JPH11251182A - Manufacture of ceramic electronic component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the transfer property and to ensure enough electrical properties, when a conductive layer is formed on a ceramic sheet through transfer in a method for manufacturing a ceramic electronic component. SOLUTION: A method for manufacturing a ceramic electronic component has a step for preparing a ceramic sheet comprised of a ceramic component and at least one type of organic substance, a step for forming a conductive layer 14 comprised of a metal component and at least one type of organic substance on a base film 12 via a releasing layer 13, a step for transferring the conductive layer 14 on the ceramic sheet, a step for obtaining a laminate by transferring alternately a ceramic sheet and a conductive layer 14 several times and a step for firing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a ceramic electronic component such as a multilayer ceramic capacitor.

[0002]

2. Description of the Related Art FIG. 4 is a cutaway perspective view showing a part of a general multilayer ceramic capacitor as an example of a ceramic electronic component as a background of the technology relating to the present invention. In FIG. 4, 1 is a ceramic dielectric layer, 2 is an internal electrode, 3 is an external electrode, and the internal electrode 2 is connected to each external electrode 3.

Hereinafter, a method for manufacturing a conventional multilayer ceramic capacitor will be described. First, the ceramic dielectric layer 1
The ceramic sheet becomes a dielectric material such as barium titanate and a binder component such as polyvinyl butyral,
A plasticizer component such as benzyl butyl phthalate and a solvent component are mixed and slurried, and then formed on a support such as PET using a doctor blade method. Usually, the thickness of the dried ceramic sheet is about 5 to 50 μm.

[0004] Next, a plurality of conductor layers are formed on a support such as a polyethylene terephthalate film (hereinafter referred to as a PET film) by a printing method using a conductor paste serving as an internal electrode 2 such as palladium or nickel, and dried. .
When the thickness of the conductor layer is small, the conductor layer becomes discontinuous due to sintering shrinkage during firing and may cause a decrease in capacitance. Then PET
Conductive layers and ceramic sheets formed on the film are alternately stacked by thermal transfer to obtain a laminate. The laminate was cut into a desired size, fired, and provided with external electrodes 3 on both end faces (for example, see Japanese Patent Publication No. 25381/1993).

[0005]

However, when the conductive layer formed on the support is thermally transferred onto the ceramic sheet, the conductive layer may not be completely transferred and transferred from the support onto the ceramic sheet. is there. In this case, after firing, the internal electrodes 2 are in a discontinuous state, resulting in a failure of quality as a multilayer ceramic capacitor such that sufficient capacitance cannot be obtained or variation occurs.

Accordingly, an object of the present invention is to provide a ceramic electronic component having stable electrical characteristics by completely transferring and transferring a conductive layer from a support onto a ceramic sheet.

[0007]

To achieve this object, a method for manufacturing a ceramic electronic component according to the present invention comprises the steps of: preparing a ceramic sheet comprising a ceramic component and at least one or more organic substances; Forming a conductive layer made of a metal component and at least one or more organic substances via a release layer, transferring the conductive layer onto the ceramic sheet, and further forming the ceramic sheet and the Transferring the conductor layers alternately a plurality of times to obtain a laminate, and baking the laminate, characterized in that the conductor layer on the support via a release layer Because it is formed, the releasability from the support is improved than before, and the conductor layer is completely transferred from the support to the ceramic sheet,
The transition can be made, and the above object can be achieved.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION
Preparing a ceramic sheet comprising a ceramic component and at least one or more organic materials; forming a conductive layer comprising a metal component and at least one or more organic materials on a support via a release layer; Transferring a conductive layer onto the ceramic sheet, further transferring the ceramic sheet and the conductive layer alternately a plurality of times thereon to obtain a laminate, and firing the laminate. A method for manufacturing a ceramic electronic component, wherein a conductive layer is formed on a support via a release layer, so that the releasability from the support is improved as compared with the conventional method, and The conductor layer can be completely transferred and transferred from the body to the ceramic sheet, and a ceramic electronic component having stable electrical characteristics can be obtained.

