JP3506086B2 - Manufacturing method of multilayer ceramic electronic component - Google Patents

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 monolithic ceramic electronic component such as a monolithic capacitor, and more specifically, a method for manufacturing a monolithic ceramic electronic component formed by using a thin ceramic green sheet. Regarding

[0002]

2. Description of the Related Art In manufacturing a monolithic ceramic electronic component such as a monolithic capacitor, a plurality of ceramic green sheets printed with internal electrodes are laminated and pressed in the thickness direction to obtain a laminate. Then, by firing this laminated body, a ceramic sintered body on which internal electrodes are formed is obtained.

By the way, in a multilayer capacitor, for example, the thickness of the ceramic sintered body layer between the internal electrodes has been reduced in order to achieve miniaturization and large capacity. Therefore, it is necessary to use thinner ceramic green sheets during manufacturing.

However, when the thickness of the ceramic green sheet becomes thin, it becomes difficult to handle the ceramic green sheet alone. Therefore, conventionally, a method has been proposed in which a ceramic green sheet is formed on a carrier film made of a synthetic resin film and handled while being supported by the carrier film.

Further, Japanese Unexamined Patent Publication No. 63-102216 discloses a method of stacking ceramic green sheets using the suction jig 51 shown in FIG. here,
Ceramic green sheet 5 on carrier film 52
3 are stacked. Internal electrodes 54 are formed by screen-printing a conductive paste on the upper surface of the ceramic green sheet 53. On the other hand, the suction jig 51
It has a suction jig main body 55 and a cutter 56. The suction jig body 55 has a large number of suction holes 55b opened on the lower surface 55a.
Have. The suction hole 55b is connected to a suction source such as a vacuum pump (not shown). The cutter 56 has a rectangular frame shape, and has a lower edge as a cutting blade.

In stacking the ceramic green sheets 53, after the internal electrodes 54 are printed, the suction jig 51 is lowered and the ceramic green sheets 53 are punched out into a rectangular shape by a cutter 56, as shown in FIG. Thereafter, the ceramic green sheet 53 having the internal electrodes 54 printed thereon is sucked onto the lower surface 55a of the suction jig body 55 by suction through the suction holes 55b. Next, the suction jig 51 is moved upward, conveyed into a stacking jig (not shown), suction is stopped,
The adsorbed ceramic green sheet 53 is pressure-bonded to the previously laminated ceramic green sheet in the suction jig to be laminated. It is said that by repeating this process, the thin ceramic green sheets 53 can be sequentially laminated.

[0007]

However, in recent years,
Attempts have been made to reduce the thickness of the ceramic sintered body layer sandwiched between the internal electrodes. Therefore, as the ceramic green sheet 53, a very thin ceramic green sheet having a thickness of 5 μm or less has been used. When the thickness of the ceramic green sheet 53 is extremely thin as described above, the stacking method using the suction jig 51 may be difficult to handle and may damage the ceramic green sheet.

That is, a large number of suction holes 55b are formed in the suction jig body 55. The diameter of the suction hole 55b is about 0.1 to 1 mm. Therefore, when the thickness of the ceramic green sheet 53 is very thin, 10 μm or less, the size of the suction hole 55 b becomes relatively large with respect to the thickness of the ceramic green sheet 53, and the ceramic green sheet 53 is liable to be damaged by suction. Met.

If the diameter of the suction hole 55b is reduced, damage to the ceramic green sheet 53 can be reduced. However, the pressure loss increases and the suction holding force decreases. Further, the holding force by suction is generated only in the portion where the suction hole 55b is provided. Therefore, in order to reduce the diameter of the suction holes 55b and increase the suction holding force, a large number of suction holes 55b had to be formed. However, when a large number of suction holes 55b are formed, there is a problem in that the processing of the suction main body 55 takes a lot of work and the cost is very high.

When the suction jig 51 is used, 1
There is also a problem that the productivity is not sufficient because a stacking step of stacking and pressing each ceramic green sheet 53 on another ceramic green sheet must be performed.

The object of the present invention is to solve the above-mentioned drawbacks of the prior art, and even if a very thin ceramic green sheet is used, the ceramic green sheet is unlikely to be damaged and a plurality of ceramic green sheets are used. It is an object of the present invention to provide a method for manufacturing a monolithic ceramic electronic component including a process capable of easily and economically laminating.

