JPH0465190A - Manufacture of laminated ceramic electronic part - Google Patents

Abstract

PURPOSE:To efficiency mass-produce laminated ceramic electronic parts in desired shapes by deforming them in reverse direction according to the quantity of the deformation arising in baking, at the stage of ceramic crude chips. CONSTITUTION:A ceramic crude chip 20 is obtained by laminating a plurality of ceramic green sheets 11-15 and pressing them in thickness direction. Thereupon, according to the forecast quantity of the deformation by baking, the ceramic crude chip 20 is deformed in the direction reverse to the deformation by baking, thus the ceramic crude chip 10A is prepared. Then by baking the ceramic crude chip 20A at a temperature of 1000 deg.C in neutral atmosphere, a multilayer ceramic board 21 can be obtained.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for manufacturing multilayer ceramic electronic components such as multilayer ceramic substrates and multilayer capacitors.
In particular, the present invention relates to a method for manufacturing a multilayer ceramic electronic component in which the steps from preparing a molded multilayer ceramic green chip to firing are improved.

[Conventional technology]

With the progress of surface mounting of electronic components, various laminated ceramic electronic components including multilayer ceramic substrates have been developed. Among these, a conventional method for manufacturing a multilayer ceramic electronic component will be explained by taking a multilayer ceramic substrate as an example.

When manufacturing a multilayer ceramic substrate, first, a plurality of ceramic green sheets are prepared.

A metal-containing conductive paste is printed on any one of the plurality of ceramic green sheets to form an electrode structure. A ceramic raw chip 1 shown in FIG. 2(a) is obtained by laminating a plurality of prepared ceramic green sheets and pressing them together in the thickness direction.

In the ceramic raw chip 1, a plurality of ceramic green sheets are stacked in the thickness direction, and an appropriate number of conductive pastes 2 (indicated by broken lines) are printed and arranged inside.

As the metal-containing S-electrode paste, a material prepared by kneading metal particles such as Ag, Ag+Pd, or Cu with a binder and an organic vehicle is used. Of these, Cu
is oxidized when exposed to a high-temperature atmosphere, so when a Cu-containing conductive paste is used, the firing process described below is performed in step 1.
It is carried out at temperatures below about 1,000°C, so
The green ceramic chip 1 is constructed using a low-temperature firing type ceramic material fired at a temperature of approximately 000°C or less.

Next, the ceramic green chip 1 obtained as described above
By firing, an integrally fired ceramic sintered body having an electrode structure formed therein can be obtained. Furthermore, a multilayer ceramic substrate can be obtained by providing an external electrode electrically connected to the internal electrode structure on the outer surface of the sintered body.

[Problems to be Solved by the Invention] Ceramics and the metal particles contained in the above-mentioned conductive paste have very different thermal shrinkage rates.

Therefore, when the electrode flIa made of conductive paste is unevenly distributed in the green ceramic chip l, for example, when the conductive paste 2 is unevenly distributed upward as shown in FIG. There was a problem in that the solid body was deformed as shown in FIG. 2(b) due to the difference in thermal contraction rate.

In other words, since metal has a higher thermal contraction rate than ceramics, the upper surface side of the sintered body 3 contracts more than the lower surface side due to the effect of thermal contraction of the conductive paste unevenly distributed in the upper part, and as a result, the As shown in Figure 2(b), the sintered body 3 has both end edges 3a and 3b bent upward.
The problem was that I could only get it.

Therefore, in the past, a flat weight was placed from above the obtained sintered body 3! ! ! A flat plate-shaped sintered body was obtained by placing the sintered body in that state and heating it to a temperature slightly lower than the firing temperature.

However, the method for correcting deformation as described above requires a series of complicated steps such as placing a flat weight and heating the product to a temperature slightly lower than the firing temperature. Also, it took a considerable amount of time.

The above-mentioned problem has been a problem not only in the production of multilayer ceramic substrates but also in the production of other laminated ceramic electronic components using raw ceramic chips formed by laminating a plurality of ceramic green sheets.

Therefore, an object of the present invention is to provide a method for manufacturing a laminated ceramic electronic component that can produce a laminated ceramic sintered body without deformation such as bending or warping through a relatively simple process.

[Means to solve the problem]

In the method for manufacturing a laminated ceramic electronic component of the present invention, first, a plurality of ceramic green sheets are laminated;
A green ceramic chip is prepared in which an electrode structure made of a metal-containing conductive paste is formed inside. Next, this ceramic raw chip is deformed by an amount equivalent to the amount of deformation during firing in the opposite direction to the deformation during firing. Thereafter, the deformed ceramic green chip is fired.

(Function) In the present invention, at the stage of the ceramic raw chip before firing, the ceramic raw chip is deformed in the opposite direction to the deformation during firing by an amount equivalent to the amount of deformation during firing. That is, in view of the fact that deformation due to the difference in thermal contraction rate between metal-containing conductive paste and ceramics is unavoidable, the present invention predicts the amount of deformation due to firing, and pre-fires the raw ceramic chip by the amount of deformation. Deform it in the opposite direction to the deformation caused by
The aim is to obtain a laminated ceramic sintered body with a desired shape by actively utilizing the deformation phenomenon during the firing process.

Since the deformation is performed at the stage of the ceramic raw chip, which is relatively easy to process, the deformation step before firing is performed easily and efficiently.

