average Si content contained in the crystal grains is GSi and the maximum value of the Si content at the grain boundaries is BSi, 2.0 ≦ BSi / GSi can be satisfied.

Effects of the Invention

[0009] One of the effects of the present invention is that the reliability of the ceramic electronic component is improved by adjusting the ratio of Si to the rare earth element contained in the dielectric layer and the distribution of Si.

[0010] However, the various 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 the specific embodiments of the present invention.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Embodiments for Carrying Out the Invention

[0012] Hereinafter, embodiments of the present invention will be described with reference to specific embodiments and the accompanying drawings. However, the embodiments of the present invention can be modified into various other forms, and the scope of the present invention is not limited to the embodiments described below. Also, the embodiments of the present invention are provided to more fully explain the present invention to an ordinary technician. 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.

[0013] 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. For components having the same function within the scope of the same concept, the same reference numerals are used for explanation. Furthermore, throughout the specification, when a certain 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.

[0014] 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.

[0015] Ceramic electronic component FIG. 1 schematically shows a perspective view of a ceramic electronic component according to an embodiment of the present invention. FIG. 2 schematically shows a cross-sectional view taken along line I-I' of FIG. 1. FIG. 3 schematically shows a cross-sectional view taken along line II-II' of FIG. 1. FIG. 4 is a perspective view schematically showing the disassembled body of FIG. 1. FIG. 5 is an enlarged view of the K1 region of FIG. 2. FIG. 6 is an image obtained by scanning the K1 region of FIG. 2 with a scanning electron microscope (SEM). FIG. 7 is a graph obtained by performing a line-profile along the L1 line of FIG. 6.

[0016] Hereinafter, with reference to FIGS. 1 to 7, a ceramic electronic component 100 according to an embodiment of the present invention will be described in detail. Further, as an example of the ceramic electronic component, a multilayer ceramic capacitor (hereinafter referred to as "MLCC") will be described, but the present invention is not limited thereto, and it can also be applied to various ceramic electronic components using a ceramic material, such as an inductor, a piezoelectric element, a varistor, or a thermistor.

[0017] A ceramic electronic component 100 according to an embodiment of the present invention includes a body 110 including a dielectric layer 111 and internal electrodes 121 and 122 alternately arranged with the dielectric layer, and external electrodes 131 and 132 arranged on the body. The dielectric layer includes a plurality of crystal grains 111a and grain boundaries 111b arranged between adjacent crystal grains. When the number of moles of a rare earth element with respect to 100 moles of Ti contained in the dielectric layer is MRe and the number of moles of Si is MSi, 1.6 ≤ MRe / MSi ≤ 4.0 is satisfied. When the average Si content contained in the crystal grains is GSi and the maximum value of the Si content at the grain boundaries is BSi, 2.0 ≤ BSi / GSi can be satisfied.

[0018] Hereinafter, each component included in the ceramic electronic component 100 according to an embodiment of the present invention will be described.

[0019] The body 110 may have the dielectric layer 111 and the internal electrodes 121 and 122 alternately laminated.

[0020] There is no particular limitation on the specific shape of the main body 110. However, as shown in the figure, the main body 110 can be formed in a hexahedron shape or a shape similar thereto. Due to the shrinkage of the ceramic powder contained in the main body 110 during the firing process, the main body 110 does not have a hexahedron shape with perfect straight lines, but can have a substantially hexahedron shape.

[0021] The main body 110 can have a first surface 1 and a second surface 2 facing each other in a first direction, a third surface 3 and a fourth surface 4 connected to the first surface 1 and the second surface 2 and facing each other in a second direction, and a fifth surface 5 and a sixth surface 6 connected to the first surface 1 and the second surface 2 and to the third surface 3 and the fourth surface 4 and facing each other in a third direction. The first surface 1 may be a mounting surface arranged to face the substrate when mounted on the substrate.

