Multilayer capacitor and board on which multilayer capacitor is mounted

Abstract

The present disclosure provides a multilayer capacitor and a board on which the multilayer capacitor is mounted. The multilayer capacitor includes a capacitor body including stacked first and second dielectric layers and internal electrodes, and first and second external electrodes. The internal electrodes include first and second internal electrodes, a first floating electrode disposed on the first dielectric layer between the first and second internal electrodes, and second and third floating electrodes disposed on the second dielectric layer. The second floating electrode overlaps a portion of the first internal electrode and a portion of the first floating electrode, and the third floating electrode overlaps a portion of the second internal electrode and a portion of the first floating electrode. A / L is greater than or equal to 0.113, where L is a length of the capacitor body and a is a distance between the first floating electrode and the first or second internal electrode.

Description

[0001] This application claims the benefit of priority to Korean Patent Application No. 10-2020-0175198, filed on December 15, 2020, with the Korean Intellectual Property Office, and Korean Patent Application No. 10-2021-0171498, filed on December 3, 2021, with the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference for all purposes. Technical Field

[0002] This disclosure relates to a multilayer capacitor and a plate on which the multilayer capacitor is mounted. Background Technology

[0003] In recent years, with the rapid increase in the popularity of environmentally friendly and electric vehicles, the importance of the power drive system inside the vehicle has increased. As a result, the demand for multilayer capacitors required for the power drive system of electric devices has also increased.

[0004] For this type of multilayer capacitor used in the electric field, high capacitance can be achieved, excellent resistance to vibration and deformation is required, and it is designed to be used at high voltage.

[0005] One method for increasing the withstand voltage of multilayer capacitors is to use floating electrodes to divide the voltage.

[0006] However, in this case, there may be a problem of reliability degradation of the multilayer capacitor. Summary of the Invention

[0007] This summary is provided to introduce selected concepts in a simplified form, and these concepts are further described in the following detailed description. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used to help determine the scope of the claimed subject matter.

[0008] An exemplary embodiment provides a multilayer capacitor and a plate on which the multilayer capacitor is mounted, wherein a certain level of reliability can be ensured by using floating electrodes, while increasing withstand voltage characteristics.

[0009] According to an exemplary embodiment, a multilayer capacitor includes: a capacitor body having a first surface and a second surface opposite to each other, a third surface and a fourth surface connected to the first surface and the second surface and opposite to each other, and a fifth surface and a sixth surface connected to the first surface and the second surface, connected to the third surface and the fourth surface and opposite to each other; the capacitor body includes a plurality of stacked first dielectric layers, a plurality of second dielectric layers, and a plurality of internal electrodes; and a first external electrode and a second external electrode, respectively disposed on the third surface and the fourth surface of the capacitor body. The internal electrodes include: a first internal electrode and a second internal electrode, disposed on the first dielectric layer and spaced apart from each other in a first direction, and respectively connected to the first external electrode and the second external electrode; a first floating electrode, disposed on the first dielectric layer and located between the first internal electrode and the second internal electrode; and a second floating electrode and a third floating electrode, disposed on the second dielectric layer and spaced apart from each other in the first direction. The second floating electrode overlaps a portion of the first internal electrode and a portion of the first floating electrode, and the third floating electrode overlaps a portion of the second internal electrode and a portion of the first floating electrode. a / L is greater than or equal to 0.113, where L is the length of the capacitor body in the first direction, and a is the distance between the first floating electrode and the first inner electrode or the distance between the first floating electrode and the second inner electrode.

[0010] b / L can be greater than or equal to 0.09, where b is the distance between the second floating electrode and the third surface of the capacitor body or the distance between the third floating electrode and the fourth surface of the capacitor body.

[0011] c / W can be greater than or equal to 0.138, where W is the length of the capacitor body in the second direction, and c is the distance in the second direction between one of the first inner electrode, the second inner electrode, and the first floating electrode and the fifth or sixth surface of the capacitor body.

[0012] The first external electrode may include a first connecting portion and a first strip portion, and the second external electrode may include a second connecting portion and a second strip portion. The first connecting portion and the second connecting portion are respectively disposed on the third surface and the fourth surface of the capacitor body, and are respectively connected to the first internal electrode and the second internal electrode. The first strip portion and the second strip portion extend from the first connecting portion and the second connecting portion to a portion of the first surface of the capacitor body.

[0013] The first floating electrode to the third floating electrode may be spaced apart from the third surface to the sixth surface, the first outer electrode may be connected to the first inner electrode, and the second outer electrode may be connected to the second inner electrode.

[0014] In the stacking direction of the plurality of first dielectric layers and the plurality of second dielectric layers, the second floating electrode may partially overlap with the first inner electrode and partially overlap with the first floating electrode, and the third floating electrode may partially overlap with the second inner electrode and partially overlap with the first floating electrode.

[0015] According to an exemplary embodiment, a board on which a multilayer capacitor is mounted includes: a substrate having a first electrode pad and a second electrode pad on one surface; and the multilayer capacitor, wherein the multilayer capacitor is mounted such that the first external electrode and the second external electrode of the multilayer capacitor are respectively connected to the first electrode pad and the second electrode pad.

