Ceramic electronic component, ceramic electronic component manufacturing method, and ceramic electronic component-mounting circuit board

Disclosed is a ceramic electronic component having external electrodes on each of opposed end portions of a rectangular parallelepiped component body. A first direction dimension, a second direction dimension and a third direction dimension of the component body satisfy a condition of second direction dimension>first direction dimension>third direction dimension. The external electrodes are of a five-face type having a first face portion, a second face portion, a third face portion, a fourth face portion and a fifth face portion. At least one edge of the fourth face portion and the fifth face portion of the external electrode has a recess portion recessed from the edge toward the first face portion. Both side portions in the third direction of the recess portion are covering portions which cover ridge portions of the two faces in the second direction of the component body.

CROSS REFERENCE TO RELATED APPLICATION

This application is based upon and claims benefit of priority from Japanese Patent Application No. 2018-193502, filed on Oct. 12, 2018, the entire contents of which are incorporated herein by reference.

BACKGROUND

The present disclosure relates to a ceramic electronic component such as a multilayer ceramic capacitor, a manufacturing method for the ceramic electronic component, and a ceramic electronic component-mounting circuit board in which the ceramic electronic component is mounted on a circuit board.

Generally, a ceramic electronic component such as a multilayer ceramic capacitor has external electrodes on each of lengthwise end portions of a rectangular parallelepiped component body satisfying a condition of length direction dimension>width direction dimension, but recently, a so-called LW-reversed type ceramic electronic component is also known, in which a dimensional relationship between the length direction dimension and the width direction dimension is reversed (seeFIG. 4in Japanese Patent Laid-Open No. 2014-146669).

On the other hand, with thinning of electronic apparatuses such as smartphones and notebook computers, ceramic electronic components mounted on circuit boards are required to correspond to low-height mounting (low mounting height). That is, it is necessary to reduce a height direction dimension of a component body for satisfying the above requirements in the LW-reversed type ceramic electronic component.

Incidentally, since the LW-reversed type ceramic electronic component has external electrodes on each of lengthwise end portions of a rectangular parallelepiped component body satisfying a condition of width direction dimension>length direction dimension, a bending strength according to a direction intersecting with the length direction is generally higher than that of a general type ceramic electronic component having the same external dimensions of the component body, in a case of a five-face type external electrode (so-called four-cornered cap shape, having a first face portion formed on one face in a length direction of the component body, a second face portion and a third face portion formed on a part of two faces in a height direction of the component body, and a fourth face portion and a fifth face portion formed on a part of two faces in a width direction of the component body: seeFIG. 4in Japanese Patent Laid-Open No. 2014-146669).

However, even in the case of the LW-reversed type ceramic electronic component (the external electrode is of the aforementioned five-face type), when the height direction dimension of the component body is reduced, e.g., to 150 μm or smaller for satisfying the aforementioned requirements, cracks extends in the height direction especially on the two faces in the width direction of the component body, i.e., a so-called crack extension phenomenon is easily caused due to application of an external force that bends the ceramic electronic component in a direction intersecting with the length direction. As a result, there is a growing concern that the ceramic electronic component has dysfunction.

SUMMARY

It is desirable to provide a ceramic electronic component, a ceramic electronic component manufacturing method, and a ceramic electronic component-mounting circuit board, which can suppress a crack extension phenomenon causable in the component body even in a case where the height direction dimension of the LW-reversed type component body is reduced.

According to an embodiment of the present disclosure, there is provided a ceramic electronic component having external electrodes on each of opposed end portions of a rectangular parallelepiped component body, in which under a condition that a facing direction of opposed two faces of the component body is defined as a first direction, a facing direction of other opposed two faces is defined as a second direction, and a facing direction of the remaining opposed two faces is defined as a third direction, and dimensions along the respective directions are defined as a first direction dimension, a second direction dimension and a third direction dimension, respectively, the first direction dimension, the second direction dimension and the third direction dimension of the component body satisfy a condition of second direction dimension>first direction dimension>third direction dimension,

the external electrodes are of a five-face type having a first face portion formed on one face in the first direction of the component body, a second face portion and a third face portion formed on a part of two faces in the third direction of the component body, and a fourth face portion and a fifth face portion formed on a part of two faces in the second direction of the component body,

at least one edge of the fourth face portion and the fifth face portion of the external electrode has a recess portion recessed from the edge toward the first face portion, and both side portions in the third direction of the recess portion are covering portions which cover ridge portions of the two faces in the second direction of the component body.

