JPH1140457A - Manufacture of laminate ceramic electronic component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture a high-quality laminate ceramic electronic component having no structural defect by fixing approximately one surface of a laminate to a support board, sealing it and forming with a hydraulic pressure of over a specified value. SOLUTION: A laminate composed of a support board 4, film 5 and laminate 3 is covered with a packing film 6 and vacuum-sealed around the film 6 to obtain a vacuum package 7. Using an isotropic pressure forming process composed of a receiving die 8 contg. a pressure medium, i.e., water 10 and press die, the vacuum packages 7 inserted in the die 8 with the water 10 are pressed by the die 9 to isotropically press and form them 7 at a water pressure f1 applied in all directions and hydrostatic pressure of 1000 kgf/cm<2> or more. Thereafter the laminates 3 are taken out from the packages 7 and cut and backed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for manufacturing a multilayer ceramic electronic component. More particularly, the present invention relates to an improved method for manufacturing a multilayer ceramic electronic component using isostatic pressing means by hydrostatic pressure.

[0002]

2. Description of the Related Art In manufacturing electronic components such as a multilayer capacitor, a multilayer inductor, a multilayer alumina substrate, a multilayer varistor, and a multilayer piezoelectric (electrostrictive) element, a ceramic green sheet (hereinafter, referred to as a ceramic green sheet) is used. A step of laminating and performing heat compression integration (hereinafter referred to as lamination).

For example, in a multilayer capacitor, a predetermined number of ceramic green sheets on which predetermined internal electrode patterns are printed are laminated to form a laminated body, and after laminating, cutting, degreasing and firing are performed. Manufactured through

In such a manufacturing method, as a means for preventing structural defects (delamination, cracks, etc.) from occurring in the laminated body, isostatic pressing by applying a hydrostatic pressure (hereinafter referred to as CIP). It has been known. For example, JP-A-5-21268 discloses that a ceramic laminate is fixed on a metal plate provided with an adhesive film, cut grooves are provided in the laminating direction of the ceramic laminate, and then placed in an airtight bag. In addition, there is disclosed means for vacuum-sealing and compression-molding by applying hydrostatic pressure.

However, according to the technique disclosed in Japanese Patent Application Laid-Open No. Hei 5-21268, when the hydrostatic pressure becomes 250 kgf / cm ² or more,
Since the cutting groove closes and the chips may adhere to each other,
50~250kgf / cm ² As is clear from what is described and it is necessary to limit to the an upper limit of hydrostatic pressure 250 kgf / cm ² can be applied.

As another prior art, Japanese Patent Application Laid-Open No. 7-176449 discloses a technique using a special jig provided with a frame around the ceramic green sheet laminate in order to avoid deformation of the laminate. I have. However, in Japanese Patent Application Laid-Open No. 7-176449, since a special jig provided with a frame is required, the work for putting the laminate into and out of the frame is complicated, time-consuming, and poor in workability. Also, because the frame is used, its size increases,
There is a disadvantage that the number of laminates processed at one time is reduced.

As another prior art, Japanese Patent Application Laid-Open No. 8-255728 discloses that a laminate is placed in a plastic film pack of polyethylene or the like, sealed by heat sealing in a vacuum, and then 60-85 ° C. 100-400Kg at the temperature of
A technique for performing lamination by applying a pressure of f / cm ² is disclosed. However, the technology described in JP-A-8-255728 is also
There is an upper limit of the hydrostatic pressure at which 400 kgf / cm ² can be applied.

[0008]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method by which high quality multilayer ceramic electronic components can be manufactured.

Another object of the present invention is to provide a method capable of producing a multilayer ceramic electronic component without structural defects.

[0010] Still another object of the present invention is to provide a green sheet laminate for a multilayer ceramic capacitor.
An object of the present invention is to provide a method for manufacturing a multilayer ceramic electronic component that can stack a thin laminate with a very small shape change.

Still another object of the present invention is to provide a multi-layer ceramic electronic component having stable characteristics, which can be stacked under super-pressure, has a large pressure selection range, and can select a stack pressure in accordance with product characteristics. To provide a production method that can be produced by

Still another object of the present invention is to provide a method of manufacturing a multilayer ceramic electronic component excellent in workability without using a special mold such as a frame.

[0013]

In order to solve the above-mentioned problems, a method of manufacturing a multilayer ceramic electronic component according to the present invention comprises compression-molding a laminate obtained by laminating a plurality of ceramic green sheets. I do. After disposing the laminate on a supporting substrate, it is hermetically sealed and molded under a hydrostatic pressure of 1000 kgf / cm ² or more.

As described above, after at least one surface of the laminate is fixed on the support substrate, it is hermetically sealed and subjected to pressure molding by hydrostatic pressure. No distortion or bending occurs. Moreover, since the laminate is supported by the support substrate, the shape of the laminate is stable, and the workability and yield are improved.

