JP2003217968A - Manufacturing method for stacked electronic component - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stacked electronic component of high reliability, where an internal electrode is formed with accuracy. <P>SOLUTION: A ceramics paste is gravure-printed on the surface of a long carrier film 10, and then it is dried to form a step-eliminating ceramics pattern 3. A conductive paste is gravure-printed in a frame formed by the step- eliminating ceramics pattern 3 and is dried to form an internal electrode pattern 2. Then, a ceramics slurry is applied on the surface of the layer formed by the pattern, to form a ceramics green sheet 1. A composite sheet 4, being a double layer thus formed, is stacked and crimped to form a laminate, which is cut into a prescribed shape and then sintered to form element bodies. An external electrode is provided on the outer surface of the element body, to form a stacked electronic component. <P>COPYRIGHT: (C)2003,JPO

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 laminated electronic component, and more particularly to a method for manufacturing a laminated electronic component in which an internal electrode pattern and a pattern for eliminating step difference are formed by a gravure printing method.

[0002]

2. Description of the Related Art A monolithic ceramic capacitor, which is a monolithic electronic component, has a large number of ceramic layers, internal electrodes arranged between the ceramic layers, and one end of which is alternately exposed on opposite side surfaces, and the other internal electrodes are provided on the opposite side surfaces. And a pair of external electrodes formed.

At present, in such a monolithic ceramic capacitor, miniaturization and increase in capacity are progressing, and accordingly, thinning of the ceramic layer and internal electrodes is required.

The ceramic layers and internal electrodes of a conventional monolithic ceramic capacitor are formed as follows.
First, a ceramic slurry composed of a ceramic powder and an organic binder is applied onto a carrier film and dried to form a ceramic green sheet which becomes a ceramic layer. Next, a conductive paste and a ceramic paste are screen-printed on the surface of the ceramic green sheet and dried to form an internal electrode pattern and a step-eliminating ceramic pattern. The two-layer composite sheet formed in such a step is peeled from the carrier film, a predetermined number of layers are laminated, and pressure bonding is performed to integrate them to form a laminated body. After that, the laminated body is cut in the thickness direction to form individual element bodies, which are then sintered, and a pair of external electrodes are applied and sintered on the end faces of the element bodies so as to be electrically connected to the internal electrodes. Form.

However, in such a screen printing method, since the paste is printed from the opening of the screen printing plate, the paste is formed at least by the thickness of the screen printing plate. At present, the thinnest thickness is about 2 to 3 μm. As a result, it becomes difficult to reduce the thickness of the monolithic ceramic capacitor.

On the other hand, as another method for forming the internal electrode pattern and the step-resolving ceramic pattern, there is a method using gravure printing. In the gravure printing method, a ceramic slurry is applied to the surface of a carrier film that is long in the transport direction and dried to form a ceramic green sheet, as described above. Next, the surface of the ceramic green sheet on the carrier film is brought into contact with a gravure roll having a recess of a predetermined shape filled with a conductive paste, and the conductive paste is transferred. Similarly, the ceramic paste is transferred, and the conductive paste and the ceramic paste are dried to form an internal electrode pattern and a step-eliminating ceramic pattern. In this way, the ceramic green sheet having the internal electrode pattern and the pattern for eliminating the step difference formed on the surface is peeled from the carrier film, and laminated and pressure-bonded as described above to form a laminated body. Each element body is formed by cutting this laminated body in the thickness direction, and external electrodes are provided on each element to form a laminated ceramic capacitor. As described above, when the gravure printing is used, the thickness of the internal electrode pattern and the step-eliminating ceramic pattern can be set to about 1 μm. Therefore, it is possible to reduce the thickness of the laminated ceramic capacitor.

JP-A-8-250370 and JP-A-11-8156 have been devised and disclosed as improved inventions of the method of forming the internal electrode pattern and the pattern for eliminating step difference by such gravure printing.