[0012]

A method of manufacturing a laminated ceramic electronic component according to the present invention comprises a step of preparing a first composite sheet in which a first ceramic green sheet is formed on a first carrier film. A step of forming an internal electrode on the first ceramic green sheet, a step of preparing a second composite sheet having a second ceramic green sheet formed on a second carrier film, and a second step Laminating the composite sheet from the second ceramic green sheet side on the first ceramic green sheet having the internal electrodes formed thereon, and the second ceramic green sheet via the carrier film of the second composite sheet. A step of thermocompression bonding to the first ceramic green sheet side, a step of peeling the carrier film of the second composite sheet, and On the surface of the second ceramic green sheet exposed by peeling the carrier film, the position of the lower internal electrode is detected through the second ceramic green sheet, and the second ceramic green is referenced with the internal electrode as a reference. A step of forming internal electrodes on the sheet,
Repeating the step of laminating the second ceramic green sheet and the step of forming an internal electrode to obtain a laminated sheet supported by a carrier film by laminating a plurality of layers of the second ceramic green sheet via internal electrodes; Previous
By cutting the laminated sheet and sucking the laminated sheet,
The carrier from the carrier film, and
A step of laminating a plurality of the laminated sheets separated from the film to obtain a laminated body, a step of firing the laminated body to obtain a ceramic sintered body, and a plurality of external surfaces on the outer surface of the ceramic sintered body. And a step of forming an electrode.

In a particular aspect of the method for manufacturing a monolithic ceramic electronic component according to the present invention, the thermocompression bonding is performed using a calendar roll with a built-in heater. In a more specific aspect of the method for manufacturing a multilayer ceramic electronic component according to the present invention,
The thickness of the second ceramic green sheet is 5 μm
The following are used, and in a more specific aspect, 2 μ
A ceramic green sheet having a thickness of m or less is used.

In another specific aspect of the present invention, the second ceramic green sheet is laminated and the internal electrodes are formed so that the laminated sheet has a thickness of 3 μm or more.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be clarified by describing specific examples of the method for manufacturing a laminated ceramic electronic component according to the present invention with reference to the drawings.

In this embodiment, a monolithic capacitor is manufactured as a monolithic ceramic electronic component. First, as shown in FIG. 2A, the ceramic green sheet 2 is formed on the carrier film 1. As the carrier film 1,
Polypropylene, polyethylene terephthalate, PEN
An appropriate synthetic resin film such as the above can be used.
The ceramic green sheet 2 is formed by forming a ceramic slurry by an appropriate sheet forming method. Examples of this molding method include a doctor blade method, a reverse roll coater, and a method using a die coater. As described above, the ceramic green sheet 2 having a thickness of 1 to 5 μm is formed.

Next, as shown in FIG. 2B, an internal electrode 3 is formed by screen-printing a conductive paste such as Ag paste on the ceramic green sheet 2. The internal electrodes 3 may be formed by applying a conductive paste by a method other than screen printing. Instead of applying the conductive paste, a conductive agent may be applied by vapor deposition, sputtering or the like to form the internal electrodes 3. As described above, in this embodiment, the internal electrode 3 having a thickness after drying of 0.5 to 2 μm is formed.

Next, as shown in FIG. 1A, a ceramic green sheet 5 supported separately by a carrier film 4 is laminated on the ceramic green sheet 2 on which the internal electrodes 3 are printed. In this case, the thickness of the second ceramic green sheet 5 is 10 μm or less, preferably 1 to 5
It is about μm.

With the second ceramic green sheet 5 still supported by the carrier film 4, the ceramic green sheet 5 is placed on the ceramic green sheet 2 and the internal electrode 3 in the direction shown by the arrow in FIG. Stack.

Thereafter, as shown in FIG. 1 (b), pressure is applied from the upper surface of the carrier film 4 using a calendar roll 6 with a built-in heater. In this case, the calendar roll 6 is moved in the direction of the arrow while being in pressure contact with the back surface, that is, the top surface of the carrier film 4. In this way
The ceramic green sheet 5 is thermocompression bonded to the ceramic green sheet 2. The calender roll 6 is heated by a built-in heater, and the heating temperature is about 30 to 150 ° C.

After the thermocompression bonding, the carrier film 4 is peeled off to expose the ceramic green sheet 5. Then, as shown in FIG. 1 (c), using a screen 7,
The internal electrode 8 is formed on the second ceramic green sheet 5 in the same manner as the internal electrode 3.

