JP7495785B2 - Multilayer ceramic electronic components - Google Patents

Description

The present invention relates to multilayer ceramic electronic components used, for example, as multilayer ceramic capacitors, and more specifically to multilayer ceramic electronic components that can be made thin.

For example, as shown in Patent Document 1 below, conventional multilayer ceramic capacitors have terminal electrodes at both longitudinal ends of the element body, and each terminal electrode typically has an end electrode portion of the element body, an upper electrode portion covering the upper surface of the element body, and a lower electrode portion covering the lower surface of the element body.

The base electrode of the terminal electrode is formed by immersing the end of the element body in a solution containing conductive particles. During immersion, multiple element bodies are inserted into multiple holding holes formed in a holding plate, and one end of each element body is immersed in the solution to form the base electrode. After that, if necessary, a plating film is formed on the base electrode to form the terminal electrode.

In any case, when forming the terminal electrodes on the element body, if the element body itself does not have a certain degree of thickness, it is difficult to form the base electrode and also difficult to form the plating film. In other words, if the element body is thin, it is likely to be damaged when the element body is held in the holding hole of the holding plate. In addition, if the element body is thin, it is likely to be damaged when plating is performed. Therefore, with the structure of conventional multilayer ceramic capacitors, it is difficult to make the element body thin, and therefore it is difficult to make the multilayer ceramic capacitor low-profile.

For example, the multilayer ceramic capacitor described in Patent Document 2 below does not have a first external electrode or a second external electrode on one side in the lamination direction (height direction) of the dielectric layers and the internal electrode layers. This allows the height dimension of the capacitor body to be increased, which contributes to an increase in capacitance.

However, Patent Document 2 does not consider how to improve the strength of the element body as the height of the multilayer ceramic capacitor is reduced.

JP 2017-28254 A JP 2017-152621 A

The present invention was made in consideration of these circumstances, and its purpose is to provide a multilayer ceramic electronic component, such as a multilayer ceramic capacitor, that can be made low-profile.

In order to achieve the above object, a multilayer ceramic electronic component according to a first aspect of the present invention comprises:
an element body in which internal electrode layers and insulating layers, which are substantially parallel to a plane including the first axis and the second axis, are alternately laminated along a third axis;
a terminal electrode formed in close contact with an outer surface of the element body and electrically connected to the internal electrode layer,
the terminal electrode has a pair of end-side electrode portions covering an end portion of the element body in the second axial direction from which the internal electrode layer is drawn out and facing each other in the direction of the second axis, and a pair of upper electrode portions each continuously covering a portion of an upper surface of the element body substantially perpendicular to the third axis, the pair of upper electrode portions being continuous with the end-side electrode portions,
The outer surface of the end electrode portion is covered with an end covering layer,
The terminal electrode is substantially absent on a lower surface of the element body that is located on the opposite side along the third axis to the upper surface of the element body.

A multilayer ceramic electronic component according to a second aspect of the present invention comprises:
an element body in which internal electrode layers and insulating layers, which are substantially parallel to a plane including the first axis and the second axis, are alternately laminated along a third axis;
a terminal electrode formed in close contact with an outer surface of the element body and electrically connected to the internal electrode layer,
the terminal electrode has a pair of end-side electrode portions covering the end portions of the element body in the second axis direction from which the internal electrode layers are drawn out and facing each other in the second axis direction, and a pair of upper electrode portions each continuously covering a portion of an upper surface of the element body substantially perpendicular to the third axis, the pair of upper electrode portions being continuous with the end-side electrode portions,
The outer surface of the end electrode portion is covered with an end covering layer,
The element body is characterized in that the entire lower surface of the element body, which is located on the opposite side of the upper surface along the third axis, is exposed to the outside.

In the multilayer ceramic electronic component according to the first aspect of the present invention and the multilayer ceramic electronic components according to the third and fifth aspects described below, terminal electrodes are not substantially formed on the underside of the element body. In the multilayer ceramic electronic component according to the second aspect of the present invention and the multilayer ceramic electronic components according to the fourth and sixth aspects described below, the entire underside of the element body is exposed. In the structure of conventional multilayer ceramic electronic components, simply reducing the thickness of the element body to, for example, about 100 μm or less makes it difficult to form terminal electrodes on the element body.

The multilayer ceramic electronic components according to the first and second aspects of the present invention, as well as the multilayer ceramic electronic components according to the third to sixth aspects described below, can be formed, for example, by combining two or more thin element bodies, forming terminal electrodes, and then separating the element bodies. Therefore, multilayer ceramic electronic components that are, for example, half or less the thickness of conventional ones, can be easily manufactured.

In the resulting multilayer ceramic electronic component, substantially no terminal electrodes are formed on the underside of the element body, or the entire underside of the element body is exposed. The total thickness of the multilayer ceramic electronic component can be reduced to 100 μm or less, preferably 90 μm or less, more preferably 80 μm or less, and particularly preferably 60 μm or less, which contributes to a reduction in the height of the multilayer ceramic electronic component.

In addition, in the multilayer ceramic electronic components according to the first and second aspects of the present invention, the outer surfaces of the end electrode portions are covered with end coating layers. This makes it possible to improve the moisture resistance of the multilayer ceramic electronic component. That is, even if the terminal electrodes become thinner due to the lowering of the height of the multilayer ceramic electronic component, it is possible to prevent moisture from entering the interior of the multilayer ceramic electronic component. As a result, even if the multilayer ceramic electronic component is used in a moist or humid environment, or if the manufacturing process for the multilayer ceramic electronic component includes a process using water or a wet process, it is possible to prevent moisture from entering the interior of the multilayer ceramic electronic component and suppress deterioration of insulation.

Furthermore, in the multilayer ceramic electronic components according to the first and second aspects of the present invention, the outer surfaces of the end electrode portions are covered with end coating layers, thereby increasing their strength.

In the multilayer ceramic electronic components according to the first and second aspects of the present invention, the lower surface of the element body is preferably a flat surface. The flat lower surface of the element body makes it easier to embed the element body, for example, inside a substrate. Furthermore, when the flat lower surface of the element body is placed on a mounting surface, the element body is attached in close contact with the mounting surface, improving the bending strength of the multilayer ceramic electronic component.

In the multilayer ceramic electronic components according to the first and second aspects of the present invention, the coverage ratio, expressed as (coverage area of the end-side covering layer/area of the outer surface of the end-side electrode portion) x 100, is preferably 96 to 100%.

By having a coverage rate equal to or greater than a specified value, the moisture resistance of the multilayer ceramic electronic component can be further improved, and its strength can also be increased.

In the multilayer ceramic electronic components according to the first and second aspects of the present invention, the relative thickness of the end coating layer, expressed as (average thickness of the end coating layer/average thickness of the end electrode portion) x 100, is preferably 20 to 500%.

By having the relative thickness of the end coating layer fall within the above range, the moisture resistance of the multilayer ceramic electronic component can be further improved, the strength can be increased, and the dimension of the multilayer ceramic electronic component in the direction of the second axis does not become too large, allowing for problem-free mounting.

In the multilayer ceramic electronic components according to the first and second aspects of the present invention, the material of the end-side coating layer is preferably a film mainly composed of glass or resin containing Si as a main component.

This makes it possible to further improve the moisture resistance of the multilayer ceramic electronic components and increase their strength.

In the multilayer ceramic electronic component according to the first and second aspects of the present invention, the multilayer ceramic electronic component preferably has a predetermined upper surface coating layer between a pair of upper electrode portions. The predetermined upper surface coating layer is provided on the multilayer ceramic electronic component in such a manner that the surface of the upper surface coating layer covering the upper surface of the element body located between the pair of upper electrode portions is in close contact with the surface of the upper electrode portion so as to be substantially flush with the surface of the upper electrode portion. This reduces the step on the upper surface side of the element body, and suppresses stress concentration at the step even when the multilayer ceramic electronic component is made low-profile, thereby increasing the bending strength of the multilayer ceramic electronic component.

In addition, by improving the bending strength, it becomes easier to increase the dimension of the element body in the direction of the first axis or the dimension in the direction of the second axis, and the opposing area between the internal electrode layers inside the element body becomes larger, improving the characteristics of the electronic component, such as the capacitance.

As mentioned above, if there is no step on the top surface of the element body where the upper electrode portion is formed, the multilayer ceramic capacitor can be easily picked up by vacuum adsorption and embedded in the substrate.

In the multilayer ceramic electronic components according to the first and second aspects of the present invention, the surface of the upper electrode portion is preferably covered with at least one selected from Ni plating, Sn plating, Au plating, and Cu plating.

In the multilayer ceramic electronic components according to the first and second aspects of the present invention, the element body may include an upper surface reinforcement layer below the upper electrode portion and the upper surface coating layer.

This configuration not only improves the bending strength of the multilayer ceramic electronic component, but also further suppresses cracks and breakage during subsequent processes.

In order to achieve the above object, a multilayer ceramic electronic component according to a third aspect of the present invention comprises:
an element body in which internal electrode layers and insulating layers, which are substantially parallel to a plane including the first axis and the second axis, are alternately laminated along a third axis;
a terminal electrode formed in close contact with an outer surface of the element body and electrically connected to the internal electrode layer,
the terminal electrode has a pair of end-side electrode portions covering an end portion of the element body in the second axial direction from which the internal electrode layer is drawn out and facing each other in the direction of the second axis, and a pair of upper electrode portions each continuously covering a portion of an upper surface of the element body substantially perpendicular to the third axis, the pair of upper electrode portions being continuous with the end-side electrode portions,
a conductive metal film is interposed between the element body and the terminal electrode;
The terminal electrode is substantially absent on a lower surface of the element body that is located on the opposite side along the third axis to the upper surface of the element body.

A multilayer ceramic electronic component according to a fourth aspect of the present invention comprises:
an element body in which internal electrode layers and insulating layers, which are substantially parallel to a plane including the first axis and the second axis, are alternately laminated along a third axis;
a terminal electrode formed in close contact with an outer surface of the element body and electrically connected to the internal electrode layer,
the terminal electrode has a pair of end-side electrode portions covering the end portions of the element body in the second axis direction from which the internal electrode layers are drawn out and facing each other in the second axis direction, and a pair of upper electrode portions each continuously covering a portion of an upper surface of the element body substantially perpendicular to the third axis, the pair of upper electrode portions being continuous with the end-side electrode portions,
a conductive metal film is interposed between the element body and the terminal electrode;
The element body is characterized in that the entire lower surface of the element body, which is located on the opposite side of the upper surface along the third axis, is exposed to the outside.

In addition, in the multilayer ceramic electronic components according to the third and fourth aspects of the present invention, a conductive metal film is interposed at the interface between the element body and the terminal electrode. This configuration can improve the adhesion between the terminal electrode and the surface of the element body. As a result, improved adhesion between the terminal electrode and the element body can be achieved, and moisture resistance can be improved.

In the multilayer ceramic electronic components according to the third and fourth aspects of the present invention, the lower surface of the element body is preferably a flat surface. The flat lower surface of the element body makes it easier to embed the element body, for example, inside a substrate. Furthermore, when the flat lower surface of the element body is placed on the mounting surface, the element body is attached in close contact with the mounting surface, improving the bending strength of the multilayer ceramic electronic component.

In the multilayer ceramic electronic components according to the third and fourth aspects of the present invention, the conductive metal film preferably contains at least one of the metals Pt, Rh, Ru, Re, Ir, and Pd. By forming a conductive metal film using such a metal on the surface of the element body, the adhesion between the terminal electrode and the surface of the element body can be further improved.

In the multilayer ceramic electronic components according to the third and fourth aspects of the present invention, the coverage area ratio of the uneven surface formed on the surface of the element body covered by the conductive metal film is preferably within the range of 20 to 70%. If the coverage area ratio of the surface of the element body covered by the conductive metal film is too small or too large, the effect of improving the adhesion between the terminal electrode and the element body is small, and if the coverage area ratio is within the range of 20 to 70%, the effect of improving the adhesion is large.

In the multilayer ceramic electronic components according to the third and fourth aspects of the present invention, the outer surfaces of the end electrode portions of the terminal electrodes are preferably covered with end coating layers. This can further improve the moisture resistance of the multilayer ceramic electronic components. That is, even if the terminal electrodes are made thinner by reducing the height of the multilayer ceramic electronic components, it is possible to prevent moisture from entering the interior of the multilayer ceramic electronic components. As a result, even if the multilayer ceramic electronic components are used in environments with moisture or high humidity, or even if the manufacturing process for the multilayer ceramic electronic components includes a process using water or a wet process, it is possible to prevent moisture from entering the interior of the multilayer ceramic electronic components and suppress deterioration of insulation.

In addition, the outer surfaces of the end electrodes are covered with end coating layers, which further increases the strength of the multilayer ceramic electronic component.

In the multilayer ceramic electronic components according to the third and fourth aspects of the present invention, the coverage ratio, expressed as (coverage area of the end-side covering layer/area of the outer surface of the end-side electrode portion) x 100, is preferably 96 to 100%.

By having a coverage rate equal to or greater than a specified value, the moisture resistance of the multilayer ceramic electronic component can be further improved, and its strength can also be increased.

In the multilayer ceramic electronic components according to the third and fourth aspects of the present invention, the relative thickness of the end coating layer, expressed as (average thickness of the end coating layer/average thickness of the end electrode portion) x 100, is preferably 20 to 500%.

By having the relative thickness of the end coating layer fall within the above range, the moisture resistance of the multilayer ceramic electronic component can be further improved, the strength can be increased, and the dimension of the multilayer ceramic electronic component in the direction of the second axis does not become too large, allowing for problem-free mounting.

In the multilayer ceramic electronic components according to the third and fourth aspects of the present invention, the material of the end-side coating layer is preferably a film mainly composed of glass or resin containing Si as a main component.

This makes it possible to further improve the moisture resistance of the multilayer ceramic electronic components and increase their strength.

In the multilayer ceramic electronic component according to the third and fourth aspects of the present invention, the multilayer ceramic electronic component preferably has a predetermined upper surface coating layer between a pair of upper electrode portions. The predetermined upper surface coating layer is provided on the multilayer ceramic electronic component in such a manner that the surface of the upper surface coating layer covering the upper surface of the element body located between the pair of upper electrode portions is in close contact with the surface of the upper electrode portion so as to be substantially flush with the surface of the upper electrode portion. This reduces the step on the upper surface side of the element body, and even if the multilayer ceramic electronic component is made low-profile, it is possible to suppress the concentration of stress at the step, and it is possible to increase the bending strength of the multilayer ceramic electronic component.

In addition, by improving the bending strength, it becomes easier to increase the dimension of the element body in the direction of the first axis or the dimension in the direction of the second axis, and the opposing area between the internal electrode layers inside the element body becomes larger, improving the characteristics of the electronic component, such as the capacitance.

As mentioned above, if there is no step on the top surface of the element body where the upper electrode portion is formed, the multilayer ceramic capacitor can be easily picked up by vacuum adsorption and embedded in the substrate.

In the multilayer ceramic electronic components according to the third and fourth aspects of the present invention, the surface of the upper electrode portion is preferably covered with at least one selected from Ni plating, Sn plating, Au plating, and Cu plating.

In the multilayer ceramic electronic components according to the third and fourth aspects of the present invention, the element body may include an upper surface reinforcement layer below the upper electrode portion and the upper surface coating layer.

This configuration not only improves the bending strength of the multilayer ceramic electronic components, but also further suppresses cracks and breakage during subsequent processes.

In order to achieve the above object, a multilayer ceramic electronic component according to a fifth aspect of the present invention comprises:
an element body in which internal electrode layers and insulating layers, which are substantially parallel to a plane including the first axis and the second axis, are alternately laminated along a third axis;
a terminal electrode formed in close contact with an outer surface of the element body and electrically connected to the internal electrode layer,
the terminal electrode has a pair of end-side electrode portions covering the end portions of the element body in the second axis direction from which the internal electrode layers are drawn out and facing each other in the second axis direction, and a pair of upper electrode portions each continuously covering a portion of an upper surface of the element body substantially perpendicular to the third axis, the pair of upper electrode portions being continuous with the end-side electrode portions,
the terminal electrode is substantially absent on a lower surface of the element body that is located on the opposite side of the upper surface of the element body along the third axis;
The element body has a reinforcing layer;
the reinforcing layer covers at least one of a pair of side surfaces facing each other in the first axis direction of the element body, the upper surface, and the lower surface;
the reinforcing layer comprises a filler and a matrix;
The filler is made of glass or alumina.
The filler has a needle-like, columnar or plate-like shape.

In order to achieve the above object, a multilayer ceramic electronic component according to a sixth aspect of the present invention comprises:
an element body in which internal electrode layers and insulating layers, which are substantially parallel to a plane including the first axis and the second axis, are alternately laminated along a third axis;
a terminal electrode formed in close contact with an outer surface of the element body and electrically connected to the internal electrode layer,
the terminal electrode has a pair of end-side electrode portions covering the end portions of the element body in the second axis direction from which the internal electrode layers are drawn out and facing each other in the second axis direction, and a pair of upper electrode portions each continuously covering a portion of an upper surface of the element body substantially perpendicular to the third axis, the pair of upper electrode portions being continuous with the end-side electrode portions,
The entire lower surface of the element body, which is located on the opposite side of the upper surface of the element body along the third axis, is exposed to the outside,
The element body has a reinforcing layer;
the reinforcing layer covers at least one of a pair of side surfaces facing each other in the first axis direction of the element body, the upper surface, and the lower surface;
the reinforcing layer comprises a filler and a matrix;
The filler is made of glass or alumina.
The filler has a needle-like, columnar or plate-like shape.