In the invention of (1), a ceramic green sheet is formed on the carrier film by gravure printing, and the internal electrode pattern and the step-eliminating ceramic pattern are gravure printed on the surface of the ceramic green sheet and dried. Formed by. By repeating this step at least once, a composite sheet having two or more layers is formed on the carrier film. This composite sheet is further stacked and pressure-bonded to form a laminate. This laminated body is cut and fired in the thickness direction to form individual bodies, each of which is provided with an external electrode to form a laminated ceramic capacitor.

In the invention of (1), after the internal electrode pattern is formed on the carrier film by gravure printing, the step-resolving ceramic pattern is formed. A composite sheet is formed by applying a ceramic slurry to the upper surface of this layer. The composite sheet is pressure-bonded to another composite sheet similarly formed with the carrier film attached, and the carrier film is peeled off after the pressure-bonding. By repeating such a process, a laminated body is formed. This laminated body is cut and fired in the thickness direction to form individual bodies, each of which is provided with an external electrode to form a laminated ceramic capacitor.

[0010]

However, in the conventional method for manufacturing a laminated electronic component as described above, there are the following problems to be solved.

In the manufacturing method described in (1), after printing the ceramic slurry that becomes the ceramic green sheet, first, the conductive paste that becomes the internal electrode pattern is printed, and then the ceramic paste that becomes the step eliminating ceramic pattern is printed. Then, the patterned conductive paste and ceramic paste are dried to form an internal electrode pattern and a step-eliminating ceramic pattern, respectively. Therefore, as shown in FIG. 6, bleeding occurs in the internal electrode pattern.

FIG. 6 is an enlarged partial sectional view of a laminated body of a laminated ceramic capacitor. In FIG. 6, 1 is a ceramic green sheet, 2 is an internal electrode pattern, 3 is a pattern for eliminating a step difference ceramic, 4 is a composite sheet, and 20 is a blur of an internal electrode pattern. As shown in FIG. 6, when the bleeding 20 occurs in the internal electrode pattern 2, the level difference eliminating ceramic pattern 3 is formed on the bleeding 20 of the internal electrode pattern 2. When the composite sheet 4 including the internal electrode pattern 2 and the pattern 3 for eliminating step difference and the ceramic green sheet 1 is laminated to form a laminated ceramic capacitor, the internal electrode area is increased by the bleeding. There will be something different from the designed capacity. Further, when the bleeding range is widened, the space between the adjacent internal electrode patterns is narrowed, which may cause insulation resistance failure, or when bleeding further spreads, a short circuit may occur.

Further, after printing the ceramic slurry serving as the ceramic green sheet, the conductive paste serving as the internal electrode pattern, and the ceramic paste serving as the step eliminating ceramic pattern, they are simultaneously dried. Therefore, the conductive paste easily flows before drying,
Bleeding becomes severe.

Also in the manufacturing method shown in FIG. 7, bleeding occurs in the internal electrode pattern as shown in FIG. FIG. 7 is a side sectional view showing the internal electrode pattern 2, the step-resolving ceramic pattern 3, the ceramic green sheet 1, and the composite sheet 4 provided on the carrier film 10, and 20 is a blur of the internal electrode pattern 2. is there. Figure 7
As shown in (1), the conductive paste is first printed on the surface of the carrier film 10, and then the ceramic paste is printed. After that, a ceramic slurry is applied to form a composite sheet 4 including the internal electrode pattern 2, the step-resolving ceramic pattern 3, and the ceramic green sheet 1. In this manufacturing method, the bleeding 20 of the internal electrode pattern 2 occurs on the carrier film. When such a two-layer composite sheet 4 is laminated to form a laminate, when the two-layer composite sheet 4 is peeled from the carrier film 10, a problem as shown in FIG. 8 occurs. FIG. 8 is a view showing a state in which the two-layer sheet is peeled off from the carrier film, 1 is a ceramic green sheet, 2 is an internal electrode pattern, 3 is a pattern for eliminating step difference, 4 is a composite sheet, 20 is an internal electrode. Bleeding of the pattern, 21 is the peeling remaining portion of the internal electrode pattern 2, 22 is the internal electrode pattern 2
It is a chipped part. Usually, the surface of the carrier film 10 is subjected to a predetermined process so that the pattern 3 for level difference eliminating ceramics is easily peeled off. However, the composition for the pattern 3 for level difference eliminating ceramics such as the internal electrode pattern 2 is different. The peeling effect is hard to work against. Therefore, when the internal electrode pattern 2 is peeled off, a defect such as the internal electrode pattern 2 partially remaining on the carrier film 10 is likely to occur.

