JPH10112417A - Laminated electronic component and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent separation of a back-side electrode from a layered product and make possible realization of a higher density. SOLUTION: A laminated ceramic capacitor 10 includes a layered product 11, and an surface-side electrode 12 and a back-side electrode 13 as external electrodes. In the layered product 11, a plurality of ceramic raw sheets 15a to 15e are stacked in a state that internal electrodes 14a to 14d to be circuit elements are provided between the ceramic raw sheets. The surface-side electrode 12 is provided on a surface 11a as another main surface of the layered product 11, and the back-side electrode 13 is provided on a surface 11b as one main surface of the layered product 11. In the ceramic raw sheets 15a to 15e, connection means penetrating these sheets in the direction of thickness, for example, via holes 16a, 16b, are formed. The via holes 16a, 16b are used for connecting the surface-side electrode 12 with the internal electrodes 14b, 14d, and for connecting the back-side electrode 13 with the internal electrodes 14a, 14c, respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multilayer ceramic electronic component and a method of manufacturing the same, and more particularly, to a multilayer ceramic electronic component in which internal electrodes to be circuit elements are disposed inside and external electrodes are disposed on both main surfaces. It relates to the manufacturing method.

[0002]

2. Description of the Related Art A multilayer ceramic electronic component includes a multilayer ceramic capacitor, a multilayer ceramic inductor, a multilayer ceramic resistor, and a multilayer ceramic composite component in which a plurality of these elements are integrated. FIG. 3 shows a cross-sectional view of the multilayer ceramic capacitor 1 as a typical example of such an electronic component. The multilayer ceramic capacitor 1 has internal electrodes 3 a to 3 d inside the multilayer body 2, a surface electrode 4 as an external electrode on the front surface 2 a of the multilayer body 2, and a back electrode 5 as an external electrode on the back surface 2 b of the multilayer body 2. Prepare. On this occasion,
The internal electrodes 3b, 3d and the surface electrode 4 are connected to via holes 6a.
Thus, the internal electrodes 3a, 3c and the back electrode 5 are
b.

FIG. 4 shows a manufacturing process diagram for forming the multilayer ceramic capacitor 1. First, in the step (a), a dielectric ceramic powder and an organic binder are mixed to form a slurry, and a slurry casting method such as a doctor blade method or a reverse coating method is used to form a slurry.
To obtain the raw ceramic sheets 7a to 7e. And
In the step (b), the ceramic raw sheets 7a to 7
In e, via holes 6a and 6b penetrating the raw ceramic sheets 7a to 7e are formed by punching or the like in order to enable electrical conduction in the thickness direction of the sheet.

[0004] Next, as a step (c), circuit elements (not shown) are formed on the surfaces of the ceramic raw sheets 7a to 7e by screen printing or roll transfer using a conductive paste such as palladium. Internal electrodes 3a to be
3d or the surface electrode 4 as an external electrode is printed. Then, as a step (d), the green ceramic sheets 7a to 7e are stacked.

[0005] Next, as a step (e), the laminated body 2 is obtained by placing the flat plate between two parallel flat plates of a pressing machine (not shown) and moving the flat plates from above and below and pressing them. After that, the ceramic raw sheet 7 constituting the laminate 2
In order to sinter a to 7e, the laminate 2 is fired. At this time, the internal electrodes 3a to 3d and the surface electrode 4 are fired simultaneously with the green ceramic sheets 7a to 7e. And
In the step (f), a conductive coating film is formed on the back surface 2b of the laminate 2 by using a conductive paste such as palladium by a screen printing method or a roll transfer method, and is baked to perform a back surface electrode as an external electrode. 5 is formed. At this time, the front surface electrode 4 and the back surface electrode 5 are connected to the internal electrodes 3a to 3d by via holes 6a and 6b.

Incidentally, the steps (e) and (f) are reversed, and after the laminate 2 is obtained by crimping, the laminate 2
The back electrode 5 is formed on the back surface of the substrate, and thereafter, the sintering of the ceramic green sheets 7a to 7e constituting the laminate 2 and the back electrode 5 are performed.
In some cases, firing is also performed as a baking process.