The ceramic electronic component manufacturing method according to the present disclosure is a method for manufacturing the aforementioned ceramic electronic component, in which a process for producing the external electrode includes: forming, on a surface of the component body, a base conductor layer corresponding to the first face portion, the second face portion and the third face portion, and a fourth face portion and a fifth face portion having the recess portions and the covering portions; and forming, on the surface of the base conductor layer, at least one covering conductor layer.

Furthermore, in the ceramic electronic component-mounting circuit board according to the present disclosure, the aforementioned ceramic electronic component is mounted on the circuit board.

The ceramic electronic component, the ceramic electronic component-manufacturing method, and the ceramic electronic component-mounting circuit board according to the present disclosure can suppress the crack extension phenomenon causable in the component body even in a case where the ceramic electronic component is of a LW-reversed type and the height direction dimension of the component body is reduced.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

For convenience sake, in the following explanation, a facing direction of opposed two faces of a component body11depicted inFIGS. 1A, 1B, 1C and 1D(lateral direction inFIG. 1A,FIG. 1BandFIG. 1C) is denoted as “first direction d1,” a facing direction of other opposed two faces (vertical direction inFIG. 1AandFIG. 1B, and lateral direction inFIG. 1D) is denoted as “second direction d2,” a facing direction of the remaining opposed two faces (vertical direction inFIG. 1CandFIG. 1D) is denoted as “third direction d3.”

In addition, a dimension along the first direction dl of each constituent is denoted as “first direction dimension D1[symbol of constituent],” a dimension along the second direction d2is denoted as “second direction dimension D2[symbol of constituent],” and a dimension along the third direction d3is denoted as “third direction dimension D3[symbol of constituent].” Note that, when explaining internal electrode layers11a,dielectric layers11b,dielectric margin portions11cand11d,external electrodes12, and the like, a term “thickness” is optionally used for promoting understanding. Incidentally, a numerical value cited as each dimension refers to a design basic dimension and does not include a manufacture dimensional tolerance.

FIGS. 1A, 1B, 1C, 1D, 2A, 2B, 3A, 3B, 4A, 4B, 5 and 6relate to a ceramic electronic component10in which the present disclosure is applied to the multilayer ceramic capacitor. The ceramic electronic component10depicted inFIGS. 1A, 1B, 1C, 1D, 2A, 2B, 3A, 3B, 4A, 4B, 5 and 6falls under the LW-reversed type described in BACKGROUND, also corresponds to low-height mounting (low mounting height), and has the external electrodes12on each end portion in the first direction dl of the rectangular parallelepiped component body11.

A first direction dimension D1[11], a second direction dimension D2[11] and a third direction dimension D3[11] of the component body11satisfy a condition of second direction dimension D2[11]>first direction dimension D1[11]>third direction dimension D3[11]. Incidentally, each corner portion (symbol is omitted) and each ridge portion RP of the component body11are somewhat rounded.

In addition, the component body11incorporates a capacitive portion (symbol is omitted) as a functional portion in which a plurality of rectangular internal electrode layers11aare laminated in the third direction d3through the dielectric layers11b.As depicted inFIG. 2AandFIG. 2B, this capacitive portion is surrounded by the dielectric margin portions11con the both sides in the third direction d3and dielectric margin portions11don the both sides in the second direction d2.

Furthermore, as depicted inFIG. 2A, the plurality of internal electrode layers11aare alternately shifted in the first direction d1, and one edge in the first direction d1of the internal electrode layer11aodd-numbered from the top inFIG. 2Ais connected to a first face portion12aof one external electrode12, and the other edge in the first direction d1of the internal electrode layer11aeven-numbered from the top inFIG. 2Ais connected to the first face portion12aof the other external electrode12.