[0022] By overlapping the margin areas where the internal electrodes 121 and 122 are not arranged on the dielectric layer 111, a step due to the thickness of the internal electrodes 121 and 122 is generated, and the corners connecting the first surface to the third to fifth surfaces and / or the corners connecting the second surface to the third to fifth surfaces can have a form shrunk toward the central side of the main body 110 in the first direction when viewed with reference to the first surface or the second surface. Alternatively, due to the shrinkage behavior during the sintering process of the main body, the corners connecting the first surface 1 to the third to sixth surfaces 3, 4, 5, 6 and / or the corners connecting the second surface 2 to the third to sixth surfaces 3, 4, 5, 6 can have a form shrunk toward the central side of the main body 110 in the first direction when viewed with reference to the first surface or the second surface. Alternatively, in order to prevent chipping defects or the like, by performing a separate process to round the corners connecting the respective surfaces of the main body 110, the corners connecting the first surface to the third to sixth surfaces and / or the corners connecting the second surface to the third to sixth surfaces can have a rounded form.

[0023] On the other hand, in order to suppress the step formed by the internal electrodes 121 and 122, after cutting such that the internal electrodes after lamination are exposed on the fifth and sixth surfaces 5 and 6 of the main body, when a single dielectric layer or two or more dielectric layers are laminated in the third direction (width direction) on both side surfaces of the capacitance forming portion Ac to form the margin portions 114 and 115, the portions connecting the first surface to the fifth and sixth surfaces, and the portions connecting the second surface to the fifth and sixth surfaces do not necessarily have a shrunk form.

[0024] The plurality of dielectric layers 111 forming the main body 110 are in a fired state, and the boundaries between adjacent dielectric layers 111 can be integrated to such an extent that they are difficult to confirm without using a scanning electron microscope (SEM). The number of laminated dielectric layers is not particularly limited and can be determined in consideration of the size of the ceramic electronic component. For example, the main body can be formed by laminating 400 or more dielectric layers.

[0025] The dielectric layer 111 can be formed by manufacturing a ceramic slurry containing ceramic powder, an organic solvent, and a binder, applying and drying the slurry on a carrier film to provide a ceramic green sheet, and then firing the ceramic green sheet. The ceramic powder is not particularly limited as long as sufficient capacitance can be obtained. For example, as the ceramic powder, barium titanate (BaTiO3)-based powder can be used. More specifically, the ceramic powder 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).

[0026] Therefore, in one embodiment, the dielectric layer 111 can contain, as a main component, 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).

[0027] More preferably, the dielectric layer 111 can contain BaTiO3 as a main component.

[0028] The dielectric layer 111 includes a plurality of crystal grains 111a and grain boundaries 111b disposed between adjacent crystal grains. When the number of moles of rare earth elements with respect to 100 moles of Ti contained in the dielectric layer is MRe and the number of moles of Si is MSi, 1.6 ≤ MRe / MSi ≤ 4.0 is satisfied. When the average Si content in the crystal grains is GSi and the maximum value of the Si content at the grain boundaries is BSi, 2.0 ≤ BSi / GSi can be satisfied.

[0029] A multilayer ceramic capacitor (MLCC), which is one type of ceramic electronic component, tends to have higher capacitance and thinner layers. In order to achieve thinning of the dielectric layer, basically, a technique is required to reduce the size of dielectric crystal grains and increase the grain boundary resistance of the dielectric crystal grains to suppress basic charge movement.

[0030] The Si element has a large energy bandgap and excellent electrical insulation effect. According to an embodiment of the present invention, by adjusting the ratio of the Si element to the rare earth element contained in the dielectric layer 111 and adjusting the distribution of the Si element in the crystal grains 111a and the grain boundaries 111b, the reliability of the ceramic electronic component 100 can be improved. Thereby, uniform crystal grains can be ensured, grain growth can be suppressed, and abnormal grain growth can be suppressed. Further, when Si is located at the grain boundary, the energy barrier can be increased, and the reduction of mobility due to the hopping or tunneling effect of charge carriers can be induced.

[0031] When the rare earth element is added to the main component of the barium titanate (BaTiO3) system, it can play a role in reducing the concentration of oxygen vacancies and improving the reliability by substituting the Ba-site and acting as a donor.

[0032] When 1.6 ≦ MRe / MSi ≦ 4.0 is not satisfied, or when BSi / GSi is less than 2.0, the above-described effects are insufficient, and the reliability may decrease.

[0033] At this time, the upper limit of BSi / GSi does not need to be particularly limited. For example, BSi / GSi may be 5.0 or less.

[0034] On the other hand, the method for controlling MRe / MSi and BSi / GSi is not particularly limited. For example, it can be controlled by adjusting the composition of the ceramic green sheet, the firing temperature during sintering, and the reducing atmosphere.

