JP2003017362A - Manufacturing method of ceramic laminate - Google Patents

Abstract

(57) [Summary] [PROBLEMS] Even when the number of laminations is increased by making ceramic green sheets thinner, steps due to the thickness of the conductor pattern can be eliminated, deformation of the ceramic laminate can be suppressed, and insulation resistance can be reduced. Provided is a method for producing a ceramic laminate that can suppress the occurrence of a decrease or short-circuit failure. A step of printing a conductor paste on a main surface of a ceramic green sheet and simultaneously forming a shape holding pattern by separating from a conductor pattern; and forming the conductor pattern and the shape holding pattern. A plurality of ceramic green sheets 1 are laminated to form a base laminate 9.
And a step of forming a ceramic laminate molded body from which the shape maintaining pattern 5 has been removed by cutting in a direction perpendicular to the main surface of the base laminate 9.

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 ceramic laminated body, and more particularly to a method for manufacturing a ceramic laminated body in which a ceramic green sheet and a conductor pattern are thinly laminated such as a wiring board and a laminated ceramic capacitor. is there.

[0002]

2. Description of the Related Art In recent years, as electronic devices have become smaller and higher in density, wiring boards and laminated ceramic capacitors having a conductor pattern formed in a ceramic laminate have been required to be small and thin and have high dimensional accuracy.

For example, in a monolithic ceramic capacitor formed by thinning or multilayering a ceramic green sheet or a conductor pattern, a step due to the thickness of the conductor pattern is formed between a portion where the conductor pattern is formed and a portion where the conductor pattern is not formed. Are accumulated, the adhesion between the surrounding ceramic green sheets having no conductor pattern is weak, and delamination and cracks are likely to occur. Therefore, a device for eliminating the step on the ceramic green sheet has been attempted.

As a method for manufacturing such a ceramic laminate, for example, one disclosed in Japanese Patent Laid-Open No. 2000-311831 is known. In the method for manufacturing a ceramic laminated body disclosed in this publication, as shown in FIG. 4, first, a conductor paste is printed on the main surface of a ceramic green sheet 81 to form a plurality of rectangular conductor patterns 83 at predetermined intervals. After forming, a ceramic paste is printed between these conductor patterns 83 to form a ceramic pattern 85.
And the ceramic pattern 85 is applied so as to overlap the inclined surface 87 of the conductor pattern 83. As a result, the conductor pattern 8
It is described that the step due to the thickness of 3 can be substantially eliminated, and the ceramic green sheet 81 can be laminated without being affected by the thickness of the conductor pattern 83.

[0005]

However, in the method for manufacturing a ceramic laminate disclosed in the above-mentioned Japanese Patent Laid-Open No. 2000-311831, printing for the ceramic pattern 85 is based on the conductor pattern 83 formed in advance. A ceramic pattern 85 is formed by a two-step process of aligning the screen and printing a ceramic paste on this printing screen, and this ceramic pattern 85 is applied so as to overlap the inclined surface 87 of the conductor pattern 83. Therefore, there is a problem that the ceramic pattern 85 easily rides on the end portion 89 of the conductor pattern 83 due to a slight displacement of the printing screen.

Further, this manufacturing method has a problem that the manufacturing cost is increased because it requires two steps.

Further, in order to reduce the cost of electronic components in recent years, in order to manufacture a large number of ceramic laminates from the mother laminate, the ceramic green sheet 81 and the printing screen have a large work size. Is being done.

When the ceramic paste is printed using such a printing screen having a large effective size, in the peripheral area of the printing screen, the elongation rate due to the printing pressure is larger than that in the central portion, so that the conductor pattern 83 is formed. Due to the displacement of the ceramic pattern 85 with respect to the conductor pattern 83, the riding of the ceramic pattern 85 on the conductor pattern 83 is further increased, and a local increase in thickness occurs. There is a problem that delamination and cracks are likely to occur in the laminated body.

Therefore, the present invention provides a method for manufacturing a ceramic laminated body capable of suppressing the deformation, delamination and cracking of the ceramic laminated body in a small number of steps even when the number of laminated layers is increased by thinning the ceramic green sheets. The purpose is to provide.