The third direction dimension D3[11] of the component body11can be, e.g., within a range of 60 to 120 μm, or 25 to 60 μm in consideration of low-height mounting (low mounting height) of the ceramic electronic component10. The first direction dimension D1[11] and the second direction dimension D2[11] of the component body11are not particularly limited in light of the relationship with low-height mounting (low mounting height) of the ceramic electronic component10. However, in light of a balance with the third direction dimension D3[11], the first direction dimension D1[11] can be, e.g., within a range of 200 to 800 μm, and the second direction dimension D2[11] can be, e.g., within a range of 400 to 1600 μm.

Thicknesses of the internal electrode layer11a and the dielectric layer11bcan be, e.g., within a range of 0.3 to 4 μm in consideration of low-height mounting (low mounting height) of the ceramic electronic component10. Thicknesses of the dielectric margin portions11cand11dcan be, e.g., within a range of 3 to 30 μm in consideration of low-height mounting (low mounting height) of the ceramic electronic component10.

Incidentally, a first direction dimension D1[11a] and a second direction dimension D2[11a] of the internal electrode layer11a,and the total number of the internal electrode layers11acan be arbitrarily changed depending on external dimensions, a desired capacitance value, and the like of the ceramic component body11. The desired capacitance value of the ceramic electronic component10corresponding to low-height mounting (low mounting height) can be, e.g., within a range of 0.1 to 0.3 μF, or 0.3 to 1.0 μF.

Examples of main ingredients of the dielectric layer11band the dielectric margin portions11cand11dinclude dielectric ceramics such as barium titanate, strontium titanate, calcium titanate, magnesium titanate, calcium zirconate, calcium titanate zirconate, barium zirconate, and titanium oxide. Examples of the main ingredient of the internal electrode layer11ainclude metals such as nickel, copper, palladium, platinum, silver, gold, and an alloy thereof.

Incidentally, the main ingredient of the dielectric layer11band the main ingredient of the dielectric margin portion11cmay be different from each other, or otherwise the main ingredient of the dielectric layer11b,the main ingredient of the dielectric margin portion11con one side in the third direction d3, and the main ingredient of the dielectric margin portion11con the other side in the third direction d3may be different from each other.

On the other hand, the external electrode12is of a five-face type having the first face portion12aformed on one face in the first direction dl of the component body11, a second face portion12band a third face portion12cformed on a part of two faces in the third direction d3of the component body11, and a fourth face portion12dand a fifth face portion12eformed on a part of two faces in the second direction d2of the component body11. That means, in the ceramic electronic component10, any face in the third direction d3can be used as a mounting face (connection face). Incidentally, in a view of the second face portion12band the third face portion12cfrom the third direction d3, the two corner portions (symbol is omitted) on the side of the first face portion12aare slightly rounded (e.g., a curvature radius is within a range of 10 to 150 μm), or otherwise tapered commensurately with the roundness.

As will be explained later with reference toFIGS. 8A, 8B and 8C, the roundness of the two corner portions on the edge sides of the second face portion12band the third face portion12ccan be formed larger than the roundness of the two corner portions on the side of the first face portion12a.

Maximum values of a first direction dimension D1[12b] of the second face portion12b,a first direction dimension D1[12c] of the third face portion12c,and a first direction dimension D1[12d] of the fourth face portion12dare equal to or substantially equal to a maximum value of a first direction dimension D1[12e] of the fifth face portion12e.

As will be explained later with reference toFIGS. 8A, 8B and 8C, first direction dimensions D1[12b′&12c] of a second face portion12b′ and a third face portion12c′ can be made larger than the first direction dimensions D1[12d&12e] of the fourth face portion12dand the fifth face portion12e.

In addition, at least one of or preferably both of the edges of the fourth face portion12dand the fifth face portion12ehave recess portions12d1and12e1recessed from the edges toward the first face portion12a.Both side portions in the third direction d3of the recess portions12d1and12e1are covering portions12d2and12e2for covering the ridge portions RP on the two faces in the second direction d2of the component body11.

That means, since the fourth face portion12dis continuous with the second face portion12band the third face portion12c,the continuous part is the covering portion12d2for covering the ridge portion RP, and since the fifth face portion12eis also continuous with the second face portion12band the third face portion12c,the continuous part is the covering portion12e2for covering the ridge portion RP.

Incidentally, a shape of the recess portions12d1and12e1viewed from the second direction d2is rectangular.

