KR20120042812A - Capacitor and method for manufacturing the same - Google Patents

Abstract

PURPOSE: A condenser and a manufacturing method thereof are provided to obtain good insertion loss characteristics by multiplying an electrode cross-section of a connection part and a ground terminal of an inner electrode. CONSTITUTION: A condenser(1) comprises a condenser body(10) consisting of a dielectric, a first inner electrode, and a second inner electrode(12). The condenser comprises a first signal terminal(15), a second signal terminal(16), and a ground terminal(17). The first signal terminal and the second signal terminal are connected to the first inner electrode. The ground terminal is formed in order to be connected to the second inner electrode of the outer surface of the condenser body. The ground terminal is connected to a ground potential. The ground terminal has a plating layer(17a) which is formed on the condenser body in order to be connected to the second inner electrode.

Description

Capacitor and Method of Manufacturing the Same {CAPACITOR AND METHOD FOR MANUFACTURING THE SAME}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a capacitor and a method of manufacturing the same, and more particularly, to a capacitor including a pair of signal terminals, a ground terminal, and a method of manufacturing the same.

Conventionally, the 3-terminal type capacitor | condenser described in patent document 1 etc. is known, for example. Three-terminal capacitors generally contain a rectangular ceramic body. First and second internal electrodes are provided inside the ceramic body. The first internal electrode and the second internal electrode are disposed to face each other. First and second signal terminals are formed on both end surfaces of the ceramic element. The first and second signal terminals are connected to the first internal electrode. On the other hand, a part of the side surface of the ceramic element is formed with a ground terminal connected to the second internal electrode and connected to the ground potential.

Each of the first and second signal terminals and the ground terminal is generally composed of a fired film formed on a ceramic body and one or a plurality of plated films formed on the fired film.

Japanese Unexamined Patent Publication No. 2000-107658

The fired film of the external electrode terminal is formed by mechanically positioning the ceramic element and applying the conductive paste, and then firing the conductive paste. The mechanical application of the conductive paste with high positional accuracy accurately takes into account the dimensional error of the machine. Very difficult. For this reason, it is necessary to form an external electrode terminal larger than the exposed part of an internal electrode so that the exposed part of an internal electrode may be reliably covered by an electrode terminal. That is, the exposed portion of the internal electrode needs to be smaller than the external electrode terminal.

In this way, when the external electrode terminal has a fired film, it is necessary to reduce the exposed portion of the internal electrode. For this reason, there exists a tendency for the electrode cross-sectional area of the connection part of the 2nd internal electrode to the ground terminal to become small. When the electrode cross-sectional area of the connection portion with the ground terminal of the second internal electrode is small, there is a problem that the ESL becomes large and the noise canceling characteristic deteriorates. In other words, there is a problem that the insertion loss characteristics deteriorate.

The present invention has been made in view of this point, and an object thereof is to provide a capacitor having a good insertion loss characteristic and a method of manufacturing the same.

The capacitor according to the present invention includes a rectangular parallelepiped capacitor body, a first internal electrode, a second internal electrode, first and second signal terminals, and a ground terminal. The capacitor body is made of a dielectric. The capacitor body has first and second main surfaces, first and second side surfaces, and first and second cross sections. The first and second main surfaces extend along the longitudinal direction and the width direction. Sides of the first and second sides extend along the longitudinal direction and the height direction. The first and second cross sections extend along the width direction and the height direction. The first internal electrode is formed inside the capacitor body. The second internal electrode is formed inside the capacitor body. The second internal electrode faces the first internal electrode. The first signal terminal is formed in the first cross section. The first signal terminal is connected to the first internal electrode. The second signal terminal is formed in the second cross section. The second signal terminal is connected to the first internal electrode. The ground terminal is formed to be connected to the second internal electrode on a portion of the first side surface. The ground terminal is connected to ground potential. The ground terminal has one or a plurality of plating films. One or a plurality of plating films are formed on the capacitor body. One or more plating films are directly connected to the second internal electrode.

In one particular aspect of the capacitor according to the present invention, the one or the plurality of plating films is a wet plating film formed by wet plating. According to this structure, the damage to a capacitor | condenser main body can be reduced compared with the electroless plating which uses a chemical solvent.

In another particular aspect of the condenser according to the invention, the condenser is a noise filter.