As shown in FIG. 8, since the end portion of the internal electrode pattern 2 is a very thin film due to the bleeding 20, the peeling becomes more difficult, and the peeling residual portion 21 of the internal electrode pattern 2 and the chipped portion 22 accompanied therewith. It tends to occur.

In order to suppress such a defect, it is possible to configure the composition so that the peel strengths of the internal electrode pattern 2 and the step eliminating ceramic pattern 3 are matched. However, each composition is limited, and the degree of freedom in design is reduced.

An object of the present invention is to provide a method for manufacturing a laminated electronic component which can form an internal electrode with high accuracy and has high reliability.

[0018]

According to the present invention, a step-resolving ceramic pattern is formed on a surface of a carrier film by gravure-printing a ceramic paste, and then a conductive paste is applied to a non-forming portion of the step-resolving ceramic pattern. An internal electrode is formed by gravure printing, a ceramic slurry is applied to the surface of a layer composed of a step-eliminating ceramic pattern and an internal electrode pattern to form a ceramic green sheet, and a composite sheet is formed. By laminating, a laminated electronic component is manufactured.

Further, according to the present invention, a ceramic slurry is applied to the surface of a carrier film to form a ceramic green sheet, and a ceramic paste is gravure-printed on the surface of the ceramic green sheet to form a pattern for eliminating step difference. After that, an internal electrode pattern is formed by gravure-printing a conductive paste on the non-formation portion of the step-eliminating ceramic pattern to form a composite sheet, and the composite sheet is laminated to manufacture a laminated electronic component.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A method of manufacturing a laminated electronic component according to a first embodiment will be described with reference to FIGS. FIG. 1 is a conceptual diagram of a gravure printing process for forming the ceramic pattern 3 and the internal electrode pattern 2. In FIG. 1, 10 is a ceramic green sheet 1 on the surface.
A carrier film on which the carrier film 10 is formed, 52 is a tension roll that conveys the carrier film 10, and 53a and 53b are
Ceramic paste 31 and conductive paste 2 respectively
1 is a gravure roll, 54a and 54b are impression cylinders that assist the gravure rolls 53a and 53b, 55a is a ceramic paste tank, 55b is a conductive paste tank, 56a,
56b is a doctor blade for removing unnecessary ceramic paste 31 and conductive paste 21, 57a, 57
Reference numeral b denotes a drying furnace for drying the ceramic paste 31 and the conductive paste 21, respectively.

FIG. 2 is a sectional view showing the process of forming the composite sheet, and FIG. 3 is a partial external perspective view thereof. In FIGS. 2 and 3, 1 is a ceramic green sheet, 2 is an internal electrode pattern, 3 is a step-eliminating ceramic pattern, 4
Is a composite sheet, 30 is a step-resolving ceramic pattern 3
No. 10 is a carrier film.

A ceramic slurry is applied to the surface of the carrier film 10 by a die coating method and is formed into a uniform thickness with a blade. The flat ceramic slurry is dried to form the ceramic green sheet 1 ((a) of FIG. 2 and (a) of FIG. 3).

