JP6773114B2 - Ceramic electronic components - Google Patents

Description

The present invention relates to ceramic electronic components.

Examples of the ceramic electronic component in which the surface electrode is provided on the surface of the electronic component main body include a laminated ceramic electronic component such as a multilayer ceramic substrate.

In such ceramic electronic components, a coating called a so-called framing layer is used to prevent deterioration of the high frequency characteristics of the surface electrode, stress relaxation received by the surface electrode, and prevention of deterioration of resistance to plating erosion, that is, to improve the reliability of the surface electrode. A ceramic layer is provided on the outer peripheral portion of the surface electrode (see Patent Document 1).

Japanese Unexamined Patent Publication No. 2012-186269

The coated ceramic layer is provided not only on the outer peripheral portion of the surface electrode but also on the ceramic layer of the main body of the electronic component (hereinafter referred to as the base ceramic layer).
Usually, the coated ceramic layer is formed by placing a ceramic green sheet for forming a coated ceramic layer in a predetermined place and firing it, or by applying a ceramic paste for forming a coated ceramic layer in a predetermined place and firing it. It is said that it is preferably formed by firing at the same time as firing to obtain the main body of the electronic component and the surface electrode.

However, since the sinterability of the ceramic green sheet or the ceramic paste is different between the surface electrode and the base ceramic layer, there is a problem that the strength of the coated ceramic layer obtained after firing is different. Specifically, the strength of the coated ceramic layer on the surface electrode is lower than the strength of the coated ceramic layer on the base ceramic layer, and as a result, the coated ceramic layer formed by firing is peeled off from the surface electrode. There was a problem.

The present invention has been made to solve the above problems, and is a ceramic electronic component that has high bonding strength between the coated ceramic layer and the surface electrode and can prevent the coated ceramic layer from peeling from the surface electrode. The purpose is to provide.

It is considered that the cause of the difference in the strength of the coated ceramic layer obtained after firing is the difference in the sinterability of the base ceramic layer, the surface electrode and the coated ceramic layer.
Since the base ceramic layer and the coated ceramic layer are ceramics to each other, the sinterability is similar to each other, and it is considered that the coated ceramic layer formed on the base ceramic layer is unlikely to cause problems such as peeling. Be done. On the other hand, when the surface electrode and the coated ceramic layer are compared, the coated ceramic layer has a ceramic-rich composition, whereas the surface electrode has a metal-rich composition. It is considered that the sinterability is different from each other. That is, the present inventor considered that the difference in the sinterability between the surface electrode and the coated ceramic layer may reduce the bonding strength between the surface electrode and the coated ceramic layer, which may cause peeling.

Therefore, the present inventor has provided a coated ceramic formed on the surface electrode by providing an anchor layer having an intermediate property between the surface electrode and the coated ceramic layer between the coated ceramic layer on the surface electrode and the surface electrode. We have found that it is possible to improve the bonding strength of the layers and prevent the coating ceramic layer from peeling off, and completed the present invention.

The ceramic electronic component of the present invention includes an electronic component body having a base ceramic layer on its surface, a surface electrode provided on the surface of the electronic component body, and a coated ceramic layer covering the outer peripheral portion of the surface electrode. It is a ceramic electronic component, and is characterized in that an anchor layer containing both a metal component and a ceramic component is provided between the outer peripheral portion of the surface electrode and the coated ceramic layer.

The ceramic electronic component of the present invention is provided with an anchor layer having both a metal component and a ceramic component on the outer peripheral portion of the surface electrode, so that the bonding strength between the coated ceramic layer and the anchor layer is increased between the coated ceramic layer and the surface. It is higher than the bonding strength with the electrode. As a result, when the ceramic electronic component is fired, the coated ceramic layer is less likely to peel off.

Further, if the bonding strength between the coated ceramic layer and the anchor layer is high, even when the plated layer is formed after the coated ceramic layer is formed, the surface electrode and the coated ceramic layer before the plating layer is formed Since the plating solution is less likely to enter during the period, the risk of abnormal precipitation is reduced.