As will explained later with reference toFIGS. 7A and 7B, recess portions12d3and12e3and recess portions12d5and12e5viewed from the second direction d2may be V-shaped or U-shaped.

Furthermore, the recess portion12d1is preferably formed at the middle in the third direction d3of the edge of the fourth face portion12d,and the recess portion12e1is preferably formed at the middle in the third direction d3of the edge of the fifth face portion12e.The reason why it is preferable to form the recess portion at the middle of the third direction d3is because third direction dimensions D3[12d2] of the covering portions12d2present on both sides in the third direction d3of the recess portion12d1should be equal to each other as much as possible, and the third direction dimensions D3[12e2] of the covering portions12e2present on both sides in the third direction d3of the recess portion12e1should be equal to each other as much as possible.

The first direction dimensions D1[12b,12c,12d&12e] of the second face portion12b,the third face portion12c,the fourth face portion12d,and the fifth face portion12ecan be, e.g., within a range of 1/10 to 4/10 of the first direction dimension D1[11] of the component body11.

In a case where the ceramic electronic component10is mounted on a circuit board CB (seeFIG. 5), the second face portion12bor the third face portion12cfaces a conductive pad CBa of the circuit board CB, and therefore the first direction dimensions D1[12b&12c] of the second face portion12band the third face portion12care preferably ensured to be at least 50 μm. In addition, for the purpose of avoiding short-circuiting between the second face portions12bor between the third face portions12cdue to a solder SOL in the soldering process during mounting, a distance between the second face portions12bin the first direction and a distance between the third face portions12cin the first direction are preferably ensured to be at least 100 μm.

First direction dimensions D1[12d1&12e1] of the recess portions12d1and12e1can be, e.g., within a range of 5% to 95% of the first direction dimensions D1[12d&12e] of the fourth face portion12dand the fifth face portion12e.When the first direction dimensions D1[12d1&12e1] of the recess portions12d1and12e1are smaller than 5% of the first direction dimensions D1[12d&12e] of the fourth face portion12dand the fifth face portion12e,an effect described below (suppression of crack extension) is hardly obtained, and when they are larger than 95%, area ratios of the recess portions12d1and12e1are large, and therefore a desired strength of the fourth face portion12dand the fifth face portion12eis hardly obtained.

When emphasizing suppression of the crack extension, the first direction dimensions D1[12d1&12e1] of the recess portions12d1and12e1are within a range of 5% to 15%, preferably 15% to 65%, more preferably 65% to 95% of the first direction dimensions D1[12d&12e] of the fourth face12dportion and the fifth face portion12e.

The ranges of the third direction dimensions D3[12d1&12e1] of the open ends of the recess portions12d1and12e1are not particularly limited as long as they are smaller than the third direction dimensions D3[12d&12e] of the fourth face portion12dand the fifth face portion12e,in other words, as long as the covering portions12d2and12e2are present on both sides in the third direction d3of the recess portions12d1and12e1. In addition, the third direction dimensions at the middle in the first direction between the open end and the impasse portion of the recess portions12d1and12e1are preferably 40% to 95%, more preferably 50% to 85% of the third direction dimensions of the fourth face portion12dand the fifth face portion12e.

Thicknesses of the first face portion12a,the second face portion12b,the third face portion12c,the fourth face portion12d,and the fifth face portion12eof the external electrode12can be, e.g., within a range of 10 to 18 μm, or 2 to 10 μm in consideration of low-height mounting (low mounting height) of the ceramic electronic component10.

In addition, the external electrode12has a multilayer structure including a base conductor layer and at least one covering conductor layer for covering the surface of the base conductor layer. The number of the covering conductor layer is not particularly limited, but may be, e.g., 1 to 4 in light of a balance with the thickness of each face portion12ato12eof the external electrode12. The main ingredient of the external electrode12will be explained in the following examples of a manufacturing method including a layer configuration and a formation procedure.

Herein, a preferable example of the manufacturing method for the aforementioned ceramic electronic component10, particularly a preferable example of the production method for the external electrode12will be explained.

The ceramic electronic component10is manufactured mainly bya process for producing the component body11, anda process for producing the external electrodes12on each end portion in the first direction dl of the component body11.