In addition, in the multilayer ceramic electronic components according to the fifth and sixth aspects of the present invention, at least one of the side, top, and bottom surfaces of the element body has a reinforcing layer containing needle-shaped, columnar, or plate-shaped fillers of a predetermined material. This can increase the bending strength of the multilayer ceramic electronic component.

In addition, the improved bending strength makes it easier to lengthen the dimension of the element body in the first axis direction or the dimension in the second axis direction, increasing the opposing area between the internal electrode layers inside the element body, improving the characteristics of the electronic component, such as capacitance.

The multilayer ceramic electronic components according to the fifth and sixth aspects of the present invention may have the reinforcing layer covering the upper surface of the element body.

In this way, the reinforcement layer covering the upper surface is formed in contact with the upper electrode portion, which improves adhesion between the element body and the terminal electrode, and tends to provide excellent moisture resistance from the upper surface.

In the multilayer ceramic electronic components according to the fifth and sixth aspects of the present invention, the material of the substrate may be at least one selected from glass and resin.

By using at least one substrate material selected from glass and resin, the bending strength of the multilayer ceramic electronic component can be increased.

In the multilayer ceramic electronic components according to the fifth and sixth aspects of the present invention, the reinforcing layer covering the top surface and the reinforcing layer covering the side surfaces may continuously cover the element body.

The reinforcing layer covering the top surface and the reinforcing layer covering the sides continuously cover the element body, making it possible to increase the bending strength of the multilayer ceramic electronic component.

The multilayer ceramic electronic components according to the fifth and sixth aspects of the present invention may be such that the surface of an upper surface coating layer covering the upper surface of the element body located between a pair of the upper electrode portions is in close contact with the surface of the upper electrode portions so as to be substantially flush with the surface of the upper electrode portions.

This reduces the step on the top surface of the element body, suppressing the concentration of stress on the step even when the multilayer ceramic electronic component is made thinner, and increasing the bending strength of the multilayer ceramic electronic component.

As mentioned above, there is no step on the top surface of the element body where the upper electrode portion is formed. This makes it easy to pick up the multilayer ceramic electronic component by vacuum suction and to embed it in the substrate.

In the multilayer ceramic electronic components according to the fifth and sixth aspects of the present invention, the outer surfaces of the end electrode portions may be covered with end coating layers.

By covering the outer surface of the end electrode portion with the end coating layer, the moisture resistance of the multilayer ceramic electronic component can be improved. In other words, even if the terminal electrodes become thinner due to the lower height of the multilayer ceramic electronic component, it is possible to prevent moisture from entering the interior of the multilayer ceramic electronic component. As a result, even if the multilayer ceramic electronic component is used in a moist or humid environment, or if the manufacturing process for the multilayer ceramic electronic component includes a process that uses water or a wet process, it is possible to prevent moisture from entering the interior of the multilayer ceramic electronic component and suppress a decrease in insulation.

In the multilayer ceramic electronic components according to the fifth and sixth aspects of the present invention, the lower surface of the element body may be a flat surface.

The multilayer ceramic electronic component according to the fifth and sixth aspects of the present invention has the reinforcing layer covering the lower surface, and the outer surface of the reinforcing layer covering the lower surface may be a flat surface.

The surface of the lower surface or the outer surface of the reinforcing layer covering the lower surface is flat, which makes it easier to embed the component inside a substrate, for example. In addition, when the surface of the lower surface or the flat outer surface of the reinforcing layer covering the lower surface is placed on the mounting surface, the multilayer ceramic electronic component is attached in close contact with the mounting surface, improving the bending strength of the multilayer ceramic electronic component.

In the multilayer ceramic electronic components according to the fifth and sixth aspects of the present invention, the particle diameter of the filler in the minor axis direction is 0.1 μm or more and 3.0 μm or less,
The particle size of the filler in the major axis direction is 0.5 μm or more and 15.0 μm or less,
The aspect ratio (%) of the filler, expressed as (particle diameter in the minor axis direction/particle diameter in the major axis direction)×100, may be 0.7% or more and 60% or less.

This increases the bending strength of the multilayer ceramic electronic component. In addition, if the multilayer ceramic electronic component has a reinforcing layer on the upper surface of the element body, the adhesion between the reinforcing layer covering the upper surface and the upper electrode portion can be increased, thereby improving the moisture resistance of the multilayer ceramic electronic component.

In the multilayer ceramic electronic components according to the fifth and sixth aspects of the present invention, the content of the filler in the reinforcement layer may be 30% by volume or more and 80% by volume or less.

This increases the bending strength of the multilayer ceramic electronic component. In addition, if the multilayer ceramic electronic component has a reinforcing layer on the upper surface of the element body, the adhesion between the reinforcing layer covering the upper surface and the upper electrode portion can be increased, thereby improving the moisture resistance of the multilayer ceramic electronic component.

In the multilayer ceramic electronic components according to the fifth and sixth aspects of the present invention, the substrate material may be glass containing at least one of Si and Al as a main component.

This increases the bending strength of the multilayer ceramic electronic component. In addition, if the multilayer ceramic electronic component has a reinforcing layer on the upper surface of the element body, the adhesion between the reinforcing layer covering the upper surface and the upper electrode portion can be increased, thereby improving the moisture resistance of the multilayer ceramic electronic component.

In the multilayer ceramic electronic components according to the fifth and sixth aspects of the present invention, the filler material may be glass containing one or more subcomponents selected from the group consisting of alkali metals, alkaline earth metals, transition metals, and boron.

The filler material is glass containing one or more secondary components selected from the group consisting of alkali metals, alkaline earth metals, transition metals, and boron, which makes it easier to plate a portion of the surface of the reinforced layer that covers the upper surface to form the upper electrode portion by plating.

In the multilayer ceramic electronic components according to the fifth and sixth aspects of the present invention, the surface of the upper electrode portion may be covered with at least one selected from Ni plating, Sn plating, Au plating, and Cu plating.

The multilayer ceramic electronic components according to the first to sixth aspects of the present invention may be capable of being embedded in a substrate.

The multilayer ceramic electronic components according to the first to sixth aspects of the present invention have upper electrode portions. Therefore, even if the multilayer ceramic electronic components are embedded in a substrate, they can be electrically connected via the upper electrode portions.

FIG. 1A is a vertical cross-sectional view of a multilayer ceramic capacitor according to one embodiment of the present invention. FIG. 1B is a vertical sectional view of a multilayer ceramic capacitor according to another embodiment of the present invention. FIG. 2A1 is a cross-sectional view of the multilayer ceramic capacitor taken along line IIA1-IIA1 shown in FIG. 1A. FIG. 2A2 is a cross-sectional view of the multilayer ceramic capacitor taken along line IIA2-IIA2 shown in FIG. 1A. FIG. 2B is a cross-sectional view of the multilayer ceramic capacitor taken along line IIB-IIB shown in FIG. 1B. FIG. 2C is a cross-sectional view of a modified example of the multilayer ceramic capacitor shown in FIG. 2B. FIG. 3 is a plan view of the multilayer ceramic capacitor shown in FIG. 1A. 4A to 4C are cross-sectional views of a main part showing a manufacturing process of the multilayer ceramic capacitor shown in FIG. 1A. FIG. 5 is a cross-sectional view of a main part showing an example of use of the multilayer ceramic capacitor shown in FIG. 1A. FIG. 6 is a cross-sectional view of a main part showing an example of use of the multilayer ceramic capacitor shown in FIG. 1A. FIG. 7A is a vertical cross-sectional view of a multilayer ceramic capacitor according to one embodiment of the present invention. FIG. 7B is a vertical cross-sectional view of a multilayer ceramic capacitor according to another embodiment of the present invention. FIG. 7C is a vertical cross-sectional view of a multilayer ceramic capacitor according to yet another embodiment of the present invention. FIG . 8A1 is a cross-sectional view of the multilayer ceramic capacitor taken along line XIIA1-XIIA1 shown in FIG. 7A . FIG . 8A2 is a cross-sectional view of the multilayer ceramic capacitor taken along line XIIA2-XIIA2 shown in FIG. 7A . FIG . 8A3 is an enlarged cross-sectional view of a portion of XIIA3 shown in FIG. 7A . FIG. 8B is a cross-sectional view of the multilayer ceramic capacitor taken along line XIIB-XIIB shown in FIG. 7B . FIG . 8C is a cross-sectional view of a modified example of the multilayer ceramic capacitor shown in FIG . 8B . FIG. 9 is a plan view of the multilayer ceramic capacitor shown in FIG. 7A . FIG. 10A is a cross-sectional view of a key portion showing a manufacturing process of the multilayer ceramic capacitor shown in FIG. 7A . Figure 10B is a cross-sectional view of a key part showing the manufacturing process continuing from Figure 10A . FIG. 11 is a cross-sectional view of a main part showing an example of use of the multilayer ceramic capacitor shown in FIG . 7A . FIG. 12 is a cross-sectional view of a main portion showing an example of use of the multilayer ceramic capacitor shown in FIG . 7A . FIG. 13A is a longitudinal cross-sectional view of a multilayer ceramic capacitor according to one embodiment of the present invention. FIG. 13B is a vertical cross-sectional view of a multilayer ceramic capacitor according to another embodiment of the present invention. FIG. 13C is a longitudinal cross-sectional view of a multilayer ceramic capacitor according to yet another embodiment of the present invention. FIG . 14A is a cross-sectional view of the multilayer ceramic capacitor taken along line XXIIA-XXIIA shown in FIG. 13A . FIG. 14B is a cross-sectional view of the multilayer ceramic capacitor taken along line XXIIB-XXIIB shown in FIG. 13B . FIG. 15 is a plan view of the multilayer ceramic capacitor shown in FIG. 13A . 16A to 16C are cross-sectional views of a main part showing a manufacturing process of the multilayer ceramic capacitor shown in FIG. 13A . FIG. 17 is a cross-sectional view of a main part showing an example of use of the multilayer ceramic capacitor shown in FIG. 13A . FIG. 18 is a cross-sectional view of a main part showing an example of use of the multilayer ceramic capacitor shown in FIG. 13A .

The present invention will now be described with reference to the embodiments shown in the drawings.

First Embodiment As an embodiment of the multilayer ceramic electronic component according to the present embodiment, a multilayer ceramic capacitor will be described.

As shown in FIG. 1A, the multilayer ceramic capacitor 2 according to this embodiment has an element body 4, a first terminal electrode 6, and a second terminal electrode 8. The element body 4 has an inner dielectric layer (insulating layer) 10 that is substantially parallel to a plane including the X-axis and the Y-axis, and an internal electrode layer 12, and the internal electrode layers 12 are alternately stacked between the inner dielectric layers 10 along the direction of the Z-axis. Here, "substantially parallel" means that most of the parts are parallel, but there may be some parts that are not parallel, and the internal electrode layers 12 and the inner dielectric layers 10 may be slightly uneven or tilted.

The portion where the inner dielectric layers 10 and the internal electrode layers 12 are alternately stacked is the interior region 13. The element body 4 also has exterior regions 11 on both end faces in the stacking direction Z (Z-axis). The exterior region 11 is formed by stacking a plurality of outer dielectric layers that are thicker than the inner dielectric layers 10 that constitute the interior region 13. The thickness of the interior region 13 in the Z-axis direction is preferably within the range of 10 to 75% of the total thickness z0 of the multilayer ceramic capacitor 2. The total thickness of the two exterior regions 11 is the total thickness z0 minus the thickness of the interior region 13, the thickness of the terminal electrodes 6 and 8, and the thickness of the upper surface reinforcement layer 16 described below.

In the following, the "inner dielectric layer 10" and the "outer dielectric layer" may be collectively referred to as the "dielectric layer."

The materials of the dielectric layers constituting the inner dielectric layer 10 and the exterior region 11 may be the same or different and are not particularly limited, and are composed mainly of a dielectric material having a perovskite structure, such as _ABO3 .

In ABO ₃ , A is, for example, at least one of Ca, Ba, Sr, etc., and B is at least one of Ti, Zr, etc. The molar ratio of A/B is not particularly limited and is 0.980 to 1.020. In addition, as a secondary component, oxides of rare earth elements (at least one selected from Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu), alkaline earth metals (Mg and Mn), transition metals (at least one selected from V, W, and Mo), or mixtures thereof, composite oxides, and sintering aids containing SiO ₂ as glass, etc. may be included.

One of the alternately stacked internal electrode layers 12 has a lead portion 12a electrically connected to the inside of the first terminal electrode 6 formed on the outside of the first end in the Y-axis direction of the element body 4. The other alternately stacked internal electrode layer 12 has a lead portion 12b electrically connected to the inside of the second terminal electrode 8 formed on the outside of the second end in the Y-axis direction of the element body 4.

In the figure, the X-axis, Y-axis, and Z-axis are mutually perpendicular, the Z-axis corresponds to the stacking direction of the inner dielectric layer 10 and the internal electrode layer 12, and the Y-axis corresponds to the direction in which the lead-out portions 12a and 12b are drawn out.

The interior region 13 has a capacitance region and an extraction region. The capacitance region is a region where the internal electrode layers 12 are stacked along the stacking direction with the inner dielectric layer 10 sandwiched therebetween. The extraction region is a region located between the extraction parts 12a (12b) of the internal electrode layers 12 that connect to the terminal electrodes 6 or 8. Furthermore, the side gap regions 14 shown in FIG. 2A1 and FIG. 2A2 are regions for protecting the internal electrode layers 12 located at both ends of the internal electrode layers 12 in the X-axis direction, and are generally made of a dielectric material similar to the inner dielectric layer 10 or the exterior region 11. However, the side gap region 14 may be made of a glass material or the like that becomes the end side covering layer 18b or the upper surface reinforcement layer 16 described later. The exterior region 11 may also be made of a glass material or the like.

The conductive material contained in the internal electrode layer 12 is not particularly limited, and metals such as Ni, Cu, Ag, Pd, Al, and Pt, or alloys thereof, can be used. As the Ni alloy, an alloy of Ni and one or more elements selected from Mn, Cr, Co, and Al is preferable, and the Ni content in the alloy is preferably 95 mass% or more. Note that Ni or the Ni alloy may contain various trace components such as P in an amount of about 0.1 mass% or less.

The material of the terminal electrodes 6, 8 is not particularly limited, but at least one of Ni, Pd, Ag, Au, Cu, Pt, Rh, Ru, Ir, etc., or an alloy thereof can be used. Usually, Cu, Cu alloy, Ni or Ni alloy, Ag, Ag-Pd alloy, In-Ga alloy, etc. are used.

In this embodiment, the terminal electrodes 6 and 8 are formed in close contact with the end faces 4a and 4b of the element body 4 in the Y-axis direction, and may be a single film or a multi-layer film. The terminal electrodes 6 and 8 in this embodiment have end electrode portions 6a and 8a that cover the end faces 4a and 4b, which are the draw-out ends of the element body 4 from which the lead portions 12a and 12b of the internal electrode layer 12 are drawn out. The terminal electrodes 6 and 8 also have upper electrode portions 6b and 8b that are formed contiguous to the end electrode portions 6a and 8a on a part of the upper surface 4c that is substantially perpendicular to the Z-axis of the element body 4.

Here, "substantially vertical" means that it is generally vertical, but may have some parts that are not vertical, and the upper electrode parts 6b, 8b may be slightly uneven or tilted.

Furthermore, as shown in FIG. 2A1, the terminal electrodes 6 and 8 each have a side electrode portion 6c, 8c formed continuously with the upper electrode portion 6b, 8b and the end electrode portion 6a, 8a (see FIG. 1A) on the side surfaces 4e, 4e opposite each other along the X-axis of the element body 4. As shown in FIG. 1A, the terminal electrodes 6 and 8 are insulated from each other by a predetermined distance in the Y-axis direction on the outer surface of the element body 4.

The thickness of each of the terminal electrodes 6 and 8 may be the same or different between the upper electrode portions 6b, 8b, the end electrode portions 6a, 8a, and the side electrode portions 6c, 8c, and is within the range of, for example, 2 to 15 μm. In this embodiment, the thickness of the upper electrode portions 6b, 8b and the side electrode portions 6c, 8c is greater than the thickness of the end electrode portions 6a, 8a by 100 to 750%.

In this embodiment, the terminal electrodes 6, 8 are not substantially formed on the lower surface 4d of the element body 4, which is located on the opposite side along the Z-axis direction to the upper surface 4c of the element body 4. In other words, the lower surface 4d of the element body 4 is not covered with the terminal electrodes 6, 8, and the entire lower surface 4d of the element body 4 is exposed to the outside. Moreover, the lower surface 4d is formed into a flat surface. Since the lower surface 4d is not covered with the terminal electrodes 6, 8, there are no stepped protrusions and it has excellent flatness.