[0016] According to an exemplary embodiment, a multilayer capacitor includes: a capacitor body having a first surface and a second surface opposite to each other, a third surface and a fourth surface connected to the first surface and the second surface and opposite to each other in a first direction, and a fifth surface and a sixth surface connected to the first surface and the second surface, connected to the third surface and the fourth surface and opposite to each other in a second direction. The capacitor body includes a plurality of stacked first dielectric layers, a plurality of second dielectric layers, and a plurality of internal electrodes; and a first external electrode and a second external electrode, respectively disposed on the third surface and the fourth surface of the capacitor body. The plurality of internal electrodes include: a first internal electrode and a second internal electrode, disposed on the first dielectric layer and spaced apart from each other in the first direction, and respectively connected to the first external electrode and the second external electrode; a first floating electrode, disposed on the first dielectric layer and located between the first internal electrode and the second internal electrode; and a second floating electrode and a third floating electrode, disposed on the second dielectric layer and spaced apart from each other in the first direction. The second floating electrode overlaps a portion of the first internal electrode and a portion of the first floating electrode, and the third floating electrode overlaps a portion of the second internal electrode and a portion of the first floating electrode. b / L is greater than or equal to 0.09, where L is the length of the capacitor body in the first direction, and b is the distance between the second floating electrode and the third surface of the capacitor body or the distance between the third floating electrode and the fourth surface of the capacitor body.

[0017] According to an exemplary embodiment, a multilayer capacitor includes: a capacitor body having a first surface and a second surface opposite to each other, a third surface and a fourth surface connected to the first surface and the second surface and opposite to each other in a first direction, and a fifth surface and a sixth surface connected to the first surface and the second surface, connected to the third surface and the fourth surface and opposite to each other in a second direction. The capacitor body includes a plurality of stacked first dielectric layers, a plurality of second dielectric layers, and a plurality of internal electrodes; and a first external electrode and a second external electrode, respectively disposed on the third surface and the fourth surface of the capacitor body. The plurality of internal electrodes includes: a first internal electrode and a second internal electrode, respectively disposed on the first dielectric layer and spaced apart from each other in the first direction, and respectively connected to the first external electrode and the second external electrode; a first floating electrode, disposed on the first dielectric layer and located between the first internal electrode and the second internal electrode; and a second floating electrode and a third floating electrode, disposed on the second dielectric layer and spaced apart from each other in the first direction. The second floating electrode overlaps a portion of the first internal electrode and a portion of the first floating electrode, and the third floating electrode overlaps a portion of the second internal electrode and a portion of the first floating electrode. c / W is greater than or equal to 0.138, where W is the length of the capacitor body in the second direction, and c is the distance in the second direction between one of the first inner electrode, the second inner electrode, and the first floating electrode and the fifth or sixth surface of the capacitor body. Attached Figure Description

[0018] The above and other aspects, features, and advantages of the present invention will be more clearly understood by taking into account the accompanying drawings and the following detailed description, in which:

[0019] Figure 1 This is a schematic perspective view of a multilayer capacitor according to an embodiment;

[0020] Figure 2A and Figure 2B This shows the application to Figure 1 A plan view of the arrangement structure of the first inner electrode, the second inner electrode, and the first floating electrode to the third floating electrode;

[0021] Figure 3 It is along Figure 1 A cross-sectional view taken from line I-I';

[0022] Figure 4 It is along Figure 1 A cross-sectional view taken from line II-II';

[0023] Figure 5This is a graph showing the mean time to failure (MTTF) of a multilayer capacitor with an internal electrode and a floating electrode according to an embodiment. The MTTF varies according to the ratio (a / L) of the distance a between the first floating electrode and the first or second internal electrode in the multilayer capacitor to the length (L) of the capacitor body.

[0024] Figure 6 It is shown Figure 5 A graph of the average MTTF for each sample in the sample;

[0025] Figure 7 This is a graph showing the MTTF of a multilayer capacitor with an internal electrode and a floating electrode according to an embodiment. The MTTF varies according to the ratio (b / L) of the distance b between the first or second floating electrode in the multilayer capacitor and a surface of the capacitor body in the length direction to the length (L) of the capacitor body.

[0026] Figure 8 It is shown Figure 7 A graph of the average MTTF for each sample in the sample;

[0027] Figure 9 This is a graph showing the MTTF of a multilayer capacitor with an internal electrode and a floating electrode according to an embodiment. The MTTF varies according to the ratio (c / W) of the distance c between the first or second floating electrode in the multilayer capacitor and a surface of the capacitor body in the width direction to the width (W) of the capacitor body.

[0028] Figure 10 It is shown Figure 9 A graph of the average MTTF for each sample in the graph; and

[0029] Figure 11 This is a perspective view schematically illustrating the combined structure of a multilayer capacitor and a substrate according to an embodiment. Detailed Implementation

[0030] The following detailed embodiments are provided to aid the reader in gaining a comprehensive understanding of the methods, apparatus, and / or systems described herein. However, various changes, modifications, and equivalents of the methods, apparatus, and / or systems described herein will be readily understood by those skilled in the art. The order of operations described herein is merely illustrative and is not limited to the order presented; changes that will be readily understood by those skilled in the art may be made, except for operations that must occur in a specific order. Furthermore, for clarity and brevity, descriptions of functions and constructions well-known to those skilled in the art may be omitted.