According to a second aspect of the present invention, the softening point of the release layer is higher than the softening point of the organic substance contained in the conductor layer. When the conductive layer is thermally transferred onto the ceramic sheet, deformation of the conductive layer can be suppressed, and the transfer can be performed with high accuracy.

[0010] The invention according to claim 3 is an acrylic resin,
2. The method for manufacturing a ceramic electronic component according to claim 1, wherein the release layer is formed of at least one of an epoxy resin and a melamine resin, and the conductor layer is formed on the release layer with high accuracy. The transferability of the conductor layer to the ceramic sheet can be improved.

According to a fourth aspect of the invention, there is provided a method of manufacturing a ceramic electronic component according to any one of the first to third aspects, wherein the size of the release layer is made larger than that of the ceramic sheet. When transferring a conductor layer onto a ceramic sheet, it is possible to prevent adhesion between the ceramic sheet and the support and to suppress peeling between the ceramic sheets.

According to a fifth aspect of the present invention, at least one kind of the organic substance contained in the conductor layer and the organic substance contained in the ceramic sheet are the same. The method for manufacturing a ceramic electronic component according to any one of the above, wherein the adhesiveness between the conductor layer and the ceramic sheet is improved, and the transfer of the conductor layer to the ceramic sheet is facilitated.

An embodiment of the present invention will be described below with reference to the drawings, taking a multilayer ceramic capacitor as an example.

(Embodiment 1) FIG. 1 shows a conductive layer 14 formed on a base film 12 as a support such as a PET film via a release layer 13 in the present embodiment.
FIG.

FIG. 2 is a sectional view showing the ceramic sheet 11 formed on the base film 12.

FIG. 3 is a process diagram showing a lamination process. After transferring the plurality of ceramic sheets 11 onto the support 15, the conductor layer 14 formed on the base film 12 via the release layer 13 is transferred onto the ceramic sheet 11.

FIG. 4 is a cutaway perspective view of a multilayer ceramic capacitor shown as an example of a ceramic electronic component.
1 is a ceramic dielectric layer, 2 is an internal electrode, 3 is an external electrode, and the internal electrode 2 is connected to each external electrode 3.

Next, a method of manufacturing a multilayer ceramic capacitor using nickel as the internal electrode 2 will be described.

First, a dielectric material such as barium titanate;
After mixing a polyvinyl butyral-based binder component, dibutyl phthalate as a plasticizer component, and butyl acetate as a solvent component to form a slurry, a ceramic sheet 11 is formed on the base film 12 shown in FIG. 2 using a doctor blade method. . On the other hand, as shown in FIG.
Is prepared, and a nickel paste is formed on the release layer 13 as a conductor layer 14 to be the internal electrode 2 in a predetermined pattern by screen printing or gravure printing, or the like. dry. The nickel paste contains an organic binder component in addition to the nickel powder and the solvent. It is common to use aliphatic naphtha, aromatic naphtha, terpineol as a solvent, and ethyl cellulose as an organic binder component. Most of the organic solvent is scattered in the dried nickel paste, leaving only the metal component and the organic binder component. Next, the laminating step will be described with reference to FIG. First, after laminating a plurality of ceramic sheets 11 on the support 15, the conductor layer 14 is transferred onto the ceramic sheet 11 by pressing and heating from the side where the conductor layer is formed. Next, the ceramic sheet 11 and the conductor layer 14 are alternately transferred a desired number of times, and a plurality of ceramic sheets 11 are stacked thereon to obtain a laminate before cutting. The transfer of the conductor layer 14 means that the organic components in the conductor layer 14 and the ceramic sheet are slightly softened by heating, the contact area between the two is increased by pressing, and the adhesion between the two is induced. 13 to promote separation. When a general ethylcellulose-based organic binder is used as an organic binder contained in the nickel paste, the organic binder may be 60 ° C to 140 ° C.
° C., it is possible to perform efficient transcription under conditions of ^{50kg / cm 2 ~150kg / cm 2} . When the temperature is lower than 60 ° C., sufficient softening of the organic component cannot be expected.
The base film 12 such as a film is deteriorated.
Furthermore, mixing the same organic component as that contained in the ceramic sheet 11 into the conductor layer 14 can increase the adhesive force between the conductor layer 14 and the ceramic sheet 11, so that the conductor layer 14 Can be easily transferred. As described above, the present invention is carried out by using a metal paste such as a nickel paste, and the metal paste exhibits an effect only when it is composed of a metal component and an organic component. However, when manufacturing a high-lamination product, heat during transfer accumulates inside the laminate, and the ceramic sheet 11 is stretched to induce softening of the organic component. is there.
Therefore, it is preferable that the temperature of the laminate at the time of transfer be lower than the softening point of the organic component in the laminate. Also,
When the release layer 13 is smaller than the base film 12 and smaller than the ceramic sheet 11, the base film 12 and the ceramic sheet 11 come into direct contact with each other when the conductor layer 14 is transferred, and the ceramic sheet 11 is peeled off. There are cases. As a result, the sintered body has structural defects,
It is important to make the size of the release layer 13 larger than that of the ceramic sheet 11 because a good product cannot be obtained.