In this embodiment, the outer surfaces of the end electrode portions 6a, 8a are covered with end coating layers 18b, 18b. This improves the moisture resistance of the multilayer ceramic capacitor 2. In other words, even if the terminal electrodes 6, 8 are thinned due to the low profile of the multilayer ceramic capacitor 2, it is possible to prevent moisture from entering the inside of the multilayer ceramic capacitor 2. As a result, even if the multilayer ceramic capacitor 2 is used in a moist or humid environment, or if the manufacturing process for the multilayer ceramic capacitor 2 includes a process using water or a wet process, it is possible to prevent moisture from entering the inside of the multilayer ceramic capacitor 2 and suppress a decrease in insulation.

In addition, the outer surfaces of the end electrode portions 6a, 8a of the multilayer ceramic capacitor 2 of this embodiment are covered with end coating layers 18b, 18b, which increases the strength.

In this embodiment, the coverage rate of the end coating layer 18b, which is expressed by (coverage area of the end coating layers 18b, 18b/area of the outer surfaces of the end electrode portions 6a, 8a) x 100, is preferably 96 to 100%. This can further increase the moisture resistance of the multilayer ceramic capacitor 2 and can further increase its strength. From the above viewpoint, it is more preferable that the coverage rate of the end coating layer 18b is 98 to 100%.

In this embodiment, the relative thickness of the end coating layer 18b, expressed as (average thickness of the end coating layers 18b, 18b/average thickness of the end electrode portions 6a, 8a) x 100, is preferably 20 to 500%. This makes it possible to further improve the moisture resistance of the multilayer ceramic capacitor 2, increase its strength, and prevent the dimension of the multilayer ceramic capacitor 2 in the Y-axis direction from becoming too large, allowing for problem-free mounting.

The material of the end side coating layer 18b is not particularly limited, and examples include glass, alumina-based composite material, zirconia-based composite material, polyimide resin, epoxy resin, aramid fiber, fiber-reinforced plastic, etc., but it is preferable that the film is mainly composed of glass or resin whose main component is Si. This can further improve the moisture resistance of the multilayer ceramic capacitor 2 and increase its strength.

From the above viewpoint, examples of glasses containing Si as a main component include Si-B-Zn-O type glasses and Si-Al-M-O type glasses (M is an alkaline earth metal), and other glass components may include BaO and alkali metals.

The Si-B-Zn-O glass of the present embodiment preferably contains 30 to 70 mass % of _SiO2 , 1 to 20 mass % of _B2O3 , and 1 to 60 mass % of ZnO in the glass components, which can further increase the moisture resistance of the multilayer ceramic capacitor 2 and increase _its strength.

In addition, the Si-B-Zn-O glass of the present embodiment preferably contains 70 to 100 mass % of SiO ₂ , B ₂ O ₃ , and ZnO in total in the glass components, which can further increase the moisture resistance of the multilayer ceramic capacitor 2 and increase its strength.

The Si-Al-M-O glass of this embodiment preferably contains ₃₀ to 70 mass % of _SiO2 , 2 to 20 mass % of _Al2O3 , and 5 to 20 mass % of MO in the glass components. This can further improve the moisture resistance and strength of the multilayer ceramic capacitor 2. Note that M is preferably Ca or Sr.

In addition, the Si-Al-MO glass of the present embodiment preferably contains 70 to 100 mass % of _SiO2 , _{Al2O3 ,} and MO in total in the glass component, which can further improve the moisture resistance of the multilayer ceramic capacitor 2 and increase its strength.

In this embodiment, the end side covering layer 18b can be made of glass with a softening point of 600°C or more and 850°C or less. This improves adhesion to the end side electrode parts 6a, 8a, increases moisture resistance, and improves bending strength. From the above perspective, it is more preferable that the softening point of the glass used for the end side covering layer 18b is 600°C or more and 850°C or less.

In addition, in this embodiment, the end side coating layer 18b is preferably made of a material with a lower elastic modulus than the dielectric layer. This reduces external stress impacts and suppresses cracks and breakage in later processes.

Furthermore, in this embodiment, the end side coating layer 18b is preferably made of a material that has a lower linear thermal expansion coefficient than the dielectric layer. This makes it possible to improve strength by adjusting stress using the difference in linear expansion coefficients.

In this embodiment, the upper surface coating layer 18 covering the upper surface 4c of the element body 4 located between the pair of upper electrode portions 6b, 8b is in close contact with the surfaces of the upper electrode portions 6b, 8b so as to be substantially flush with them.

Here, "substantially flush" means that the surface is generally flush, but may have some steps; for example, the relative thickness of the upper surface coating layer 18 calculated from the formula (average thickness of the upper surface coating layer 18/average thickness of the upper electrode portions 6b, 8b) x 100 may be 70-110%. This reduces the steps on the upper surface 4c side of the element body 4, suppresses stress concentration at the steps even when the multilayer ceramic capacitor 2 is made low-profile, and increases the bending strength of the multilayer ceramic capacitor 2. In addition, the multilayer ceramic capacitor 2 can be easily picked up by vacuum suction.

The material of the upper surface coating layer 18 is not particularly limited, and examples include glass, alumina-based composite material, zirconia-based composite material, polyimide resin, epoxy resin, aramid fiber, fiber-reinforced plastic, etc., but from the viewpoint of increasing adhesion with the exterior region 11 and the upper electrode parts 6b, 8b and improving bending strength, glass with a softening point of 600°C or more and 850°C or less is preferable.

From the above viewpoints, it is more preferable that the softening point of the glass used for the upper surface coating layer 18 is 600° C. or more and 850° C. or less. Examples of such glass include Si-B-Zn-O type glass and Si-Ba-Al-O type glass, and other glass components may include BaO, Al ₂ O ₃ , alkali metals, CaO, and SrO.

The glass component constituting the upper surface coating layer 18 preferably contains 30 to 70 mass % of _SiO2 , 1 to 20 mass % of _B2O3 , and 1 to 60 mass % of ZnO in the _glass component, which makes it easier to set the softening point of the glass within an appropriate range.

In addition, it is preferable that the glass component constituting the upper surface coating layer 18 of this embodiment contains 70 to 100 mass % of SiO ₂ , B ₂ O ₃ and ZnO in total, which makes it easier to set the softening point of the glass in an appropriate range.

In addition, like the end-side coating layer 18b, the upper surface coating layer 18 is preferably made of a material with a lower elastic modulus than the dielectric layer. This helps to mitigate external stress impacts and suppresses cracks and breakage in later processes.

Furthermore, like the end-side coating layer 18b, the upper surface coating layer 18 is preferably made of a material having a lower linear thermal expansion coefficient than the dielectric layer. This makes it possible to improve strength by adjusting stress using the difference in linear expansion coefficients.

The materials of the end side coating layer 18b and the top surface coating layer 18 may be the same or different. However, as described above, the material of the end side coating layer 18b is selected with an emphasis on improving moisture resistance, whereas the material of the top surface coating layer 18 is selected with an emphasis on adhesion to the upper electrode parts 6b, 8b and the exterior region 11 from the viewpoint of reducing the step on the top surface 4c side. From this viewpoint, it is preferable that the materials of the end side coating layer 18b and the top surface coating layer 18 are different.

When the end covering layer 18b and the top covering layer 18 are made of different materials, it is preferable that their properties are not significantly different from each other. Specifically, when the end covering layer 18b and the top covering layer 18 are both made of films mainly composed of resin, it is preferable that the difference in elastic modulus between the end covering layer 18b and the top covering layer 18 is 20×10 ⁻⁶ Pa or less. When the end covering layer 18b and the top covering layer 18 are both made of glass mainly composed of Si, it is preferable that the difference in thermal expansion coefficient between the end covering layer 18b and the top covering layer 18 is 20×10 ⁻⁶ /K or less. This makes it easier to manufacture the multilayer ceramic capacitor 2, and makes it less likely that defects will occur in the multilayer ceramic capacitor 2.

The shape and size of the multilayer ceramic capacitor 2 may be determined appropriately depending on the purpose and application, but in this embodiment, the total thickness z0 of the multilayer ceramic capacitor 2 in the Z-axis direction can be reduced to, for example, 100 μm or less, preferably 90 μm or less, more preferably 80 μm or less, and particularly preferably 60 μm or less, which contributes to a low profile of the multilayer ceramic capacitor 2.

In this embodiment, the length y0 in the Y-axis direction, which is the longitudinal length of the capacitor 2, can be set to three times or more the thickness z0, preferably 300 μm or more, and preferably 400 to 1200 μm. The width x0 in the X-axis direction of the capacitor 2 can be set to two times or more the thickness z0, preferably 200 μm or more, and preferably 200 to 600 μm.

In the multilayer ceramic capacitor according to this embodiment, the lower surface 4d of the element body 4 is a flat surface, which makes it easier to embed the multilayer ceramic capacitor 2 inside the multilayer substrate 40, as shown in FIG. 5, for example. In FIG. 5, the wiring pattern 42 formed on the multilayer substrate 40 is connected to the upper electrode portions 6b, 8b of the terminal electrodes 6, 8 of the multilayer ceramic capacitor 2 via through-hole electrodes or the like. In this embodiment, when the flat surface that is the lower surface 4d of the element body 4 is placed on the mounting surface, the element body 4 is attached in close contact with the mounting surface, improving the bending strength of the multilayer ceramic capacitor 2.

In addition, in this embodiment, the exterior region 11 constituting the upper surface 4c or the lower surface 4d of the element body 4 may be made of a dielectric material having a higher strength than the inner dielectric layer 10. This configuration further improves the bending strength of the multilayer ceramic capacitor 2. Furthermore, improved strength makes it easier to lengthen the longitudinal dimension y0 or width dimension x0 of the element body 4, increasing the opposing area between the internal electrode layers 12 inside the element body 4, and improving characteristics such as capacitance. Furthermore, the side gap region 14 shown in Figures 2A1 and 2A2 may also be made of a dielectric material having a higher strength than the inner dielectric layer 10.

Next, we will explain in detail the manufacturing method of the multilayer ceramic capacitor 2 as one embodiment of the present invention.

First, to manufacture the inner green sheet that will form the inner dielectric layer 10 shown in FIG. 1A after firing, and the outer green sheet that will form the exterior region 11, a paste for the inner green sheet and a paste for the outer green sheet are prepared. The paste for the inner green sheet and the paste for the outer green sheet are usually composed of an organic solvent-based paste obtained by kneading ceramic powder with an organic vehicle, or a water-based paste.

The raw material for the ceramic powder can be appropriately selected from composite oxides and various compounds that become oxides, such as carbonates, nitrates, hydroxides, and organometallic compounds, and can be mixed and used. In this embodiment, the raw material for the ceramic powder is used as a powder with an average particle size of 0.45 μm or less, preferably about 0.1 to 0.3 μm. In order to make the inner green sheet extremely thin, it is desirable to use a powder that is finer than the thickness of the green sheet.

An organic vehicle is a binder dissolved in an organic solvent. There are no particular limitations on the binder used in the organic vehicle, and it may be appropriately selected from various common binders such as ethyl cellulose and polyvinyl butyral. There are also no particular limitations on the organic solvent used, and it may be appropriately selected from various organic solvents such as acetone and methyl ethyl ketone.

The green sheet paste may also contain additives selected from various dispersants, plasticizers, dielectrics, minor component compounds, glass frits, insulators, etc., as necessary.

Examples of plasticizers include phthalates such as dioctyl phthalate and benzyl butyl phthalate, adipic acid, phosphate esters, and glycols.

Next, to manufacture the internal electrode pattern layer that will constitute the internal electrode layer 12 shown in FIG. 1A after firing, a paste for the internal electrode layer is prepared. The paste for the internal electrode layer is prepared by kneading the conductive material made of the various conductive metals and alloys described above with the organic vehicle described above.

The terminal electrode paste, which will form the terminal electrodes 6 and 8 shown in FIG. 1A after firing, may be prepared in the same manner as the internal electrode layer paste described above.

The inner green sheets and the internal electrode layer paste prepared above are used to alternately stack the inner green sheets and the internal electrode pattern layers to produce an inner laminate. After the inner laminate is produced, the outer green sheets are formed using the outer green sheet paste, and pressed in the stacking direction to obtain a green laminate.

In addition to the above, the green laminate may be produced by laminating a predetermined number of inner green sheets and internal electrode pattern layers alternately directly onto an outer green sheet, and then applying pressure in the lamination direction to obtain the green laminate.

Specifically, first, an inner green sheet is formed on a carrier sheet (e.g., a PET film) as a support by a doctor blade method or the like. After being formed on the carrier sheet, the inner green sheet is dried.

Next, an internal electrode pattern layer is formed on the surface of the internal green sheet using an internal electrode layer paste, to obtain an internal green sheet having an internal electrode pattern layer. Next, multiple internal green sheets having internal electrode pattern layers are stacked to produce an internal laminate, and then an appropriate number of external green sheets are formed above and below the internal laminate using an external green sheet paste, and pressed in the stacking direction to obtain a green laminate.

Next, the green laminate is cut into individual pieces to obtain green chips. The method for forming the internal electrode pattern layer is not particularly limited, and it may be formed by a printing method, a transfer method, or a thin film formation method such as vapor deposition or sputtering.

The green chip is solidified by removing the plasticizer through solidification and drying. After solidification and drying, the green chip is subjected to a binder removal process, a firing process, and an annealing process as required to obtain the element body 4. The binder removal process, firing process, and annealing process may be performed consecutively or independently.

Next, terminal electrode paste is applied to both end faces in the Y-axis direction of the element body 4 and fired to form the terminal electrodes 6, 8. When forming the terminal electrodes 6, 8, for example, as shown in FIG. 4, a dummy block 20 is temporarily bonded between the lower surfaces 4d, 4d of the two element bodies 4, 4 to first form a workpiece 22 by integrating them.

The dummy block 20 is preferably made of a material that can be removed in a later process, and is preferably a material to which the terminal electrode paste does not easily adhere. The dummy block 20 is made of, for example, silicone rubber, nitrile rubber, polyurethane, fluororesin, PET resin, PEN resin, etc. The width in the X-axis direction and the width in the Y-axis direction of the dummy block 20 are preferably approximately the same as the size of the element body 4. The thickness in the Z-axis direction of the dummy block 20 may be equal to the thickness in the Z-axis direction of the element body 4, or may be thinner or thicker than that.

In addition, the workpiece 22 may be formed by directly bonding the lower surfaces 4d, 4d of the two element bodies 4, 4 with a peelable adhesive in a later process without providing the dummy block 20. Preferred adhesives include modified silicone polymer, PVA aqueous solution glue, water-soluble acrylic resin aqueous solution glue, modified polyurethane, a two-liquid type of modified silicone + epoxy resin, and starch glue. Also, instead of the dummy block 20, one or more element bodies 4 may be bonded between the two element bodies 4, 4 to form the workpiece 22.

Because the workpiece 22 is a combination of two or more element bodies 4, 4, even if the element bodies 4, 4 themselves are thin in the Z-axis direction, it has a thickness that is easy to handle, and the terminal electrodes 6 and 8 can be formed by attaching the workpiece 22 to the through holes 32 of the holding plate 30 in the same manner as in the past. The method of forming the terminal electrodes 6, 8 is not particularly limited, and any appropriate method such as application and baking of terminal electrode paste, plating, vapor deposition, sputtering, etc. can be used. If necessary, a coating layer is formed on the surfaces of the terminal electrodes 6, 8 by plating or the like. Examples of coating layers include Ni plating, Sn plating, Au plating, and Cu plating.

After the terminal electrodes 6 and 8 are formed, the two element bodies 4, 4 are separated by, for example, removing the dummy block 20, to obtain the multilayer ceramic electronic component 2 shown in FIG. 1A. In other words, the terminal electrodes 6, 8 are substantially not formed on the lower surface 4d of the element body 4, and a multilayer ceramic capacitor 2 is obtained in which the entire lower surface 4d of the element body 4 is exposed to the outside.

Next, an end side coating layer 18b is formed on the outer surfaces of the end side electrodes 6a, 8a of the terminal electrodes 6, 8, and an upper surface coating layer 18 is formed on the upper surface 4c perpendicular to the Z axis of the element body 4. The method for forming the upper surface coating layer 18 and the end side coating layer 18b is not particularly limited, and examples thereof include dipping, printing, coating, vapor deposition, sputtering, etc.

For example, when the top covering layer 18 and the end covering layer 18b are formed by coating, a coating layer paste is applied to the outer surfaces of the end electrode portions 6a, 8a and baked to form the end covering layer 18b, and then the coating layer paste is applied to the top surface 4c of the element body 4 and baked to form the top covering layer 18. The baking conditions for the element body 4 to which the coating layer paste is applied are not particularly limited, and both the top covering layer 18 and the end covering layer 18b are baked, for example, at 600 to 1000°C in a humidified _N2 or dry _N2 atmosphere, for 0.1 to 3 hours.