[0031] The features described herein may be implemented in different forms and are not to be construed as being limited to the examples described herein. Rather, the examples described herein have been provided so that this disclosure will be thorough and complete and will fully convey the scope of this disclosure to those skilled in the art.

[0032] It should be noted here that the use of the term “may” in relation to examples or embodiments (e.g., what an embodiment or example may include or implement) means that there exists at least one embodiment or example that includes or implements such a feature, and is not limited to all embodiments or examples including or implementing such a feature.

[0033] Throughout the specification, when an element such as a layer, region, or substrate is described as being "on" another element, "connected to" another element, or "bonded to" another element, that element may be directly "on" another element, directly "connected to" another element, or directly "bonded to" another element, or there may be one or more other elements in between. In contrast, when an element is described as being "directly on" another element, "directly connected to" another element, or "directly bonded to" another element, there are no other elements in between.

[0034] As used herein, the term “and / or” includes any one or any combination of two or more of the relevant listed items.

[0035] Although terms such as “first,” “second,” and “third” may be used herein to describe various components, assemblies, regions, layers, or parts, these components, assemblies, regions, layers, or parts will not be limited by these terms. Rather, these terms are used only to distinguish one component, assembly, region, layer, or part from another. Therefore, without departing from the teaching of the examples described herein, the first component, first assembly, first region, first layer, or first part referred to as the first component, first assembly, first region, first layer, or first part may also be referred to as the second component, second assembly, second region, second layer, or second part.

[0036] For ease of description, spatial relative terms such as “above,” “above,” “below,” and “under” are used herein to describe the relationship between one element and another, as shown in the accompanying drawings. Such spatial relative terms are intended to include not only the orientation depicted in the drawings but also the different orientations of the device during use or operation. For example, if the device in the drawings is flipped, an element described as “above” or “above” relative to another element will then be “below” or “under” relative to said other element. Thus, the term “above” includes both above and below orientations depending on the spatial orientation of the device. The device may also be positioned in other ways (e.g., rotated 90 degrees or in other orientations), and the spatial relative terms used herein will be interpreted accordingly.

[0037] The terminology used herein is for the purpose of describing various examples only and is not intended to limit this disclosure. Unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. The terms “comprising,” “including,” and “having” enumerate the presence of the stated features, quantities, operations, components, elements, and / or combinations thereof, but do not exclude the presence or addition of one or more other features, quantities, operations, components, elements, and / or combinations thereof.

[0038] The shapes shown in the accompanying drawings may vary due to manufacturing techniques and / or tolerances. Therefore, the examples described herein are not limited to the specific shapes shown in the drawings, but include changes in shape that occur during manufacturing.

[0039] The features of the examples described herein can be combined in a variety of ways that will be readily understood after an understanding of the disclosure of this application. Furthermore, while the examples described herein have multiple constructions, other constructions that will be readily understood after an understanding of the disclosure of this application are possible.

[0040] The accompanying drawings may not be drawn to scale, and for clarity, illustration and convenience, the relative sizes, scales and depictions of the elements in the drawings may be exaggerated.

[0041] In addition, the same reference numerals will be used to describe the components shown in the accompanying drawings of the embodiments that have the same function within the same spirit.

[0042] When the direction is specified in this disclosure, Figure 1 In this context, X represents the length direction, Y represents the width direction, and Z represents the thickness direction. Additionally, in the following description, the X direction may also be described as a first direction, and the Y direction may also be described as a second direction.

[0043] Figure 1 This is a schematic perspective view of a multilayer capacitor according to an embodiment. Figure 2A and Figure 2B This shows the application to Figure 1 A plan view of the arrangement structure of the first inner electrode, the second inner electrode, and the first floating electrode to the third floating electrode. Figure 3 It is along Figure 1 A cross-sectional view taken from line I-I'. Figure 4 It is along Figure 1 The cross-sectional view taken from line II-II'.

[0044] Reference Figures 1 to 4 According to an embodiment, the multilayer capacitor 100 includes: a capacitor body 110, including a plurality of dielectric layers 111 and a plurality of inner electrodes; and a first outer electrode 130 and a second outer electrode 140.

[0045] In this case, the internal electrodes include a first internal electrode 121, a second internal electrode 122, a first floating electrode 123, a second floating electrode 124, and a third floating electrode 125.

[0046] The capacitor body 110 is formed by sintering multiple first dielectric layers 111 and multiple second dielectric layers 112 alternately stacked in the Z direction, and adjacent first dielectric layers 111 and second dielectric layers 112 can be integrated, such that the boundaries between them may not be visible without a scanning electron microscope (SEM). In this case, the capacitor body 110 may have a generally hexahedral shape. The capacitor body 110 may include a first surface 1 and a second surface 2 opposite in the third direction (Z direction), a third surface 3 and a fourth surface 4 connected to the first surface 1 and the second surface 2 and opposite in the first direction (X direction), and a fifth surface 5 and a sixth surface 6 connected to the first surface 1 to the fourth surface 4 and opposite in the second direction (Y direction).