Thereafter, the laminate is cut into chips, degreased in air at 350 ° C., and fired at 1300 ° C. in a reducing atmosphere composed of nitrogen and hydrogen. By this firing, a sintered body is obtained in which the ceramic dielectric layer 1 mainly containing barium titanate and the internal electrode 2 mainly containing nickel are sintered simultaneously. The size of the sintered body after firing was about 3.
The thickness of the ceramic dielectric layer 1 between the internal electrodes 2 is 5 μm, and the thickness of the internal electrodes 2 is 1.8 μm.
m. Next, copper external electrodes 3 are formed on the exposed end faces of the internal electrodes 2 of the sintered body, and the multilayer ceramic capacitor shown in FIG. 4 is obtained. As an embodiment of the present invention, a ceramic sheet 11 having a thickness of 9 μm and a thickness of 2.5 μm
Using 100 m of the conductive layers 14, transfer and lamination of 100 sheets were performed, and the transferability of the conductive layers 14 onto the ceramic sheet 11 and the capacitance of the laminated ceramic capacitor after firing were measured and evaluated. Was done. For comparison, a base film 12 having no release layer 13 was also prepared,
Similarly, the transferability and the capacitance are compared with the case where the release layer 13 is formed. Regarding the transferability, the ratio of the conductive layer 14 remaining on the base film 12 side after the transfer of the conductive layer 14 is shown as a ratio to the total pattern weight. The measurement results of the transferability and the capacitance are shown in (Table 1).

[0021]

[Table 1]

In the case where the release layer 13 is provided, it can be seen that the transfer is almost completely performed. On the other hand, when the release layer 13 was not provided, sufficient capacitance was not obtained because the transfer of the conductor layer 14 was insufficient. From this result, the release layer 13 was formed on the base film 12.
It can be said that the transferability can be sufficiently improved by forming the conductive layer 14 containing an organic component through the layer and transferring the layer onto the ceramic sheet 11. As a result, it is possible to suppress a fatal failure as a multilayer ceramic capacitor such as a variation or a decrease in capacitance due to a transfer failure of the conductor layer 14, which has a great effect on improving the yield.