Next, the surfaces of the upper electrodes 6b and 8b, the surface of the top coating layer 18, and the ends of the end coating layer 18b in the Z-axis direction are polished to be flush with each other. If a plating film is formed on the surfaces of the upper electrodes 6b and 8b, the plating film and the surface of the top coating layer 18 may be polished to be flush with each other.

The multilayer ceramic capacitor 2 of this embodiment manufactured in this manner is mounted on a printed circuit board by soldering or the like and used in various electronic devices. Alternatively, as shown in FIG. 5, the multilayer ceramic capacitor 2 is embedded inside a multilayer substrate 40 for use. Specific applications of the multilayer ceramic capacitor 2 of this embodiment include, but are not limited to, a decoupling capacitor, and the capacitor can also be used as a high-voltage capacitor, a low ESL capacitor, a large-capacity capacitor, etc.

In the multilayer ceramic capacitor 2 of this embodiment, the element body 4 is separated after the terminal electrodes 6, 8 are formed, resulting in a multilayer ceramic capacitor 2 that is, for example, half or less the thickness of a conventional one.

In the resulting multilayer ceramic capacitor 2, the terminal electrodes 6, 8 are not substantially formed on the lower surface 4d of the element body 4, or the entire lower surface 4d of the element body 4 is exposed. The total thickness z0 of the multilayer ceramic capacitor 2 can be reduced to 100 μm or less, preferably 90 μm or less, more preferably 80 μm or less, and particularly preferably 60 μm or less. In other words, this contributes to reducing the height of the multilayer ceramic capacitor 2.

In addition, in this embodiment, the lower surface 4d of the element body 4 is a flat surface. By having the lower surface 4d of the element body 4 as a flat surface, it becomes easier to embed the multilayer ceramic capacitor 2 inside the multilayer substrate 40, for example as shown in FIG. 5. In addition, when the flat surface, which is the lower surface 4d of the element body 4, is placed on the mounting surface, the element body 4 is attached in close contact with the mounting surface, improving the bending strength of the multilayer ceramic capacitor 2.

Second embodiment

As shown in FIG. 2A2, the multilayer ceramic capacitor 2 according to this embodiment is similar to the multilayer ceramic capacitor 2 according to the first embodiment, except as described below. In this multilayer ceramic capacitor 2, the side surface 4e of the element body 4 that faces along the X-axis direction has a side coating layer 18a that is continuous with the top surface coating layer 18 of the first embodiment. By configuring it in this way, the strength of the multilayer ceramic capacitor 2 is further improved.

The material of the side coating layer 18a is not particularly limited, and may be the same as or different from the top coating layer 18. The thickness of the side coating layer 18a is also not particularly limited, and may be the same as or different from the top coating layer 18.

The method for forming the side coating layer 18a is not particularly limited, and it may be formed, for example, by a method similar to that for the top coating layer 18.

Third embodiment

As shown in Figures 1B and 2B, the multilayer ceramic capacitor 2a according to this embodiment is similar to the multilayer ceramic capacitor 2 according to the first embodiment, except as described below. In this multilayer ceramic capacitor 2a, the upper surface 4c (or the lower surface 4d) of the element body 4 includes an upper surface reinforcement layer 16 made of a material having a higher strength than the inner dielectric layer 10.

The upper surface reinforcement layer 16 is formed on the upper surface 4c of the element body 4 after the element body 4 is formed in the same manner as in the first embodiment, and before the terminal electrodes 6 and 8 are formed. The material of the upper surface reinforcement layer 16 is not particularly limited, but examples thereof include glass, alumina-based composite material, zirconia-based composite material, polyimide resin, epoxy resin, aramid fiber, and fiber-reinforced plastic. The material of the upper surface reinforcement layer 16 may be the same as or different from the material of the upper surface coating layer 18.

This configuration further improves the bending strength of the multilayer ceramic capacitor 2a. In addition, the improved strength makes it easier to increase the longitudinal dimension y0 (see FIG. 1A) or width dimension x0 (see FIG. 2A1 and FIG. 2A2) of the element body 4 even if the element body 4 is made thinner, and the opposing area between the internal electrode layers 12 inside the element body 4 is increased, further improving the characteristics of the multilayer ceramic capacitor 2a, such as the capacitance.

From the above viewpoints, it is preferable that the relative thickness of the upper surface reinforcement layer 16, calculated from the formula (average thickness of the upper surface reinforcement layer 16/average thickness of the upper electrode parts 6b, 8b) x 100, is 20 to 133%.

The glass components constituting the upper surface reinforced layer 16 are not particularly limited. It is more preferable that the glass contained in the upper surface reinforced layer 16 of this embodiment has at least one of Si and Al as its main component. The main component is a component contained in the glass at 30% to 70% by mass. It is even more preferable that the glass contained in the upper surface reinforced layer 16 of this embodiment has Si and Al as its main components.

The glass contained in the upper surface reinforced layer 16 of this embodiment preferably contains 30% to 70% by mass of SiO _2. When the SiO ₂ content is within the above range, the amount of network-forming oxide is sufficient, and plating resistance is improved, compared with when the SiO 2 content is less than the above range. When the SiO ₂ content is within the above range, the softening point is prevented from becoming too high, and the working temperature is prevented from becoming too high, compared with when the SiO 2 content is greater than the above range.

The glass contained in the upper surface reinforced layer 16 of this embodiment preferably contains 1 mass % to 15 mass % of Al ₂ O _3. When the Al ₂ O ₃ content is within the above range, the plating resistance is better than when the content is less than the above range. When the Al ₂ O ₃ content is within the above range, the softening point is prevented from rising too much, compared to when the content is more than the above range.

The glass contained in the upper surface reinforcement layer 16 of this embodiment preferably contains one or more subcomponents selected from the group consisting of alkali metals, alkaline earth metals, transition metals, and boron.

The glass contained in the upper surface reinforcement layer 16 of this embodiment is glass containing one or more sub-components selected from the group consisting of alkali metals, alkaline earth metals, transition metals, and boron, which makes it easier to plate when forming the upper electrode portions 6b and 8b by plating on a portion of the surface of the upper surface reinforcement layer 16 that covers the upper surface 4c.

The glass contained in the upper surface reinforcement layer 16 of this embodiment contains alkali metals, transition metals, and boron, which can lower the softening point of the glass.

The glass contained in the upper surface reinforced layer 16 of this embodiment contains an alkali metal, which improves plating resistance. The alkali metal used in this embodiment is not particularly limited. Examples of the alkali metal used in this embodiment include Li, Na, and K. The alkali metal may be used alone or in combination of two or more. When the glass contained in the upper surface reinforced layer 16 of this embodiment contains Li, the glass can be densely baked, making it less likely to crack. When the glass contained in the upper surface reinforced layer 16 of this embodiment contains Na or K, the thermal expansion coefficient becomes high, making it less likely to crack.

In this embodiment, the glass contained in the upper surface reinforcement layer 16 preferably contains 0.1% to 15% by mass of alkali metal.

In the present embodiment, the glass contained in the upper surface reinforcement layer 16 contains an alkaline earth metal, which improves the adhesion between the glass contained in the upper surface reinforcement layer 16 and the dielectric layer, making delamination less likely to occur. In addition, the thermal expansion coefficient is prevented from becoming too small, making it difficult for cracks to occur. Furthermore, when the alkaline earth metal is Ba and the dielectric layer is _BaTiO3 , Ba is prevented from dissolving into the glass component, suppressing a decrease in HALT reliability. When BaO is contained within the above range, vitrification is improved and plating resistance is also improved compared to when it is contained more than the above range.

The alkaline earth metal constituting the glass contained in the upper surface reinforcement layer 16 of this embodiment is not particularly limited. Examples of alkaline earth metals used in this embodiment include Mg, Ba, Ca, and Sr. One type of alkaline earth metal may be used alone, or two or more types may be used in combination. In this embodiment, it is preferable to use Ba or Ca as the alkaline earth metal.

In this embodiment, the glass contained in the upper surface reinforced layer 16 preferably contains 20% to 60% by mass of BaO.

The glass contained in the upper surface reinforcement layer 16 of this embodiment preferably contains 70 mass % to 100 mass % of SiO ₂ , BaO, and Al ₂ O ₃ in total. This makes it easier for a Ba-Ti-Si-O phase to form at the interface between the dielectric layer and the upper surface reinforcement layer 16.

In this embodiment, the glass contained in the upper surface reinforced layer 16 preferably contains 0% to 15% by mass of CaO. This increases the thermal expansion coefficient.

The glass contained in the upper surface reinforcement layer 16 of this embodiment preferably contains 0% to 20% by mass of SrO, which can increase the thermal expansion coefficient, and when SrO is contained within the above range, it is possible to prevent SrO from reacting with _BaTiO3 and improve the insulation properties and reliability of the chip compared to when the SrO content is greater than the above range.

The transition metal used in the glass contained in the upper surface reinforcement layer 16 of this embodiment is not particularly limited. Examples of transition metals used in the upper surface reinforcement layer 16 of this embodiment include V, Zn, W, and Mo. The transition metal used in the upper surface reinforcement layer 16 of this embodiment is preferably V or Zn. This makes it easier to form plating as the upper electrode portions 6b and 8b. The transition metals according to this embodiment may be used alone or in combination of two or more types.

In this embodiment, the glass contained in the upper surface reinforcement layer 16 preferably contains 0% to 20% by mass of transition metals.

The glass contained in the upper surface reinforced layer 16 of this embodiment preferably contains 0 mass % to 10 mass % of B _{2 O 3. This allows the glass to exert its effect as a network-forming oxide. When B 2 O 3 is} contained within the above range, plating resistance can be improved compared to when the content is greater than the above range.

In this embodiment, the upper surface reinforcement layer 16 constitutes only a portion of the outer surface side of the exterior region 11, but it may occupy most or all of the exterior region 11. The upper surface reinforcement layer 16 can be formed by applying a reinforcement layer paste to the upper surface 4c or the lower surface 4d of the element body 4 and baking it.

This reinforcing layer paste is obtained, for example, by kneading the above-mentioned glass raw material, a binder mainly composed of ethyl cellulose, and terpineol and acetone as dispersion media in a mixer. There are no particular limitations on the method of applying the reinforcing layer paste to the element body 4, and examples of the method include dipping, printing, coating, vapor deposition, spraying, etc.

The conditions for baking the element body 4 coated with the reinforcing layer paste are not particularly limited, and for example, the element body 4 is baked in a humidified _N2 or dry _N2 atmosphere at 700°C to 1300°C for 0.1 to 3 hours.

Fourth embodiment

As shown in FIG. 2C, the multilayer ceramic capacitor 2b according to this embodiment is the same as the multilayer ceramic capacitor 2a according to the third embodiment, except as described below. In this multilayer ceramic capacitor 2b, the side surfaces 4e facing each other along the X-axis direction of the element body 4 have side reinforcement layers 16a that are continuous with the upper surface reinforcement layer 16 of the third embodiment. By configuring in this way, the strength of the multilayer ceramic capacitor 2 is further improved.

In FIG. 2C, the side reinforcement layer 16a constitutes only a portion of the side surface 4e of the side gap region 14, but it may occupy the entire side gap region 14. In other words, the side reinforcement layer 16a may be in contact with the end of the internal electrode layer 12 in the X-axis direction.

The material of the side reinforcement layer 16a is not particularly limited, and may be the same as or different from the upper surface reinforcement layer 16. The thickness of the side reinforcement layer 16a is also not particularly limited, and may be the same as or different from the upper surface reinforcement layer 16.

The method for forming the side reinforcement layer 16a is not particularly limited, and it may be formed, for example, by the same method as the top reinforcement layer 16.

11th embodiment As shown in Fig. 7A , the multilayer ceramic capacitor 2 according to this embodiment is similar to the multilayer ceramic capacitor 2 according to the first embodiment, except as described below. In this embodiment, as shown in Fig . 7A , a conductive metal film 5 is interposed at each interface between the element body 4 and the terminal electrodes 6, 8. Each conductive metal film 5 has an upper metal film portion formed on the upper surface 4c of the element body 4 corresponding to the terminal electrodes 6, 8, an end metal film portion formed on the end surfaces 4a, 4b of the element body 4, and a side metal film portion formed on the side surface 4e of the element body 4 as shown in Fig. 8A1 . In each conductive metal film 5, the upper metal film portion, the end metal film portion, and the side metal film portion are formed continuously.

As shown in Fig . 7A , on the upper surface of the element body 4, the inner ends 5a of the pair of conductive metal films 5 along the Y-axis direction preferably protrude by a predetermined length toward the center of the element body 4 in the Y-axis direction beyond the inner ends of the upper electrode portions 6b, 8b of the respective terminal electrodes 6, 8. The predetermined length by which the inner ends 5a protrude is not particularly limited, but is preferably 0 to 30 µm. However, the predetermined length for the protrusion is determined so that the inner ends 5a of both metal films 5 are not electrically connected to each other and short-circuited.

The conductive metal film contains at least one of the following metals: Pt, Rh, Ru, Re, Ir, and Pd. By forming a conductive metal film using such a metal on the surface of the element body, the adhesion between the terminal electrode and the surface of the element body can be further improved.

As shown in Figure 8A3 , the surface of the element body 4 is the surface of a sintered ceramic body, and when observed microscopically, it is found to have irregularities consisting of repeated concave and convex portions. The irregularities formed on the surface of the element body 4 have a surface roughness in the range of 2 to 4 μm as expressed in JIS B 0601, for example.

In this embodiment, the coverage area ratio of the uneven surface formed on the surface of the element body 4 covered by the conductive metal film 5 is preferably within the range of 20 to 70%, and more preferably 50 to 70%. If the coverage area ratio of the surface of the element body 4 covered by the conductive metal film 5 is too small or too large, the effect of improving the adhesion between the terminal electrodes 6, 8 and the element body 4 is small, and if the coverage area ratio is within a specific range, the effect of improving the adhesion is large.

From this viewpoint, the thickness t of the conductive metal film 5 is preferably smaller than the size of the irregularities formed on the surface of the element body 4 (the Z-axis distance between adjacent convex and concave portions), and is not particularly limited, but is preferably about 100 to 500 nm. Furthermore, the conductive metal film 5 is preferably a thin metal film formed by a thin film method such as sputtering, ion plating, plasma CVD, thermal CVD, molecular beam epitaxy, or spin coating. The terminal electrodes 6 and 8 are formed on the surface of the conductive metal film 5.

In addition, FIG . 8A3 illustrates the conductive metal film 5 and the terminal electrodes 6, 8 formed on the upper surface 4c of the element body 4, but the same applies to the conductive metal film 5 and the terminal electrodes 6, 8 formed on the end faces 4a, 4b of the element body 4 shown in FIG. 7A and the side surface 4e shown in FIG. 8A1 .

In the multilayer ceramic capacitor 2 of this embodiment, a conductive metal film 5 is interposed at the interface between the element body 4 and the terminal electrodes 6, 8. This configuration can increase the adhesion between the terminal electrodes 6, 8 and the surface of the element body 4. As a result, improved adhesion between the terminal electrodes 6, 8 and the element body 4 is achieved, and moisture resistance can be improved.

In this embodiment, the coverage area ratio of the metal film 5 can be defined as the area ratio of the metal film 5 filling the concaves of the uneven surface of the element body 4. This coverage area ratio is measured, for example, by polishing the surfaces of the terminal electrodes 6, 8 in the cross section of the element body 4 shown in Fig . 8A3 , and observing the surface of the element body 4 at a position in the Z-axis direction where the terminal electrodes 6, 8 are completely removed, using an SEM photograph viewed from the Z-axis direction. For example, the area ratio is obtained by measuring the area occupied by the metal film 5 within a surface observation photograph of 50 μm × 50 μm. For example, the coverage area ratio of the metal film 5 is obtained by averaging five surface observation photographs at different X-Y positions.

In addition, in this embodiment, the terminal electrodes 6, 8 are not substantially formed on the lower surface 4d of the element body 4, which is located on the opposite side along the Z-axis direction to the upper surface 4c of the element body 4. In other words, the lower surface 4d of the element body 4 is not covered with the terminal electrodes 6, 8, and the entire lower surface 4d of the element body 4 is exposed to the outside. Moreover, the lower surface 4d is formed into a flat surface. Since the lower surface 4d is not covered with the terminal electrodes 6, 8, there are no stepped convex portions, and it has excellent flatness.

Furthermore, in this embodiment, the outer surfaces of the end electrode portions 6a, 8a are covered with end coating layers 18b, 18b. This further improves the moisture resistance of the multilayer ceramic capacitor 2. That is, even if the terminal electrodes 6, 8 become thinner due to the lower height of the multilayer ceramic capacitor 2, it is possible to prevent moisture from entering the inside of the multilayer ceramic capacitor 2. As a result, even if the multilayer ceramic capacitor 2 is used in a moist or humid environment, or even if the manufacturing process for the multilayer ceramic capacitor 2 includes a process using water or a wet process, it is possible to prevent moisture from entering the inside of the multilayer ceramic capacitor 2 and suppress a decrease in insulation.

In addition, the strength of the multilayer ceramic capacitor 2 of this embodiment can be increased because the outer surfaces of the end electrode portions 6a and 8a are covered with end coating layers 18b. The end coating layers 18b of this embodiment are the same as the end coating layers 18b of the first embodiment.