Next, as shown in FIG. 1, the carrier film 10 on which the ceramic green sheet is formed passes through a plurality of tension rolls 52 and then a gravure roll 53.
reach a. The gravure roll 53a is provided with a gravure printing plate having a concave portion filled with the ceramic paste 31 in a predetermined shape. A part of the gravure roll 53a is immersed in the ceramic paste 31 stored in the ceramic paste tank 55a, and the ceramic paste 31 is supplied to the concave portion of the gravure printing plate while rotating.
The surplus portion of the supplied ceramic paste 31 is scraped off by the doctor blade 56a, and only the necessary amount is filled in the concave portion. The impression cylinder 54a rotates in synchronization with the gravure roll 53a. As the carrier film 10 passes between the gravure roll 53a and the impression cylinder 54a, the ceramic paste 31 is transferred to the surface of the ceramic green sheet 1 in a predetermined shape. The transferred ceramic paste 31 is dried by passing through the drying furnace 57a to form the level difference eliminating ceramic pattern 3 ((b) of FIG. 2 and (b) of FIG. 3).

Here, the ceramic paste 31 spreads in the outward direction of the pattern to form the bleed 30 after being transferred and before being dried.

The carrier film 10 provided with the ceramic green sheet 1 on which the step-resolving ceramic pattern 3 is formed reaches the gravure roll 53b after passing through the plurality of tension rolls 2. On the gravure roll 53b, a gravure printing plate having a predetermined shape and having a recess filled with the conductive paste 21 is installed. Gravure roll 53
Part b is immersed in the conductive paste 21 stored in the conductive paste tank 55b, and supplies the conductive paste 21 to the concave portion of the gravure printing plate while rotating. Excessive amount of the supplied conductive paste 21 is scraped off by the doctor blade 56b, and only the necessary amount is filled in the concave portion.
The impression cylinder 54b rotates in synchronization with the gravure roll 53b. When the carrier film 10 passes between the gravure roll 53b and the impression cylinder 54b, the conductive paste 21 is transferred onto the surface of the ceramic green sheet 1 into the frame formed of the step-removing ceramic pattern 3. Here, since there is a wall formed by the step-resolving ceramic pattern 3, it is possible to prevent the transferred conductive paste 21 from spreading. The conductive paste 21 thus transferred is dried by passing through the drying furnace 57b to form the internal electrode pattern 2 ((c) of FIG. 2 and (c) of FIG. 3).

The gravure printing method is a method in which the transfer amount is determined by the recesses provided in the gravure printing plate as described above. Therefore, the transferable thickness is limited depending on the depth of the recess and the physical characteristics (viscosity, etc.) of the transfer material used. For example, if the thickness is set to 0.3 μm or less,
Scratches and the like are likely to occur. On the contrary, even if the thickness is 1.5 μm or more, the thickness of the gravure printing plate is limited, and it is not possible to supply such a transferred material (ink) at one time. For this reason, the thickness of the step-resolving ceramic pattern 3 and the internal electrode pattern 2 is preferably 0.3 μm to 1.5 μm.

The two-layer composite sheet 4 thus formed is peeled off from the carrier film 10 and a plurality of layers are laminated.
A laminated body is formed by pressure bonding. In the laminated body, ceramic layers made of ceramic green sheets 1 and layers made of internal electrodes and level difference eliminating ceramics are alternately laminated. Next, the laminated body is cut in the thickness direction and fired to form individual elements, and a conductive paste is applied to the elements and sintered to form external electrodes, thereby forming a laminated ceramic capacitor. To do.

With this structure, the conductive paste 21 can be prevented from bleeding and the internal electrode pattern 2 having a predetermined area can be easily formed. Therefore, a laminated electronic component having highly accurate characteristics can be manufactured.

Next, a method of manufacturing the laminated electronic component according to the second embodiment will be described with reference to FIGS.
FIG. 4 is a sectional view showing a stacking process, and FIG. 5 is a partial external perspective view thereof. In FIGS. 4 and 5, 1 is a ceramic green sheet, 2 is an internal electrode pattern, 3 is a pattern for level difference eliminating ceramics, 4 is a composite sheet, 30 is a blur of the pattern for level difference eliminating ceramics, and 10 is a carrier film.