[0010]

A method for manufacturing a ceramic laminate according to the present invention comprises a step of forming a ceramic green sheet and a conductor paste printed on the main surface of the ceramic green sheet to form a rectangular conductor pattern. Forming a plurality of patterns at a predetermined interval and forming a shape-retaining pattern between the conductor patterns so as to be separated from the conductor patterns, and a plurality of layers of ceramic green sheets on which the conductor patterns and the shape-retaining patterns are formed. A step of forming a matrix laminate by laminating, and a step of cutting and removing a portion of the matrix laminate on which the shape-retaining pattern is formed in the laminating direction of the matrix laminate to form a ceramic laminate compact. And a step of firing the ceramic laminated body formed body.

According to this structure, since the shape holding pattern is formed between the conductor patterns at the same time when the conductor patterns are formed, the step due to the conductor patterns can be almost eliminated, and the ceramic laminated body can be formed. Deformation can be suppressed and delamination and cracks can be prevented.

Further, after a plurality of ceramic green sheets on which the conductor patterns and the shape-retaining patterns are formed are laminated to form a mother laminate, pressure is applied to the mother laminate to improve the adhesion of the ceramic green sheets. At this time, the ceramic green sheets above and below the conductor pattern enter between the conductor pattern and the shape-retaining pattern to form an insulating layer, so that a margin portion can be easily formed around the ceramic laminate. .

Further, since the shape-retaining pattern is formed simultaneously with the conductor pattern by using the same plate-making, the printing process of the conductor pattern and the shape-retaining pattern can be performed in one step, and the printing pressure at the time of printing can be achieved. As a result, even if the plate is stretched in the peripheral region and misaligned during printing, the conductor pattern and the shape-retaining pattern can be formed with high accuracy while maintaining the shape and space.

Therefore, as in the conventional method for manufacturing a ceramic laminated body, the positional deviation between the conductor pattern and the ceramic pattern (shape retaining pattern) that occurs when the conductor pattern and the ceramic pattern (shape retaining pattern) are formed in two steps. It is possible to suppress the riding of the ceramic pattern (shape-retaining pattern) on the conductor pattern due to, and to suppress the accumulation of the thickness of the conductor pattern and the ceramic pattern (shape-retaining pattern) in the base laminate.

Further, since the accumulation of thickness is suppressed in the base laminate, it is possible to suppress the deformation of the base laminate at the time of pressurization and the local reduction of the thickness of the ceramic green sheet, thereby lowering the insulation resistance and short-circuit failure. Can be prevented.

Further, in this manufacturing method, since the shape-retaining pattern is cut and removed in the direction perpendicular to the main surface of the base laminate, the shape-retaining pattern containing the metal powder can be easily formed from the margin portion around the conductor pattern. It can be removed, a margin portion with high insulation can be formed, and the reliability of the ceramic laminate can be improved.

In the method for manufacturing the above ceramic laminate, it is desirable that the distance L ₂ between the conductor pattern and the shape-retaining pattern is 50 μm or more. Thus, if the distance L ₂ between the conductor pattern and the shape-retaining pattern is 50 μm or more,
Even if the ceramic green sheets are misaligned or cut, the electrical insulation between the conductor pattern and the shape retention pattern can be maintained, and the ceramic green sheet material can be reliably filled between the conductor pattern and the shape retention pattern. .

Further, in the above-mentioned method for producing a ceramic laminate, since the conductor pattern and the shape-retaining pattern have substantially the same thickness, it is possible to suppress the deviation of the ceramic green sheets from each other and to easily achieve a high degree of lamination. It is possible to flatten the laminated body.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION The method for producing a ceramic laminated body of the present invention is applied to, for example, a laminated ceramic capacitor which is one of electronic components.

As shown in FIG. 1 (a), the ceramic green sheet 1 constituting the laminated ceramic capacitor is
First, the carrier film 2 is formed by applying a ceramic slurry.

Next, as shown in FIG. 1B, a conductor paste is printed on one main surface of the ceramic green sheet 1 to form a plurality of conductor patterns 3 at predetermined intervals, and the conductors 3 are formed. Between the patterns 3, the shape retaining pattern 5 is formed simultaneously with the conductor pattern 3 by a conductor paste while being separated from the conductor patterns 3. In this case, first, the direction of cutting along the side margin 10 of the ceramic laminate will be described.

The shape retaining pattern 5 is formed between the conductor patterns 3 so as to have substantially the same thickness as the conductor patterns 3 so as to substantially eliminate a step due to the thickness of the conductor patterns 3.

Next, as shown in FIG. 1 (c), the ceramic green sheet 1 on which the conductor pattern 3 and the shape-retaining pattern 5 are formed is peeled from the carrier film 2 and a plurality of layers are laminated to form a base laminate 9. . Then, the base laminate 9 is pressed.