In this embodiment, the upper surface coating layer 18 covering the upper surface 4c of the element body 4 located between the pair of upper electrode portions 6b, 8b is in close contact with and substantially flush with the surfaces of the upper electrode portions 6b, 8b. The upper surface coating layer 18 covers the upper surface 4c of the element body 4, and also covers the surfaces of the inner ends 5a of the conductive metal films 5 that protrude from the inner ends of the terminal electrodes 6, 8. The upper surface coating layer 18 of this embodiment is similar to the upper surface coating layer 18 of the first embodiment.

Next, we will explain in detail the manufacturing method of the multilayer ceramic capacitor 2 as one embodiment of the present invention.

First, the element body 4 is obtained in the same manner as in the first embodiment. Next, the green laminate is cut into individual pieces to obtain green chips. The method for forming the internal electrode pattern layer is not particularly limited, and it may be formed by a printing method, a transfer method, or a thin film formation method such as deposition or sputtering.

The green chip is solidified by removing the plasticizer through solidification and drying. After solidification and drying, the green chip is subjected to a binder removal process, a firing process, and an annealing process as required to obtain the element body 4. The binder removal process, firing process, and annealing process may be performed consecutively or independently.

10A , a resist film 60 is formed in a predetermined pattern on the center of the Y-axis direction of the upper surface 4c of the element body 4, the element body 4 is fixed on a mounting table 62 of a sputtering device, and a conductive metal film 5 is formed by sputtering. The conductive metal film 5 is not formed on the surface of the element body 4 whose upper and side surfaces are covered with the resist film 60. In addition, since the lower surface 4d of the element body 4 is in contact with the surface of the mounting table 62, the metal film 5 is not formed on the lower surface 4d. The formation of the resist film 60 and the conductive metal film 5 may be performed before cutting the green laminate.

Next, the resist film 60 is removed, and a terminal electrode paste is applied to both end faces (surfaces of the conductive metal films 5) in the Y-axis direction of the element body 4 on which the pair of conductive metal films 5 are formed, and then fired to form the terminal electrodes 6, 8. When forming the terminal electrodes 6, 8, for example, as shown in Fig. 10B , a dummy block 20 is temporarily bonded between the lower surfaces 4d, 4d of the two element bodies 4, 4 to first form a workpiece 22 by integrating these together.

Since the workpiece 22 is a combination of two or more element bodies 4, 4, even if the element bodies 4, 4 themselves are thin in the Z-axis direction, they have a thickness that is easy to handle, and the workpiece 22 can be attached to the through hole 32 of the holding plate 30 in the same manner as in the conventional method, and the terminal electrodes 6 and 8 can be formed.

After the terminal electrodes 6 and 8 are formed, the two element bodies 4, 4 are separated by, for example, removing the dummy block 20, thereby obtaining the multilayer ceramic electronic component 2 shown in Fig . 7A . In other words, the terminal electrodes 6, 8 are substantially not formed on the lower surface 4d of the element body 4, and the multilayer ceramic capacitor 2 in which the entire lower surface 4d of the element body 4 is exposed to the outside is obtained.

Next, an end-side coating layer 18b is formed on the outer surfaces of the end-side electrodes 6a, 8a of the terminal electrodes 6, 8, and an upper surface coating layer 18 is formed on the upper surface 4c perpendicular to the Z-axis of the element body 4.

Next, the surfaces of the upper electrodes 6b and 8b, the surface of the top coating layer 18, and the ends of the end coating layer 18b in the Z-axis direction are polished to be flush with each other. If a plating film is formed on the surfaces of the upper electrodes 6b and 8b, the plating film and the surface of the top coating layer 18 may be polished to be flush with each other.

In the multilayer ceramic capacitor 2 of this embodiment, a conductive metal film 5 is interposed at the interface between the element body 4 and the terminal electrodes 6, 8. This configuration can increase the adhesion between the terminal electrodes 6, 8 and the surface of the element body 4. As a result, improved adhesion between the terminal electrodes 6, 8 and the element body 4 is achieved, and moisture resistance can be improved.

Twelfth embodiment As shown in Fig . 8A2 , the multilayer ceramic capacitor 2 according to this embodiment is similar to the multilayer ceramic capacitor 2 according to the eleventh embodiment, except as described below. This multilayer ceramic capacitor 2 has a side coating layer 18a provided continuously with the top surface coating layer 18 of the eleventh embodiment on the side surfaces 4e facing each other along the X-axis direction of the element body 4. This configuration further improves the strength of the multilayer ceramic capacitor 2. The side coating layer 18a of this embodiment is similar to the side coating layer 18a of the second embodiment.

7B and 8B , the multilayer ceramic capacitor 2a according to this embodiment is similar to the multilayer ceramic capacitor 2 according to the eleventh embodiment, except as described below. In this multilayer ceramic capacitor 2a, the upper surface 4c of the element body 4 includes an upper surface reinforcement layer 16 made of a material having a higher strength than the inner dielectric layer 10. The upper surface reinforcement layer 16 of this embodiment is similar to the upper surface reinforcement layer 16 of the third embodiment.

14th embodiment As shown in Fig . 8C , the multilayer ceramic capacitor 2b according to this embodiment is similar to the multilayer ceramic capacitor 2a according to the 13th embodiment, except as described below. In this multilayer ceramic capacitor 2b, a side reinforcement layer 16a is provided on the side surface 4e of the element body 4 facing each other along the X-axis direction, and is continuous with the upper surface reinforcement layer 16 according to the 13th embodiment. This configuration further improves the strength of the multilayer ceramic capacitor 2. The side reinforcement layer 16a according to this embodiment is similar to the side reinforcement layer 16a according to the fourth embodiment.

Fifteenth embodiment As shown in Fig . 7C , a multilayer ceramic capacitor 2c according to this embodiment is similar to the multilayer ceramic capacitor 2a according to the embodiment shown in Fig. 7B , except as described below. In this multilayer ceramic capacitor 2c, a reinforcement layer 116 similar to the upper surface reinforcement layer 16 formed on the upper surface 4c of the element body 4 shown in Fig. 7B is formed on the lower surface 4d of the element body 4.

The method of forming the reinforcing layer 116 covering the lower surface 4d is not particularly limited. The reinforcing layer 116 covering the lower surface 4d is formed, for example, by applying a reinforcing layer paste to the lower surface 4d of the element body 4d of the element body 4 and baking it, and then forming the conductive metal film 5 and the terminal electrodes 6, 8. Alternatively, the reinforcing layer paste may be applied to the lower surface 4d of the element body 4 on which the conductive metal film 5 and the terminal electrodes 6, 8 have been formed, and then baked to form the reinforcing layer. After baking, the outer surface of the reinforcing layer 116 covering the lower surface 4d may be polished flat. The other configurations and effects are the same as those of the above-mentioned embodiment.

Twenty-First Embodiment As shown in FIG . 13A , the multilayer ceramic capacitor 2 according to this embodiment is similar to the multilayer ceramic capacitor 2 according to the first embodiment, except for the following points.

13A , the multilayer ceramic capacitor 2 according to this embodiment has a reinforcing layer 116 that covers the element body 4 continuously from the side surfaces 4e, 4e facing each other in the X-axis direction to the upper surface 4c. This can improve the bending strength of the element body 4, and can prevent damage to the multilayer ceramic capacitor 2.

Fig. 14A is a cross-sectional view taken along line IIA-IIA in Fig. 13A . As shown in Fig . 14A , the reinforcing layer 116 covering the side surfaces 4e, 4e of the element body 4 may be in contact with the end of the internal electrode layer 12 in the X-axis direction.

The reinforcing layer 116 covering the top surface 4c and the reinforcing layer 116 covering the side surfaces 4e, 4e are formed on the top surface 4c and the side surfaces 4e, 4e of the element body 4 after the element body 4 is formed and before the terminal electrodes 6, 8 are formed.

The reinforcing layer 116 in this embodiment includes a filler and a substrate.

In this embodiment, the shape of the filler in the reinforcing layer 116 is needle-like, columnar, or plate-like. In this embodiment, it is preferable that the shape of the filler is needle-like. This allows the formation of a stronger reinforcing layer 116.

In this embodiment, the particle size of the filler in the short axis direction is not particularly limited. In this embodiment, the particle size of the filler in the short axis direction is preferably 0.1 μm or more and 3.0 μm or less.

In this embodiment, since the particle size of the filler in the short axis direction is within the above range, the bending strength of the multilayer ceramic capacitor 2 can be increased. In addition, the adhesion between the reinforcing layer 116 covering the upper surface 4c and the upper electrode portions 6b and 8b can be increased, and as a result, the moisture resistance of the multilayer ceramic capacitor 2 can be improved. In this embodiment, the particle size of the filler in the short axis direction is more preferably 0.5 μm or more and 3.0 μm or less.

In this embodiment, the particle size of the filler in the long axis direction is not particularly limited. In this embodiment, the particle size of the filler in the long axis direction is preferably 0.5 μm or more and 15.0 μm or less.

In this embodiment, since the particle size of the filler in the long axis direction is within the above range, the bending strength of the multilayer ceramic capacitor 2 can be increased. In addition, the adhesion between the reinforcing layer 116 covering the upper surface 4c and the upper electrode portions 6b and 8b can be increased, and as a result, the moisture resistance of the multilayer ceramic capacitor 2 can be increased.

In this embodiment, the particle size of the filler in the major axis direction is more preferably 3.0 μm or more and 15.0 μm or less.

In this embodiment, the aspect ratio (%) of the filler, expressed as (particle diameter of minor axis/particle diameter of major axis) x 100, is not particularly limited. In this embodiment, the aspect ratio of the filler is preferably 0.7% or more and 60% or less.

In this embodiment, since the aspect ratio of the filler is within the above range, the bending strength of the multilayer ceramic capacitor 2 can be increased. In addition, the adhesion between the reinforcing layer 116 covering the upper surface 4c and the upper electrode portions 6b and 8b can be increased, and as a result, the moisture resistance of the multilayer ceramic capacitor 2 can be improved. In this embodiment, the aspect ratio of the filler is more preferably 0.7% or more and 30% or less.

In this embodiment, the method for forming the filler with the above-mentioned shape and size is not particularly limited. For example, a mixing type method is used in which filler having the above-mentioned shape and size is added to the reinforcing layer paste for forming the reinforcing layer 116, and when the filler is glass, a precipitation type method is used in which a predetermined glass raw material is added to the reinforcing layer paste for forming the reinforcing layer 116, and the paste is baked at a baking temperature or baking time within a predetermined range.

In this embodiment, it is preferable to use a precipitation method to make the shape and size of the filler as described above. The baking temperature in the precipitation method of this embodiment is preferably 50°C or more higher than the softening point of the "glass contained in the reinforced layer 116" described below. By increasing the baking temperature, the glass tends to be sintered densely. Furthermore, it is more preferable that the baking temperature in the precipitation method of this embodiment is 50°C to 80°C higher than the softening point of the "glass contained in the reinforced layer 116" described below.

The baking time for the precipitation-type method of this embodiment is preferably 0.1 to 2 hours. By extending the baking time, the glass tends to be densely sintered. Also, the baking time for the precipitation-type method of this embodiment is preferably 0.1 to 1 hour.

In this embodiment, the filler content in the reinforcement layer 116 is not particularly limited. In this embodiment, the filler content in the reinforcement layer 116 is preferably 30% by volume or more and 80% by volume or less, and more preferably 45% by volume or more and 80% by volume or less.

In this embodiment, since the filler content in the reinforcement layer 116 is within the above range, the bending strength of the multilayer ceramic capacitor 2 can be increased. In addition, the adhesion between the reinforcement layer 116 covering the upper surface 4c and the upper electrode portions 6b and 8b can be increased, and as a result, the moisture resistance of the multilayer ceramic capacitor 2 can be improved. In this embodiment, the filler content in the reinforcement layer 116 is more preferably 55% by volume or more and 80% by volume or less.

The material of the filler constituting the reinforcing layer 116 of this embodiment is not particularly limited. The material of the filler of this embodiment is preferably glass or alumina. This can increase the bending strength of the multilayer ceramic capacitor 2. In addition, the adhesion between the reinforcing layer 116 covering the upper surface 4c and the upper electrode portions 6b and 8b can be increased, and as a result, the moisture resistance of the multilayer ceramic capacitor 2 can be increased.

The filler material of this embodiment is preferably glass containing at least one of Si and Al as a main component. The main component is a component that is contained in the glass at 30% to 70% by mass. The filler material of this embodiment is more preferably glass containing Si and Al as main components.

In this embodiment, the filler material is preferably glass containing alkali metals, alkaline earth metals, transition metals, and boron as minor components.

The filler material is glass containing one or more sub-components selected from the group consisting of alkali metals, alkaline earth metals, transition metals, and boron, which makes it easier to plate the upper electrode portions 6b and 8b when forming them by plating on a portion of the surface of the reinforced layer 116 that covers the upper surface 4c.

The alkali metal contained as a secondary component in the glass that is the filler material of this embodiment is not particularly limited. Examples of the alkali metal contained as a secondary component in the glass that is the filler material of this embodiment are Li, Na, and K.

Examples of alkaline earth metals contained as secondary components in the glass, which is the filler material of this embodiment, include Ba, Ca, and Sr.

The material of the substrate constituting the reinforcing layer 116 in this embodiment is not particularly limited. The material of the substrate in this embodiment is preferably at least one of glass and resin. It is more preferable that the material of the substrate in this embodiment is glass.

For example, if the substrate contains glass and resin, it is preferable that the reinforcing layer 116 contains 10 to 40 parts by weight of resin per 100 parts by weight of glass.

In this embodiment, it is more preferable that the reinforced layer 116 contains 15 to 30 parts by weight of resin per 100 parts by weight of glass.

In this embodiment, the reinforcing layer 116 is formed from a reinforcing layer paste, which contains a resin mainly composed of ethyl cellulose to give the reinforcing layer paste viscosity. If the substrate contains glass and a binder removal process is performed during manufacturing, the resin mainly composed of ethyl cellulose in the reinforcing layer paste will be burned away and will not be present in the completed product.

The material of the substrate in this embodiment is more preferably glass containing at least one of Si and Al as its main component. Note that a main component is a component that is contained in the glass at 30% to 70% by mass. The material of the substrate in this embodiment is even more preferably glass containing Si and Al as its main components.

In this embodiment, the substrate material is preferably glass containing alkali metals, alkaline earth metals, transition metals, and boron as minor components.

The alkali metals contained as minor components in the glass that is the material of the substrate in this embodiment are not particularly limited. Examples of alkali metals contained as minor components in the glass that is the material of the substrate in this embodiment are Li, Na, and K.

Examples of alkaline earth metals contained as minor components in the glass, which is the material of the substrate in this embodiment, include Ba, Ca, and Sr.

The resin material of the substrate of this embodiment is not particularly limited. The resin material of the substrate of this embodiment is a polyimide resin or an epoxy resin. The resin material of the substrate of this embodiment is preferably a polyimide resin. The resin material of the substrate of this embodiment may be used alone or in combination of two or more types.

In this embodiment, when both the filler and the substrate of the reinforced layer 116 are glass, when only the filler of the reinforced layer 116 is glass, or when only the substrate is glass, the composition of each glass is not limited. In this embodiment, when both the filler and the substrate of the reinforced layer 116 are glass, when only the filler of the reinforced layer 116 is glass, or when only the substrate is glass, the composition of each glass is preferably as follows. Hereinafter, these glasses are collectively referred to as "glass contained in the reinforced layer 116". Note that when both the filler and the substrate of the reinforced layer 116 are glass, the composition is the total composition of the filler and the substrate, which is the sum of the elements contained in the filler and the substrate.

The glass contained in the reinforced layer 116 of this embodiment is the same as the glass component constituting the upper surface reinforced layer 16 of the third embodiment.

In addition, the glass contained in the reinforced layer 116 of this embodiment contains an alkali metal, a transition metal, and boron, which can lower the softening point of the glass and makes it easier to precipitate the filler that constitutes the reinforced layer 116.

In addition, the transition metal used in the reinforcing layer 116 of this embodiment is preferably V or Zn. This makes it easier to form plating as the upper electrode parts 6b and 8b, and also makes it easier to precipitate the filler that constitutes the reinforcing layer 116.

In addition, the composition of the glass contained in the reinforced layer 116 in this embodiment may be the same as or different from the glass constituting the upper surface coating layer 18 or the end side coating layer 18b described below.

By configuring the glass contained in the reinforced layer 116 of this embodiment as described above, a predetermined filler can be precipitated. As a result, the strength of the reinforced layer 116 becomes higher than that of the inner dielectric layer 10. Therefore, the bending strength of the multilayer ceramic capacitor 2 is further improved. In addition, the improved strength makes it easy to increase the longitudinal dimension y0 (see FIG. 13A ) or width dimension x0 (see FIG. 14A ) of the element body 4 even if the element body 4 is thinned, and the opposing area between the internal electrode layers 12 inside the element body 4 becomes wider, thereby further improving the characteristics of the multilayer ceramic capacitor 2, such as the electrostatic capacitance.