[0035] Referring to FIG. 5, the grain boundary 111b can be arranged in a form surrounding the crystal grain 111a.

[0036] In one embodiment, the number of moles of rare earth element (MRe) with respect to 100 moles of Ti contained in the dielectric layer 111 may be 0.1 mole or more and 6.0 moles or less.

[0037] In one embodiment, the number of moles of Si (MSi) with respect to 100 moles of Ti contained in the dielectric layer 111 may be 1.0 mole or more and 3.5 moles or less.

[0038] The average Si content (GSi) contained in the crystal grains 111a and the maximum value (BSi) of the Si content at the grain boundaries 111b are not particularly limited.

[0039] In one embodiment, the average Si content (GSi) contained in the crystal grains 111a may be 0.3 at% or more and 0.9 at% or less in atomic percentage.

[0040] In one embodiment, the maximum value (BSi) of the Si content at the grain boundaries 111b may be 1.5 at% or more and 3.5 at% or less.

[0041] In one embodiment, the rare earth element contained in the dielectric layer 111 may include one or more of Gd, La, Sm, Dy, Tb, Ho, Y, Yb, and Sc.

[0042] More preferably, the rare earth element contained in the dielectric layer 111 may include Dy and Y.

[0043] In one embodiment, the dielectric layer 111 further includes a first sub-component element, and the first sub-component element may be one or more of V, Zr, Mn, Cr, Ti, Ni, Co, and W.

[0044] Transition metal elements are elements having variable valence, which can play a role in reducing the firing temperature and improving the high-temperature breakdown voltage characteristics. Also, when added to the main component of barium titanate (BaTiO3), they can substitute the Ti-site.

[0045] More preferably, the first sub-component element may be V and Mn.

[0046] At this time, the dielectric layer 111 can contain the above first sub-component element in an amount of 0.5 mol or more and 3.0 mol or less with respect to 100 mol of Ti.

[0047] In one embodiment, the dielectric layer 111 further contains a second sub-component element, and the second sub-component element may be Mg. Mg can serve as a sintering aid element to facilitate sintering and control grain growth to form a core-shell structure.

[0048] At this time, the dielectric layer 111 can contain the above second sub-component element in an amount of 0.1 mol or more and 3.0 mol or less with respect to 100 mol of Ti.

[0049] In one embodiment, when the thickness of the grain boundary 111b is Tgb, Tgb may be 8.0 nm or more. Thereby, the effect of improving the reliability by controlling MRe / MSi and BSi / GSi can be further improved.

[0050] The upper limit of Tgb is not particularly limited. For example, Tgb can satisfy Tgb ≤ 15.0 nm. Therefore, in one embodiment, Tgb can satisfy 8.0 nm ≤ Tgb ≤ 15.0 nm.

[0051] The content of each element contained in the dielectric layer 111 can be analyzed for the components inside the dielectric grains at the center of the chip using TEM-EDS. Specifically, in a region including the dielectric layer in a cross-section of the sintered body, a thin analysis sample is prepared using a focused ion beam (FIB) equipment. Then, the damaged layer on the surface of the thinned sample is removed using Ar ion milling, and thereafter, mapping and quantitative analysis of each component are performed with the image obtained using TEM-EDS. In this case, the quantitative analysis graph of each component is obtained by the mass fraction of each element, but this can be converted and expressed as a molar fraction or an atomic fraction.

[0052] Further, after pulverizing the multilayer electronic component and removing the internal electrodes, the dielectric portions are sorted, and the components of the dielectric thus sorted can be analyzed using devices such as an inductively coupled plasma optical emission spectrometer (ICP-OES) and an inductively coupled plasma mass spectrometer (ICP-MS).

[0053] Also, the average Si content (GSi) contained in the crystal grains 111a, the maximum value of the Si content (BSi) at the crystal grain boundaries 111b, and the thickness (Tgb) of the crystal grain boundaries 111b can be measured by performing a line profile using a transmission electron microscope (TEM, Transmission Electron Microscope). Specifically, the central portions of the cross-sections in the first and second directions cut at the center in the third direction of the main body 110 are scanned with a transmission electron microscope (TEM) to obtain an image as shown in FIG. 6, and then the Si content (at%) is measured by a line profile along a 100-nm line L1 passing perpendicularly through the boundaries between the crystal grains, and a graph as shown in FIG. 7 can be obtained. In FIG. 7, the maximum Si content (at%) can be defined as BSi, the average Si content (at%) of the crystal grains can be defined as GSi, and the distance between the points reaching GSi on the left and right with the maximum Si content (at%) as a reference can be defined as the thickness (Tgb) of the crystal grain boundaries.