[0047] The first dielectric layer 111 and the second dielectric layer 112 may include ceramic materials with high dielectric constants, such as barium titanate (BaTiO3) based ceramic powder, but the materials of the first dielectric layer 111 and the second dielectric layer 112 are not limited to this, as long as sufficient capacitance can be obtained.

[0048] In addition, various ceramic additives, organic solvents, plasticizers, binders and dispersants can be added together with ceramic powder to the materials of the first dielectric layer 111 and the second dielectric layer 112.

[0049] In this case, the ceramic additive may be at least one of transition metal oxides, transition metal carbides, rare earth elements, magnesium (Mg), and aluminum (Al).

[0050] Reference Figure 3 and Figure 4 In the cross-section of the multilayer capacitor 100, the portion in which no internal electrode is formed can be defined as the margin portion.

[0051] In this case, the edge portions located in the upper and lower parts of the capacitor body 110 in the Z direction can be defined as the upper cover 113 and the lower cover 114.

[0052] The upper cover 113 and the lower cover 114 can be formed by sintering multiple ceramic sheets, similar to the first dielectric layer 111 or the second dielectric layer 112. Except that no internal electrode is formed, the structure of the upper cover 113 and the lower cover 114 can be similar to the structure of the first dielectric layer 111 or the second dielectric layer 112 located in the center of the capacitor body 110.

[0053] In this embodiment, the first inner electrode 121, the second inner electrode 122 and the first floating electrode 123 are disposed on a first dielectric layer 111, and the second floating electrode 124 and the third floating electrode 125 are disposed on a second dielectric layer 112.

[0054] The first internal electrode 121, the second internal electrode 122, the first floating electrode 123, the second floating electrode 124, and the third floating electrode 125 are formed using conductive metals, and at least one of, for example, silver (Ag), lead (Pb), platinum (Pt), nickel (Ni), copper (Cu), and alloys thereof can be used as the conductive metal, and this disclosure is not limited thereto.

[0055] The first inner electrode 121 and the second inner electrode 122 are electrodes to which voltages of different polarities are applied, and are formed on at least one surface of a ceramic sheet forming a first dielectric layer 111, spaced apart from each other in the X direction, and are respectively led out through a third surface 3 and a fourth surface 4 in the capacitor body 110, the third surface 3 and the fourth surface 4 being two surfaces of the capacitor body 110 in the length direction.

[0056] The first floating electrode 123 is disposed on the first dielectric layer 111 and spaced apart from the first inner electrode 121 and the second inner electrode 122 in the X direction, and is also spaced apart from the third surface 3 to the sixth surface 6 of the capacitor body 110.

[0057] The second floating electrode 124 and the third floating electrode 125 are disposed on the second dielectric layer 112, and are alternately disposed in the capacitor body 110 in the Z direction with the first inner electrode 121, the second inner electrode 122 and the first floating electrode 123, and are disposed on a single second dielectric layer 112 such that they are spaced apart from each other in the X direction.

[0058] In addition, the second floating electrode 124 and the third floating electrode 125 are also arranged to be spaced apart from the third surface 3 to the sixth surface 6 of the capacitor body.

[0059] In this case, one end of the second floating electrode 124 overlaps with a portion of the first inner electrode 121 in the Z direction, and the other end of the second floating electrode 124 overlaps with a portion of the first floating electrode 123 in the Z direction.

[0060] One end of the third floating electrode 125 overlaps with a portion of the second inner electrode 122 in the Z direction, and the other end of the third floating electrode 125 overlaps with a portion of the first floating electrode 123 in the Z direction.

[0061] On the other hand, the lengths of the first inner electrode 121, the second inner electrode 122, and the first floating electrode 123 in the Y direction may be greater than the lengths of the second floating electrode 124 and the third floating electrode 125 in the Y direction.

[0062] When a voltage is applied to the first and second external electrodes according to the structure of the internal electrodes, a multilayer capacitor can form a capacitance.

[0063] In addition, the multilayer capacitor 100 of this embodiment may include a first external electrode 130 and a second external electrode 140, which are respectively formed on the third surface 3 and the fourth surface 4 of the capacitor body 110 in the X direction, and respectively contact and are electrically connected to the first internal electrode 121 and the second internal electrode 122 exposed through the third surface 3 and the fourth surface 4 of the capacitor body 110 in the X direction.

[0064] The first external electrode 130 includes a first conductive layer 131 formed using a conductive metal, and the second external electrode 140 includes a second conductive layer 141 formed using a conductive metal. The first conductive layer 131 and the second conductive layer 141 may be formed using, for example, silver (Ag), lead (Pb), platinum (Pt), nickel (Ni), copper (Cu) and alloys thereof, and this disclosure is not limited thereto.