The process for producing the component body11includes: a step of forming a multiple-patterning unbaked multilayer sheet by appropriately laminating and pressure-bonding a ceramic green sheet having no internal electrode layer pattern and a ceramic green sheet having the internal electrode layer pattern; a step of forming a unbaked chip corresponding to the component body11by chopping the unbaked multilayer sheet; a step of grinding the unbaked chip; and a step of baking the unbaked chip under an atmosphere and temperature profile according to a ceramic material and a metal material.

The process of producing the external electrode12includes: a step of forming the base conductor layer on the surface of the component body; and a step of forming at least one covering conductor layer on the surface of the base conductor layer. In a case where there are two or more covering conductor layers, the first covering conductor layer is formed on the surface of the base conductor layer, and the second and subsequent covering conductor layers are sequentially formed on the surface of the antecedently formed covering conductor layer.

As an example, a case where the external electrode12has a four-layer configuration will be explained in detail with reference toFIGS. 4A and 4B(internal electrode layers11aare not illustrated). First, a base conductor layer CF1having a shape corresponding to the first face portion12a,the second face portion12b,the third face portion12c,the fourth face portion12d,and the fifth face portion12eis formed on the surface of the component body11. A shape of a recess portion CF1aof the base conductor layer CF1viewed from the second direction d2is slightly smaller than the recess portions12d1and12e1of the fourth face portion12dand the fifth face portion12e.Then, a first covering conductor layer CF2is formed on the surface of the base conductor layer CF1, a second covering conductor layer CF3is formed on the surface of the first covering conductor layer CF2, and a third covering conductor layer CF4is formed on the surface of the second covering conductor layer CF3.

For forming the base conductor layer CF1and the respective covering conductor layers CF2to CF4, the following methods can be selectively adopted: a so-called baking method in which a metal paste containing at least a metal powder, an organic solvent and a synthetic resin binder is applied by a procedure such as a screen printing method and a dipping method, dried and then baked; a dry plating method such as sputtering and vacuum deposition; and a wet plating method such as electroplating or electroless plating. In light of a balance with the thicknesses of the respective face portions12ato12eof the external electrode12, particularly with the thicknesses of the second face portion12band the third face portion12c,it is preferable that the base conductor layer CF1is formed by using the baking method and sputtering in combination or by sputtering, and the respective covering conductor layers CF2to CF4are formed by electroplating in consideration of mass productivity.

In a case where forming the base conductor layer CF1by using the baking method and sputtering in combination, the main ingredients of the baked film and the sputtered film can be, e.g., metals such as copper, nickel, silver, gold, platinum, palladium, tin, chromium, titanium, tantalum, tungsten, molybdenum, and an alloy thereof.

When forming the base conductor layer CF1by using the baking method and sputtering in combination, first, a baked film is formed on one face in the first direction d1of the component body11so that the periphery portion slightly wraps two faces in the second direction d2and two faces in the third direction d3, and subsequently a sputtered film which is continuous with the baked film and has the recess portion CF1adepicted inFIG. 4Ais formed on the two faces in the second direction d2and the two faces in the third direction d3of the component body11, and this sputtered film is used as the base conductor layer CF1. In a case where a desired sputtered film is hardly formed by single sputtering, the sputtering may be conducted twice or more by changing the direction of the component body11, or the like.

On the other hand, in a case where the base conductor layer CF1is formed by sputtering, the main ingredient of the sputtered film can be, e.g., the same metal as described above.

When forming the base conductor layer CF1by sputtering, a sputtered film having the recess portion CF1adepictedFIG. 4Ais formed on one face in the first direction d1, two faces in the second direction d2, and two faces in the third direction d3of the component body11, and this sputtered film is used as the base conductor layer CF1. In a case where a desired sputtered film is hardly formed by single sputtering, the sputtering may be conducted twice or more by changing the direction of the component body11, or the like.

There is no remarkable quality difference between the case of forming the base conductor layer CF1by using the baking method and sputtering in combination and the case of forming the base conductor layer CF1by sputtering. However, so to speak, in the former case, an adhesiveness of the base conductor layer CF1to the component body11can be enhanced by the baked film included in the base conductor layer CF1. On the other hand, in the latter case, the base conductor layer CF1can be formed only by sputtering, contributing to reduction of steps.