Since the anchor layer contains both a metal component and a ceramic component, the ceramic component of the anchor layer is sintered with the coated ceramic layer in the vicinity of the boundary between the anchor layer and the coated ceramic layer. Further, in the vicinity of the boundary between the anchor layer and the surface electrode, the metal component of the anchor layer is sintered with the surface electrode. That is, in the vicinity of each boundary, only one of the metal component or the ceramic component in the anchor layer preferentially causes the sintering reaction, so that the vicinity of the boundary between the anchor layer and the coated ceramic layer and the vicinity of the boundary between the anchor layer and the surface electrode A physical anchor structure is formed in the above, and the anchor layer, the coated ceramic layer, the anchor layer, and the surface electrode are firmly bonded to each other.
Further, since the anchor layer contains both the metal component and the ceramic component, the sintering start temperature of the ceramic component in the anchor layer is reached even if the original sintering start temperature of the metal component in the anchor layer is exceeded. Sintering does not start until. Therefore, the low melting point component (also referred to as the liquid phase component) in the coated ceramic layer melts first, and sintering proceeds while infiltrating into the anchor layer. At this time, the liquid phase component penetrates into the anchor layer and sintering proceeds, so that a physical anchor structure is formed near the boundary between the coated ceramic layer and the anchor layer, and the coated ceramic layer and the anchor layer are strengthened. Is joined to.

In the ceramic electronic component of the present invention, the anchor layer is preferably provided only between the outer peripheral portion of the surface electrode and the coated ceramic layer.
If the anchor layer is provided only between the outer peripheral portion of the surface electrode and the coated ceramic layer, the surface electrode is exposed at the portion of the surface electrode where the coated ceramic layer is not provided. , The plating property of the surface electrode does not deteriorate. Therefore, it is possible to suppress a decrease in the plating property of the surface electrode while maintaining the bonding strength of the coated ceramic layer.

In the ceramic electronic component of the present invention, it is preferable that the metal component and the ceramic component constituting the anchor layer contain the same components as the metal component constituting the surface electrode and the ceramic component constituting the coated ceramic layer, respectively. ..
When the metal component constituting the anchor layer contains the same component as the metal component constituting the surface electrode, the reactivity between the anchor layer and the surface electrode is improved, and the bonding strength is improved. Further, when the ceramic component constituting the anchor layer contains the same component as the ceramic component constituting the coated ceramic layer, the reactivity between the anchor layer and the coated ceramic layer is improved, and the bonding strength is improved. Therefore, when the metal component and the ceramic component constituting the anchor layer contain the same components as the metal component constituting the surface electrode and the ceramic component constituting the coated ceramic layer, respectively, the bonding strength between the surface electrode and the coated ceramic layer Can be improved and peeling can be further suppressed.

In the ceramic electronic component of the present invention, the ratio of the volume of the metal component to the total volume of the metal component and the ceramic component constituting the anchor layer is preferably 10% or more and 90% or less.
When the ratio of the volume of the metal component to the total volume of the metal component and the ceramic component constituting the anchor layer is 10% or more and 90% or less, the anchor layer is sufficient for both the surface electrode and the coated ceramic layer. It will have a good bonding strength.

According to the present invention, it is possible to provide a ceramic electronic component having high bonding strength between the coated ceramic layer and the surface electrode and capable of preventing peeling of the coated ceramic layer from the surface electrode.

FIG. 1 is a cross-sectional view schematically showing an example of the ceramic electronic component of the present invention. 2A to 2B are cross-sectional views schematically showing an example of a method for manufacturing the ceramic electronic component 1 shown in FIG. 1. FIG. 3 is a cross-sectional view schematically showing another example of the ceramic electronic component of the present invention.

Hereinafter, the ceramic electronic component of the present invention will be described.
However, the present invention is not limited to the following configurations, and can be appropriately modified and applied without changing the gist of the present invention.
A combination of two or more of the individual desirable configurations of the invention described below is also the invention.

In the following embodiment, a case where the ceramic electronic component is a laminated ceramic electronic component such as a multilayer ceramic substrate, that is, a case where the electronic component main body has a laminated structure in which a plurality of ceramic layers are laminated will be described. However, the present invention is not limited to laminated ceramic electronic components, and is applicable to various ceramic electronic components in which the electronic component body has a base ceramic layer on the surface and surface electrodes are provided on the surface of the electronic component body. It is possible to do.