In another particular aspect of the condenser according to the invention, the signal terminal is connected to a static potential. In this case, the ground terminal is at the ground potential side. For this reason, even if moisture enters into the capacitor | condenser main body from the part in which the ground terminal is formed, the metal component contained in a ground terminal does not ionize. Therefore, the fall of the reliability of the capacitor | condenser resulting from ionization of the metal contained in a ground terminal can be suppressed effectively.

In another particular aspect of the capacitor according to the present invention, the ground terminal does not include a plastic conductive film. In this case, the positional accuracy of the ground terminal can be easily improved.

In another particular aspect of the condenser according to the invention, the signal terminal is formed on an outer surface of the condenser body, and is formed on one or a plurality of plating films directly connected to the first internal electrode and on one or a plurality of plating films. It has a plastic conductive film containing a glass component. According to this structure, the fall of the reliability of a capacitor | condenser can be suppressed more effectively.

In another specific aspect of the capacitor according to the present invention, each of the first and second signal terminals is formed on an outer surface of the capacitor body and contains a plastic conductive film containing a glass component directly connected to the first internal electrode. And one or a plurality of plating films formed on the plastic conductive film. In this structure, since the glass component is contained in the plastic conductive film, the ingress of moisture into the capacitor body is effectively suppressed from the portion where the first and second signal terminals of the capacitor body are formed. In addition, the adhesion to the condenser body is increased. Therefore, the fall of the reliability of the capacitor | condenser resulting from ionization of the metal contained in a 1st and 2nd signal terminal can be suppressed effectively.

In another specific aspect of the capacitor according to the present invention, the plastic conductive film includes Cu.

In another particular aspect of the condenser according to the invention, the ground terminal has portions formed on the first and second main surfaces, and the second internal electrode faces the first internal electrode in the height direction. An opposing portion, and a connecting portion for connecting the opposing portion and the ground terminal, wherein the capacitor includes a connection portion of the second internal electrode in the height direction and a portion located on the first or second main surface of the ground terminal. It is arrange | positioned between and further includes the ground dummy electrode connected to the ground terminal. According to this structure, when soldering to a substrate, all solder-wetted areas of the solder can be formed at once from the first main surface to the second main surface on the side surface by plating.

In another specific aspect of the capacitor according to the present invention, the plated film connected to the second internal electrode is made of a Cu plated film containing Cu. According to this structure, plating becomes easy to form in a ceramic element.

In another specific aspect of the capacitor according to the present invention, the ground terminal is formed on a Cu plated film and formed on a Ni plated film containing Ni, and a Sn plated film formed on a Ni plated film and containing Sn. Have more. According to this configuration, the bonding strength to the solder can be increased.

In another particular aspect of the capacitor according to the invention, the first and second internal electrodes are made of Ni. According to this structure, manufacturing cost can be reduced compared with the case where 1st and 2nd internal electrodes are formed by Pd and Ag / Pd, for example.

The method for manufacturing a capacitor according to the present invention is a method for manufacturing the capacitor of the present invention. The manufacturing method of the capacitor | condenser which concerns on this invention is the process of printing the 1st internal electrode formation conductive paste on a dielectric sheet, and obtaining the 1st sheet | seat in which the 1st internal electrode formation conductive film was formed, and the 2nd Printing a conductive paste for forming an internal electrode on a dielectric sheet and obtaining a second sheet having a conductive film for forming a second internal electrode; and printing a first sheet, a second sheet, and a conductive paste. Applying a conductive paste for applying a conductive paste so as to contact the conductive film for forming the first internal electrode on the laminate, a step of forming a laminate by laminating undiluted dielectric sheets, a baking step of firing the laminate, and a laminate And a baking step of baking the coated conductive paste to form a fired film, and one or more platings on the laminate so as to contact the conductive film for forming the second internal electrode. A plating film forming step of forming a film, and an alloying step of alloying the plating film and the conductive film for forming the second internal electrode at the interface between the plating film and the conductive film for forming the second internal electrode by heating the laminate. It is included. In the manufacturing method according to the present invention, the plating film and the conductive film for forming the second internal electrode are alloyed at the interface between the plating film and the conductive film for forming the second internal electrode. For this reason, the high connection strength of a 2nd internal electrode and a plating film can be implement | achieved. Therefore, a highly reliable capacitor can be manufactured.

In one specific aspect of the manufacturing method of the capacitor according to the present invention, the conductive paste coating step, the baking step, the plating film forming step, and the alloying step are performed in this order.

In another specific aspect of the manufacturing method of the capacitor according to the present invention, the plating film forming step is performed prior to the baking step, the conductive paste coating step is performed after the plating forming step, and the baking step and the alloying step are performed simultaneously after the conductive paste coating step. Do it. In this case, the manufacturing process of the capacitor can be simplified. Therefore, a capacitor can be manufactured easily.