In addition, the deformation during firing is significant when the conductive paste is unevenly arranged within the ceramic raw tube.
In such a case, with the method of the present invention, it is possible to greatly and easily deform the raw ceramic chip at the stage where it is easy to process, so it is relatively easy to obtain a laminated ceramic sintered body in the desired shape. can.

[Explanation of Examples]

An embodiment of the present invention will be described with reference to FIGS. 1(a) to 1(d).

First, as shown in FIG. 1(a), BaO, Si0. ,
A plurality of ceramic green sheets 11 to 1 made of a low-temperature sinterable ceramic material containing B, O, and AN, O.
Prepare 5. Of these, ceramic green sheet 1
2.13, in order to form an electrode structure, a conductive paste containing Cu is printed to form electrode parts 16 to 19.

In this embodiment, a Cu-containing conductive paste is used, but other conductive pastes containing metal particles such as Ag or Ag+Pd may also be used.

However, in the case of Cu, the thermal shrinkage rate is very large, so the use of the method of this embodiment is particularly effective.

Note that the surface of Cu is oxidized at a temperature of about 1000°C, so in this example, the above-mentioned ceramic material that can be fired at a temperature of 1000°C or less is used.

Further, the electrode sections 16 to 19 are merely illustrated as examples and schematically, and in reality, they may be configured in an appropriate planar shape depending on the required electronic component function and wiring structure. It is something.

By stacking a plurality of ceramic green sheets 11 to 15 and pressing them together in the thickness direction, a raw ceramic chip 20 shown in FIG. 1(b) is obtained. If this raw ceramic chip 20 is fired in this state, it will be as shown in Fig. 2(b).
), only a greatly deformed sintered body is obtained.

Therefore, in this embodiment, the ceramic green chip 20 is deformed in the opposite direction to the deformation due to firing, depending on the amount of deformation expected due to firing. In this way, a deformed ceramic raw chip 20A shown in FIG. 1(C) is prepared.

Note that the above deformation amount can be easily predicted by firing the raw ceramic chip 20 shown in FIG. 1(b) as a trial.

In addition, in order to deform the ceramic raw chip 20 and process it into the ceramic raw chip 2OA,
This can be easily done by preparing a mold according to the external shape of A and hot pressing. That is, in this embodiment, since the deformation process is carried out at the stage of the comparatively soft raw ceramic chip 20, the above process can be carried out in an extremely short time and easily.

Thereafter, the raw ceramic chip 2OA was fired at a temperature of 1000°C in a neutral atmosphere to obtain the shape shown in Figure 1 (
A multilayer ceramic substrate 21 shown in d) can be obtained. That is, the raw ceramic chip 2OA is deformed by firing, and the multilayer ceramic substrate 21 in its original flat shape is transformed.
is obtained.

As described above, according to the manufacturing method of this embodiment, it is possible to easily obtain the ceramic multilayer substrate 21 without warping or bending. It is more preferably used when the That is, if the electrode portions made of conductive paste are unevenly distributed, the overall shape will change significantly due to firing.

It is very difficult to correct such a large amount of deformation by processing after obtaining the sintered body as in the conventional method, but in this example, the deformation is performed at the stage of the soft green chip before firing. It is possible to easily deal with the amount of deformation regardless of its size.

Further, although the above description relates to an embodiment applied to a method for manufacturing a multilayer ceramic substrate, the present invention also relates to a method for manufacturing other multilayer ceramic electronic components such as a multilayer capacitor, a multilayer inductor, or a multilayer piezoelectric component. Can be generally applied.

〔Effect of the invention〕

According to the present invention, at the stage of a raw ceramic chip, deformation processing is performed in the opposite direction depending on the amount of deformation that occurs during firing. Since it is a raw ceramic chip, this deformation process can be performed extremely easily and in a short time. Therefore, it becomes possible to efficiently mass-produce laminated ceramic electronic components having a desired shape.

[Brief explanation of drawings]

FIGS. 1(a) to 1(d) are diagrams for explaining a manufacturing method according to an embodiment of the present invention, and FIG. 1(a) shows a process of printing a prepared ceramic green sheet and conductive paste. FIG. 1(b) is an exploded perspective view showing the shape of the electrode part formed by the process, FIG. 1(b) is a perspective view showing the laminated green chip, FIG. FIG. 1(d) is a schematic perspective view of the multilayer ceramic substrate obtained by firing, and FIGS. 2(a) and (b)
) are perspective views showing a ceramic raw chip prepared by a conventional method and a sintered body obtained by firing the ceramic raw chip, respectively. In the figure, 11 to 15 are ceramic green sheets,
Reference numerals 16 to 19 indicate electrode portions formed by printing conductive paste, 20 indicates a ceramic ceramic chip, 2OA indicates a modified ceramic green chip, and 21 indicates a multilayer ceramic substrate. Figure 1

Claims (2)

[Claims] (1) Deformation when the ceramic green chip is prepared by laminating a plurality of ceramic green sheets and has an electrode structure made of a metal-containing conductive paste inside, and is fired. According to
deforming in the opposite direction to the deformation by an amount equivalent to the amount of deformation during firing, and firing the deformed ceramic green chip;
A method for manufacturing a laminated ceramic electronic component, characterized by comprising each step. (2) The method for manufacturing a laminated ceramic electronic component according to claim 1, wherein the green ceramic chip is one in which the conductive paste is disposed non-uniformly.