FIG. 1 is a cross-sectional view schematically showing an example of the ceramic electronic component of the present invention.
Although the overall configuration is not shown in FIG. 1, the ceramic electronic component 1 includes an electronic component main body 10 having a base ceramic layer 11 on its surface, and a surface electrode 20 provided on the surface of the electronic component main body 10. A coated ceramic layer 40 that covers the outer peripheral portion of the surface electrode 20 is provided.
The anchor layer 30 is provided between the outer peripheral portion of the surface electrode 20 (the region indicated by the double-headed arrow W1 in FIG. 1) and the coating ceramic layer 40. As shown in FIG. 1, the outer peripheral portion of the surface electrode 20 is covered with a coated ceramic layer 40. The region of the surface electrode 20 that is not the outer peripheral portion is defined as the central portion (the region indicated by the double-headed arrow W2 in FIG. 1).

In FIG. 1, the electronic component main body 10 has a laminated structure in which a plurality of base material ceramic layers 11 are laminated, and inside the electronic component main body 10, an internal conductor film 12 as an internal wiring conductor and a via hole conductor are provided. 13 is provided. The inner conductor film 12 is electrically connected to the via hole conductor 13, and the via hole conductor 13 is electrically connected to the surface electrode 20.

In the present specification, the surface electrode is coated with the coated ceramic layer even when the anchor layer is arranged on the upper surface of the surface electrode and the coated ceramic layer is arranged on the surface electrode via the anchor layer. That is.

The base material ceramic layer constituting the electronic component body preferably contains a low-temperature sintered ceramic material.
The low-temperature sintered ceramic material means a ceramic material that can be sintered at a temperature of 1000 ° C. or lower and can be co-fired with Ag or Cu at the same time.

Examples of the low-temperature sintered ceramic material contained in the base ceramic layer include a glass composite low-temperature sintered ceramic material obtained by mixing borosilicate glass with a ceramic material such as quartz, alumina, and forsterite, ZnO-MgO-. Al ₂ O ₃ -SiO ₂ -based crystallized glass crystallized glass-based low-temperature co-fired ceramic material with a, _BaO-Al 2 O 3 -SiO ₂ -based ceramic material and _{Al 2 O 3 -CaO-SiO 2} -MgO- Examples thereof include non-glass low-temperature sintered ceramic materials using B ₂ O ₃ ceramic materials and the like.

The internal wiring conductors (internal conductor film and via hole conductor) provided inside the main body of the electronic component contain a conductive component. As the conductive component contained in the internal wiring conductor, for example, Au, Ag, Cu, Pt, Ta, W, Ni, Fe, Cr, Mo, Ti, Pd, Ru and one of these metals are the main components. Examples include alloys. The internal wiring conductor preferably contains Au, Ag or Cu as a conductive component, and more preferably contains Ag or Cu. Since Au, Ag and Cu have low resistance, they are particularly suitable when ceramic electronic components are used for high frequency applications.

The surface electrodes provided on the surface of the electronic component body are for connecting to other electronic components such as wiring boards or mounted components. The surface electrode and other electronic components are connected by soldering or the like.

As the conductive component contained in the surface electrode, for example, Au, Ag, Cu, Pt, Ta, W, Ni, Fe, Cr, Mo, Ti, Pd, Ru and one of these metals are the main components. Examples include alloys. The surface electrode preferably contains the same conductive component as the internal wiring conductor, and specifically, the surface electrode preferably contains Au, Ag, or Cu as the conductive component, and more preferably contains Ag or Cu.

The width of the outer peripheral portion of the surface electrode (the length represented by W1 in FIG. 1) is not particularly limited, but is preferably 40 μm or more and 100 μm or less.

The surface electrode may have a one-layer structure or a multi-layer structure, but it is preferable that the surface electrode has a multi-layer structure.
When the surface electrode has a one-layer structure, it is preferably composed of only a sintered layer.
The sintered layer is formed by simultaneously firing the conductive paste together with the base ceramic layer, the anchor layer, and the coated ceramic layer.