In another specific situation of the manufacturing method of the capacitor | condenser which concerns on this invention, an alloying process, an electrically conductive paste coating process, and a baking process are performed in this order.

In the present invention, a portion of the ground terminal connected to the second internal electrode is formed by the plating film. Unlike the fired film formed by immersing the conductive paste in accordance with the exposed portion of the internal electrode, the plated film is formed by plating growth from the exposed portion of the internal electrode, so that the plated film can be formed with high positional accuracy. Therefore, it is not necessary to consider the dispersion | variation at the time of apply | coating a conductive paste, and it is not necessary to make the part exposed from the capacitor | condenser main body of an internal electrode small in consideration of a variation. That is, the part exposed from the capacitor | condenser main body of an internal electrode can be enlarged. Therefore, the electrode cross-sectional area of the connection portion with the ground terminal of the second internal electrode can be made large, and the ESL can be made small. As a result, good insertion loss characteristics can be realized.

1 is a schematic perspective view of a capacitor according to an embodiment of the present invention.
2 is a schematic plan view of a capacitor according to an embodiment of the present invention.
3 is a schematic side view of a capacitor according to an embodiment of the present invention.
4 is a schematic cross-sectional view taken along the line IV-IV in FIG. 1.
FIG. 5 is a schematic cross-sectional view at the line VV in FIG. 1. FIG.
6 is a schematic cross-sectional view taken along the line VI-VI in FIG. 4.
FIG. 7 is a schematic cross-sectional view at line VII-VII in FIG. 5.
8 is a schematic cross-sectional view taken along the line VIII-VIII in FIG. 5.
9 is a schematic cross-sectional view of a capacitor according to a reference example.
10 is a graph showing insertion loss of a capacitor.
11 is a schematic cross-sectional view of a capacitor according to a first modification.
12 is a schematic cross-sectional view of a capacitor according to a second modification.
13 is a schematic cross-sectional view of a capacitor according to a third modification.

Hereinafter, an example of the preferable form which implemented this invention is demonstrated. However, the following embodiment is merely an illustration. This invention is not limited to the following embodiment.

1 is a schematic perspective view of a condenser of this embodiment. 2 is a schematic plan view of the capacitor of the present embodiment. 3 is a schematic side view of the capacitor of the present embodiment.

The capacitor | condenser 1 of this embodiment shown to FIGS. 1-3 is a capacitor used as a noise filter. As shown in FIGS. 1-3, the capacitor | condenser 1 contains the capacitor | condenser main body (ceramic body) 10. As shown in FIG. The capacitor body 10 is made of a dielectric. Specifically, the capacitor body 10 is made of, for example, a dielectric ceramic. Examples of the dielectric ceramic spheres, for example, and the like _{BaTiO 3, CaTiO 3, SrTiO 3} , CaZr0 3. Further, for example, subcomponents such as Mn compounds, Fe compounds, Cr compounds, Co compounds, and Ni compounds may be appropriately added to the capacitor body 10.

In this embodiment, the capacitor | condenser main body 10 is formed in substantially rectangular parallelepiped form. The capacitor body 10 includes first and second main surfaces 10a and 10b, first and second side surfaces 10c and 10d, and first and second end surfaces 10e and 10f. . Each of the first and second main surfaces 10a and 10b extends along the longitudinal direction L and the width direction W. As shown in FIG. Each of the first and second side surfaces 10c and 10d extends along the longitudinal direction L and the height direction H. As shown in FIG. Each of the first and second end faces 10e and 10f extends along the width direction W and the height direction H. As shown in FIG.

A plurality of first internal electrodes 11 and a plurality of second internal electrodes 12 are formed inside the capacitor body 10. The plurality of first and second internal electrodes 11 and 12 are alternately arranged to face the height direction H through the dielectric layer.

As shown in FIGS. 5 and 8, the first internal electrode 11 is formed to extend along the longitudinal direction L and the width direction W. As shown in FIG. The first internal electrode 11 is formed in a substantially rectangular shape. The first internal electrode 11 is exposed to the first and second end surfaces 10e and 10f. The first internal electrode 11 is not exposed to the first and second side surfaces 10c and 10d.