By the way, when positioning the screen 7, the thickness of the ceramic green sheet 5 is 10 μm.
Since the thickness is very thin, such as m or less, the lower internal electrode 3 can be seen through. That is, according to the position of the internal electrode 3 printed through the ceramic green sheet 5,
The screen 7 can be positioned. Therefore, the internal electrode 8 is formed at a position that exactly overlaps the internal electrode 3. In addition, preferably, the thickness of the second ceramic green sheet 5 is set to 5 μm or less, and the position of the internal electrode 3 further below can be easily detected.

The position of the internal electrode 3 can be detected through the ceramic green sheet 5 by using an appropriate image processing apparatus. Using the above
As shown in FIG. 1D, the internal electrodes 8 are accurately formed on the second ceramic green sheet 5.

Next, similarly to the steps shown in FIGS. 1A and 1B, a third ceramic green sheet prepared separately is placed on the ceramic green sheet 5 and the internal electrodes 8. Laminate and thermocompress.

Thus, as shown in FIG. 3, the second ceramic green sheet 9 is laminated on the ceramic green sheet 5 and the internal electrodes 8. A structure in which the ceramic green sheets 2, 5 and 9 are laminated via the internal electrodes 3 and 8 is referred to as a laminated sheet 10.

Then, the suction jig 11 shown in FIG. 3 is prepared. The suction jig 11 includes a suction jig body 12 and a cutter 13. The suction jig body 12 has a large number of suction holes 12b opened on the lower surface 12a. The suction hole 12b is connected to a suction source (not shown), and is configured to be capable of sucking and holding the laminated sheet 10 on the lower surface 12a.

Further, the cutter 13 is the suction jig body 12
Is arranged so as to surround the periphery of the cutter 1.
The lower end of 3 is a cutting blade. The plane shape of the cutter 13 is a rectangular frame shape.

As shown in FIG. 4, the suction jig 11 is lowered, and the lower surface 12a of the suction jig body 12 presses the laminated sheet 10 into pressure contact. After that, the cutter 13 is lowered and the laminated sheet 10 is cut by the cutter 13. In this case, the cutting blade at the lower end of the cutter 13 is the carrier film 1
The carrier film 1 is lowered so as not to reach the lower surface of the carrier film 1. That is, the cutter 13 is lowered so as to cut only the laminated sheet 10 without cutting the carrier film 1.

In this state, the laminated sheet 10 is sucked through the suction holes 12b so that the laminated sheet 10 is placed on the lower surface 1 of the suction jig body 12.
Adsorbed on 2a. Therefore, by raising the suction jig 11 from the state shown in FIG. 4, the laminated sheet 10 can be peeled from the carrier film 1, and the laminated sheet 10 can be suction-held on the suction jig body 12 of the suction jig 11. Yes (see Figure 5).

Thereafter, the laminated sheet 10 is attached to the suction jig 11.
While holding, the suction jig 11 is moved as shown by the arrow in FIG. in this case,
The suction jig 11 is moved above the stacking jig 14 and lowered, and the suction holding by the suction jig is released while the stacking sheet 10 is pressure-bonded to the bottom surface 14a of the stacking jig 14 to release the stacking sheet 10. Can be moved into the stacking jig 14.

By repeating the process of obtaining the laminated sheet 10 described with reference to FIGS. 1 to 5 and laminating the laminated sheet 10 in the laminating jig 14, a large number of ceramic green sheets are formed through the internal electrodes. A laminated body that is laminated can be obtained.

By pressing the laminate thus obtained in the thickness direction, a mother laminate is obtained. According to a known laminated capacitor manufacturing technique, the mother laminated body is cut in the thickness direction so as to be a laminated body of each laminated capacitor unit and fired to obtain a ceramic sintered body 16 shown in FIG. Ceramic sintered body 16
Inside, a plurality of internal electrodes 17, 18 are alternately formed in the thickness direction. The plurality of internal electrodes 17 are drawn out to the first end surface 16 a of the ceramic sintered body 16. The plurality of internal electrodes 18 are drawn out to the second end surface 16b of the ceramic sintered body 16 opposite to the end surface 16a. Then, by forming the external electrodes 19 and 20 so as to cover the end faces 16a and 16b, the multilayer capacitor 21 is obtained.

In the manufacturing method of this embodiment, as described above,
A laminated sheet 10 in which the ceramic green sheets 2, 5 and 9 are laminated via the internal electrodes 3 and 8 is sequentially laminated using a suction jig 11. Therefore, even when the thickness of each of the ceramic green sheets 2, 5, 9 is very thin such as 10 μm or less, preferably 5 μm or less, the suction jig 11 of the same degree as that conventionally used is used, Lamination can be performed stably.