[0065] The first conductive layer 131 may include a first connecting portion 131a and a first strip portion 131b, and the second conductive layer 141 may include a second connecting portion 141a and a second strip portion 141b. The first connecting portion 131a and the second connecting portion 141a are respectively formed on the third surface 3 and the fourth surface 4 of the capacitor body 110 and are respectively connected to the first inner electrode 121 and the second inner electrode 122. The first strip portion 131b and the second strip portion 141b extend from the first connecting portion 131a and the second connecting portion 141a to a portion of the first surface 1 of the capacitor body 110.

[0066] In this case, the first strip portion 131b and the second strip portion 141b may further extend to a portion of the fifth surface 5, a portion of the sixth surface 6, and a portion of the second surface 2 of the capacitor body 110 to increase the adhesive strength.

[0067] Additionally, if necessary, a first plating layer 132 and a second plating layer 142 may be formed in the first external electrode 130 and the second external electrode 140 to cover the first conductive layer 131 and the second conductive layer 141, respectively.

[0068] The first plating layer 132 may include a first nickel (Ni) plating layer and a first tin (Sn) plating layer, and the second plating layer 142 may include a second nickel (Ni) plating layer and a second tin (Sn) plating layer. The first nickel (Ni) plating layer and the second nickel (Ni) plating layer are respectively formed on the first conductive layer 131 and the second conductive layer 141, and the first tin (Sn) plating layer and the second tin (Sn) plating layer are respectively formed on the first nickel plating layer and the second nickel plating layer.

[0069] When the multilayer capacitor 100 is mounted on a printed circuit board or the like using solder, a first plating layer 132 and a second plating layer 142 are provided to increase the strength of the mutual adhesion.

[0070] In addition, the first plating layer 132 may include a 1-1 connecting portion 132a and a 1-2 strip portion 132b, and the second plating layer 142 may include a 2-1 connecting portion 142a and a 2-2 strip portion 142b.

[0071] 1-1 Connection portion 132a is a portion formed on the first connection portion 131a of the first conductive layer 131, and 1-2 strip portion 132b is a portion extending from 1-1 connection portion 132a to a portion of the first surface 1 of the capacitor body 110.

[0072] In this case, the 1-2 strip portion 132b may cover the first strip portion 131b and may further extend to a portion of the fifth surface 5 of the capacitor body 110, a portion of the sixth surface 6 of the capacitor body 110, and a portion of the second surface 2 to increase adhesive strength, etc.

[0073] 2-1 Connecting portion 142a is a portion formed on the second connecting portion 141a of the second conductive layer 141, and 2-2 Strip portion 142b is a portion extending from the 2-1 connecting portion 142a to a portion of the first surface 1 of the capacitor body 110.

[0074] In this case, the 2-2 tape portion 142b covers the second tape portion 141b and may further extend to a portion of the fifth surface 5 of the capacitor body 110, a portion of the sixth surface 6 of the capacitor body 110, and a portion of the second surface of the capacitor body 110 to increase adhesive strength, etc.

[0075] According to this embodiment, since the internal electrodes are provided with a floating electrode structure, the multilayer capacitor can achieve high voltage and a certain level of reliability can be ensured by voltage division.

[0076] In a multilayer capacitor with a floating electrode structure, the reliability of the multilayer capacitor varies depending on the distance between the floating electrode and the first inner electrode or the second inner electrode (e.g., parameter a), the margin of the inner electrodes (e.g., parameter b or c), the distance between the floating electrodes, etc.

[0077] In this embodiment, the reliability of this high-voltage product can be further improved by adjusting the edge distance of the inner electrodes or the distance between the inner electrodes at an appropriate ratio.

[0078] The table below shows a comparison of the mean time to failure (MTTF) of multilayer capacitors, which varies depending on the size of the capacitor body, the spacing of the internal electrodes, the edge distance, etc.

[0079] MTTF is the mean time between failures obtained by measuring simple operation time or equipment usage time under conditions of 105°C and 1.5Vr.

[0080] [Table 1]

[0081]

[0082] In Table 1, the MTTF variation according to a / L is shown when the length of the capacitor body in the X direction is defined as L, the width of the capacitor body in the Y direction is defined as W, the distance between the first floating electrode and the first inner electrode or the distance between the first floating electrode and the second inner electrode is defined as a, the distance between the second floating electrode and the third surface of the capacitor body or the distance between the third floating electrode and the fourth surface of the capacitor body is defined as b, and the distance between one of the first inner electrode, the second inner electrode and the first floating electrode and the fifth or sixth surface of the capacitor body is defined as c.

[0083] In this case, the multilayer capacitor used in the test has an L of 2.22 mm, a W of 1.45 mm, a b of 0.25 mm, and a c of 0.25 mm.

[0084] In one example, the length L of the capacitor body in the X direction can refer to: the maximum length of a plurality of line segments parallel to the X direction connecting the outermost boundary lines of the capacitor body in an image of the capacitor body in the XZ plane at the central part of the capacitor in the Y direction obtained by optical microscopy or SEM, or alternatively, the average length of the plurality of line segments.