Next, as shown in FIG. 1D, when viewed from the side margin 10 side, the mother laminate 9 is perpendicular to the main surface in the laminating direction, that is, the upper surface of FIG. 1D. Then, the portion where the shape retention pattern 5 is formed is cut and removed by dicing 11 to produce a ceramic laminate molded body from which the shape retention pattern 5 made of a metal component is removed.

The cutting from the end margin 12 side is
As shown in FIG. 1 (d ′), the shape retention pattern 5 is removed and the conductor pattern 3 is cut so as to divide the central portion thereof.

Next, the ceramic laminate molded body obtained by cutting is fired under a predetermined atmosphere under temperature conditions to form a plurality of ceramic laminates.

Next, the formation of the conductor pattern 3 and the shape retention pattern 5 on the ceramic green sheet 1 will be described in detail.

That is, as shown in FIG. 2, on the one main surface side of the ceramic green sheet 1, a plurality of rectangular conductor patterns 3 formed by printing a conductor paste are formed at predetermined intervals L ₁ . these conductor patterns 3 between L _1, so as to substantially eliminate the difference in level due to the thickness of the conductive pattern 3, the conductive pattern 3 and the simultaneous printing shape retention pattern 5 are formed at intervals L _2.

The distance L ₂ between the end of the conductor pattern 3 and the end of the shape retention pattern 5 is 50 μm or more. As a result, even if the conductor pattern 3 and the shape retention pattern 5 are misaligned due to printing, misalignment at the time of cutting, and misalignment at the time of cutting, the electrically insulated margins 10 and 12 can be secured around the ceramic laminate.

In particular, when the base laminate 9 is pressed, the base laminate 9 is prevented from being deformed due to the burial of the ceramic green sheet 1 between the conductor pattern 3 and the shape-retaining pattern 5 to prevent delamination and cracks. For the reason of suppressing, L ₂ is set to 50 to 300 μm, and further L ₂ is 70 to 200 μm, particularly 80 to suppress deformation of the ceramic laminate molded body and prevent short circuit failure.
˜150 μm.

In particular, the shape retaining pattern 5 formed on the end surface (end margin 12) of the ceramic laminated body on which the external electrodes are formed is more closely connected to the conductor pattern 3 than the shape retaining pattern 5 formed on the side margin 10. Insulation is ensured by widening the distance L ₂ .

Further, since there is a slight gap between the conductor pattern 3 and the shape-retaining pattern 5 as described above, a metal for eliminating the step due to the thickness of the conductor pattern 3 between the conductor patterns 3. Even if the shape-retaining pattern 5 made of components is formed, when the ceramic green sheets 1 having the conductor pattern 3 and the shape-retaining pattern 5 are multilayered to form a ceramic laminate, the ceramic green sheets 1 are temporarily laminated. The air stored in can be effectively degassed when pressurized.

Further, as shown in FIG. 3, the outer peripheral ends of the conductor pattern 3 and the shape retaining pattern 5 formed on the surface of the ceramic green sheet 1 each have an inclined surface 7. As a result, the drop of the ceramic green sheet 1 buried between the conductor pattern 3 and the shape retention pattern 5 can be reduced.

The angle θ ₂ of the inclined surface at the end of the shape retention pattern 5 with respect to the ceramic green sheet 1 is 0.
The range is 5 ° to 40 °. In particular, when the laminated pressure is applied, the angle θ ₂ is 1 ° to 20 °, and further ₂ because the ceramic green sheet 1 is prevented from being embedded between both patterns and the deformation of the ceramic laminate is suppressed.
° to 10 ° is more desirable. In order to make such an inclined surface, it is necessary to make the viscosity characteristic in the conductor paste thixotropic.

The angle θ ₁ between the inclined surface 7 at the end of the conductor pattern 3 and the inclined surface 7 at the end of the shape retaining pattern 5 is 12
The range is 0 ° to 179 °. As a result, burial suppression, concave deformation, and adhesion can be improved. In particular, the angle θ ₁ is 135 ° to 178 for the reason that the ceramic green sheet 1 is prevented from being buried between both patterns and the concave deformation of the ceramic laminated body is suppressed when laminated and pressed.
°, and for the reason of improving the adhesion, 150 ° ~
170 ° is more desirable.