From the above viewpoints, the relative thickness of the reinforcing layer 116 calculated from the formula (average thickness of the reinforcing layer 116/average thickness of the upper electrode portions 6b, 8b) x 100 is preferably 20% to 133%, and more preferably 50% to 100%.

Next, we will explain in detail the manufacturing method of the multilayer ceramic capacitor 2 as one embodiment of the present invention.

First, the element body 4 is obtained in the same manner as in the first embodiment. Next, as shown in Fig. 16 , for example, a dummy block 20 is temporarily bonded between the lower surfaces 4d, 4d of the two element bodies 4, 4, and a work 22 is formed by integrating these. At the stage where the work 22 is formed, a reinforcing layer paste is applied from the side surface 4e to the upper surface 4c of the element body 4, and baked to form a reinforcing layer 116.

When the filler is glass and the substrate is glass, the paste for the reinforcing layer is obtained, for example, by kneading in a mixer a glass raw material containing the components constituting the reinforcing layer 116 described above, a resin whose main component is ethyl cellulose, and terpineol and acetone as dispersion media.

When the filler is glass and the substrate is resin, the reinforcing layer paste can be obtained, for example, by kneading glass containing the components that make up the filler, a specified resin, and terpineol and acetone as dispersion media in a mixer.

The method of applying the reinforcing layer paste to the element body 4 is not particularly limited. Examples of methods for applying the reinforcing layer paste to the element body 4 include dipping, printing, coating, vapor deposition, spraying, and the like. In this embodiment, it is preferable to apply the reinforcing layer paste to the element body 4 in multiple layers. Specifically, after applying one layer of the reinforcing layer paste, it is dried, and then another layer of the reinforcing layer paste is applied on top of that and dried. It is preferable to repeat this process and stack 2 to 10 layers of the reinforcing layer paste. This can increase the density of the reinforcing layer 116 and reduce voids in the reinforcing layer 116. As a result, a reinforcing layer 116 with higher strength can be obtained.

Furthermore, the reinforcement layer 116 obtained by the above method has excellent moisture resistance from the upper surface 4c because of the high adhesion between the reinforcement layer 116 covering the upper surface 4c and the upper electrode portions 6b and 8b.

The conditions for baking the element body 4 coated with the reinforcing layer paste of this embodiment are not particularly limited, and the element body 4 may be baked, for example, in an atmosphere of humidified _N2 or dry _N2 .

In this embodiment, when the filler is glass, needle-shaped, columnar, or plate-shaped fillers can be obtained by firing at a temperature 50°C or more higher than the softening point of the glass that constitutes the filler. In this embodiment, it is preferable to fire at a temperature 50°C to 80°C higher than the softening point of the glass that constitutes the filler.

Specifically, the softening point of the glass that constitutes the filler is preferably 600°C to 850°C, and the baking temperature is preferably 650°C to 930°C. In addition, the baking time is preferably 0.1 to 2 hours.

Next, the workpiece 22 is attached to the through hole 32 of the holding plate 30, and the terminal electrodes 6 and 8 are formed.

After the terminal electrodes 6, 8 are formed, the two element bodies 4, 4 are separated by, for example, removing the dummy block 20, thereby obtaining the multilayer ceramic capacitor 2 shown in Fig. 13A . In other words, the multilayer ceramic capacitor 2 in which the terminal electrodes 6, 8 are not substantially formed on the lower surface 4d of the element body 4 is obtained.

13B , the multilayer ceramic capacitor 2a according to this embodiment is similar to the multilayer ceramic capacitor 2 according to the 21st embodiment, except as described below. In this embodiment, an upper surface covering layer 18 covering the upper surface 4c of the element body 4 located between a pair of upper electrode portions 6b, 8b is present in close contact with the surfaces of the upper electrode portions 6b, 8b so as to be substantially flush with them. The upper surface covering layer 18 according to this embodiment is similar to the upper surface covering layer 18 according to the first embodiment.

In this embodiment, the outer surfaces of the end electrode portions 6a and 8a are covered with end coating layers 18b. The end coating layers 18b in this embodiment are similar to the end coating layers 18b in the first embodiment.

13C , the multilayer ceramic capacitor 2b according to this embodiment is similar to the multilayer ceramic capacitor 2a according to the twenty-second embodiment, except for the following: In this embodiment, the entire lower surface 4d of the element body 4 is covered with a reinforcing layer 116.

Here, "the entire surface of the lower surface 4d" means that the entire surface of the lower surface 4d is generally covered, but some parts may be uncovered. For example, the coverage rate of the reinforcing layer 116 calculated from the formula (area of the reinforcing layer 116 covering the lower surface 4d/area of the lower surface 4d) x 100 may be 90% to 100%. This allows the bending strength to be increased even if the multilayer ceramic capacitor 2b is made thinner.

In addition, in this embodiment, the thickness of the reinforcement layer 116 covering the lower surface 4d, the thickness of the reinforcement layer 116 covering the side surface 4e, and the thickness of the reinforcement layer 116 covering the upper surface 4c may be the same as or different from each other.

The thickness of the reinforcing layer 116 covering the lower surface 4d in this embodiment is not particularly limited, but it is preferable that the thickness of the reinforcing layer 116 covering the lower surface 4d is thinner than the thickness of the reinforcing layer 116 covering the upper surface. This prevents the dimension in the Z-axis direction from becoming too large, allowing for problem-free implementation.

In addition, in this embodiment, the surface of the reinforcement layer 116 covering the lower surface 4d is a flat surface. Since the outer surface of the reinforcement layer 116 covering the lower surface 4d is a flat surface, it becomes easier to embed the multilayer ceramic capacitor 2b inside the multilayer substrate 40. Furthermore, when the flat surface of the reinforcement layer 116 covering the lower surface 4d is placed on the mounting surface, the multilayer ceramic capacitor 2c is attached in close contact with the mounting surface, improving the bending strength of the multilayer ceramic capacitor 2b.

The method of forming the reinforcing layer 116 covering the lower surface 4d is not particularly limited. The reinforcing layer 116 covering the lower surface 4d is formed, for example, by applying a reinforcing layer paste to the lower surface 4d of the element body 4d and baking it, and then forming the terminal electrodes 6, 8 and the end side covering layer 18b. Alternatively, the reinforcing layer paste may be applied to the lower surface 4d of the element body 4d on which the terminal electrodes 6, 8 and the end side covering layer 18b have been formed, and then baking it. After baking, the outer surface of the reinforcing layer 116 covering the lower surface 4d may be polished flat.

Other embodiments The present invention is not limited to the above-mentioned embodiments, and may be modified in various ways or may be combined with each other. For example, the upper surface reinforcement layer 16 shown in Figures 1B, 2B, 2C, 7B , 8B , and 8C , the side reinforcement layer 16a shown in Figures 2C and 8C , and/or the reinforcement layer 116 shown in Figure 7C may be the reinforcement layer 116 shown in Figures 13A to 18. Specifically, the upper surface reinforcement layer 16, the side reinforcement layer 16a, and/or the reinforcement layer 116 include a filler and a matrix, the material of the filler is glass or alumina, and the shape of the filler may be needle-like, columnar, or plate-like.

In the first to third and eleventh to thirteenth embodiments, the upper surface 4c of the element body 4 located between the pair of upper electrode portions 6b, 8b is covered with the upper surface coating layer 18, but the upper surface 4c of the element body 4 does not have to be covered with the upper surface coating layer 18.

In the 31st to 33rd embodiments, the reinforcing layer 116 may be formed only on the upper surface 4c of the element body 4, may be formed only on the lower surface 4d, or may be formed only on the side surface 4e. In addition, the reinforcing layer 116 does not have to be formed on both of the pair of side surfaces 4e, 4e, and may be formed only on one of the side surfaces 4e.

The above describes the firing method when the filler is glass and the substrate is glass, but the firing method when the filler is alumina is as follows.

First, if the filler is alumina and the substrate is glass, it is as follows:

Needle-, column- or plate-shaped alumina is mixed in advance with the glass raw material that will become the substrate after firing into the paste for the reinforcing layer. This paste for the reinforcing layer is then applied to the element body 4 in the same manner as above.

The baking conditions for the element body 4 coated with the reinforcing layer paste are, for example, a baking temperature of 650° C. to 930° C. in a humidified N ₂ or dry N ₂ atmosphere, and a baking temperature holding time of 0.1 to 2 hours.

Also, if the filler is alumina and the substrate is resin, it is as follows:

Acicular, columnar or plate-shaped alumina is mixed in advance with the resin that will become the substrate after baking into the reinforcing layer paste. This reinforcing layer paste is then applied to the element body 4 in the same manner as above.

The baking conditions for the element body 4 coated with the reinforcing layer paste are, for example, a baking temperature of 250°C to 450°C in a humidified _N2 or dry _N2 atmosphere, and a baking temperature holding time of 0.1 to 2 hours. The above is an example of the baking method when the filler is alumina.

4, 10 and 16 , when one or more element bodies 4 are arranged and bonded, only the end electrode portions 6a, 8a and the side electrode portions 6c, 8c are formed on those element bodies 4. That is, in that case, a multilayer ceramic capacitor 2 having terminal electrodes on both the lower surface 4d and the upper surface 4c of the element body 4 where the terminal electrodes 6, 8 are not substantially formed is obtained. Since this multilayer ceramic capacitor 2 has terminal electrodes on both the lower surface 4d and the upper surface 4c of the element body 4 where the terminal electrodes 6, 8 are not substantially formed, an even thinner multilayer ceramic capacitor 2 is obtained.

The order in which the coating layers are formed is not limited. For example, the end coating layer 18b may be formed first, and then the top coating layer 18 may be formed. Furthermore, if the materials of the top coating layer 18 and the end coating layer 18b are substantially the same, the top coating layer 18 and the end coating layer 18b may be formed simultaneously.

The multilayer ceramic capacitor 2 of this embodiment may be mounted on a circuit board 40a using solder 50, as shown in Figures 6, 12 , and 18. In that case, the multilayer ceramic capacitor 2 is disposed upside down in the Z-axis direction, and the upper electrode portions 6b, 8b of the terminal electrodes 6 and 8 face downward in the drawings and are connected to the wiring pattern 42a of the circuit board 40a by the solder 50. A solder fillet is formed in the solder 50, and the solder 50 also comes into contact with the end electrode portions 6a, 8a of the terminal electrodes 6, 8.

In each of the above embodiments, the longitudinal direction of the multilayer ceramic capacitor 2 is the Y-axis direction, and the short side direction of the multilayer ceramic capacitor 2 is the X-axis direction, but the longitudinal direction of the multilayer ceramic capacitor can also be designed to be the X-axis direction and the short side direction of the multilayer ceramic capacitor to be the Y-axis direction. That is, the distance between the two opposing external electrodes 6, 8 can be shorter than the distance between the two opposing side surfaces 4e, 4e. In this case, the length x0 in the X-axis direction can be three times or more the thickness z0, preferably 300 μm or more, and preferably 400 μm to 1200 μm. In addition, the width y0 of the multilayer ceramic capacitor in the y-axis direction can be two times or more the thickness z0, preferably 200 μm or more, and preferably 200 μm to 600 μm.

The multilayer ceramic electronic component of the present invention is not limited to multilayer ceramic capacitors, and can be applied to other multilayer electronic components. Other multilayer electronic components include all electronic components in which dielectric layers (insulating layers) are laminated via internal electrodes, such as bandpass filters, inductors, multilayer three-terminal filters, piezoelectric elements, PTC thermistors, NTC thermistors, and varistors.

The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[Experiment 1]
Sample No. 1
A multilayer ceramic capacitor 2 of sample number 1 was fabricated as follows.

First, 100 parts by mass of _BaTiO3 -based ceramic powder, 10 parts by mass of polyvinyl butyral resin, 5 parts by mass of dioctyl phthalate (DOP) as a plasticizer, and 100 parts by mass of alcohol as a solvent were mixed in a ball mill to form a paste, thereby obtaining a paste for the inner green sheet.

Separately from the above, 44.6 parts by weight of Ni particles, 52 parts by weight of terpineol, 3 parts by weight of ethyl cellulose, and 0.4 parts by weight of benzotriazole were mixed using a triple roll mill to form a slurry, to prepare a paste for the internal electrode layers.

An inner green sheet was formed on a PET film using the inner green sheet paste prepared above. Next, an inner electrode pattern layer was formed in a predetermined pattern using the inner electrode layer paste, and the sheet was then peeled off from the PET film to obtain an inner green sheet with an inner electrode pattern layer.

The inner green sheets having the internal electrode pattern layers thus obtained were alternately stacked to produce an inner laminate.

Next, an appropriate number of outer green sheets were formed above and below the internal laminate using the paste for the outer green sheets, and the sheets were pressed and bonded in the lamination direction to obtain a green laminate. The paste for the outer green sheets was obtained in the same manner as the paste for the inner green sheets.

Next, the green laminate was cut to obtain green chips.

Next, the obtained green chip was subjected to binder removal, firing, and annealing under the following conditions to obtain the element body 4.

The conditions for the binder removal process were: heating rate 60°C/hour, holding temperature: 260°C, holding time: 8 hours, atmosphere: air.

The firing conditions were a temperature rise rate of 200° C./hour, a holding temperature of 1000° C. to 1200° C., and a temperature holding time of 2 hours. The cooling rate was 200° C./hour. The atmospheric gas was a humidified N ₂ +H ₂ mixed gas.

The annealing conditions were as follows: heating rate: 200°C/hour, holding temperature: 500°C to 1000°C, temperature holding time: 2 hours, cooling rate: 200°C/hour, atmospheric gas: humidified _N2 gas.

A wetter was used to humidify the atmospheric gas during firing and annealing.

Next, as shown in FIG. 4, a dummy block 20 was temporarily bonded between the lower surfaces 4d, 4d of the two element bodies 4, 4 to form a workpiece 22 by integrating these together, and the workpiece 22 was then attached to the through hole 32 of the holding plate 30.

Next, 100 parts by weight of a mixture of spherical Cu particles with an average particle size of 0.4 μm and flake-shaped Cu powder, 30 parts by weight of an organic vehicle (5 parts by weight of ethyl cellulose resin dissolved in 95 parts by weight of butyl carbitol), and 6 parts by weight of butyl carbitol were kneaded to obtain a paste for terminal electrodes.

The obtained terminal electrode paste was applied by dipping onto the end faces in the Y-axis direction of the ceramic sintered body, and fired at 850° C. for 10 minutes in a N ₂ atmosphere to form terminal electrodes 6 and 8.

Next, the dummy block 20 was removed to separate the two element bodies 4, 4.

Next, Si-B-Zn-O glass powder with a softening point of 600°C, a binder mainly composed of ethyl cellulose, and terpineol and acetone as dispersion media were mixed in a mixer to prepare a paste for the coating layer.

A pre-baked end-side coating layer was printed on the outer surfaces of the end-side electrode portions 6a, 8a of the terminal electrodes 6, 8 using a coating layer paste.

After printing, the dried chip was held in an N ₂ atmosphere at 700° C. for 0.1 hour to bake the end side covering layer 18b.

The thickness of the multilayer ceramic capacitor 2 was 60 μm. The thickness of the upper electrode portions 6b, 8b was 15 μm, the thickness of the end electrode portions 6a, 8a was 10 μm, and the relative thickness of the end coating layer 18b was 100%. Furthermore, the coverage rate of the end coating layer 18b was 99%. The coverage rate of the end coating layer 18b was measured by observing the end surface with a SEM.

Sample No. 2
For sample number 2, a multilayer ceramic capacitor 2 was produced in the same manner as sample number 1, except that end side covering layers 18b were not formed. The specifications of sample number 2 are shown in Table 1.

Sample No. 3
In sample number 3, a multilayer ceramic capacitor 2 was fabricated in the same manner as sample number 1, except that the material of end covering layer 18b was changed to Si-Al-MO based glass. The specifications of sample number 3 are shown in Table 1.

Sample No. 4
In sample number 4, the material of end side covering layer 18b was changed to polyimide resin, and the coverage rate of end side covering layer 18b was changed to 96%, but other than that, multilayer ceramic capacitor 2 was fabricated in the same manner as sample number 1. The specifications of sample number 4 are shown in Table 1.

Sample No. 5
For sample number 5, a multilayer ceramic capacitor 2 was produced in the same manner as sample number 1, except that the coverage of end side covering layer 18b was changed to 90%. The specifications of sample number 5 are shown in Table 1.

Samples No. 6 and 7
For sample numbers 6 and 7, multilayer ceramic capacitors 2 were fabricated in the same manner as sample number 1, except that the relative thickness of end covering layer 18b was changed as shown in Table 1. The specifications of sample numbers 6 and 7 are shown in Table 1.

Sample No. 8
For sample number 8, the multilayer ceramic capacitor 2 was produced in the same manner as for sample number 1, except for the inclusion of a step of forming the top surface coating layer 18. For sample number 8, after the end side coating layer 18b was formed, the top surface coating layer 18 was formed in the same manner as the end side coating layer 18b, and the surfaces of the upper electrode portions 6b, 8b, the surface of the top surface coating layer 18, and the ends in the Z-axis direction of the end side coating layer 18b were polished so as to be substantially flush with each other, thereby obtaining the multilayer ceramic capacitor 2. The relative thickness of the top surface coating layer 18 was 90 to 110%. The specifications of sample number 8 are shown in Table 1.