Hereinafter, the sintered layer of the surface electrode will be described.
The sintered layer constituting the surface electrode contains a conductive component. The sintered layer may further contain a metal oxide in order to increase the bonding strength with the electronic component body.
When the sintered layer has a multi-layer structure, the first sintered layer provided on the upper surface of the base ceramic layer located on the surface of the electronic component body and the second baked layer provided on the upper surface of the first sintered layer. It is more preferable to have at least a two-layer structure including a layer.

As the conductive component contained in the first sintered layer, for example, Au, Ag, Cu, Pt, Ta, W, Ni, Fe, Cr, Mo, Ti, Pd, Ru and one of these metals are mainly used. Examples thereof include alloys as components. The first sintered layer preferably contains the same conductive component as the internal wiring conductor, and specifically, preferably contains Au, Ag or Cu as the conductive component, and may contain Ag or Cu. More preferred.

Examples of the metal oxide contained in the first sintered layer include those containing at least one metal element selected from the group consisting of Al, Zr, Ti, Si, and Mg. The metal oxide may be one kind or two or more kinds. Among these, those containing at least one metal element selected from the group consisting of Al, Zr and Ti are preferable, and metal oxides containing Al are more preferable.

The content of the metal oxide in the first sintered layer is not particularly limited, but is preferably higher than the content of the metal oxide in the second sintered layer. Specifically, the content of the metal oxide in the first sintered layer is preferably 1% by weight or more, more preferably 3% by weight or more. On the other hand, the content of the metal oxide in the first sintered layer is preferably less than 10% by weight, more preferably less than 5% by weight.

When the first sintered layer contains a metal oxide, the metal particles constituting the conductive component and the metal oxide particles may be dispersed and exist, and the metal oxide may be present around the metal particles. Although it may be coated, it is preferable that the metal oxide is coated around the metal particles. When the metal oxide is coated around the metal particles, the bonding strength with the electronic component body can be increased even if the content of the metal oxide is small.

The plan-view shape of the first sintered layer is not particularly limited, and examples thereof include a quadrangle including a rectangle, a polygon other than the quadrangle, a circle, and an ellipse.

The second sintered layer constituting the surface electrode contains a conductive component. The conductive component contained in the second sintered layer is preferably the same as the conductive component contained in the first sintered layer.

The second sintered layer may contain the same metal oxide as the metal oxide contained in the first sintered layer, but when the content of the metal oxide increases, the upper surface of the second sintered layer It becomes difficult for plating to adhere to. Therefore, the second sintered layer preferably contains less metal oxide than the first sintered layer, and more preferably does not substantially contain the metal oxide. When the second sintered layer contains a metal oxide and the content of the metal oxide in the first sintered layer is 1% by weight or more and less than 10% by weight, the metal in the second sintered layer The oxide content is preferably less than 1% by weight. When the content of the metal oxide in the first sintered layer is 3% by weight or more and less than 5% by weight, the content of the metal oxide in the second sintered layer is less than 3% by weight. Is preferable.

It is preferable that the area of the upper surface of the second sintered layer is substantially the same as the area of the upper surface of the first sintered layer. That is, it is preferable that the plan view shape of the second sintered layer is substantially the same as the plan view shape of the first sintered layer.

The number of sintered layers is not limited to two, and there is another layer between the first sintered layer provided on the upper surface of the base ceramic layer and the second sintered layer provided on the upper surface. A sintered layer may be provided.

Subsequently, the anchor layer provided on the surface electrode will be described.
The anchor layer is a layer having both a metal component and a ceramic component, and a paste material containing the metal component and the ceramic component is formed on the upper surface of the surface electrode or the upper surface of the conductive paste film serving as the surface electrode and fired. Obtained by doing.

The metal components constituting the anchor layer are not particularly limited, but are mainly composed of Au, Ag, Cu, Pt, Ta, W, Ni, Fe, Cr, Mo, Ti, Pd, Ru and one of these metals. Examples thereof include alloys, which preferably contain the same components as the metal components constituting the surface electrode, and more preferably the metal components constituting the anchor layer and the metal components constituting the surface electrode are the same. When the surface electrode has a multi-layer structure, the metal component constituting the anchor layer preferably contains the same component as the metal component constituting the outermost (closer to the anchor layer) sintered layer, and the anchor. It is more preferable that the metal component constituting the layer and the metal component constituting the outermost sintered layer (the side closer to the anchor layer) are the same.