The angles θ ₁ and θ ₂ are measured by simply using the stylus type surface roughness meter for the conductor pattern 3 and the shape retaining pattern 5 formed on the ceramic green sheet 1. In addition, in detail, the cross-section can be observed and measured using a scanning electron microscope.

In the method for producing a ceramic laminate of the present invention, first, a ceramic slurry is applied on the carrier film 2 and the ceramic green sheet 1 is formed by the slip casting method. The carrier film 2 used here is used.
As the carrier film 2, a PET film is used as the carrier film 2. The surface of the carrier film 2 is coated with a silicone resin for release to improve the releasability of the thin ceramic green sheet 1.

As the ceramic slurry, for example, a mixture of ceramic powder, a binder made of polyvinyl butyral resin, and a solvent in which the binder is dissolved and toluene and ethyl alcohol are preferably used. As the other binder, an acrylic resin may be used in terms of dispersibility with ceramic powder or solvent, strength of the ceramic green sheet 1, and binder removal property.

Specific examples of the ceramic material include B
aTiO₃-MnO-MgO-Y₂O ₃Ceramic powder such as
It can be used because the powder has reduction resistance.
Further, glass powder may be added.

Then, this ceramic green sheet 1
The particle size of the ceramic powder used for is set to 1.5 μm or less for the reason that the ceramic green sheet 1 is made thin, and 0.1 to 0.9 for the reason of high dielectric property and high insulating property.
μm is desirable.

Ba which is the main raw material of the ceramic powder
TiO₃Powder synthesis methods include solid phase method and liquid phase method (via oxalate).
There is a hydrothermal synthesis method, but
Hydrothermal synthesis method is desired due to its narrow cloth and high crystallinity.
Good And BaTiO ₃The average specific surface area of the powder is
1.1-10m²/ G is preferred.

Specific examples of the slip casting method include a pulling method, a doctor blade method, a reverse roll coater method, a gravure coater method, a screen printing method, a gravure printing method and a die coater method.

Then, in such a method for producing a ceramic laminate, the ceramic slurry coated on the release-treated carrier film 2 is heated from room temperature to a temperature equal to or higher than the evaporation temperature of the solvent in any step. Then dried. The heating temperature is stepwise, for example, room temperature, 60 ° C., and 100 ° C., which is higher than the solvent evaporation temperature. By heating stepwise in this manner, the solvent is dried uniformly and gradually from the liquid slurry film,
Roughness of the surface due to boiling marks of the solvent due to rapid drying at a high temperature and the peeled surface can be eliminated.

In the final zone of the drying section, since the drying temperature is set to the evaporation temperature of the solvent or higher, there is no binder settling or binder agglomeration due to long-time drying at low temperature, and there is no pinhole or film breakage. It is possible to form a uniform ceramic green sheet 1 having no such defects.

The thickness of the ceramic green sheet 1 is preferably 1 to 4 μm for the reason of miniaturization and large capacity.

Next, on the produced ceramic green sheet 1, a conductor paste is printed by a method such as screen printing or gravure printing to simultaneously form the conductor pattern 3 and the shape retention pattern 5.

This conductor paste contains metal particles, an organic solvent containing a mixture of an aliphatic hydrocarbon and a higher alcohol, an organic binder containing ethyl cellulose soluble in the organic solvent, and an organic solvent resistant to the organic solvent. And an organic binder made of a soluble epoxy resin.

Further, the viscosity of the conductor paste can be controlled by optimizing the metal powder, the binder, the solvent and the dispersant in the conductor paste, whereby the thixotropic property can be imparted to the conductor paste. . By controlling the viscosity characteristic of the conductor paste in this way, the inclined surface 7 is formed at the end of the conductor pattern 3 and the angle thereof can be controlled.

As the metal particles contained in the conductive paste, base metal particles having an average particle diameter of 0.05 to 0.5 μm are used. As base metals, there are Ni, Co, Cu,
Ni is desirable because the firing temperature of the metal matches the firing temperature of general insulators and the cost is low.
It is also possible to use an alloy composed of these metals, which is advantageous in oxidation resistance.

The average particle size of the base metal particles is 0., in order to improve the dispersibility of the metal powder and prevent the metal from becoming large during firing.
The range of 1 to 0.6 μm is desirable. The average particle size of the base metal is preferably 0.15 to 0.4 μm because a dense and smooth metal film is formed.