That is, in the past, when the thickness of the ceramic green sheet was 10 μm or less, it was difficult to handle one ceramic green sheet using the suction jig 51, whereas in this embodiment, it was 10 μm or less. The suction jig 11 handles the laminated sheet 10 formed by laminating the ceramic green sheets 2, 5, and 9 having the above thickness.

Therefore, the thickness of the laminated sheet 10 is 10 μm.
Since it exceeds m, the lamination work can be stably performed by using the suction jig 11 without damaging the lamination sheet 10. Further, since the laminated sheet 10 is thick, it is not necessary to increase the number of the suction holes 12b.

Further, in this embodiment, as described above, the thickness of the second ceramic green sheets 5 and 9 is 10 μm.
Due to the thinness below, the underlying internal electrodes can be seen through, which allows the internal electrodes to be accurately stacked.

Even when the thickness of the second ceramic green sheet is 10 μm or less, a plurality of ceramic green sheets can be easily and easily formed through the internal electrodes by using the suction jig 11 as described above. Can be economically laminated. Further, in the suction jig 11 of this type, if the thickness is 3 μm or more, the ceramic green sheets can be laminated without causing much damage. However, according to the manufacturing method of the present embodiment, the thickness of the laminated sheet 10 is Since it suffices that the thickness is 3 μm or more, for example, when three ceramic green sheets are laminated to form a laminated sheet, the thickness of each of the three ceramic green sheets is 1.0 μm or more. It can be laminated according to the method. Therefore, it is possible to easily obtain a multilayer capacitor in which the thickness of the ceramic sintered body layer between the internal electrodes is smaller than that in the conventional method.

In the above embodiment, when the second ceramic green sheet was thermocompression bonded to the first ceramic green sheet side, the calender roll with built-in heater was used. However, another thermocompression bonding device such as a heat press is used. May be.

Further, in the above-mentioned embodiment, the manufacturing method of the multilayer capacitor has been described, but it can be applied to the manufacture of other multilayer ceramic electronic components such as multilayer piezoelectric resonance components such as multilayer varistors and multilayer thermistors.

[0040]

According to the method of manufacturing a monolithic ceramic electronic component according to the present invention, after the internal electrodes are formed on the first ceramic green sheet, the ceramic green sheet having a thickness of 10 μm or less is formed on the second carrier film. The second composite sheet is laminated on the first ceramic green sheet from the second ceramic green sheet side, and the second ceramic green sheet is thermocompression-bonded to the first ceramic green sheet side. The laminated sheet is obtained by repeating the step of peeling the carrier film of the composite sheet and forming the internal electrode on the surface of the second ceramic green sheet, and stacking the second ceramic green sheet via the internal electrode. . Then, by cutting the laminated sheet and sucking it, the cut product
After peeling the layer sheet from the carrier film,
A laminated body is obtained by laminating the laminated sheets separated from the film, and a ceramic sintered body is obtained by firing the laminated body.

Therefore, even when the thickness of the first and second ceramic green sheets is reduced, it can be handled by using a suction jig or the like after obtaining the laminated sheet, and therefore the first and second ceramic green sheets can be handled. The thickness of the ceramic green sheet can be reduced, and a multilayer ceramic electronic component can be manufactured using a ceramic green sheet having a thickness of 10 μm or less, which is difficult to handle with a conventional suction jig. Therefore, a monolithic ceramic electronic component having a thin ceramic sintered body layer between the internal electrodes can be easily and economically obtained.

Further, since the above-mentioned laminated sheets are laminated, a conventionally used suction jig can be used. Therefore, a laminated ceramic electronic component having a thin ceramic sintered body layer between internal electrodes can be manufactured at low cost. Can be provided.

Since the thickness of the second ceramic green sheet is 10 μm or less, when the internal electrodes are formed on the second ceramic green sheet, the positions of the internal electrodes below the second ceramic green sheet are transparent. Can be confirmed. Therefore, the internal electrode can be accurately formed with reference to the actual position of the lower internal electrode.

When the thermocompression bonding is performed using a calendar roll with a built-in heater, the second ceramic green sheet can be easily thermocompression bonded to the first ceramic green sheet.

Further, in the present invention, even when the thickness of the second ceramic green sheet is 2 μm or less, a plurality of second ceramic green sheets are formed on the first ceramic green sheet.
When the thickness of the laminated sheet in which the ceramic green sheets are laminated exceeds 3 μm, using a conventional suction jig,
It is possible to provide a monolithic ceramic electronic component that can be easily handled and has a very thin ceramic sintered body layer between internal electrodes.