The ceramic component constituting the anchor layer is not particularly limited, but preferably contains the same component as the ceramic component constituting the coated ceramic layer, and the ceramic component constituting the anchor layer and the ceramic component constituting the coated ceramic layer are the same. Is more preferable.
Since the anchor layer has both a metal component and a ceramic component, good bonding strength can be maintained regardless of whether the anchor layer is bonded to the surface electrode or the coated ceramic layer.

The ratio of the metal component and the ceramic component constituting the anchor layer is not particularly limited, but the ratio of the volume of the metal component to the total volume of the metal component and the ceramic component is preferably 5% or more and 95% or less. It is more preferably% or more and 90% or less, and further preferably 40% or more and 60% or less.
When the ratio of the volume of the metal component to the total volume of the metal component and the ceramic component is 5% or more and 95% or less, the anchor layer can be bonded to the surface electrode and the coated ceramic layer.

The metal component and the ceramic component constituting the anchor layer may be dispersedly present in the anchor layer, or may be in a form in which the ceramic component covers the periphery of the metal component.

The thickness of the anchor layer is not particularly limited, but is preferably 5 μm or more and 10 μm or less.

The anchor layer may be formed over the entire surface electrode, but is preferably formed only on the outer peripheral portion of the surface electrode. That is, it is preferable that the anchor layer is not provided in the central portion of the surface electrode, but is provided only between the outer peripheral portion of the surface electrode and the coated ceramic layer.
When a plating layer is further formed on the surface electrode, if an anchor layer is provided at the center of the surface electrode, the plating property is lowered.

The coated ceramic layer that covers the outer peripheral portion of the surface electrode is provided on the base ceramic layer located on the surface of the electronic component body and on the surface electrode. Since the anchor layer described above is arranged on the surface electrode, the coated ceramic layer provided on the surface electrode is provided on the surface electrode via the anchor layer.

The coated ceramic layer preferably contains a low temperature sintered ceramic material. In this case, the low-temperature sintered ceramic material contained in the coated ceramic layer may be the same as or different from the low-temperature sintered ceramic material contained in the base ceramic layer, but is contained in the base ceramic layer. It is preferably the same as the low temperature sintered ceramic material.

The thickness of the coated ceramic layer formed on the anchor layer is not particularly limited, but is preferably 2 μm or more and 20 μm or less.
When the thickness of the coated ceramic layer formed on the anchor layer varies, the coated ceramic layer obtained from the area of the outer peripheral portion where the coated ceramic layer is formed and the volume of the coated ceramic layer existing on the outer peripheral portion. Let the average thickness of the coating ceramic layer be the thickness of the coated ceramic layer formed on the anchor layer.

A plating layer may be further formed on the surface of the surface electrode.
The plating layer is formed by subjecting a surface electrode to electrolytic plating or electroless plating. Since the plating layer is usually formed after forming the sintered layer, the anchor layer and the coating ceramic layer, the plating layer is not coated by the coating ceramic layer.

The plating layer is preferably made of Au, Ag, Ni, Pd, Cu, Sn or an alloy containing these metals. The plating layer is a Ni / Au plating layer in which the first layer is Ni from the surface electrode side and the second layer is Au, a Ni / Sn plating layer in which the first layer is Ni from the surface electrode side and the second layer is Sn. The first layer from the surface electrode side may be a plating layer composed of a plurality of layers such as a Ni / Pd / Au plating layer in which the first layer is Ni and the second layer is Pd and the third layer is Au.

The thickness of the plating layer is not particularly limited, but is preferably 1 μm or more and 10 μm or less.

The ceramic electronic component 1 shown in FIG. 1 is preferably manufactured as follows.
2A to 2B are cross-sectional views schematically showing an example of a method for manufacturing the ceramic electronic component 1 shown in FIG. 1.

First, the unsintered laminate 100 shown in FIG. 2A is produced.
In order to prepare the unsintered laminate 100, a plurality of base material ceramic green sheets 111 are prepared. The base material ceramic green sheet 111 becomes the base material ceramic layer 11 after firing.