Hereinafter, important points regarding the present invention will be described. (1) The release layer 13 prevents the occurrence of repelling during printing of the nickel paste, and the conductor layer 1 is formed on the release layer 13 with high accuracy.
In order to form No. 4, it is necessary that the solvent component in the nickel paste and the release layer 13 have good wettability. (2) It is desired that the release layer 13 does not cause a chemical reaction with the solvent component in the nickel paste in order to prevent the releasability of the conductor layer 14 during transfer from being significantly deteriorated. (3) Further, in order to improve lamination accuracy, the release layer 13 is required to have a performance of not being softened or deteriorated by pressure and heat during lamination. (4) Further, it is necessary to form the release layer 13 and the base layer 12 so that the bond strength between the release layer 13 and the conductor layer 14 can be smaller than the bond strength between the release layer 13 and the base film 12. (5) In the present embodiment, a release layer 13 having a thickness of 1 μm was formed on a base film 12 having a thickness of 75 μm, and a conductor layer 14 having a thickness of 5 μm was formed thereon. Release layer 13
Has little influence on the transferability of the conductor layer 14. What is important is that the conductive layer 14 and the base film 12 are always in a non-contact state, that is, the release layer 13 between the conductive layer 14 and the base film 12 has no defect or the like. The surface on which the conductor layer 14 is formed is to be as smooth and horizontal as possible. (6) It is effective to use an acrylic resin, an epoxy resin, a melamine resin or a mixed resin thereof as the release layer 13 in order to satisfy the performances of the above (1) to (5). When using an acrylic resin, it is preferable to use a mixture with an epoxy resin and a melamine resin in order to improve thermal stability. (7) As described in (4) above, in order to improve the bonding strength between the release layer 13 and the base film 12, unevenness is provided on the surface of the base film 12 where the release layer 13 is formed, and the release layer 13 is formed. It is preferable to increase the contact area with the metal. (8) In order to prevent the release layer 13 from softening, the temperature at the time of drying the conductive layer 14 and the temperature at the time of transfer need to be lower than the softening point of the release layer 13. (9) It is desirable that the temperature at the time of de-buying be such that the solvent can be removed from the laminate, and the oxidation of the metal component (nickel in the present embodiment) in the conductor layer 14 does not proceed too much. Specifically, it is desirable to carry out at 350 ° C. or lower. (10) Although nickel is used as the material of the conductor layer 14, a base metal such as copper or a noble metal such as palladium or silver-palladium may be used. (11) When sintering the laminate, a reducing atmosphere is used to prevent the metal component (nickel in the present embodiment) in the conductor layer 14 from being excessively oxidized and not functioning as the internal electrode 2. It is done in. (12) In the above embodiment, a multilayer ceramic capacitor has been described as an example. However, the present invention is a general ceramic electronic component having a step of laminating a ceramic sheet and a conductor layer formed using a metal paste, for example, a multilayer ceramic capacitor. Varistors, multilayer thermistors, multilayer filters, ferrite parts,
Similar effects can be obtained in the manufacture of a ceramic multilayer substrate.

[0024]

As described above, according to the present invention, by forming a conductor layer on a support via a release layer, the conductor layer is easily released from the support, and the conductor layer is deposited on the ceramic sheet. Transferability is improved.

As a result, it is possible to reduce defective characteristics due to poor transfer of the conductor layer to the ceramic sheet, and to manufacture ceramic electronic components having stable electric characteristics with a high yield.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a conductor layer formed on a release layer according to an embodiment of the present invention.

FIG. 2 is a sectional view of a ceramic sheet formed on a base film according to one embodiment of the present invention.

FIG. 3 is a cross-sectional view showing a transfer lamination process in one embodiment of the present invention.

FIG. 4 is a partially cutaway perspective view of a general multilayer ceramic capacitor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ceramic dielectric layer 2 Internal electrode 3 External electrode 11 Ceramic sheet 12 Base film 13 Release layer 14 Conductive layer 15 Support

Continuing from the front page (72) Inventor, Kato Omiya, Kazuma, Osaka 1006, Kazuma, Matsushita Electric Industrial Co., Ltd.

Claims (5)

[Claims] A step of preparing a ceramic sheet comprising a ceramic component and at least one or more kinds of organic substances;
A step of forming a conductor layer made of at least one kind of organic substance, a step of transferring the conductor layer onto the ceramic sheet, and a step of alternately transferring the ceramic sheet and the conductor layer a plurality of times thereon, and laminating the same. A method for manufacturing a ceramic electronic component, comprising: obtaining a body; and firing the laminate. 2. The method for manufacturing a ceramic electronic component according to claim 1, wherein the release layer has a softening point higher than a softening point of an organic substance contained in the conductor layer. 3. The method according to claim 1, wherein the release layer contains at least one of an acrylic resin, an epoxy resin, and a melamine resin. 4. The method according to claim 1, wherein the size of the release layer is larger than that of the ceramic sheet. 5. The organic substance contained in the conductor layer is at least one kind or more identical to the organic substance contained in the ceramic sheet. Of manufacturing ceramic electronic components.