JPS6047413A - Method of producing laminar ceramic condenser - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] Misfire F3A relates to a method for manufacturing a multilayer ceramic capacitor, and in particular to a method for forming internal electrodes on a green sheet.

(Background Art) Generally, this type of multilayer ceramic capacitor is manufactured as follows, for example: First, the thickness is 100 to 20 mm.
0μm green sheet (protective sheet)? Store in formwork. Next, the thickness of the inner electrode 7 having a predetermined pattern on the surface is 30 to 60/! All the green sheets (ceramic layers) of Am are sequentially stored in a mold. Continue to have a thickness of 10
All green sheets (bonron sheets) of 0 to 200 μm are stored.

In this state, all of the green sheets are pressed by a pressing body to integrate the green seeds and the internal electrodes.

Next, vertically and horizontally vc Ill+
ii Next, cut and chip. Thereafter, the chip is completely fired and external electrodes are completely formed on both ends, thereby obtaining a multilayer ceramic capacitor.

By the way, internal electrodes with a thickness of about 5 to 10 μm are formed by screen printing on the surface of the green sheet that makes up the entire ceramic layer using a conductive paste 2 containing all palladium and silver. When stacked for pressure integration, there is a tendency for some gaps to be formed between the grease sheets in areas where internal electrodes are not formed.

Therefore, if the laminated Green Sea) is pressed with the entire pressing body, undesired strain or deformation will occur inside the laminated body, and warping, cracking, etc. will easily occur during firing. This causes problems in characteristics such as a decrease in capacitance and loss of moisture resistance.

In particular, this tendency becomes noticeable when the number of stacked green sheets is large, or when the thickness of the green sheets becomes thinner due to the miniaturization of multilayer ceramic capacitors and the use of sub-layers.

[Disclosure of the invention]

Therefore, an object of the present invention is to provide a method for manufacturing a multilayer ceramic capacitor that can completely eliminate the gaps between the green sheets in the laminated state before pressing, and can reduce all defects in characteristics caused by pressing and firing operations. There is a particular thing.

The feature of the present invention is that the inner S electrode is set at a predetermined turn. Before all of the formed green sheets are appropriately laminated and integrated under pressure, recesses of a certain depth are formed on the surface of the green sheets in a pattern corresponding to the internal electrodes, and the inner FjI5 electrodes are placed in the recesses. The goal is to form it so that it is almost flush with the entire green sheet.

According to this invention, the internal electrodes are formed in the concave portions of a certain depth formed in the green sheets so as to be almost flush with the green sheets, so even if all the green sheets are stacked, they do not overlap each other. No gap is formed between them. For this reason, even if a large number of laminated green sheets or a thin green sheet is all laminated under pressure and fired, warping and cracking are less likely to occur, and deterioration of properties caused by this can be reduced.

[BEST MODE 3 FOR CARRYING OUT THE INVENTION Next, an embodiment of the present invention will be described with reference to FIGS. 1 to 5'ft.

First, as shown in Figure 1, ceramic powder is prepared.

Thickness of 30 to 60 mm with binder and solvent 7.
/'m Gree>・Sheet 1 is completely formed. After drying, recesses 2 having a depth of approximately 5 to 10 μm are formed on the surface thereof in a pattern corresponding to internal electrodes to be described later. still,
The recessed portion 2 is formed by pressing a pressing member corresponding to the rotation of the internal electrode.

Next, as shown in Fig. 2, the depression F! The entire internal electrode 3 is formed on f52 so that its surface is substantially flush with the surface of the green sheet 1. Next, as shown in Figure 3,
A plurality of green sheets 1 are laminated on a green sheet (protective sheet) 4 having a thickness of 100 to 200 μm. Furthermore, the thickness is 100~20'O/'' on top of the green sheet 1.
Layer 5 green sheets (protective sheets) in the entire tank. In this state, press with all pressing members (green sea). Through this operation, the green sheet and internal electrodes are integrated under pressure. Then, by cutting the entire laminate along the dot-dashed line, it is made into chips as shown in FIG. 4.

Next, after firing this chip, the external electrode 6.6'? ! : By forming a multilayer ceramic capacitor, a multilayer ceramic capacitor can be obtained.

According to this embodiment, the internal electrodes 3 are formed in the recesses 2 previously formed in the green sheet 1 so as to be substantially flush with the surface of the green sheet 1.
No gaps are formed between them when they are laminated. For this reason, even if the entire group of green sheets is pressed by the pressing body,
There is no possibility of undesired distortion remaining inside the laminate, and warpage occurs during firing.

Cracks can be reduced.

In particular, the thickness of 1 Green Sea) 1 is 20 pm, and the internal electrode 3
When the thickness is 8 μm, there is more warpage than in the conventional method.

Characteristic deterioration caused by cracks was reduced in all cattle.

In the present invention, the thickness and number of layers of the green sheets and internal electrodes can be changed as appropriate. Further, the number of internal electrodes formed on the green sheet can be one or more at the same time.

Simple explanatory drawings of the surfaces are explanatory drawings of the method of the present invention, in which Fig. 1 is a side sectional view of the green sheet, Fig. 2 is a side sectional view showing the entire state of formation of internal electrodes, and Fig. 3 is a side sectional view of the green sheet. FIG. 4 is a side sectional view showing the laminated structure M'', FIG. 4 is a side sectional view in a chip state, and FIG. 5 is a side sectional view in a completed state.

In the figure, 1 is a green sheet, 2 is a recessed part, and 3 is an internal electrode.

Claims (1)

[Claims] Before all the green sheets formed in a predetermined pattern are laminated as appropriate and integrated under pressure, recesses of a certain depth are formed on the surface of the green sheets in a pattern corresponding to the internal electrodes. 1. A method for manufacturing a multilayer ceramic capacitor, characterized in that an internal electrode is formed in the recessed portion so as to be substantially flush with the entire green sheet.