<Insulation IR after humidity load test>
The obtained multilayer ceramic capacitor 2 was immersed in an acidic solution, and then the insulation resistance was measured at 121° C., 95% RH, 20 hrs, and 6.3 V was applied. The relative values of each sample, with the insulation resistance value of sample number 2 set as 100%, are shown in Table 1. The insulation resistance value of sample number 2 was 1× ¹⁰ Ω.

<Three-point bending strength>
The three-point bending strength of the obtained multilayer ceramic capacitor 2 was measured using a measuring device (product name: 5543, manufactured by Instron). The jig distance between two points supporting the test piece during the measurement was 400 μm, the measurement speed was 0.5 mm/min, and the average value (unit: MPa) of the values obtained by measuring 10 test pieces was measured. The relative values of each sample when the three-point bending strength of sample number 2 was set to 100% are shown in Table 1. The three-point bending strength of sample number 2 was 200 MPa.

From Table 1, it was confirmed that when the outer surface of the end electrode portion is covered with an end coating layer (sample number 1), the insulation IR after the moisture resistance load test is better and the three-point bending strength is better than when the outer surface of the end electrode portion is not covered with an end coating layer (sample number 2).

From Table 1, it was confirmed that the insulating IR and three-point bending strength after the moisture load test were good even when the material of the end coating layer was Si-Al-M-O glass (sample number 3) and when the material of the end coating layer was polyimide resin (sample number 4).

From Table 1, it was confirmed that when the coverage rate of the end side coating layer was over 90% (sample numbers 1, 3, and 4), the insulating IR after the moisture resistance load test was better than when the coverage rate of the end side coating layer was 90% (sample number 5).

From Table 1, it was confirmed that when the relative thickness of the end coating layer was 20 to 500% (sample numbers 1, 6, and 7), the insulating IR and three-point bending strength after the moisture resistance load test were better than when the outer surface of the end electrode part was not covered with the end coating layer (sample number 2).

From Table 1, it can be seen that when there is a top surface coating layer in addition to the end side coating layer (sample number 8), the three-point bending strength is better.

[Experiment 2]
Sample No. 101
A multilayer ceramic capacitor 2 of sample number 101 was fabricated as follows.

First, an element body 4 was obtained in the same manner as in Experiment 1. Next, as shown in Fig. 10A , a conductive metal film 5 was formed by a sputtering device on the surface of the element body 4 on which a resist film 60 was formed in a predetermined pattern. The types of conductive metal films 5 are shown in Table 11. As shown in Fig. 8A3 , the coverage area ratio of the metal film 5 filling the concave portions of the uneven surface of the element body 4 was 20% as shown in Table 11.

Thereafter, the resist film 60 is removed, and as shown in FIG. 10B , a dummy block 20 is temporarily adhered between the lower surfaces 4d, 4d of the two element bodies 4, 4 to form a workpiece 22 by integrating these together, and the workpiece 22 is then attached to the through hole 32 of the holding plate 30.

Next, 100 parts by weight of a mixture of spherical Cu particles with an average particle size of 0.4 μm and flake-shaped Cu powder, 30 parts by weight of an organic vehicle (5 parts by weight of ethyl cellulose resin dissolved in 95 parts by weight of butyl carbitol), and 6 parts by weight of butyl carbitol were kneaded to obtain a paste for terminal electrodes.

The obtained terminal electrode paste was applied by dipping to the end faces of the ceramic sintered body in the Y-axis direction, and fired in a _N2 atmosphere at 850°C for 10 minutes to form terminal electrodes 6, 8 on the surface of the conductive metal film 5 of the element body 4.

Next, the dummy block 20 was removed to separate the two element bodies 4, 4.

Next, Si-B-Zn-O glass powder with a softening point of 600°C, a binder mainly composed of ethyl cellulose, and terpineol and acetone as dispersion media were mixed in a mixer to prepare a paste for the coating layer.

A pre-baked end-side coating layer was printed on the outer surfaces of the end-side electrode portions 6a, 8a of the terminal electrodes 6, 8 using a coating layer paste.

After printing, the chip was dried and held in an _N2 atmosphere at 700° C. for 0.1 hour to bake the end side covering layer 18b. The material of the end side covering layer is shown in Table 11.

The thickness of the multilayer ceramic capacitor 2 was 60 μm. The thickness of the upper electrode portions 6b, 8b was 15 μm, the thickness of the end electrode portions 6a, 8a was 10 μm, and the relative thickness of the end coating layer 18b was 100%. Furthermore, the coverage rate of the end coating layer 18b was 99%. The coverage rate of the end coating layer 18b was measured by observing the end surface with a SEM.

Sample No. 102
For sample number 102, the sputtering time was set long, the coverage of the metal film 5 was set to 70%, and the end side covering layer 18b was not formed, except that a multilayer ceramic capacitor 2 was produced in the same manner as for sample number 101. The specifications of sample number 102 are shown in Table 11.

Sample No. 103
For sample number 103, the sputtering time was set long, the coverage of the metal film 5 was set to 50%, and the material of the end-side covering layer 18b was changed to Si-Al-Ca-O based glass, but other than that, a multilayer ceramic capacitor 2 was fabricated in the same manner as sample number 101. The specifications of sample number 103 are shown in Table 11.

Sample No. 104
For sample number 104, the sputtering time was set long, the coverage of the metal film 5 was set to 50%, and the material of the end side covering layer 18b was changed to polyimide resin, so that the coverage of the end side covering layer 18b was changed to 96%, but other than that, a multilayer ceramic capacitor 2 was fabricated in the same manner as sample number 101. The specifications of sample number 104 are shown in Table 11.

Sample No. 105
For sample number 105, the sputtering time was set long, the coverage of the metal film 5 was set to 70%, and the coverage of the end side covering layer 18b was changed to 90%, but other than that, a multilayer ceramic capacitor 2 was fabricated in the same manner as sample number 101. The specifications of sample number 105 are shown in Table 11.

Sample Nos. 106 and 107
For sample numbers 106 and 107, multilayer ceramic capacitors 2 were fabricated in the same manner as sample number 101, except that the sputtering time was set long, the coverage of metal film 5 was set to 70%, and the relative thickness of end covering layer 18b was changed as shown in Table 11. The specifications of sample numbers 106 and 107 are shown in Table 11.

Sample No. 108
In sample number 108, the multilayer ceramic capacitor 2 was produced in the same manner as sample number 101, except that the sputtering time was set long, the coverage rate of the metal film 5 was set to 50%, and a process of forming the upper surface coating layer 18 was added. In sample number 108, the end side coating layer 18b was formed, and then the upper surface coating layer 18 was formed in the same manner as the end side coating layer 18b. The surfaces of the upper electrode portions 6b and 8b, the surface of the upper surface coating layer 18, and the end portions of the end side coating layer 18b in the Z-axis direction were polished to be substantially flush with each other, thereby obtaining the multilayer ceramic capacitor 2. The relative thickness of the upper surface coating layer 18 was 90 to 110%. The specifications of sample number 108 are shown in Table 11.

Sample Nos. 109 to 114
For sample numbers 109 to 114, multilayer ceramic capacitors 2 were fabricated in the same manner as for sample number 103, except that the type of metal film 5 was changed from Pt to a metal shown in Table 11. The specifications of sample numbers 109 to 114 are shown in Table 11. Note that for sample number 111, the material of the end side covering layer was also changed.

Sample No. 115
For sample number 115, the sputtering time was set to be short, the coverage of the metal film 5 was set to 10%, and the coverage of the end side covering layer 18b was changed to 90%, but other than that, a multilayer ceramic capacitor 2 was fabricated in the same manner as sample number 101. The specifications of sample number 115 are shown in Table 11.

Sample No. 116
For sample number 116, the sputtering time was set long, the coverage of the metal film 5 was set to 90%, and the coverage of the end side covering layer 18b was changed to 90%, but other than that, a multilayer ceramic capacitor 2 was fabricated in the same manner as sample number 101. The specifications of sample number 116 are shown in Table 11.

Sample No. 117
For sample number 117, the multilayer ceramic capacitor 2 was fabricated in the same manner as sample number 101, except that the metal film 5 was not formed and the coverage rate of the end side covering layer 18b was changed to 90%. The specifications of sample number 117 are shown in Table 11.

Sample No. 118
For sample number 118, the multilayer ceramic capacitor 2 was fabricated in the same manner as for sample number 101, except that the metal film 5 was not formed and the end covering layer 18b was not formed. The specifications of sample number 118 are shown in Table 11.

<Insulation IR after humidity load test>
The obtained multilayer ceramic capacitor 2 was immersed in an acidic solution, and then the insulation resistance was measured at 121° C., 95% RH, 20 hrs, and 6.3 V. The relative values of each sample, with the insulation resistance value of sample number 101 taken as 100%, are shown in Table 11. The insulation resistance value of sample number 101 was 1× ¹⁰ Ω.

<Insulating IR after cycle test (IR after thermal shock)>
The obtained multilayer ceramic capacitor 2 was subjected to a series of repeated tests of 2000 cycles, in which the capacitor was held at -55°C for 10 minutes, heated to 125°C for 5 minutes, then held at 125°C for 10 minutes, and cooled to -55°C for 5 minutes. 20 capacitor samples were prepared after this treatment. A direct current voltage of 6.3V was applied to these capacitors for 10 seconds at 20°C using an insulation resistance meter (Advantest R8340A), and the capacitors were left for 20 seconds after application, and the insulation resistance IR (insulation resistance value) was measured. The relative values of each sample when the insulation resistance IR of sample number 101 was taken as 100% are shown in Table 11. The insulation resistance IR of sample number 101 was 1.0 x 10^10Ω.

<Three-point bending strength>
The three-point bending strength was measured in the same manner as in Experiment 1. The relative values of each sample when the three-point bending strength of sample number 102 was taken as 100% are shown in Table 11. The three-point bending strength of sample number 102 was 200 MPa.

From Table 11, it was confirmed that when a conductive metal film is formed and the outer surface of the end electrode portion is covered with an end coating layer (sample number 101), the insulating IR after both the moisture resistance load test and the cycle test are both good, and the three-point bending strength is good, compared to when a conductive metal film is not formed and the outer surface of the end electrode portion is not covered with an end coating layer (sample number 118).

In addition, from Table 11, it was confirmed that when a conductive metal film was formed (sample number 102), the insulating IR after both the moisture resistance load test and the cycle test were better than when a conductive metal film was not formed (sample number 118).

From Table 11, it was confirmed that even when the material of the end side coating layer was Si-Al-Ca-O type glass (sample number 103) and when the material of the end side coating layer was polyimide resin (sample number 104), the insulating IR after the moisture resistance load test, the insulating IR after the cycle test, and the three-point bending strength were better than those of sample number 118.

From Table 11, it was confirmed that when the coverage rate of the end coating layer was over 90% (sample numbers 101, 103, and 104), the insulating IR after both the moisture resistance load test and the cycle test were better than when the coverage rate of the end coating layer was 90% (sample number 105).

From Table 11, it was confirmed that when the relative thickness of the end coating layer was 20 to 500% (sample numbers 101, 106 and 107), the insulating IR after the moisture resistance load test, the insulating IR after the cycle test and the three-point bending strength were better than when the outer surface of the end electrode part was not covered with the end coating layer (sample number 118).

From Table 11, it was confirmed that the three-point bending strength was better when there was a top surface coating layer in addition to the end side coating layer (sample number 108).

From Table 11, it was confirmed that similar results were obtained even if the type of conductive metal film was changed from Pt (sample number 103) to Ru, Rh, Re, Ir, or Pd (sample numbers 109 to 114). It was also confirmed that similar results were obtained even if the type of glass in the end coating layer was changed (sample numbers 109 and 111).

From Table 11, it was confirmed that when the coverage area ratio of the conductive metal film is within the range of 10 and 90% (sample numbers 115 and 116), the insulating IR after both the moisture resistance load test and the cycle test is improved compared to the case where the conductive metal film is not formed (sample number 117).

[Experiment 3]
<Production Example 1>
Sample No. 201
A multilayer ceramic capacitor 2, sample number 201, was fabricated as follows.

As in Experiment 1, as shown in FIG. 16 , a dummy block 20 was temporarily adhered between the lower surfaces 4d, 4d of the two element bodies 4, 4, and a workpiece 22 was formed by integrating these together.

Next, a reinforcing layer 116 was formed to cover the upper surface 4c using the following method.

100 parts by weight of Si-Al-Ca-Zn-O glass, 10 parts by weight of a resin whose main component is ethyl cellulose, 35 parts by weight of terpineol as a dispersion medium, and 20 parts by weight of acetone were kneaded in a mixer to prepare a paste for the reinforcing layer.

The reinforcing layer paste was applied by dipping onto the entire upper surface 4c of the element body 4 of the work 22 perpendicular to the Z axis, and then dried to obtain a chip. Next, the chip was held at 850°C for 0.1 hours in a humidified _N2 atmosphere to bake the reinforcing layer 116 onto the upper surface 4c.

Next, 100 parts by weight of a mixture of spherical Cu particles with an average particle size of 0.4 μm and flake-shaped Cu powder, 30 parts by weight of an organic vehicle (5 parts by weight of ethyl cellulose resin dissolved in 95 parts by weight of butyl carbitol), and 6 parts by weight of butyl carbitol were kneaded to obtain a paste for terminal electrodes.

The obtained terminal electrode paste was applied by dipping onto the end faces in the Y-axis direction of the ceramic sintered body, and fired at 850° C. for 10 minutes in a N ₂ atmosphere to form terminal electrodes 6 and 8.

Next, the dummy block 20 was removed to separate the two element bodies 4, 4.

The specifications of the multilayer ceramic capacitor 2 are shown in Table 1. The thickness of the multilayer ceramic capacitor 2 was 80 μm. In addition, the thickness of the upper electrode portions 6b and 8b was 15 μm, the thickness of the end electrode portions 6a and 8a was 10 μm, and the relative thickness of the reinforcing layer 116 covering the upper surface 4c was 20%.

Sample numbers 202 to 209, 215 to 220
A multilayer ceramic capacitor was obtained in the same manner as sample number 201, except that the filler material, substrate material, filler content, filler shape and size of the reinforcing layer 116 covering the upper surface 4c, and the baking temperature and baking time of the reinforcing layer paste were changed as shown in Table 21 or Table 22. The specifications are shown in Table 21 or Table 22.

Sample No. 210
When forming the reinforcing layer 116 covering the upper surface 4c, alumina in the form of a plate, Si-Al-Zn-O glass, a resin mainly composed of ethyl cellulose, and terpineol and acetone as dispersion media were mixed in a mixer to prepare a paste for the reinforcing layer, and a multilayer ceramic capacitor was obtained in the same manner as sample number 201, except that the baking temperature and baking time of the paste for the reinforcing layer were as shown in Table 21. The specifications are shown in Table 21.

Sample No. 211
A multilayer ceramic capacitor was obtained in the same manner as sample number 210, except that when forming reinforcing layer 116 covering upper surface 4c, columnar alumina was added to the reinforcing layer paste instead of plate-shaped alumina. The specifications are shown in Table 22.

Sample No. 212
When forming the reinforcing layer 116 covering the upper surface 4c, Si-Al-Ca-Zn-Li-B-O glass, polyimide resin, and terpineol and acetone as dispersion media were mixed in a mixer to prepare a reinforcing layer paste, and a multilayer ceramic capacitor was obtained in the same manner as sample number 201, except that the baking temperature and baking time of the reinforcing layer paste were as shown in Table 22. The specifications are shown in Table 22.

Sample No. 213
A multilayer ceramic capacitor was obtained in the same manner as sample number 212, except that when forming the reinforcing layer 116 covering the upper surface 4c, the Si-Al-Ca-Zn-Li-B-O based glass was replaced with plate-like alumina in the reinforcing layer paste, and the baking temperature and baking time of the reinforcing layer paste were set as shown in Table 22. The specifications are shown in Table 22.

Sample No. 214
A multilayer ceramic capacitor was obtained in the same manner as sample number 213, except that when forming the reinforcing layer covering the upper surface 4c, columnar alumina was added to the reinforcing layer paste instead of plate-shaped alumina. The specifications are shown in Table 22.

Sample No. 221
A multilayer ceramic capacitor was obtained in the same manner as sample number 201, except that the reinforcing layer 116 covering the upper surface 4c was not formed. The specifications are shown in Table 22.

<Production Example 2>
Sample Nos. 231-239, 245-250
A multilayer ceramic capacitor was obtained in the same manner as sample number 201, except that the top surface coating layer 18 and the end side coating layers were provided by the following method, and the filler material, substrate material, filler content, filler shape and size of the reinforcing layer 116, as well as the baking temperature and baking time of the reinforcing layer paste were changed as shown in Table 23 or Table 24. The specifications are shown in Table 23 or Table 24.