[0007]

However, in the above-mentioned multilayer ceramic electronic component, since the internal electrode and the back electrode cannot be simultaneously printed on both sides of the ceramic green sheet, a plurality of ceramics on which the surface electrode or the internal electrode is printed are formed. After producing a laminate formed by pressing and firing a green sheet, a back electrode must be provided on the back surface of the laminate by printing and baking.
Therefore, the step of providing the back electrode is performed after the step of pressing the laminate, and as a result, the back electrode cannot be cut into the back surface of the laminate.

Therefore, the plating solution may enter between the back surface of the laminate and the back surface electrode during the acid treatment such as plating,
There is a problem that the back electrode is easily peeled off from the laminate due to invasion of the plating solution. Further, when a force is applied to the edge of the back electrode, there is a problem that the back electrode is easily peeled from the laminate.

Further, when a back electrode is formed on the back surface of the laminate after firing the laminate, the laminate has a dimensional variation of about ± 0.6% due to shrinkage during firing.
Deviation occurs between the position of the back electrode and the position of the via hole. Therefore, it is necessary to increase the area of the back electrode, which causes a problem that the increase in the density is hindered. In addition, since unevenness of the via hole is generated on the back surface of the laminate after firing, there is a problem that the back electrode formed by printing is blurred, which hinders high density. Further, there are cases where two firing steps are required, a step of firing the laminate and a step of firing the back electrode, and in this case, there is a problem that the cost is increased.

In addition, after the laminate is pressed, that is, before firing, a back electrode is formed on the back surface of the laminate, and the step of firing the laminate and the step of firing the back electrode are performed simultaneously. Since the laminate extends by about 0.1 to 0.8%, a deviation occurs between the position of the back electrode and the position of the via hole. Therefore, it is necessary to increase the area of the back electrode, which causes a problem that the increase in the density is hindered.

SUMMARY OF THE INVENTION The present invention has been made to solve such problems, and provides a multilayer ceramic electronic component capable of achieving high density without peeling off the back electrode from the laminate and a method of manufacturing the same. The purpose is to:

[0012]

In order to solve the above-mentioned problems, a multilayer ceramic electronic component according to the present invention comprises a plurality of ceramic green sheets laminated with internal electrodes to be circuit elements interposed. A laminate having an opposing main surface and a side surface connecting the main surfaces, and a back electrode provided on a back surface that is one main surface of the laminate, wherein the back electrode is formed of the laminate It is characterized by being cut into the back.

Further, in the method of manufacturing a multilayer ceramic electronic component according to the present invention, a plurality of raw ceramic sheets and a carrier film are prepared, and an internal electrode and an internal electrode are formed on one main surface of at least one of the plurality of raw ceramic sheets. After forming a metal paste film to be a back electrode on one main surface of the carrier film, the plurality of green ceramic sheets are stacked on one main surface side of the carrier film, and these are pressed. Then, the carrier film is removed.

According to the multilayer ceramic electronic component of the present invention, since the back surface electrode is cut into the back surface of the laminate,
It is possible to prevent the plating solution from entering between the back surface of the laminate and the back surface electrode during acid treatment such as plating.

Further, according to the method for manufacturing a multilayer ceramic electronic component of the present invention, since the green ceramic sheet, the internal electrode and the back electrode are simultaneously pressed and fired, the position of the back electrode and the position of the via hole are set as designed. Can be matched.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a cross-sectional view of one embodiment according to the multilayer ceramic electronic component of the present invention. Reference numeral 10 denotes a multilayer ceramic capacitor which is a typical example of a multilayer ceramic electronic component.

The multilayer ceramic capacitor 10 includes a multilayer body 11, front electrodes 12 and back electrodes 13 which are external electrodes.
It is composed of In the laminate 11, a plurality of raw ceramic sheets 15a to 15e are laminated with internal electrodes 14a to 14d to be circuit elements interposed therebetween.

Here, the front surface electrode 12 is provided on the front surface 11a which is the other main surface of the multilayer body 11, and the back electrode 13 is provided on the back surface 11b which is one main surface of the multilayer body 11. Alternatively, a part of the back surface 11b is bitten.

The ceramic raw sheets 15a to 15
e, connection means, for example, via holes 16a and 16b are formed through the thickness direction thereof.
16b connects the surface electrode 12 and the internal electrodes 14b and 14d,
Alternatively, it is used to connect the back electrode 13 to the internal electrodes 14a and 14c.