Further, it has been found that a high-quality multilayer ceramic electronic component free from structural defects can be manufactured by pressure molding with a hydrostatic pressure of 1000 kgf / cm ² or more, as compared with the related art. Furthermore, unlike the past, since no frame is used,
Excellent workability.

The laminate is formed of a plurality of ceramic green screens.
The stacks are laminated, and the laminate is obtained by temporary stacking.

The laminate placed on the supporting substrate may be further hermetically sealed with a laminate film or the like and subjected to vacuum processing, and the resulting vacuum package may be pressurized by CIP processing. The laminate may be wrapped with Saran Wrap (registered trademark), for example.

Preferably, an organic film is interposed between the supporting substrate and the laminate. In this case, the organic film preferably has a release agent on the surface.

[0019]

FIG. 1 is a perspective view showing one ceramic green sheet. The ceramic green sheet 1 has, for example, a plane area of 200 mm × 200 mm and a thickness of 8 μm.
And a plurality of internal electrodes 2 are formed on one surface.

FIG. 2 is a perspective view of a laminate obtained by laminating the ceramic green sheets shown in FIG. The laminated body 3 shown in FIG. 2 is configured by stacking, for example, about 300 ceramic green sheets 1 shown in FIG. The laminate 3 is made up of a required number of ceramic green screens.
After the stack 1 is stacked, for example, using a uniaxial hydraulic press,
It is desirable to pressurize at 00 kg / cm ² and pre-press.
When the pre-pressing is performed, even if the CIP processing is performed at an ultra-high pressure of 1000 kgf / cm ² or more, there is no distortion or deformation of the laminated body itself, and characteristic failure due to pattern distortion in the subsequent cutting process and firing. Occurrence of lamination or the like is sometimes prevented, and a high-quality multilayer ceramic capacitor can be manufactured. The laminate 3 may be wrapped with Saran Wrap (registered trademark) or the like.

Next, as shown in FIG. 3, the laminate 3 is arranged on the surface of the support substrate 4. In the embodiment, the support substrate 4 and
An organic film 5 is interposed between the laminate 3. As the organic film 5, a PET (polyethylene terephthalate) film can be used. In this case, the film 5 desirably has a release agent on the surface. The laminate 3 is stacked so as to be in contact with the release agent provided on the film 5.

The supporting substrate 4 is preferably of a size of, for example, 205 mm × 205 mm and a thickness of 1.5 mm for the laminate 3 having the above-mentioned size. However, if it is not distorted, the thickness may be thinner, for example, 1.5 mm to 0.5 mm.
Can be used.

Since the supporting substrate 4 is subjected to super-pressing, distortion and
It is necessary to have rigidity to prevent deformation etc.
You. Specifically, 5000 kgf / cm^Two For the hydrostatic pressure of
Be rigid enough to keep the shape change within 5%
Is desirable. The larger the shape change of the support substrate 4 is, the larger
Indeed, the laminate 3 may be greatly deformed.

Further, it is desirable that the maximum amount of distortion of the support substrate 4 be 1% or less with respect to the long axis direction with respect to a load considered to be generated in a normal operation such as process movement or vacuum sealing. When the amount of distortion of the support substrate 4 is large, delamination or cracking of the laminate 3 occurs.

Further, when the CIP processing method is performed, since the water temperature rises due to the operating heat or the like, it is preferable that the support substrate 4 be capable of maintaining the above-mentioned physical properties even at a temperature of 100 ° C. in consideration of safety. Furthermore, for economic reasons, it is desirable to use a material that is light, inexpensive and has good workability.

In order to satisfy the above conditions, the supporting substrate 4
Is made of any of metal, ceramic or hard plastic. Examples of the metal material forming the support substrate 4 include aluminum, stainless steel, iron, and the like.
Copper or an alloy thereof can be given. Ceramic materials include alumina, glass and non-oxide ceramics. Hard plastics are suitable as plastic materials. These materials are selected in consideration of the size of the laminated body, the magnitude of the pressing force, the economy, and the like.

Next, as shown in FIG. 5, the laminate of the support substrate 4, the film 5 and the laminate 3 is placed on an organic packaging film 6 of Saran Wrap (registered trademark).

Next, as illustrated in FIG. 5, the packaging film 6 is lifted up as indicated by an arrow a1 and covered with the support substrate 4, the film 5 and the laminate 3 and, as shown in FIG. The laminate of the support substrate 4, the film 5, and the laminate 3 is covered with the packaging film 6 with the packaging film 6.

Next, as shown in FIGS. 7 and 8, the periphery of the packaging film 6 is vacuum-sealed L to obtain a vacuum package 7. The packaging film 6 constituting the vacuum package 7 is actually in close contact with the support substrate 4, the film 5 and the laminate 3 by vacuum suction, and no space is formed inside the vacuum package 7. .

