JP2000290077A - Manufacturing method of multilayer ceramic electronic component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the occurrence of internal structural defects such as cracks and cracks in a multilayer ceramic electronic component such as a thin ceramic layer, a multi-layered product, or a base metal internal electrode product, and to achieve a high characteristic with little characteristic deterioration. An object of the present invention is to provide a method for manufacturing a multilayer ceramic electronic component having excellent reliability. SOLUTION: After a green chip of a multilayer ceramic electronic component is heat-treated in an atmosphere of 50 ° C to 200 ° C for at least 10 minutes or more, a temperature rising rate between 200 ° C and 600 ° C is 5 times.
The debubbling firing is performed in a gas atmosphere such as a hydrogen gas or a nitrogen gas at a rate of 0 ° C./hr or less.

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 multilayer ceramic electronic component such as a multilayer ceramic capacitor, and more particularly to a method for removing a die.

[0002]

2. Description of the Related Art Conventionally, a multilayer ceramic electronic component is heated to a predetermined temperature at a constant speed, kept at that temperature for a predetermined time to decompose and remove an organic binder used for molding, and then fired to provide a desired function. The method is taken.

[0003]

However, in order to meet market demands for higher performance and lower cost of multilayer ceramic electronic components in recent years, ceramic layers must be made thinner and more multilayered and base metals must be used for internal electrodes. Is progressing at a rapid pace.

For this reason, in the conventional debubbling firing method, structural defects such as cracks and cracks are liable to occur inside the laminate due to rapid combustion decomposition of an organic binder or a plasticizer used for molding a multilayer ceramic electronic component.

Further, in the case of using a base metal internal electrode, it is necessary to de-buy under a low oxygen partial pressure in an atmosphere such as nitrogen gas in order to prevent oxidation of the electrode material. At this time, the plasticizer generally requires more oxygen at the time of combustion decomposition than the organic binder, and is likely to remain without being sufficiently removed at the time of de-buying, so that it remains as carbon in the final sintered body. This causes a problem that it causes deterioration of the product characteristics and makes it difficult to ensure the reliability.

The present invention solves the above-mentioned conventional problems and suppresses the occurrence of structural defects such as cracks and cracks inside a multilayer ceramic electronic component, and has excellent reliability even when a base metal internal electrode is used. It is an object of the present invention to provide a method for manufacturing a laminated ceramic electronic component.

[0007]

In order to solve the above-mentioned problems, the present invention provides a laminated ceramic green chip which has been subjected to a heat treatment in an atmosphere at 50 ° C. to 200 ° C. for 10 minutes or more and then a de-built firing. It is intended to provide a method for manufacturing a multilayer ceramic electronic component.

According to this method, it is possible to prevent structural defects such as cracks and cracks generated inside the multilayer ceramic electronic component, and to obtain a highly reliable multilayer ceramic electronic component having high reliability even when a base metal internal electrode is used.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS According to the first aspect of the present invention, a laminated ceramic green chip before de-built firing is used.
After heat treatment for more than 10 minutes in the air at 0 ° C to 200 ° C,
This is a method for manufacturing a multilayer ceramic electronic component to be de-built and fired. The green chip is heat-treated in air at 50 ° C. to 200 ° C. for 10 minutes or more, so that the decomposition temperature is lower than that of the organic binder, and furthermore, the combustion decomposition Sometimes plasticizers that require a lot of oxygen can be completely decomposed and removed first, and at the same time, volatile components such as residual organic solvents can be removed. In the subsequent de-built firing, the organic binder is decomposed and removed without causing thermal strain in the multilayer ceramic green chip, and thus the residual carbon of the sintered body can be reduced.