In a case where the respective covering conductor layers CF2to CF4are formed by electroplating, the main ingredient of the respective covering conductor CF2to CF4can be, e.g., the same main ingredient as of the base conductor layer CF1, but, in consideration of mutual adhesiveness, the main ingredient of the first covering conductor layer CF2may be different from the main ingredient of the base conductor layer CF1, the main ingredient of the second covering conductor layer CF3may be different from the main ingredient of the first covering conductor layer CF2, and the main ingredient of the third covering conductor layer CF3may be different from the main ingredient of the second covering conductor layer CF2.

As an example, the main ingredient can be a combination of nickel as the main ingredient of the base conductor layer CF1, copper as the main ingredient of the first covering conductor layer CF2, nickel as the main ingredient of the second covering conductor layer CF3, tin as the main ingredient of the third covering conductor layer CF4.

Also in a case where the external electrode12has a two-layer configuration, a three-layer configuration, or a five-layer configuration different from the aforementioned four-layer configuration, the formation method and the main ingredients of the base conductor layer and the covering conductor layer are the same as in the four-layer configuration. In a case where the external electrodes12are connected to the conductive pad CBa of the circuit board CB using the solder SOL (seeFIG. 5), the main ingredient of the outermost covering conductor layer of the external electrode12having a two- to five-layer configuration is preferably tin which is most compatible with solder.

When the aforementioned ceramic electronic component10is mounted on the circuit board CB, a soldering paste is applied to conductive pads CBa corresponding to the external electrodes12disposed on the circuit board CB by printing or the like, and the ceramic electronic component10is installed so that the third face portion12cof the external electrode12contacts the soldering paste, as depicted inFIG. 5(a case where the lower face inFIG. 5in the third direction d3of the ceramic electronic component10is used as the mounting face). Subsequently, the circuit board CB equipped with the ceramic electronic component10is put into a reflow furnace (not depicted in the figure), and then, through a preheating step, a main heating step and a cooling step, the external electrodes12are connected to the conductive pad CBa via the solder SOL.

In the aforementioned ceramic electronic component10mounted on the circuit board CB, as depicted inFIG. 6, when an external force is applied to the ceramic electronic component10so as to bend the ceramic electronic component10in a direction intersecting with the first direction dl due to deflection of the circuit board CB (see two-dot chain lines inFIG. 6) and the like based on thermal expansion/contraction, external force application, or the like, stress concentrates to positions marked with x on the ceramic electronic component10inFIG. 6.

Although the stress concentration can generally cause cracks, stress transmission in the third direction d3can be dispersed by the recess portions12d1and12e1even if the stress concentrates to the positions marked with x inFIG. 6, because the recess portions12d1and12e1recessed from the edge toward the first face portion12aare formed on at least one edge, preferably both edges of the fourth face portion12dand the fifth face portion12eof the external electrode12. Thus, it is hard to cause a so-called crack extension phenomenon in which cracks extend straight in the third direction d3on two faces in the second direction d2of the component body11.

Furthermore, in a case where the recess portions12d1and12e1are on at least one edge, preferably both edges of the fourth face portion12dand the fifth face portion12eof the external electrode12, the molten solder spreads up to the surfaces of the recess portions12d2and12e2of the fourth face portion12dand the fifth face portion12e,but the up-spreading is likely to be blocked by the recess portions12d1and12e1. That means, in a case where the up-spreading is blocked, the solder SOL adheres to the surfaces of the fourth face portion12dand the fifth face portion12eof the external electrode12while avoiding the recess portions12d1and12e1, as depicted inFIG. 5. Thus, this aspect can mitigate transmission in the third direction d3of the stress concentrating to the positions marked with x inFIG. 6, and further suppress occurrence of the crack extension phenomenon.

In addition, in a case where the recess portions12d1and12e1are on at least one edge, preferably on both edges of the fourth face portion12dand the fifth face portion12eof the external electrode12, the solder SOL bridges between the fourth face portions12dor between the fifth face portions12eto enhance a possibility to avoid conduction between the fourth face portion12dand the fifth face portion12evia the recess portions12d1and12e1in the soldering process, and also enhance a possibility to avoid conduction between the fourth face portion12dand the fifth face portion12evia the recess portions12d1and12e1on the basis of the migration.