[0085] In one example, the width W of the capacitor body in the Y direction can refer to: the maximum length of a plurality of line segments parallel to the Y direction connecting the outermost boundary lines of the capacitor body in a cross-sectional image of the capacitor body at the central portion of the capacitor in the X direction, obtained by optical microscopy or SEM, or alternatively, the average length of the plurality of line segments. Alternatively, a micrometer or calipers can be used to measure the width W of the capacitor body in the Y direction.

[0086] In one example, measurements of parameters a, b, and c can be performed based on optical microscope or SEM images of the corresponding cross-sections described above. In one example, parameters a, b, or c may refer to the maximum value among multiple measurements of the corresponding parameter taken at different locations, or alternatively, the average of multiple measurements. Other cross-sections, other measurement methods, or other measurement tools, as understood by those skilled in the art, may be used even if not described in this disclosure.

[0087] Refer to Table 1 and Figure 5 and Figure 6 (exist Figure 5 In the figure, different symbols are used to represent different values ​​of a). It can be seen that MTTF has the minimum value in #2 with an a / L of 9.0%, and MTTF gradually increases from #3 with an a / L of 11.3%.

[0088] Therefore, when the length of the capacitor body in the X direction is defined as L, and the distance between the first floating electrode and the first inner electrode or the distance between the first floating electrode and the second inner electrode is defined as a, a / L can be 0.113 or greater.

[0089] [Table 2]

[0090]

[0091] Table 2 shows the variation of MTTF with respect to b / L when the distance between the second floating electrode and the third surface of the capacitor body or the distance between the third floating electrode and the fourth surface of the capacitor body is defined as b.

[0092] In this case, the dimensions of the multilayer capacitor used in the test are the same as in the previous test, with L being 2.22 mm and W being 1.45 mm. Furthermore, by applying #3 of Table 1 (the critical point in the previous test), a is set to 0.25 mm and c is set to 0.25 mm.

[0093] Refer to Table 2 and Figure 7 and Figure 8 (exist Figure 7 In the figure, different symbols are used to represent different b), and it can be seen that MTTF gradually increases from #7 when b / L is 9.0%.

[0094] Therefore, when the distance between the second floating electrode and the third surface of the capacitor body or the distance between the third floating electrode and the fourth surface of the capacitor body is defined as b, b / L can be 0.09 or greater.

[0095] [Table 3]

[0096]

[0097] Table 3 shows the variation of MTTF according to the change of c / W when the length of the capacitor body in the Y direction is defined as W, and the distance between one of the first inner electrode, the second inner electrode, and the first floating electrode and the fifth or sixth surface of the capacitor body is defined as c.

[0098] In this case, the dimensions of the multilayer capacitor used in the test are the same as in the previous test, with L being 2.22 mm and W being 1.45 mm. Furthermore, a is 0.25 mm and b is 0.25 mm.

[0099] Refer to Table 3 and Figure 9 and Figure 10 (exist Figure 9 In the figure, different symbols are used to represent different c), and it can be seen that MTTF increases significantly from c / W of 13.8% for #12.

[0100] Therefore, when the length of the capacitor body in the Y direction is defined as W and the distance between one of the first inner electrode, the second inner electrode, and the first floating electrode and the fifth or sixth surface of the capacitor body is defined as c, c / W can be 0.138 or greater.

[0101] Figure 11 This is a perspective view schematically illustrating the combined structure of a multilayer capacitor and a substrate according to an embodiment.

[0102] Reference Figure 11 According to this embodiment, a board on which a multilayer capacitor is mounted includes: a substrate 210, on which a multilayer capacitor 100 is mounted; and a first electrode pad 221 and a second electrode pad 222, which are spaced apart from each other on the upper surface of the substrate 210.

[0103] With the first external electrode 130 and the second external electrode 140 in contact with the first electrode pad 221 and the second electrode pad 222 respectively and located on the first electrode pad 221 and the second electrode pad 222, the multilayer capacitor 100 can be electrically connected to the substrate 210 through solder 231 and 232.

[0104] In this case, according to an exemplary embodiment, the multilayer capacitor 100 may be a multilayer ceramic capacitor, and a detailed description thereof will be omitted below to avoid redundancy.

[0105] As described above, according to an exemplary embodiment, it has the effect of preventing the reduction in reliability caused by the application of floating electrodes in multilayer capacitors.

[0106] While this disclosure includes specific examples, it will be readily understood by those skilled in the art that various changes in form and detail may be made to these examples without departing from the spirit and scope of the claims and their equivalents. The examples described herein are to be considered descriptive only and not for limiting purposes. The description of features or aspects in each example is to be considered applicable to similar features or aspects in other examples. Suitable results may be obtained if the described techniques are performed in a different order, and / or if components in the described system, architecture, apparatus, or circuit are combined in a different manner, and / or if components in the described system, architecture, apparatus, or circuit are replaced or added by other components or their equivalents. Therefore, the scope of this disclosure is not limited by the specific embodiments but by the claims and their equivalents, and all variations within the scope of the claims and their equivalents are to be construed as being included in this disclosure.