According to a second aspect of the present invention, the laminated ceramic green chip before de-built firing is heated to 50 ° C. to 20 ° C.
After heat treatment in the air at 0 ° C. for 10 minutes or more, de-bubbling is performed in a gas atmosphere selected from among nitrogen gas, hydrogen gas, carbon dioxide gas, and water vapor, and a mixed gas atmosphere selected from two or more of these. This is a method for producing a multilayer ceramic electronic component in a plasticizer which generally requires a greater amount of oxygen during combustion than an organic binder in advance at 50 ° C.
It can be decomposed and removed by heat treatment at a temperature of 00 ° C., it can suppress rapid heat generation and can completely perform combustion decomposition. In addition to preventing the oxidative deterioration of the organic binder, the organic binder can be gradually burned and decomposed and removed without abrupt heat generation, and the residual carbon of the sintered body can be reduced.

According to a third aspect of the present invention, when the multilayer ceramic green chip is defired and fired, a 200
3. The method for manufacturing a multilayer ceramic electronic component according to claim 1, wherein the rate of temperature rise from 50 ° C. to 600 ° C. is 50 ° C./hr or less.
By performing the heat treatment of the green chip for more than one minute, the plasticizer that has a lower decomposition temperature than the organic binder and requires a large amount of oxygen during combustion decomposition can be completely decomposed and removed, and at the same time, the volatile organic solvent Components can also be removed. Then 200 ° C-6 in a gas atmosphere
By raising the temperature between 00 ° C. at a temperature rising rate of 50 ° C./hr or less, the organic binder gradually burns and decomposes without sudden heat generation, and can be more completely removed. It has the effect of reducing carbon residue.

An embodiment of the present invention will be described below with reference to a method of manufacturing a multilayer ceramic electronic component using a multilayer ceramic capacitor as a representative.

First, a slurry was prepared by mixing a dielectric material containing barium titanate as a main component, polyvinyl butyral resin as an organic binder, dibutyl phthalate as a plasticizer, and n-butyl acetate as an organic solvent in a ball mill.

Next, this slurry was formed into a green sheet having a thickness of 13 μm by a reverse roll coater method, and an electrode paste containing Ni as a main component was applied to the surface by a screen printing method to form internal electrodes. .

Next, 80 green sheets on which the internal electrodes are formed are laminated, and 10 sheets on which the electrode paste is not applied are laminated on both upper and lower surfaces of the green sheets.
It cut | disconnected after crimping | compression-bonding, and produced 2.5 mm x 1.6 mm x 1.6 mm laminated ceramic green chip.

The obtained laminated ceramic green chip has a structure in which internal electrodes are alternately exposed at every other end of the green ceramic chip at opposite ends in the longitudinal direction with a green sheet interposed therebetween.

Next, the multilayer ceramic green chips were subjected to a heat treatment using a hot air circulation type drier in the air atmosphere under the conditions shown in (Table 1).

Next, using a batch-type atmosphere firing furnace, while flowing nitrogen gas at a rate of 100 liters per minute, the temperature is 200 ° C. to 6 ° C.
The temperature was raised between 00 ° C. at the heating rate shown in (Table 1), and the temperature was maintained at 600 ° C. for 5 hours to remove the solder.

After that, the de-built laminated ceramic green chips were heated to 1300 ° C. at 100 ° C./h while flowing nitrogen gas at a rate of 50 liters per minute using a batch type atmosphere firing furnace.
r The temperature was raised at a rate of temperature increase, and the temperature was maintained at 1300 ° C. for 2 hours for firing.

At both ends of the obtained sintered body where the internal electrodes were exposed, the internal electrodes were electrically connected to each other to form external electrodes, thereby completing a multilayer ceramic capacitor.

Regarding the multilayer ceramic capacitor,
The occurrence of internal structural defects and the insulation resistance value before and after applying DC 32 V for 250 hours in a thermostat at 125 ° C. as a reliability accelerated life test were measured, and the results are also shown in (Table 1). The structural defects shown in Table 1 were 500 defects each.
The number of occurrences in each sample, and the initial value for insulation resistance failure is 1
The number of 50 articles of ⁰⁹ or more deteriorated to 10 ⁷ or less after the test was shown. The samples marked with # are comparative examples outside the scope of the present invention.