As shown in FIG. 4 and FIG. 7, the second internal electrode 12 is formed to extend along the longitudinal direction L and the width direction W. As shown in FIG. As shown in FIG. 4 and FIG. 7, the second internal electrode 12 includes an opposing portion 12a and an opposing portion 12a corresponding to the first internal electrode 11 in the height direction H. As shown in FIG. ) And first and second connecting portions 12b and 12c connected to each other.

As seen from the height direction H, the opposing part 12a is formed in the center part of the condenser main body 10. As shown in FIG. The opposing portion 12a is not exposed to the first and second side surfaces 10c and 10d and the first and second end surfaces 10e and 10f.

One end of the first connecting portion 12b is connected to the opposing portion 12a, and the other end thereof is exposed to the first side surface 10c. One end of the second connecting portion 12c is connected to the opposing portion 12a, and the other end thereof is exposed to the second side surface 10d. The length along each longitudinal direction L of the 1st and 2nd connection parts 12b and 12c is shorter than the length along the longitudinal direction L of the opposing part 12a.

The material for forming the first and second internal electrodes 11 and 12 is not particularly limited, but the first and second internal electrodes 11 and 12 preferably include Ni, for example. It is preferable that it consists of Ni.

1 to 3 and 6 to 8, the first signal terminal 15 is formed on the first end face 10e of the capacitor body 10. The first signal terminal 15 is formed to reach the first and second main surfaces 10a and 10b and the first and second side surfaces 10c and 10d while covering the first end face 10e. have. As shown in FIG. 8, the first signal terminal 15 is connected to the first internal electrode 11.

1 to 3 and 6 to 8, a second signal terminal 16 is formed on the second end face 10f of the capacitor body 10. The second signal terminal 16 is formed to reach the first and second main surfaces 10a and 10b and the first and second side surfaces 10c and 10d while covering the second end face 10f. have. As shown in FIG. 8, the second signal terminal 16 is connected to the first internal electrode 11.

In addition, the polarity of the potential to which the first and second signal terminals 15 and 16 are connected is not particularly limited. In this embodiment, an example in which the first and second signal terminals 15 and 16 are connected to the potential potential will be described.

6-8, in this embodiment, each of the 1st and 2nd signal terminals 15 and 16 is comprised by the laminated body of three conductive layers. Specifically, the first and second signal terminals 15 and 16 are the plastic conductive films 15a and 16a, the first plating films 15b and 16b, and the second plating films 15c and 16c. It is formed by the laminated multilayer film.

The baked conductive films 15a and 16a are films obtained by baking a conductive paste containing a glass component together with a conductive agent. For this reason, it is effectively suppressed that moisture enters into the capacitor | condenser main body 10 from the part in which the 1st and 2nd signal terminals 15 and 16 of the capacitor | condenser main body 10 are formed. Therefore, the fall of the reliability of the capacitor | condenser 1 resulting from ionization of the metal contained in the 1st and 2nd signal terminals 15 and 16 can be suppressed effectively.

The thickness of the plastic conductive films 15a and 16a is not specifically limited, For example, it can be set to about 10 micrometers-60 micrometers.

* It is preferable that the electrically conductive agent contained in the baking conductive films 15a and 16a is Cu, for example. This is because the adhesion to the internal electrodes 11 and 12 containing Ni is improved. In addition, when the first internal electrode 11 contains Ni and the baked conductive films 15a and 16a are formed into a baked conductive film containing Cu, the baked conductive film is baked at the time of baking the baked conductive films 15a and 16a. At the interface between the films 15a and 16a and the first internal electrode 11, Cu and Ni are alloyed to firmly connect the plastic conductive films 15a and 16a and the first internal electrode 11 to each other. Can be.

The first plating films 15b and 16b are formed on the plastic conductive films 15a and 16a. Although the formation material of 1st plating film 15b, 16b is not specifically limited, The 1st plating film 15b, 16b can be comprised by Ni plating, for example. By doing so, the solderability to solder is improved.

The second plating films 15c and 16c are formed on the first plating films 15b and 16b. Although the formation material of the 2nd plating film 15c, 16c is not specifically limited, The 2nd plating film 15c, 16c can be comprised by Sn plating, for example. By doing so, the solderability to solder is improved.

The thickness of the 1st and 2nd plating film 15b, 16b, 15c, 16c is not specifically limited, For example, it can be about 1 micrometer-about 5 micrometers, respectively.

1 to 3 and 6 to 8, the first and second ground terminals 17 and 18 are connected to the second internal electrode 12 on the outer surface of the capacitor body 10. Is formed. These first and second ground terminals 17 and 18 are terminals connected to the ground potential.