[0054] Also, in FIG. 6, after measuring the Si content (at%) by a line profile from 10 100-nm lines passing perpendicularly through the boundaries between the crystal grains to obtain BSi, GSi, and Tgb respectively, and calculating the average value, it can be further generalized.

[0055] The main body 110 includes a capacitance forming portion Ac that is disposed inside the main body 110 and in which a capacitance is formed by including a first internal electrode 121 and a second internal electrode 122 that are disposed to face each other with a dielectric layer 111 interposed therebetween, and cover portions 112 and 113 formed on the upper and lower portions in the first direction of the capacitance forming portion Ac.

[0056] Further, the capacitance forming portion Ac is a portion that contributes to the capacitance formation of the capacitor, and can be formed by repeatedly laminating a plurality of first and second internal electrodes 121 and 122 with the dielectric layer 111 interposed therebetween.

[0057] The cover portions 112 and 113 may include an upper cover portion 112 disposed above the capacitance forming portion Ac in the first direction and a lower cover portion 113 disposed below the capacitance forming portion Ac in the first direction.

[0058] The upper cover portion 112 and the lower cover portion 113 can be formed by laminating a single dielectric layer or two or more dielectric layers in the thickness direction on the upper and lower surfaces of the capacitance forming portion Ac, respectively, and can basically play a role of preventing damage to the internal electrodes due to physical or chemical stress.

[0059] The upper cover portion 112 and the lower cover portion 113 do not include internal electrodes and can include the same material as the dielectric layer 111.

[0060] That is, the upper cover portion 112 and the lower cover portion 113 can include a ceramic material, for example, a barium titanate (BaTiO3)-based ceramic material.

[0061] On the other hand, the thickness of the cover portions 112 and 113 does not need to be particularly limited. However, in order to more easily achieve miniaturization and high capacitance of the ceramic electronic component, the thickness tc of the cover portions 112 and 113 may be 15 μm or less.

[0062] The average thickness tc of the cover portions 112 and 113 can mean the size in the first direction, and can be a value obtained by averaging the sizes in the first direction of the cover portions 112 and 113 measured at five equally spaced points above or below the capacitance forming portion Ac.

[0063] Further, margin portions 114 and 115 may be disposed on the side surfaces of the capacitance forming portion Ac.

[0064] The margin portions 114 and 115 can include a first margin portion 114 disposed on the fifth surface 5 of the main body 110 and a second margin portion 115 disposed on the sixth surface 6. That is, the margin portions 114 and 115 may be disposed on both end surfaces in the width direction of the ceramic main body 110.

[0065] As shown in FIG. 3, the margin portions 114 and 115 can mean the regions between the boundaries of both ends of the first and second internal electrodes 121 and 122 and the main body 110 in the cross-section obtained by cutting the main body 110 in the width-thickness (W-T) direction.

[0066] The margin portions 114 and 115 can basically play a role in preventing damage to the internal electrodes due to physical or chemical stress.

[0067] The margin portions 114 and 115 may be formed by applying a conductive paste to form internal electrodes except for the locations where the margin portions are formed on the ceramic green sheet.

[0068] Also, in order to suppress the step difference caused by the internal electrodes 121 and 122, after cutting so that the internal electrodes after lamination are exposed on the fifth and sixth surfaces 5 and 6 of the main body, a single dielectric layer or two or more dielectric layers may be laminated in the third direction (width direction) on both side surfaces of the capacitance forming portion Ac to form the margin portions 114 and 115.

[0069] On the other hand, the width of the margin portions 114 and 115 does not need to be particularly limited. However, in order to more easily achieve miniaturization and high capacitance of the ceramic electronic component, the average width of the margin portions 114 and 115 may be 15 μm or less.

[0070] The average widths of the margin portions 114 and 115 can mean the average size MW1 in the third direction of the region where the internal electrodes are separated from the fifth surface and the average size MW2 in the third direction of the region where the internal electrodes are separated from the sixth surface, and can be the value obtained by averaging the sizes in the third direction of the margin portions 114 and 115 measured at five equally spaced points on the side surface of the capacitance forming portion Ac.