FIG. 9 is a schematic explanatory view showing an example of the CIP processing method according to the present invention. As shown, the CIP processing method is performed using two closed molds 8 and 9. The dies 8 and 9 include a receiving die 8 for storing water 10 serving as a pressurizing medium and a pressurizing die 9. A plurality of the vacuum packaging bodies 7 obtained through the steps of FIGS. 1 to 8 are inserted and placed together with the water 10 in the receiving die 8 and pressurized by the pressing die 9. As a result, the water pressure f1 is applied to the vacuum package 7 from all directions, and isotropic pressure molding is performed. In CIP processing, 1
Press molding with hydrostatic pressure of 000 kgf / cm ² or more.

After performing the above-described CIP processing method, the laminate 3 is taken out from the vacuum package 7 and
A cutting and firing process is performed. Thus, an electronic component is manufactured. The steps after the CIP processing method are well-known, and thus the description is omitted.

Next, in the CIP processing method, the pressing force is set to 1
^{000kgf / cm 2, 1500kgf / cm} 2, 20000kgf / c
m ² , deformation rate when changed as 30,000 kgf / cm ² ,
Table 1 shows data of thickness reduction ratio, structural defect ratio, capacitance variation, and voltage breakdown (Vb).

As shown in Table 1, according to the embodiment of the present invention, the deformation rate of one side of the laminate is reduced to 1/10 or less under the constant room temperature condition, as compared with Comparative Example 1 having no support substrate 4. and,
The rejection rate of the final multilayer capacitor is also remarkably improved. In the case of Comparative Example 1 without the support substrate 4, the deformation becomes large, and it becomes impossible to cut the multilayer capacitor to make it impossible to measure. In particular, the defect rate such as a structural defect is 1/10 or less as compared with the comparative example 2 without the CIP treatment and the CIP treatment method without the support substrate 4 (comparative example 1), and the method according to the present invention is remarkable. It turns out that an effect is obtained.

In addition, when the pressure is increased, especially in the case of an ultra-high pressure, structural defects such as delamination and non-lamination are eliminated, and the capacitance variation and voltage destruction (Vb) value associated therewith are also improved. You. That is, as shown in FIG. 10, when the pressing force is increased, the thickness of the ceramic sheet decreases, and the green sheet density increases.
Structural defects are eliminated, and the resulting capacitance variation and voltage breakdown (Vb) value are also improved. In the case of the present invention, since the support substrate 4 is used, an ultra-high pressure CIP processing method of 3000 to 5000 kgf / cm ² can be realized, and therefore, there is no structural defect, and in the case of a multilayer capacitor, an improved capacitance is achieved. Variations and voltage breakdown (Vb) values can be obtained.

[0035]

【The invention's effect】

(A) It is possible to provide a manufacturing method capable of manufacturing a high-quality multilayer ceramic electronic component. (B) It is possible to provide a method capable of manufacturing a multilayer ceramic electronic component free from structural defects. (C) It is possible to provide a method of manufacturing a multilayer ceramic electronic component that can stack a thin multilayer body with a very small shape change, such as a green sheet multilayer body for a multilayer ceramic capacitor. (D) To provide a manufacturing method capable of stacking under super-pressure, having a large pressure selection range, selecting a stack pressure in accordance with product characteristics, and manufacturing multilayer ceramic electronic components having stable characteristics at a high yield. Can be. (E) It is not necessary to use a special mold such as a frame, and a method for manufacturing a multilayer ceramic electronic component excellent in workability can be provided.

[Brief description of the drawings]

FIG. 1 is a perspective view showing one ceramic green sheet.

FIG. 2 is a perspective view of a laminate obtained by laminating the ceramic green sheets shown in FIG.

FIG. 3 is a perspective view showing a manufacturing process of the multilayer ceramic electronic component according to the present invention.

FIG. 4 is a view showing the same step as the step shown in FIG. 3;

FIG. 5 is a perspective view showing a step after the step shown in FIGS. 3 and 4.

FIG. 6 is a perspective view showing a step after the step shown in FIG. 5;

FIG. 7 is a perspective view showing a step after the step shown in FIG. 6;

FIG. 8 is a view showing the same step as the step shown in FIG. 7;

FIG. 9 is a diagram showing a CIP processing method according to the present invention.

FIG. 10 is a graph showing a relationship between a change in thickness of a ceramic green sheet and a green sheet density with respect to a pressing force.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ceramic green sheet 3 Laminated body 4 Support substrate 5 Film 6 Organic film 7 Vacuum package 8 Receiving type 9 Press type 10 Water

Claims (5)

[Claims] 1. A method for manufacturing a multilayer ceramic electronic component, comprising a step of compression-molding a laminate obtained by laminating a plurality of ceramic green sheets, wherein the laminate is disposed on a support substrate. Thereafter, this is sealed, and a method for producing a multilayer ceramic electronic component is performed by pressure molding with a hydrostatic pressure of 1000 kgf / cm ² or more. 2. The method according to claim 1, wherein the support substrate is one of a metal, a ceramic, and a hard plastic. 3. The method according to claim 1, wherein an organic film is interposed between the support substrate and the laminate. 4. The method according to claim 3, wherein the organic film has a release agent on a surface thereof. 5. The method according to claim 1, wherein the multilayer body has 50 or more layers.