In addition, the conductor paste has a solid content of
In addition to the metal powder, it is preferable to mix and use fine ceramic powder in order to suppress the sinterability of the conductor pattern. In order to form a uniform particle diameter of the conductor pattern 3 and improve the smoothness, the ceramic powder is preferable. Has a particle size of 0.15
0.3 μm is desirable.

The thickness of the conductor pattern 3 formed by using such a conductor paste is smaller than that of the capacitor.
From the viewpoint of high reliability, the thickness is preferably 2 μm or less, and particularly preferably 1 μm or less.

Also, such a conductor pattern 3 and shape
In order to form the shape retention pattern 5,
Viscosity is thixotropic and shear rate
0.01s^-1The viscosity of the conductor paste at₁, Let
Breaking speed is 100s^-1Viscosity of the conductor paste in
Η₂, Then η₂/ Η₁> 5
In particular, the shape retention is improved without blurring to the conductor pattern.
Can be provided, and the conductor patterns 3 are spaced at predetermined intervals.
Is it because the shape retention pattern 5 can be formed with high accuracy?
As the viscosity characteristics of the conductor paste,
In the range, η ₂/ Η₁Is in the range of 10 to 50
However, the reason that the deformation of the shape retention pattern 5 can be suppressed
More desirable from.

Further, the viscosity of the conductor paste can be controlled by optimizing the metal powder, the binder, the solvent and the dispersant in the conductor paste, whereby the thixotropic property can be imparted to the conductor paste. . By controlling the viscosity characteristic of the conductor paste in this way, the inclined surface 7 is formed at the end of the conductor pattern 3 and the angle thereof can be controlled.

The viscosity of the conductor paste can be measured by using RS-150 manufactured by Haake Co., Ltd. and a cone type viscometer having a cone angle of 1 ° and a diameter of 50 mm.

It is desirable that the difference in SP value between the binder contained in the conductor paste and the binder contained in the ceramic green sheet 1 is 2 or less. In particular, the ceramic green sheet 1 and the conductor pattern 3 are preferable. And S for improving the adhesion with the shape retention pattern 5.
The difference in P value is more preferably in the range of 0 to 1.5.

The dicing 11 for cutting the base laminate 9 of the present invention perpendicularly to its main surface has a width of 0.1 to 0.3 mm, which is larger than the width of the shape-retaining pattern 5. Is desired to be completely removed and the cutting precision thereof is improved.

As described above, according to the present invention, a plurality of conductor patterns 3 are formed on the ceramic green sheet 1 with a conductor paste at predetermined intervals, and the shape retaining pattern 5 is provided between the conductor patterns 3. Since the conductor pattern 3 and the shape retaining pattern 5 can be easily formed with high precision by forming them by the simultaneous printing, the step of the conductor pattern 3 is almost eliminated, the deformation of the ceramic laminate can be suppressed, and the delamination can be suppressed. And cracks can be prevented.

Further, in this manufacturing method, the shape retaining pattern 5 is cut in the direction perpendicular to the main surface of the base laminate 9, so that the margin portions 10 and 12 around the conductor pattern 3 which originally do not require metal powder are used. By removing the shape-retaining pattern 5 made of metal powder, the margin portions 10 and 12 having high insulation can be easily formed, and the reliability of the ceramic laminate can be improved.

[0060]

Example A monolithic ceramic capacitor, which is one of the ceramic laminates, was manufactured as follows.

The ceramic green sheet is made of BaTiO 3.
_{3 to} 99.5 mol% and 0.5 mol% of MnO to 100 mol parts of the composition, 0.5 mol part of Y ₂ O ₃ and M
0.5 parts by mole of gO was added to make these ceramic components 1
Vehicle 55 consisting of 5.5% by weight of ethyl cellulose and 94.5% by weight of petroleum alcohol, relative to 00 parts by weight.
% By weight, and kneaded with a ball mill to prepare a ceramic slurry, which is formed on a belt-shaped carrier film made of polyester by using a die coater method and has an average thickness of 2 μm.
The ceramic green sheet of was produced.

The conductor paste is Ni having a particle diameter of 0.2 μm.
45% by weight of powder, 5.5% by weight of ethyl cellulose and 55% by weight of a vehicle composed of 94.5% by weight of petroleum alcohol were kneaded by a three-roll mill to prepare. The viscosity of the conductor paste at a shear rate of 0.01 s ^-1 is η ₁ , and the viscosity of the conductor paste at a shear rate of 100 s ^-1 is η _2.
Then, η ₂ / η ₁ was set to 12.