As shown in FIG. 1, FIG. 2, and FIG. 4, the 1st ground terminal 17 is formed in the center part of the 1st side surface 10c in the longitudinal direction L. As shown in FIG. The upper end of the first ground terminal 17 reaches the first main surface 10a. The lower end part of the 1st ground terminal 17 has reached the 2nd main surface 10b. That is, the 1st ground terminal 17 is located in the 1st part 17d located in the center part of the 1st side surface 10c in the longitudinal direction L, and is located on the 1st main surface 10a. The 2nd part 17e and the 3rd part 17f located on the 2nd main surface 10b are included. As shown in FIG. 4 and FIG. 7, the first portion 17d is connected to the first connecting portion 12b of the second internal electrode 12.

As shown in FIG. 1, FIG. 2, and FIG. 4, the 2nd ground terminal 18 is formed in the center part of the 2nd side surface 10d in the longitudinal direction L. As shown in FIG. The upper end of the second ground terminal 18 reaches the first main surface 10a. The lower end part of the 2nd ground terminal 18 has reached the 2nd main surface 10b. That is, the 2nd ground terminal 18 is located on the 1st part 18d located in the center part of the 2nd side surface 10d in the longitudinal direction L, and on the 1st main surface 10a. 2nd part 18e and 3rd part 18f located on the 2nd main surface 10b are included. As shown in FIG. 4 and FIG. 7, the first portion 18d is connected to the second connection portion 12c of the second internal electrode 12.

In addition, in this embodiment, in order to form each of the 1st and 2nd ground terminals 17 and 18 to reach the 1st and 2nd main surfaces 10a and 10b, the seed layer for energization in a plating process Need to be formed before the formation of the first and second ground terminals 17 and 18. However, the present invention is not limited to this. The first and second ground terminals 17 and 18 may be formed without forming the seed layer in advance. In that case, as shown in FIG. 13, each of the 1st and 2nd ground terminals 17 and 18 is formed only on the 1st or 2nd side surface 10c, 10d, and the 1st and 2nd It is not formed on the main surfaces 10a and 10b. That is, the first and second ground terminals 17 and 18 are constituted only by the first portions 17d and 18d.

As shown in FIG. 4, in the height direction H, the first and second connection portions 12b and 12c of the second internal electrode 12 and the first and second ground terminals 17 and 18. The ground dummy electrode 13 is formed between each of the second and third portions 17e, 18e, 17f, and 18f. As shown in FIG.4 and FIG.6, this ground dummy electrode 13 is connected to the 1st part 17d, 18d of the 1st or 2nd ground terminal 17,18. Thus, by providing the ground dummy electrode 13, all the wetted parts of the solder when soldering to the substrate can be formed at once by plating.

In this embodiment, as shown to FIG. 4, FIG. 6-FIG. 8, each of the 1st and 2nd ground terminals 17 and 18 is a 1st-3rd plating film 17a, 18a, 17b, It is comprised by the multilayer structure of 18b, 17c, 18c). The first plating films 17a and 18a are formed on the capacitor body 10. Specifically, the first plating film 17a is formed on the first side surface 10c. The first plating film 17a is connected to the first connecting portion 12b of the second internal electrode 12. The first plating film 18a is formed on the second side surface 10d. The first plating film 18a is connected to the second connecting portion 12c of the second internal electrode 12. The second plating films 17b and 18b are formed on the first plating films 17a and 18a. The third plating films 17c and 18c are formed on the second plating films 17b and 18b.

Each of the first to third plating films 17a, 18a, 17b, 18b, 17c, and 18c is not particularly limited as long as it is a plating film, but is preferably a wet plating film formed by wet plating, for example. In this case, it is not necessary to use a chemical solvent and the damage to the capacitor main body 10 can be reduced. In addition, since the process of applying a solvent to a specific point is not necessary, manufacturing cost can be reduced.

The material for forming the first to third plating films 17a, 18a, 17b, 18b, 17c, and 18c is not particularly limited. For example, it is preferable that the 1st plating films 17a and 18a are Cu plating films containing Cu. When the first plating films 17a and 18a are made of Cu plating films and the second internal electrodes 12 contain Ni, the first plating films 17a and 18a are subjected to heat treatment. Cu and Ni alloy at the interface between the second internal electrode 12 and the second internal electrode 12. For this reason, the 1st plating films 17a and 18a and the 2nd internal electrode 12 can be firmly connected.