In the method of manufacturing a laminated ceramic capacitor, which is a laminated electronic component according to the second embodiment, the gravure printing process shown in FIG. 1 is used, and the carrier film 10 on which the ceramic green sheet is not previously formed is used.

The carrier film 10 reaches the gravure roll 53a after passing through the plurality of tension rolls 2. As described above, the gravure roll 53a transfers the ceramic paste 31 directly to the surface of the carrier film 10 to form the level difference eliminating ceramic pattern 3 ((a) of FIG. 4 and (a) of FIG. 5). Here, the ceramic paste 31 spreads in the outward direction of the pattern to form the bleed 30 after being transferred and before being dried. Next, the conductive paste 21 is transferred by the gravure printing roll 53b to the inside of the frame formed by the step difference eliminating ceramic pattern 3 on the surface of the carrier film 10 to form the internal electrode pattern 2 ((b) of FIG. 4 and FIG. 5). (B)). In this way, the ceramic slurry is applied and dried on the surface of the layer formed of the step eliminating ceramic pattern 3 and the internal electrode pattern 2 by the die coating method to form the ceramic green sheet 1 ((in FIG. 4). c), (c) of FIG.

The two-layered sheet thus formed is peeled from the carrier film 10 and a plurality of layers are laminated and pressure-bonded to form a laminate. In the laminated body, ceramic layers made of ceramic green sheets 1 and layers made of internal electrodes and level difference eliminating ceramics are alternately laminated. Next, the laminate is cut in the thickness direction and fired to form individual elements, and a conductive paste is applied to the elements and sintered to form external electrodes.
Configure a monolithic ceramic capacitor.

With such a structure, the conductive paste 21 can be prevented from bleeding and the internal electrode pattern 2 having a predetermined area can be easily formed. Therefore, a laminated electronic component having highly accurate characteristics can be manufactured.

Further, the angle formed by the ridge of the internal electrode pattern in contact with the carrier film is an obtuse angle, and the shape is such that it is wrapped with the pattern for eliminating step difference. For this reason, when peeling the two-layer composite sheet from the carrier film, the wrapping part of the step-resolving ceramic pattern serves as a trigger for peeling, and peeling is performed so as to hold the internal electrode pattern with the step-resolving ceramic pattern. It is possible to suppress the peeling residue of the internal electrode pattern.

Further, by transferring the conductive paste directly to the surface of the carrier film and drying it to form the ceramic green sheet, damage to the ceramic green sheet by the solvent contained in the conductive paste can be suppressed.

By forming the ceramic green sheet by the die coating method, it is possible to form a flat surface over a wide range.

Furthermore, by forming the step difference eliminating ceramic pattern and the internal electrode pattern by the gravure printing method, it is possible to process the pattern at a higher speed than screen printing. As a result, the processing capacity of the printing process, in which the load increases as the capacity increases, can be improved, and the cost can be reduced.

In the above-mentioned embodiment, the description was given using the laminated ceramic capacitor, but the present invention is not limited to this, and the present invention is also applicable to laminated electronic components having internal electrodes, such as laminated inductors and laminated LC filters. Can be applied. Further, in the above embodiment, the two-layer composite sheet is formed, but the present invention is not limited to this, and a two-layer or more composite sheet may be formed.

[0039]

According to the present invention, a ceramic paste is gravure-printed on the surface of a carrier film to form a step-resolving ceramic pattern, and then a conductive paste is gravure-printed on a portion where the step-resolving ceramic pattern is not formed. To form an internal electrode pattern, apply a ceramic slurry to the surface of the layer formed by the step-eliminating ceramic pattern and the internal electrode pattern to form a ceramic green sheet, form a composite sheet, and form the composite sheet. By stacking, the internal electrode area can be formed with high precision, and a laminated electronic component having high precision characteristics can be manufactured.