[0022]

[Table 1]

As shown in Table 1, in the multilayer ceramic capacitor of the present embodiment, the number of internal structural defects such as cracks and cracks in the multilayer ceramic capacitor is significantly reduced as compared with the comparative example, and the multilayer ceramic capacitor is accelerated. It can be seen that even in the life test, the deterioration of the insulation resistance is extremely reduced. From these results, it is clear that the present invention is an effective means for improving the characteristics of the multilayer ceramic capacitor. In particular, after performing heat treatment at a temperature of 50 to 200 ° C. for at least 10 minutes or more before de-buying, a temperature of 200 ° C. to 600
When the temperature is raised between 50 ° C and 50 ° C / hr or less,
The number of occurrences of internal structural defects and deterioration of insulation resistance was minimized, which was favorable.

Further, in the case of the base metal internal electrode product, the debubbling firing is performed in a gas atmosphere such as nitrogen gas, hydrogen gas, carbon dioxide gas, water vapor, or a mixed gas atmosphere selected from two or more of these. The effect of the heat treatment is remarkable.

In this embodiment, a multilayer ceramic capacitor having a base metal Ni as an internal electrode is described.
It is not limited to this, but Pd and A other than base metals
The same effect can be obtained by applying the present invention to a multilayer ceramic capacitor or other electronic component using a g-Pd alloy or the like for an internal electrode, such as a multilayer actuator or a multilayer varistor. Furthermore, although the atmosphere for de-buying has been described only in the nitrogen gas atmosphere, it has been confirmed that similar results can be obtained even in a hydrogen gas, carbon dioxide gas, or steam atmosphere. Further, similar effects can be obtained even in other atmospheres including an air atmosphere, depending on the applied multilayer ceramic electronic component and the material of the internal electrode used.

[0026]

As described above, according to the method for manufacturing a multilayer ceramic electronic component of the present invention, the multilayer ceramic green chip before de-built firing is heat-treated in the air at 50 ° C. to 200 ° C. for 10 minutes or more, and then de-built firing. By doing so, first, the plasticizer used for molding of the laminated ceramic green chip can be completely removed by combustion without sudden heat generation during the heat treatment, and the plasticizer can be removed during the subsequent debuiling of the organic binder. It can be completely burned and decomposed and removed without sudden heat generation, and the final sintered body has reduced internal structural defects such as cracks and cracks and residual carbon, and has high reliability with little deterioration of product characteristics. This has the effect that it becomes possible to provide a multilayer ceramic electronic component having the same.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Masako Murao 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture F-term in Matsushita Electric Industrial Co., Ltd. 4G031 AA06 AA11 BA09 CA03 GA07 GA08 GA11 5E001 AB03 AC09 AC10 AE02 AE03 AF06 AH01 AH05 AH06 AH08 AH09 AJ01 AJ02

Claims (3)

[Claims] 1. A method for manufacturing a multilayer ceramic electronic component, comprising: subjecting a multilayer ceramic green chip before de-built firing to heat treatment in an atmosphere at 50 ° C. to 200 ° C. for 10 minutes or more, and then de-builing and firing. 2. The multilayer ceramic green chip before baking-off firing is heat-treated in an atmosphere at 50 ° C. to 200 ° C. for 10 minutes or more, and baking-off firing is selected from nitrogen gas, hydrogen gas, carbon dioxide gas, and water vapor. Of manufacturing a multilayer ceramic electronic component in a mixed gas atmosphere and a mixed gas atmosphere selected from two or more of these. 3. When the multilayer ceramic green chip is subjected to debubbling and firing, the temperature is raised from 200 ° C. to 600 ° C. at a rate of 50 ° C.
The method for manufacturing a multilayer ceramic electronic component according to claim 1 or 2, wherein the ratio is not more than / hr.