It is preferable that the 2nd plating films 17b and 18b are Ni plating films containing Ni. In this case, solderability with respect to solder improves. It is preferable that the 3rd plating films 17c and 18c are Sn plating films containing Sn. In this case, solderability with respect to solder improves.

In addition, the thickness of the 1st-3rd plating film 17a, 18a, 17b, 18b, 17c, 18c is not specifically limited. The thickness of the 1st plating films 17a and 18a can be about 2 micrometers-about 10 micrometers, for example. The thickness of the second plating films 17b and 18b can be, for example, about 1 µm to 5 µm. The thickness of the third plating films 17c and 18c can be, for example, about 1 µm to 5 µm.

By the way, for example, as shown in FIG. 9, when the ground terminals 117 and 118 are formed of the fired film, the lengths L of the connecting portions 112b and 112c of the second internal electrode 112 are formed. It is necessary to make the length shorter than the length along the longitudinal direction L of the ground terminals 117 and 118. Although it is necessary to reliably cover the connecting portions 112b and 112c with the ground terminals 117 and 118, it is difficult to apply the conductive paste accurately with high positional accuracy. In addition, it is difficult to form a fired film thinly. For this reason, the ground terminals 117 and 118 become thicker, and the capacitor main body 110 needs to be made smaller. Therefore, the connection parts 112b and 112c also need to be made small with it. As a result, there arises a problem that the ESL is large and the noise is large.

In contrast, in the present embodiment, the first plating films 17a and 18a are formed on the first and second connection portions 12b and 12c. If it is a plating film, it can form with high positional precision. For this reason, it is not necessary to make the 1st and 2nd connection parts 12b and 12c small with respect to the 1st plating films 17a and 18a. That is, the electrode cross-sectional area of the 1st and 2nd connection part 12b, 12c can be enlarged. Therefore, for example, as shown in FIG. 10, ESL can be made small and noise can be made small. In addition, the data shown by the solid line in FIG. 10 are 1.0 mm in length, 0.5 mm in width, 0.3 mm in length of the ground terminal, and 0.3 mm in length along the length direction L of the connection portion of the second internal electrode. Phosphorus 3-terminal capacitors, which are data when the innermost layer of the ground terminal is formed of a plated film. The data shown by the dashed-dotted line in FIG. 10 has a length dimension of 1.0 mm, a width dimension of 0.5 mm, a length dimension of the ground terminal at 0.3 mm, and a dimension along the length direction L of the connection portion of the second internal electrode. It is data when the innermost layer of a ground terminal is comprised by the plastic film as a 3-terminal capacitor | condenser of mm. According to the data shown in FIG. 10, it is understood that the insertion loss characteristic can be improved by 10 dB or more by changing the innermost layer of the ground terminal from the plastic film to the plated film.

By the way, for example, in the case where the ground terminals 117 and 118 are plastic coatings containing a glass component, as shown in the example shown in FIG. 9, the capacitor body is formed from a portion where the ground terminals 117 and 118 of the capacitor body 110 are formed. The entry of moisture into the 110 can be effectively suppressed.

On the other hand, when the plating films 15a and 16a are formed on the surface of the capacitor main body 110 as in the present embodiment, the capacitor main body 110 is formed from the portion where the plating films 15a and 16a are formed. Moisture is easy to enter inside. However, in this embodiment, the first and second signal terminals 15 and 16 are connected to a constant voltage. For this reason, the ground terminals 17 and 18 are on the ground potential side. For this reason, even if moisture exists, the metal component contained in the ground terminals 17 and 18 will not be ionized. Therefore, the fall of the reliability of the capacitor | condenser 1 resulting from ionization of the metal contained in the ground terminals 17 and 18 can be suppressed effectively.

Next, an example of the manufacturing method of the capacitor | condenser 1 is demonstrated.

First, for example, a first internal electrode conductive paste such as a Ni paste is printed on a dielectric sheet to obtain a first sheet on which a conductive film for forming a first internal electrode is formed. Next, for example, a second conductive paste for forming internal electrodes, such as a Ni paste, is printed on the dielectric sheet to obtain a second sheet on which a conductive film for forming the second internal electrode is formed. Moreover, the 3rd sheet in which the electrically conductive film for ground dummy electrode formation was formed is obtained in the same order. And a laminated body is formed by laminating | stacking the 1st-3rd sheet | seat and the dielectric sheet on which the electrically conductive paste is not printed. Next, the laminate is fired (firing step). Thereby, the condenser main body 10 is produced. Thereafter, a conductive paste for forming the baked conductive films 15a and 16a of the first and second signal terminals 15 and 16 is applied onto the end faces 10e and 10f of the capacitor body 10 as the fired body. And the conductive paste films 15a and 16a are formed by baking (conductive paste coating step) (baking step). Moreover, the co-fire which performs a baking process and a baking process simultaneously may be sufficient.