Furthermore, in a case where the recess portions12d1and12e1are on at least one edge, preferably on both edges of the fourth face portion12dand the fifth face portion12eof the external electrode12, the ridge portions RP on the two faces in the second direction of the component body11can be prevented from cracking compared to the case of no covering portions12d2and12e2in a distribution process, a mounting process or the like of the ceramic electronic component10, because the covering portions12d2and12e2for covering the ridge portions RP of the two faces in the second direction d2of the component body11along the ridge portions RP are disposed on the both sides in the third direction d3.

FIGS. 7A and 7Bdepict modification examples of the shapes of the recess portions12d1and12e1formed on the fourth face portion12dand the fifth face portion12eof the external electrode12of the ceramic electronic component10. The recess portions12d3and12e3viewed from the second direction d2depicted inFIG. 7Aare V-shaped, and shapes of covering portions12d4and12e4on both sides in the third direction d3are also slightly changed along with the V-shape. To explain the V-shape in other words, an angle formed by two straight lines running from the open end toward the end portion in the first direction is less than 90 degrees in the recess portion. In addition, the recess portions12d5and12e5viewed from the second direction d2depicted inFIG. 7Bare U-shaped, and shapes of covering portions12d6and12e6on both sides in the third direction d3are also slightly changed along with the U-shape. To explain the U-shape in other words, the impasse portion is curved on the recess portion.

In a case where the rectangular recess portions12d1and12e1formed on the fourth face portion12dand the fifth face portion12eof the external electrode12of the aforementioned ceramic electronic component10are replaced by the V-shaped recess portions12d3and12e3depicted inFIG. 7A, and also replaced by the U-shaped recess portions12d5and12e5depicted inFIG. 7B, the same effect as described above can be obtained.

FIGS. 8A, 8B and 8Cdepict modification examples of the shapes of the second face portion12band the third face portion12cof the external electrode12of the ceramic electronic component10. The first direction dimensions D1[12b′&12c] of the second face portion12b′ and the third face portion12c′ depicted inFIGS. 8A, 8B and 8Care larger than the first direction dimensions D1[12d&12e] of the fourth face portion12dand the fifth face portion12e.Ranges of values obtained by subtracting the first direction dimensions D1[12d&12e] from the first direction dimensions D1[12b′&12c′], i.e., ranges of first direction dimensions D1[12b1&12c1] of an overhang portion12b1of the second face portion12b′ and an overhang portion12c1of the third face portion12c′ can be, e.g., 1/20 to 1/2 of the first direction dimensions D1[12d&12e] of the fourth face portion12dand the fifth face portion12e.

In addition, in a case where the first direction dimensions D1[12b′&12c] of the second face portion12b′ and the third face portion12c′ are larger than the first direction dimensions D1[12d&12e] of the fourth face portion12dand the fifth face portion12e,the roundness of the two corners (symbol is omitted) on the edge sides of the second face portion12b′ and the third face portion12c′ can be made larger than the roundness of the two corners (symbol is omitted) on the side of the first face portion12a.

Even in a case where the second face portion12band the third face portion12cof the external electrode12on the aforementioned ceramic electronic component10are changed to the second face portion12b′ and the third face portion12c′ depicted inFIGS. 8A, 8B and 8C, the same effect as described above can be obtained.

Although the ceramic electronic component10in which the present disclosure is applied to the multilayer ceramic capacitor has been explained above, the present disclosure can also be applied to ceramic electronic components other than the multilayer ceramic capacitor, e.g., a multilayer ceramic varistor, a multilayer ceramic inductor, or the like. That means, as long as the ceramic electronic component falls under the LW-reversed type described in BACKGROUND and also corresponds to the low-height mounting (low mounting height), the present disclosure can be applied to the ceramic electronic component to obtain the same effect as described above.

The present disclosure contains subject matter related to that disclosed in Japanese Priority Patent Application JP 2018-193502 filed in the Japan Patent Office on Oct. 12, 2018, the entire content of which is hereby incorporated by reference.