Claims

1. A multilayer capacitor, comprising: A capacitor body has a first surface and a second surface opposite to each other, a third surface and a fourth surface connected to the first surface and the second surface and opposite to each other in a first direction, and a fifth surface and a sixth surface connected to the first surface and the second surface, connected to the third surface and the fourth surface and opposite to each other in a second direction. The capacitor body includes a plurality of stacked first dielectric layers, a plurality of second dielectric layers and a plurality of internal electrodes. as well as The first external electrode and the second external electrode are respectively disposed on the third surface and the fourth surface of the capacitor body. The plurality of internal electrodes include: The first inner electrode and the second inner electrode are disposed on the first dielectric layer and spaced apart from each other in the first direction, and are respectively connected to the first outer electrode and the second outer electrode; A first floating electrode is disposed on the first dielectric layer and located between the first inner electrode and the second inner electrode; and The second floating electrode and the third floating electrode are disposed on the second dielectric layer and spaced apart from each other in the first direction. The second floating electrode overlaps with a portion of the first inner electrode and also with a portion of the first floating electrode. The third floating electrode overlaps with a portion of the second inner electrode and a portion of the first floating electrode, and a / L is greater than or equal to 0.113 and less than or equal to 0.135, where L is the length of the capacitor body in the first direction, and a is the distance between the first floating electrode and the first inner electrode or the distance between the first floating electrode and the second inner electrode.

2. The multilayer capacitor of claim 1, wherein, b / L is greater than or equal to 0.09, where b is the distance between the second floating electrode and the third surface of the capacitor body or the distance between the third floating electrode and the fourth surface of the capacitor body.

3. The multilayer capacitor according to claim 1, wherein, c / W is greater than or equal to 0.138, where W is the length of the capacitor body in the second direction, and c is the distance in the second direction between one of the first inner electrode, the second inner electrode, and the first floating electrode and the fifth or sixth surface of the capacitor body.

4. The multilayer capacitor according to claim 1, wherein, b / L is greater than or equal to 0.09, where b is the distance between the second floating electrode and the third surface of the capacitor body or the distance between the third floating electrode and the fourth surface of the capacitor body. c / W is greater than or equal to 0.138, where W is the length of the capacitor body in the second direction, and c is the distance in the second direction between one of the first inner electrode, the second inner electrode, and the first floating electrode and the fifth or sixth surface of the capacitor body.

5. The multilayer capacitor according to claim 1, wherein, The lengths of the first inner electrode, the second inner electrode, and the first floating electrode in the second direction are greater than the lengths of the second floating electrode and the third floating electrode in the second direction.

6. The multilayer capacitor according to claim 1, wherein, The first external electrode includes a first connecting portion and a first strip portion, and the second external electrode includes a second connecting portion and a second strip portion. The first connecting portion and the second connecting portion are respectively disposed on the third surface and the fourth surface of the capacitor body, and are respectively connected to the first internal electrode and the second internal electrode. The first strip and the second strip extend from the first connection portion and the second connection portion, respectively, to a portion of the first surface of the capacitor body.

7. The multilayer capacitor according to claim 1, wherein, The first floating electrode, the second floating electrode, and the third floating electrode are spaced apart from the third surface, the fourth surface, the fifth surface, and the sixth surface. The first external electrode is connected to the first internal electrode, and The second outer electrode is connected to the second inner electrode.

8. The multilayer capacitor according to claim 1, wherein, The first direction is perpendicular to the third and fourth surfaces of the capacitor body, and the second direction is perpendicular to the fifth and sixth surfaces of the capacitor body.

9. The multilayer capacitor according to claim 1, wherein, In the stacking direction of the plurality of first dielectric layers and the plurality of second dielectric layers, the second floating electrode partially overlaps with the first inner electrode and partially overlaps with the first floating electrode, and the third floating electrode partially overlaps with the second inner electrode and partially overlaps with the first floating electrode.

10. A plate on which a multilayer capacitor is mounted, the plate comprising: The substrate has a first electrode pad and a second electrode pad on its surface; as well as The multilayer capacitor according to any one of claims 1-9, in, The multilayer capacitor is mounted such that its first external electrode and second external electrode are respectively connected to the first electrode pad and the second electrode pad.

11. A multilayer capacitor, comprising: A capacitor body has a first surface and a second surface opposite to each other, a third surface and a fourth surface connected to the first surface and the second surface and opposite to each other in a first direction, and a fifth surface and a sixth surface connected to the first surface and the second surface, connected to the third surface and the fourth surface and opposite to each other in a second direction. The capacitor body includes a plurality of stacked first dielectric layers, a plurality of second dielectric layers and a plurality of internal electrodes. as well as The first external electrode and the second external electrode are respectively disposed on the third surface and the fourth surface of the capacitor body. The plurality of internal electrodes include: The first inner electrode and the second inner electrode are disposed on the first dielectric layer and spaced apart from each other in the first direction, and are respectively connected to the first outer electrode and the second outer electrode; A first floating electrode is disposed on the first dielectric layer and located between the first inner electrode and the second inner electrode; and The second floating electrode and the third floating electrode are disposed on the second dielectric layer and spaced apart from each other in the first direction. The second floating electrode overlaps with a portion of the first inner electrode and also with a portion of the first floating electrode. The third floating electrode overlaps with a portion of the second inner electrode and a portion of the first floating electrode, and b / L is greater than or equal to 0.135, where L is the length of the capacitor body in the first direction, and b is the distance between the second floating electrode and the third surface of the capacitor body or the distance between the third floating electrode and the fourth surface of the capacitor body.