The base material ceramic green sheet is obtained by molding a slurry containing a powder of a ceramic raw material such as a low-temperature sintered ceramic material, an organic binder and a solvent into a sheet by a doctor blade method or the like. The slurry may contain various additives such as a dispersant and a plasticizer.

As the organic binder contained in the slurry, for example, butyral resin (polyvinyl butyral), acrylic resin, methacrylic resin and the like can be used. As the solvent, for example, alcohols such as toluene and isopropyl alcohol can be used. As the plasticizer, for example, di-n-butylphthalate or the like can be used.

Next, a through hole for the via hole conductor 13 is formed in the specific base material ceramic green sheet 111. By filling the through holes with a conductive paste containing, for example, Ag or Cu as a conductive component, a conductive paste body 113 to be a via hole conductor 13 is formed.

Further, using a conductive paste having the same composition as the above-mentioned conductive paste, a conductive paste film 112 to be an internal conductor film 12 is formed on a specific base material ceramic green sheet 111 by a method such as screen printing. ..

Further, a conductive paste film 120 to be a surface electrode 20 is formed on the base material ceramic green sheet 111 arranged on the surface after lamination by firing. The conductive paste film 120 that should become the surface electrode 20 by firing can be formed by a method such as screen printing using, for example, a conductive paste containing Ag or Cu as a conductive component. The conductive paste film 120 that should become the surface electrode 20 by firing may be formed after laminating the base ceramic green sheet 111 and before firing.

When the surface electrode has a multi-layer structure, a conductive paste film to be the second sintered layer is formed on the conductive paste film to be the first sintered layer by a method such as screen printing. can do.

After that, the anchor layer paste film 130 to be the anchor layer 30 is formed only on the outer peripheral portion of the conductive paste film 120 to be the surface electrode 20 by firing. The anchor layer paste film 130 is an anchor layer paste in which a powder of a ceramic raw material such as a low-temperature sintered ceramic material and a powder containing Ag or Cu as a conductive component are dispersed in a mixture of an organic binder and a solvent. Alternatively, it can be formed by a method such as screen printing using an anchor layer paste in which ceramic coated metal particles having a ceramic coating on the surface of Ag or Cu, which is a conductive component, dispersed in a mixture of an organic binder and a solvent. it can.

Separately, a coated ceramic green sheet 140 is prepared. The coated ceramic green sheet 140 becomes a coated ceramic layer 40 after firing.

The coated ceramic green sheet is obtained by molding a slurry containing a powder of a ceramic raw material such as a low-temperature sintered ceramic material, an organic binder and a solvent into a sheet by a doctor blade method or the like. The slurry may contain various additives such as a dispersant and a plasticizer. As the slurry for producing the coated ceramic green sheet, the slurry for producing the base ceramic green sheet can also be used.

Subsequently, the base material ceramic green sheet 111 on which the conductive paste body 113 to be the via hole conductor 13 or the conductive paste film 112 to be the internal conductor film 12 is formed, and the conductive paste to be the surface electrode 20 by firing. The base ceramic green sheet 111 on which the film 120 is formed and the coated ceramic green sheet 140 are laminated and pressure-bonded to produce an unsintered laminated body 100. The coated ceramic green sheet 140 is arranged on the base ceramic green sheet 111 arranged on the surface after lamination and on the anchor layer paste film 130 which should be the anchor layer 30.

Instead of the coated ceramic green sheet 140, the paste-like composition is placed on the base ceramic green sheet 111 located on the surface of the unsintered laminate 100 and on the anchor layer paste film 130 to be the anchor layer 30. The unsintered laminate 100 can also be produced by applying to. In this case, the paste-like composition may be applied on the base material ceramic green sheet 111 before laminating and on the anchor layer paste film 130 to be the anchor layer 30.

Then, the unsintered laminate 100 is fired. As a result, as shown in FIG. 2B, the electronic component main body 10 having the base ceramic layer 11 on the surface, the surface electrode 20 provided on the surface of the base ceramic layer 11, and the outer peripheral portion of the surface electrode 20 are covered. A ceramic electronic component 1 which is a laminated body including a coated ceramic layer 40 and an anchor layer 30 provided between the surface electrode 20 and the coated ceramic layer 40 can be obtained.