Next, a manufacturing method for obtaining the multilayer ceramic capacitor 10 will be described with reference to FIG. First,
As a step (a), a slurry is formed by mixing a dielectric ceramic powder and an organic binder, and the raw ceramic sheets 15a to 15e having a thickness of more than 10 μm are formed by a slit casting method such as a doctor blade method or a reverse coating method.
Get. In the step (b), the ceramic raw sheets 15a to 15e are electrically connected to the ceramic raw sheets 15a to 15e in the thickness direction of the sheets.
Via holes 16a and 16b penetrating through e are formed by punching or the like.

Next, in the step (c), the surface electrodes 12 or the internal electrodes 14a to 14d to become circuit elements (not shown) are formed by screen printing or roll transfer using a conductive paste such as palladium. Is printed on one main surface of the ceramic raw sheets 15a to 15e. Then, as a step (d), a back surface electrode 13 is printed on one main surface by a screen printing method or a roll transfer method using a conductive paste such as palladium, for example, one main surface of a plastic film 17. Side (the side on which the back electrode 13 is formed)
The ceramic raw sheets 15a to 15e having 4a to 14d printed on one main surface are stacked.

Next, as a step (e), the laminate is placed between two parallel flat plates of a pressing machine (not shown), and these flat plates are moved from above and below and pressed to obtain a laminate 11. Then, as a step (f), after the plastic film 17 is peeled off from the laminate 11, the front surface electrode 12 is on the other main surface, the back electrode 13 is on the one main surface, and the internal electrode is inside. Ceramic raw sheets 15a to 15 constituting the laminated body 11 on which 14a to 14d are formed
It is fired to sinter e. At this time, the surface electrode 1
2. The back electrode 13 and the internal electrodes 14a to 14d are fired simultaneously with the green ceramic sheets 15a to 15e, and the front electrode 12 and the back electrode 13 are connected to the via holes 16a, 16
b connects to the internal electrodes 14a to 14d. Also,
Part of the front surface electrode 12 and the back surface electrode 13 bites into the front surface 11a and the back surface 11b of the multilayer body 11 by the pressure bonding process. Through the above manufacturing steps, the multilayer ceramic capacitor 10 is manufactured.

As described above, according to the multilayer ceramic capacitor of the present embodiment, since the back surface electrode is cut into the back surface of the laminate, the plating solution is applied between the back surface of the laminate and the back surface electrode during an acid treatment such as plating. Therefore, it is possible to prevent the back electrode from peeling off from the laminate. Further, even when a force is applied to the edge of the back electrode, the back electrode cuts into the back surface of the laminate, so that the back electrode can be prevented from peeling off from the laminate.

Further, even if the thickness of the back electrode is increased to reduce the resistance, the smoothness of the back electrode is not deteriorated because the back electrode is formed on the back surface of the laminate by the pressure bonding step. Therefore, when high frequency is used, the resistance of the back electrode can be reduced, and the characteristics of the multilayer ceramic capacitor can be improved.

In addition, since unevenness of the via hole cannot be formed on the back surface of the laminate after firing, the back surface of the laminate becomes smooth and the back electrode does not bleed. Therefore, since the density of the back electrode can be increased, the size of the multilayer ceramic electronic component can be reduced.

Further, according to the method of manufacturing a multilayer ceramic capacitor of the present embodiment, a laminate obtained by stacking a ceramic raw sheet provided with a front electrode or an internal electrode on a plastic film provided with a back electrode is pressure-bonded. Then, since the plastic film is peeled off from the laminate and fired, the back electrode can be cut into the back surface of the laminate, and at the same time, the position of the back electrode and the position of the via hole can be matched as designed. . Accordingly, the density of the back electrode can be increased, and the size of the multilayer ceramic capacitor can be reduced.

In addition, since the back electrode is crushed during crimping,
The back electrode becomes denser, and the resistance of the back electrode can be reduced.

Further, since the step of firing the laminated body and the step of firing the back electrode are performed simultaneously, the production can be performed in one firing step. Therefore, the manufacturing cost and the manufacturing process can be reduced.