[0071] Therefore, in one embodiment, the average sizes MW1 and MW2 in the third direction of the regions where the internal electrodes 121 and 122 are separated from the fifth and sixth surfaces can be 15 μm or less respectively.

[0072] The internal electrodes 121 and 122 can include the first and second internal electrodes 121 and 122. The first and second internal electrodes 121 and 122 are alternately arranged so as to face each other with the dielectric layer 111 constituting the main body 110 interposed therebetween, and can be exposed on the third and fourth surfaces 3 and 4 of the main body 110 respectively.

[0073] The first internal electrode 121 can be exposed through the third surface 3 while being separated from the fourth surface 4, and the second internal electrode 122 can be exposed through the fourth surface 4 while being separated from the third surface 3. 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.

[0074] That is, the first internal electrode 121 is connected to the first external electrode 131 without being connected to the second external electrode 132, and the second internal electrode 122 is connected to the second external electrode 132 without being connected to the first external electrode 131. Therefore, the first internal electrode 121 can be formed at a certain distance apart on the fourth surface 4, and the second internal electrode 122 can be formed at a certain distance apart on the third surface 3. Also, the first and second internal electrodes 121 and 122 may be arranged separated from the fifth and sixth surfaces of the main body 110.

[0075] The conductive metal contained in the internal electrodes 121 and 122 may be one or more of Ni, Cu, Pd, Ag, Au, Pt, In, Sn, Al, Ti, and their alloys, but the present invention is not limited thereto.

[0076] The average thickness td of the dielectric layer 111 does not need to be particularly limited, and may be, for example, 0.1 μm to 10 μm. The average thickness te of the internal electrodes 121 and 122 does not need to be particularly limited, and may be, for example, 0.05 μm to 3.0 μm. Further, the average thickness td of the dielectric layer 111 and the average thickness te of the internal electrodes 121 and 122 can be arbitrarily set according to desired characteristics and applications. For example, in order to achieve miniaturization and high capacitance, in the case of small IT electronic components, the average thickness td of the dielectric layer 111 may be 0.4 μm or less, and the average thickness te of the internal electrodes 121 and 122 may be 0.4 μm or less.

[0077] The average thickness td of the dielectric layer 111 and the average thickness te of the internal electrodes 121 and 122 respectively mean the sizes of the dielectric layer 111 and the internal electrodes 121 and 122 in the first direction. The average thickness td of the dielectric layer 111 and the average thickness te of the internal electrodes 121 and 122 can be measured by scanning 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 thickness td of the dielectric layer 111 can be measured by measuring the thicknesses at a number of points of one dielectric layer 111, for example, 30 points equally spaced in the second direction, and then measuring the average value. Also, the average thickness te of the internal electrodes 121 and 122 can be measured by measuring the thicknesses at a number of points of one internal electrode 121 or 122, for example, 30 points equally spaced in the second direction, and then measuring the average value. The 30 equally spaced points can be specified in the capacitance forming portion Ac. On the other hand, after such average value measurements are performed for 10 dielectric layers 111 and 10 internal electrodes 121 and 122 respectively, and then the average values are measured, the average thickness td of the dielectric layer 111 and the average thickness te of the internal electrodes 121 and 122 can be further generalized.

[0078] The external electrodes 131 and 132 can be disposed on the third surface 3 and the fourth surface 4 of the main body 110.

[0079] The external electrodes 131 and 132 can include first and second external electrodes 131 and 132 respectively disposed on the third and fourth surfaces 3 and 4 of the main body 110 and connected to the first and second internal electrodes 121 and 122 respectively.

[0080] In this embodiment, the ceramic electronic component 100 having two external electrodes 131 and 132 is described. However, the number, shape, etc. of the external electrodes 131 and 132 can be changed according to the form of the internal electrodes 121 and 122 and other purposes.

[0081] On the other hand, the external electrodes 131 and 132 may be formed of any material as long as it has electrical conductivity, such as metal. A specific material may be determined in consideration of electrical characteristics, structural stability, etc., and it may further have a multilayer structure.

[0082] For example, the external electrodes 131 and 132 can 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.

[0083] To give a more specific example 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-based electrodes including a conductive metal and resin.