Next, the plastic conductive films 15a and 16a of the capacitor body 10 are covered with a mask, and the first plating films 17a and 18a are formed to remove the mask, and then the first plating films 15b and 16b are removed. ), The second plated films 15c and 16c, and the second and third plated films 17b, 17c, 18b, and 18c are formed in this order to complete the capacitor 1 (plating film forming step). Let's do it. In addition, the capacitor body 10 is heated after the plating film is formed (alloying step). In this alloying step, after the first plating films 17a and 18a are formed and the capacitor body 10 is heated, the interface between the first plating films 17a and 18a and the second internal electrode can be alloyed. There is an increase in bonding strength. In addition, when the condenser main body 10 is heated after the formation of the first plating films 15b and 16b to serve as a baking step and an alloying step, the plastic conductive films 15a and 16a and the first plating film 15b are used. And 16b can be alloyed, and at the same time, the first plating films 17a and 18a and the second internal electrode can be alloyed. Therefore, the bonding strength between the first plating films 17a and 18a and the second internal electrodes and the bonding strength between the plastic conductive films 15a and 16a and the first plating films 15b and 16b are increased. . Thus, the baking process and the alloying process are performed simultaneously, and the manufacturing process of the capacitor | condenser 1 can be simplified.

In the above example, an example in which the baking step, the plating film forming step, and the alloying step are performed in this order has been described. However, this invention is not limited to this structure. Prior to the baking step, a plating film forming step may be performed and the baking step and the alloying step may be performed simultaneously. Specifically, the first and second signal terminals 15 and 16 and the first and second ground terminals 17 and 18 may be formed in the following manner.

First, plating is performed without forming the plastic conductive films 15a and 16a on the surface of the capacitor body 10. As a result, as shown in FIG. 11, the first plating films 17a and 18a are formed on the side surfaces 10c and 10d, and the first and second signal terminals 15 are formed on the end surfaces 10e and 10f. And third plating films 15d and 16d for forming 16 are formed.

Next, the electrically conductive paste is apply | coated and baked on 3rd plating film 15d, 16d, and the baked conductive film 15a, 16a containing a glass component is formed. In this case, the alloying process of the 3rd plating films 15d and 16d and the 1st plating films 17a and 18a is also performed by the heating in this baking process. That is, a baking process and an alloying process are performed simultaneously. Moreover, after performing the alloying process by the heating of the 1st plating film 17a, 18a and the 3rd plating film 15d, 16d, you may form the baking conductive film 15a, 16a.

Thereafter, similarly to the above embodiment, the first plating films 15b and 16b, the second plating films 15c and 16c, and the second and third plating films 17b, 17c, 18b and 18c. Are formed in order, and the capacitor | condenser 1 is completed (plated film formation process).

As in this modification, the baking step and the alloying step are performed at the same time, thereby simplifying the manufacturing step of the capacitor 1. Therefore, the capacitor | condenser 1 can be manufactured easily.

Thus, in the baking process performed to bake the baked conductive films 15a and 16a, gas is generated from the organic solvent or the like contained in the conductive paste. For example, when baking and alloying are performed at the same time after forming a conductive paste layer and forming a plating film thereon, there is a possibility that the gas generated from the conductive paste layer is blocked by the plating film and cannot escape from the conductive paste layer. If the gas does not sufficiently escape from the conductive paste layer, bubbles remain in the plastic conductive film. If bubbles exist in the plastic conductive film, bubbles may explode at the time of mounting the capacitor, and there is a fear that the solder may scatter. On the other hand, when the baking conductive films 15a and 16a are formed after the plating film is formed, the gas is likely to come off in the baking step, and bubbles are hard to remain. Therefore, the scattering of the solder at the time of mounting can be suppressed.

In addition, as in the above embodiment and the present modification, the first and second signal terminals 15 and 16 have a multilayer structure having a different structure of the plating film and the plastic conductive film, for example, when only the plating film is configured. Alternatively, when mounted on a substrate, the effect of suppressing a decrease in reliability due to the intrusion of moisture contained in the atmosphere around the chip is also obtained. In addition, the main cause of the decrease in reliability when moisture intrudes is considered to be that the metal component in the plating film is ionized by the moisture that has invaded the signal terminal connected to the electrostatic potential.