The surface electrode can also be formed by forming a conductive paste film on the surface of the main body of the electronic component after sintering and firing it. The anchor layer can also be formed by forming an anchor layer paste film on the surface of the surface electrode after sintering and firing it. Further, the coated ceramic layer can also be formed by arranging the coated ceramic green sheet on the anchor layer after sintering and firing the coated ceramic green sheet. However, it is preferable that the surface electrode, the anchor layer and the coated ceramic layer are fired at the same time as the electronic component body by firing to obtain the electronic component body to obtain the ceramic electronic component. It is advantageous to bake the surface electrode, the anchor layer and the coated ceramic layer at the same time as the electronic component body to improve the efficiency and cost of the manufacturing process, and to join the electronic component body and the surface electrode. The strength, the bonding strength between the surface electrode and the anchor layer, the bonding strength between the anchor layer and the coating ceramic layer, and the bonding strength between the electronic component body and the coating ceramic layer can be increased. When the surface electrode, the anchor layer and the coated ceramic layer are formed by simultaneous firing, the base material ceramic layer constituting the electronic component body preferably contains a low-temperature sintered ceramic material as described above.

Further, a restraint green sheet containing a metal oxide (Al ₂ O _3, etc.) as a main component, which is not substantially sintered at the sintering temperature of the unsintered laminate 100, is prepared, and the unsintered laminate 100 is prepared. The unsintered laminate 100 may be fired with the restraint green sheet arranged on the outermost surface. In this case, the restraint green sheet does not substantially sinter during firing, so that shrinkage does not occur, and the restraint green sheet acts to suppress shrinkage in the main surface direction with respect to the laminated body.

In the ceramic electronic component of the present invention, an anchor layer is arranged between the outer peripheral portion of the surface electrode and the coated ceramic layer. As a result, the sinterability of the coated ceramic layer on the surface electrode is improved, and the bonding strength between the coated ceramic layer and the surface electrode is increased. Therefore, when the ceramic electronic component is fired, the coated ceramic layer becomes the surface electrode. It becomes difficult to peel off from.

FIG. 3 is a cross-sectional view schematically showing another example of the ceramic electronic component of the present invention.
In the ceramic electronic component 2 shown in FIG. 3, the anchor layer 30 is not formed over the entire surface electrode 20, but is provided only between the outer peripheral portion of the surface electrode 20 and the coated ceramic layer 40. Therefore, when the plating layer is formed on the surface electrode 20, the plating property does not deteriorate.

Hereinafter, examples in which the ceramic electronic component of the present invention is disclosed more specifically will be shown. The present invention is not limited to these examples.

[Confirmation of effect by anchor layer]
According to the method described with reference to FIGS. 2A and 2B, a surface electrode provided on the surface of the base material ceramic layer and a coated ceramic layer covering the outer peripheral portion of the surface electrode are provided, and an anchor layer is arranged on the surface electrode. The ceramic electronic components 1-1 to 1-2 were produced.
Ceramic electronic components 1-1 are those in which the anchor layer is arranged over the entire surface electrode, and all are the same as ceramic electronic components 1-1 except that the anchor layer is arranged only between the outer peripheral portion of the surface electrode and the coated ceramic layer. The ceramic electronic component 1-2 was used. Further, the ceramic electronic component 1-3 in which the coating ceramic layer was directly arranged on the outer peripheral portion of the surface electrode without arranging the anchor layer was used.
For each of 1000 ceramic electronic parts, the cross section of the ceramic electronic parts after firing is observed, and it is visually determined whether or not the coated ceramic layer is peeled from the surface electrode, and the ratio of those in which peeling does not occur (non-defective rate). ) Was judged. Good product rate of 90% or more is ◎ (excellent: peeling is extremely difficult to occur), 80% or more and less than 90% is ○ (good: peeling is difficult to occur), 60% or more and less than 80% is △ ( Possible: Some peeling was observed), and those less than 60% were evaluated as x (defective: easy peeling). The results are shown in Table 1.