[0084] Also, the electrode layers 131a and 132a may be in a form in which a fired electrode and a resin-based electrode are sequentially formed on the main body. Also, the electrode layers 131a and 132a 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.

[0085] As the conductive metal contained in the electrode layers 131a and 132a, a material with excellent electrical conductivity can be used, but it is not particularly limited. For example, the conductive metal may be one or more of nickel (Ni), copper (Cu), and their alloys.

[0086] The plating layers 131b and 132b play a role in improving the mounting characteristics. The types of the plating layers 131b and 132b are not particularly limited, and they may be plating layers containing one or more of Ni, Sn, Pd, and their alloys, or may be formed of multiple layers.

[0087] More specific examples of the plating layers 131b and 132b are as follows. The plating layers 131b and 132b may be Ni plating layers or Sn plating layers, or may be in a form where a Ni plating layer and a Sn plating layer are sequentially formed on the electrode layers 131a and 132a, or may be in a form where a Sn plating layer, a Ni plating layer, and a Sn plating layer are sequentially formed. Also, the plating layers 131b and 132b may include a plurality of Ni plating layers and / or a plurality of Sn plating layers.

[0088] The size of the ceramic electronic component 100 does not need to be particularly limited.

[0089] However, in order to simultaneously achieve miniaturization and high capacitance, the thicknesses of the dielectric layer and the internal electrodes need to be reduced and the number of stacked layers needs to be increased. Therefore, in the ceramic electronic component 100 having a size of 1005 (length × width, 1.0 mm × 0.5 mm) or less, the effects of improving the reliability and insulation resistance according to the present invention can be more remarkable.

[0090] Therefore, considering manufacturing errors, the size of the external electrodes, etc., when the length of the ceramic electronic component 100 is 1.1 mm or less and the width is 0.55 mm or less, the effect of improving the reliability according to the present invention can be more remarkable. Here, the length of the ceramic electronic component 100 can mean the size in the second direction of the ceramic electronic component 100, and the width of the ceramic electronic component 100 can mean the size in the third direction of the ceramic electronic component 100.

[0091] (Experimental Example) A ceramic green sheet containing barium titanate (BaTiO3) as a main component and containing yttrium oxide (Y2O3), dysprosium oxide (Dy2O3), silicon oxide (SiO2), vanadium oxide (V2O5), and magnesium oxide (MgO) as sub-components was prepared. Here, the sub-components were added so as to satisfy the content of each element in Table 1 below, and the content of each element in Table 1 below means the number of moles of the element relative to 100 moles of Ti.

[0092] An internal electrode paste was printed on the above ceramic green sheet, and the ceramic green sheet was laminated and pressure-bonded to produce a laminate. Then, the above laminate was cut into unit chip sizes to produce green chips, and after being pre-fired at 400 °C for 12 hours in an air atmosphere, a second pre-firing was performed at 850 °C for 4 hours in an inert gas atmosphere. Then, after sintering at 1200 °C for 2 hours in a predetermined reducing atmosphere, an oxidation treatment was performed in an O2 atmosphere to produce a main body. Then, after applying a Cu paste to the main body, heat treatment was performed at 700 °C to form an external electrode and produce a sample chip.

[0093] BSi, GSi, and Tgb were measured by performing a line profile using a transmission electron microscope on the cross-sections in the first and second directions cut at the center in the third direction of the main body.

[0094] In the case of Comparative Example 1, MRe / Msi and BSi / GSi did not satisfy the conditions of the present invention, and the result of HALT was poor.

[0095] [Table 1]

[0096] In the case of Comparative Example 1, MRe / Msi and BSi / GSi did not satisfy the conditions of the present invention, and the result of HALT was poor.

[0097] In the cases of Comparative Examples 2 and 3, BSi / GSi satisfied the conditions of the present invention, but MRe / Msi did not satisfy the conditions of the present invention, and the HALT results were poor.

[0098] In the case of Comparative Example 4, MRe / Msi satisfied the conditions of the present invention, but BSi / GSi did not satisfy the conditions of the present invention, and the HALT results were poor.

[0099] On the other hand, in the cases of Invention Examples 1 to 3, it can be confirmed that 1.6 ≦ MRe / MSi ≦ 4.0 is satisfied, 2.0 ≦ BSi / GSi is satisfied, and the HALT results are excellent.