Next, the above-mentioned conductor paste is printed on the main surface of the obtained ceramic green sheet by using a screen printing device having a printing screen of 150 mm square, and the rectangular conductor pattern and the shape retention therebetween are held. The pattern was simultaneously formed and dried.

The conductor pattern and the shape-retaining pattern had a thickness of 1.5 μm, and had substantially the same thickness.

The angle θ ₁ of the inclined surface at the outer peripheral end of the shape retaining pattern and the angle θ ₂ between the inclined surface of the outer peripheral end of the conductor pattern and the inclined surface at the end of the shape retaining pattern are
The angle of the resist film on the printing screen and the viscosity of the conductor paste were adjusted to 8 ° and 160 °, respectively.

The space L ₂ between the conductor pattern and the shape-retaining pattern was formed by changing the design as shown in Table 1.

Next, this ceramic green sheet is
200 layers are stacked by alternately shifting the stacking positions in the end face direction of the opposing conductor patterns connected to the external electrodes, and further 10 ceramic green sheets on which conductor patterns and ceramic patterns are not formed are stacked above and below the stacked layers. Then, the first pressing was performed to form a temporary laminate.

In the temporary laminate produced under these conditions, the ceramic green sheets were not completely adhered to each other, and a slight space was formed in the portion surrounded by the conductor pattern, the ceramic pattern and the green sheet.

Next, this temporary laminated body is subjected to a second laminating press at a temperature of 100 ° C. and a pressure of 20 MPa to deaerate the air in the temporary laminated body, and at the same time, the ceramic green sheet coated with the conductor pattern and the upper and lower portions of the ceramic green sheet. A ceramic green sheet made of the same material as the ceramic green sheet was laminated and completely adhered to obtain a base laminate.

In the base laminate forming the ceramic laminate of the present invention, the shape retention pattern is formed together with the conductor pattern on one main surface of the ceramic green sheet on which the conductor pattern is formed. It was possible to form the base laminate without deformation of the ceramic green sheet or the conductor pattern due to heating and pressing.

Next, dicing was performed along the shape-retaining pattern of the base laminate to cut it into a lattice shape to obtain a ceramic laminate compact. At this time, by setting the width of the dicing to be the same as the width of the shape-retaining pattern, the metal component contained in the shape-retaining pattern was completely removed from the side surface of the ceramic laminate body.

Next, the ceramic laminated body formed in the central portion of the mother laminated body and the ceramic laminated body formed in the peripheral portion were separated. At this time, a radius of 40 mm from the center of the base laminate was defined as the central part, and the others were defined as the peripheral part. One end of the conductor pattern was alternately exposed on both end faces of this ceramic laminate molded body.

Next, this ceramic laminated body was subjected to 50 in an atmosphere of 250 ° C. or 0.1 Pa in an oxygen / nitrogen atmosphere.
The mixture was heated to 0 ° C. and subjected to a debayering treatment.

Further, with respect to the ceramic laminated body formed body after removing the by-pass, in an oxygen / nitrogen atmosphere of 10 ⁻⁷ Pa, 125
The ceramic laminate was fired at 0 ° C. for 2 hours and further subjected to reoxidation treatment at 900 ° C. for 4 hours in an oxygen nitrogen atmosphere of 10 ⁻² Pa to obtain a ceramic laminate. After firing, the Cu paste is baked on the end surface of the ceramic sintered body at 900 ° C., and Ni / S is further added.
An outer conductor connecting to the inner conductor was formed by performing n plating.

The external dimensions of the monolithic ceramic capacitor thus obtained are 0.8 mm in width and 1.6 mm in length.
Met. Further, there was no step due to the inner conductor, and this inner conductor was flat without being curved.

Next, with respect to the monolithic ceramic capacitor obtained after firing, 300 samples each formed in the central portion and the peripheral portion of the base laminate were observed with a 40 × binocular microscope, and the monolithic ceramic capacitor was obtained. The presence or absence of cracks on the end surface of the multilayer ceramic capacitor was evaluated, and the end surface and the side surface of the laminated ceramic capacitor were each polished to evaluate the presence or absence of delamination at the peripheral edge of the internal conductor.

Further, with respect to the same number of samples as the delamination evaluation, an insulation resistance tester was used to measure an applied voltage of 6.3 V and an application time of 1 minute, and a short circuit failure was evaluated with an insulation resistance of> 10 ⁵ Ω as a guide. .