When the second ceramic green sheets are laminated and the internal electrodes are formed so that the thickness of the laminated sheet becomes 3 μm or more, the laminated sheet can be easily and easily formed by using a conventional suction jig or the like. It can be stably laminated.

[Brief description of drawings]

1A to 1D are cross-sectional views for explaining a process of laminating a second ceramic green sheet, thermocompression-bonding it, and further forming an internal electrode in one embodiment of the present invention. .

2A and 2B are views for explaining a step of preparing a first ceramic green sheet and a step of forming an internal electrode on the first ceramic green sheet in one embodiment of the present invention. FIG.

FIG. 3 is a cross-sectional view for explaining a step of holding a laminated sheet with a suction jig in one embodiment of the present invention.

FIG. 4 is a cross-sectional view for explaining a step of cutting a laminated sheet with a cutter when holding the laminated sheet with a suction jig in one embodiment of the present invention.

FIG. 5 is a cross-sectional view for explaining a process of holding, conveying, and stacking a laminated sheet using a suction jig in an example of the present invention.

FIG. 6 is a cross-sectional view showing a laminated capacitor as a laminated ceramic electronic component obtained according to an embodiment of the present invention.

FIG. 7 is a cross-sectional view for explaining an example of a conventional method for manufacturing a multilayer capacitor.

[Explanation of symbols]

1 ... Carrier film 2 ... the first ceramic green sheet 3 ... Internal electrode 4 ... Carrier film 5 ... Second ceramic green sheet 6 ... Calendar roll with built-in heater 7 ... Screen 8 ... Internal electrode 9 ... Second ceramic green sheet 10 ... Laminated sheet 11 ... Suction jig 12 ... Suction jig body 12a ... bottom surface 12b ... Suction hole 13 ... Cutter 14 ... Laminating jig 16 ... Ceramic sintered body 17, 18 ... Internal electrodes 19, 20 ... External electrodes 21 ... Multilayer capacitor

─────────────────────────────────────────────────── --- Continuation of the front page (56) Reference JP-A-2-155211 (JP, A) JP-A-9-129486 (JP, A) JP-A-8-130151 (JP, A) JP-A-63- 102216 (JP, A) JP-A-9-115765 (JP, A) JP-A-9-148134 (JP, A) JP-A-7-45461 (JP, A) JP-B-62-32603 (JP, B1) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01G 4/00-4/30 H01G 13/00

Claims (5)

(57) [Claims] 1. A step of preparing a first composite sheet in which a first ceramic green sheet is formed on a first carrier film, and a step of forming an internal electrode on the first ceramic green sheet. And a step of preparing a second composite sheet in which the second ceramic green sheet is formed on the second carrier film, and an internal electrode is formed from the second composite green sheet side of the second composite sheet. And a step of laminating it on the first ceramic green sheet, and a second step through the carrier film of the second composite sheet.
Thermocompression bonding the ceramic green sheet to the first ceramic green sheet side, peeling the carrier film of the second composite sheet, and the second ceramic green sheet surface exposed by peeling the carrier film. The step of detecting the position of the lower internal electrode through the second ceramic green sheet and forming the internal electrode on the second ceramic green sheet with the internal electrode as a reference; Repeating the steps of laminating the ceramic green sheets and forming the internal electrodes to obtain a laminated sheet supported by a carrier film by laminating a plurality of layers of the second ceramic green sheets through the internal electrodes; and By cutting and suctioning
A step of peeling the sheet from the carrier film , a step of stacking a plurality of the laminated sheets peeled from the carrier film to obtain a laminate, a step of firing the laminate to obtain a ceramic sintered body, And a step of forming a plurality of external electrodes on the outer surface of the ceramic sintered body. 2. The method for manufacturing a monolithic ceramic electronic component according to claim 1, wherein the thermocompression bonding is performed using a calendar roll with a built-in heater. 3. The method for producing a laminated ceramic electronic component according to claim 1, wherein the thickness of the second ceramic green sheet is 5 μm or less. 4. The method for producing a laminated ceramic electronic component according to claim 1, wherein the second ceramic green sheet has a thickness of 2 μm or less. 5. The method for manufacturing a laminated ceramic electronic component according to claim 4, wherein the second ceramic green sheets are laminated and the internal electrodes are formed so that the laminated sheet has a thickness of 3 μm or more.