The method for forming the upper surface covering layer and the end side covering layer was as follows.
First, the dummy block was removed by the method of Manufacturing Example 1 to separate the two element bodies 4, 4, and an element body on which the terminal electrodes 6, 8 were formed was prepared.

Next, Si-B-Zn-O glass powder with a softening point of 600°C, a binder mainly composed of ethyl cellulose, and the dispersion medium terpineol and acetone were mixed in a mixer to prepare a paste for the coating layer.

A pre-baked end-side coating layer was printed on the outer surfaces of the end-side electrode portions 6a, 8a of the terminal electrodes 6, 8 using a coating layer paste.

Next, the above-mentioned coating layer paste was used to print the front-end coating layer between the upper electrode parts 6b and 8b.

After printing, the dried chip was held in an N ₂ atmosphere at 650° C. for 0.1 hour to bake the end side covering layer 18 b and the top surface covering layer 18 .

The surfaces of the upper electrode portions 6b and 8b, the surface of the upper coating layer 18, and the ends of the end coating layer 18b in the Z-axis direction were polished to be flush, obtaining a multilayer ceramic capacitor.

The relative thickness of the end-side coating layer 18b was 100%, the coverage of the end-side coating layer was 99%, and the relative thickness of the upper surface coating layer was 90% to 110%. The coverage of the end-side coating layer was measured by observing the end-side surface with a SEM.

Sample No. 240
A multilayer ceramic capacitor was obtained in the same manner as for sample number 210, except that the upper surface covering layer 18 and the end side covering layer 18b were formed in the same manner as for sample number 231. The specifications are shown in Table 23.

Sample No. 241
A multilayer ceramic capacitor was obtained in the same manner as for sample number 211, except that the upper surface covering layer 18 and the end side covering layer 18b were formed in the same manner as for sample number 231. The specifications are shown in Table 24.

Sample No. 242
A multilayer ceramic capacitor was obtained in the same manner as for sample number 212, except that the upper surface covering layer 18 and the end side covering layer 18b were formed in the same manner as for sample number 231. The specifications are shown in Table 24.

Sample No. 243
A multilayer ceramic capacitor was obtained in the same manner as in sample number 213, except that the upper surface covering layer 18 and the end side covering layer 18b were formed in the same manner as in sample number 231. The specifications are shown in Table 24.

Sample No. 244
A multilayer ceramic capacitor was obtained in the same manner as sample number 214, except that the upper surface covering layer 18 and the end side covering layer 18b were formed in the same manner as sample number 231. The specifications are shown in Table 24.

<Production Example 3>
Sample No. 251 to 270
A multilayer ceramic capacitor was obtained in the same manner as sample number 231, except that a reinforcing layer 116 was not formed on the upper surface 4c, a reinforcing layer 116 was provided to cover the lower surface 4d, and the filler material, substrate material, filler content, filler shape and size of the reinforcing layer 116 covering the lower surface 4d, as well as the baking temperature and time of the reinforcing layer paste were changed as shown in Table 25 or Table 26. The specifications are shown in Table 25.

The method for forming the reinforcing layer 116 covering the lower surface 4d was as follows. First, the entire surface of the lower surface 4d perpendicular to the Z axis of the element body 4 was coated with a reinforcing layer paste by dipping, and then dried to obtain a chip. Next, the reinforcing layer 116 covering the lower surface 4d was baked onto the chip at the baking temperature and for the baking time shown in Table 25 or Table 26. The terminal electrodes 6, 8, end side coating layer 18b, and upper surface coating layer 18 were formed on the element body 4 with the reinforcing layer 116 covering the lower surface 4d baked thereon by the method of Manufacturing Example 2.

The Z-axis end portions of the terminal electrodes 6 and 8 on the lower surface 4d side, the Z-axis end portions of the end-side covering layer 18b on the lower surface 4d side, and the outer surface of the reinforcing layer 116 covering the lower surface 4d were polished to be flat, to obtain a multilayer ceramic capacitor.

Sample No. 260
A multilayer ceramic capacitor was obtained in the same manner as sample number 240, except that the reinforcing layer 116 was not formed on the upper surface 4c, but was formed on the lower surface 4d in the same manner as sample number 251. The specifications are shown in Table 25.

Sample No. 261
A multilayer ceramic capacitor was obtained in the same manner as for sample number 241, except that the reinforcing layer 116 was not formed on the upper surface 4c, but was formed on the lower surface 4d in the same manner as for sample number 251. The specifications are shown in Table 26.

Sample No. 262
A multilayer ceramic capacitor was obtained in the same manner as for sample number 242, except that the reinforcing layer 116 was not formed on the upper surface 4c, but was formed on the lower surface 4d in the same manner as for sample number 251. The specifications are shown in Table 26.

Sample No. 263
A multilayer ceramic capacitor was obtained in the same manner as sample number 243, except that the reinforcing layer 116 was not formed on the upper surface 4c, but was formed on the lower surface 4d in the same manner as sample number 251. The specifications are shown in Table 26.

Sample No. 264
A multilayer ceramic capacitor was obtained in the same manner as sample number 244, except that the reinforcing layer 116 was not formed on the upper surface 4c, but was formed on the lower surface 4d in the same manner as sample number 251. The specifications are shown in Table 26.

<Three-point bending strength>
The three-point bending strength was measured in the same manner as in Experiment 1. The relative values of each sample when the three-point bending strength of sample number 221 was taken as 100% are shown in Tables 21 to 26. The three-point bending strength of sample number 221 was 200 MPa.

<Insulating IR after cycle test (IR after thermal shock)>
The insulation resistance IR (insulation resistance value) was measured in the same manner as in Experiment 2. The relative values of each sample when the insulation resistance IR of sample number 221 was taken as 100% are shown in Tables 21 to 26. The insulation resistance IR of sample number 221 was 7.7×10^9 Ω.

From Tables 21 and 22, it was confirmed that the three-point bending strength was higher when there was a reinforced layer covering the upper surface (sample numbers 201 to 220) than when there was no reinforced layer covering the upper surface (sample number 221).

From Tables 21 and 22, it was confirmed that when there was a reinforced layer covering the top surface (sample numbers 201 to 220), the IR after thermal shock was better than when there was no reinforced layer covering the top surface (sample number 221). This confirmed that when there was a reinforced layer covering the top surface (sample numbers 201 to 220), there was higher adhesion between the top electrode part and the reinforced layer covering the top surface than when there was no reinforced layer covering the top surface.

From Tables 21 to 24, it was confirmed that the three-point bending strength was higher when the upper surface coating layer and the end side coating layer were present (sample numbers 231 to 250) than when the upper surface coating layer and the end side coating layer were not present (sample numbers 201 to 220).

From Tables 25 and 26, it was confirmed that the three-point bending strength was higher when there was a reinforcing layer covering the underside (sample numbers 231 to 250) than when there was no reinforcing layer covering the underside (sample number 221).

DESCRIPTION OF THE REFERENCE NUMERALS 2, 2a, 2b, 2c... Multilayer ceramic capacitor 4... Element body 4a, 4b... Lead-out end 4c... Upper surface 4d... Lower surface 4e... Side surface 5... Conductive metal film 5a... Inner end 6... First terminal electrode 6a... End electrode portion 6b... Upper electrode portion 6c... Side electrode portion 8... Second terminal electrode 8a... End electrode portion 8b... Upper electrode portion 8c... Side electrode portion 10... Inner dielectric layer 11... Exterior region 12... Internal electrode layer 12a, 12b... Lead-out portion 13... Interior region 14... Side gap region 116... Reinforcement layer 16... Upper reinforcement layer 16a... Side reinforcement layer 18... Upper coating layer 18a... Side coating layer 18b... End coating layer 18c... Lower coating layer 20... Dummy block 22... Work 30... Holding plate 32... Through hole 40... Multilayer board 40a... Circuit boards 42, 42a... Wiring pattern 50... Solder 60... Resist film 62... Installation stand

Claims (21)

an element body in which internal electrode layers and insulating layers, which are substantially parallel to a plane including the first axis and the second axis, are alternately laminated along a third axis;
a terminal electrode formed in close contact with an outer surface of the element body and electrically connected to the internal electrode layer,
the terminal electrode has a pair of end-side electrode portions covering an end portion of the element body in the second axial direction from which the internal electrode layer is drawn out and facing each other in the direction of the second axis, and a pair of upper electrode portions each continuously covering a portion of an upper surface of the element body substantially perpendicular to the third axis, the pair of upper electrode portions being continuous with the end-side electrode portions,
The outer surface of the end electrode portion is covered with an end covering layer,
the end-side covering layer is made of glass containing Si as a main component,
a bottom surface of the element body that is located on the opposite side of the top surface of the element body along the third axis, and the terminal electrode is substantially not present on the bottom surface of the element body. an element body in which internal electrode layers and insulating layers, which are substantially parallel to a plane including the first axis and the second axis, are alternately laminated along a third axis;
a terminal electrode formed in close contact with an outer surface of the element body and electrically connected to the internal electrode layer,
the terminal electrode has a pair of end-side electrode portions covering the end portions of the element body in the second axis direction from which the internal electrode layers are drawn out and facing each other in the second axis direction, and a pair of upper electrode portions each continuously covering a portion of an upper surface of the element body substantially perpendicular to the third axis, the pair of upper electrode portions being continuous with the end-side electrode portions,
The outer surface of the end electrode portion is covered with an end covering layer,
the end-side covering layer is made of glass containing Si as a main component,
a lower surface of the element body, the lower surface being located on the opposite side of the upper surface of the element body along the third axis, and the entire lower surface of the element body being exposed to the outside. an element body in which internal electrode layers and insulating layers, which are substantially parallel to a plane including the first axis and the second axis, are alternately laminated along a third axis;
a terminal electrode formed in close contact with an outer surface of the element body and electrically connected to the internal electrode layer,
the terminal electrode has a pair of end-side electrode portions covering the end portions of the element body in the second axis direction from which the internal electrode layers are drawn out and facing each other in the second axis direction, and a pair of upper electrode portions each continuously covering a portion of an upper surface of the element body substantially perpendicular to the third axis, the pair of upper electrode portions being continuous with the end-side electrode portions,
The unevenness formed on the surface of the element body has a surface roughness in the range of 2 to 4 μm as defined in JIS B 0601;
a conductive metal film is interposed between the element body and the terminal electrode;
the coverage area ratio of the uneven surface formed on the surface of the element body covered by the conductive metal film is within a range of 20 to 70%;
The conductive metal film has a thickness of 100 to 500 nm;
a bottom surface of the element body that is located on the opposite side of the top surface of the element body along the third axis, and the terminal electrode is substantially not present on the bottom surface of the element body. an element body in which internal electrode layers and insulating layers, which are substantially parallel to a plane including the first axis and the second axis, are alternately laminated along a third axis;
a terminal electrode formed in close contact with an outer surface of the element body and electrically connected to the internal electrode layer,
the terminal electrode has a pair of end-side electrode portions covering the end portions of the element body in the second axis direction from which the internal electrode layers are drawn out and facing each other in the second axis direction, and a pair of upper electrode portions each continuously covering a portion of an upper surface of the element body substantially perpendicular to the third axis, the pair of upper electrode portions being continuous with the end-side electrode portions,
The unevenness formed on the surface of the element body has a surface roughness in the range of 2 to 4 μm as defined in JIS B 0601;
a conductive metal film is interposed between the element body and the terminal electrode;
the coverage area ratio of the conductive metal film to the uneven surface formed on the surface of the element body is within a range of 20 to 70%;
The conductive metal film has a thickness of 100 to 500 nm;
a lower surface of the element body, the lower surface being located on the opposite side of the upper surface of the element body along the third axis, and the entire lower surface of the element body being exposed to the outside. The multilayer ceramic electronic component according to claim 3 or 4, wherein the conductive metal film contains at least one of the metals Pt, Rh, Ru, Re, Ir, and Pd. an element body in which internal electrode layers and insulating layers, which are substantially parallel to a plane including the first axis and the second axis, are alternately laminated along a third axis;
a terminal electrode formed in close contact with an outer surface of the element body and electrically connected to the internal electrode layer,
the terminal electrode has a pair of end-side electrode portions covering the end portions of the element body in the second axis direction from which the internal electrode layers are drawn out and facing each other in the second axis direction, and a pair of upper electrode portions each continuously covering a portion of an upper surface of the element body substantially perpendicular to the third axis, the pair of upper electrode portions being continuous with the end-side electrode portions,
the terminal electrode is substantially absent on a lower surface of the element body that is located on the opposite side of the upper surface of the element body along the third axis;
The element body has a reinforcing layer;
the reinforcing layer covers at least one of a pair of side surfaces facing each other in the first axis direction of the element body, the upper surface, and the lower surface;
the reinforcing layer comprises a filler and a matrix;
The filler is made of glass or alumina.
The filler has a needle-like, columnar or plate-like shape,
The particle size of the filler in the minor axis direction is 0.1 μm or more and 3.0 μm or less,
The particle size of the filler in the major axis direction is 0.5 μm or more and 15.0 μm or less,
The aspect ratio (%) of the filler, expressed as (particle diameter of the minor axis/particle diameter of the major axis)×100, is 0.7% or more and 60% or less,
A multilayer ceramic electronic component, wherein the content of the filler in the reinforcing layer is 30 volume % or more and 80 volume % or less. an element body in which internal electrode layers and insulating layers, which are substantially parallel to a plane including the first axis and the second axis, are alternately laminated along a third axis;
a terminal electrode formed in close contact with an outer surface of the element body and electrically connected to the internal electrode layer,
the terminal electrode has a pair of end-side electrode portions covering the end portions of the element body in the second axis direction from which the internal electrode layers are drawn out and facing each other in the second axis direction, and a pair of upper electrode portions each continuously covering a portion of an upper surface of the element body substantially perpendicular to the third axis, the pair of upper electrode portions being continuous with the end-side electrode portions,
The entire lower surface of the element body, which is located on the opposite side of the upper surface of the element body along the third axis, is exposed to the outside,
The element body has a reinforcing layer;
the reinforcing layer covers at least one of a pair of side surfaces facing each other in the first axis direction of the element body, the upper surface, and the lower surface;
the reinforcing layer comprises a filler and a matrix;
The filler is made of glass or alumina.
The filler has a needle-like, columnar or plate-like shape,
The particle size of the filler in the minor axis direction is 0.1 μm or more and 3.0 μm or less,
The particle size of the filler in the major axis direction is 0.5 μm or more and 15.0 μm or less,
The aspect ratio (%) of the filler, expressed as (particle diameter of the minor axis/particle diameter of the major axis)×100, is 0.7% or more and 60% or less,
A multilayer ceramic electronic component, wherein the content of the filler in the reinforcing layer is 30 volume % or more and 80 volume % or less. 8. The multilayer ceramic electronic component according to claim 6, further comprising the reinforcing layer covering the upper surface of the element body. 9. The multilayer ceramic electronic component according to claim 6, wherein the material of the substrate is at least one selected from the group consisting of glass and resin. 10. The multilayer ceramic electronic component according to claim 6, wherein the reinforcing layer covering the upper surface and the reinforcing layer covering the side surfaces continuously cover the element body. 11. The multilayer ceramic electronic component according to claim 6, wherein the reinforcing layer has a portion covering the lower surface, and an outer surface of the reinforcing layer covering the lower surface is a flat surface. 12. The multilayer ceramic electronic component according to claim 6 , wherein the material of the substrate is glass containing at least one of Si and Al as a main component. 13. The multilayer ceramic electronic component according to claim 6, wherein the filler is made of glass containing at least one auxiliary component selected from the group consisting of alkali metals, alkaline earth metals, transition metals and boron. 14. The multilayer ceramic electronic component according to claim 6, wherein outer surfaces of the end electrodes are covered with end covering layers. The outer surface of the end electrode portion is covered with an end covering layer,
15. The multilayer ceramic electronic component according to claim 1 , wherein a coverage rate, expressed as (covering area of said end covering layers/area of outer surfaces of said end electrode portions)×100, is 96 to 100%. The outer surface of the end electrode portion is covered with an end covering layer,
16. The multilayer ceramic electronic component according to claim 1, wherein the relative thickness of the end covering layers, expressed as (average thickness of the end covering layers/average thickness of the end electrode portions)×100, is 20 to 500%. The outer surface of the end electrode portion is covered with an end covering layer,
17. The multilayer ceramic electronic component according to claim 1, wherein the end covering layer is made of a film containing a resin as a main component. A multilayer ceramic electronic component as described in any one of claims 1 to 17, wherein the surface of an upper surface coating layer covering the upper surface of the element body located between a pair of upper electrode portions is in close contact with the surfaces of the upper electrode portions so as to be substantially flush with each other. The multilayer ceramic electronic component according to any one of claims 1 to 18 , wherein the lower surface of the element body is a flat surface. 20. The multilayer ceramic electronic component according to claim 1 , wherein the surface of the upper electrode portion is covered with at least one plating selected from the group consisting of Ni plating, Sn plating, Au plating and Cu plating. The multilayer ceramic electronic component according to any one of claims 1 to 20 , which can be embedded in a substrate.

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