[0100] Also, in the cases of Invention Examples 1 to 3, the thickness of the grain boundaries could be ensured to be thicker than that in Comparative Examples 1 to 4.

[0101] As described above, the embodiments of the present invention have been described in detail. However, the present invention is not limited by the above-described embodiments and the accompanying drawings, but is limited by the appended claims. Therefore, various forms of substitution, modification, and change can be made by those having ordinary knowledge in the technical field without departing from the technical idea of the present invention described in the claims, and it can be said that these also belong to the scope of the present invention.

[0102] In addition, the expression "one embodiment" used in the present invention does not mean the same embodiment, but is provided to emphasize and explain each different unique feature. However, the above-presented one embodiment does not exclude being implemented in combination with the features of other one embodiments. For example, even if the matter described in a specific one embodiment is not described in another one embodiment, it can be understood as related to the description of the other one embodiment as long as there is no description contrary to or conflicting with that matter in the other one embodiment.

[0103] 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, singular expressions include plural expressions unless the context clearly indicates a different meaning.

Explanation of Signs

[0104] 100: Ceramic electronic component 110: Body 111: Dielectric layer 111a: Crystal grains 111b: Grain boundaries 112, 113: Cover parts 114, 115: Margin parts 121, 122: Internal electrodes 131, 132: External electrodes 131a, 132a: Electrode layers 131b, 132b: Plating layers

Claims

1. A body including a dielectric layer and internal electrodes alternately arranged with the dielectric layer, and an external electrode disposed on the body, wherein the dielectric layer includes a plurality of crystal grains and grain boundaries disposed between adjacent crystal grains, when the number of moles of a rare earth element with respect to 100 moles of Ti contained in the dielectric layer is MRe and the number of moles of Si is MSi, 1.6 ≦ MRe / MSi ≦ 4.0 is satisfied, and when the average Si content contained in the crystal grains is GSi and the maximum value of the Si content at the grain boundaries is BSi, 2.0 ≦ BSi / GSi is satisfied, a ceramic electronic component.

2. The ceramic electronic component according to claim 1, wherein MRe is 0.1 mole or more and 6.0 moles or less.

3. The ceramic electronic component according to claim 1, wherein MSi is 1.0 mole or more and 3.5 moles or less.

4. The ceramic electronic component according to claim 1, wherein GSi is 0.3 at% or more and 0.9 at% or less.

5. The ceramic electronic component according to claim 1, wherein BSi is 1.5 at% or more and 3.5 at% or less.

6. The ceramic electronic component according to claim 1, wherein the rare earth element includes one or more of Gd, La, Sm, Dy, Tb, Ho, Y, Yb, and Sc.

7. The ceramic electronic component according to claim 1, wherein the rare earth element includes Dy and Y.

8. The dielectric layer is BaTiO ３ , (Ba １－ｘ Ca ｘ )TiO ３ (0 < x < 1), Ba(Ti １－ｙ Ca ｙ )O ３ (0 < y < 1), (Ba １－ｘ Ca ｘ )(Ti １－ｙ Zr ｙ )O ３ (0 < x < 1, 0 < y < 1) and Ba(Ti １－ｙ Zr ｙ )O ３ (0 < y < 1), the ceramic electronic component according to claim 1, comprising one or more of them.

9. The dielectric layer further includes a first sub-component element, and the first sub-component element is one or more of V, Zr, Mn, Cr, Ti, Ni, Co, and W, the ceramic electronic component according to claim 1.

10. The ceramic electronic component according to claim 9, wherein the dielectric layer includes the first sub-component element in an amount of 0.5 mole or more and 3.0 moles or less with respect to 100 moles of Ti.

11. The dielectric layer further includes a second sub-component element, and the second sub-component element is Mg, the ceramic electronic component according to claim 1.

12. The ceramic electronic component according to claim 11, wherein the dielectric layer includes the second sub-component element in an amount of 0.1 mole or more and 3.0 moles or less with respect to 100 moles of Ti.

13. The ceramic electronic component according to claim 1, wherein when the average thickness of the grain boundaries is Tgb, Tgb is 8.0 nm or more.

14. The ceramic electronic component according to claim 13, wherein 8.0 nm ≦ Tgb ≦ 15.0 nm is satisfied.

15. The BSi and GSi in the ceramic electronic component according to claim 1 satisfy 2.0 ≤ BSi / GSi ≤ 5.0.

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