12. The multilayer capacitor according to claim 11, wherein, c / W is greater than or equal to 0.138, where W is the length of the capacitor body in the second direction, and c is the distance in the second direction between one of the first inner electrode, the second inner electrode, and the first floating electrode and the fifth or sixth surface of the capacitor body.

13. The multilayer capacitor according to claim 11, wherein, The lengths of the first inner electrode, the second inner electrode, and the first floating electrode in the second direction are greater than the lengths of the second floating electrode and the third floating electrode in the second direction. Wherein, c / W is greater than or equal to 0.207, where W is the length of the capacitor body in the second direction, and c is the distance in the second direction between one of the first inner electrode, the second inner electrode, and the first floating electrode and the fifth or sixth surface of the capacitor body.

14. The multilayer capacitor according to claim 11, wherein, The first external electrode includes a first connecting portion and a first strip portion, and the second external electrode includes a second connecting portion and a second strip portion. The first connecting portion and the second connecting portion are respectively disposed on the third surface and the fourth surface of the capacitor body, and are respectively connected to the first internal electrode and the second internal electrode. The first strip and the second strip extend from the first connection portion and the second connection portion, respectively, to a portion of the first surface of the capacitor body.

15. The multilayer capacitor according to claim 11, wherein, The first floating electrode, the second floating electrode, and the third floating electrode are spaced apart from the third surface, the fourth surface, the fifth surface, and the sixth surface. The first external electrode is connected to the first internal electrode, and The second outer electrode is connected to the second inner electrode.

16. The multilayer capacitor according to claim 11, wherein, In the stacking direction of the plurality of first dielectric layers and the plurality of second dielectric layers, the second floating electrode partially overlaps with the first inner electrode and partially overlaps with the first floating electrode, and the third floating electrode partially overlaps with the second inner electrode and partially overlaps with the first floating electrode.

17. A multilayer capacitor, comprising: A capacitor body has a first surface and a second surface opposite to each other, a third surface and a fourth surface connected to the first surface and the second surface and opposite to each other in a first direction, and a fifth surface and a sixth surface connected to the first surface and the second surface, connected to the third surface and the fourth surface and opposite to each other in a second direction. The capacitor body includes a plurality of stacked first dielectric layers, a plurality of second dielectric layers and a plurality of internal electrodes. as well as The first external electrode and the second external electrode are respectively disposed on the third surface and the fourth surface of the capacitor body. The plurality of internal electrodes include: The first inner electrode and the second inner electrode are disposed on the first dielectric layer and spaced apart from each other in the first direction, and are respectively connected to the first outer electrode and the second outer electrode; A first floating electrode is disposed on the first dielectric layer and located between the first inner electrode and the second inner electrode; and The second floating electrode and the third floating electrode are disposed on the second dielectric layer and spaced apart from each other in the first direction. The second floating electrode overlaps with a portion of the first inner electrode and also with a portion of the first floating electrode. The third floating electrode overlaps with a portion of the second inner electrode and a portion of the first floating electrode, and c / W is greater than or equal to 0.138 and less than or equal to 0.172, where W is the length of the capacitor body in the second direction, and c is the distance in the second direction between one of the first inner electrode, the second inner electrode, and the first floating electrode and the fifth or sixth surface of the capacitor body.

18. The multilayer capacitor according to claim 17, wherein, The lengths of the first inner electrode, the second inner electrode, and the first floating electrode in the second direction are greater than the lengths of the second floating electrode and the third floating electrode in the second direction.

19. The multilayer capacitor according to claim 17, wherein, The first external electrode includes a first connecting portion and a first strip portion, and the second external electrode includes a second connecting portion and a second strip portion. The first connecting portion and the second connecting portion are respectively disposed on the third surface and the fourth surface of the capacitor body, and are respectively connected to the first internal electrode and the second internal electrode. The first strip and the second strip extend from the first connection portion and the second connection portion, respectively, to a portion of the first surface of the capacitor body.

20. The multilayer capacitor according to claim 17, wherein, The first floating electrode, the second floating electrode, and the third floating electrode are spaced apart from the third surface, the fourth surface, the fifth surface, and the sixth surface. The first external electrode is connected to the first internal electrode, and The second outer electrode is connected to the second inner electrode.

21. The multilayer capacitor according to claim 17, wherein, In the stacking direction of the plurality of first dielectric layers and the plurality of second dielectric layers, the second floating electrode partially overlaps with the first inner electrode and partially overlaps with the first floating electrode, and the third floating electrode partially overlaps with the second inner electrode and partially overlaps with the first floating electrode.

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