From Table 1, it was confirmed that by arranging the anchor layer on the surface electrode, the peeling of the coated ceramic layer could be significantly suppressed and the bonding strength between the coated ceramic layer and the surface electrode was enhanced. It was.
Further, it was confirmed that it is not essential to provide the anchor layer over the entire surface electrode, and that a sufficient effect is exhibited by providing the anchor layer only between the outer peripheral portion of the surface electrode and the coated ceramic layer.

[Confirmation of effect by composition of anchor layer]
Ceramic electronic components 1-4 to 1-9 in which the composition of the surface electrode and the anchor layer are changed are produced from the ceramic electronic component 1-1, and the non-defective rate is evaluated by the same method as in [Confirmation of effect by anchor layer]. did.
Table 2 shows the composition of the surface electrode, the anchor layer and the coated ceramic layer, and the evaluation results of the non-defective rate.

From Table 2, in the ceramic electronic components 1-1 and 1-4 to 1-7, the ratio of the volume of the metal component to the total volume of the metal component and the ceramic component constituting the anchor layer is 10% or more and 90% or less. It was confirmed that the non-defective product rate was ○ (good) or higher, and the peeling of the coated ceramic layer was further suppressed. Further, by comparing the ceramic electronic parts 1-1 and 1-6 to 1-7, when the metal component of the anchor layer and the metal component of the surface electrode are the same, and when the ceramic component of the anchor layer and the coating ceramic layer are used. It was confirmed that the peeling of the coated ceramic layer was further suppressed when the ceramic components were the same.

1, 2 Ceramic electronic component 10 Electronic component body 11 Base material Ceramic layer 20 Surface electrode 30 Anchor layer 40 Coated ceramic layer W1 Outer peripheral part of surface electrode W2 Central part of surface electrode

Claims (12)

A ceramic electronic component including an electronic component body having a base ceramic layer on its surface, a surface electrode provided on the surface of the electronic component body, and a coated ceramic layer covering the outer peripheral portion of the surface electrode.
An anchor layer containing both a metal component and a ceramic component is provided between the outer peripheral portion of the surface electrode and the coating ceramic layer .
A ceramic electronic component characterized in that the metal component and the ceramic component constituting the anchor layer contain the same components as the metal component constituting the surface electrode and the ceramic component constituting the coated ceramic layer, respectively . The ceramic electronic component according to claim 1, wherein the metal component and the ceramic component constituting the anchor layer are dispersed and exist in the anchor layer, respectively. The ceramic electronic component according to claim 1, wherein the metal component and the ceramic component constituting the anchor layer are such that the ceramic component covers the periphery of the metal component. The ceramic electronic component according to any one of claims 1 to 3, wherein the thickness of the anchor layer is 5 μm or more and 10 μm or less. The ceramic electronic component according to any one of claims 1 to 4, wherein the coated ceramic layer contains a low-temperature sintered ceramic material. The base material ceramic layer contains a low temperature sintered ceramic material and contains.
The ceramic electronic component according to claim 5, wherein the low-temperature sintered ceramic material contained in the coated ceramic layer is the same as the low-temperature sintered ceramic material constituting the base material ceramic layer. The surface electrode has at least a two-layer structure including a first sintered layer provided on the upper surface of the electronic component and a second sintered layer provided on the upper surface of the first sintered layer. The ceramic electronic component according to any one of claims 1 to 6, wherein the content of the metal oxide in the first sintered layer is higher than the content of the metal oxide in the second sintered layer. The ceramic electronic component according to claim 7, wherein the metal particles and the metal oxide particles constituting the conductive component in the first sintered layer are dispersed and exist. The ceramic electronic component according to claim 7, wherein a metal oxide is coated around the metal particles in the first sintered layer. The ceramic according to any one of claims 7 to 9, wherein the conductive component contained in the first sintered layer of the surface electrode and the conductive component contained in the second sintered layer of the surface electrode are the same. Electronic components. The ceramic electronic component according to any one of claims 1 to 10, wherein the anchor layer is provided only between the outer peripheral portion of the surface electrode and the coated ceramic layer. Ratio of the volume of the metal component to the total volume of the metal component and a ceramic component constituting the anchor layer is preferably 10% or more, 90% or less, a ceramic electronic component according to any one of claims 1 to 11 ..

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