On the other hand, as comparative examples, a ceramic laminate prepared by forming a conductor pattern and a shape-retaining pattern in two steps using a conductor paste, and a sample in which the shape-retaining pattern was not formed between the conductor patterns were prepared. It was produced and evaluated.

[0079]

[Table 1]

From the results shown in Table 1, the sample No. No. 1 in which the shape retention patterns were simultaneously formed so as to be spaced apart from each other between the conductor patterns inside the multilayer ceramic capacitor, and the distance was set to 30 to 300 μm. In Examples 1 to 8, short-circuit defects were observed in some of the samples, but there was little delamination after firing in both the samples in the central portion and the peripheral portion of the base laminate, and in particular, the spacing between the conductor pattern and the shape retention pattern was reduced. 50-200 μm
Sample No. In Nos. 2 to 7, almost no delamination was observed, and especially in the interval of 80 to 150 μm, there was no delamination and no short circuit failure.

On the other hand, the sample No. prepared by the two-step printing process for the conductor pattern and the shape-retaining pattern. In No. 9, the space between the conductor pattern and the shape retention pattern is designed to be 50 μm.
Even when set to, delamination and short circuit defects frequently occurred due to the contact of the shape retention pattern on the conductor pattern and the riding of the shape retention pattern. In addition, in Sample No. 1 in which the shape retention pattern was not formed between the conductor patterns. In No. 10, the delamination frequently occurred due to the accumulation of the steps of the conductor pattern, and the short circuit defect also increased.

[0082]

As described in detail above, according to the present invention,
A plurality of conductor patterns are formed on the ceramic green sheet at predetermined intervals using a conductor paste, and
By forming the shape retention pattern between the conductor patterns by simultaneous printing, the conductor pattern and the shape retention pattern can be formed with high accuracy, the steps of the conductor pattern are almost eliminated, and the deformation of the ceramic laminate can be suppressed. At the same time, delamination and short circuit defects can be prevented.

Further, in this manufacturing method, the shape-maintaining pattern is cut in the direction perpendicular to the main surface of the base laminate, so that the metal powder is formed from the margin portion around the conductor pattern where the metal powder is originally unnecessary. By removing the holding pattern, a highly insulating margin portion can be easily formed, and the reliability of the ceramic laminate can be improved.

[Brief description of drawings]

FIG. 1 shows a process drawing for producing a ceramic laminate of the present invention.

FIG. 2 is a schematic perspective view showing a shape-retaining pattern formed on the ceramic green sheet of the present invention with a space between the conductor patterns.

FIG. 3 is a schematic cross-sectional view showing a shape retaining pattern formed on the ceramic green sheet of the present invention with a space between the conductor patterns.

FIG. 4 is a schematic cross-sectional view showing a conventional ceramic pattern formed on a ceramic green sheet so as to overlap a conductor pattern.

[Explanation of symbols]

1 Ceramic green sheet 2 carrier film 3 conductor pattern 5 Shape retention pattern 7 slope 9 Base laminate

Continued front page    F-term (reference) 5E001 AC07 AH01 AH05 AH06 AH09                       AJ01 AJ02                 5E082 AB03 BC38 EE04 EE35 FG06                       FG26 LL01 LL02 LL03 PP09                 5E346 AA02 AA12 AA15 AA22 AA32                       AA51 BB11 BB15 BB16 BB20                       CC16 DD34 EE24 EE25 EE27                       EE28 EE30 GG08 GG09 HH11

Claims (3)

[Claims] 1. A step of forming a ceramic green sheet, printing a conductor paste on a main surface of the ceramic green sheet to form a plurality of rectangular conductor patterns at predetermined intervals, and between the conductor patterns. A step of forming a shape-retaining pattern separately from the conductor pattern; a step of laminating a plurality of ceramic green sheets on which the conductor pattern and the shape-retaining pattern are formed to form a matrix laminate; A step of cutting and removing the portion of the laminated body on which the shape retention pattern is formed in the laminating direction of the base laminated body to form a ceramic laminated body molded body; and a step of firing the ceramic laminated body molded body, A method for producing a ceramic laminate, comprising: 2. The distance L ₂ between the conductor pattern and the shape-retaining pattern is 50 μm or more.
The method for producing a ceramic laminate according to 1. 3. The method for producing a ceramic laminate according to claim 1, wherein the conductor pattern and the shape-retaining pattern have substantially the same thickness.