In this embodiment, the case of individually manufacturing the multilayer ceramic capacitors has been described. However, the mother ceramic raw sheets are stacked to form a mother laminate, and the mother laminate is cut to obtain a laminate. A ceramic capacitor may be manufactured. In this case,
Since a plurality of multilayer ceramic capacitors can be manufactured in one process, the manufacturing cost can be further reduced.

Also, the case where the connection means between the front electrode and the internal electrode and between the back electrode and the internal electrode is a via hole has been described. However, a through hole, an end face electrode, or a combination thereof may be used.

Further, the case where the laminate is fired after the plastic film is peeled off from the laminate has been described. However, when firing the laminate, the plastic film may be removed by firing.

Further, the case where a part of the back electrode is cut into the back surface of the laminate has been described, but all of the back electrode may be cut into the back surface of the laminate.

Further, the case of the multilayer ceramic capacitor has been described as an example,
It goes without saying that the present invention can be applied to other multilayer ceramic electronic components such as a multilayer ceramic resistor or a multilayer ceramic composite component in which a plurality of these elements are integrated.

[0034]

According to the multilayer ceramic electronic component of the first aspect, since the back electrode is cut into the back surface of the laminate, a plating solution is applied between the back surface of the laminate and the back electrode during an acid treatment such as plating. To prevent intrusion into
It is possible to prevent the back electrode from peeling off from the laminate. Also, when a force is applied to the edge of the back electrode,
It is possible to prevent the back electrode from peeling off from the laminate.

Further, even if the thickness of the back electrode is increased in order to reduce the resistance, the back electrode is formed on the back surface of the laminate by the pressure bonding step, so that the smoothness of the back electrode does not deteriorate. Therefore, when high frequency is used, the resistance of the back electrode can be reduced, and the characteristics of the multilayer ceramic capacitor can be improved.

Further, since no via holes are formed on the back surface of the laminate after firing, the back surface of the laminate becomes smooth and the back electrode does not bleed. Therefore, since the density of the back electrode can be increased, the size of the multilayer ceramic electronic component can be reduced.

According to the method for manufacturing a laminated ceramic electronic component of the present invention, a laminate obtained by stacking a ceramic raw sheet provided with a front electrode or an internal electrode on a plastic film provided with a back electrode is pressed. Since the plastic film is peeled off from the laminate and fired, the back electrode can be cut into the back surface of the laminate, and the position of the back electrode can be matched with the position of the via hole as designed. Therefore, the density of the back electrode can be increased, and the size of the multilayer ceramic electronic component can be reduced.

In addition, since the back electrode is crushed at the time of pressure bonding,
The back electrode becomes denser, and the resistance of the back electrode can be reduced.

Further, since the step of firing the laminated body and the step of firing the back electrode are performed simultaneously, the production can be performed in a single firing step. Therefore, the manufacturing cost and the manufacturing process can be reduced.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of one embodiment of the multilayer ceramic electronic component of the present invention.

FIG. 2 is a manufacturing process diagram for obtaining the multilayer ceramic electronic component shown in FIG.

FIG. 3 is a cross-sectional view showing a conventional multilayer ceramic electronic component.

4 is a manufacturing process diagram for obtaining the multilayer ceramic electronic component shown in FIG.

[Description of Reference Numerals] 10 laminated ceramic electronic component 11 laminated body 11a other main surface (front surface) 11b one main surface (back surface) 13 back surface electrodes 14a to 14d internal electrodes 15a to 15e ceramic raw sheet 17 carrier film (plastic film)

Claims (2)

[Claims] A plurality of ceramic green sheets are laminated with an internal electrode to be a circuit element interposed therebetween,
A laminate having an opposing main surface and a side surface connecting the main surfaces, and a back electrode provided on a back surface that is one main surface of the laminate, wherein the back electrode is a back surface of the laminate. Multilayer ceramic electronic components characterized by being cut into 2. A plurality of ceramic raw sheets and a carrier film are prepared, and a metal paste film to be an internal electrode is formed on one main surface of at least one of the plurality of ceramic raw sheets, and the metal paste film is formed on one side of the carrier film. After forming a metal paste film to be a back electrode on the main surface, the plurality of green ceramic sheets are stacked on one main surface side of the carrier film, these are pressed, and then the carrier film is removed. The method for manufacturing a multilayer ceramic electronic component according to claim 1.