In addition, in the said embodiment or this modification, the 1st and 2nd ground terminals 17 and 18 are comprised by the multilayer structure of the other structure of the plating films 17a-17c, 18a-18c. That is, the first and second ground terminals 17 and 18 are constituted only by the plated film, and do not include the plastic conductive film.

For example, it is also conceivable to include a plastic conductive film in the ground terminal. However, when the plastic conductive film is included in the ground terminal, it is necessary to apply the conductive paste accurately on a part of the side surface, but it is difficult to apply the conductive paste on the part of the side surface with high positioning accuracy because it involves mechanical positioning. For this reason, the positioning accuracy of a ground terminal will fall.

In contrast, in the case where the first and second ground terminals 17 and 18 are constituted only by the plating film as in the above-described embodiment or the present modification, the mechanical positioning is not necessary because the plating is performed. The ground terminals 17 and 18 of 2 can be formed with high positional accuracy.

12 is a schematic cross-sectional view of a capacitor according to a second modification. As shown in FIG. 12, you may further provide 4th plating film 15e and 16e between the baking conductive films 15a and 16a and the 1st plating films 15b and 16b. In this case, the fourth plating films 15e and 16e and the first plating films 17a and 18a include the same Cu, the first plating films 15b and 16b, and the second plating films ( It is preferable that 17b and 18b contain the same Ni, and the 2nd plating films 15c and 16c and the 3rd plating films 17c and 18c contain Sn same. By doing so, after apply | coating electroconductive paste to 10e and 10f at the cross section of the capacitor | condenser main body 10, Cu plating process is performed to the whole capacitor | condenser main body 10, and the 4th plating film 15e and 16e and 1st Plating films 17a and 18a can be formed by a plating process containing the same Cu. In addition, after simultaneously forming the first plating film and the fourth plating film, both the baking process and the alloying process may be performed, and the capacitor body 10 may be thermally treated, and conductive paste may be applied to the end surface of the capacitor body 10 at 10e and 10f. A baking process may be performed after application | coating, and after that, a 1st plating film and a 4th plating film may be formed simultaneously, and an alloying process may be performed. In addition, when performing a baking process before an alloying process, the cofferfire which performs the baking process and baking process of the capacitor | condenser main body 10 simultaneously may be sufficient. After the fourth plating films 15e and 16e and the first plating films 17a and 18a are formed, the first plating films 15b and 16b and the second plating films 17b and 18b are the same. Simultaneously formed by a plating process containing Ni, second plating films 15c and 16c and third plating films 17c and 18c are then formed by a plating process containing the same Sn. In addition, when the 1st plating films 15b and 16b and the 2nd plating films 17b and 18b contain Ni, you may perform a baking process and an alloying process after this plating film formation process.

1: condenser 10: condenser body
10a: first main surface of the condenser body 10b: second main surface of the condenser body
10c: first side face of the condenser body 10d: second side face of the condenser body
10e: first cross section of condenser body 10f: second cross section of condenser body
11: first internal electrode 12: second internal electrode
12a: opposing portion of the second internal electrode 12b: first connecting portion
12c: second connection portion 13: ground dummy electrode
15: first signal terminal 15a, 16a: plastic conductive film
15b, 16b: first plating film 15c, 16c: second plating film
15d, 16d: third plating film 15e, 16e: fourth plating film
16: second signal terminal 17: first ground terminal
17a, 18a: first plating film 17b, 18b: second plating film
17c, 18c: third plating film 17d, 18d: first portion
17e, 18e: second part 17f, 18f: third part
18: second ground terminal

Claims (1)

A first and second main surfaces made of a dielectric material and extending in the longitudinal direction and the width direction, first and second side surfaces extending in the longitudinal direction and the height direction, and the width direction and the height direction. A rectangular parallelepiped condenser body having first and second cross sections extending along;
A first internal electrode formed inside the capacitor body;
A second internal electrode formed inside the condenser main body and facing the first internal electrode;
A first signal terminal formed at said first end face and connected to said first internal electrode;
A second signal terminal formed at said second end face and connected to said first internal electrode;
A capacitor formed on a portion of the first side surface to be connected to the second internal electrode and including a ground terminal connected to a ground potential,
The ground terminal has one or a plurality of plating films formed on the condenser main body and directly connected to the second internal electrodes;
And the signal terminal comprises a plastic conductive film.

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