Further, since the step eliminating ceramic pattern is formed so as to wrap around the internal electrode pattern, it can be easily peeled when peeled from the carrier film, and a highly reliable laminated electronic component is easily manufactured. can do.

Further, according to the present invention, the ceramic slurry is applied to the surface of the carrier film to form a ceramic green sheet, and the ceramic paste is gravure-printed on the surface of the ceramic green sheet.
After forming the step-eliminating ceramic pattern, the internal electrode pattern is formed by gravure-printing a conductive paste on the non-formation-deviating ceramic pattern-forming portion.
By forming the composite sheet and stacking the composite sheets, the internal electrode area can be formed with high accuracy, and a laminated electronic component having high-precision characteristics can be manufactured.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of a gravure printing process for forming a ceramic pattern and an internal electrode pattern of a laminated electronic component according to a first embodiment.

FIG. 2 is a cross-sectional view showing a laminating process of a two-layer composite sheet in the laminated electronic component according to the first embodiment.

FIG. 3 is a partial external perspective view of a two-layer composite sheet forming the laminated electronic component according to the first embodiment.

FIG. 4 is a cross-sectional view showing a stacking process of a two-layer composite sheet in the multilayer electronic component according to the second embodiment.

FIG. 5 is a partial external perspective view of a two-layer composite sheet forming a laminated electronic component according to a second embodiment.

FIG. 6 is an enlarged partial cross-sectional view of a laminated body of a conventional monolithic ceramic capacitor.

FIG. 7 is a side sectional view showing an internal electrode pattern provided on a carrier film, a step-eliminating ceramic pattern, and a ceramic green sheet.

FIG. 8 is a diagram showing a state in which a two-layer composite sheet is peeled from a conventional carrier film.

[Explanation of symbols]

1-ceramic green sheet 2-Internal electrode pattern 20-Bleeding of internal electrode pattern 21-Remaining peeling of internal electrode pattern 2 22-Chip of internal electrode pattern 2 3-Step resolution ceramic pattern 30-Step Dissolution Ceramic Pattern Bleed 10-carrier film 21-conductive paste 31-ceramic paste 4-composite sheet 52-tension roll 53a, 53b-gravure roll 54a, 54b-impression cylinder 55a-ceramic paste tank 55b-conductive paste tank 56a, 56b-Doctor blade 57a, 57b-drying oven

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Ken Hashimoto             2-10-10 Tenjin, Nagaokakyo, Kyoto Stock             Murata Manufacturing Co., Ltd. (72) Inventor Shinichi Kogawa             2-10-10 Tenjin, Nagaokakyo, Kyoto Stock             Murata Manufacturing Co., Ltd. F-term (reference) 5E082 AA01 AB03 BB01 BC14 EE04                       EE23 FF05 FG04 FG06 FG26                       FG46 MM22

Claims (2)

[Claims] 1. An internal electrode is formed by gravure-printing a ceramic paste on a surface of a carrier film to form a pattern for eliminating step difference ceramics, and then gravure-printing a conductive paste on a non-formation portion of the pattern for eliminating step difference ceramics. A pattern is formed, and a ceramic slurry is applied to the surface of the layer including the step-resolving ceramic pattern and the internal electrode pattern to form a ceramic green sheet, and the step-resolving ceramic pattern and the internal electrode pattern are formed. A method of manufacturing a laminated electronic component, comprising: a step of forming a composite sheet including a layer and the ceramic green sheet; and a step of laminating the composite sheet. 2. A ceramic slurry is applied to the surface of a carrier film to form a ceramic green sheet, and a ceramic paste is gravure-printed on the surface of the ceramic green sheet to form a pattern for eliminating a step, and then a ceramic pattern is formed. A composite sheet including the ceramic green sheet, the step-resolving ceramic pattern, and a layer including the internal electrode pattern, by forming an internal electrode pattern by gravure-printing a conductive paste on a portion where the step-resolving ceramic pattern is not formed. And a step of laminating the composite sheet, the method for producing a laminated electronic component.